JP2021146919A - Power steering control device, power steering control method, program, and automatic steering system - Google Patents

Abstract

To perform steering by both steering by a driver and steering by an automatic steering system.SOLUTION: A power steering control device 100 comprises: an estimation part 140 which estimates a driver input torque that a driver of a vehicle gives to a steering wheel, on the basis of a steering torque applied to the steering wheel of the vehicle and a steering angle of the steering wheel; a hands-on detection part 150 which detects whether a current state is the hands-on state in which the driver is operating the steering wheel, on the basis of the estimated driver input torque; a target steering angle calculation part 160 which calculates a manual target steering angle corresponding to operation of the steering wheel by the driver, on the basis of the driver input torque; and a motor control part 180 which controls a motor of a power steering 20, on the basis of the detected state, which is a hands-on state, an automatic steering angle relating to automatic steering control of the vehicle, and the manual target steering angle.SELECTED DRAWING: Figure 2

Description

The present invention relates to a power steering control device, a power steering control method, a program, and an automatic steering system.

Conventionally, vehicles equipped with a power steering device and an automatic steering system are known. In an automatic steering system, it is known to determine whether or not the driver is in a hands-on state in operating the steering wheel (see, for example, Patent Document 1). Further, as a power steering device, a device for estimating an input torque when the driver is operating is known (see, for example, Patent Document 2).

JP-A-2017-114324 Japanese Unexamined Patent Publication No. 2002-154450

It is desirable that the automatic steering system enables steering by both the steering by the driver and the steering by the automatic steering system, depending on whether or not the driver applies force to the steering wheel.

Therefore, the present invention has been made in view of these points, and an object of the present invention is to enable steering by both steering by a driver and steering by an automatic steering system.

In the first aspect of the present invention, the power steering control device controls the power steering based on the automatic steering of the vehicle and the steering by the driver of the vehicle, and acquires the steering torque applied to the steering wheel of the vehicle. Based on the torque acquisition unit, the steering angle acquisition unit that acquires the steering angle of the steering wheel, the steering torque acquired by the torque acquisition unit, and the steering angle acquired by the steering angle acquisition unit. A hands-on state in which the driver is operating the steering wheel based on an estimation unit that estimates the driver input torque, which is the torque applied to the steering wheel by the driver, and the driver input torque estimated by the estimation unit. A target steering angle that calculates a manual target steering angle, which is a steering angle corresponding to the operation of the steering wheel by the driver, based on the hands-on detection unit that detects whether or not the steering wheel and the driver input torque estimated by the estimation unit. Based on the calculation unit, the detection state of the hands-on state by the hands-on detection unit, the automatic target steering angle related to the automatic steering control of the vehicle, and the manual target steering angle calculated by the target steering angle calculation unit. Provided is a power steering control device including a motor control unit for controlling the power steering motor.

The target steering angle calculation unit may calculate the manual target steering angle when the hands-on detection unit detects the hands-on state.

The motor control unit may control the motor based on a combined target steering angle obtained by combining the automatic target steering angle and the manual target steering angle.

The power steering control device further includes an abnormality detection unit that detects an abnormality of the driver, and the motor control unit includes the combined target steering angle when the abnormality detection unit detects an abnormality of the driver. The ratio of the manual target steering angle may be lower than the ratio of the manual target steering angle included in the combined target steering angle when the abnormality detecting unit does not detect the abnormality of the driver.

The power steering control device further includes an abnormality detection unit that detects an abnormality in the automatic steering control, and the motor control unit further includes the combined target steering angle when the abnormality detection unit detects an abnormality in the automatic steering control. The ratio of the automatic target steering angle included in is lower than the ratio of the automatic target steering angle included in the combined target steering angle when the abnormality detecting unit does not detect an abnormality in the automatic steering control. You may.

When the target steering angle calculation unit determines that the driver input torque estimated by the estimation unit is not good, the target steering angle calculation unit may calculate the manual target steering angle based on the steering torque acquired by the torque acquisition unit. good.

In the second aspect of the present invention, there are a step of acquiring the steering torque applied to the steering wheel of the vehicle, a step of acquiring the steering angle of the steering wheel, and the acquired steps, which are executed by a computer controlling the power steering. Based on the steering torque and the acquired steering angle, the step of estimating the driver input torque, which is the torque applied to the steering wheel by the driver of the vehicle, and the step of estimating the driver input torque based on the estimated driver input torque. A manual step that detects whether or not the driver is operating the steering wheel in a hands-on state, and a steering angle corresponding to the operation of the steering wheel by the driver based on the estimated driver input torque. The power steering is based on the step of calculating the target steering angle, the automatic target steering angle related to the automatic steering control of the vehicle when the hands-on state is detected, and the calculated manual target steering angle. Provided is a power steering control method having a step of controlling a motor of the power steering wheel.

In the third aspect of the present invention, there is provided a program that causes the computer to function as the power steering control device of the first aspect.

In the fourth aspect of the present invention, the vehicle has a steering wheel, a first detector for detecting the steering torque applied to the steering wheel, and a second detector for detecting the steering angle of the steering wheel. Provided is an automatic steering system including a power steering mounted on the vehicle and the power steering control device of the first aspect for controlling the power steering.

According to the present invention, there is an effect that steering can be performed by both steering by a driver and steering by an automatic steering system.

A configuration example of the automatic steering system 10 according to the present embodiment is shown. A configuration example of the power steering control device 100 according to the present embodiment is shown. The relationship between the automatic target steering angle, the manual target steering angle, and the steering angle of the steering wheel 21 is shown. The relationship between the automatic target steering angle, the manual target steering angle, and the steering angle of the steering wheel 21 when the abnormality detection unit 170 detects an abnormality of the driver is shown. An example of the operation flow of the power steering control device 100 according to the present embodiment is shown. An example of the operation flow of the weighting coefficient setting process according to this embodiment is shown.

<Configuration example of automatic steering system 10>
FIG. 1 shows a configuration example of the automatic steering system 10 according to the present embodiment. The automatic steering system 10 is, for example, a system mounted on a vehicle such as a passenger car or a truck. The automatic steering system 10 includes a vehicle power steering 20 and a power steering control device 100.

The power steering 20 assists the rotational operation of the steering wheel so that the driver can steer the steering wheel smoothly. This allows the driver to steer the steering wheel with less input torque. The power steering 20 includes a steering wheel 21, a motor 22, a worm 23, a worm wheel 24, a first torsion bar 25, a second torsion bar 26, an actuator 27, wheels 28, a first detector 31, and a second detector 32. Have.

The driver adjusts the traveling direction of the vehicle by operating the annular steering wheel 21. Here, the angle of the steering wheel 21 is defined as the steering angle. Further, the state in which the driver is operating the steering wheel 21 is set to the hands-on state, and the state in which the driver is not operating the steering wheel 21 is set to the hands-off state.

The motor 22 applies the assist torque to the steering wheel 21 by driving the steering wheel 21 in response to the input drive signal. The assist torque is a torque for reducing the steering force of the driver, and is a torque having the same sign as the driver input torque, which is the torque applied to the steering wheel 21 by the driver. The drive signal is, for example, a signal that specifies a current value to be passed through the motor 22. The motor 22 rotates the worm 23 and rotates the worm wheel 24 that meshes with the worm 23. One end of the shaft of the worm wheel 24 is connected to the steering wheel 21 via a first torsion bar 25.

The end of the worm wheel 24 opposite to one end of the shaft is connected to the actuator 27 via a second torsion bar 26. The actuator 27 changes the angle of the wheel 28 according to the force transmitted from the worm wheel 24. The actuator 27 is, for example, a hydraulic actuator.

The first detector 31 detects the steering torque applied to the steering wheel 21. The first detector 31 is provided on the first torsion bar 25, for example, and detects the restoring force of the first torsion bar 25 as steering torque.

The second detector 32 detects the steering angle of the steering wheel 21. The second detector 32 is provided on the steering wheel 21, for example, and detects an angle based on the steering angle of the steering wheel 21 that advances the vehicle straight as a steering angle. As an example, the reference angle is 0 degrees. Instead of this, the second detector 32 may be provided in the motor 22. In this case, the second detector 32 detects, for example, the angle at which the motor 22 rotates the worm 23, and outputs the angle of the steering wheel 21 corresponding to the detected angle as the steering angle.

The power steering control device 100 controls the power steering 20 as described above. The power steering control device 100 supplies the motor 22 with a drive signal for driving the motor 22 based on the automatic target steering angle related to the automatic steering control and the manual target steering angle related to the operation of the driver's steering wheel 21. .. The power steering control device 100 acquires, for example, an automatic target steering angle which is a steering angle related to the automatic steering control from an ECU (Engine Control Unit) or the like mounted on the vehicle for performing automatic steering control. The power steering control device 100 as described above will be described below.

<Configuration example of power steering control device 100>
FIG. 2 shows a configuration example of the power steering control device 100 according to the present embodiment. The power steering control device 100 includes a torque acquisition unit 110, a steering angle acquisition unit 120, a storage unit 130, an estimation unit 140, a hands-on detection unit 150, a target steering angle calculation unit 160, an abnormality detection unit 170, and the like. It includes a motor control unit 180.

The torque acquisition unit 110 acquires the steering torque applied to the steering wheel 21 of the vehicle from the power steering 20 of the vehicle. The torque acquisition unit 110 acquires steering torque from, for example, the first detector 31. Further, the torque acquisition unit 110 may acquire the steering torque detected by the first detector 31 and stored in the database or the like from the database. In this case, the torque acquisition unit 110 may acquire steering torque information via the network.

The steering angle acquisition unit 120 acquires the steering angle of the steering wheel 21 from the power steering 20. The steering angle acquisition unit 120 acquires the steering angle from, for example, the second detector 32. Further, the steering angle acquisition unit 120 may acquire the steering angle detected by the second detector 32 and stored in the database or the like from the database. In this case, the steering angle acquisition unit 120 may acquire information on the steering angle via the network.

The storage unit 130 stores information on the steering torque acquired by the torque acquisition unit 110 and the steering angle acquired by the steering angle acquisition unit 120. In addition, the storage unit 130 stores intermediate data, calculation results, threshold values, parameters, and the like generated (or used) by the power steering control device 100 in the process of operation. The storage unit 130 stores, for example, the values of the steering torque and the steering angle in association with the acquired time. Further, the storage unit 130 may store the steering torque and the steering angle values in association with the target steering angle. The storage unit 130 may supply the stored data to the request source in response to a request from each unit in the power steering control device 100.

When the computer operates as the power steering control device 100, the storage unit 130 may store information on the OS (Operating System) that functions as the power steering control device 100 and the program. Further, the storage unit 130 may store various information including a database referred to when the program is executed.

The storage unit 130 stores a torque assist map which is information relating the driver input torque, which is the torque given to the steering wheel 21 by the driver, and the assist torque given to the steering wheel 21 by the motor 22 with respect to the driver input torque. do. Further, the computer functions as the power steering control device 100 by executing the program stored in the storage unit 130.

The storage unit 130 includes, for example, a ROM (Read Only Memory) for storing a BIOS (Basic Input Output System) of a computer or the like, and a RAM (Random Access Memory) serving as a work area. Further, the storage unit 130 may include a large-capacity storage device such as an HDD (Hard Disk Drive) and / or an SSD (Solid State Drive). Further, the computer may further include a GPU (Graphics Processing Unit) and the like.

The estimation unit 140 estimates the driver input torque based on the steering torque acquired by the torque acquisition unit 110 and the steering angle acquired by the steering angle acquisition unit 120.

Specifically, the estimation unit 140 calculates an estimated value of the driver input torque by solving the equation of motion of the steering wheel 21 showing the relationship between the torque applied to the steering wheel 21 and the steering angle of the steering wheel 21. do. The equation of motion of the steering wheel 21 is shown as an example by the following equation.

Here, the driver input torque is T _d , the steering torque acquired by the torque acquisition unit 110 is _Th , the steering angle acquired by the steering angle acquisition unit 120 is θ _h , and the time is t. The first term on the left side of Eq. (Equation 1) is an inertial term, and I _h is used as the inertial coefficient. The second term on the left side of Eq. (Equation 1) is a viscosity term, and _Ch is a viscosity coefficient. A gravity term or the like may be further added to the left side of the equation (Equation 1).

The hands-on detection unit 150 detects whether or not the driver is in the hands-on state in which the steering wheel 21 is being operated, based on the driver input torque estimated by the estimation unit 140. The hands-on detection unit 150 detects that the driver is in the hands-on state, for example, when the estimated value of the driver input torque estimated by the estimation unit 140 exceeds the first threshold value. The hands-on detection unit 150 may detect that the driver input torque is in the hands-on state when the estimated value of the driver input torque exceeds the first threshold value continues for a predetermined time or longer. When the hands-on detection unit 150 detects that it is in the hands-on state, the hands-on detection unit 150 outputs the driver input torque estimated by the estimation unit 140 to the target steering angle calculation unit 160.

The target steering angle calculation unit 160 calculates a manual target steering angle, which is a steering angle corresponding to the operation of the steering wheel 21 by the driver, based on the driver input torque estimated by the estimation unit 140. The target steering angle calculation unit 160 calculates the manual target steering angle when the hands-on detection unit 150 detects the hands-on state.

Specifically, the target steering angle calculation unit 160 refers to the torque assist map stored in the storage unit 130, and identifies the assist torque associated with the driver input torque output from the hands-on detection unit 150. The target steering angle calculation unit 160 adds the specified assist torque to the driver input torque output from the hands-on detection unit 150 to calculate the combined torque.

The target steering angle calculation unit 160 may determine whether or not the estimation accuracy of the driver input torque of the hands-on detection unit 150 is good. In this case, the estimation unit 140 specifies the accuracy of the equation of motion of the steering wheel 21 described above in advance, and the target steering angle calculation unit 160 has good estimation accuracy of the driver input torque based on the accuracy of the equation of motion. Judge whether or not. Further, if the estimation delay of the driver input torque by the estimation unit 140 is large, the calculation of the correction value may be delayed with respect to the steering intention of the driver, and the steering feeling may deteriorate. Therefore, the target steering angle calculation unit 160 determines whether or not the steering feeling is deteriorated based on the response characteristics of the steering angle with respect to the manual target steering angle, so that the estimation accuracy of the driver input torque is good. It may be determined whether or not.

When the estimation accuracy of the driver input torque is not good, the target steering angle calculation unit 160 specifies the assist torque based on the steering torque acquired by the torque acquisition unit 110 instead of the driver input torque, and the assist torque is added to the steering torque. May be added to obtain the combined torque.

The target steering angle calculation unit 160 calculates the manual target steering angle by inputting the combined torque to the equation of motion of the steering wheel 21 and solving the equation of motion. The equation of motion of the steering wheel 21 when calculating the manual target steering angle is shown as an example as follows. Here, the combined torque is T _dc , and the manual target steering angle is θ _m . _Im , C _m , and K _m are parameters that the designer adjusts in advance so that the steering feeling is good. Incidentally, I _m and C _m has been assumed that the designer to adjust, not limited thereto, may be combined with I _h and C _h used in the equation of motion of the steering wheel 21.

The abnormality detection unit 170 detects an abnormality of the driver and an abnormality of the automatic steering control. For example, when the driver input torque estimated by the estimation unit 140 exceeds the second threshold value, or when the time displacement of the driver input torque estimated by the estimation unit 140 exceeds the third threshold value, the abnormality detection unit 170 of the driver Detect anomalies. Further, the abnormality detection unit 170 responds to the fact that the ECU performing the automatic steering control receives an automatic steering abnormality detection signal output when an abnormality of the sensor used for the automatic steering control or a clear lane deviation is detected. , Detects abnormalities in automatic steering control.

The abnormality detection unit 170 has detected an abnormality in the driver based on the driver input torque, but the present invention is not limited to this. For example, a driver abnormality may be detected in response to receiving a driver abnormality detection signal output when a driver abnormality is detected from a driver monitoring system (not shown).

The motor control unit 180 includes a hands-on state detected by the hands-on detection unit 150, a manual target steering angle output from the target steering angle calculation unit 160, and an automatic target steering angle output from an ECU or the like that performs automatic steering control. Controls the motor 22 of the power steering 20 based on the above.

The motor control unit 180 calculates a combined target steering angle that is a combination of an automatic target steering angle output from an ECU or the like that performs automatic steering control and a manual target steering angle calculated by the target steering angle calculation unit 160. The motor control unit 180 controls the motor 22 by generating a drive signal corresponding to the calculated combined target steering angle and supplying the drive signal to the motor 22. When the target steering angle calculation unit 160 does not calculate the manual target steering angle, the motor control unit 180 uses the automatic target steering angle output from the ECU or the like that performs the automatic steering control as the combined target steering angle as it is.

As an example, the motor control unit 180 calculates the combined target steering angle as shown in the following equation.
Here, the automatic target steering angle is θ _a , the combined target steering angle θ _ref , and the weighting coefficient are k. It is assumed that the minimum value of the weighting coefficient is 0 and the maximum value is 1.

When the hands-on detection unit 150 does not detect the hands-on state, the motor control unit 180 sets the weight coefficient k to 1 and controls the motor 22 based on the automatic target steering angle related to the automatic steering control. When the hands-on detection unit 150 detects the hands-on state, the motor control unit 180 sets the weighting coefficient k to 0 and controls the motor 22 based on the automatic target steering angle related to the automatic steering control. When the hands-on detection unit 150 does not detect the hands-on state, the motor control unit 180 sets the weighting coefficient k to a value larger than 0.5, gives priority to the automatic target steering angle, and controls the motor 22. You may. Further, when the hands-on detection unit 150 does not detect the hands-on state, the motor control unit 180 sets the weighting coefficient k to a value smaller than 0.5, gives priority to the manual target steering angle, and controls the motor 22. You may.

When the hands-on detection unit 150 detects the hands-on state while the hands-on detection unit 150 has not detected the hands-on state, the motor control unit 180 gradually changes the weighting coefficient from 1 to 0 according to the passage of time to achieve a synthesis target. Calculate the steering angle. For example, assuming that the period for switching the weighting coefficient from 1 to 0 is the first switching period, the motor control unit 180 changes the weighting coefficient from 1 to 0 by monotonically decreasing the weighting coefficient from 1 in the first switching period. Let me. For example, the first switching period is assumed to be 0.1 seconds, but the period is not limited to this and may be a period different from 0.1 seconds.

Further, when the hands-on detection unit 150 detects the hands-on state and the motor control unit 180 stops detecting the hands-on state, the motor control unit 180 gradually changes the weighting coefficient from 0 to 1 with the passage of time. To calculate the combined target steering angle. For example, assuming that the period for switching the weighting coefficient from 0 to 1 is the second switching period, the motor control unit 180 changes the weighting coefficient from 0 to 1 by monotonically increasing the weighting coefficient from 0 in the second switching period. Let me. For example, the second switching period is assumed to be 0.1 seconds, but the period is not limited to this and may be a period different from 0.1 seconds.

FIG. 3 shows the relationship between the automatic target steering angle, the manual target steering angle, and the steering angle of the steering wheel 21. In the example shown in FIG. 3, the broken line indicates the automatic target steering angle, the alternate long and short dash line indicates the manual target steering angle, and the solid line indicates the steering angle of the steering wheel 21. The horizontal axis represents time and the vertical axis represents angle.

As shown in FIG. 3, when the hands-on state is reached in the vicinity of 15 seconds, it can be confirmed that the steering angle of the steering wheel 21 follows the manual target steering angle. Further, when the hands-on state is changed to the hands-off state in the vicinity of 30 seconds, it can be confirmed that the steering angle of the steering wheel 21 follows the automatic target steering angle. By doing so, the motor control unit 180 can smoothly switch the steering based on whether or not it is in the hands-on state, and can maintain safe driving.

Further, in the motor control unit 180, when the abnormality detection unit 170 detects an abnormality in the automatic steering control, the abnormality detection unit 170 does not detect the driver's abnormality in the ratio of the automatic target steering angle included in the combined target steering angle. It is lower than the ratio of the automatic target steering angle included in the combined target steering angle in the case.

For example, when the abnormality detection unit 170 detects an abnormality in the automatic steering control while the hands-on detection unit 150 has not detected the hands-on state, the motor control unit 180 has a third switching period from the timing when the abnormality in the automatic steering control is detected. In, the weighting coefficient is changed from 1 to 0 by monotonically decreasing the weighting coefficient from 1. By doing so, the motor control unit 180 can switch to steering by the driver at an early stage when an abnormality is detected in the automatic steering control.

It should be noted that the driver may not always be able to immediately start steering when the hands-on detection unit 150 has not detected the hands-on state. Therefore, the third switching period may be longer than the first switching period.

Further, when the abnormality detection unit 170 detects the driver's abnormality, the motor control unit 180 determines the ratio of the manual target steering angle included in the combined target steering angle, and the abnormality detection unit 170 does not detect the driver's abnormality. It should be lower than the ratio of the manual target steering angle included in the combined target steering angle.

For example, when the abnormality detection unit 170 detects an abnormality in the driver, the motor control unit 180 sets the weighting coefficient to 1 or a value close to 1 regardless of whether or not the hands-on detection unit 150 detects the hands-on state.

FIG. 4 shows the relationship between the automatic target steering angle, the manual target steering angle, and the steering angle of the steering wheel 21 when the abnormality detection unit 170 detects the driver's abnormality. In the example shown in FIG. 4, similarly to FIG. 3, the broken line indicates the automatic target steering angle, the alternate long and short dash line indicates the manual target steering angle, and the solid line indicates the steering angle of the steering wheel 21. The horizontal axis represents time and the vertical axis represents angle. It is assumed that the scale on the horizontal axis shown in FIG. 3 is the same as the scale on the horizontal axis shown in FIG. Further, it is assumed that the scale of the vertical axis shown in FIG. 3 is the same as the scale of the vertical axis shown in FIG.

When the abnormality detection unit 170 detects an abnormality in the driver, the motor control by the automatic target steering angle is prioritized. Therefore, as shown in FIG. 4, even if the manual target steering angle changes in the vicinity of 15 seconds. It can be confirmed that the steering angle of the steering wheel 21 follows the automatic target steering angle. By doing so, the motor control unit 180 can maintain safe driving without reflecting the steering by the driver in the power steering when the driver's abnormality is detected.

<Processing flow in the power steering control device 100>
FIG. 5 shows an example of the operation flow of the power steering control device 100 according to the present embodiment. The power steering control device 100 controls the power steering 20 by executing the operations S300 to S380 of FIG. 5, and appropriately steers the steering wheel 21.

First, the motor control unit 180 acquires an automatic target steering angle (S300). The motor control unit 180 acquires, for example, an automatic target steering angle supplied from the ECU. Next, the torque acquisition unit 110 acquires the steering torque applied to the steering wheel 21 of the vehicle from the power steering 20 of the vehicle (S310). The torque acquisition unit 110 acquires the steering torque detection result from the first detector 31 provided in the power steering 20. Next, the steering angle acquisition unit 120 acquires the steering angle of the steering wheel 21 from the power steering 20 (S320). The steering angle acquisition unit 120 acquires the steering angle detection result from the second detector 32 provided in the power steering 20. It is desirable that the sampling timing and sampling time of the steering torque and the steering angle are substantially the same.

Next, the estimation unit 140 estimates the driver input torque based on the steering torque acquired by the torque acquisition unit 110 and the steering angle acquired by the steering angle acquisition unit 120 (S330). Next, the hands-on detection unit 150 detects whether or not the driver is in the hands-on state in which the steering wheel 21 is being operated, based on the driver input torque estimated by the estimation unit 140.

Next, the target steering angle calculation unit 160 executes the weighting coefficient setting process (S340). The details of the weighting coefficient setting process will be described later. Next, the target steering angle calculation unit 160 determines whether or not the hands-on detection unit 150 has detected the hands-on state (S350). When the target steering angle calculation unit 160 determines that the hands-on detection unit 150 has detected the hands-on state, the process is transferred to S360, and when it is determined that the hands-on state is not detected, the target steering angle calculation unit 160 shifts the process to S370.

Next, the target steering angle calculation unit 160 calculates a manual target steering angle, which is a steering angle corresponding to the operation of the steering wheel 21 by the driver, based on the driver input torque estimated by the estimation unit 140 (S360).

Next, the motor control unit 180 calculates a combined target steering angle that is a combination of the automatic target steering angle output from the ECU or the like that performs automatic steering control and the manual target steering angle calculated by the target steering angle calculation unit 160. (S370). Next, the motor control unit 180 controls the motor 22 (S380) by generating a drive signal corresponding to the combined target steering angle and supplying the drive signal to the motor 22, and returns to S300.

FIG. 6 shows an example of the operation flow of the weighting coefficient setting process according to the present embodiment.
First, the target steering angle calculation unit 160 determines whether or not the hands-on detection unit 150 has detected the hands-on state (S341). When the target steering angle calculation unit 160 determines that the hands-on detection unit 150 has detected the hands-on state, the process is transferred to S342, and when it is determined that the hands-on state is not detected, the target steering angle calculation unit 160 shifts the process to S344.

The target steering angle calculation unit 160 determines in S342 whether or not the weighting coefficient is larger than 0. When the target steering angle calculation unit 160 determines that the weighting coefficient is larger than 0 (YES in S342), the weighting coefficient is subtracted by a predetermined value (S343), and the weighting coefficient setting process ends. When the target steering angle calculation unit 160 determines that the weighting coefficient is 0 (NO in S342), the weighting coefficient setting process ends. The predetermined value is assumed to be a value smaller than 1, for example.

The target steering angle calculation unit 160 determines in S344 whether or not the weighting coefficient is smaller than 1. When the target steering angle calculation unit 160 determines that the weighting coefficient is smaller than 1 (YES in S344), the weighting coefficient is added by a predetermined value (S345), and the weighting coefficient setting process is terminated. When the target steering angle calculation unit 160 determines that the weighting coefficient is 1 (NO in S344), the weighting coefficient setting process ends.

[Effect of this embodiment]
As described above, the power steering control device 100 according to the present embodiment has a torque applied to the steering wheel 21 by the driver based on the steering torque applied to the steering wheel 21 of the vehicle and the steering angle of the steering wheel 21. A certain driver input torque is estimated, and based on the driver input torque, it is detected whether or not the driver is in the hands-on state of operating the steering wheel 21. The power steering control device 100 calculates a manual target steering angle, which is a steering angle corresponding to the operation of the steering wheel 21 by the driver, based on the driver input torque, and relates to a hands-on state detection state and automatic steering control of the vehicle. The motor 22 of the power steering 20 is controlled based on the automatic target steering angle and the calculated manual target steering angle. By doing so, the power steering control device 100 can be steered by both steering by the driver and steering by the automatic steering system.

Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments, and various modifications and changes can be made within the scope of the gist thereof. be. For example, in the power steering control device 100 of the embodiment, the steering wheel 21 and the wheel 28 are mechanically connected, but the present invention is not limited to this, and the steering wheel 21 and the wheel 28 are not mechanically connected. It may also be applied to a steering wheel type vehicle. In addition, all or part of the device can be functionally or physically distributed / integrated in any unit. Also included in the embodiments of the present invention are new embodiments resulting from any combination of the plurality of embodiments. The effect of the new embodiment produced by the combination also has the effect of the original embodiment.

10 Automatic steering system 20 Power steering 21 Steering wheel 22 Motor 23 Warm 24 Warm wheel 25 1st torsion bar 26 2nd torsion bar 27 Actuator 28 Wheel 31 1st detector 32 2nd detector 100 Power steering controller 110 Torque acquisition unit 120 Steering angle acquisition unit 130 Storage unit 140 Estimating unit 150 Hands-on detection unit 160 Target steering angle calculation unit 170 Abnormality detection unit 180 Motor control unit

Claims (9)

A power steering control device that controls power steering based on automatic steering of the vehicle and steering by the driver of the vehicle.
A torque acquisition unit that acquires the steering torque applied to the steering wheel of the vehicle, and
A steering angle acquisition unit that acquires the steering angle of the steering wheel, and a steering angle acquisition unit.
An estimation unit that estimates the driver input torque, which is the torque that the driver applies to the steering wheel, based on the steering torque acquired by the torque acquisition unit and the steering angle acquired by the steering angle acquisition unit.
Based on the driver input torque estimated by the estimation unit, a hands-on detection unit that detects whether or not the driver is in the hands-on state of operating the steering wheel, and
A target steering angle calculation unit that calculates a manual target steering angle, which is a steering angle corresponding to the operation of the steering wheel by the driver, based on the driver input torque estimated by the estimation unit.
The power steering of the power steering is based on the detection state of the hands-on state by the hands-on detection unit, the automatic target steering angle related to the automatic steering control of the vehicle, and the manual target steering angle calculated by the target steering angle calculation unit. The motor control unit that controls the motor and
A power steering control device. The target steering angle calculation unit calculates the manual target steering angle when the hands-on detection unit detects the hands-on state.
The power steering control device according to claim 1. The motor control unit controls the motor based on a combined target steering angle obtained by combining the automatic target steering angle and the manual target steering angle.
The power steering control device according to claim 1 or 2. Further having an abnormality detection unit for detecting an abnormality of the driver,
When the abnormality detecting unit detects an abnormality of the driver, the motor control unit does not detect the ratio of the manual target steering angle included in the combined target steering angle, and the abnormality detecting unit does not detect the abnormality of the driver. Lower than the ratio of the manual target steering angle included in the combined target steering angle in the case.
The power steering control device according to claim 3. Further having an abnormality detection unit for detecting an abnormality in the automatic steering control,
When the abnormality detection unit detects an abnormality in the automatic steering control, the motor control unit determines the ratio of the automatic target steering angle included in the combined target steering angle, and the abnormality detection unit detects the abnormality in the automatic steering control. It is lower than the ratio of the automatic target steering angle included in the combined target steering angle when it is not detected.
The power steering control device according to claim 3 or 4. When the target steering angle calculation unit determines that the driver input torque estimated by the estimation unit is not good, the target steering angle calculation unit calculates the manual target steering angle based on the steering torque acquired by the torque acquisition unit.
The power steering control device according to any one of claims 1 to 5. Performed by the computer that controls the power steering,
Steps to obtain the steering torque applied to the steering wheel of the vehicle,
The step of acquiring the steering angle of the steering wheel and
A step of estimating a driver input torque, which is a torque applied to the steering wheel by the driver of the vehicle, based on the acquired steering torque and the acquired steering angle.
Based on the estimated driver input torque, a step of detecting whether or not the driver is in the hands-on state of operating the steering wheel, and
A step of calculating a manual target steering angle, which is a steering angle corresponding to the operation of the steering wheel by the driver, based on the estimated driver input torque.
When the hands-on state is detected, a step of controlling the motor of the power steering based on the automatic target steering angle related to the automatic steering control of the vehicle and the calculated manual target steering angle.
A method of controlling power steering. A program that causes a computer to function as the power steering control device according to any one of claims 1 to 6. A power steering mounted on the vehicle, having a steering wheel of the vehicle, a first detector for detecting the steering torque applied to the steering wheel, and a second detector for detecting the steering angle of the steering wheel. When,
The power steering control device according to any one of claims 1 to 6, which controls the power steering.
Equipped with an automatic steering system.

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