FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]
AUTONOMOUS DRIVING ASSISTANCE SYSTEM AND OPERATION METHOD
THEREFOR;
MITSUBISHI ELECTRIC CORPORATION, A CORPORATION ORGANISED AND
EXISTING UNDER THE LAWS OF JAPAN, WHOSE ADDRESS IS 7-3,
MARUNOUCHI 2-CHOME, CHIYODA-KU, TOKYO 1008310, JAPAN
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE
INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED

DESCRIPTION
TECHNICAL FIELD
[0001] The present disclosure relates to an autonomous
driving assistance system.
BACKGROUND ART
[0002] An autonomous driving assistance system for
performing autonomous driving of a vehicle such as an
automobile has employed the following measure to ensure
safety during autonomous driving. That is, a plurality of
autonomous driving devices for backup having the same
function are provided in parallel, and the autonomous driving
assistance system is configured to enable, even if an
abnormality occurs in any of these devices, autonomous
driving to be maintained by another normal device
substituting for the abnormal device (see, for example,
Patent Document 1).
[0003] Further, for a case where it is determined that
autonomous driving should be ended, the following function is
adopted in an autonomous driving assistance system in order
to safely make switching to manual driving. That is,
switching is made to manual driving only after: notification
is given to the driver; and consent of the driver, or the
like, is confirmed (see, for example, Patent Document 2).

CITATION LIST
PATENT DOCUMENT
[0004] Patent Document 1: Japanese Patent No. 6212409
Patent Document 2: Japanese Laid-Open Patent
Publication No. 2017-154542
SUMMARY OF THE INVENTION
PROBLEMS TO BE SOLVED BY THE INVENTION
[0005] In these autonomous driving assistance systems, a
driving assistance device for performing autonomous driving
on the basis of information from a sensor includes three
independent calculation devices which respectively calculate
control amounts for a steering device, a drive device, and a
brake device through substantially the same kind of
computation. It is necessary for a comparison determination
unit to determine whether these calculation results are
normal or abnormal, and determine which of the calculation
results is to be used for autonomous driving. Thus, a
problem arises in that an enormous amount of very complex
computation based on various kinds of input information is
needed for calculating these control amounts. In addition,
if calculation is performed through the same kind of
computation by the same CPU, the same miscalculation may be
repeated, and another problem arises from the viewpoint of
diversification.
[0006] The present disclosure has been made to solve the
above problems, and an object of the present disclosure is to
obtain an autonomous driving assistance system that has
redundancy and that is inexpensive and poses no problem in
terms of diversification.

SOLUTION TO THE PROBLEMS
[0007] An autonomous driving assistance system according
to the present disclosure is an autonomous driving assistance
system including: a sensor configured to acquire surroundings
information; a downstream device including an actuator
configured to control a vehicle; and a driving assistance
device configured to calculate a control amount for the
downstream device on the basis of the surroundings
information. The downstream device further includes a
diagnosis unit configured to: perform comparison between at
least two control amounts that include the control amount
calculated in the driving assistance device and a control
amount calculated in the downstream device on the basis of
the surroundings information; and determine, if the control
amounts are equal to each other, that the control amounts are
normal, and determine, if the control amounts are different
from each other, that the control amounts are abnormal.
EFFECT OF THE INVENTION
[0008] The autonomous driving assistance system according
to the present disclosure makes it possible to obtain an
autonomous driving assistance system for vehicles that has
redundancy and that is inexpensive and poses no problem in
diversification.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] [FIG. 1] FIG. 1 is a block diagram of an autonomous
driving assistance system according to embodiment 1.
[FIG. 2] FIG. 2 is a flowchart for the autonomous
driving assistance system according to embodiment 1.
[FIG. 3] FIG. 3 is a hardware diagram of a driving
assistance device in embodiment 1.
[FIG. 4] FIG. 4 is a block diagram of an
autonomous driving assistance system according to embodiment
[FIG. 5] FIG. 5 is a part of a flowchart for the
autonomous driving assistance system according to embodiment
[FIG. 6] FIG. 6 is a part of a flowchart for an
autonomous driving assistance system according to embodiment
[FIG. 7] FIG. 7 is a part of a flowchart for an
autonomous driving assistance system according to embodiment
[FIG. 8] FIG. 8 is a part of a flowchart for an
autonomous driving assistance system according to embodiment
[FIG. 9] FIG. 9 is a part of a flowchart for an
autonomous driving assistance system according to embodiment
[FIG. 10] FIG. 10 is a part of a flowchart for an
autonomous driving assistance system according to embodiment
[FIG. 11] FIG. 11 is a part of a flowchart for an
[FIG. 12] FIG. 12 is a part of a flowchart for an
autonomous driving assistance system according to embodiment
[FIG. 13] FIG. 13 is a block diagram of an
autonomous driving assistance system according to embodiment
[FIG. 14] FIG. 14 is a flowchart for the
autonomous driving assistance system according to embodiment
[FIG. 15] FIG. 15 is a block diagram of an
autonomous driving assistance system according to embodiment
[FIG. 16] FIG. 16 is a flowchart for the
autonomous driving assistance system according to embodiment
[FIG. 17] FIG. 17 is a block diagram of an
autonomous driving assistance system according to embodiment

DESCRIPTION OF EMBODIMENTS
[0010] In the description of embodiments and the drawings,
parts denoted by the same reference characters indicate
identical or corresponding parts.
15 [0011] Embodiment 1
Embodiment 1 of the present disclosure will be
described with reference to FIG. 1 to 3. FIG. 1 is a block
diagram of an autonomous driving assistance system and shows
the entire configuration of the autonomous driving assistance
20 system according to embodiment 1. FIG. 2 is a flowchart for
the autonomous driving assistance system and shows an
operation and drive procedure for the autonomous driving
assistance system according to embodiment 1. FIG. 3 is a
hardware diagram and shows, in the present embodiment, an
25 example of hardware in which control amounts which are
8
commands for actuators are calculated in a driving assistance
device and downstream devices.
[0012]
5 FIG. 1 is a diagram of the entire configuration of
the autonomous driving assistance system. The autonomous
driving assistance system is composed mainly of: sensors 1; a
driving assistance device 10; and a steering device 20, a
drive device 30, and a brake device 40 which are actuators
10 for actually controlling a vehicle. The steering device 20,
the drive device 30, and the brake device 40 are sometimes
referred to as downstream devices in the sense that they
compose the latter half of the inside of the autonomous
driving assistance system.
15 [0013] The sensors 1 are implemented by: cameras and
radars for monitoring areas in front of, behind, and lateral
to the vehicle; a navigator for road information data; and
the like.
The driving assistance device 10 includes: a
20 driving route generation unit 11 which generates a driving
route on the basis of surroundings information acquired by
the sensors 1; and a driving control amount calculation unit
12 which calculates, in order to apply the generated driving
route, control amounts which are commands for the respective
25 downstream devices.
9
[0014] Subsequently to the driving assistance device 10,
the steering device 20, the drive device 30, and the brake
device 40 which are three types of downstream devices are
formed. These downstream devices are different from one
5 another in vehicle-controlling function but have basically
the same configuration. Thus, a structure will be described
based on the steering device 20.
The steering device 20 includes: a steering route
generation unit 21 and a steering control amount calculation
10 unit 22 for calculating a control amount on the basis of the
surroundings information from the sensors 1; and a steering
diagnosis unit 23 which compares this control amount with the
control amount calculated in the driving assistance device 10.
Whether these control amounts are normal or abnormal is
15 determined. If these control amounts are normal, the said
control amount is outputted to an actuator that implements a
steering portion.
[0015] As described above, the autonomous driving
assistance system is composed of the sensors 1, the driving
20 assistance device 10, and the steering device 20, the drive
device 30, and the brake device 40 which are three types of
downstream devices.
[0016]
10
Next, an operation and drive procedure for the
autonomous driving assistance system will be described with
reference to the flowchart for the autonomous driving
assistance system shown in FIG. 2.
5 In FIG. 2, a flow of autonomous driving assistance
is shown from the upper side to the lower side. The steps
from A to B shown in the flowchart are steps of determination
by the diagnosis unit and control of the actuator based on
the determination, which are parts of the flow of autonomous
10 driving assistance. In the other embodiments, examples in
which the steps from A to B are replaced by other steps will
be described.
[0017] First, surroundings information is acquired by the
sensors 1 (step S101), the surroundings information is
15 outputted to the driving assistance device 10, and control
amounts for controlling the actuators are calculated (step
S102). As described with reference to FIG. 1, the driving
assistance device 10 includes the driving route generation
unit 11 and the driving control amount calculation unit 12.
20 The driving route generation unit 11 selects information that
is necessary for executing autonomous driving from, for
example, information transmitted from the sensors 1 about the
distance to a vehicle running in front, a traffic lane and an
obstacle having been detected, the curvature of the road, a
tunnel, and traffic congestion, and generates a driving route.
Besides the above-described information, vehicle running
information such as the vehicle speed, steering wheel
steering, and a brake operation is also transmitted through
the sensors 1 to the driving route generation unit 11 and
used for generating a route.
In the driving control amount calculation unit 12,
control amounts for the actuators composing the respective
downstream devices are calculated on the basis of the driving
route generated by the driving route generation unit 11, and
are outputted.
[0018] Then, also in the downstream devices, control
amounts are calculated on the basis of the surroundings
information (step S103). There are three types of downstream
devices, i.e., the steering device 20, the drive device 30,
and the brake device 40, and a control amount is calculated
in each of the downstream devices.
[0019] Specifically, the steering device 20 includes: the
steering route generation unit 21 which acquires the
surroundings information from the sensors 1 and information
that is characteristic of the steering device 20 such as a
steering wheel torque signal and steering wheel angle
information, and selects and processes necessary information;
and the steering control amount calculation unit 22 which
calculates a control amount.
[0020] The information from the sensors 1 is transmitted
to the drive device 30, and the drive device 30 acquires
information that is characteristic of the drive device 30 and
that is related to the rotation rate, the temperature, the
drive shift position, and the like of the engine or a motor.
A drive route generation unit 31 selects and processes driverelated
information, and a drive control amount calculation
unit 32 calculates a control amount.
[0021] The information from the sensors 1 is transmitted
also to the brake device 40, a brake route generation unit 41
selects and processes brake-related information, and a brake
control amount calculation unit 42 calculates a control
amount.
[0022] In each of diagnosis units 23, 33, and 43, the
corresponding control amount calculated in the driving
assistance device 10 and the control amount obtained in the
downstream device are compared with each other, and whether
or not the control amounts are equal to each other is
determined (step S104).
If these control amounts are different from each
other, switching is made to manual driving (step S110), and
the actuator is controlled through manual driving (step S111).
Meanwhile, if the diagnosis unit determines that
these control amounts are the same control amount, the said
control amount is used to control the actuator (step S105),
and autonomous driving can be performed.
[0023] In control of the actuators through these steps of
autonomous driving, a steering command is outputted to the
steering device 20, an acceleration/deceleration command is
outputted to the drive device 30, and a brake command is
outputted to the brake device 40, thereby performing
operation for steering, the engine or the motor, and the
brake, respectively. As a more specific example, if the
distance to a vehicle running in front is long, an engine
portion 34 is controlled by giving an acceleration command to
the drive device 30. Further, a steering portion 24 is
controlled by giving a steering command to the steering
device according to the tilt and the curvature of the road
in order to move the vehicle toward an edge of the road.
Meanwhile, if the speed is excessively high, a brake portion
44 is controlled by giving a command for braking wheels to
the brake device 40 in order to avoid the risk of running off
the road.
[0024]
Hardware of each of the calculation units included
in the driving assistance device 10, and the downstream
devices 20, 30, and 40 composing the autonomous driving
assistance system is composed of a processor 13 and a storage
device 14, an example of the hardware being shown in FIG. 3.
Although not shown, the storage device includes a volatile
storage device such as a random access memory and a
nonvolatile auxiliary storage device such as a flash memory.
Alternatively, the storage device may include, instead of a
flash memory, a hard disk as the auxiliary storage device.
The processor 13 executes a program inputted from the storage
device 14. In this case, a program is inputted from the
auxiliary storage device via the volatile storage device to
the processor 13. In addition, the processor 13 may output
data such as a calculation result to the volatile storage
device of the storage device 14, or save the data via the
volatile storage device into the auxiliary storage device.
[0025]
Driving assistance devices 10 are devices for
outputting a command of changing the behavior of a vehicle on
the basis of various kinds of information, and do not
directly control actuators that actually drive the vehicle.
However, the contents of the command from the driving
assistance devices 10 are considered to be most important in
terms of safety.
[0026] If an abnormality occurs in generation of a route
or calculation of a control amount in the driving assistance
devices 10, an accident may be caused. In view of this, in
the autonomous driving assistance system according to the
present embodiment, the steering device 20, the drive device
, and the brake device 40 which are the downstream devices
of the autonomous driving assistance system and which are for
operating the actuators also share the role of driving
assistance regarding the respective operation targets in
order to improve the safety of the driving assistance device
and ensure high redundancy and diversity for the
autonomous driving assistance system.
[0027] For example, regarding the steering device 20 for
controlling the steering portion 24, configuring is performed
such that the information from the sensors 1 is transmitted
not only to the driving assistance device 10 but also to the
steering device 20 through a communication line 5. When
having received the information from the sensors 1, the
steering route generation unit 21 generates a route related to steering, and the steering control amount calculation unit 22 calculates a control amount to be transmitted to the steering portion 24. In other words, a part of control of the steering device 20 taken charge of by the driving assistance device 10 is assigned to the steering device 20,
and calculation is performed parallelly.
[0028] The steering route generation unit 21 further
acquires other information that is characteristic of the
steering device 20, e.g., a steering wheel torque signal, a steering wheel angle information, and the like, selects or processes information related to steering, and outputs the
information to the steering control amount calculation unit
22, and the steering control amount calculation unit 22
calculates a control amount.
Then, the steering control amount calculated in the
driving assistance device 10 and the steering control amount
calculated in the steering device 20 are compared with each
other by the steering diagnosis unit 23. If both steering
control amounts are the same calculation result, the said
calculation result can be determined to be normal, and the
steering portion 24 is driven on the basis of the said
calculation result.
[0029] Similarly, the drive device 30 and the brake device
also parallelly perform parts of the function of the
driving assistance device 10.
For example, in the drive device 30, a drive
control amount calculated in the driving assistance device 10
and a drive control amount calculated in the drive device 30
are compared with each other by the drive diagnosis unit 33.
If both drive control amounts are the same calculation result,
the said calculation result is determined to be normal, and
the engine portion 34 is controlled. This autonomous driving
assistance system corresponds to a device called an EMS
(engine management system). Even when the driver has not
manipulated the accelerator, the EMS can cause the vehicle to
run while controlling acceleration/deceleration.
[0030] In the brake device 40, a brake control amount
calculated in the driving assistance device 10 and a brake
control amount calculated in the brake device 40 are compared
with each other by the brake diagnosis unit 43. If both
brake control amounts are the same calculation result, the
said calculation result is determined to be normal, and the
brake portion 44 is controlled. The autonomous driving
assistance system corresponds to a device called an ABS
(antilock brake system). The ABS can give not only a brake
command to cause braking to obtain a predetermined
deceleration but also a fine brake command according to a
vehicle running state without causing the vehicle to spin,
such as a command to cause braking only at the outer front
wheel during cornering at an excessive speed.
[0031] As described above, parallelly to calculation of
the control amounts by the driving assistance device 10,
parts of calculation of control amounts are assigned also to
the steering device 20, the drive device 30, and the brake
device 40 which control the respective actuators. Since the
control amount obtained in the driving assistance device 10
and the control amount calculated in each downstream device
are control amounts calculated by using different CPUs, an
autonomous driving assistance system having excellent
redundancy can be obtained.
[0032] In addition, it is also possible to integrally
control the entire vehicle by comprehensively controlling
5 steering, the engine, and the brake. A system for this
control is called a VDC (vehicle dynamics control) system.
[0033] No calculation capabilities are newly imparted to
the downstream devices in order to obtain the autonomous
driving assistance system according to the present embodiment.
10 Each downstream device is originally mounted with a CPU or
the like for controlling the corresponding actuator, and thus
has a capability of performing calculation. Therefore, there
is no need to increase cost for the downstream devices to
parallelly perform calculation, and thus the autonomous
15 driving assistance system according to the present embodiment
can be obtained at low cost.
[0034] Embodiment 2
Embodiment 2 will be described with reference to
FIG. 4 and FIG. 5. The present embodiment is the same as
20 embodiment 1 in that each downstream device parallelly
performs a part of calculation of control amounts to be
performed by a driving assistance device 100, thereby
improving redundancy. Meanwhile, the present embodiment is
different from embodiment 1 in that control amounts are
19
parallelly calculated in the plurality of downstream devices,
thereby further improving redundancy.
[0035] FIG. 5 is a flowchart for an autonomous driving
assistance system according to the present embodiment, and
5 shows only steps from A to B which are different from those
in the flowchart for the autonomous driving assistance system
according to embodiment 1 shown in FIG. 2. The hardware
configuration is basically the same as that shown in FIG. 3,
and thus description thereof is omitted.
10 [0036] In the present embodiment, a driving route
generation unit 101, a steering route generation unit 201, a
drive route generation unit 301, and a brake route generation
unit 401 which generate routes can select and process the
same information with the same accuracy. Alternatively, the
15 accuracies of some of the route generation units may be
reduced, or only some of the route generation units may be
used, to calculate basic control amounts. Further, the
simplified calculation makes it also possible for a pair of
route generation units and a pair of control amount
20 calculation units to simultaneously calculate two types of
routes and two types of control amounts.
[0037] Timings of acquisition of various information from
the sensors 1 may be different among the downstream devices,
and, if there is a difference in the acquired information, it
25 is considered that: errors are generated; and calculation
20
results of a plurality of control amounts do not take the
same value. In view of this, it is effective that, in each
diagnosis unit: a margin is set for a determination
criterion; and control amounts that fall within the
5 predetermined range are regarded as the same and determined
to be normal.
[0038] The present embodiment takes advantage of a feature
of being able to calculate, in each downstream device, not
only a route and a control amount for the own device but also
10 a route and a control amount for another downstream device.
Accordingly, an autonomous driving assistance system having
further improved redundancy is achieved.
[0039] A configuration of each downstream device will be
described using a configuration diagram that is explained in
15 the present embodiment shown in FIG. 4.
Surroundings information is transmitted from the
sensors 1 through the communication line 5 to a steering
device 200, and a control amount for a steering portion 204
is calculated by the steering route generation unit 201 and a
20 steering control amount calculation unit 202 and transmitted
to a steering diagnosis unit 203.
At the same time, a control amount for an engine
portion 304 is calculated by a drive route generation unit
311 and a drive control amount calculation unit 312 in the
21
same steering device 200, and the control amount is
transmitted through the communication line 5.
[0040] In a drive device 300, a control amount for the
engine portion 304 is calculated by the drive route
5 generation unit 301 and a drive control amount calculation
unit 302 and transmitted to a drive diagnosis unit 303, and a
control amount for a brake portion 404 is parallelly
calculated by a brake route generation unit 411 and a brake
control amount calculation unit 412 and transmitted through
10 the communication line 5. Further, in a brake device 400, a
control amount for the brake portion 404 is calculated by the
brake route generation unit 401 and a brake control amount
calculation unit 402 and transmitted to a brake diagnosis
unit 403, and a control amount for the steering portion 204
15 is parallelly calculated by a steering route generation unit
211 and a steering control amount calculation unit 212 and
transmitted through the communication line 5.
[0041] In addition to the steering control amount obtained
in the steering device 200, the steering control amount
20 calculated in the brake device 400 is transmitted through the
communication line 5 to the steering diagnosis unit 203 of
the steering device 200. Further, a calculation result from
a driving control amount calculation unit 102 is added. Thus,
the three calculation results are compared with one another.
22
Similarly, the two drive control amounts and a
calculation result from the driving control amount
calculation unit 102 are transmitted to the drive diagnosis
unit 303, and the three calculation results are compared with
5 one another. In addition, the two brake control amounts and
a calculation result from the driving control amount
calculation unit 102 are transmitted also to the brake
diagnosis unit 403, and the three calculation results are
compared with one another.
10 [0042] As described above, in the present embodiment, each
diagnosis unit performs determination on the basis of a total
of three calculation results, i.e., the calculation result
from the driving assistance device 100 and the calculation
results from the two downstream devices. Since all of these
15 calculation results are calculated by different CPUs, more
accurate determination can be performed, and false
determination can be inhibited.
[0043] In the present embodiment, determination using the
three calculation results will be described with reference to
20 the flowchart shown in FIG. 5. In the flowchart, the steps
from A to B of the flowchart shown in FIG. 2 have been taken
out and replaced by steps in the present embodiment, and the
steps other than the steps from A to B are the same as those
in the flowchart in FIG. 2.
23
[0044] Whether or not two or more calculation results
among the three calculated control amounts are the same
control amount is determined (step S204). If two or more
control amounts are the same control amount, the said control
5 amount is used to control the actuator (step S205). If two
or more control amounts do not take the same value, i.e., if
all of the three control amounts are different from one
another, switching is made to manual driving (step S210), and
the actuator is controlled through manual driving (step S211).
10 In the present embodiment, since three control
amounts are used, the redundancy is high, and accurate
determination can be performed.
[0045] In the present embodiment, an example has been
described in which: a steering control amount and a drive
15 control amount are calculated in the steering device 200; a
drive control amount and a brake control amount are
calculated in the drive device 300; and a brake control
amount and a steering control amount are calculated in the
brake device 400. However, these combinations are just an
20 example, and the same advantageous effects can be obtained
also with different combinations for calculation. In
addition, although an example in which two types of control
amounts are calculated in each downstream device has been
described, favorable effects can be obtained also if three
24
types of control amounts are calculated in each downstream
device.
[0046] In a case where, for example, two CPUs are mounted
in each of the three downstream devices, two control amounts
5 calculated by the two CPUs in the same downstream device can
be used to perform diagnosis as to the validity of the
calculation results. In order to improve redundancy, it is
important to use calculation results obtained by different
CPUs. Thus, it is possible to perform diagnosis by using,
10 instead of a calculation result from another downstream
device, calculation results obtained by two CPUs in the same
downstream device.
[0047] Embodiment 3
In the present embodiment, a measure against the
15 case where a control amount calculated in the driving
assistance device 10 and a control amount obtained in a
downstream device such as the steering device 20, 200 are
determined to be different from each other by the diagnosis
unit, will be described with reference to the flowchart shown
20 in FIG. 6.
In the flowchart, the steps from A to B of the
flowchart shown in FIG. 2 have been replaced by steps in the
present embodiment, and the steps other than the steps from A
to B are the same as those of the flowchart in FIG. 2.
25
[0048] In a case where the control amount calculated in
the driving assistance device 10 and the control amount
calculated in the downstream device are the same control
amount as a result of comparison therebetween (step S304),
5 the said control amount is used to control the actuator (step
S305).
Meanwhile, in a case where the control amounts are
different from each other, it is necessary to select one of
the control amounts that is safer in terms of the behavior of
10 the vehicle. Here, a smaller control amount indicates a
smaller control amount for the actuator and is considered to
result in a smaller change. Thus, a control amount X1
calculated in the driving assistance device 10 and a control
amount Y1 calculated in the downstream device are compared
15 with each other, and, for example, the actuator is controlled
by using Y1 as the control amount in the case of X1>Y1 while
using X1 as the control amount in the case of X1a (high acceleration), a≥X4>b
10 (low acceleration), b≥X4>c (maintaining the speed), c≥X4>d
(low deceleration), and d≥X4 (high deceleration) (step S905).
[0066] If the diagnosis unit determines that the control
amounts are different from each other, switching is made to
manual driving (step S910) and the actuator is manually
15 controlled (step S911), in FIG. 12. However, the present
disclosure is not limited thereto. For example, combination
with embodiment 3 or the like may be performed. That is,
combination with the method in which a small control amount
considered to result in highest safety is selected may be
20 performed.
[0067] If determination that involves specifying a range
divided into a plurality of levels is performed as described
above instead of obtaining a control amount as a numerical
value, the amount of information to be acquired from the
33
sensors 1 can be reduced, and load of calculation can also be
suppressed.
[0068] Embodiment 10
Embodiment 10 will be described with reference to
5 FIG. 13 and FIG. 14. The present embodiment is the same as
embodiment 2 in that control amounts are parallelly
calculated in the plurality of downstream devices. Meanwhile,
the present embodiment is different from embodiment 2 in that
the autonomous driving system is constructed without being
10 provided with any driving assistance device.
[0069] FIG. 14 is a flowchart for the autonomous driving
assistance system according to the present embodiment. The
hardware configuration is basically the same as that in FIG.
3, and thus description thereof is omitted.
15 [0070] In the present embodiment, the steering route
generation unit 201, the drive route generation unit 301, and
the brake route generation unit 401 which generate routes can
select and process the same information with the same
accuracy. Alternatively, the accuracies of some of the route
generation units may be reduced, or only some of the route
generation units may be used, to calculate basic control
amounts. As shown in FIG. 13, the simplified calculation
makes it also possible to simultaneously calculate a
plurality of types of routes and control amounts by using a
pair of route generation units and a pair of control amount
calculation units.
[0071] Timings of acquisition of various information from
the sensors 1 may be different among the downstream devices,
and there may be a difference in the acquired information.
In this case, it is considered that: errors are generated
also in calculation results of a plurality of control
amounts; and the calculation results do not take the same
value. In view of this, it is effective that, in each
diagnosis unit: a margin is set for a determination
criterion; and control amounts that fall within the
predetermined range are regarded as the same and determined
to be normal.
[0072] In the present embodiment, in each downstream
device, not only a route and a control amount for the own
device but also a route and a control amount for another
downstream device, are calculated. Accordingly, an
autonomous driving assistance system having redundancy can be
achieved without the need of any driving assistance device.
[0073] A configuration of each downstream device will be
described using a configuration diagram that is explained in
the present embodiment shown in FIG. 13.
Surroundings information is transmitted from the
sensors 1 through the communication line 5 to the steering
device 200, and a control amount for the steering portion 204
is calculated by the steering route generation unit 201 and
the steering control amount calculation unit 202 and
transmitted to the steering diagnosis unit 203.
At the same time, a control amount for the engine
portion 304 is calculated by the drive route generation unit
311 and the drive control amount calculation unit 312 in the
same steering device 200, and the control amount is
transmitted through the communication line 5.
[0074] In the drive device 300, a control amount for the
engine portion 304 is calculated by the drive route
generation unit 301 and the drive control amount calculation
unit 302 and transmitted to the drive diagnosis unit 303, and
a control amount for the brake portion 404 is parallelly
calculated by the brake route generation unit 411 and the
brake control amount calculation unit 412 and transmitted
through the communication line 5. Further, in the brake
device 400, a control amount for the brake portion 404 is
calculated by the brake route generation unit 401 and the
brake control amount calculation unit 402 and transmitted to
the brake diagnosis unit 403, and a control amount for the
steering portion 204 is parallelly calculated by the steering
route generation unit 211 and the steering control amount
calculation unit 212 and transmitted through the
communication line.
[0075] In addition to the steering control amount obtained
in the steering device 200, the steering control amount
calculated in the brake device 400 is transmitted through the
communication line 5 to the steering diagnosis unit 203 of
the steering device 200, and the two calculation results are
compared with each other.
Similarly, two drive control amounts are
transmitted to the drive diagnosis unit 303, and the two
calculation results are compared with each other. In
addition, two calculation results of brake control amounts
are transmitted to the brake diagnosis unit 403, and the two
calculation results are compared with each other.
[0076] As described above, in the present embodiment, each
diagnosis unit performs determination on the basis of the
calculation results obtained in the two downstream devices.
Since these calculation results are calculated by different
CPUs, more accurate determination can be performed, and false
determination can be inhibited.
[0077] Determination using the calculation results
obtained in the two downstream devices as in the present
embodiment will be described with reference to the flowchart
shown in FIG. 14. The flowchart is basically the same as the
flowchart shown in FIG. 2 but is different therefrom in that
the step of calculating a control amount in the driving
assistance device (step S102) is not included.
[0078] Whether or not two calculation results of control
amounts calculated in each downstream device are the same
control amount, is determined (step S104). In a case where
the two control amounts are the same control amount, the said
control amount is used to control the actuator (step S105).
In a case where the two control amounts are not the same
control amount and both of the two control amounts are
different from each other, switching is made to manual
driving (step S110), and the actuator is controlled through
manual driving (step S111).
In the present embodiment, accurate determination
can be performed by using the plurality of downstream devices
without providing any driving assistance device.
[0079] In the present embodiment, an example has been
15 described in which: a steering control amount and a drive
control amount are calculated in the steering device 200; a
drive control amount and a brake control amount are
calculated in the drive device 300; and a brake control
amount and a steering control amount are calculated in the
brake device 400. However, these combinations are just an
example, and the same advantageous effects can be obtained
also with different combinations for calculation. In
addition, although an example in which two types of control
amounts are calculated in each downstream device has been
described, favorable effects can be obtained also if three
types of control amounts are calculated in each downstream
device.
[0080] In a case where, for example, two CPUs are mounted
in each of the three downstream devices, two control amounts
calculated by the two CPUs in the same downstream device can
be used to perform diagnosis as to the validity of the
calculation results. In order to improve redundancy, it is
important to use calculation results obtained by different
CPUs. Thus, it is possible to perform diagnosis by using,
instead of a calculation result from another downstream
device, calculation results obtained by the two CPUs in the
same downstream device.
[0081] Embodiment 11
Embodiment 11 will be described with reference to
FIG. 15 and FIG. 16. The present embodiment is the same as
embodiment 2 in that control amounts are parallelly
calculated in the plurality of downstream devices. Meanwhile,
the present embodiment is different from embodiment 2 in
that: two or more driving assistance devices are provided; and the plurality of driving assistance devices and the plurality of downstream devices are used to calculate control amounts.
[0082] FIG. 16 is a flowchart for an autonomous driving
assistance system according to the present embodiment, and shows only the steps from A to B which are different from those of the flowchart for the autonomous driving assistance
system according to embodiment 1 shown in FIG. 2. The hardware configuration is basically the same as that in FIG.
3, and thus description thereof is omitted.
[0083] In the present embodiment, two driving route generation units 101 and 111, the steering route generation unit 201, the drive route generation unit 301, and the brake
route generation unit 401 which generate routes can select and process the same information with the same accuracy.
Alternatively, the accuracies of some of the route generation units may be reduced, or only some of the route generation
units may be used, to calculate basic control amounts. Further, the simplified calculation makes it also possible to simultaneously calculate a plurality of routes and control amounts by using a pair of route generation units and a pair
of control amount calculation units.
[0084] Timings of acquisition of various information from
the sensors 1 may be different among the downstream devices,
and there may be a difference in the acquired information. In this case, it is considered that: errors are generated in calculation results of a plurality of control amounts; and
the calculation results do not take the same value. In view of this, it is effective that, in each diagnosis unit: a margin is set for a determination criterion; and control
amounts that fall within the predetermined range are regarded as the same and determined to be normal.
[0085] In the present embodiment, along with the two driving assistance devices, in each downstream device, not only a route and a control amount for the own device but also a route and a control amount for another downstream device are calculated. Accordingly, even if an abnormality or a fault occurs in one of the driving assistance devices, at
least three calculation results can be compared with one another. Therefore, an autonomous driving assistance system having high redundancy that is equivalent to the redundancy in embodiment 2 is achieved.
[0086] A configuration of each downstream device will be described using the configuration diagram explained in the
present embodiment shown in FIG. 15.
Surroundings information is transmitted from the
sensors 1 through the communication line 5 to the steering device 200, and a control amount for the steering portion 204 is calculated by the steering route generation unit 201 and the steering control amount calculation unit 202 and
transmitted to the steering diagnosis unit 203.
At the same time, a control amount for the engine
portion 304 is calculated by the drive route generation unit
311 and the drive control amount calculation unit 312 in the
same steering device 200, and the control amount is
transmitted through the communication line 5.
[0087] In the drive device 300, a control amount for the
engine portion 304 is calculated by the drive route
5 generation unit 301 and the drive control amount calculation
unit 302 and transmitted to the drive diagnosis unit 303, and
a control amount for the brake portion 404 is parallelly
calculated by the brake route generation unit 411 and the
brake control amount calculation unit 412 and transmitted
through the communication line 5. Further, in the brake
device 400, a control amount for the brake portion 404 is
calculated by the brake route generation unit 401 and the
brake control amount calculation unit 402 and transmitted to
the brake diagnosis unit 403, and a control amount for the
steering portion 204 is parallelly calculated by the steering
route generation unit 211 and the steering control amount
calculation unit 212 and transmitted through the
communication line.
[0088] In addition to the steering control amount obtained
in the steering device 200, the steering control amount
calculated in the brake device 400 is transmitted through the
communication line 5 to the steering diagnosis unit 203 of
the steering device 200. Further, calculation results from
two driving control amount calculation units 102 and 112 are
added. Thus, the four calculation results are compared with
one another.
Similarly, two drive control amounts are further
transmitted to the drive diagnosis unit 303, and the four
calculation results are compared with one another. In
addition, calculation results of two brake control amounts
are further transmitted also to the brake diagnosis unit 403,
and the four calculation results are compared with one
another.
[0089] As described above, in the present embodiment, each
diagnosis unit performs determination on the basis of a total
of four calculation results, i.e., the calculation results
from two driving assistance devices 100 and 110 and the
calculation results from the two downstream devices. Since
these calculation results are calculated by different CPUs,
more accurate determination can be performed, and false
determination can be inhibited. Further, even if one of the
calculation results takes an abnormal value, determination
based on the other three calculation results is performed,
whereby accurate determination can be continued even at the
time of a fault.
[0090] In the present embodiment, determination using four
calculation results will be described with reference to the
flowchart shown in FIG. 16. In the flowchart, the steps from
A to B of the flowchart shown in FIG. 2 have been taken out
and replaced by steps in the present embodiment. The steps
other than the steps from A to B are the same as those of the
flowchart in FIG. 2.
[0091] Whether or not three or more calculation results
among the four calculated control amounts are the same
control amount, is determined (step S1004). If three or more
control amounts are the same control amount, the said control
amount is used to control the actuator (step S1005).
Meanwhile, if three or more control amounts do not take the
same value and all of the four control amounts are different
from one another, or if two of the control amounts take the
same value and the other two control amounts take the same
value that is different from the value taken by the two
control amounts so that determination as to correctness
cannot be performed, switching is made to manual driving
(step S1010), and the actuator is controlled through manual
driving (step S1011). Further, if three of the calculation
results take the same value and the calculation result from
one of the driving assistance devices is different therefrom
(S1006), it is determined that an abnormality is present in
the device which has calculated the different control amount
(S1007).
In the present embodiment, three or more control
amounts are used even if a calculation result from one of the
driving assistance devices is found to be abnormal. Thus,
even if an abnormality occurs, the redundancy is high, and
accurate determination can be performed.
[0092] In the present embodiment, two driving assistance
devices and two downstream devices are used, and thus,
without increase in cost, calculation result diversification
and a higher redundancy are achieved as compared to the case
where only calculation results from the two driving
assistance devices are compared with each other.
[0093] In the present embodiment, an example has been
described in which: a steering control amount and a drive
control amount are calculated in the steering device 200; a
drive control amount and a brake control amount are
calculated in the drive device 300; and a brake control
amount and a steering control amount are calculated in the
brake device 400. However, these combinations are just an
example, and the same advantageous effects can be obtained
also with different combinations for calculation. In
addition, although an example in which two types of control
amounts are calculated in each downstream device has been
described, favorable effects can be obtained also if three
types of control amounts are calculated in each downstream
device.
[0094] In the embodiment, an example has been described in
which the two driving assistance devices calculate two types
of control amounts and each downstream device also calculates
two types of control amounts. However, these combinations
are just an example, and favorable effects can be obtained
also if two or more driving assistance devices are provided.
In addition, although an example in which an
abnormality occurs in calculation by the driving assistance
device has been described, favorable results can be obtained
in the same manner also if an abnormality occurs in
calculation by any of the downstream devices.
[0095] In a case where, for example, two CPUs are mounted
in each of the three downstream devices, two control amounts
calculated by the two CPUs in the same downstream device can
be used to perform diagnosis as to the validity of the
calculation results. In order to improve redundancy, it is
important to use calculation results obtained by different
CPUs. Thus, it is possible to perform diagnosis by using,
instead of a calculation result from another downstream
device, calculation results obtained by the two CPUs in the
same downstream device.
[0096] Embodiment 12
In embodiment 10, an example has been described in
which, in each of the downstream devices 200, 300, and 400,
not only calculation of a route and a control amount for the
own device but also calculation for another one of the
downstream devices is performed as shown in FIG. 13.
In the present embodiment, a configuration in which
embodiment 10 is further developed and calculation for the
other two downstream devices is performed as shown in FIG. 17,
will be described.
[0097] In each of the downstream devices 200, 300, and 400,
not only a route and a control amount for the own device but
also routes and control amounts for the other two downstream
devices are calculated. Each calculation result is
transmitted through the communication line 5 to the
10 corresponding downstream device and used, by the diagnosis
unit of the downstream device, for determination as to
whether an abnormality has occurred in calculation.
[0098] A calculation result for the own device and
calculation results for the other two downstream devices are
used, and thus, even though this configuration uses only the
downstream devices, the three calculation results can be
compared with one another. Accordingly, a favorable
autonomous driving assistance system having a higher
redundancy can be formed.
[0099] In a case where, for example, two CPUs are mounted
in each of the three downstream devices, two control amounts
calculated by the two CPUs in the same downstream device can
be used to perform diagnosis as to the validity of the
calculation results. In order to improve redundancy, it is
important to use calculation results obtained by different
CPUs. Thus, it is possible to perform diagnosis by using,
instead of a calculation result from another downstream
device, calculation results obtained by the two CPUs in the
same downstream device.
[0100] Although the disclosure is described above in terms
of various exemplary embodiments and implementations, it
should be understood that the various features, aspects and
functionality described in one or more of the individual
embodiments are not limited in their applicability to the
particular embodiment with which they are described, but
instead can be applied, alone or in various combinations to
one or more of the embodiments of the disclosure.
It is therefore understood that numerous
modifications which have not been exemplified can be devised
without departing from the scope of the specification of the
present disclosure. For example, at least one of the
constituent components may be modified, added, or eliminated.
At least one of the constituent components mentioned in at
least one of the preferred embodiments may be selected and
combined with the constituent components mentioned in another
preferred embodiment.
DESCRIPTION OF THE REFERENCE CHARACTERS
[0101] 1 sensor
25 5 communication line
10, 100, 110 driving assistance device
11, 101, 111 driving route generation unit
12, 102, 112 driving control amount calculation
unit
5 13 processor
14 storage device
20, 200 steering device
21, 201, 211 steering route generation unit
22, 202, 212 steering control amount calculation
10 unit
23, 203 steering diagnosis unit
24, 204 steering portion
30, 300 drive device
31, 301, 311 drive route generation unit
15 32, 302, 312 drive control amount calculation unit
33, 303 drive diagnosis unit
34, 304 engine portion
40, 400 brake device
41, 401, 411 brake route generation unit
20 42, 402, 412 brake control amount calculation unit
43, 403 brake diagnosis unit
44, 404 brake portion

We Claim:
[1] An autonomous driving assistance system comprising:
a sensor configured to acquire surroundings
information;
a downstream device including an actuator
configured to control a vehicle; and
a driving assistance device configured to calculate
a control amount for the downstream device on the basis of
the surroundings information, wherein
the downstream device further includes a diagnosis
unit configured to:
perform comparison between at least two control
amounts that include
the control amount calculated in the
driving assistance device and
a control amount calculated in the
downstream device on the basis of the surroundings
information; and
determine, if the control amounts are equal to
each other, that the control amounts are normal, and
determine, if the control amounts are different from each
other, that the control amounts are abnormal.
[2] An autonomous driving assistance system comprising:
a sensor configured to acquire surroundings
information; and
a plurality of downstream devices including
actuators configured to control a vehicle, wherein
one downstream device among the plurality of
downstream devices further includes a diagnosis unit configured to:
perform comparison between at least two control
amounts that include
a control amount calculated in the one
downstream device on the basis of the surroundings information and a control amount calculated in a downstream device that is different from the one downstream device among the plurality of downstream devices on the basis
of the surroundings information; and
determine, if the control amounts are equal to
each other, that the control amounts are normal, and determine, if the control amounts are different from each
other, that the control amounts are abnormal.
[3] The autonomous driving assistance system according
to claim 1 or 2, wherein the downstream device includes a steering device, a drive device, and a brake device.
[4] The autonomous driving assistance system according to claim 1, wherein calculation of the control amount in the driving assistance device is performed by: a driving route generation unit configured to acquire the surroundings information via the sensor and generate a travel route; and a
driving control amount calculation unit configured to calculate the control amount for the downstream device.
[5] The autonomous driving assistance system according
to any one of claims 1 to 4, wherein calculation of the control amount in the downstream device is performed by: a route generation unit configured to acquire the surroundings information via the sensor and generate a travel direction; and a control amount calculation unit configured to calculate
the control amount for the downstream device.
[6] The autonomous driving assistance system according
to claim 1 or 4, wherein comparison by the diagnosis unit is performed for, in addition to the control amount calculated in the driving assistance device and the control amount calculated in the downstream device, the control amount calculated in a downstream device that is different from the downstream device.
[7] An operation method for the autonomous driving
assistance system according to any one of claims 1 to 6, the operation method comprising determination by the diagnosis unit, wherein, if the control amounts are determined to be different from each other, a control amount that allows safety of the vehicle to be prioritized is selected from
among the control amounts, and the actuator is controlled by using the control amount.