[0001]The present invention, when the driver and the steering system of the vehicle is steering, the assist mode for controlling the motor that applies assist force to a steering system, in accordance with the target steering angle given at any time from the vehicle when the vehicle is autonomous motor It relates to an electric power steering apparatus having an automatic mode for controlling the, in particular by using the angle information of the motor with more torque sensor downstream estimated steering wheel angle with a second or higher order resonant filter according to the frequency response of the hands and, hand ON / OFF determination by performing a comparison between the estimated steering wheel angle and the actual steering wheel angle let go state (steering hand (hand) gripping (ON) or hands (hands) gripping (ON), gripping the steering performed not state (OFF) determined with), without being affected by noise involved in free vibration system including the resonance of the steering wheel Relates to an electric power steering device for judging accurate manual input.
BACKGROUND
[0002]
　Explaining shows the general construction of an electric power steering apparatus in FIG. 1, the handle (steering wheel) 1 of column shaft (steering shaft, the steering wheel shaft) 2 is a reduction gear 3, universal joints 4a and 4b, a pinion rack mechanism 5 , via tie rods 6a, the 6b, which is further connected steered wheels 8L, the 8R via the hub unit 7a, 7b. In addition, the column shaft 2, a steering angle sensor 14 for detecting the torque sensor 10 and the steering angle θh detected steering torque of the steering wheel 1 is provided, the motor 20 for assisting the steering force of the steering wheel 1, the speed reduction mechanism as reduction gear via a (reduction ratio 1 / N) 3 is connected to the column shaft 2. The control unit (ECU) 100 for controlling the electric power steering apparatus, the electric power from the battery 13 is supplied, the ignition key signal is inputted through the ignition key 11. Control unit 100 performs calculation of the assist (steering assist) command current command value based on the vehicle speed Vs detected by the steering torque Tr and the vehicle speed sensor 12 detected by the torque sensor 10, compensation for the current command value controlling the current supplied to the motor 20 by the voltage control command value Vref subjected to. Incidentally, the steering angle sensor 14 for detecting a steering angle θh is not mandatory and may not be disposed.
[0003]
　The control unit 100, CAN (Controller Area Network) 40 for exchanging various kinds of information of the vehicle and is connected, the vehicle speed Vs is also possible to receive from CAN40. Further, the control unit 100, communications other than CAN40, an analog / digital signals, even non CAN41 for exchanging radio waves connectable.
[0004]
　In such an electric power steering device, it is constituted by the control unit 100 mainly CPU (including MPU or MCU etc.), indicating the general functions executed by a program in the CPU, for example, in FIG. 2 It has a configuration as shown.
[0005]
　To explain the function and operation of the control unit 100 with reference to FIG. 2, the vehicle speed Vs from the steering torque Tr and the vehicle speed sensor 12 from the torque sensor 10 is inputted to the current command value calculating section 101, a current command value computing part 101 calculates a current command value Iref1 using an assist map or the like based on the steering torque Tr and the vehicle speed Vs. The calculated current command value Iref1 in the adding section 102A, is added to the compensation signal CM from the compensator 110 to improve the characteristics, the current command value Iref2 of the addition is limited to a maximum value at the current limiting unit 103, maximum current command value is limited to values ​​Irefm is inputted to the subtraction unit 102B, is subtracted motor current detection value Im.
[0006]
　A subtraction result of the subtraction unit 102B deviation ΔI (= Irefm-Im) is a current control PI (proportional integral) or the like by the PI control unit 105, the voltage control command value Vref which is current control to the PWM control unit 106 is inputted is calculated the Duty, via the inverter 107 by the PWM signal calculated the Duty to PWM drive the motor 20. Motor current value Im of the motor 20 is detected by a motor current detector 108, it is subtracted input to the subtracting unit 102B and feedback. Furthermore, from the rotation sensor 20A such as a resolver connected to the motor 20, obtains an electrical angle signal θe of the motor 20.
[0007]
　Compensation unit 110 adds the inertia compensation value 112 for self-aligning torque (SAT) 113 which is detected or estimated by the adding unit 114 adds the convergence control value 111 in further addition unit 115 to the addition result, the input to the addition section 102A of the addition result as a compensation signal CM, implementing the performance improvement.
[0008]
　In such an electric power steering apparatus, Advanced Driver Assistance System (ADAS: Advanced Driver Assistance System) is one of the areas the fastest growing in automotive applications. ADAS think the future of the car society, prevention in has been developed in order to improve the safety and convenience systems, prospects of or bad situation, to detect the risk of accidents caused by such inattentive driving, accidents before they happen or be a thing of the order to mitigate. "Cognitive" in order to drive the vehicle, "determination", it becomes necessary operation such as "operation", focuses on the fact that to ensure the safety for the series of operations, ADAS is the driver provide support. As a technique that leads to future automatic operation technology, the driver determines whether the manual input gripping the steering wheel, i.e. there is a technique for detecting the hand ON / OFF (Hands-ON / OFF), the improvement in the detection accuracy it has become increasingly important.
[0009]
　As detection technique of the conventional hand ON / OFF, for example, it is disclosed in JP-A-8-337181 (Patent Document 1) and JP-A-11-208498 (Patent Document 2). Automatic steering apparatus disclosed in Patent Document 1 is according torsion torque Tt during the automatic steering input point and the handle is provided with a mechanism for automatic steering is canceled when a predetermined value or more, the automatic steering so that it not released by mistake.
[0010]
　By detecting the torsional torque Tt associated with the torsion bar, the general configuration for determining the manual input is 3, and the torque sensor unit 200 for detecting the torque Tt twisted column shaft 2 is provided there. A configuration using the torsion bar 201 is disposed in the torque sensor unit 200, twisting the stub shaft 202 of the input-side column shaft through a torsion bar 201 (IS) 2A and the output side column shaft (OS) 2B, aluminum formed by manufacturing the sleeve 203 or the like, it is detected as the torque Tt torsionally voltage induced in the coil 204 which is wound around the outer peripheral surface of the aluminum sleeve 203. A steering wheel 1 side input column shaft (IS) 2A against Toshobba 201 disposed in the torque sensor unit 200, a pinion side and the output side column shaft (OS) 2B, the worm and the worm on the output side column shaft 2B reduction gear consisting of a wheel (reduction ratio 1 / N (N> 1.0)) 3 is provided. A worm wheel mounted on the output side column shaft 2B is a worm which is connected to an output shaft of the motor 20 is driven to rotate at the speed reduction ratio 1 / N, the motor 20 is controlled by the control unit (ECU) 100.
[0011]
　In this structure, the torque detection value exceeds a predetermined value T 0 , even more, when the rotational angular acceleration θ of the column shaft 2 'is greater than a predetermined value A has a structure in which automatic steering is not released. Further, automatic steering apparatus disclosed in Patent Document 2, in order to reliably release the automatic steering to accurately detect the manual steering by the driver during automatic steering, the torque Tt torsion generated in the column shaft 2, the steering wheel 1 based on the difference between the torque Ti required for rotating accelerating the inertia moment Ih until the steering angle acceleration [theta] h ", it is determined to cancel the automatic steering.
[0012]
　That is, if described with reference to the model diagram shown in FIG. 4, the handle 1 is opened, the input-side column shaft 2A angle θ from the reduction gear 3 side by the motor 20 O when driven rotated by the handle 1 is in the inertia When rotated by the angle θh overcome, Kh torsional rigidity of the input-side column shaft 2A (spring constant), the moment of inertia of the steering wheel 1 and Ih, the number 1 is established below.
[0013]
　(Number
1) Ih × [theta] h "+ Kh ([theta] h-theta O ) = 0
However, [theta] h" is the rotation angular acceleration is second-order differential value of the angle [theta] h.

In this case, the torque Tt twisting according to the input side column shaft 2A is expressed by the following Expression 2.
[0014]
　(Equation
2) Tt = Kh × (theta O -h)
from the equations 1 and 2, number 3 is established below.
[0015]
　(Equation 3)
"Tt = Ih × [theta] h

　as represented by the number 3, torsion torque Tt is the angular acceleration [theta] h handle 1" becomes possible to estimate by detecting. When the automatic steering is being performed, the driver rotates the steering wheel 1 against the automatic steering force, the torque Tt occurs twisted on the input side column shaft 2A. The twisting torque Tt is the moment of inertia Ih of the steering wheel 1 rotation angular acceleration [theta] h "torque required to accelerate to Ti (= Ih × θh") , since the sum of the manual steering torque Td by the driver, the following the number 4 is established.
[0016]
　(Equation
4) Tt = Ti + Td = Ih × [theta] h "+ Td

　As is apparent from the equation 4, the difference between the torsion torque Tt of the input-side column shaft 2A, a torque Ti required for rotating accelerating the handle 1 (TT- Ti) is equal to the manual steering torque Td by the driver, the number 5 is established below.
[0017]
　(Number
5) Tt-Ti = Tt-Ih × [theta] h "= Td

Accordingly, by obtaining the torque difference (Tt-Ti), to determine the presence or absence of manual steering of the driver during automatic steering (manual input) can.
CITATION
Patent Document
[0018]
Patent Document 1: JP-A-8-337181 JP
Patent Document 2: JP 11-208498 JP
Summary of the Invention
Problems that the Invention is to Solve
[0019]
　In the automatic steering device disclosed in Patent Documents 1 and 2, the column shaft to detect a torsional torque Tt generated (steering shaft), steering in torque Ti from the moment of inertia Ih of the steering angle acceleration theta "the handle 1 determined to implement compared (Tt-Ti) in. Thereafter, the release or set the automatic steering operation of the steering as required. Therefore, the portion corresponding to the moment of inertia Ih is upstream of the load side to be assisted since it is determined by information (determined by the tuning work) it is required second derivative to determine the certain. angular acceleration theta "is a problem that is easily affected by noise involved in the free vibration system according to the spring constant Kh or the like, very there is noise many become problem to. If the differential in the change point of the steering, especially noise increases.
[0020]
　Further, the automatic steering system disclosed in Patent Document 1 and Patent Document 2 is to determine the manual input torque detection value (torsional torque), not at all mention the method carried out in the column axis angle.
[0021]
　Furthermore, there is a method of detecting manual input by providing a touch sensor in the handle, together with costly the mounting of the touch sensor, detection accuracy by the mounting and the environment, such as gloves, there is a problem that deteriorates.
[0022]
　The present invention has been made on the basis of the circumstances as described above, an object of the present invention, without causing an increase in cost, without being affected by noise involved in free oscillation system by the spring constant and the like, the influence of the disturbance determining accurately manual input (hand oN / OFF) by receiving no situation is to provide an electric power steering device capable. A case that gripped the steering both hands or with one hand and hand ON (manual input there), is a case that is not gripping the steering wheel and hand OFF (no manual entry).
Means for Solving the Problems
[0023]
　The present invention is provided with a torsion bar to the column shaft connected to the handle, through a reduction gear mechanism, with drive control of the motor for applying the assist torque to a steering mechanism of a vehicle by the current command value, switches the assist mode and automatic mode relates to an electric power steering apparatus having a function, the object of the present invention, a torsion bar torsion angle calculating unit for determining the angle twist the torsion bar based on the torque information on the torsion bar, a predetermined arithmetic expression from the electrical angle signal of the motor an output-side column shaft relative angle generator outputting the output side relative angle with the actual steering wheel angle calculating unit for determining the actual steering wheel angle based on the torsion bar torsion angle and the output-side relative angle, the output side relative angle a resonant filter determining an estimated steering wheel angle hands-off state from the actual steering wheel angle 及 The deviation angle of the estimated steering wheel angle parted state is achieved by and a hand ON / OFF determination unit determines hand ON when the time becomes a predetermined angle or more has continued for the predetermined period of time one or more.
[0024]
　The above-described object of the present invention, the hand ON / OFF determination unit, after the determination of the hand ON, the time the deviation angle is less than the predetermined angle is determined hand OFF when continued for a predetermined time period 2 or more by, or torque information on the torsion bar, by a torque twisting about the column axis angle or the torsion bar about the handle, or the torsion bar torsion angle calculation unit, the torsion type the torque, the torsion bar wherein by a torsion bar torsion angle calculating unit for calculating a torsion bar torsion angle, or the torsion bar torsion angle calculation unit, a torque sensor detecting the input side column angle and torque sensor detection output column is divided by the spring constant enter the angle, using the spring constant of the torsion bar By serial is torsion bar torsion angle generator for generating a torsion bar torsion angle, or the output-side column shaft relative angle generator, the electrical angle signal later with the anti-rollover process, wherein the predetermined arithmetic expression by and outputs an output side relative angle, or the predetermined arithmetic expression is, the motor of the pole pairs in the electric angle signal, by a calculation formula of multiplying the reduction ratio of the speed reduction mechanism, or the resonant filter, the reproduced resonance of the handle, the estimated steering wheel angle is the actual steering wheel angle of the hand-release state obtained by inputting the output side column angle when steering from the output column axis actual wound When the fact that almost the same as made properties, or the resonance filter is the second or higher order LPF (low pass filter) And by, it is more effectively achieved.
The invention's effect
[0025]
　According to the electric power steering apparatus of the present invention, by using the angle information or the torque detection value of the motor with more torque sensor downstream (the twisting torque) estimates the steering wheel angle by the resonance filter according to the frequency response of the hands, since performing determination hand oN / OFF based on the comparison (difference) between the actual steering wheel angle, without being affected by noise involved in free vibration system including the resonance of the handle, the determination of accurate manual input It can be performed. Since no performing second-order derivative in the present invention, the determination is simple, not easily influenced by noise.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026]
Is a block diagram showing an outline of FIG. 1 the electric power steering system.
Is a block diagram showing a configuration example of a control system of FIG. 2 the electric power steering apparatus.
3 is a diagram showing a mechanism of a column type steering of the steering shaft (column shaft).
4 is a model diagram for analyzing the force applied to the steering shaft (column shaft).
[5] the torsion bar and the steering wheel angle, a mechanism diagram showing the relationship between the output side column angle.
6 is a diagram showing the relationship between the mounting examples and column angle, steering wheel angle sensor.
It is a block diagram showing a configuration example of a manual input determining unit according to FIG. 7 present invention.
8 is a block diagram showing a part of a configuration example when entering a twisting torque.
It is a Bode diagram showing a characteristic example of a resonant filter used in FIG. 9 present invention.
Is a block diagram showing a configuration example of FIG. 10 Hand ON / OFF determination unit.
11 is a flowchart showing an operation example of the present invention.
Is a time chart showing an example of a steering system angular characteristics when touching the [12] handle.
Is a time chart showing an example of a steering system angular characteristics when not touched [FIG. 13] handle.
DESCRIPTION OF THE INVENTION
[0027]
　Any time from the vehicle when the driver steering system of a vehicle provided with a torsion bar to the column shaft handle is connected during steering, the assist mode for controlling the motor that applies assist force to the steering system, the vehicle is autonomous the electric power steering system having an automatic mode for controlling the motor in accordance with the target steering angle given, there is a detection technique of the determination whether the driver is holding the steering (hand oN / OFF or manual input), in the detection, improving detection accuracy that is not affected by disturbance noise have become increasingly important.
[0028]
　In the present invention, instead of the hand ON / OFF determination that was determined by the conventional torque system, we propose a determining method in an angle-based using no differential. Specifically using the angle information of the assist motor of the EPS downstream from the torque sensor, a steering wheel angle by the resonance filter designed according to the frequency response of the hands (e.g. second or LPF (low pass filter)) estimated, and the actual steering wheel angle calculated from the angle information or torsion torque and the electrical angle signal of the motor about the column axis, based on the deviation angle between the estimated steering wheel angle estimated openly state, the angle threshold and time threshold determination of the handle ON / OFF by performing a comparison of two stages, i.e. it is determined manually. In the present invention, the case holding the steering both hands or with one hand and hand ON (there is manual input), is a case that is not gripping the steering wheel and hand OFF (no manual entry). Without using a motor angular velocity and motor angular acceleration with differential operation, without being affected by noise involved in the free vibration system by rigid torsion including a resonance such as a handle, it is determined accurate handle ON / OFF It is way.
[0029]
　The present invention is, turning the output side column shaft 2B in a state of disconnecting the steering system from the universal joint 4a in FIG. 1 (giving the angle), not touch the case and the handle 1, which touch the handle 1 in the case, the vibration characteristic appearing on the input side column shaft 2A is based on different phenomena. 5, the torsion bar 23 and the handle angle [theta] h, a mechanism diagram showing the relationship between the output-side column angle .theta.c, when the torsion bar torsion angle and [theta] d, 6 is established below.
[0030]
　(Number 6)
　　[theta] h = .theta.c + [theta] d

　and FIG. 12, the characteristics when touching a hand to the handle 1, steer (~ t1), the holding steering state (t1 ~ t2), switching back (t2 ~ t3), steering hold the state (t3 ~), shows the actual steering wheel angle (input side column angle) with respect to a change in the output-side column angle .theta.c. Similarly, FIG. 13, a characteristic when the steering wheel 1 does not touch, for example, the right turn (~ t1), the holding steering state (t1 ~ t2), the left turn (t2 ~ t3), the holding steering state (t3 ~ ) will show the actual wheel angle (input side column angle) with respect to a change in the output-side column angle .theta.c. Differences in the characteristics of FIGS. 12 and 13 is due to the torsion bar torsion angle θd of the torsion bar vibration, it is possible to determine the letting go of the handle (hand OFF) or touch the hand (the hand ON).
[0031]
　Hereinafter, the embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0032]
　First, a description is shown in FIG. 6 the arrangement relationship various sensors in the case of determination using the angle information.
[0033]
　The input side column shaft 2A of the handle 1 side of the column shaft 2 provided with a torsion bar 23, the Hall IC sensor 21 and torque sensor input side rotor 20 ° rotor sensor 22 as an angle sensor is mounted. Hall IC sensor 21 outputs a AS_IS angle θn of 296 ° cycle. 20 ° rotor sensor 22 attached to the handle 1 side from the torsion bar 23, the input-side column angle signal 20 ° period θh1 (TS_IS angle 1) and θh2 (TS_IS angle 2) outputs, the input-side column angle signal θh1 is input to the angle calculation unit 50. Further, the output side column shaft 2B of the column shaft 2, 40 ° rotor sensor 24 of the torque sensor output side rotor is mounted, the output side column angle signal from the 40 ° rotor sensor 24 θc1 (TS_OS angle 1) and θc2 (TS_OS angle 2) is output, the output-side column angle signal θc1 is input to the angle calculation unit 50. Input column angle signal θh1 and the output-side column angle signal θc1 is the absolute angle by the angle calculation unit 50 together are calculated, the torque sensor detects the input side column angle θth and the torque sensor detection output column angle θtc is output.
[0034]
　When determining the torque Tt torsion from the torque sensor detects the input side column angle θth and the torque sensor detection output column angle θtc is the spring constant of the torsion bar 23 when the Kh, can be obtained from the following Expression 7.
[0035]
　(Number 7)
　　Tt = Kh ([theta] th-Shitatc)

　Further, when determining seeking torque Tt torsion from the torque detection value is directly obtained torque Tt twist from the configuration of Figure 3 described above.
[0036]
　Configuration of manual input determining unit of the present invention can be applied to the case of directly detecting torque Tt twist from the configuration of FIG. 3, to the case of obtaining the torque Tt twist from the configuration of FIG. First, will be described with Figure 7 shows the embodiment of the case of obtaining the torque Tt twist from the configuration of FIG.
[0037]
　A torsion bar torsion angle generation unit 120 for generating a torsion bar torsion angle θd by entering the torque sensor detection input column angle θth and the torque sensor detection output column angle Shitatc, an electrical angle signal θe of the motor from the rotation sensors 20A actual handle for outputting an output side (OS) the relative angle generator 150 outputs the input to the output side (OS) relative angle [theta] t, the actual steering wheel angle θhr adds the torsion bar torsion angle θd and the output side relative angle [theta] t an adder 121 as an angle calculator, the output side relative angle θt and the resonant filter 140 for outputting an estimated steering wheel angle θhe the hands-off state by entering the deviation angle θde by subtracting the estimated steering wheel angle θhe from the actual steering wheel angle θhr a subtraction unit 122 for obtaining the configuration in the hand oN / OFF determination unit 130 determines a hand oN / OFF on the basis of the deviation angle θde It has been.
[0038]
　Torsion bar torsion angle generator 120, in this example seeking torsion bar torsion angle [theta] d on the basis of the torque sensor detection input column angle θth and the torque sensor detection output column angle θtc shown in FIG. 6 (θd = θth- Shitatc or θd = | θth-θtc |) is able to determine the torsion bar torsion angle [theta] d from the detected torsional torque Tt by the torque sensor unit 200 shown in FIG. Configuration in this case is 8, the detected torsion torque Tt enter the torsion bar torsion angle calculating unit 120A, obtains a torsion bar torsion angle θd by calculating the following Equation 8.
[0039]
　(Number 8)
　　[theta] d = Tt / Kh

　Further, the output side relative angle generator 110 anti-roll-over process in the motor electric angle scale (waveform processing (e.g. an angle signal of sawtooth waves to process continuous angle signal)) to performed, and outputs an output side relative angle θt in accordance with the following equation (9).
[0040]
　(Number 9)
　　[theta] t = .theta.e × 1 / number of pole pairs × speed reduction ratio
　　, however, is extremely logarithm motor pole pairs, the reduction ratio of the reduction ratio speed reduction mechanism.

　Incidentally, when the tuning from the output side, the friction existing in the unit, motor loss torque, the spline portion of the motor shaft backlash, inertia, etc. preload input-side bearing is associated.
[0041]
　Resonant filter determining an estimated steering wheel angle θhe of letting go state 140, using the data reproducing resonance of the steering wheel 1 by turning the steering from the output side column shaft 2B in actual, the input-side column angle handle angle θh and the output side column take the frequency response from the measurement result of the angle .theta.c, it is designed resonant filters accordingly. Bode diagram showing a characteristic example of a resonant filter 140 is a characteristic of FIG. 9 B (solid line), the gain of the resonance filter 140 flat to around 3 Hz, general secondary at 10Hz vicinity LPF (dashed characteristic A ) it is larger convex than, have a little lower than about 20Hz or less in the general second-order LPF (dashed characteristic a). The phase of the resonance filter 140, about 20Hz general second-order LPF (dashed characteristic A) smaller later than the following, more general second-order LPF about 20Hz or less (dashed characteristic A) delay is larger. That is, the actual machine or on the platform to simulate the actual vehicle test apparatus or the like, while the energized ECU, openly state the handle 1 does not touch at all, (actually release the portion of the universal joint 4a in FIG. 1 Te by providing manual input) Turn the output side column shaft 2B, to measure the steering wheel angle θh and the output column angle .theta.c. (Helix angle θd by the torque sensor is directly determined) torsion angle θd from the torque Tt torsion seek, handle angle θh is obtained by adding the output side column angle .theta.c (see 6). The filter design, using the output-side column angle θc and the handle angle θh of actual data such as on the platform to simulate the actual or real vehicle test device. The handle angle [theta] h, is also included resonance of the handle. For the determination of openly, the output-side column angle θc ideal filter input results Shitahe (estimated steering wheel angle of letting go state) Should be handle angle [theta] h, in order to reproduce the resonance, the second-order filter be required. The designed resonant filter 140 is adjusted to match the estimated steering wheel angle θhe of letting go state the handle angle θh of the actual data, as a result the characteristics of FIG.
[0042]
　The waveform of the actual output-side column angle θc is shown in FIGS. 12 and 13, the actual steering wheel angle θhr contrast vibration waveform is observed by such a change point of the steering. Estimated steering wheel angle θhe of letting go state from the resonant filter 140, noise is removed by the resonance filter 140 which is designed by the tuning input to the subtraction unit 122.
[0043]
　Configuration of the hand ON / OFF determination unit 130 is as shown in FIG. 10, for example, deviation angle Shitade obtained by the subtraction unit 122 is input to the absolute value unit 131, absolute value deviations angle | Shitade | is inputted to the angle comparison unit 132 and compared with a threshold angle θth that is set in advance. That is, whether the following expression 10 is satisfied.
[0044]
　(Number 10)
　　| Shitahr-Shitahc | = | Shitade | ≧ [theta] th

　when the number 10 is established, the angle comparison unit 132 outputs the angle establishing signal AE. The angle establishing signal AE is input to the Establishment comparison unit 133 and the unsatisfied time comparison unit 134, the establishment time comparison section 133 determination signal indicating the hand ON when the angle establishing signal AE continues preset The times than threshold value T1 outputs DS1, determination signal DS1 is output as determined signal DS hand ON via the OR circuit 135. Further, after the determination is not satisfied time comparison unit 134 hands ON, if not satisfied state number 10 has continued for the time threshold T2 which is set in advance, and outputs a determination signal DS2 indicating a hand OFF, the determination signal DS2 is OR circuit 135 It is output as the judgment signal DS of hand OFF through. Purpose of holding the hand ON state a predetermined time, even if the driver touches the steering wheel, when the angle difference between the input side and the output side does not appear (e.g., good road conditions, such as traveling on a straight line) and instantaneous when such a hands-off, because it is necessary to avoid determined as a hand OFF.
[0045]
　Although in the example of FIG. 10 is compared with one threshold angle [theta] th to the absolute value of the deviation angle Shitade, it may be compared with positive and negative threshold angle ± [theta] th without absolute values.
[0046]
　In such a configuration will be described with reference to the flowchart of FIG. 11. An operation example.
[0047]
　First inputs a torque sensor detecting the input side column angle θth and the torque sensor detection output column angle θtc the torsion bar torsion angle generation unit 120 (step S10), and the torsion bar torsion angle generator 120 generates a torsion bar torsion angle θd (step S11). Torsion bar torsion angle θd is input to the adder 121. In the case of Figure 8 to enter the torque Tt twist shown in Figure 3, the torsion torque Tt enter the torsion bar torsion angle calculating unit 120A, a torsion bar torsion angle calculating unit 120A calculates a torsion bar torsion angle θd .
[0048]
　Also, enter the motor electrical angle θe output side relative angle generating unit 110 (step S12), the output side relative angle generating unit 110 generates an output side relative angle [theta] t (step S13), and adds the output side relative angle [theta] t input to the section 121 and the resonance filter 140. Then, the addition unit 121 calculates the actual steering wheel angle θhr adds the torsion bar torsion angle θd and the output side relative angle [theta] t (step S14), and the estimated steering wheel angle θhe resonant filter 140 processes the output side relative angle [theta] t calculating a (step S15), and inputs each subtraction unit 122. Subtraction unit 122 calculates the deviation angle θde by subtracting the estimated steering wheel angle θhe the hands-off state from the actual steering wheel angle Shitahr (step S16), and input to the handle ON / OFF determination unit 130.
[0049]
　In Handle ON / OFF determination unit 130, first, the absolute magnitude of at binarization unit 131 deviation angle θde | θde | look (step S20), and determines whether the number 9 is established at the angle comparison unit 132 (step S21). If the number 9 is not satisfied and returns to the step S20, the angle comparison unit 132 when the number 9 is satisfied and outputs the angle establishing signal AE (step S22). Angle establishing signal AE is inputted to the Establishment comparison unit 133, the duration is compared to the time threshold value T1 (step S23). Establishment comparison unit 133 outputs a determination signal DS1 when the angle establishing signal AE is the duration threshold value T1 or more (step S24), and the determination signal DS1 is determined signal DS via the OR circuit 135 is outputted (step S25 ). Further, after the determination is not satisfied time comparison unit 134 hands ON, unsatisfied condition number 9 it is determined whether to continue for a time threshold T2 (step S26), the determination signal when the unsatisfied condition becomes time threshold T2 or more outputs DS2 (step S27), the determination signal DS2 is output as determined signal DS via the OR circuit 135 (step S28).
[0050]
　12, the actual machine or on the platform to simulate the actual vehicle test apparatus or the like, while the energized ECU, the estimated steering wheel angle Shitahe, actual steering wheel angle θhr and the output side in a state of touching the handle (hand ON) It shows an example waveform of the column angle .theta.c, until time t1 steer, time t1 ~ t2 is holding steering state, the time t2 ~ t3 is failback, time t3 later shows the steering holding state. Figure 13 shows a waveform example of each angle in a state where no touch the handle at the same time scale as FIG. 12 (hand OFF).
DESCRIPTION OF SYMBOLS
[0051]
1 handle (steering
wheel) 2 column shaft (steering wheel
shaft) 2A input column shaft
(IS) 2B output side column shaft
(OS) 20 Motor
23,201 torsion bar
100 control unit
120 input (IS / OS) difference angle generated part
130 hand ON / OFF determination unit
140 resonant filter
150 output (OS) the relative angle generating unit
200 torque sensor unit

WE CLAIM

Comprising a torsion bar to the column shaft connected to the handle, through a reduction gear mechanism, with drive control of the motor for applying the assist torque to a steering mechanism of a vehicle by the current command value, an electric with a function of switching the assist mode and automatic mode the power steering apparatus,
the torsion bar twist angle calculating unit for determining the angle twist the torsion bar on the basis of the torque information about the torsion bar,
output side for outputting the output side relative angle using a predetermined arithmetic expression from the electrical angle signal of the motor a column shaft relative angle generating unit,
and the actual steering wheel angle calculating unit for determining the actual steering wheel angle based on the torsion bar torsion angle and the output-side relative angle,
resonant filter determining an estimated steering wheel angle hands-off state from the output side relative angle When,
the actual steering wheel angle and the estimated hand of the hands-off state Deviation angle of angle, and hand ON / OFF determination unit determines hand ON when the time becomes a predetermined angle or more has continued for the predetermined period of time one or more
electric power steering apparatus characterized by comprising a.
[Requested item 2]
The hand ON / OFF determination unit, wherein after the determination of the hand ON, the deviation angle is an electric power steering control according to judges claim 1 hand OFF when the time the smaller than the predetermined angle continues for a predetermined time period 2 or more apparatus.
[Requested item 3]
Torque information on the torsion bar, the electric power steering control device according to claim 1 or 2 is a torsion torque about the column axis angle or the torsion bar about the handle.
[Requested item 4]
The torsion bar torsion angle calculation unit, the torsion type torque electric according to claim 3, wherein the torsion bar twist angle calculating unit for calculating the angle twist the torsion bar is divided by the spring constant of the torsion bar power steering control unit.
[Requested item 5]
The torsion bar torsion angle calculating unit inputs the torque sensor detection input column angle and torque sensor detection output column angle, the torsion bar torsion angle generator for generating the torsion bar torsion angle with the spring constant of the torsion bar the electric power steering apparatus according to claim 3 which is part.
[Requested item 6]
The output-side column shaft relative angle generator, the electrical angle signal later with the anti-rollover process, any of the predetermined arithmetic expression by the output-side claim is made as to output a relative angle 1 to 5 the electric power steering apparatus according to.
[Requested item 7]
Wherein the predetermined arithmetic expression is, the motor of the pole pairs in the electric angle signal, the electric power steering apparatus according to claim 6, wherein the arithmetic expression for multiplying the reduction ratio of the reduction mechanism.
[Requested item 8]
The resonance filter,
wherein the reproducing the resonance of the steering wheel, the estimated steering wheel angle is the actual steering wheel angle of the hand-release state obtained by inputting the output side column angle when steering from the output column axis actual wound When the electric power steering device according to any one of claims 1 to 7 has a characteristic that is substantially the same.
[Requested item 9]
The resonance filter, the electric power steering apparatus according to claim 8 which is a second or higher order LPF.