A motion control device of a vehicle, a computer-readable medium storing a motion control program, and a motion control method of a vehicle

Abstract

The present application provides a motion control device of a vehicle, a computer readable medium storing a motion control program, and a motion control method of a vehicle. The motion control device includes: a required value acquisition unit that acquires a motion amount required value; a limit value setting unit that sets first to third motion amount limit values; a first command unit that sends a first motion amount command value based on the motion amount required value and the first motion amount limit value to a front wheel steering control unit; a second command unit that sends a second motion amount command value based on a first residual required value and the second motion amount limit value to a rear wheel steering control unit; and a third command unit that sends a command corresponding to a third motion amount command value based on a second residual required value and the third motion amount limit value to a drive control unit and a brake control unit.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a motion control device of a vehicle, a computer-readable medium storing a motion control program, and a motion control method of a vehicle. BACKGROUND

[0002] In Japanese Patent No. 4379793, the gist is described that if an instruction is input to a control unit of an electric power steering device from microcomputers of a plurality of instruction units, the control unit operates an actuator of the electric power steering device according to the instruction input from the microcomputers. The control unit of the electric power steering device determines whether an abnormality occurs in the microcomputers of the respective instruction units. Further, the control unit operates the actuator based on the instruction from the microcomputer determined not to have an abnormality. On the other hand, even if an instruction is input from the microcomputer determined to have an abnormality, the control unit does not operate the actuator according to the instruction.

[0003] A vehicle is provided with a plurality of actuators capable of generating a yaw moment to the vehicle. In such a vehicle, there is a case where a part of the plurality of actuators cannot normally operate. SUMMARY

[0004] In one embodiment of the present disclosure, a motion control device of a vehicle is provided. The vehicle includes a plurality of wheels including front wheels and rear wheels, a steering wheel, a front wheel steering shaft that operates in conjunction with rotation of the steering wheel, a front wheel steering actuator that adjusts a steering angle of the front wheels, a rear wheel steering actuator that adjusts a steering angle of the rear wheels, and a front-rear force adjustment actuator that adjusts a front-rear force of the plurality of wheels. The motion control device includes a required value acquisition section configured to acquire a motion amount required value that is a required value of a motion amount of the vehicle for turning, a limit value setting section configured to set a first motion amount limit value in accordance with a range in which the front wheel steering actuator can operate, set a second motion amount limit value in accordance with a range in which the rear wheel steering actuator can operate, and set a third motion amount limit value in accordance with a range in which the front-rear force adjustment actuator can operate, a first command section configured to derive a value corresponding to a smaller one of the motion amount required value and the first motion amount limit value as a first motion amount command value, and instruct operation of the front wheel steering actuator based on the first motion amount command value, a second command section configured to derive a value corresponding to a smaller one of a first remaining required value obtained by subtracting the first motion amount command value from the motion amount required value and the second motion amount limit value as a second motion amount command value, and instruct operation of the rear wheel steering actuator based on the second motion amount command value, and a third command section configured to derive a value corresponding to a smaller one of a second remaining required value obtained by subtracting the second motion amount command value from the first remaining required value and the third motion amount limit value as a third motion amount command value, and instruct operation of the front-rear force adjustment actuator based on the third motion amount command value.

[0005] In the above-described motion control device, the motion amount limit value can be set in accordance with the range in which the corresponding actuator can operate at the time. Therefore, the motion control device can set the first motion amount command value to a value that can be achieved by operation of the front wheel steering actuator. The motion control device can set the second motion amount command value to a value that can be achieved by operation of the rear wheel steering actuator. The motion control device can set the third motion amount command value to a value that can be achieved by operation of the front-rear force adjustment actuator. Furthermore, the motion control device can cause the vehicle to turn in accordance with the motion amount required value by instructing operation of the actuator based on such a command value, for example, to a control section for the actuator.

[0006] Therefore, even in a case where a part of the plurality of actuators cannot normally operate, the vehicle can be caused to turn.

[0007] In another aspect of the present disclosure, a computer-readable medium storing a motion control program executed by an execution device of a vehicle is provided. The vehicle includes a plurality of wheels including front wheels and rear wheels, a steering wheel, a front wheel steering shaft that operates in conjunction with rotation of the steering wheel, a front wheel steering actuator that adjusts a steering angle of the front wheels, a rear wheel steering actuator that adjusts a steering angle of the rear wheels, and a front-rear force adjustment actuator that adjusts a front-rear force of the plurality of wheels. The motion control program causes the execution device to execute: a required value derivation process that derives a motion amount required value that is a required value of a motion amount of the vehicle for turning the vehicle, a limit value setting process that sets a first motion amount limit value in accordance with a range in which the front wheel steering actuator can operate, sets a second motion amount limit value in accordance with a range in which the rear wheel steering actuator can operate, and sets a third motion amount limit value in accordance with a range in which the front-rear force adjustment actuator can operate, a first command value derivation process that derives a value corresponding to a smaller one of the motion amount required value and the first motion amount limit value as a first motion amount command value, a second command value derivation process that derives a value corresponding to a smaller one of a first remaining required value obtained by subtracting the first motion amount command value from the motion amount required value and the second motion amount limit value as a second motion amount command value, a third command value process that derives a value corresponding to a smaller one of a second remaining required value obtained by subtracting the second motion amount command value from the first remaining required value and the third motion amount limit value as a third motion amount command value, and an instruction process that instructs operation of the front wheel steering actuator based on the first motion amount command value, instructs operation of the rear wheel steering actuator based on the second motion amount command value, and instructs operation of the front-rear force adjustment actuator based on the third motion amount command value.

[0008] In another aspect of the disclosure, a vehicle motion control method is provided. The vehicle includes a plurality of wheels including front wheels and rear wheels, a steering wheel, a front wheel steering shaft that operates in conjunction with rotation of the steering wheel, a front wheel steering actuator that adjusts a steering angle of the front wheels, a rear wheel steering actuator that adjusts a steering angle of the rear wheels, and a front-rear force adjustment actuator that adjusts a front-rear force of the plurality of wheels. The vehicle motion control method includes deriving a motion amount demand value that is a demand value for a motion amount of the vehicle for turning, setting a first motion amount limit value in accordance with a range in which the front wheel steering actuator can operate, setting a second motion amount limit value in accordance with a range in which the rear wheel steering actuator can operate, setting a third motion amount limit value in accordance with a range in which the front-rear force adjustment actuator can operate, deriving a value corresponding to a smaller one of the motion amount demand value and the first motion amount limit value as a first motion amount command value, deriving a value corresponding to a smaller one of a first residual demand value and the second motion amount limit value as a second motion amount command value, wherein the first residual demand value is obtained by subtracting the first motion amount command value from the motion amount demand value, deriving a value corresponding to a smaller one of a second residual demand value and the third motion amount limit value as a third motion amount command value, wherein the second residual demand value is obtained by subtracting the second motion amount command value from the first residual demand value, instructing operation of the front wheel steering actuator based on the first motion amount command value, instructing operation of the rear wheel steering actuator based on the second motion amount command value, and instructing operation of the front-rear force adjustment actuator based on the third motion amount command value. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 is a schematic configuration diagram of a vehicle that represents a motion control device according to an embodiment.

[0010] Figure 2 is a control configuration block diagram of the vehicle that represents Figure 1 .

[0011] Figure 3 is a functional configuration block diagram of the motion control device that represents Figure 2 .

[0012] Figure 4 is a flowchart of a processing program executed by the motion control device that represents Figure 3 .

[0013] Figure 5 is a time chart that represents actions when the vehicle is caused to turn slowly.

[0014] Figure 6 is a time chart that represents actions when the vehicle is caused to make an emergency turn.

[0015] Figure 7 is a timing chart showing the operation when the vehicle is turned in a state where the abnormality occurs in the front wheel steering actuator.

[0016] Figure 8 is a timing chart showing the operation when the vehicle is turned in a state where the steering angle of the front wheel cannot be adjusted. DETAILED DESCRIPTION

[0017] Hereinafter, the motion control device according to Figures 1-8 An embodiment of the present disclosure will be described.

[0018] Figure 1 The schematic structure of the vehicle 10 to which the motion control device of the present embodiment is applied is illustrated.

[0019] <VEHICLE>

[0020] As shown in Figure 1 , the vehicle 10 is provided with a steering wheel 11, a front wheel steering shaft 12, a rear wheel steering shaft 15, and a plurality of wheels 18F, 18R. The plurality of wheels 18F, 18R include front wheels 18F and rear wheels 18R.

[0021] The steering wheel 11 is rotated by the operation of the driver of the vehicle 10. The front wheel steering shaft 12 is linearly moved in a direction corresponding to the direction of rotation of the steering wheel 11 out of two directions along the axis of the front wheel steering shaft 12. The front wheel 18F is linked to the front wheel steering shaft 12 via a steering tie rod 13. In the case where the front wheel steering shaft 12 is linearly moved, the front wheel 18F is steered in a direction corresponding to the direction of movement thereof.

[0022] The rear wheel steering shaft 15 is capable of linearly moving in two directions along the axis of the rear wheel steering shaft 15. The rear wheel 18R is linked to the rear wheel steering shaft 15 via a steering tie rod 16. In the case where the rear wheel steering shaft 15 is linearly moved, the rear wheel 18R is steered in a direction corresponding to the direction of movement of the rear wheel steering shaft 15.

[0023] As shown in Figure 1 and Figure 2 , the vehicle 10 is provided with a front wheel steering device 30, a rotation angle difference adjustment device 40, a steering wheel locking device 50, a rear wheel steering device 60, a driving device 70, and a braking device 80.

[0024] The front wheel steering device 30 has a front wheel steering actuator 31, and a front wheel steering control section 35 that controls the front wheel steering actuator 31. The front wheel steering control section 35 has, for example, an electronic control device. The front wheel steering actuator 31 has an electric motor 32 and a front wheel transmission mechanism 33. A drive shaft of the electric motor 32 is coupled to the front wheel steering shaft 12 via the front wheel transmission mechanism 33. The front wheel transmission mechanism 33 converts a rotational motion of the drive shaft of the electric motor 32 to a linear motion of the front wheel steering shaft 12. Therefore, by driving the electric motor 32 with the front wheel steering control section 35, the front wheel steering shaft 12 is linearly moved. In other words, the front wheel steering control section 35 adjusts the steering angle of the front wheel 18F by operating the front wheel steering actuator 31.

[0025] The rotation angle difference adjustment device 40 has a rotation angle adjustment actuator 41, and a rotation angle difference control section 45 that controls the rotation angle adjustment actuator 41. The rotation angle difference control section 45 has, for example, an electronic control device. The rotation angle adjustment actuator 41 has an input shaft 42 that rotates integrally with the steering wheel 11, and an output shaft 43 that rotates in synchronization with the linear motion of the front wheel steering shaft 12. The rotation angle adjustment actuator 41 operates in order to adjust a difference between a rotation angle of the input shaft 42 and a rotation angle of the output shaft 43, that is, a rotation angle difference Δθ. In a case where the operation of the rotation angle adjustment actuator 41 is stopped, the rotation angle difference Δθ is maintained.

[0026] A pinion gear tooth 43a is provided to the output shaft 43, and a rack gear tooth 12a that engages with the pinion gear tooth 43a is provided to the front wheel steering shaft 12. Therefore, the front wheel steering shaft 12 operates in synchronization with the rotation of the output shaft 43. In other words, the rotation angle difference control section 45 adjusts the steering angle of the front wheel 18F by changing the rotation angle difference Δθ by the operation of the rotation angle adjustment actuator 41 while maintaining the rotation angle of the input shaft 42.

[0027] The steering wheel locking device 50 has a steering wheel locking mechanism 51, and a lock control section 55 that controls the steering wheel locking mechanism 51. The lock control section 55 has, for example, an electronic control device. The steering wheel locking mechanism 51 selectively switches to a non-operational state that allows the rotation of the steering wheel 11, and an operational state that makes the steering wheel 11 unable to rotate. The state of the steering wheel locking mechanism 51 is switched from one of the non-operational state and the operational state to the other state by the control of the lock control section 55. If the rotation of the steering wheel 11 is restricted because the state of the steering wheel locking mechanism 51 becomes the operational state, the rotation angle of the input shaft 42 is maintained. Further, since the configuration of the steering wheel locking mechanism 51 is known, detailed description thereof is omitted.

[0028] The rear wheel steering device 60 has a rear wheel steering actuator 61 and a rear wheel steering control section 65 that controls the rear wheel steering actuator 61. The rear wheel steering control section 65 has, for example, an electronic control device. The rear wheel steering actuator 61 has an electric motor 62 and a rear wheel transmission mechanism 63. A drive shaft of the electric motor 62 is coupled to the rear wheel steering shaft 15 via the rear wheel transmission mechanism 63. The rear wheel transmission mechanism 63 converts a rotational motion of the drive shaft of the electric motor 62 to a linear motion of the rear wheel steering shaft 15. Thus, by driving the electric motor 62 with the rear wheel steering control section 65, the rear wheel steering shaft 15 is linearly moved. In other words, the rear wheel steering control section 65 adjusts the steering angle of the rear wheel 18R by operating the rear wheel steering actuator 61.

[0029] The drive device 70 has a travel motor 71 as a power source of the vehicle 10 and a drive control section 75 that controls the travel motor 71. The drive control section 75 has, for example, an electronic control device. In the example shown in the figure, the vehicle 10 is a front-wheel drive vehicle. In this case, the driving force output from the travel motor 71 is transmitted to the two front wheels 18F, and the driving force is not transmitted to the two rear wheels 18R. Figure 1

[0030] The brake device 80 has a brake actuator 81 and a brake control section 85 that controls the brake actuator 81. The brake control section 85 has, for example, an electronic control device. The brake actuator 81 is configured to be able to independently adjust the braking force applied to the plurality of wheels 18F, 18R. Since the configuration of the brake actuator 81 is known, detailed description thereof is omitted.

[0031] In the following description, the force that adjusts the front-rear acceleration of the vehicle 10 is referred to as "front-rear force". In the case where the vehicle 10 is accelerated, the front-rear force is a positive value. On the other hand, in the case where the vehicle 10 is decelerated, the front-rear force is a negative value. The driving force transmitted to the wheels by the power source of the vehicle 10 and the braking force applied to the wheels by the operation of the brake actuator 81 correspond to the front-rear force. Thus, the brake actuator 81 and the travel motor 71 correspond to a "front-rear force adjustment actuator" that adjusts the front-rear force of the plurality of wheels 18F, 18R.

[0032] <Detection system of vehicle>

[0033] ​The detection system of vehicle 10 includes multiple types of sensors that detect vehicle state quantities representing the state of vehicle 10. For example, vehicle 10 includes a vehicle speed sensor 91, a front and rear acceleration sensor 92, a lateral acceleration sensor 93, a yaw rate sensor 94, an output shaft sensor 95, and a steering angle sensor 96 as such sensors. The vehicle speed sensor 91 detects the vehicle speed V. The front and rear acceleration sensor 92 detects the front and rear acceleration Gx of vehicle 10. The lateral acceleration sensor 93 detects the lateral acceleration Gy of vehicle 10. The yaw rate sensor 94 detects the yaw rate Yr of vehicle 10. The output shaft sensor 95 detects the rotation angle θu of the output shaft 43. The steering angle sensor 96 detects the steering angle θh of the steering wheel 11.

[0034] The detection system of vehicle 10 includes a monitoring device 100 that monitors the surroundings of vehicle 10. The monitoring device 100 includes a camera 101, a radar 102, and a GPS receiver 103. The camera 101 captures images of the surroundings of vehicle 10. The radar 102 detects the distance between vehicle 10 and other vehicles, the distance from vehicle 10 to obstacles, and the distance from vehicle 10 to pedestrians. The GPS receiver 103 acquires the position of vehicle 10.

[0035] <Vehicle Control System>

[0036] like Figure 2 As shown, the control system of vehicle 10 includes a driving support device 120 and a motion control device 130 according to this embodiment.

[0037] <<Driver Support Device>>

[0038] The driving assistance device 120 is an electronic control device. For example, the driving assistance device 120 has a CPU and a memory. In this case, the memory stores a control program executed by the CPU.

[0039] By executing a control program via the CPU, the driving support device 120 functions as a multi-type application request unit. The application request unit is a functional unit that implements driving support functions to support the driver's operation of the vehicle 10. The application request unit sends the request values ​​for implementing the driving support functions to the motion control device 130.

[0040] The driving support function includes a function of causing the vehicle 10 to automatically turn. As the driving support function of causing the vehicle 10 to automatically turn, for example, a lane keeping assist and an automatic driving can be cited. In a case where the application request section requests the turning of the vehicle 10, the request value outputted by the application request section includes a request value XR of a state quantity of the vehicle 10 indicating a turning state of the vehicle 10. The state quantity of the vehicle 10 indicating the turning state of the vehicle 10 is, for example, a yaw rate or a lateral acceleration. The request value XR of such a state quantity is a request value of the yaw rate or a request value of the lateral acceleration. Hereinafter, the request value XR of the state quantity of the vehicle 10 indicating the turning state of the vehicle 10 will be referred to as a "turning state quantity request value XR".

[0041] The driving support device 120 derives the motion quantity request value MR based on the information inputted from the monitoring device 100 in a case where the vehicle 10 is caused to automatically turn, and transmits the derived motion quantity request value MR to the motion control device 130.

[0042] <<Motion control device>>

[0043] The motion control device 130 communicates with other control devices mounted on the vehicle, i.e., the driving support device 120, the front wheel steering control section 35, the rotation angle difference control section 45, the lock control section 55, the rear wheel steering control section 65, the drive control section 75, and the brake control section 85.

[0044] The motion control device 130 inputs various information from the monitoring device 100 and detection signals of various sensors 91 to 96. Also, the motion control device 130 instructs the operation of the plurality of actuators based on the turning state quantity request value XR transmitted from the driving support device 120, the information inputted from the monitoring device 100, the detection signals of the various sensors 91 to 96, and the information obtained from the above-described plurality of control sections (control circuits) 35, 45, 55, 65, 75, 85.

[0045] The motion control device 130 is provided with a processing circuit 131. The processing circuit 131 has a CPU 132 and a memory 133. A plurality of control programs are stored in the memory 133. One of the plurality of control programs is a motion control program for causing the actuators related to the turning of the vehicle 10 to operate to cause the vehicle 10 to turn. The CPU 132 executes these control programs. In this regard, the CPU 132 corresponds to an "execution device".

[0046] As Figure 3As shown, the CPU 132 functions as the required value acquisition section Ml l, the abnormality determination section M13, the availability derivation section M15, and the limit value setting section M17 by executing the control program stored in the memory 133. In addition, the CPU 132 functions as the first instruction section M19, the second instruction section M21, and the third instruction section M23.

[0047] The required value acquisition section Ml l acquires a required value of a motion amount of the vehicle 10 for turning the vehicle 10, that is, a motion amount required value MR, based on the turning state amount required value XR transmitted by the driving support device 120. The motion amount of the vehicle 10 for turning the vehicle 10 is, for example, a yaw moment. In the present embodiment, the required value acquisition section Ml l acquires the motion amount required value MR based on an operation value derived by feedback control using a deviation of the motion amount required value MR from the yaw rate Yr as an input, and the turning state amount required value XR, in the case where the turning state amount required value XR is the yaw rate. The required value acquisition section Ml l acquires the motion amount required value MR based on an operation value derived by feedback control using a deviation of the turning state amount required value XR from the lateral acceleration Gy as an input, and the turning state amount required value XR, in the case where the turning state amount required value XR is the lateral acceleration.

[0048] The abnormality determination section M13 determines whether or not each of the plurality of actuators described above is abnormal. The abnormality determination section M13 determines that the actuator is abnormal in a case where it receives information indicating that the actuator is abnormal from the control section for the actuator. For example, the abnormality determination section M13 determines that the front wheel steering actuator 31 is abnormal in a case where it receives information indicating that the front wheel steering actuator 31 is abnormal from the front wheel steering control section 35.

[0049] In addition, the abnormality determination section M13 can determine that the actuator corresponding to the control section is abnormal in a case where it cannot communicate with the control section. For example, the abnormality determination section M13 can determine that the front wheel steering actuator 31 is abnormal in a case where it cannot communicate with the front wheel steering control section 35.

[0050] In this way, the abnormality determination section M13 grasps the state of the front wheel steering actuator 31, the state of the rear wheel steering actuator 61, the state of the rotation angle adjustment actuator 41, the state of the steering wheel lock mechanism 51, the state of the travel motor 71, and the state of the brake actuator 81. The "state of the actuator" referred to here means "whether or not the actuator is abnormal".

[0051] The availability deriving section M15 derives a range in which the front-wheel steering actuator 31 can operate as the availability MA3 of the front-wheel steering actuator 31. The availability deriving section M15 derives a range in which the rotation angle adjustment actuator 41 can operate as the availability MA4 of the rotation angle adjustment actuator 41. The availability deriving section M15 derives a range in which the rear-wheel steering actuator 61 can operate as the availability MA6 of the rear-wheel steering actuator 61. The availability deriving section M15 derives a range in which the fore-aft force adjustment actuator can operate as the availability MA7 of the fore-aft force adjustment actuator.

[0052] The availability deriving section M15 derives the availability of the actuator on the basis of a design value of an upper limit of the amount of work of the actuator, the current state of work of the actuator, and the determination result of the abnormality determination section M13. The state of work of the actuator includes at least the amount of work of the actuator, the rate of change of the amount of work, and the acceleration of change of the amount of work. The availability deriving section M15 estimates the amount of work that can be reached after a prescribed time, that is, the predicted value of the amount of work, on the basis of the current state of work of the actuator. The availability deriving section M15 selects the smaller one of the estimated predicted value of the amount of work and the design value of the upper limit of the amount of work of the actuator. Further, the greater the selected value, the greater the value that the availability deriving section M15 derives as the availability. However, in the case where it is determined that the actuator has generated an abnormality, the availability deriving section M15 derives zero as the availability of the actuator. In this way, the availability deriving section M15 derives the availability MA3 of the front-wheel steering actuator 31, the availability MA4 of the rotation angle adjustment actuator 41, and the availability MA6 of the rear-wheel steering actuator 61.

[0053] Further, the availability deriving section M15 derives the availability MA4 of the rotation angle adjustment actuator 41 also taking into account whether the steering wheel lock mechanism 51 has generated an abnormality. That is, the availability deriving section M15 derives zero as the availability MA4 even if it is determined that the rotation angle adjustment actuator 41 has not generated an abnormality in the case where it is determined that the steering wheel lock mechanism 51 has generated an abnormality. This is because the steering angle of the front wheel 18F does not change even if the rotation angle is changed by the operation of the rotation angle adjustment actuator 41 in the case where the rotation angle of the input shaft 42 cannot be maintained.

[0054] In the present embodiment, the travel motor 71 and the brake actuator 81 correspond to the fore-aft force adjustment actuator as described above. Therefore, the availability deriving section M15 derives the availability of the travel motor 71 and the availability of the brake actuator 81, and derives the availability MA7 of the fore-aft force adjustment actuator on the basis of them. At this time, the availability deriving section M15 derives zero as the availability MA7 in the case where the abnormality determination section M13 determines that at least one of the travel motor 71 and the brake actuator 81 has generated an abnormality.

[0055] The limit value setting portion M17 sets the first motion amount limit value ML3 in accordance with the availability MA3 of the front wheel steering actuator 31. The first motion amount refers to the above-described motion amount (in the present embodiment, the yaw moment) that can be achieved by the operation of the front wheel steering actuator 31. Therefore, the first motion amount limit value ML3 becomes an upper limit of the first motion amount at this time that can be estimated in accordance with the availability MA3. The greater the availability MA3, the greater value the limit value setting portion M17 sets as the first motion amount limit value ML3. At this time, the limit value setting portion M17 can set the first motion amount limit value ML3 also in consideration of the vehicle speed V.

[0056] The limit value setting portion M17 sets the second motion amount limit value ML6 in accordance with the availability MA6 of the rear wheel steering actuator 61. The second motion amount refers to the above-described motion amount that can be achieved by the operation of the rear wheel steering actuator 61. Therefore, the second motion amount limit value ML6 becomes an upper limit of the second motion amount at this time that can be estimated in accordance with the availability MA6. The greater the availability MA6, the greater value the limit value setting portion M17 sets as the second motion amount limit value ML6. At this time, the limit value setting portion M17 can set the second motion amount limit value ML6 also in consideration of the vehicle speed V.

[0057] The limit value setting portion M17 sets the third motion amount limit value ML7 in accordance with the availability MA7 of the front-rear force adjustment actuator. The third motion amount refers to the above-described motion amount that can be achieved by the operation of the front-rear force adjustment actuator, i.e., the travel motor 71 and the brake actuator 81. Therefore, the third motion amount limit value ML7 becomes an upper limit of the third motion amount at this time that can be estimated in accordance with the availability MA7. The greater the availability MA7, the greater value the limit value setting portion M17 sets as the third motion amount limit value ML7. At this time, the limit value setting portion M17 can set the third motion amount limit value ML7 also in consideration of the vehicle speed V.

[0058] The limit value setting portion M17 sets the fourth motion amount limit value ML4 in accordance with the availability MA4 of the rotation angle adjustment actuator 41. The fourth motion amount refers to the above-described motion amount that can be achieved by the operation of the rotation angle adjustment actuator 41. Therefore, the fourth motion amount limit value ML4 becomes an upper limit of the fourth motion amount at this time that can be estimated in accordance with the availability MA4. The greater the availability MA4, the greater value the limit value setting portion M17 sets as the fourth motion amount limit value ML4. At this time, the limit value setting portion M17 can set the fourth motion amount limit value ML4 also in consideration of the vehicle speed V.

[0059] Further, in the present embodiment, the limit value setting portion M17 does not set the fourth movement amount limit value ML4 in a case where it is determined that the front wheel steering actuator 31 does not have an abnormality. On the other hand, the limit value setting portion M17 sets the fourth movement amount limit value ML4 in a case where it is determined that the front wheel steering actuator 31 has an abnormality. This is because the rotation angle adjustment actuator 41 is not operated in a case where the front wheel steering actuator 31 does not have an abnormality and the steering angle of the front wheel 18F can be adjusted by the front wheel steering actuator 31.

[0060] Further, the limit value setting portion M17 sets zero as the movement amount limit value for the actuator determined to have an abnormality. For example, in a case where it is determined that the front wheel steering actuator 31 has an abnormality, the limit value setting portion M17 sets zero as the first movement amount limit value ML3. Further, for example, in a case where it is determined that the rear wheel steering actuator 61 has an abnormality, the limit value setting portion M17 sets zero as the second movement amount limit value ML6.

[0061] The first command portion M19 derives the first movement amount command value MC3. That is, the first command portion M19 derives a value corresponding to the value of the smaller one of the movement amount required value MR and the first movement amount limit value ML3 as the first movement amount command value MC3 in a case where it is determined that the front wheel steering actuator 31 does not have an abnormality. For example, the first command portion M19 derives the value of the smaller one of the movement amount required value MR and the first movement amount limit value ML3 as the first movement amount command value MC3. Then, the first command portion M19 instructs the operation of the front wheel steering actuator 31 based on the first movement amount command value MC3. That is, the first command portion M19 transmits the first movement amount command value MC3 to the front wheel steering control portion 35. In this way, the first command portion M19 causes the front wheel steering actuator 31 to perform the operation based on the first movement amount command value MC3.

[0062] On the other hand, the first command section M19 derives, as the first movement amount command value MC3, a value corresponding to the smaller one of the movement amount request value MR and the fourth movement amount limit value ML4, in a case where it is determined that the front wheel steering actuator 31 has generated an abnormality. For example, the first command section M19 derives, as the first movement amount command value MC3, a value of the smaller one of the movement amount request value MR and the fourth movement amount limit value ML4. Then, the first command section M19 instructs the operation of the rotation angle adjustment actuator 41 based on the first movement amount command value MC3, and instructs the state of the steering wheel lock mechanism 51 to be the active state. That is, the first command section M19 transmits the first movement amount command value MC3 to the rotation angle difference control section 45, and transmits, to the lock control section 55, an instruction of the gist of making the state of the steering wheel lock mechanism 51 the active state. In this way, the first command section M19 causes the rotation angle adjustment actuator 41 to operate based on the first movement amount command value MC3, and sets the state of the steering wheel lock mechanism 51 to the active state.

[0063] Further, there is a case where both the front wheel steering actuator 31 and the rotation angle adjustment actuator 41 have generated an abnormality. In this case, the vehicle 10 is turned by the operation of the rear wheel steering actuator 61 and the fore-aft force adjustment actuator. In a case like this where the steering angle of the front wheel 18F cannot be adjusted, the first command section M19 can transmit, to the lock control section 55, an instruction of the gist of making the state of the steering wheel lock mechanism 51 the active state. In other words, the first command section M19 sets the state of the steering wheel lock mechanism 51 to the active state.

[0064] The second command section M21 derives, as the second movement amount command value MC6, a value corresponding to the smaller one of a first residual request value MR1 obtained by subtracting the first movement amount command value MC3 from the movement amount request value MR and the second movement amount limit value ML6. For example, the second command section M21 derives, as the second movement amount command value MC6, a value of the smaller one of the first residual request value MR1 and the second movement amount limit value ML6. Then, the second command section M21 instructs the operation of the rear wheel steering actuator 61 based on the second movement amount command value MC6. That is, the second command section M21 transmits the second movement amount command value MC6 to the rear wheel steering control section 65. In this way, the second command section M21 causes the rear wheel steering actuator 61 to operate based on the second movement amount command value MC6.

[0065] The third command section M23 derives a value corresponding to the smaller one of the second residual request value MR2 obtained by subtracting the second movement amount command value MC6 from the first residual request value MR1 and the third movement amount limit value ML7 as the third movement amount command value MC7. For example, the third command section M23 derives the value of the smaller one of the second residual request value MR2 and the third movement amount limit value ML7 as the third movement amount command value MC7. Then, the third command section M23 instructs the operation of the fore-aft force adjustment actuator based on the third movement amount command value MC7. That is, the third command section M23 sends a command corresponding to the third movement amount command value MC7 to the control section (or control circuit) for the fore-aft force adjustment actuator, that is, the drive control section 75 and the brake control section 85. In this way, the third command section M23 causes the fore-aft force adjustment actuator to operate based on the third movement amount command value MC7.

[0066] <Turning control of vehicle>

[0067] Referring to Figure 4 A processing program executed by the CPU 132 when causing the vehicle 10 to automatically turn will be described. The processing program shown in FIG. 12 is executed by the CPU 132 executing a movement control program at every prescribed control cycle. Figure 4

[0068] In this processing program, in step Sll, the CPU 132 acquires a movement amount request value MR by functioning as a request value acquisition section Ml l. That is, the CPU 132 acquires a value derived based on the latest value of the turning state amount request value XR transmitted by the driving support device 120 and the latest value of the detection value of the sensor as the movement amount request value MR. In the present embodiment, step Sll corresponds to the "request value derivation processing".

[0069] In step S13, the CPU 132 determines whether or not each actuator is abnormal by functioning as an abnormality determination section M13. This processing of step S13 is referred to as "abnormality determination processing".

[0070] In step S15, the CPU 132 derives the availability MA3 of the front wheel steering actuator 31, the availability MA6 of the rear wheel steering actuator 61, and the availability MA7 of the fore-aft force adjustment actuator by functioning as an availability derivation section Ml 5. In addition, the CPU 132 derives the availability MA4 of the rotation angle adjustment actuator 41. This processing of step S15 is referred to as "availability derivation processing".

[0071] ​In step S17, the CPU 132 functions as a limit value setting section Ml 7 to set the first movement amount limit value ML3, the second movement amount limit value ML6, the third movement amount limit value ML7, and the fourth movement amount limit value ML4. However, in a case where it is determined that no abnormality has occurred in the front wheel steering actuator 31, the CPU 132 does not set the fourth movement amount limit value ML4. In this case, the CPU 132 sets zero as the fourth movement amount limit value ML4. In the present embodiment, step S17 corresponds to the "limit value setting processing".

[0072] In step S19, the CPU 132 functions as a first instruction section Ml 9 to derive the first movement amount instruction value MC3. In a case where it is determined that no abnormality has occurred in the front wheel steering actuator 31, the CPU 132 derives the first movement amount instruction value MC3 as the instruction value for the front wheel steering actuator 31. In a case where it is determined that an abnormality has occurred in the front wheel steering actuator 31 and it is determined that no abnormality has occurred in the rotation angle adjustment actuator 41 and the steering wheel lock mechanism 51, the CPU 132 derives the first movement amount instruction value MC3 as the instruction value for the rotation angle adjustment actuator 41. In the present embodiment, step S19 corresponds to the "first instruction value derivation processing".

[0073] In step S21, the CPU 132 functions as a second instruction section M21 to derive the second movement amount instruction value MC6 as the instruction value for the rear wheel steering actuator 61. At this time, in a case where the first movement amount instruction value MC3 is equal to the movement amount demand value MR, the CPU 132 derives zero as the second movement amount instruction value MC6. In the present embodiment, step S21 corresponds to the "second instruction value derivation processing".

[0074] In step S23, the CPU 132 functions as a third instruction section M23 to derive the third movement amount instruction value MC7 as the instruction value for the front-rear force adjustment actuator. At this time, in a case where the sum of the first movement amount instruction value MC3 and the second movement amount instruction value MC6 is equal to the movement amount demand value MR, the CPU 132 derives zero as the third movement amount instruction value MC7. In the present embodiment, step S23 corresponds to the "third instruction value derivation processing".

[0075] In step S25, CPU 132 instructs the actuators to operate. Specifically, if it is determined that the front wheel steering actuator 31 is not malfunctioning, CPU 132, acting as a first command unit M19, instructs the front wheel steering control unit 35 to operate the front wheel steering actuator 31 based on a first motion command value MC3. If it is determined that the front wheel steering actuator 31 is malfunctioning, CPU 132, acting as a first command unit M19, instructs the rotation angle difference control unit 45 to operate the rotation angle adjustment actuator 41 based on the first motion command value MC3, and instructs the locking control unit 55 to activate the steering wheel locking mechanism 51. Furthermore, CPU 132, acting as a second command unit M21, instructs the rear wheel steering control unit 65 to operate the rear wheel steering actuator 61 based on a second motion command value MC6. Furthermore, the CPU 132 functions as the third instruction unit M23 to instruct the drive control unit 75 and the brake control unit 85 to operate the driving motor 71 and the brake actuator 81, which correspond to the third motion command value MC7. In this embodiment, step S25 corresponds to "instruction processing". Then, the CPU 132 temporarily terminates this processing procedure.

[0076] <Function and Effects of This Implementation Method>

[0077] Reference Figure 5 , Figure 6 , Figure 7 as well as Figure 8 The function and effect of making the vehicle turn 10 degrees are explained.

[0078] (A1) Figure 5 The example shown illustrates this.

[0079] This example illustrates a scenario where no abnormality occurs in any of the multiple actuators involved in turning, and the vehicle 10 turns slowly. Figure 5 The thick solid lines in (A) and (E) represent the shift in the required exercise value MR.

[0080] In this example, such as Figure 5 As shown in (A), the first motion limit value ML3 is not lower than the motion requirement value MR. Therefore, a value identical to the motion requirement value MR is derived as the first motion command value MC3. Furthermore, if the first motion command value MC3 is sent from the motion control device 130 to the front wheel steering control unit 35, the front wheel steering control unit 35 activates the front wheel steering actuator 31 based on the first motion command value MC3. Through the operation of the front wheel steering actuator 31 in this way, as... Figure 5As shown in (E), the actual motion of vehicle 10, i.e., the actual motion value MRp, progresses in the same manner as the motion requirement value MR. The motion requirement value MR is the value corresponding to the turning state quantity requirement value XR derived from the driving support device 120. Therefore, by operating the front wheel steering actuator 31, turning of vehicle 10 according to the requirements of the driving support device 120 can be achieved.

[0081] Furthermore, in this example, no abnormality occurred in the front wheel steering actuator 31. Therefore, as Figure 5 As shown in (B), zero is set as the limit value for the rotation angle adjustment actuator 41, which is also the fourth motion limit value ML4. Furthermore, since the vehicle 10 can be turned according to the requirements of the driving support device 120 by adjusting the steering angle of the front wheels 18F, therefore... Figure 5 As shown in (C) and (D), zero is derived as the indication value for the rear wheel steering actuator 61, i.e., the second motion command value MC6, and the indication value for the front and rear force adjustment actuator, i.e., the third motion command value MC7, respectively.

[0082] (A2) Figure 6 The example shown illustrates this.

[0083] This example illustrates a situation where none of the multiple actuators involved in the turn-related process exhibited any abnormality, yet the vehicle was forced into an emergency turn. In this case, such as... Figure 6 As shown by the thick solid lines in (A) and (E), the rate of increase of the required exercise value MR is relatively large.

[0084] In this example, no abnormality occurred in the front wheel steering actuator 31. Therefore, as Figure 6 As shown in (A) and (B), the motion control device 130 sends the first motion command value MC3 to the front wheel steering control unit 35, but does not send the first motion command value MC3 to the rotation angle difference control unit 45. Therefore, the steering angle of the front wheel 18F is adjusted by the front wheel steering actuator 31.

[0085] In addition, such as Figure 6 As shown in (A), during the period from time t11 to time t12, the first motion limit value ML3 is lower than the motion requirement value MR. In this case, the same value as the first motion limit value ML3 is derived as the first motion command value MC3. That is, during this period, the first motion command value MC3 is lower than the motion requirement value MR. Therefore, by adjusting the steering angle of the front wheels 18F solely through the front wheel steering actuator 31, the turning of the vehicle 10 as required by the driving support device 120 cannot be achieved.

[0086] In the present embodiment, a value obtained by subtracting the first movement amount limit value ML3 from the movement amount demand value MR is derived as the first residual demand value MR1. As described above, during the period from the time tll to the time tl2, the first movement amount limit value ML3 is lower than the movement amount demand value MR, so a value different from zero is derived as the first residual demand value MR1 as shown in (B) and (C) of FIG. 12. In this way, during this period, a value of the smaller one of the first residual demand value MR1 and the second movement amount limit value ML6 is derived as the second movement amount command value MC6. Then, the second movement amount command value MC6 is transmitted from the movement control device 130 to the rear wheel steering control section 65, so the rear wheel steering control section 65 operates the rear wheel steering actuator 61 based on the second movement amount command value MC6. That is, the steering angle of the rear wheel 18R is adjusted in accordance with the second movement amount command value MC6. Figure 6

[0087] In the present example, the turning of the vehicle 10 in accordance with the movement amount demand value MR cannot be achieved only by the operation of the front wheel steering actuator 31 and the rear wheel steering actuator 61. That is, as shown in (C) of FIG. 13, the second movement amount command value MC6 is lower than the first residual demand value MR1, so a value different from zero is derived as the second residual demand value MR2 as shown in (D) of FIG. 13. That is, a value obtained by subtracting the second movement amount command value MC6 from the first residual demand value MR1 is derived as the second residual demand value MR2. In this way, during this period, a value of the smaller one of the second residual demand value MR2 and the third movement amount limit value ML7 is derived as the third movement amount command value MC7. Then, a command corresponding to the third movement amount command value MC7 is transmitted from the movement control device 130 to the drive control section 75 and the brake control section 85. Therefore, based on this command, the drive control section 75 operates the travel motor 71, and the brake control section 85 operates the brake actuator 81. That is, the difference in the front-rear force between the front wheel on the inside of the turn and the front wheel on the outside of the turn in the front wheel 18F is adjusted. Figure 6 Figure 6

[0088] During the period in which the first movement amount limit value ML3 is lower than the movement amount demand value MR, adjustment of the steering angle of the rear wheel 18R by the rear wheel steering actuator 61 or adjustment of the difference in the front-rear force of the front wheels 18F by the front-rear force adjustment actuator is performed in addition to adjustment of the steering angle of the front wheel 18F by the front wheel steering actuator 31. Thereby, even in the case where a sharp turn is requested from the drive assist device 120 in the automatic travel of the vehicle 10, it is possible to make the running situation of the vehicle 10 close to the request of the drive assist device 120 as shown in (E) of FIG. 14. Figure 6

[0089] ​​​​Furthermore, after time t12, the first motion limit value ML3 is higher than the motion requirement value MR. Therefore, zero is derived as the second motion command value MC6 and the third motion command value MC7, respectively. As a result, the vehicle 10 can turn according to the requirements of the driving support device 120 by adjusting the steering angle of the front wheels 18F through the front wheel steering actuator 31.

[0090] (A3) Figure 7 The example shown illustrates this.

[0091] In this example, the driver assistance device 120 requests that the vehicle 10 turn slowly, but an anomaly occurs in the front wheel steering actuator 31. On the other hand, among the multiple actuators related to turning, the actuators other than the front wheel steering actuator 31 do not produce an anomaly.

[0092] In this example, such as Figure 7 As shown in (A), due to an anomaly occurring in the front wheel steering actuator 31, zero is set as the first motion limit value ML3. On the other hand, as... Figure 7 As shown in (B), a fourth motion limit value ML4 is set. Furthermore, the fourth motion limit value ML4 is not lower than the motion requirement value MR. Therefore, a value identical to the motion requirement value MR is derived as the first motion command value MC3. Then, the motion control device 130 sends a command to the locking control unit 55 to activate the steering wheel locking mechanism 51, and sends the first motion command value MC3 to the rotation angle difference control unit 45. In this way, the locking control unit 55 activates the steering wheel locking mechanism 51, thus limiting the rotation of the steering wheel 11. That is, maintaining the rotation angle of the input shaft 42. In this state, the rotation angle difference control unit 45 activates the rotation angle adjustment actuator 41 based on the first motion command value MC3. In this way, the rotation angle difference Δθ is made to correspond to the first motion command value MC3 by the rotation angle adjustment actuator 41. That is, the steering angle of the front wheel 18F is adjusted by the rotation angle adjustment actuator 41. Thus, as... Figure 7 As shown in (E), the actual motion value MRp is shifted in the same manner as the required motion value MR. Therefore, in this example, the vehicle 10 can be turned according to the requirements of the driving support device 120 by adjusting the operation of the actuator 41 by rotating the angle. That is, the vehicle 10 can be turned even if the front wheel steering actuator 31, one of the multiple actuators related to turning, cannot operate normally.

[0093] In this example, the vehicle 10 can be turned according to the requirements of the driving support device 120 by adjusting the steering angle of the front wheels 18F, so as Figure 7As shown in (C) and (D), the indicator value for the rear wheel steering actuator 61, i.e., the second motion command value MC6, and the indicator value for the front and rear force adjustment actuator, i.e., the third motion command value MC7, are both set to zero.

[0094] Furthermore, there are cases where the vehicle 10 cannot be turned as required by the driving support device 120 by operating the rotation angle adjustment actuator 41 alone. In this case, in addition to the rotation angle adjustment actuator 41, the rear wheel steering actuator 61 and the front-rear force adjustment actuator are also operated. At this time, among the rear wheel steering actuator 61 and the front-rear force adjustment actuator, the rear wheel steering actuator 61 is operated first.

[0095] (A4) Figure 8 The example shown illustrates this.

[0096] In this example, the driver assistance device 120 requests that the vehicle 10 turn slowly, but an anomaly occurs in either the front wheel steering actuator 31 or the rotation angle adjustment actuator 41. That is, the front wheels 18F cannot be steered. On the other hand, no anomaly occurs in the rear wheel steering actuator 61 or the front-rear force adjustment actuator.

[0097] In this case, such as Figure 8 As shown in (A) and (B), zero is set as the first motion limit value ML3 and the fourth motion limit value ML4, respectively. Therefore, zero is derived as the first motion command value MC3. Furthermore, a command is sent from the motion control device 130 to the steering wheel locking mechanism 51 to make the state of the steering wheel locking mechanism 51 active. Moreover, if the state of the steering wheel locking mechanism 51 is active, the rotation angle of the steering wheel 11 and the input shaft 42 is maintained.

[0098] The value obtained by subtracting the first exercise limit value ML3 from the exercise requirement value MR is derived as the first remaining requirement value MR1. In this example, the value that is the same as the exercise requirement value MR is derived as the first remaining requirement value MR1. Additionally, as... Figure 8 As shown in (C), the second motion limit value ML6 is not lower than the first remaining requirement value MR1. Therefore, the first remaining requirement value MR1 is set as the second motion command value MC6. The second motion command value MC6 is sent from the motion control device 130 to the rear wheel steering control unit 65, so the rear wheel steering control unit 65 operates the rear wheel steering actuator 61 based on the second motion command value MC6. That is, the steering angle of the rear wheel 18R is adjusted according to the second motion command value MC6. Furthermore, by adjusting the steering angle of the rear wheel 18R in this way, the rotation of the steering wheel 11, i.e., the steering of the front wheel 18F, is restricted, so the vehicle 10 can be easily turned. As a result, by adjusting the steering angle of the rear wheel 18R, as Figure 8The actual value MRp of the motion amount (E) in the above equation is moved in the same manner as the required value MR of the motion amount. Therefore, in this example, turning of the vehicle 10 in accordance with the requirement of the driving support device 120 can be achieved by the operation of the rear wheel steering actuator 61. That is, even in the case where the front wheel steering actuator 31 and the rotation angle adjustment actuator 41, which are related to turning, cannot normally operate, the vehicle 10 can be turned.

[0099] Further, there is a case where turning of the vehicle 10 in accordance with the requirement of the driving support device 120 cannot be achieved by the operation of the rear wheel steering actuator 61 alone. In this case, the front-rear force adjustment actuator is also operated in addition to the rear wheel steering actuator 61.

[0100] Here, a case where the front-rear force adjustment actuator is preferentially operated instead of the rear wheel steering actuator 61 is considered in the case where the actuator 31, 41 that adjusts the steering angle of the front wheel 18F has an abnormality. In this case, by increasing the braking force applied to the front wheel on the inside of the turn among the left and right front wheels 18F, a front-rear force difference is generated in the left and right front wheels 18F, so the vehicle 10 can generate a yaw moment. However, as a whole of the vehicle 10, the braking force is increased, and the vehicle 10 decelerates. In order to suppress such deceleration of the vehicle 10, although it is possible to suppress the deceleration of the vehicle 10 caused by the generation of the front-rear force difference in the left and right front wheels 18F by increasing the driving force of the travel motor 71, the energy efficiency of the vehicle 10 deteriorates.

[0101] In view of this, in the present embodiment, the rear wheel steering actuator 61 is preferentially operated compared to the front-rear force adjustment actuator. Thereby, even in the case where the steering angle of the front wheel 18F cannot be adjusted, or turning of the vehicle 10 in accordance with the requirement from the motion control device 130 cannot be achieved by the adjustment of the steering angle of the front wheel 18F alone, turning of the vehicle 10 in accordance with the requirement can be achieved while suppressing the decrease in the energy efficiency of the vehicle 10.

[0102] <Modification Example>

[0103] The above embodiment can be modified as follows. The above embodiment and the following modification example can be implemented in combination with each other within a range where there is no technical contradiction.

[0104] • In the above embodiment, when deriving the availability of the actuator, the availability is derived taking into account the determination result of whether the actuator has an abnormality, but it is not limited thereto. That is, the availability of the actuator can also be derived without taking into account the determination result of whether the actuator has an abnormality. However, in this case, when setting the motion amount limit value of the actuator, it is sufficient to take into account the determination result of whether the actuator has an abnormality. That is, it is sufficient to set zero as the motion amount limit value for the actuator determined to have an abnormality.

[0105] • Zero can also not be set as the movement amount limit value for the actuator determined to have generated an abnormality. In this case, the movement control device 130 can only instruct the operation of the actuator determined to have generated an abnormality to the control section of the actuator.

[0106] • The movement control device 130 can also be applied to a vehicle that does not have the rotation angle difference adjustment device 40. In this case, when the front wheel steering actuator 31 is determined to have generated an abnormality, the operation of the rear wheel steering actuator 61 is instructed. Also, in a case where the turning of the vehicle according to the movement amount demand value MR cannot be achieved by only the operation of the rear wheel steering actuator 61, the operation of the front-rear force adjustment actuator is also instructed.

[0107] • The fourth movement amount limit value ML4 for the rotation angle adjustment actuator 41 can also be derived even in a case where the rotation angle adjustment actuator 41 is determined not to have generated an abnormality.

[0108] • In the above-described embodiment, zero is set as the movement amount limit value for the actuator determined to have generated an abnormality, but this is not limiting. That is, there can be a case where the operation state value indicating the operation state of the actuator is able to be acquired even in a case where the actuator has generated an abnormality. The case where the operation state value of the actuator that has generated an abnormality is able to be acquired can be considered to be a case where the turning moment is generated by the operation of the actuator. Therefore, in a case where the operation state value of the actuator is able to be acquired even in a case where an abnormality has occurred, a value corresponding to the current value of the operation state value can also be set as the movement amount limit value. The value corresponding to the operation state value refers to a value obtained by converting the operation state value into a movement amount. However, even in this case, zero is set as the movement amount limit value in a case where the operation state value of the actuator that has generated an abnormality is not able to be acquired.

[0109] • A value obtained by subtracting a prescribed correction amount from the value of the smaller one of the movement amount demand value MR and the first movement amount limit value ML3 can also be derived as the first movement amount command value MC3. In this case, a value corresponding to the smaller one of the movement amount demand value MR and the first movement amount limit value ML3 can also be derived as the first movement amount command value MC3.

[0110] • A value obtained by subtracting a prescribed correction amount from the value of the smaller one of the first residual demand value MR1 and the second movement amount limit value ML6 can also be derived as the second movement amount command value MC6. In this case, a value corresponding to the smaller one of the first residual demand value MR1 and the second movement amount limit value ML6 can also be derived as the second movement amount command value MC6.

[0111] • The value obtained by subtracting a prescribed correction amount from the value of the smaller one of the second residual request value MR2 and the third movement amount limit value ML7 can also be derived as the third movement amount command value MC7. In this case, the value corresponding to the smaller one of the second residual request value MR2 and the third movement amount limit value ML7 can also be derived as the third movement amount command value MC7.

[0112] • In the above-described embodiment, in the case where the vehicle 10 is turned in a state where the steering angle of the front wheel 18F cannot be adjusted, the lock control section 55 is instructed to make the state of the steering wheel lock mechanism 51 the active state, but is not limited thereto. That is, in the case where the vehicle 10 is turned in a state where the steering angle of the front wheel 18F cannot be adjusted, the state of the steering wheel lock mechanism 51 can not be switched from the inactive state to the active state.

[0113] • The drive device can have an engine as a power source of the vehicle in addition to the travel motor 71. In addition, the drive device can be configured not to have the travel motor 71 as long as it has an engine as a power source of the vehicle. In this case, the engine also corresponds to the front-rear force adjustment actuator.

[0114] • The drive device can be configured to have a drive motor for each of the plurality of wheels 18F, 18R. In this case, the vehicle can be made to generate a yaw moment by adjusting the difference in driving force between the right and left wheels.

[0115] • The vehicle can be a rear-wheel drive vehicle or an all-wheel drive vehicle.

[0116] • The processing circuit 131 of the movement control device 130 is not limited to having a CPU and a ROM and performing software processing. That is, the processing circuit 131 can have any one of the following (a) to (c).

[0117] (a) The processing circuit 131 has one or more processors that perform various processes according to a computer program. The processor includes a CPU, and a memory such as a RAM and a ROM. The memory stores program codes or instructions that cause the CPU to perform processes. The memory, which is a computer-readable medium, includes all available media that a computer can access, which is general or specific to a computer.

[0118] (b) The processing circuitry 131 has one or more dedicated hardware circuits that perform various processes. As the dedicated hardware circuit, for example, an Application Specific Integrated Circuit (ASIC) or an FPGA (Field Programmable Gate Array) can be cited. In addition, ASIC is an abbreviation for "Application Specific Integrated Circuit". FPGA is an abbreviation for "Field Programmable Gate Array".

[0119] (c) The processing circuitry 131 has a processor that performs a part of various processes according to a computer program, and a dedicated hardware circuit that performs the remaining processes in the various processes.

Claims

1. A motion control device for a vehicle, wherein, The vehicle described above includes: multiple wheels, including front and rear wheels; a steering wheel; a front wheel steering axle that operates in conjunction with the rotation of the steering wheel; a front wheel steering actuator for adjusting the steering angle of the front wheels; a rear wheel steering actuator for adjusting the steering angle of the rear wheels; and a front-rear force adjustment actuator for adjusting the front-rear force of the multiple wheels. The aforementioned motion control device includes: The requirement value acquisition unit is configured to acquire a motion quantity requirement value, which is a motion quantity requirement value of the vehicle used to turn the aforementioned vehicle. The limit setting unit is configured to set a first motion limit value based on the operating range of the front wheel steering actuator, set a second motion limit value based on the operating range of the rear wheel steering actuator, and set a third motion limit value based on the operating range of the front and rear force adjustment actuator. The first instruction unit is configured to derive a value corresponding to the smaller of the above-mentioned motion quantity requirement value and the above-mentioned first motion quantity limit value as a first motion quantity instruction value, and instruct the operation of the above-mentioned front wheel steering actuator based on the first motion quantity instruction value. The second command unit is configured to derive a value corresponding to the smaller of the first remaining required value and the second motion limit value as a second motion limit command value, and to instruct the operation of the rear wheel steering actuator based on the second motion limit command value, wherein the first remaining required value is obtained by subtracting the first motion limit command value from the motion limit value; and The third instruction unit is configured to derive a value corresponding to the smaller of the second remaining requirement value and the third motion amount limit value as a third motion amount instruction value, and instruct the operation of the fore-and-aft force adjustment actuator based on the third motion amount instruction value, wherein the second remaining requirement value is obtained by subtracting the second motion amount instruction value from the first remaining requirement value.

2. The vehicle motion control device according to claim 1, wherein, The above-mentioned vehicles have the following features: The steering wheel locking mechanism is configured to selectively switch between a non-operating state that allows the steering wheel to rotate and an operating state that prevents the steering wheel from rotating; and The rotation angle adjustment actuator is configured to have an input shaft that rotates integrally with the steering wheel and an output shaft that rotates synchronously with the operation of the front wheel steering shaft. It operates to adjust the difference between the rotation angle of the input shaft and the rotation angle of the output shaft. The aforementioned limit setting unit is configured to set a fourth motion amount limit value based on the operating range of the aforementioned rotation angle adjustment actuator. The first instruction unit is configured to, in the event of an abnormality in the front wheel steering actuator, derive a value corresponding to the smaller of the required motion value and the fourth motion limit value as the first motion instruction value, instruct the operation of the rotation angle adjustment actuator based on the first motion instruction value, and instruct the steering wheel locking mechanism to be in the aforementioned operating state.

3. The vehicle motion control device according to claim 2, wherein, The first instruction unit is configured to instruct the steering wheel locking mechanism to enter the aforementioned working state when the vehicle is turning because the steering angle of the front wheels cannot be adjusted.

4. The vehicle motion control device according to any one of claims 1 to 3, wherein, The aforementioned limit setting unit is configured to set zero as the motion limit value for the aforementioned actuator that generates abnormalities.

5. The vehicle motion control device according to any one of claims 1 to 3, wherein, The aforementioned limit setting unit is configured such that, when an operating state value representing the operating state of the actuator can be obtained even if an abnormality occurs, a value corresponding to the current value of the operating state of the actuator is set as the motion amount limit value for the actuator that has caused the abnormality; and when the operating state value of the actuator cannot be obtained, zero is set as the motion amount limit value for the actuator that has caused the abnormality.

6. A computer-readable medium storing a motion control program executed by an actuator of a vehicle, wherein, The vehicle described above includes: multiple wheels, including front wheels and rear wheels; a steering wheel; a front wheel steering axle that operates in conjunction with the rotation of the steering wheel; and a front wheel steering actuator that adjusts the steering angle of the front wheels. The rear wheel steering actuator adjusts the steering angle of the rear wheels; and the front-rear force adjustment actuator adjusts the front-rear force of the multiple wheels. The above motion control program causes the above actuator to perform: The required value is exported to export the required motion value, which is the required motion value of the vehicle used to make the above-mentioned vehicle turn. The limit value setting process sets a first motion limit value based on the working range of the front wheel steering actuator, sets a second motion limit value based on the working range of the rear wheel steering actuator, and sets a third motion limit value based on the working range of the front and rear force adjustment actuator. The first instruction value export process exports the value corresponding to the smaller of the above-mentioned exercise volume requirement value and the above-mentioned first exercise volume limit value, as the first exercise volume instruction value. The second instruction value export process exports the value corresponding to the smaller of the first remaining requirement value and the second exercise volume limit value as the second exercise volume instruction value, wherein the first remaining requirement value is obtained by subtracting the first exercise volume instruction value from the exercise volume requirement value. The third instruction value processing derives a value corresponding to the smaller of the second remaining requirement value and the aforementioned third exercise volume limit value as the third exercise volume instruction value, wherein the aforementioned second remaining requirement value is obtained by subtracting the aforementioned second exercise volume instruction value from the aforementioned first remaining requirement value; and The instruction process instructs the operation of the front wheel steering actuator based on the first motion command value, instructs the operation of the rear wheel steering actuator based on the second motion command value, and instructs the operation of the front and rear force adjustment actuator based on the third motion command value.

7. A method for controlling the motion of a vehicle, wherein, The vehicle described above includes: multiple wheels, including front and rear wheels; a steering wheel; a front wheel steering axle that operates in conjunction with the rotation of the steering wheel; a front wheel steering actuator for adjusting the steering angle of the front wheels; a rear wheel steering actuator for adjusting the steering angle of the rear wheels; and a front-rear force adjustment actuator for adjusting the front-rear force of the multiple wheels. The above motion control methods include: Derive the required motion value, which is the required motion value of the vehicle used to make the above vehicle turn; A first motion limit value is set according to the operating range of the aforementioned front wheel steering actuator; A second motion limit value is set according to the operating range of the aforementioned rear wheel steering actuator; A third motion limit value is set based on the range in which the aforementioned front and rear force adjustment actuator can operate; The value corresponding to the smaller of the above-mentioned exercise volume requirement value and the above-mentioned first exercise volume limit value is derived as the first exercise volume instruction value; The value corresponding to the smaller of the first remaining requirement value and the second exercise volume limit value is derived as the second exercise volume instruction value, wherein the first remaining requirement value is obtained by subtracting the first exercise volume instruction value from the exercise volume requirement value. The value corresponding to the smaller of the second remaining requirement value and the third exercise volume limit value is derived as the third exercise volume instruction value. The second remaining requirement value is obtained by subtracting the second exercise volume instruction value from the first remaining requirement value. Instructs the operation of the front wheel steering actuator based on the aforementioned first motion command value; Instructs the operation of the rear wheel steering actuator based on the aforementioned second motion command value; as well as The operation of the aforementioned forward and backward force adjustment actuator is indicated based on the aforementioned third motion quantity command value.

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