TECHNICAL FIELD
[0001] The present invention relates to a training apparatus equipped with a training rod
driven by a motor, for supporting rehabilitation of upper and/or lower limbs of a patient
according to a predetermined training program.
5
BACKGROUND ART
[0002] Rehabilitation aimed at motor function recovery of upper and/or lower limbs of a
stroke patient with hemiplegia is usually performed by an occupational therapist or a physical
therapist, and hence there is a limitation in efficient offering of rehabilitation. For instance,
10 in rehabilitation aimed at motor function recovery of an upper limb, it is mainly required to
repeat as much as possible a correct movement of the paralyzed upper limb passively and
actively in a movement range slightly larger than current range. On the basis of the
rehabilitation for the motor function recovery, the occupational therapist or the physical
therapist teaches the correct movement to the patient and manually applies a load on the
15 upper limb of the patient so as to induce an active movement.
In this rehabilitation, the number of repetition is limited due to exhaustion of the
therapist. In addition, there may be a difference of medical quality of the rehabilitation
depending on experience of the therapist. Accordingly, in order to support the training by
the therapist, to eliminate the limitation due to exhaustion, and to standardize the medical
20 quality as much as possible, there is known a training apparatus as described in Patent
Citation 1, for example, which supports rehabilitation of a patient with a disabled limb such
as an arm. The apparatus is disclosed as an upper limb training apparatus including a fixed
3
frame that can be placed on a floor, a movable frame supported by the fixed frame so as to be
capable of tilting in all directions, and a training rod attached to the movable frame in an
expandable/contractible manner so as to be operated by a person who undergoes the training.
PRIOR ART CITATIO5 NS
PATENT CITATION
[0003] Patent Citation 1: PCT publication No. 2012/117488
SUMMARY OF INVENTION
10 TECHNICAL PROBLEM
[0004] The training apparatus as disclosed in Patent Citation 1, mainly in a case where a
person who undergoes a training trains a limb, for example, an upper limb to be trained in
accordance with a training program, monitors whether or not the movement of the upper limb
is following the movement of the training rod, and teaches the movement of the training rod
15 to the user of the training apparatus, as necessary, on the basis of visual or auditory
information. In this case, the conventional training apparatus evaluates whether or not the
movement of the upper limb is following the movement of the training rod instructed by the
training program, by a calculation operation inside the apparatus, for example, on the basis of
only a level of difference (a position difference) between an angle to tilt the training rod
20 instructed by the training program and an actual tilt angle of the training rod. However, by
only this evaluation method based on a level of position difference, the following status
change of the position difference may not appropriately be evaluated.
4
[0005] In the training apparatus for training a limb, as the state in which the limb is
following a movement instructed by the preset training program in the training apparatus (a
following status), there are following three states.
(i) The training rod moving the limb is operated in a state where a tilt angle of the
training rod is the same as that instructed by the training program (a state where the positio5 n
difference is zero).
(ii) The training rod is operated in a state where the tilt angle change of the training
rod per unit time is the same as a tilt angle change of the training rod instructed by the
training program (a state where the position difference is not zero but is a constant value
10 without change).
(iii) The training rod is operated in a state where the tilt angle of the training rod is
gradually shifted from a tilt angle of the training rod instructed by the training program (a
state where the position difference is gradually changed).
[0006] When evaluating the following status on the basis of only a level of the position
15 difference, the following status can be evaluated in the case (i) described above, while the
following status may not be correctly evaluated in the case (ii) or (iii) described above. For
instance, if the position difference is not changed and is a predetermined value or larger, or if
the position difference is gradually changing and becomes a predetermined value or larger,
the limb movement is evaluated to be following the training program although some delay
20 exists due to the position difference.
On the other hand, if the following status is evaluated on the basis of only a level of
the position difference without considering a temporal change, in some cases of a level of the
5
position difference, the limb movement is evaluated not to be following the training program
even in the case (ii) or (iii), and hence a state of the patient corresponding to the status of the
training rod cannot be appropriately monitored.
[0007] In other words, if the following status of the training rod is evaluated on the basis of
only a level of the position difference, an operating status of the training rod operated by 5 the
patient cannot be appropriately determined, which is, for example, a following status in
which the position difference is not zero but is not changed (a state where a constant load is
applied while the training rod is moving at a constant speed), or a following status in which
the position difference changes gradually (a state where the position difference gradually
10 increases as the training rod approaches a target point). For this reason, the state of the
patient cannot be appropriately monitored.
[0008] Accordingly, it is an object of the present invention to provide a training apparatus
for rehabilitation support, which appropriately determines the following status where the
position difference is not zero but is not changed, or the following status where the position
15 difference gradually changes, and controls the training rod so that training of a limb is
continued in the two following statuses if it is determined that the training can be continued
as a result of the determination.
TECHNICAL SOLUTION
20 [0009] As means for solving the problem, a plurality of embodiments are described below.
These embodiments can be arbitrarily combined as necessary.
A training apparatus according to an aspect of the present invention is a training
6
apparatus for training upper and/or lower limbs of a user in accordance with a predetermined
training program. The training apparatus includes a fixed frame, a training rod, a motor, a
rotation information detection sensor, a tilt angle calculation unit, a position difference
calculation unit, a determination unit, a motor drive unit, and a position difference
eliminating unit. The fixed frame is placed on or in the vicinity of a floor. The trainin5 g
rod is supported by the fixed frame in a manner capable of tilting about a predetermined
tilting axis with at least one degree of freedom. In addition, the training rod holds a limb.
The motor tilts the training rod about the tilting axis. The rotation information detection
sensor outputs an amount of rotation of the motor. The tilt angle calculation unit calculates
10 a tilt angle of the training rod on the basis of the amount of rotation of the motor. The
position difference calculation unit calculates a position difference at an interval of a
predetermined first time period. The position difference is a difference between an actual
tilt angle of the training rod and an instructed tilt angle of the training rod instructed by the
training program. The determination unit obtains the position difference calculated by the
15 position difference calculation unit every time when a predetermined second time period
elapses. Further, the determination unit determines whether or not a position difference
change amount generated in the second time period is the first threshold or lower. The
motor drive unit drives the motor so that the position difference is accumulated and
maintained if the determination unit determines that the position difference change amount
20 generated in the second time period is the first threshold or lower. The position difference
eliminating unit resets the accumulated and maintained position difference at a preset timing.
[0010] In this way, the determination unit obtains the position difference every time when
7
the unit time (the second time period) elapses. In this way, the position difference change
amount generated in the unit time (the second time period) can be calculated. In addition,
the determination unit determines whether or not the position difference change amount
generated in the unit time (the second time period) is the first threshold or lower. In this
way, the determination unit can appropriately determine occurrence of the following 5 status
where the position difference is not zero but is not changed, or occurrence of the following
status where the position difference is gradually changing.
Further, the position difference eliminating unit resets the accumulated and
maintained position difference at a predetermined timing. In this way, when the position
10 difference generated in the state where the position difference is not zero but is not changed,
or the position difference generated in the state where the position difference gradually
changes is increased, it is avoided that the determination unit determines an error. As a
result, the patient can continue the training of a limb using this training apparatus.
[0011] The training rod may be capable of expanding and contracting in a longitudinal axis
15 direction. Here, the longitudinal axis direction is a longitudinal direction of the training rod.
Because the training rod is capable of expanding and contracting in a longitudinal axis
direction, training of an upper limb or a lower limb can be carried out also in the longitudinal
direction of the training rod.
[0012] The determination unit may determine an error if the position difference change
20 amount generated in the second time period is higher than the first threshold. In this way, it
is possible to appropriately determine that the limb cannot follow the training program by
predicting a potential abnormality in this training apparatus and/or a potential obstacle that
8
may affect continuation of the training.
[0013] The training apparatus may further include an information providing unit. The
information providing unit provides visual or auditory information to a user including a
patient, a training aid, and a health care worker, when the determination unit determines that
an error has occurre5 d.
In this way, the user can be informed of a status of the training apparatus and/or a
potential obstacle that may affect continuation of the training.
[0014] The information providing unit may provide the information to the user when the
patient has moved the training rod to reach a preset passing point in a training route set by the
10 training program. In this way, the user can know that the training rod has been moved just
in accordance with the training program. In addition, because the user is provided with the
visual or auditory information when the patient has moved the training rod to reach the preset
passing point, the patient can maintain motivation to continue the training.
[0015] When the determination unit determines that an error has occurred, rotation of the
15 motor may be stopped. In this way, when an error has occurred, i.e., when it is determined
that there is a potential obstacle that may affect continuation of the training, the training
apparatus can be safely stopped.
[0016] The determination unit may further obtain the position difference every time when a
predetermined third time period elapses. Further, the determination unit may determine
20 whether or not the position difference change amount generated in the third time period is a
second threshold or lower. Further, when the determination unit determines that the position
difference change amount generated in the third time period is the second threshold or lower,
9
the position difference eliminating unit may reset the accumulated and maintained position
difference.
In this way, the accumulated and maintained position difference can be reset so that
the patient can continue the training without always performing the motor control (position
control) such that the actual tilt angle of the training rod follows the tilt angle instructed b5 y
the training program (instructed tilt angle).
[0017] The position difference eliminating unit may reset the accumulated and maintained
position difference when the operation of the training rod is stopped. In this way, the
position difference generated in the present training is not carried over to the next training
10 and after, and hence the patient can continue the training.
[0018] The training apparatus may further include an instruction generation unit. The
instruction generation unit generates a speed instruction including at least an acceleration
instruction for accelerating the motor and a deceleration instruction for decelerating the motor
in accordance with the training program. In this case, the motor drive unit may control the
15 motor so as to follow only the speed instruction when the acceleration instruction is executed.
Because the speed instruction including at least the acceleration instruction and the
deceleration instruction for driving the motor, the motor can be smoothly operated. As a
result, the patient can operate the training rod as intended.
In addition, because the motor drive unit drives the motor so as to follow only the
20 speed instruction when the acceleration instruction is executed, the motor can be controlled
so that the position difference is accumulated and maintained. As a result, the patient can
continue the training of the limb using the training apparatus even if the training rod is
10
operated at a large tilt angle, for example, in which a relatively large motor torque is required,
and a position difference is apt to occur. Further, because the position difference is
accumulated and maintained, a state of the limb during the training can be monitored on the
basis of the accumulated and maintained amount of the position difference.
[0019] The speed instruction may further include a constant speed instruction for rotati5 ng
the motor at a constant speed disposed between the acceleration instruction and the
deceleration instruction. In this case, the motor drive unit may control the motor so as to
follow only the speed instruction when the constant speed instruction is executed.
Because the speed instruction further includes the constant speed instruction, even if
10 the training rod is operated at a large tilt angle, the motor can be smoothly operated at a
constant speed on the basis of feedback current from the motor. In addition, because the
motor drive unit controls the motor so as to follow only the speed instruction when the
constant speed instruction is executed, the motor can be controlled so that the position
difference is accumulated and maintained. As a result, the patient can continue the training
15 of the limb using the training apparatus even if the training rod is operated at a large tilt angle,
for example, in which a relatively large motor torque is required, and a position difference is
apt to occur. In addition, when the motor is rotated at a constant speed, it is possible to
continue the training of the limb by a constant speed movement. Further, because the
position difference is accumulated and maintained, a state of the limb of the patient during
20 the training can be monitored on the basis of the accumulated and maintained amount of the
position difference.
[0020] The instruction generation unit may further generate a position instruction for
11
controlling the tilt angle of the training rod in accordance with the training program. In
addition, the motor drive unit may control the motor so as to follow the speed instruction and
the position instruction when the deceleration instruction is executed.
In this way, the motor drive unit can control the motor so that the training rod
reaches a target tilt angle instructed by the training program with a difference as small a5 s
possible. As a result, when the position information of the training rod is fed back as visual
information to the patient, for example, this position information can be appropriately used.
[0021] When the deceleration instruction is started, the position difference eliminating unit
may reset the accumulated and maintained position difference. Here, the reset of the
10 accumulated and maintained position difference means to set the accumulated and maintained
position difference to zero. In this way, when the deceleration instruction is executed, it is
possible to prevent the motor speed from being changed excessively by the position
instruction.
15 ADVANTAGEOUS EFFECTS
[0022] According to the present invention, it is possible to appropriately determine the
following status where the position difference is not zero but is not changed, or the following
status where the position difference gradually changes. In addition, it is possible to provide
the training apparatus for rehabilitation support that controls the training rod so as to continue
20 the training of the limb if it is determined that the training can be continued in the two
following statuses as a result of the determination.
12
BRIEF DESCRIPTION OF DRAWINGS
[0023] Fig. 1 is a diagram schematically illustrating a training apparatus.
Fig. 2 is a diagram illustrating an overall structure of a control unit and a training rod
tilt mechanism in a fixed frame.
Fig. 3 is a diagram illustrating a structure of a training 5 rod.
Fig. 4 is a diagram illustrating an overall structure of the control unit.
Fig. 5A is a graph illustrating a triangular speed locus type speed instruction.
Fig. 5B is a graph illustrating a trapezoidal speed locus type speed instruction.
Fig. 6 is a graph illustrating a position instruction.
10 Fig. 7 is a diagram illustrating a structure of a motor control unit.
Fig. 8 is a diagram illustrating a structure of a motor drive unit.
Fig. 9 is a flowchart illustrating a basic operation of the training apparatus.
Fig. 10 is a flowchart illustrating a method of controlling a motor.
Fig. 11 is a diagram illustrating a manner in which a speed difference is canceled,
15 while a position difference is accumulated and maintained.
Fig. 12 is a flowchart illustrating a method of determining whether or not a position
difference change amount is within an allowable range.
Fig. 13A is a flowchart illustrating a method of determining whether or not the
position difference change amount generated in a third time period is a second threshold or
20 lower.
Fig. 13B is a flowchart illustrating a method of determining whether or not operation
of the training rod is stopped.
13
Fig. 13C is a flowchart illustrating a method of determining whether or not a tilt
angle of the training rod has reached a deceleration start position.
Fig. 14A is a flowchart illustrating a method of physically resetting the position
difference.
Fig. 14B is a flowchart illustrating an example of a method of resetting the positi5 on
difference by setting a position difference value as a parameter to zero.
Fig. 15A is a graph schematically illustrating a method of resetting the position
difference by the method of physically resetting the position difference.
Fig. 15B is a graph schematically illustrating an example of a method of resetting
10 the position difference by setting the position difference value as a parameter to zero.
Fig. 15C is a graph schematically illustrating a manner in which when the position
instruction is shifted in parallel with respect to the time axis, the speed instruction is also
shifted in parallel with respect to the time axis.
15 DESCRIPTION OF EMBODIMENTS
[0024] 1. First embodiment
(1) Overall structure of training apparatus
An overall structure of a training apparatus 100 according to a first embodiment is
described with reference to Fig. 1. Fig. 1 is a diagram schematically illustrating the training
20 apparatus 100. The training apparatus 100 is a training apparatus for carrying out training
aimed at motor function recovery of an upper limb and/or a lower limb of a user (a patient) in
accordance with a predetermined training program.
14
The training apparatus 100 includes mainly a fixed frame 1, a training rod 3, and a
training instruction unit 5. The fixed frame 1 is placed on or in the vicinity of a floor on
which the training apparatus 100 is installed. In addition, the fixed frame 1 constitutes a
main body casing of the training apparatus 100. The training rod 3 is attached to the fixed
frame 1 via a training rod tilt mechanism 13 (Fig. 2) disposed inside the fixed frame 1. As 5 a
result, the training rod 3 can be tilted by the training rod tilt mechanism 13 in an X-axis
direction parallel to a longitudinal direction of the fixed frame 1 and in a Y-axis direction
parallel to a width direction of the fixed frame 1 (Figs. 1 and 2).
Note that the training rod 3 may be capable of tilting only in the X-axis direction or
10 the Y-axis direction, as necessary. In this case, the training rod 3 can tilt with one degree of
freedom.
In addition, the training rod 3 may include inside an expansion/contraction
mechanism in the longitudinal axis direction of the training rod 3 (Fig. 3). In this case, the
training rod 3 can expand and contract in the longitudinal direction of the training rod 3, and
15 hence can form a movement with at least 2 degrees of freedom or 3 degrees of freedom in
cooperation with the training rod tilt mechanism 13.
[0025] In addition, the training rod 3 includes a limb support member 31 (described later)
disposed on an upper end portion of the training rod 3. When the limb of the patient is
supported by the limb support member 31, the training rod 3 can move the limb of the patient.
20 Alternatively, the patient can move the training rod 3 by his/her intention.
[0026] The training instruction unit 5 is fixed to the fixed frame 1 via a fixing member 7.
The training instruction unit 5 executes a preset training program and transmits a training rod
15
operation instruction to a control unit 11 (Fig. 2), for operating the training rod 3, as
necessary. In addition, the training instruction unit 5 provides a training route and an actual
training movement of the limb of the patient as visual or auditory information by the preset
training program. In this way, the patient can carry out the training of the limb while
feeding back the training movement set by the training program and the actual move5 ment.
Further, also when the limb of the patient tilted the training rod 3 to a target point (a
target tilt angle) indicated by the training program, the training instruction unit 5 may inform
the user with visual or auditory information that the training rod 3 has reached the target tilt
angle. In this way, the patient can maintain motivation to continue the training.
10 [0027] In addition, when a determination unit 1134 described later (Fig. 7) determines that
an error has occurred, the training instruction unit 5 provides the user with visual or auditory
information. In this way, the user can be informed of a status of the training apparatus 100,
and/or that there is a potential obstacle that may affect continuation of the training.
[0028] As the training instruction unit 5, an integrated computer system can be used, which
15 includes a display device such as a liquid crystal display, a central processing unit (CPU), a
storage device such as a random access memory (RAM), a read only memory (ROM), a hard
disk and a solid state drive (SSD), and an input device such as a touch panel as necessary.
In addition, the training instruction unit 5 may be constituted of a separate display device and
other computer system. In this case, only the display device is fixed to the fixed frame 1 via
20 the fixing member 7.
[0029] The training program executed by the training instruction unit 5 has five training
modes, for example, including (i) guided mode, (ii) initiated mode, (iii) step initiated mode,
16
(iv) follow assist mode, and (v) free mode. The guided mode is a training mode in which
the training rod 3 moves the limb in a predetermined direction at a constant speed regardless
of a movement of the limb of the patient. The initiated mode is a training mode in which a
force that the patient intends to move the training rod 3 by the limb in a correct direction at an
initial movement position with respect to the training route preset by the training progra5 m
(also referred to as a force sensing trigger) is detected, and the training rod 3 moves the limb
of the patient in a direction of the predetermined training route at a constant speed. The step
initiated mode is a training mode in which the training rod 3 moves the limb of the patient by
a constant distance in the training route when detecting the force sensing trigger at a
10 predetermined point in the training route of the training rod 3. The follow assist mode is a
training mode in which the force sensing trigger is detected every predetermined period, and
a speed of the training rod 3 is changed in accordance with a level of the detected force
sensing trigger. The free mode is a training mode in which the training rod 3 is moved so as
to follow a movement of the limb of the patient.
15 [0030] In addition, the training apparatus 100 may further include a chair 9 for the patient to
sit during the training. The chair 9 is connected to the fixed frame 1 via a chair connecting
member 91, and hence stability of the training apparatus 100 can be secured. In addition,
because the chair connecting member 91 is fixed with good reproductivity, the patient can
carry out the training every time at the same position.
20 [0031] (2) Structure of control unit and training rod tilt mechanism
I. Overall structure
Next, an overall structure of the control unit 11 and the training rod tilt mechanism
17
13 is described with reference to Fig. 2. Fig. 2 is a diagram illustrating an overall structure
of the control unit 11 and the training rod tilt mechanism 13 disposed in the fixed frame 1.
The control unit 11 and the training rod tilt mechanism 13 are disposed in the fixed
frame 1. The control unit 11 is connected to the training instruction unit 5 in a manner
capable of transmitting and receiving signals. The control unit 11 receives the training 5 rod
operation instruction transmitted from the training instruction unit 5. In addition, the control
unit 11 is electrically connected to an X-axis direction tilt motor 135b (described later), a
Y-axis direction tilt motor 135a (described later), and an expansion/contraction motor 359
(Fig. 3). Accordingly, the control unit 11 drives the above-mentioned three motors on the
10 basis of the training rod operation instruction. Note that structure and operation of the
control unit 11 will be described later in detail.
The training rod tilt mechanism 13 is attached to the fixed frame 1 in a manner
capable of tilting via training rod tilt mechanism fixing members 15a and 15b fixed to the
fixed frame 1. For this reason, the training rod tilt mechanism 13 can tilt the training rod 3
15 in the X-axis direction and in the Y-axis direction (with 2 degrees of freedom). Hereinafter,
a structure of the training rod tilt mechanism 13 is described in detail.
Note that the training rod tilt mechanism 13 may be configured to tilt the training
rod 3 only in the X-axis direction or in the Y-axis direction (with one degree of freedom).
Alternatively, the training rod tilt mechanism 13 may be selectable whether to tilt the training
20 rod 3 with one degree of freedom or with 2 degrees of freedom.
[0032] II. Structure of training rod tilt mechanism
The structure of the training rod tilt mechanism 13 of this embodiment is described
18
with reference to Fig. 2. The training rod tilt mechanism 13 enables to tilt the training rod 3
in the X-axis direction and in the Y-axis direction by a "gimbal" mechanism that enables to
move two axes. Here, the X-axis direction is a horizontal direction parallel to the
longitudinal direction of the fixed frame 1 in Fig. 2. The Y-axis direction is a horizontal
direction parallel to the width direction of the fixed frame 1 in Fig. 5 . 2.
The training rod tilt mechanism 13 includes an X-axis direction tilt member 131 and
a Y-axis direction tilt member 133 (described later), as well as the X-axis direction tilt motor
135b and the Y-axis direction tilt motor 135a respectively corresponding to the tilt members.
Further, when the training rod tilt mechanism 13 tilts the training rod 3 with one
10 degree of freedom, it is sufficient that the training rod tilt mechanism 13 includes only the
X-axis direction tilt member 131 and the X-axis direction tilt motor 135b, or the Y-axis
direction tilt member 133 and the Y-axis direction tilt motor 135a. Alternatively, even if the
training rod tilt mechanism 13 includes the above-mentioned two members and two motors,
the training rod tilt mechanism 13 can tilt the training rod 3 with one degree of freedom by
15 disabling one combination of the member and the motor.
[0033] The X-axis direction tilt member 131 is disposed inside a space of the Y-axis
direction tilt member 133. In addition, the X-axis direction tilt member 131 includes two
shafts 131a and 131b extending outward from two side surfaces having normals parallel to
the Y-axis. The two shafts 131a and 131b are supported respectively by the two side
20 surfaces having normals parallel to the Y-axis of the Y-axis direction tilt member 133 in a
manner capable of rotating the X-axis direction tilt member 131 about the Y-axis. In this
way, the X-axis direction tilt member 131 can change an angle between the training rod 3
19
fixed to the X-axis direction tilt member 131 and the X-axis. Here, changing the angle
between the training rod 3 and the X-axis may be referred to as "tilting in the X-axis
direction".
Note that the training rod 3 is fixed to the X-axis direction tilt member 131 in a state
where a part of the training rod 3 is inserted in a space S of the X-axis direction tilt 5 member
131.
[0034] In the same manner, the Y-axis direction tilt member 133 includes two shafts 133a
and 133b extending outward from two side surfaces having normals parallel to the X-axis.
The two shafts 133a and 133b are supported respectively by the training rod tilt mechanism
10 fixing members 15a and 15b in a manner capable of rotating the Y-axis direction tilt member
133 about the X-axis. In this way, the Y-axis direction tilt member 133 can rotate about the
X-axis with respect to the training rod tilt mechanism fixing members 15a and 15b. As a
result, the Y-axis direction tilt member 133 can change an angle between the training rod 3
fixed to the X-axis direction tilt member 131 and the Y-axis. Here, changing the angle
15 between the training rod 3 and the Y-axis may be referred to as "tilting in the Y-axis
direction".
[0035] In this way, the Y-axis direction tilt member 133 tilts the training rod 3 in the Y-axis
direction, and the X-axis direction tilt member 131 tilts the training rod 3 in the X-axis
direction. Accordingly, the training rod tilt mechanism 13 can tilt the training rod 3 with
20 two-dimensional degrees of freedom. Further, although the X-axis direction tilt member
131 is disposed inside the space of the Y-axis direction tilt member 133 in Fig. 2, it is
possible to modify the design so that the X-axis direction tilt member 131 is disposed outside
20
the space of the Y-axis direction tilt member 133 so as to tilt the corresponding member.
[0036] The Y-axis direction tilt motor 135a is fixed to the training rod tilt mechanism fixing
member 15a. In addition, an output rotation shaft of the Y-axis direction tilt motor 135a is
connected, via a speed reduction mechanism (not shown), to the shaft 133a extending from
the Y-axis direction tilt member 133 so as to rotate the shaft 133a. Accordingly, the Y-ax5 is
direction tilt motor 135a rotates the Y-axis direction tilt member 133 about the X-axis.
Further, the Y-axis direction tilt motor 135a is electrically connected to the control unit 11.
Accordingly, the Y-axis direction tilt motor 135a can tilt the training rod 3 in the Y-axis
direction by control by the control unit 11.
10 [0037] The X-axis direction tilt motor 135b is fixed to the surface that pivotally supports a
shaft 131a extending from the X-axis direction tilt member 131, among four side surfaces of
the Y-axis direction tilt member 133. In addition, an output rotation shaft of the X-axis
direction tilt motor 135b is connected to the shaft 131a extending from the X-axis direction
tilt member 131 via a speed reduction mechanism (not shown) so as to rotate the shaft 131a.
15 Accordingly, the X-axis direction tilt motor 135b can rotate the X-axis direction tilt member
131 about the Y-axis. Further, the X-axis direction tilt motor 135b is electrically connected
to the control unit 11. Accordingly, the X-axis direction tilt motor 135b can tilt the training
rod 3 in the X-axis direction by control by the control unit 11.
[0038] In this way, the Y-axis direction tilt motor 135a and the X-axis direction tilt motor
20 135b tilt the training rod 3 respectively in the X-axis direction and in the Y-axis direction
with one degree of freedom by control by the control unit 11. In other words, because the
X-axis direction tilt motor 135b and the Y-axis direction tilt motor 135a are provided, the
21
training rod 3 can be controlled in a two-dimensional manner.
[0039] As the Y-axis direction tilt motor 135a and the X-axis direction tilt motor 135b, an
electric motor such as a servo motor or a brush-less motor can be used, for example.
[0040] (3) Structure of training rod
I. Overall 5 structure
Next, a structure of the training rod 3 is described with reference to Fig. 3. First, an
overall structure of the training rod 3 is described. Fig. 3 is a diagram illustrating a structure
of the training rod 3. The training rod 3 includes the limb support member 31, a fixed stay
33, and an expansion/contraction mechanism 35. The limb support member 31 is fixed to
10 an upper end portion of a cover 353 (described later) of the expansion/contraction mechanism
35. The limb support member 31 is a member supporting the limb of the patient. The
fixed stay 33 constitutes a main body of the training rod 3. In addition, the fixed stay 33 has
a space S' for housing a movable stay 351 (described later) of the expansion/contraction
mechanism 35. Further, the fixed stay 33 includes a fixing member (not shown) for fixing
15 the training rod 3 to the X-axis direction tilt member 131 of the training rod tilt mechanism
13. When the fixed stay 33 is fixed to the X-axis direction tilt member 131 with the fixing
member of the fixed stay 33, the training rod 3 is fixed to the training rod tilt mechanism 13.
[0041] The expansion/contraction mechanism 35 is provided to the fixed stay 33 in a
movable manner along the longitudinal direction of the fixed stay 33. In this way, the
20 training rod 3 can expand and contract in the longitudinal direction of the training rod 3.
Hereinafter, a structure of the expansion/contraction mechanism 35 is described in detail.
[0042] II. Structure of expansion/contraction mechanism
22
As illustrated in Fig. 3, the expansion/contraction mechanism 35 includes the
movable stay 351, the cover 353, a nut 355, a threaded shaft 357, and the
expansion/contraction motor 359.
The movable stay 351 is inserted in the space S' formed in the fixed stay 33. In
addition, the movable stay 351 includes a slide unit (not shown). This slide unit is slidabl5 y
engaged with a guide rail 37 provided on an inner wall of the fixed stay 33. As a result, the
movable stay 351 can move along the guide rail 37 in the space S' formed in the fixed stay 33.
The cover 353 is fixed to the upper end portion of the movable stay 351. In this way, the
cover 353 can move in accordance with movement of the movable stay 351. In addition, the
10 cover 353 includes the limb support member 31 on the upper end portion. Accordingly, the
cover 353 can move the limb support member 31 in the extending direction of the fixed stay
33.
[0043] The nut 355 is attached to a bottom portion of the movable stay 351. The nut 355
is engaged with the threaded shaft 357 (described later). The threaded shaft 357 is a thread
15 member elongated in parallel to the longitudinal direction of the fixed stay 33. In addition,
the threaded shaft 357 is engaged with the nut 355. Accordingly, when the threaded shaft
357 rotates, the nut 355 moves along the longitudinal direction of the threaded shaft 357
(namely, the longitudinal direction of the fixed stay 33 (the longitudinal axis direction)).
As described above, because the nut 355 is fixed to the bottom portion of the
20 movable stay 351, when the nut 355 moves along the extending direction of the threaded
shaft 357, the movable stay 351 can move along the longitudinal direction of the fixed stay
33.
23
[0044] The expansion/contraction motor 359 is fixed to a bottom portion of the fixed stay
33. In addition, an output rotation shaft of the expansion/contraction motor 359 is
connected to an end portion in the longitudinal direction of the threaded shaft 357 so as to
rotate the threaded shaft 357 about the axis. Further, the expansion/contraction motor 359 is
electrically connected to the control unit 11. Accordingly, the expansion/contraction mot5 or
359 can rotate the threaded shaft 357 about the axis of the threaded shaft 357 by control by
the control unit 11.
As described above, the nut 355 is engaged with the threaded shaft 357, and hence
the nut 355 can move along the longitudinal direction of the threaded shaft 357 in accordance
10 with rotation of the threaded shaft 357. Accordingly, the movable stay 351 can move along
the longitudinal direction of the fixed stay 33 (longitudinal axis direction) in accordance with
rotation of the expansion/contraction motor 359.
[0045] (4) Structure of control unit
I. Overall structure
15 Next, an overall structure of the control unit 11 is described with reference to Fig. 4.
Fig. 4 is a diagram illustrating an overall structure of the control unit 11. As the control unit
11, it is possible to use a microcomputer system, for example, which includes a CPU, a
storage device such as a RAM, a ROM, a hard disk drive, and an SSD, an interface for
converting an electric signal, and the like. In addition, a part or a whole of functions of the
20 control unit 11 described below may be realized by a program that can be executed by the
microcomputer system. In addition, the program may be stored in the storage device of the
microcomputer system. Further, a part or a whole of functions of the control unit 11 may be
24
realized by a custom IC or the like.
The control unit 11 includes an instruction generation unit 111, and motor control
units 113a, 113b, and 113c.
[0046] The instruction generation unit 111 is connected to the training instruction unit 5 and
the motor control units 113a, 113b, and 113c in a manner capable of transmitting a5 nd
receiving signals. The instruction generation unit 111 generates instructions for the motor
control units 113a, 113b, and 113c to respectively drive the Y-axis direction tilt motor 135a,
the X-axis direction tilt motor 135b, and the expansion/contraction motor 359 on the basis of
the training rod operation instruction transmitted from the training instruction unit 5.
10 [0047] The instructions generated by the instruction generation unit 111 include a speed
instruction and a position instruction. The speed instruction is an instruction for controlling
rotation speed of the motor (an amount of change of the tilt angle or the
expansion/contraction length of the training rod 3 per unit time). In addition, the position
instruction is an instruction for controlling the tilt angle or the expansion/contraction length
15 of the training rod 3.
As described later, when each of the motor control units 113a, 113b, and 113c
controls each of the motors on the basis of the speed instruction, the motor is controlled to
follow the speed instructed by the speed instruction. In other words, if there is a difference
(speed difference) between the speed instructed by the speed instruction and the actual
20 rotation speed of the motor, each of the motor control units 113a, 113b, and 113c controls the
motor so as to eliminate the speed difference.
[0048] On the other hand, when each of the motor control units 113a, 113b, and 113c
25
controls the motor on the basis of the position instruction, the motor is controlled to allow the
tilt angle or the expansion/contraction length of the training rod 3 to follow the tilt angle
instructed by the position instruction (instructed tilt angle) or the expansion/contraction
length instructed by the position instruction (instructed expansion/contraction length). In
other words, if there is a difference (position difference) between the tilt angle instructed b5 y
the position instruction and the actual tilt angle of the training rod 3, or between the
expansion/contraction length instructed by the position instruction and the actual
expansion/contraction length of the training rod 3, each of the motor control units 113a, 113b,
and 113c controls the motor so as to eliminate the position difference.
10 [0049] Note that the speed instruction and the position instruction generated by the
instruction generation unit 111 are functions of time. On the other hand, the training rod
operation instruction transmitted from the training instruction unit 5 includes at least
information of the tilt angle to which the training rod 3 is moved (target position information)
and information of the amount of change of the tilt angle or the expansion/contraction length
15 of the training rod 3 per unit time (the tilt angle speed or the expansion/contraction length
speed) (target speed information), and further includes information of an acceleration rate for
the tilt angle speed of the training rod 3 or the expansion/contraction length speed to reach a
desired tilt angle speed or expansion/contraction length speed (acceleration rate information)
and information of a deceleration rate for stopping the moving training rod 3 (deceleration
20 rate information).
[0050] In other words, the training rod operation instruction as a base for generating the
speed instruction and the position instruction does not include information of time.
26
However, the training rod operation instruction includes information of distance
(corresponding to the target position information) and information of speed (corresponding to
the target speed information), and further includes information of acceleration rate
(corresponding to the acceleration rate information and the deceleration rate information).
Accordingly, the information of time can be derived from these informatio5 n.
Thus, the instruction generation unit 111 can generate the speed instruction and the
position instruction as functions of time, by calculating with appropriate combination of the
target position information and the target speed information, as well as the acceleration rate
information and the deceleration rate information, included in the training rod operation
10 instruction.
[0051] In addition, the speed instructions generated by the instruction generation unit 111
include two types of speed instructions as illustrated in Figs. 5A and 5B. One of them is the
speed instruction as illustrated in Fig. 5A, which includes only an acceleration instruction for
accelerating the motor at a constant acceleration rate and a deceleration instruction for
15 decelerating the motor at a constant deceleration rate. This speed instruction can be
expressed as a graph having a triangular shape in a coordinate system in which the horizontal
axis represents time, while the vertical axis represents speed. Accordingly, this speed
instruction may be referred to as a triangular speed locus type speed instruction. The case
where the speed instruction becomes the triangular speed locus type is, for example, a case
20 where a moving distance of the training rod 3 is short when moving from a current tilt angle
of the training rod 3 to a target tilt angle of the training rod 3 instructed by the training
instruction unit 5, a case where the acceleration rate or the deceleration rate of the motor
27
instructed by the training rod operation instruction is small, or the like.
In this way, because the speed instruction include the acceleration instruction and the
deceleration instruction, the motor control units 113a, 113b, and 113c can smoothly control
the motors.
[0052] The other type is the speed instruction as illustrated in Fig. 5B, which includes, 5 ludes, in
addition to the acceleration instruction and the deceleration instruction, a constant speed
instruction for rotating the motor at a constant speed. This speed instruction can be
expressed as a graph having a trapezoidal shape in a coordinate system in which the
horizontal axis represents time, while the vertical axis represents speed. Accordingly, this
10 speed instruction may be referred to as a trapezoidal speed locus type speed instruction. The
case where the speed instruction becomes the trapezoidal speed locus is, for example, a case
where a moving distance of the training rod 3 is long when moving from a current tilt angle
of the training rod 3 to a target tilt angle of the training rod 3 instructed by the training
instruction unit 5, a case where the acceleration rate or the deceleration rate of the motor is
15 large, or the like.
In this way, because the speed instruction further include the constant speed
instruction, the motor control units 113a, 113b, and 113c can smoothly control the motors
even if the training rod 3 moves at a large tilt angle.
[0053] On the other hand, the position instruction generated by the instruction generation
20 unit 111 has a shape as illustrated in Fig. 6 in a coordinate system in which the horizontal axis
represents time, while the vertical axis represents position (tilt angle). The position
instruction corresponds to an integrated value of the speed instruction over time. The
28
position instruction illustrated in Fig. 6 is a position instruction corresponding to the
trapezoidal speed locus type speed instruction illustrated in Fig. 5B. Accordingly, in the
trapezoidal speed locus type speed instruction, the position instruction has a
downward-convex parabola shape with a vertex at time point 0 in a period between time
points 0 to t1 (during an acceleration instruction interval) while the speed increases with 5 a
positive gradient. In a period between time points t1 and t2 (a constant speed instruction
interval) until the speed becomes a line parallel to a horizontal axis in the speed instruction,
the position instruction increases linearly with a positive gradient. Further, in a period
between time points t2 and t3 (during a deceleration instruction interval) while the speed
10 decreases with a negative gradient in the speed instruction, the position instruction has an
upward-convex parabola shape with a vertex at time point t3.
[0054] The motor control units 113a, 113b, and 113c are connected to the instruction
generation unit 111 in a manner capable of transmitting and receiving signals. Accordingly,
the motor control units 113a, 113b, and 113c can receive the speed instruction and the
15 position instruction from the instruction generation unit 111. In addition, the motor control
units 113a, 113b, and 113c are electrically connected to the Y-axis direction tilt motor 135a,
the X-axis direction tilt motor 135b, and the expansion/contraction motor 359, respectively.
Accordingly, the motor control units 113a, 113b, and 113c can control the motors in
accordance with the speed instruction and/or the position instruction.
20 Further, the motor control units 113a, 113b, and 113c are connected to a first rotation
information detection sensor 135a-1 for the Y-axis direction tilt motor 135a, a second rotation
information detection sensor 135b-1 for the X-axis direction tilt motor 135b, and a third
29
rotation information detection sensor 359-1 for the expansion/contraction motor 359,
respectively, in a manner capable of transmitting and receiving signals.
[0055] The first rotation information detection sensor 135a-1, the second rotation
information detection sensor 135b-1, and the third rotation information detection sensor
359-1 are fixed to the output rotation shaft of the Y-axis direction tilt motor 135a, the 5 output
rotation shaft of the X-axis direction tilt motor 135b, and the output rotation shaft of the
expansion/contraction motor 359, respectively. In this way, the first rotation information
detection sensor 135a-1, the second rotation information detection sensor 135b-1, and the
third rotation information detection sensor 359-1 can output an amount of rotation of the
10 Y-axis direction tilt motor 135a, an amount of rotation of the X-axis direction tilt motor 135b,
and an amount of rotation of the expansion/contraction motor 359, respectively.
As the first rotation information detection sensor 135a-1, the second rotation
information detection sensor 135b-1, and the third rotation information detection sensor
359-1, it is possible to use sensors that can measure an amount of rotation of the output
15 rotation shaft of the motor. As such the sensor, for example, an encoder such as an
incremental type encoder or an absolute type encoder can be appropriately used. When
encoders are used as the sensors, the first rotation information detection sensor 135a-1, the
second rotation information detection sensor 135b-1, and the third rotation information
detection sensor 359-1 output pulse signals corresponding to amounts of rotation of the
20 Y-axis direction tilt motor 135a, an amount of rotation of the X-axis direction tilt motor 135b,
and an amount of rotation of the expansion/contraction motor 359, respectively.
[0056] In this way, because the motor control units 113a, 113b, and 113c are connected to
30
the first rotation information detection sensor 135a-1, the second rotation information
detection sensor 135b-1, and the third rotation information detection sensor 359-1,
respectively, for measuring amounts of rotation of the output rotation shafts of the motors, the
motor control units 113a, 113b, and 113c can control the motors in consideration of actual
amounts of rotation of the motor5 s.
[0057] Next, the motor control units 113a, 113b, and 113c are described in detail. In the
following description, the motor control unit 113a is exemplified and described. It is
because other motor control units 113b and 113c have the same structure and the same
operation as the motor control unit 113a.
10 [0058] II. Structure of motor control unit
A structure of the motor control unit 113a is described with reference to Fig. 7. Fig.
7 is a diagram illustrating a structure of the motor control unit 113a.
The motor control unit 113a includes a tilt angle calculation unit 1131, a position
difference calculation unit 1132, a position difference eliminating unit 1133, the
15 determination unit 1134, and a motor drive unit 1135.
The tilt angle calculation unit 1131 is connected to the first rotation information
detection sensor 135a-1 in a manner capable of transmitting and receiving signals. In this
way, the pulse signal output corresponding to the amount of rotation of the output rotation
shaft of the Y-axis direction tilt motor 135a measured by the first rotation information
20 detection sensor 135a-1 can be input to the tilt angle calculation unit 1131. Further, the tilt
angle calculation unit 1131 calculates a tilt angle of the training rod 3 (in the Y-axis direction)
on the basis of the number of pulses included in the pulse signal output from the first rotation
31
information detection sensor 135a-1.
[0059] The position difference calculation unit 1132 is connected to the tilt angle
calculation unit 1131 in a manner capable of transmitting and receiving signals. In this way,
the tilt angle of the training rod 3 calculated by the tilt angle calculation unit 1131 is input to
the position difference calculation unit 1132. In addition, the position difference calculati5 on
unit 1132 is connected to the instruction generation unit 111 in a manner capable of
transmitting and receiving signals. In this way, the position instruction generated by the
instruction generation unit 111 is input to the position difference calculation unit 1132.
The position difference calculation unit 1132 calculates a difference between the
10 actual tilt angle of the training rod 3 calculated by the tilt angle calculation unit 1131 and the
tilt angle of the training rod 3 instructed by the position instruction (instructed tilt angle), as
the position difference, at an interval of a first time period T1. The first time period T1 as the
interval for calculating the position difference corresponds to a control interval for the motor
drive unit 1135 to control the Y-axis direction tilt motor 135a.
15 [0060] The position difference eliminating unit 1133 is connected to the position difference
calculation unit 1132 in a manner capable of transmitting and receiving signals. In this way,
the position difference is input to the position difference eliminating unit 1133 from the
position difference calculation unit 1132. In addition, the position difference eliminating
unit 1133 is connected to the determination unit 1134 in a manner capable of transmitting and
20 receiving signals. In this way, on the basis of a signal from the determination unit 1134, the
position difference eliminating unit 1133 can switch whether or not to perform correction of
the position difference. Further, the position difference eliminating unit 1133 is connected
32
to the instruction generation unit 111 in a manner capable of transmitting and receiving
signals. In this way, the position difference eliminating unit 1133 can receive the position
instruction from the instruction generation unit 111.
In addition, the position difference eliminating unit 1133 is connected to a position
control unit 1135-2 (Fig. 8) of the motor drive unit 1135 in a manner capable of transmitt5 ing
and receiving signals, as described later. In this way, the position difference eliminating unit
1133 can output the corrected position difference (reset position difference) to the position
control unit 1135-2.
[0061] At a preset timing, the position difference eliminating unit 1133 resets the
10 accumulated and maintained position difference output from the position difference
calculation unit 1132. In this embodiment, a timing for resetting the position difference is
set to (i) a timing when the determination unit 1134 determines that the position difference
change amount generated in a third time period T3 (described later) is a second threshold φ2
(described later) or lower, (ii) a timing when operation of the training rod 3 (the Y-axis
15 direction tilt motor 135a) is stopped, and/or, (iii) a timing when the tilt angle of the training
rod 3 has reached a deceleration start position (described later). The position difference
eliminating unit 1133 may reset the accumulated and maintained position difference at all the
three timings, or may reset the accumulated and maintained position difference at one or two
of the three timings.
20 Further, if any one of the timings (i) to (iii) is not applicable, the position difference
eliminating unit 1133 does not reset the accumulated and maintained position difference but
output the position difference output from the position difference calculation unit 1132, as it
33
is.
[0062] Among the three timings described above, the timing (i) can be detected on the basis
of a signal from the determination unit 1134. On the other hand, the timings (ii) and (iii) are
detected when the position difference eliminating unit 1133 detects the actual tilt angle of the
training rod 3. The position difference eliminating unit 1133 can detect the actual tilt ang5 le
of the training rod 3 by subtracting the position difference from the instructed tilt angle
instructed by the position instruction. However, without limiting to this, the position
difference eliminating unit 1133 may obtain the actual tilt angle of the training rod 3 directly
from the tilt angle calculation unit 1131.
10 [0063] In addition, the position difference eliminating unit 1133 resets the accumulated and
maintained position difference by the following two methods.
A first method includes temporarily connecting the position control unit 1135-2 of
the motor drive unit 1135 (Fig. 8) to the combining unit (described later) at the timing
described above, and temporarily controlling the Y-axis direction tilt motor 135a so that the
15 tilt angle of the training rod 3 follows the instructed tilt angle (the position control). In this
way, the actual tilt angle of the training rod 3 matches the instructed tilt angle. As a result,
the position difference is prevented from being excessively accumulated and maintained.
Further, the matching between the actual tilt angle of the training rod 3 and the
instructed tilt angle as a result of the control so that the tilt angle of the training rod 3 follows
20 the instructed tilt angle (the position control) may be referred to as "physical matching
between the actual tilt angle of the training rod 3 and the instructed tilt angle", or "physical
reset of the position difference".
34
A second method includes setting the position difference value as a parameter
handled by the control unit 11 to zero at the timing described above. In this method of
resetting the position difference, even if the position difference is reset, the position
difference between the actual tilt angle of the training rod 3 and the instructed tilt angle is
maintained. In this way, by setting the position difference value as a parameter to zero, 5 ro, a
level of the accumulated and maintained position difference (described later) is prevented
from being increased, and it is avoided to determine an error. In addition, as described later,
the position control unit 1135-2 is controlled on the basis of the corrected position difference
output from the position difference eliminating unit 1133. In this way, when the position
10 difference as the parameter is set to zero, a second control amount (described later) output
from the position control unit 1135-2 can be decreased. As a result, it is possible to prevent
a rotation speed of the Y-axis direction tilt motor 135a from being excessively increased on
the basis of an increase of the position difference. Accordingly, the training can be safely
continued.
15 [0064] The determination unit 1134 is connected to the position difference calculation unit
1132 in a manner capable of transmitting and receiving signals. Accordingly, the
determination unit 1134 can receive the position difference from the position difference
calculation unit 1132. In addition, the determination unit 1134 is connected to the position
difference eliminating unit 1133 and the motor drive unit 1135 (described later) in a manner
20 capable of transmitting and receiving signals. Accordingly, the determination unit 1134 can
determine an operation of the position difference eliminating unit 1133 and the motor drive
unit 1135 on the basis of whether or not the following first condition and/or second condition
35
are "true" or "false".
The determination unit 1134 obtains the position difference output from the position
difference calculation unit 1132, every time when a second time period T2 elapses. As
described later, because the position difference is obtained every time when the preset second
time period T2 elapses, the position difference change amount per unit time can be calculate5 d.
As a result, the determination unit 1134 can appropriately determine a case where a following
status in which the position difference is not zero but is not changed has occurred, or a case
where a following status in which the position difference gradually changes has occurred.
[0065] Further, the determination unit 1134 determines whether or not the position
10 difference change amount generated in the second time period T2 is a first threshold φ1 or
lower (first condition). Further, if the first condition is "true", the determination unit 1134
instructs the motor drive unit 1135 to drive the Y-axis direction tilt motor 135a so that the
position difference is accumulated and maintained.
On the other hand, if the determination unit 1134 determines that the first condition
15 is "false", an error is determined. If it is determined that the first condition is "false", the
determination unit 1134 instructs the motor control unit 113a to perform an error process. If
the first condition is "false", it means that the position difference has rapidly changed, and
further, it indicates that the limb of the patient cannot follow the set training program, which
may affect continuation of the training.
20 For this reason, if the first condition is "false", the error process is performed, and
the training apparatus 100 can be safely operated or stopped. As a result, the training can be
safely continued or finished.
36
[0066] In addition, the determination unit 1134 obtains the position difference output from
the position difference calculation unit 1132 every time when the third time period T3 elapses.
Further, the determination unit 1134 determines whether or not the position difference change
amount generated in the third time period T3 is the second threshold φ2 or lower (the second
condition). Further, if the second condition is "true", the determination unit 1134 instruc5 ts
the position difference eliminating unit 1133 to reset the position difference.
In this way, if the position difference change amount generated in the third time
period T3 is the second threshold φ2 or lower, the position difference eliminating unit 1133
can reset the position difference.
10 [0067] The motor drive unit 1135 is connected to the instruction generation unit 111 in a
manner capable of transmitting and receiving signals. In this way, the position instruction
and the speed instruction are input to the motor drive unit 1135 from the instruction
generation unit 111. In addition, the motor drive unit 1135 is electrically connected to the
Y-axis direction tilt motor 135a. Further, the motor drive unit 1135 is connected to the first
15 rotation information detection sensor 135a-1 in a manner capable of transmitting and
receiving signals.
In this way, the motor drive unit 1135 can control the Y-axis direction tilt motor 135a
on the basis of the speed instruction and/or the position instruction, and the amount of
rotation of the Y-axis direction tilt motor 135a. Details of the motor drive unit 1135 will be
20 described later.
[0068] III. Structure of motor drive unit
Next, a structure of the motor drive unit 1135 is described with reference to Fig. 8.
37
Fig. 8 is a diagram illustrating a structure of the motor drive unit. The motor drive unit 1135
includes a speed control unit 1135-1, the position control unit 1135-2, a speed calculation unit
1135-3, a power supply unit 1135-4 (described later), a difference calculation unit 1135-5
(described later), a combining unit 1135-6 (described later), and a switching unit 1135-7
(described later5 ).
The speed control unit 1135-1 is connected to the difference calculation unit 1135-5
in a manner capable of transmitting and receiving signals. Accordingly, the speed control
unit 1135-1 receives a difference (speed difference) between the speed instructed by the
speed instruction (instructed speed) and an actual speed of the Y-axis direction tilt motor 135a,
10 which is calculated by the difference calculation unit 1135-5.
[0069] Further, the speed control unit 1135-1 calculates the first control amount for
controlling the power supply unit 1135-4 on the basis of the received speed difference. In
this case, the speed control unit 1135-1 calculates the first control amount so as to eliminate
the received speed difference. In other words, the speed control unit 1135-1 calculates the
15 first control amount such that the actual motor speed follows the instructed speed.
As the speed control unit 1135-1, it is possible to use a control device that calculates
a control amount such as to eliminate the speed difference on the basis of a control theory, for
example. As this control device, there is a control device using a proportional integral
differential (PID) control theory, for example. In this embodiment, a control device using a
20 proportional integral (PI) control theory is used as the speed control unit 1135-1.
When the speed control unit 1135-1 is the control device using the PI control theory,
the first control amount is expressed as Kpv×Δv+Kiv×Int(Δv), where Δv represents the speed
38
difference, Int(Δv) represents an integrated value over time of the speed difference Δv, and
Kpv and Kiv are constants called control gains.
[0070] The position control unit 1135-2 is connected to the first difference calculation unit
1133 in a manner capable of transmitting and receiving signals. Accordingly, the position
control unit 1135-2 receives the corrected position difference output from the positi5 on
difference eliminating unit 1133. Further, position control unit 1135-2 calculates the second
control amount for controlling the power supply unit 1135-4 so as to eliminate the corrected
position difference output from the position difference eliminating unit 1133.
As the position control unit 1135-2, similarly to the speed control unit 1135-1, a
10 control device that performs control based on a control theory can be used. In this
embodiment, a control device using the PI control theory is used as the position control unit
1135-2.
In this case, the second control amount is expressed as Kpp×Δθ+Kip×Int(Δθ), where
Δθ represents the position difference, Int(Δθ) represents an integrated value over time of the
15 position difference Δθ, and Kpp and Kip are constants called control gains.
[0071] The speed calculation unit 1135-3 is connected to the first rotation information
detection sensor 135a-1 in a manner capable of transmitting and receiving signals. In this
way, the speed calculation unit 1135-3 calculates the rotation speed of the Y-axis direction tilt
motor 135a from the pulse signal output from the first rotation information detection sensor
20 135a-1. The rotation speed of the Y-axis direction tilt motor 135a can be calculated from the
number of pulses per unit time in the pulse signal, for example.
[0072] The power supply unit 1135-4 is connected to the speed control unit 1135-1 via the
39
combining unit 1135-6. In addition, the power supply unit 1135-4 is connected to the
position control unit 1135-2 via the combining unit 1135-6 and the switching unit 1135-7.
In this way, only the first control amount output from the speed control unit 1135-1
is input to the power supply unit 1135-4, or the first control amount and the second control
amount output from the position control unit 1135-2 are combined by the combining 5 unit
1135-6 and input to the power supply unit 1135-4.
[0073] When only the first control amount is input to the power supply unit 1135-4, the
power supply unit 1135-4 outputs the feedback current on the basis of only the first control
amount such that the speed (rotation speed) of the Y-axis direction tilt motor 135a follows the
10 instructed speed. In this way, the motor drive unit 1135 can drive the Y-axis direction tilt
motor 135a so that the rotation speed of the motor follows the instructed speed.
[0074] On the other hand, when the first control amount and the second control amount are
combined by the combining unit 1135-6 and input to the power supply unit 1135-4, the power
supply unit 1135-4 outputs the feedback current such that the rotation speed of the motor
15 follows the instructed speed and that the tilt angle of the training rod 3 follows the instructed
tilt angle. In this way, the motor drive unit 1135 can drive the Y-axis direction tilt motor
135a not only so that the rotation speed of the motor follows the instructed speed but also so
that the tilt angle of the training rod 3 follows the instructed tilt angle.
[0075] Further, in this embodiment, the power supply unit 1135-4 outputs the current
20 (feedback current) controlled based on the first control amount and/or second control amount.
However, output from the power supply unit 1135-4 is not limited to the feedback current.
For instance, the power supply unit 1135-4 may output a voltage whose voltage value and/or
40
duty ratio are controlled on the basis of the first control amount and/or second control
amount.
[0076] In addition, the power supply unit 1135-4 may be connected to the determination
unit 1134. Further, the power supply unit 1135-4 may control the feedback current or
voltage output from the power supply unit 1135-4 on the basis of true or false of the fir5 st
condition described above.
For instance, it is possible not to set a limit to the current value or the voltage value
output from the power supply unit 1135-4 if the first condition is "true", while to set an upper
limit to the current value or the voltage value output that can be output from the power supply
10 unit 1135-4 if the first condition is "false".
In this way, if the position difference change amount generated in the second time
period T2 is the first threshold φ1 or lower (if the first condition is "true"), the Y-axis direction
tilt motor 135a can be controlled so that the position difference is accumulated and
maintained.
15 On the other hand, if the position difference change amount generated in the second
time period T2 is higher than the first threshold φ1 (if the first condition is "false"), the
feedback current or voltage value input to the Y-axis direction tilt motor 135a can be limited.
As a result, when the determination unit 1134 determines an error, the torque output from the
Y-axis direction tilt motor 135a can be limited.
20 [0077] The difference calculation unit 1135-5 has two inputs (an input denoted by "+" and
an input denoted by "-"). The input denoted by "+" of the difference calculation unit 1135-5
is connected to the instruction generation unit 111 in a manner capable of transmitting and
41
receiving signals. In this way, the speed instruction is input to the input denoted by "+" of
the difference calculation unit 1135-5.
In addition, the input denoted by "-" of the difference calculation unit 1135-5 is
connected to an output of the speed calculation unit 1135-3 in a manner capable of
transmitting and receiving signals. In this way, the rotation speed of the Y-axis direction ti5 lt
motor 135a is input to the input denoted by "-" of the difference calculation unit 1135-5.
Thus, the difference calculation unit 1135-5 calculates the difference between the instructed
speed instructed by the speed instruction and the rotation speed of the Y-axis direction tilt
motor 135a, namely the speed difference.
10 [0078] The combining unit 1135-6 combines the first control amount output from the speed
control unit 1135-1 and the second control amount output from the position control unit
1135-2 (combined control amount) and outputs the result to the power supply unit 1135-4.
Here, the combined control amount is a control amount obtained by adding the first control
amount and the second control amount after appropriate weighting. By appropriately
15 adjusting the weighting on the first control amount and the weighting on the second control
amount, it is possible to adjust whether to put importance on the control so that the rotation
speed of the Y-axis direction tilt motor 135a follows the instructed speed (speed control) or
on the control so that the tilt angle of the training rod 3 follows the instructed tilt angle
(position control).
20 [0079] The switching unit 1135-7 is connected to the output of the position control unit
1135-2 and one of inputs of the combining unit 1135-6. In addition, the switching unit
1135-7 is connected to the instruction generation unit 111 for generating the position
42
instruction and the first rotation information detection sensor 135a-1 in a manner capable of
transmitting and receiving signals. In this way, the switching unit 1135-7 can determine
whether or not the number of pulses output from the first rotation information detection
sensor 135a-1 (namely, the tilt angle of the training rod 3) has become a value corresponding
to the deceleration start position instructed by the speed instruction and/or positi5 on
instruction. Further, when the tilt angle of the training rod 3 has become the value
corresponding to the deceleration start position instructed by the speed instruction, the
switching unit 1135-7 can connect the output of the position control unit 1135-2 to the
combining unit 1135-6 in a manner capable of transmitting and receiving signals. In other
10 words, when the amount of rotation of the Y-axis direction tilt motor 135a has becomes the
value corresponding to the deceleration start position instructed by the speed instruction, the
switching unit 1135-7 enables the combining unit 1135-6 to receive the second control
amount that is the output of the position control unit 1135-2.
In this way, only when the speed instruction is the deceleration instruction, the
15 switching unit 1135-7 can reflect the second control amount output from the position control
unit 1135-2 on the control of the Y-axis direction tilt motor 135a. As a result, the training
rod 3 can reach the target tilt angle with a difference as small as possible.
[0080] In addition, the switching unit 1135-7 is connected to the position difference
eliminating unit 1133 in a manner capable of transmitting and receiving signals. For this
20 reason, when the position difference eliminating unit 1133 resets the accumulated and
maintained position difference, the switching unit 1135-7 can connect the output of the
position control unit 1135-2 to the combining unit 1135-6 in a manner capable of transmitting
43
and receiving signals. In this way, when the position difference eliminating unit 1133
physically resets the accumulated and maintained position difference, it is possible to reflect
the second control amount output from the position control unit 1135-2 on calculation of the
feedback current value. As a result, the Y-axis direction tilt motor 135a can be controlled so
that the tilt angle of the training rod 3 follows the instructed tilt angle. Further, 5 the
difference (the position difference) between the actual tilt angle of the training rod 3 and the
instructed angle can be physically reset.
[0081] (5) Operation of training apparatus
I. Basic operation of training apparatus
10 Next, an operation of the training apparatus 100 is described. First, a basic
operation of the training apparatus 100 is described with reference to Fig. 9. Fig. 9 is a
flowchart illustrating a basic operation of the training apparatus 100. Further, in the
following description, an operation of the training apparatus 100 when the training mode is
set to the guided mode is exemplified for describing the operation of the training apparatus
15 100. In addition, an operation in which the Y-axis direction tilt motor 135a is controlled by
the motor control unit 113a is exemplified for describing the operation of the training
apparatus 100. It is because that the control is performed also when the X-axis direction tilt
motor 135b and the expansion/contraction motor 359 are controlled by the motor control
units 113b and the 113c, respectively.
20 First, the user makes various initial settings of the training apparatus 100 by using
the training instruction unit 5 and the like (Step S1). In this case, the user of the training
apparatus 100 sets the training mode to the guided mode by using the training instruction unit
44
5. Further, the user of the training apparatus 100 sets the training program of the limb of the
patient in the guided mode by using the training instruction unit 5.
[0082] Next, the training instruction unit 5 generates the training rod operation instruction
on the basis of the set training program. After that, the training instruction unit 5 transmits
the training rod operation instruction (upper level instruction) to the instruction generati5 on
unit 111 of the control unit 11 (Step S2).
The instruction generation unit 111, which has received the training rod operation
instruction, generates the speed instruction and the position instruction on the basis of the
target position information, the target speed information, and the acceleration rate
10 information included in the training rod operation instruction (Step S3).
[0083] After the instruction generation unit 111 generates the speed instruction and/or
position instruction, the motor control unit 113a controls the Y-axis direction tilt motor 135a
on the basis of the speed instruction and/or the position instruction (Step S4). Details of the
drive of the Y-axis direction tilt motor 135a by the motor control unit 113a in this
15 embodiment will be described later.
[0084] After the motor control unit 113a starts the drive of the Y-axis direction tilt motor
135a, the determination unit 1134 first determines whether or not the position difference
change amount generated in the second time period T2 is the first threshold φ1 or lower (Step
S5).
20 If the position difference change amount generated in the second time period T2 is
the first threshold φ1 or lower ("Yes" in Step S5), the process proceeds to Step S7. On the
other hand, if the position difference change amount generated in the second time period T2 is
45
higher than the first threshold φ1 ("No" in Step S5), the process proceeds to Step S6.
A method of determining the position difference change amount in Step S5 will be
described in detail.
[0085] If the position difference change amount generated in the second time period T2 is
higher than the first threshold φ1 ("No" in Step S5), the determination unit 1134 determine5 s
that an error has occurred (Step S6). In this case, the determination unit 1134 instructs the
training instruction unit 5 to provide visual or auditory information and the like to the user
(the patient and the like) as necessary. In addition, the determination unit 1134 instructs the
motor control unit 113a to perform an appropriate error process considering safety. For
10 instance, the determination unit 1134 instructs the motor drive unit 1135 to stop rotation of
the Y-axis direction tilt motor 135a.
Alternatively, the determination unit 1134 may instruct the motor drive unit 1135 to
perform control of limiting an upper limit of the torque that can be output from the Y-axis
direction tilt motor 135a. In this case, the motor drive unit 1135 limits the feedback current
15 or voltage input to the Y-axis direction tilt motor 135a. In this way, if the position difference
change amount generated in the second time period T2 is higher than the first threshold φ1,
i.e., if the position difference change amount per unit time is excessive, the torque of the
Y-axis direction tilt motor 135a is limited. As a result, the training rod 3 is prevented from
applying an excessive load on the limb of the patient.
20 After the error process is performed, the process proceeds to Step S9.
[0086] If the position difference change amount generated in the second time period T2 is
the first threshold φ1 or lower ("Yes" in Step S5), the position difference eliminating unit
46
1133 monitors whether or not it is a timing for performing position difference correction
(Step S7). In this embodiment, the position difference eliminating unit 1133 monitors (i)
whether or not the determination unit 1134 determines that the position difference change
amount generated in the third time period T3 is the second threshold φ2 or lower, (ii) whether
or not the operation of the training rod 3 (the Y-axis direction tilt motor 135a) has stoppe5 d,
and (iii) whether or not the actual tilt angle of the training rod 3 has reached the deceleration
start position (described later). A specific method of monitoring the three timings by the
position difference eliminating unit 1133 will be described later.
If the position difference eliminating unit 1133 determines that it is not the timing
10 for performing the position difference correction ("No" in Step S7), the process proceeds to
Step S9.
On the other hand, if the position difference eliminating unit 1133 determines that it
is the timing for performing the position difference correction ("Yes" in Step S7), the process
proceeds to Step S8.
15 [0087] If the position difference eliminating unit 1133 determines that it is the timing for
performing the position difference correction ("Yes" in Step S7), the position difference
eliminating unit 1133 resets the accumulated and maintained position difference (Step S8).
The position difference eliminating unit 1133 resets the position difference by (i) a method of
physically resetting the position difference, and/or (ii) a method of setting the position
20 difference value as the parameter handled by the control unit 11 to zero. Methods (i) and (ii)
of resetting the position difference will be described later in detail.
[0088] After the error process in Step S6, after resetting the position difference in Step S8,
47
or if the position difference eliminating unit 1133 determines that it is not the timing for
performing the position difference correction in Step S7 ("No" in Step S7), the motor control
unit 113a determines whether or not the training rod 3 has reached the target tilt angle to be
finally reached by the training rod 3 (Step S9). If the tilt angle of the training rod 3 is the
target tilt angle ("Yes" in Step S9), the control of the Y-axis direction tilt motor 135a by 5 the
motor control unit 113a is finished.
Further, if it is determined in Step S9 that the tilt angle of the training rod 3 is the
target tilt angle, the motor control unit 113a instructs the training instruction unit 5 to inform
the user such as the patient that the tilt angle of the training rod 3 has reached the target tilt
10 angle, using visual or auditory information. In this way, the patient can maintain motivation
to continue the training.
[0089] On the other hand, if the tilt angle of the training rod 3 has not reached the target tilt
angle ("No" in Step S9), the process returns to Step S5.
[0090] Further, whether or not the training rod 3 has reached the target tilt angle may be
15 determined on the basis of the number of pulses output from the first rotation information
detection sensor 135a-1, or on the basis of whether or not all speed instructions and/or
position instructions have been performed.
[0091] II. Motor control method
Next, the method of controlling the motor in Step S4 of Fig. 9 in this embodiment is
20 described with reference to Fig. 10. Fig. 10 is a flowchart illustrating the method of
controlling the motor.
[0092] When starting the drive of the Y-axis direction tilt motor 135a, the switching unit
48
1135-7 first calculates the actual tilt angle of the training rod 3 from the number of pulses
output from the first rotation information detection sensor 135a-1. Further, it is checked
whether or not the calculated tilt angle of the training rod 3 is the tilt angle at which the
deceleration instruction of the speed instruction should be executed (Step S41). In this way,
because it is determined whether or not the deceleration instruction of the speed instructi5 on
should be executed on the basis of the actual tilt angle of the training rod 3, the deceleration
can be started at an appropriate timing. As a result, the training rod 3 can be accurately
moved to the target tilt angle with a difference as small as possible.
[0093] If the actual tilt angle of the training rod 3 has not reached the tilt angle at which the
10 deceleration instruction should be executed ("No" in Step S41), the process proceeds to Step
S42. On the other hand, if the actual tilt angle of the training rod 3 has reached the tilt angle
at which the deceleration instruction should be executed ("Yes" in Step S41), the process
proceeds to Step S43.
[0094] If it is determined in Step S41 that the actual tilt angle of the training rod 3 has not
15 reached the tilt angle at which the deceleration instruction should be executed ("No" in Step
S41), the switching unit 1135-7 disconnect the position control unit 1135-2 from the
combining unit 1135-6 in a manner in which a signal cannot transmitted and received, so that
the second control amount output from the position control unit 1135-2 is not input to the
combining unit 1135-6 (Step S42). In this way, only the first control amount output from
20 the speed control unit 1135-1 is reflected when the power supply unit 1135-4 outputs the
feedback current. As a result, the motor drive unit 1135 controls the Y-axis direction tilt
motor 135a so that the rotation speed of the Y-axis direction tilt motor 135a follows only the
49
instructed speed (speed control).
[0095] If the actual tilt angle of the training rod 3 has not reached the tilt angle at which the
deceleration instruction should be executed, the acceleration instruction or the constant speed
instruction of the speed instruction is executed as illustrated in Figs. 5A, 5B and 6.
Accordingly, when the acceleration instruction or the constant speed instruction of the spee5 d
instruction is executed, the motor drive unit 1135 controls the Y-axis direction tilt motor 135a
so that the rotation speed of the Y-axis direction tilt motor 135a follows only the instructed
speed.
[0096] In addition, when the Y-axis direction tilt motor 135a is controlled so that the
10 rotation speed of the Y-axis direction tilt motor 135a follows only the instructed speed, the
rotation speed of the Y-axis direction tilt motor 135a follows the instructed speed (namely, the
speed difference is canceled), while the position difference is not canceled but is accumulated
and maintained. It is because that when the power supply unit 1135-4 calculates the
feedback current in the speed control, the second control amount is not reflected.
15 [0097] Fig. 11 illustrates a manner in which the speed difference is canceled while the
position difference is accumulated and maintained. As illustrated in Fig. 11, the speed
difference (i) in Fig. 11 is canceled at a time point ta by the speed control. At the time point
ta at which the speed difference (i) is canceled, a position difference ΔθA corresponding to a
time integration of the speed difference (i) (an area of the region illustrated by hatching in the
20 graph) is generated. In this case, because the position control unit 1135-2 is disconnected
from the combining unit 1135-6, the second control amount is not reflected when the
feedback current is calculated. As a result, the position difference ΔθA is not canceled but is
50
maintained. In addition, the speed difference (ii) that is secondly generated is canceled at a
time point tb by the speed control. Further, at the time point tb at which the speed difference
(ii) is canceled, a position difference corresponding to a time integration of the speed
difference (ii) (an area of the region illustrated by crosshatching in the graph) is generated.
Here, because the position difference ΔθA is not canceled but is maintained, at the time poin5 t
tb at which the speed difference (ii) is canceled, the position difference generated by the speed
difference (ii) and the position difference ΔθA generated by the speed difference (i) are
accumulated so that a position difference ΔθB is generated. Further, if the speed difference
is not generated after the time point tb, the position difference ΔθB is not changed and is
10 maintained. On the other hand, if the speed difference is generated after the time point tb,
the position difference generated due to occurrence of the speed difference is accumulated to
ΔθB.
[0098] In the training apparatus 100, it is preferred for the patient to continue the training
even if the position difference is generated in some amount as long as the movement of the
15 limb of the patient can follow the movement of the training rod 3 indicated by the training
rod operation instruction in a certain degree. Accordingly, in this embodiment, when the
acceleration instruction and/or the constant speed instruction of the speed instruction are
executed, the Y-axis direction tilt motor 135a is controlled only by the speed control. In this
way, the Y-axis direction tilt motor 135a can be controlled so as to follow the speed
20 instruction without canceling the position difference. As a result, even if there is the
position difference in some amount, the moving speed of the training rod 3 can follow the
moving speed indicated in the training rod operation instruction while the patient can
51
continue the training of the limb.
[0099] On the other hand, if it is determined that the actual tilt angle of the training rod 3 is
the tilt angle at which the deceleration instruction should be executed ("Yes" in Step S41), a
switching unit 1135-8 connects the position control unit 1135-2 to the combining unit 1135-6
in a manner capable of transmitting and receiving signals (Step S43). In other words, 5 ds, the
second control amount output from the position control unit 1135-2 can be input to the
combining unit 1135-6. In this way, when the deceleration instruction is executed, not only
the first control amount but also the second control amount is reflected when the power
supply unit 1135-4 outputs the feedback current. In this way, when the deceleration
10 instruction is executed, the actual tilt angle of the training rod 3 follows the instructed tilt
angle, too. Accordingly, the training rod 3 can accurately reach the target tilt angle.
[0100] When the motor control unit 113a executes Steps S41 to S43 described above, the
motor control unit 113a can control the Y-axis direction tilt motor 135a to follow only the
speed instruction when the acceleration instruction and/or the constant speed instruction of
15 the speed instruction is executed. Further, when the deceleration instruction is executed, the
Y-axis direction tilt motor 135a can be controlled to follow the speed instruction and the
position instruction.
[0101] Note that the motor control in Step S4 described above is executed until the training
rod 3 reaches the target tilt angle, or until the operation of the training rod 3 is stopped due to
20 occurrence of an error or user's instruction.
[0102] III. Method of determining whether or not position difference change amount is
within allowable range
52
Next, a method of determining whether or not the position difference change amount
is within an allowable range in Step S5 of the flowchart illustrated in Fig. 9 is described with
reference to Fig. 12. Fig. 12 is a flowchart illustrating the method of determining whether
or not the position difference change amount is within an allowable range.
When the determination whether or not the position difference change amount 5 is
within an allowable range is started, the determination unit 1134 first determines whether or
not an elapsed time t from start of the drive of the Y-axis direction tilt motor 135a is an
multiple of the second time period T2 and an integer (n) (Step S51). If the elapsed time t is
not an integral multiple of the second time period T2 ("No" in Step S51), the determination
10 unit 1134 does not determine whether or not the position difference change amount is within
the allowable range, and finishes the determination whether or not the position difference
change amount is within the allowable range. Then, the process proceeds to Step S7.
[0103] On the other hand, if the elapsed time t is an integral multiple of the second time
period T2 ("Yes" in Step S51), the determination unit 1134 obtains the accumulated and
15 maintained position difference from the position difference calculation unit 1132 (Step S52).
Further, the determination unit 1134 regards the obtained position difference as an
accumulated and maintained position difference Δθn at an elapsed time t=nT2 and stores the
same in the storage device of the motor control unit 113a or the like.
[0104] Note that the position difference calculation unit 1132 calculates the position
20 difference at an interval of the first time period T1. It is because that the position difference
calculation unit 1132 is connected to the motor drive unit 1135 via the position difference
eliminating unit 1133, and the motor drive unit 1135 controls the Y-axis direction tilt motor
53
135a on the basis of the position difference calculated by the position difference calculation
unit 1132 (or corrected by the position difference eliminating unit 1133).
On the other hand, the second time period T2 in which the determination unit 1134
obtains the position difference is a time interval for determining a position difference change
amount per unit time. Accordingly, the second time period T2 may be a time interva5 l
sufficiently longer than the first time period T1. Because the second time period T2 is a time
interval sufficiently longer than the first time period T1, a calculation load in the motor
control unit 113a can be reduced.
[0105] Next, the determination unit 1134 determines whether or not the position difference
10 generated per second time period T2 is the first threshold φ1 or lower (Step S53).
Specifically, the determination is performed as follows.
First, the determination unit 1134 reads out a position difference Δθn-1 calculated last
time, namely the position difference accumulated and maintained at the elapsed time
t=(n-1)T2 from the storage device of the motor control unit 113a or the like. Further, the
15 determination unit 1134 calculates a difference Δθn-Δθn-1 between the position difference Δθn
at the elapsed time t=nT2 and the position difference Δθn-1 at the elapsed time t=(n-1)T2. In
this way, the position difference change amount generated per second time period T2 (namely,
per unit time) is calculated at the elapsed time t=nT2. After that, the determination unit 1134
determines whether or not Δθn-Δθn-1 is the first threshold φ1 or lower.
20 If Δθn-Δθn-1 is the first threshold φ1 or lower ("Yes" in Step S53), it is determined
that the position difference change amount is within the allowable range (Step S54), and
finishes determination whether or not the position difference change amount is within the
54
allowable range. On the other hand, if Δθn-Δθn-1 is higher than first threshold φ1 ("No" in
Step S53), it is determined that the position difference change amount is not within the
allowable range (Step S55), and finishes the determination whether or not the position
difference change amount is within the allowable range.
[0106] In this way, when the difference between the position difference obtained at a certa5 in
elapsed time and the position difference obtained the second time period T2 before the certain
elapsed time is calculated, the position difference change amount generated per the second
time period T2 can be calculated. Further, by determining whether or not the position
difference change amount per the second time period T2 is the first threshold φ1 or lower, the
10 determination unit 1134 can determine whether the position difference generated per unit
time (the position difference change amount per unit time) is a slow position difference
change or a rapid position difference change.
[0107] IV. Method of determining timing for performing correction (reset) of position
difference
15 Next, a method of determining the timing for performing the correction (reset) of the
position difference in Step S7 will be described with reference to Figs. 13A to 13C. The
timing of the correction (reset) of the position difference in Step S7 is (i) whether or not the
determination unit 1134 determines that the position difference change amount generated in
the third time period T3 is the second threshold φ2 or lower, (ii) whether or not operation of
20 the training rod 3 (the Y-axis direction tilt motor 135a) has stopped, or (iii) whether or not the
actual tilt angle of the training rod 3 has reached the deceleration start position. Each
method of determining the timing is explained below. Fig. 13A is a flowchart illustrating
55
the method of determining whether or not the position difference change amount generated in
the third time period T3 is the second threshold φ2 or lower. Fig. 13B is a flowchart
illustrating a method of determining whether or not the operation of the training rod 3 (or the
Y-axis direction tilt motor 135a) is stopped. Fig. 13C is a determining illustrating a method
of determining whether or not the tilt angle of the training rod 3 has reached the decelerati5 on
start position.
[0108] (i) Method of determining whether or not position difference change amount
generated in third time period T3 is second threshold φ2 or lower
The method of determining whether or not the position difference change amount
10 generated in the third time period T3 is the second threshold φ2 or lower is described below
with reference to Fig. 13A.
First, the determination unit 1134 determines whether or not the elapsed time t from
start of the drive of the Y-axis direction tilt motor 135a is a multiple of the third time period
T3 and an integer (n) (Step S51). If the elapsed time t is not an integral multiple of the third
15 time period T3 ("No" in Step S711), the determination unit 1134 finishes the determination.
Then, the process proceeds to Step S9.
[0109] On the other hand, if the elapsed time t is an integral multiple of the third time
period T3 ("Yes" in Step S711), the determination unit 1134 obtains the accumulated and
maintained position difference from the position difference calculation unit 1132 (Step S712).
20 Further, the determination unit 1134 regards the obtained position difference as the position
difference ΔΘn accumulated and maintained at the elapsed time t=nT3, and stores the same in
the storage device of the motor control unit 113a or the like.
56
[0110] Next, the determination unit 1134 determines whether or not the position difference
change amount generated per the third time period T3 is the second threshold φ2 or lower
(Step S713). Specifically, the determination is performed as follows. First, the
determination unit 1134 reads out the position difference ΔΘn-1 calculated last time, namely
the position difference accumulated and maintained at the elapsed time t=(n-1)T3 from 5 om the
storage device of the motor control unit 113a or the like. Further, the determination unit
1134 calculates the difference ΔΘn-ΔΘn-1 between the position difference ΔΘn at the elapsed
time t=nT3 and the position difference ΔΘn-1 at the elapsed time t=(n-1)T3. In this way, the
position difference change amount generated per the third time period T3 (namely, per unit
10 time) is calculated at the elapsed time t=nT3. After that, the determination unit 1134
determines whether or not ΔΘn-ΔΘn-1 is the second threshold φ2 or lower.
If ΔΘn-ΔΘn-1 is the second threshold φ2 or lower ("Yes" in Step S713), the
determination unit 1134 determines that the position difference change amount per the third
time period T3 is the second threshold φ2 or lower, i.e., that it is the timing for performing the
15 correction (reset) of the position difference (Step S714), and finishes the determination
whether or not the position difference change amount per the third time period T3 is the
second threshold φ2 or lower. On the other hand, if ΔΘn-ΔΘn-1 is higher than the second
threshold φ2 ("No" in Step S53), the determination unit 1134 determines that the position
difference change amount per the third time period T3 is not the second threshold φ2 or lower,
20 i.e., that it is not the timing for performing the correction (reset) of the position difference
(Step S715), and finishes the determination whether or not the position difference change
amount per the third time period T3 is the second threshold φ2 or lower.
57
[0111] (ii) Method of determining whether or not operation of training rod (or motor) is
stopped
Next, a method of determining whether or not the operation of the training rod 3 (or
the Y-axis direction tilt motor 135a) is stopped is described with reference to Fig. 13B.
First, the position difference eliminating unit 1133 determines whether or 5 not the
operation of the training rod 3 is stopped (Step S721). Whether or not the operation of the
training rod 3 is stopped is determined on the basis of (i) whether or not the tilt angle of the
training rod 3 is not substantially changed (when the patient has instructed to stop), (ii)
whether or not the training rod 3 has reached the target tilt angle instructed by the position
10 instruction, and/or, (iii) whether or not the speed instruction is all executed.
[0112] If the determination is performed on the basis of the tilt angle of the training rod 3 as
(i) and (ii) described above, the position difference eliminating unit 1133 subtracts the
position difference calculated by the position difference calculation unit 1132 from the
instructed tilt angle instructed by the position instruction so as to calculate the actual tilt angle
15 of the training rod 3. Other than that, the position difference eliminating unit 1133 may
obtain the tilt angle of the training rod 3 directly from the tilt angle calculation unit 1131.
Whether or not the tilt angle of the training rod 3 is not changed as (i) described
above can be determined on the basis of whether or not the actual tilt angle of the training rod
3 calculated by the position difference eliminating unit 1133 has changed in a predetermined
20 time period.
Whether or not the training rod 3 has reached the target tilt angle instructed by the
position instruction as (ii) described above can be determined on the basis of whether or not
58
the actual tilt angle of the training rod 3 calculated by the position difference eliminating unit
1133 is the same as the target tilt angle.
[0113] Whether or not the speed instruction is all executed as (iii) described above can be
determined, for example, on the basis of whether or not the elapsed time t from the start of
the drive of the Y-axis direction tilt motor 135a becomes an elapsed time t5 (in the case of 5 the
speed instruction of Fig. 5A) or the elapsed time t3 (in the case of the speed instruction of Fig.
5B) indicated in the speed instruction illustrated in Figs. 5A and 5B.
[0114] If the position difference eliminating unit 1133 determines that the operation of the
training rod 3 is stopped ("Yes" in Step S721), it is determined to be the timing to correct
10 (reset) the accumulated and maintained position difference (Step S722), and the
determination is finished. On the other hand, if the position difference eliminating unit 1133
determines that the operation of the training rod 3 is not stopped ("No" in Step S721), it is
determined not to be the timing to correct (reset) the accumulated and maintained position
difference (Step S723), and the determination is finished.
15 [0115] Other than that, the position difference eliminating unit 1133 may directly monitor
the rotation speed of the Y-axis direction tilt motor 135a calculated by the speed calculation
unit 1135-3, so as to determine that the operation of the training rod 3 is stopped when the
rotation speed becomes zero (or a predetermined value close to zero).
[0116] (iii) Method of determining whether or not tilt angle of training rod has reached
20 deceleration start position
Next, a method of determining whether or not the tilt angle of the training rod 3 has
reached the deceleration start position is described with reference to Fig. 13C.
59
First, the position difference eliminating unit 1133 determines whether or not the tilt
angle of the training rod 3 has reached the deceleration start position of the Y-axis direction
tilt motor 135a (Step S731). Whether or not the tilt angle of the training rod 3 has reached
the deceleration start position is determined on the basis of whether or not the tilt angle of the
training rod 3 is the same as an instructed tilt angle θd at the elapsed time t2 in the positi5 on
instruction illustrated in Fig. 6. Here, whether or not to be the deceleration start position of
the Y-axis direction tilt motor 135a is not determined on the basis of the elapsed time t from
the start of the drive of the Y-axis direction tilt motor 135a (namely, on the basis of whether
or not the elapsed time t is equal to t2).
10 [0117] If it is determined whether or not to be the deceleration start position of the Y-axis
direction tilt motor 135a on the basis of whether or not the elapsed time t from the start of the
drive of the Y-axis direction tilt motor 135a is equal to t2, unintentional reset of the position
difference may be performed when the acceleration instruction or the constant speed
instruction of the speed instruction is executed.
15 For instance, if a position difference occurs when the acceleration instruction or the
constant speed instruction is executed, the actual tilt angle of the training rod 3 has not
reached the deceleration start position θd instructed by the speed instruction (position
instruction) at the time point when the elapsed time t is t2. In this case, even if the elapsed
time t is t2, the acceleration instruction or the constant speed instruction is executed. In this
20 way, if the position difference is simply reset at the elapsed time t2, the position difference is
reset before the actual tilt angle of the training rod 3 reaches the deceleration start position,
which is unintentional reset of the position difference.
60
[0118] Accordingly, the deceleration instruction is executed after the actual tilt angle of the
training rod 3 reaches the deceleration start position θd instructed by the speed instruction
(position instruction), and hence the unintentional stop of the training rod 3 can be prevented.
In addition, the timing to reset the position difference is determined on the basis of
whether or not the actual tilt angle of the training rod 3 is equal to the deceleration 5 on start
position θd, and hence it is possible to avoid the unintentional reset of the position difference
when the acceleration instruction or the constant speed instruction is executed.
[0119] If the position difference eliminating unit 1133 determines that the actual tilt angle
of the training rod 3 is equal to the deceleration start position θd ("Yes" in Step S731), it is
10 determine to be the timing to correct (reset) the accumulated and maintained position
difference (Step S732), and the determination is finished. On the other hand, if the position
difference eliminating unit 1133 determines that the tilt angle of the training rod 3 is not equal
to the deceleration start position θd ("No" in Step S731), it is determined not to be the timing
to correct (reset) the position difference (Step S733), and the determination is finished.
15 [0120] V. Method of position difference correction
Next, a method of correcting (resetting) the position difference in Step S8 of the
flowchart illustrated in Fig. 9 is described with reference to Figs. 14A to 15B. Fig. 14A is a
flowchart illustrating a method of physically resetting the position difference. Fig. 14B is a
flowchart illustrating an example of a method of resetting the position difference by setting
20 the position difference value as a parameter to zero. Fig. 15A is a diagram schematically
illustrating a method of resetting the position difference by physically resetting the position
difference. Fig. 15B is a diagram schematically illustrating a method of resetting the
61
position difference by setting the position difference value as a parameter to zero.
In Step S8, the position difference eliminating unit 1133 resets the position
difference by (i) a method of physically resetting the position difference, and/or (ii) a method
of setting the position difference value as a parameter handled by the control unit 11 is set to
zero. Hereinafter, each method of resetting the position difference is describe5 d.
[0121] (i) Method of physically resetting position difference
First, a method of physically resetting the position difference is described with
reference to Figs. 14A and 15A. Here, "physically" resetting the position difference means
to make the actual tilt angle of the training rod 3 equal to the instructed tilt angle of the
10 position instruction.
First, at the timing to perform the correction (reset) of the position difference, the
position difference eliminating unit 1133 instructs the switching unit 1135-7 of the motor
drive unit 1135 to connect the position control unit 1135-2 to the combining unit 1135-6 in a
manner capable of transmitting and receiving signals (Step S811). Further, the switching
15 unit 1135-7 connects the position control unit 1135-2 to the combining unit 1135-6 in a
manner capable of transmitting and receiving signals. In this way, the second control
amount output from the position control unit 1135-2 can be input to the combining unit
1135-6. Accordingly, the power supply unit 1135-4 can reflect the second control amount
when the feedback current or voltage value that is input to the Y-axis direction tilt motor 135a
20 is calculated. As a result, the motor drive unit 1135 can control the Y-axis direction tilt
motor 135a so that the tilt angle of the training rod 3 becomes equal to the instructed tilt angle
instructed by the position instruction.
62
[0122] Next, the position difference eliminating unit 1133 determines whether or not a
correction condition is satisfied (Step S812). Here, the correction condition is a condition
for determining whether or not to reflect the second control amount on the control of the
Y-axis direction tilt motor 135a. The correction condition may be, for example, whether or
not the actual tilt angle of the training rod 3 is equal to the instructed tilt angle (or 5 the position
difference is within a predetermined range). When whether or not the actual tilt angle of the
training rod 3 is equal to the instructed tilt angle (or the position difference is within a
predetermined range) is used as the correction condition, the actual tilt angle of the training
rod 3 can be equal to the instructed tilt angle (or can be within a predetermined range).
10 Other than that, the correction condition may be whether or not a period while the
position control unit 1135-2 is connected to the combining unit 1135-6 in Step S811 is a
predetermined time period or longer. When whether or not the period while the position
control unit 1135-2 is connected to the combining unit 1135-6 is a predetermined time period
or longer is used as the correction condition, the actual tilt angle of the training rod 3 can be
15 close to the instructed tilt angle, and at the same time, an excessive increase of the rotation
speed of the Y-axis direction tilt motor 135a, which is caused by the second control amount
reflected too long on the control of the Y-axis direction tilt motor 135a, can be prevented.
[0123] When determining that the correction condition is satisfied ("Yes" in Step S812), the
position difference eliminating unit 1133 instructs the switching unit 1135-7 to disconnect
20 between the position control unit 1135-2 and the combining unit 1135-6 (Step S813). As a
result, the second control amount is not input to the combining unit 1135-6. Further, the
reset of the position difference is finished.
63
On the other hand, when determining that the correction condition is not satisfied
("No" in Step S812), the position difference eliminating unit 1133 instructs the switching unit
1135-7 to maintain the connection between the position control unit 1135-2 and the
combining unit 1135-6. In this way, the reset determination of the accumulated and
maintained position difference is continued until the correction condition is satisfie5 d.
[0124] The operation of the method of physically resetting the position difference is further
described with reference to Fig. 15A. In Fig. 15A, it is supposed that two speed changes (i)
and (ii) have occurred. In this case, due to these two speed changes, a position difference
Δθ3 is generated at an elapsed time t=3T3, and a position difference Δθ5 is generated at an
10 elapsed time t=5T3.
[0125] In Step S7 described above, a case where the timing for resetting the position
difference is a timing at which the position difference change amount per the third time
period T3 is the second threshold φ2 or lower is exemplified. Then, if the position difference
change amount Δθ3-Δθ2 at the elapsed time 3T3 is the second threshold φ2 or lower, the
15 second control amount from the position control unit 1135-2 is reflected on the feedback
current or voltage input to the Y-axis direction tilt motor 135a by Step S811 described above.
As a result, after the elapsed time 3T3, the Y-axis direction tilt motor 135a is controlled so
that the position difference Δθ3 is eliminated. i.e., the actual tilt angle of the training rod 3
becomes equal to the instructed tilt angle. In this case, the rotation speed of the Y-axis
20 direction tilt motor 135a is temporarily higher than the instructed speed instructed by the
speed instruction (speed change (1)). Due to the temporary speed increase as the speed
change (1), the position difference Δθ3 is canceled before an elapsed time 4T3.
64
[0126] On the other hand, if the position difference change amount Δθ5-Δθ4 at the elapsed
time 5T3 is the second threshold φ2 or lower, and if the correction condition is that the actual
tilt angle of the training rod 3 is equal to the instructed tilt angle (the position difference is
zero), the position difference Δθ5 generated at the elapsed time 5T3 is canceled before an
elapsed time 7T3 due to the speed change (2) generated when the second control amount 5 is
reflected on the input to the Y-axis direction tilt motor 135a. Further, because a position
difference Δθ6 is not zero at an elapsed time 6T3, the operation of resetting the position
difference is continued (namely, the connection state between the position control unit 1135-2
and the combining unit 1135-6 is maintained).
10 [0127] In this way, by continuing the reset determination of the position difference until the
correction condition is satisfied, the actual tilt angle of the training rod 3 can be equal (or
close) to the instructed tilt angle. For this reason, as illustrated in Fig. 15A, an excessive
increase of the accumulated and maintained position difference can be prevented. As a
result, when a slow position difference change has continued for a long period of time, an
15 error is not determined, and hence the patient can continue the training of the limb using the
training apparatus 100.
[0128] Note that it is preferred that a maximum value of the rotation speed of the Y-axis
direction tilt motor 135a in the speed changes (1) and (2) be not too large. For instance, the
weighting value used for combining the first control amount and the second control amount
20 in the combining unit 1135-6 is optimized (for example, the weighting of the second control
amount is decreased), or the control gains Kpp and Kpv for the position control are set to small
values, and hence it is possible to prevent the rotation speed of the Y-axis direction tilt motor
65
135a from being too large during execution of the position control.
In addition, in the speed changes (1) and (2), the maximum value of the rotation
speed of the Y-axis direction tilt motor 135a is suppressed, and hence it is possible to prevent
the load applied on the limb by the training rod 3 from being too large.
[0129] (ii) Method of resetting position difference by setting position difference value as 5 s a
parameter to zero
Next, a method of resetting the position difference by setting the position difference
value as a parameter to zero is described with reference to Figs. 14B and 15B. Here, a
method of resetting the position difference at the elapsed time 3T3 in Fig. 15A is exemplified
10 and described.
First, an actual tilt angle of the training rod 3 at the timing at which the position
difference eliminating unit 1133 resets the accumulated and maintained position difference is
calculated (Step S821). In the position difference eliminating unit 1133, the actual tilt angle
of the training rod 3 at the elapsed time 3T3 is θ3.
15 [0130] Next, the position difference eliminating unit 1133 obtains the time point when the
instructed tilt angle indicated by the position instruction becomes θ3 from the position
instruction (Step S822). It is supposed that the position instruction is expressed by a
function P(t), and then the time point t in the position instruction when the instructed tilt
angle becomes θ3 is 3T3-Δt (namely, P(3T3-Δt)=θ3). Further, the position difference
20 eliminating unit 1133 calculates the difference Δt between the time point when the instructed
tilt angle in the position instruction becomes θ3 and the time point when the tilt angle of the
training rod 3 actually becomes θ3.
66
[0131] Next, the position difference eliminating unit 1133 updates the function P(t) of the
position instruction (Step S823). In Step S823, the function P(t) of the position instruction
is converted from the function P(t) to the function P(t-Δt) at the elapsed time 3T3 so as to be
updated. This means that in Fig. 15B, at the elapsed time 3T3, the function P(t) of the
position instruction (the position instruction illustrated by a dot-dashed line in Fig. 15B) 5 ) is
moved in parallel behind by Δt on the time axis (to the right in Fig. 15B) (to be the position
instruction illustrated by a double dot-dashed line in Fig. 15B). Further, at the elapsed time
3T3, the instructed tilt angle indicated in the position instruction is P(3T3-Δt), namely θ3. As
a result, the difference (the position difference) between the actual tilt angle of the training
10 rod 3 and the instructed tilt angle becomes zero.
Further, as illustrated in Fig. 15B, when setting the position difference as a
parameter to zero so as to reset the position difference, the position difference between the
actual tilt angle of the training rod 3 and the instructed tilt angle indicated in the last position
instruction P(t) is accumulated as it is and is maintained.
15 [0132] In addition, when the function P(t) of the position instruction is updated to P(t-Δt), a
function V(t) of the speed instruction is also updated to V(t-Δt). For instance, as illustrated
in Fig. 15C, when the function P(t) of the position instruction is updated to a function P(t-Δtc)
(a position instruction illustrated by a double dot-dashed line in Fig. 15C) at an elapsed time
mT3 (m is an integer), the updated speed instruction V(t-Δtc) (a speed instruction illustrated
20 by a double dot-dashed line in Fig. 15C) corresponds to a function obtained by moving the
speed instruction V(t) before the update in parallel behind by Δtc on the time axis. In this
way, the reaching time is delayed by Δtc, but the position instruction appropriately
67
corresponds to the speed instruction in a temporal manner. As a result, the motor control
unit 113a can control the Y-axis direction tilt motor 135a so that the training rod 3 can
accurately reach the target tilt angle with a difference as small as possible.
In addition, in the method of resetting the position difference as a parameter to zero,
the motor control unit 113a does not perform the position control for physically canceling 5 the
position difference. For this reason, the tilt angle of the training rod 3 per unit time does not
exceed the instructed speed instructed by the speed instruction. As a result, the training can
be safely continued.
[0133] (6) Effects of this embodiment
10 Hereinafter, effects of this embodiment are described.
The training apparatus 100 (an example of the training apparatus) is a training
apparatus for training an upper limb and/or a lower limb of a patient (an example of the
patient) in accordance with a training program (an example of the training program). The
training apparatus 100 includes the fixed frame 1 (an example of the fixed frame), the
15 training rod 3 (an example of the training rod), the X-axis direction tilt motor 135b (an
example of the motor), the Y-axis direction tilt motor 135a (an example of the motor), the
second rotation information detection sensor 135b-1 (an example of the rotation information
detection sensor), the first rotation information detection sensor 135a-1 (an example of the
rotation information detection sensor), the tilt angle calculation unit 1131 (an example of the
20 tilt angle calculation unit), the position difference calculation unit 1132 (an example of the
position difference calculation unit), the determination unit 1134 (an example of the
determination unit), the motor drive unit 1135 (an example of the motor drive unit), and the
68
position difference eliminating unit 1133 (an example of the position difference eliminating
unit). The fixed frame 1 is placed on or in the vicinity of a floor. The training rod 3 is
supported by the fixed frame 1 in a manner capable of tilting about at least the X-axis or the
Y-axis (an example of the predetermined tilting axis). In addition, the training rod 3 holds
the limb (an example of the limb). The X-axis direction tilt motor 135b and the Y-5 axis
direction tilt motor 135a tilt the training rod 3 about the X-axis and the Y-axis, respectively.
The first rotation information detection sensor 135a-1 and the second rotation information
detection sensor 135b-1 output an amount of rotation of the Y-axis direction tilt motor 135a
and an amount of rotation of the X-axis direction tilt motor 135b, respectively. The tilt
10 angle calculation unit 1131 calculates a tilt angle of the training rod 3 (an example of the tilt
angle) on the basis of the amount of rotation of the X-axis direction tilt motor 135b and the
amount of rotation of the Y-axis direction tilt motor 135a. The position difference
calculation unit 1132 calculates the position difference (an example of the position
difference) at the interval of the first time period T1 (an example of the first time period).
15 The determination unit 1134 obtains the position difference calculated by the position
difference calculation unit 1132 every time when the second time period T2 (an example of
the second time period) elapses. Further, the determination unit 1134 determines whether or
not the position difference change amount generated in the second time period T2 is the first
threshold φ1 (an example of the first threshold) or lower. When the determination unit 1134
20 determines that the position difference change amount generated in the second time period T2
is the first threshold φ1 or lower, the motor drive unit 1135 drives the X-axis direction tilt
motor 135b and the Y-axis direction tilt motor 135a so that the position difference is
69
accumulated and maintained. The position difference eliminating unit 1133 resets the
accumulated and maintained position difference at the preset timing.
[0134] In the training apparatus 100, the determination unit 1134 first obtains the position
difference every time when the unit time (the second time period T2) elapses. Next, the
determination unit 1134 calculates the position difference change amount generated in 5 the
second time period T2. Further, the determination unit 1134 determines whether or not the
position difference change amount generated in the second time period T2 is the first
threshold φ1 or lower.
When the determination unit 1134 determines that the position difference change
10 amount generated in the second time period T2 is the first threshold φ1 or lower, the motor
drive unit 1135 drives one of the X-axis direction tilt motor 135b and the Y-axis direction tilt
motor 135a so that the position difference is accumulated and maintained. Further, the
position difference eliminating unit 1133 resets the accumulated and maintained position
difference at the preset timing while the X-axis direction tilt motor 135b and the Y-axis
15 direction tilt motor 135a are driven.
[0135] In this way, the determination unit 1134 obtains the position difference every time
when the unit time (second time period T2) elapses. In this way, the position difference
change amount generated in the unit time (second time period T2) can be calculated. In
addition, the determination unit 1134 determines whether or not the position difference
20 change amount generated in the unit time (second time period T2) is the first threshold φ1 or
lower. In this way, the determination unit 1134 can appropriately determine the case where
the following status in which the position difference is not zero but is not changed has
70
occurred, or the case where the following status in which the position difference gradually
changes has occurred.
Further, the position difference eliminating unit 1133 resets the accumulated and
maintained position difference at the predetermined timing. In this way, it is avoided that
the determination unit 1134 determines an error when the position difference generated 5 ted in the
state where the position difference is not zero but is not changed, or the position difference
generated in the state where the position difference gradually changes is increased. As a
result, the patient can continue the training of the limb with the training apparatus 100.
[0136] The training rod 3 may be expandable and contractible in the longitudinal direction
10 (an example of the longitudinal axis direction). When the training rod 3 is expandable and
contractible in the longitudinal axis direction, it is possible to carry out the training of an
upper limb or a lower limb (limb) in the longitudinal direction of the training rod 3.
[0137] If the position difference change amount generated in the second time period T2 is
higher than the first threshold φ1, the determination unit 1134 determines an error. In this
15 way, it is possible to predict a potential abnormality in the training apparatus 100, and/or, a
potential obstacle that may affect continuation of the training, so as to appropriately
determine that the limb cannot follow the training program.
[0138] The training apparatus 100 further includes the training instruction unit 5 (an
example of the information providing unit). When the determination unit 1134 determines
20 that an error has occurred, the training instruction unit 5 provides the user with visual or
auditory information.
In this way, it is possible to inform the user of the status of the training apparatus
71
and/or a potential obstacle that may affect continuation of the training.
[0139] When the patient has moved the training rod 3 to reach the target tilt angle (an
example of the passing point preset in the training route set by the training program), the
training instruction unit 5 provides the user with information. In this way, the user can
know that the training rod 3 has been operated just in accordance with the training progra5 m.
In addition, because the user is provided with the visual or auditory information when the
patient has moved the training rod 3 to reach the target tilt angle, the patient can maintain
motivation to continue the training.
[0140] When the determination unit 1134 determines that an error has occurred, the X-axis
10 direction tilt motor 135b, the Y-axis direction tilt motor 135a, and the expansion/contraction
motor 359 (an example of the motor) may be stopped. In this way, when an error has
occurred, i.e., when it is determined that there is a potential obstacle that may affect
continuation of the training, the training apparatus 100 can be safely stopped.
[0141] The determination unit 1134 further obtains the position difference every time when
15 the third time period T3 (an example of the third time period) elapses. Further, the
determination unit 1134 determines whether or not the position difference change amount
generated in the third time period T3 is the second threshold φ2 (an example of the second
threshold) or lower. Further, when the determination unit 1134 determines that the position
difference change amount generated in the third time period T3 is the second threshold φ2 or
20 lower, the position difference eliminating unit 1133 resets the accumulated and maintained
position difference.
In this way, the accumulated and maintained position difference can be reset without
72
always controlling the X-axis direction tilt motor 135b, the Y-axis direction tilt motor 135a,
and/or the expansion/contraction motor 359 (the position control) so that the actual tilt angle
of the training rod 3 follows the tilt angle instructed by the training program (the instructed
tilt angle), and the patient can continue the training.
[0142] The position difference eliminating unit 1133 resets the accumulated and 5 nd maintained
position difference when the operation of the training rod 3 is stopped. In this way, the
position difference generated in the training this time is not carried over to the next training
and after, and hence the patient can continue the training.
[0143] The training apparatus 100 further includes the instruction generation unit 111 (an
10 example of the instruction generation unit). The instruction generation unit 111 generates
the speed instruction (an example of the speed instruction) including at least the acceleration
instruction (an example of the acceleration instruction) for accelerating the X-axis direction
tilt motor 135b, the Y-axis direction tilt motor 135a, and/or the expansion/contraction motor
359 in accordance with the preset training program, and the deceleration instruction (an
15 example of the deceleration instruction) for decelerating the motors. In this case, the motor
drive unit 1135 controls the motor so as to follow only the speed instruction when the
acceleration instruction is executed.
Because the speed instruction including at least the acceleration instruction and the
deceleration instruction is used for driving the motor, the motor can be smoothly operated.
20 As a result, the patient can operate the training rod 3 as intended.
In addition, because the motor drive unit 1135 drives the motor so as to follow only
the speed instruction when the acceleration instruction is executed, the motor control can be
73
performed so that the position difference is accumulated and maintained. As a result, even
if a relatively large motor torque is required and a position difference is apt to occur, for
example, even if the training rod 3 is operated at a large tilt angle, the patient can continue the
training of the limb using the training apparatus 100. Further, because the position
difference is accumulated and maintained, a state of the limb during the training can 5 n be
grasped on the basis of the accumulated and maintained amount of the position difference.
[0144] The speed instruction includes at least the acceleration instruction and the
deceleration instruction, and can further include the constant speed instruction for rotating the
motor at a constant speed. In this case, the motor drive unit 1135 controls the motor so as to
10 further follow only the speed instruction when the constant speed instruction is executed.
Because the speed instruction further includes the constant speed instruction, the
motor can be smoothly operated at a constant speed on the basis of the feedback current from
the motor even if the training rod 3 is operated at a large tilt angle. In addition, because the
motor drive unit 1135 controls the motor so as to follow only the speed instruction when the
15 constant speed instruction is executed, the motor control can be performed so that the
position difference is accumulated and maintained. As a result, even if a relatively large
motor torque is required and a position difference is apt to occur, for example, even if the
training rod 3 is operated at a large tilt angle, the patient can continue the training of the limb
using the training apparatus 100. In addition, when the motor is rotated at a constant speed,
20 the training of the limb can be continued by a constant speed movement. Further, because
the position difference is accumulated and maintained, a state of the limb of the patient
during the training can be grasped on the basis of the accumulated and maintained amount of
74
the position difference.
[0145] The instruction generation unit 111 further generates the position instruction (an
example of the position instruction) for controlling the tilt angle of the training rod 3 in
accordance with the training program. In addition, the motor drive unit 1135 controls the
motor so as to follow the speed instruction and the position instruction when the decelerati5 on
instruction is executed.
In this way, the motor drive unit 1135 can control the motor so that the training rod 3
can reach the target tilt angle instructed by the training program with a difference as small as
possible. As a result, when the position information of the training rod 3 is fed back as the
10 visual information to the patient, for example, this position information can be appropriately
used.
[0146] The position difference eliminating unit 1133 resets the accumulated and maintained
position difference when the deceleration instruction is started. In this way, when the
deceleration instruction is executed, the rotation speed of the motor can be prevented from
15 being excessively increased by the position instruction.
[0147] 2. Other embodiments
Although an embodiment of the present invention is described above, the present
invention is not limited to the embodiment but can be modified variously within the scope of
the spirit of the invention. In particular, a plurality of embodiments and variations described
20 in this specification can be arbitrarily combined as necessary.
(A) Another embodiment concerning motor control
In the first embodiment described above, only when the deceleration instruction of
75
the speed instruction is executed, the Y-axis direction tilt motor 135a (the X-axis direction tilt
motor 135b or the expansion/contraction motor 359) is controlled so that the tilt angle of the
training rod 3 follows the instructed tilt angle instructed by the position instruction (position
control). However, this is not a limitation. Also when the acceleration instruction of the
speed instruction is executed and/or when the constant speed instruction is executed, 5 d, the
Y-axis direction tilt motor 135a (the X-axis direction tilt motor 135b or the
expansion/contraction motor 359) may be controlled by the position control and the speed
control. In this case, the switching unit 1135-8 of the motor drive unit 1135 is not necessary
in particular.
10 [0148] When the acceleration instruction of the speed instruction is executed and/or when
the constant speed instruction is executed, if the Y-axis direction tilt motor 135a (the X-axis
direction tilt motor 135b or the expansion/contraction motor 359) is controlled by the position
control, it is preferred to adjust the control gains Kpp and Kip or to adjust the weighting value
of the second control amount of the combining unit 1135-6 so that the tilt angle speed of the
15 training rod 3 does not become excessively large.
In this way, the tilt angle of the training rod 3 can follow the instructed tilt angle
without excessively increasing the tilt angle speed of the training rod 3.
INDUSTRIAL APPLICABILITY
20 [0149] The present invention can be widely applied to a training apparatus including a
training rod driven by a motor, for carrying out training of a limb of a patient in accordance
with a predetermined training program.
76
REFERENCE SIGNS LIST
[0150]
100 training apparatus
1 fixed frame
11 control 5 ontrol unit
111 instruction generation unit
113a, 113b, 113c motor control unit
1131 tilt angle calculation unit
1132 position difference calculation unit
10 1133 position difference eliminating unit
1134 determination unit
1135 motor drive unit
1135-1 speed control unit
1135-2 position control unit
15 1135-3 speed calculation unit
1135-4 power supply unit
1135-5 difference calculation unit
1135-6 combining unit
1135-7 switching unit
20 13 training rod tilt mechanism
131 X-axis direction tilt member
131a, 131b shaft
77
133 Y-axis direction tilt member
133a, 133b shaft
135a Y-axis direction tilt motor
135a-1 first rotation information detection sensor
135b X-axis direction tilt 5 motor
135b-1 second rotation information detection sensor
15a, 15b training rod tilt mechanism fixing member
3 training rod
31 limb support member
10 33 fixed stay
35 expansion/contraction mechanism
351 movable stay
353 cover
355 nut
15 357 threaded shaft
359 expansion/contraction motor
359-1 third rotation information detection sensor
37 guide rail
5 training instruction unit
20 7 fixing member
9 chair
91 chair connecting member
78
Kpv, Kiv control gain in speed control
Kpp, Kpv control gain in position control
P(t) position instruction
V(t) speed instruction
S, S' spac5 e
T1 first time period
T2 second time period
T3 third time period
m, n integer
10 t, t1, t2, t3, t4, t5, ta, tb elapsed time
Δt, Δtc time shift amount of position instruction
Δv speed difference
θd deceleration start position (tilt angle corresponding to deceleration start position)
ΔθA, ΔθB, Δθn, Δθn-1, Δθ2, Δθ3, Δθ4, Δθ5, Δθ6, Δθ7 position difference
15 ΔΘn-1, ΔΘn position difference
φ1 first threshold
φ2 second threshold
79

We Claim:
1. A training apparatus for training upper and/or lower limbs of a user in accordance with a
predetermined training program, the training apparatus comprising:
a fixed frame placed on or in the vicinity of a floor;
a training rod supported by the fixed frame in a manner capable of tilting about 5 bout a
predetermined tilting axis with at least one degree of freedom, so as to hold a limb;
a motor configured to tilt the training rod about the tilting axis;
a rotation information detection sensor configured to output an amount of rotation of
the motor;
10 a tilt angle calculating unit configured to calculate a tilt angle of the training rod on
the basis of the amount of rotation of the motor;
a position difference calculating unit configured to calculate a position difference at
an interval of a predetermined first time period, the position difference being a difference
between an actual tilt angle of the training rod and an instructed tilt angle of the training rod
15 instructed by the training program;
a determination unit configured to obtain the position difference calculated by the
position difference calculation unit every time when a predetermined second time period
elapses, and to determine whether or not a position difference change amount generated in
the second time period is a first threshold or lower;
20 a motor drive unit configured to drive the motor so that the position difference is
accumulated and maintained if the determination unit determines that the position difference
change amount generated in the second time period is the first threshold or lower; and
80
a position difference eliminating unit configured to reset the accumulated and
maintained position difference at a preset timing.
2. The training apparatus according to claim 1, wherein the training rod is capable of
expanding and contracting in a longitudinal axis directi5 on.
3. The training apparatus according to claim 1 or 2, wherein the determination unit
determines an error if the position difference change amount generated in the second time
period is higher than the first threshold.
10
4. The training apparatus according to claim 3, further comprising an information providing
unit configured to provide the user with visual or auditory information when the
determination unit determines that an error has occurred.
15 5. The training apparatus according to claim 4, wherein the information providing unit
provides the user with the visual or auditory information when the user has moved the
training rod to reach a preset passing point in a training route set by the training program.
6. The training apparatus according to any one of claims 3 to 5, wherein rotation of the
20 motor is stopped when the determination unit determines that an error has occurred.
7. The training apparatus according to any one of claims 1 to 6, wherein
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the determination unit further obtains the position difference every time when a third
time period elapses, and determines whether or not the position difference change amount
generated in the third time period is a second threshold or lower, and
if the determination unit determines that the position difference change amount
generated in the third time period is the second threshold or lower, the position differenc5 e
eliminating unit resets the accumulated and maintained position difference.
8. The training apparatus according to any one of claims 1 to 7, wherein the position
difference eliminating unit resets the accumulated and maintained position difference when
10 operation of the training rod is stopped.
9. The training apparatus according to any one of claims 1 to 8, further comprising an
instruction generation unit configured to generate a speed instruction including at least an
acceleration instruction for accelerating the motor and a deceleration instruction for
15 decelerating the motor in accordance with the training program, wherein
the motor drive unit controls the motor so as to follow only the speed instruction
when the acceleration instruction is executed.
10. The training apparatus according to claim 9, wherein the speed instruction further
20 includes a constant speed instruction for rotating the motor at a constant speed between the
acceleration instruction and the deceleration instruction, and the motor drive unit further
controls the motor so as to follow only the speed instruction when the constant speed
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instruction is executed.
11. The training apparatus according to claim 9 or 10, wherein
the instruction generation unit further generates a position instruction for controlling
the tilt angle of the training rod in accordance with the training program, a5 nd
the motor drive unit controls the motor so as to follow the speed instruction and the
position instruction when the deceleration instruction is executed.
12. The training apparatus according to any one of claims 9 to 11, wherein the position
10 difference eliminating unit resets the accumulated and maintained position difference when
the deceleration instruction is started.