JP6523720B2 - Rear wheel steering control system - Google Patents

Description

  The present invention relates to a rear wheel steering control device mounted on a vehicle such as a car.

2. Description of the Related Art A rear wheel steering apparatus that steers a rear wheel in addition to front wheel steering is conventionally known for the purpose of achieving stable traveling performance of a vehicle. The control device of the rear wheel steering system incorporates a microcomputer, determines the control amount of the steering angle and the toe angle accurately from the values of various sensors for constantly monitoring the state of the vehicle, for steering. The actuator is being driven. The rear wheel steering system is an important function that determines the traveling performance of the vehicle, and estimates the optimal steering angle according to the state of the vehicle and the condition of the road surface, and implements vehicle stabilization control.
Therefore, when an abnormality occurs in the system, it is desirable to reliably detect the abnormality and maintain the safety performance as much as possible.

  The following techniques have been proposed as measures to prevent the behavior of the vehicle from becoming unstable at the time of an abnormality caused by a system related to a control device that steers the left and right of the rear wheels independently. For example, there is a rear wheel steered vehicle provided with a vehicle behavior stabilization control system in order to prevent a decrease in vehicle running stability when the rear wheel steer system is abnormal. In this vehicle, an abnormality in rear wheel steering control (impossible to change toe angle, undetectable, etc.) occurs, and particularly in the toe-out state, the abnormality is detected and the vehicle behavior stabilization control system is turned on. In order to stabilize the

Patent No. 5320286 gazette

  In Patent Document 1, control is performed to stabilize the vehicle only when an abnormality occurs on the system side. For example, when an abnormality occurs in a toe-out state, unstable behavior can be avoided. However, the vehicle behavior stability is greatly reduced compared to the normal time.

  An object of the present invention is that, in a rear wheel steering control device that steers left and right rear wheels of a vehicle independently of each other, steering control can not be performed on either the left or right due to an abnormality in an electronic control device that controls an actuator. It is an object of the present invention to provide a rear wheel steering control device that prevents the behavior of the vehicle from becoming unstable.

The rear wheel steering control device of the premise configuration is a rear wheel steering control device 13 that controls the rear wheel steering device 12 capable of controlling the steering angles and toe angles of the rear wheels 10 and 11 of the vehicle, respectively.
The rear wheel steering apparatus 12 includes a pair of actuators 14L and 14R that steer the left and right rear wheels 10 and 11 independently, and the actuators 14L and 14R include steering motors 25L and 25R and the steering An absolute position detector 27L capable of detecting an absolute position of an output portion of a rotation angle detector 26L, 26R for detecting a rotation angle of the motor 25L, 25R and an actuator 14L, 14R driven by the steering motor 25L, 25R. , 27R, and
The rear wheel steering control device 13 has a pair of electronic control devices 13L and 13R that respectively control the pair of actuators 14L and 14R, and the steering motor 25L that respectively configures the pair of actuators 14L and 14R, 25R, rotation angle detectors 26L and 26R, absolute position detectors 27L and 27R, and a connection switching unit 31 which alternately switches the connection between the pair of electronic control devices 13L and 13R;
An abnormality determination unit 32 that detects that an abnormality that prevents the normal operation of the actuators 14L and 14R has occurred in one of the pair of electronic control devices 13L and 13R;
When the abnormality determination unit 32 detects that the abnormality has occurred in one of the electronic control devices 13L and 13R, the actuator 14L normally connected to the electronic control devices 13L and 13R in which the abnormality is detected. , 14R, switching operation to the connection switching unit 31 so that the steering motors 25L, 25R, rotation angle detectors 26L, 26R, and absolute position detectors 27L, 27R are connected to the other electronic control devices 13L, 13R. And an abnormality handling control unit 33 for performing the process.

  According to this configuration, when one of the left and right becomes incapable of turning control due to the abnormality of the electronic control devices 13L and 13R that control the actuators 14L and 14R, the other electronic control devices 13L and 13R and the left and right actuators 14L , 14R to be connected. Therefore, the steering control can be performed also for the actuators 14L and 14R incapable of turning control, and the behavior of the vehicle can be prevented from becoming unstable.

Before SL abnormality handling control unit 33, the abnormality determining unit 32 or the electronic control device 13L by, when the abnormality is detected to have occurred 13R, command of the switching operation to the connection switching section 31 and wherein each of the actuators 14L, an instruction turning to 14R, intends rows according to the rules defined.
If the other electronic control devices 13L, 13R and the left and right actuators 14L, 14R are simply switched to be connected when an abnormality occurs, the left and right rear wheels 10, 11 will perform the same steering operation. By giving a prescribed steering command when switching the connection, appropriate steering of the rear wheels 10 and 11 can be performed, and the behavior of the vehicle may become unstable. This can be prevented better.

For reference Proposed Example, before Symbol abnormality handling control unit 33, the abnormality determining unit 32 or the electronic control device 13L by, when the abnormality is detected to have occurred in the 13R, to the connection switching section 31 A predetermined switching operation command may be issued, and a command may be issued to drive the actuators 14L and 14R on both sides back to the neutral position of turning.
When one of the left and right sides becomes incapable of turning control due to an abnormality in any of the electronic control devices 13L, 13R, the other electronic control devices 13L, 13R and the left and right actuators 14L, 14R are connected When switched, the steering control can be performed also for the actuators 14L and 14R that can not be steered, but because the time connected with the electronic control devices 13L and 13R is limited, sufficient rear wheel steering control can not be performed. There is a case. If the left and right actuators 14L and 14R are steered to the neutral position, free rear wheel steering can not be performed, but unstable behavior of the vehicle can be prevented safely.
In this specification, “a command of a predetermined switching operation” may be a command of a switching operation defined arbitrarily, for example, it may be switched alternately every fixed time, and switching is performed temporarily, After that, the original connection state may be restored.

In the rear wheel steering control device according to the first aspect of the present invention, in the premise configuration, the abnormality handling control unit 33 causes the abnormality determination unit 32 to cause the abnormality in any one of the electronic control devices 13L and 13R. when it is detected, the command and the actuators 14L switching operation to the connection switching section 31, a command for turning to 14R, and performs according to the rules defined, pre Symbol abnormality handling control unit 33 gives a command to cause the connection switching unit 31 to perform a predetermined switching operation when the abnormality determination unit 32 detects that any of the electronic control devices 13L and 13R has occurred. The rear wheels 10 and 11 on the inner ring side of the turning travel of the vehicle are fixed at the neutral position, and a command to drive so as to steer only the rear wheels 10 and 11 on the outer ring side For example Ru.
Thus, in the case where only the rear wheels 10 and 11 on the outer ring side are steered while the rear wheels 10 and 11 on the inner ring side are fixed at the neutral position, the behavior of the vehicle is well prevented from becoming unstable. Under the condition that an abnormality occurs in one of the electronic control devices 13L and 13R, it is possible to leave the function of rear wheel steering as much as possible. In particular, by steering the rear wheel outer ring side, the vehicle behavior stability can be improved as compared to the case where the rear wheel is in the neutral position. Thus, the behavior of the vehicle can be prevented from becoming unstable, and the stability of the vehicle behavior can be further enhanced.

In the rear wheel steering control device according to a second aspect of the present invention, in the premise configuration, the abnormality handling control unit 33 causes the abnormality determination unit 32 to cause the abnormality in any one of the electronic control devices 13L and 13R. when it is detected, the command and the actuators 14L switching operation to the connection switching section 31, a command for turning to 14R, and performs according to the rules defined, pre Symbol abnormality handling control unit When the abnormality determination unit 32 detects that the abnormality has occurred in any one of the electronic control devices 13L and 13R, the connection switching unit 31 initially detects an abnormality when the abnormality is detected by the actuators 14L and 14R. The inner wheel side is gradually moved to the neutral position while switching the connection with the electronic control devices 13L, 13R at predetermined time intervals, and at the same time, outside the turning travel. It intends row control to move the rear wheels becomes the side to a predetermined angle.
As described above, while the connection between the actuators 14L and 14R and the electronic control devices 13L and 13R is switched every predetermined time, the inner ring side is gradually moved to the neutral position, and at the same time, the outer ring side is controlled to move to the predetermined angle. Also in the case where the behavior of the vehicle is prevented from becoming unstable, it is possible to leave the function of rear wheel steering as safely as possible under the condition that an abnormality has occurred in one of the electronic control devices 13L, 13R. Also in this case, particularly, by turning the rear wheel outer wheel side, the vehicle behavior stability can be enhanced as compared with the case where the rear wheel is in the neutral position. Thus, the behavior of the vehicle can be prevented from becoming unstable, and the stability of the vehicle behavior can be further enhanced.

Wheel steering control system after the first invention in this inventions is a wheel steering control device after that controls the wheel turning device after capable of controlling the steering angle and the toe angle of the rear wheels of the vehicle, the rear rotary The rudder device includes a pair of actuators for independently steering the left and right rear wheels independently, and each of the actuators includes a steering motor, a rotation angle detector for detecting a rotation angle of the steering motor, and the turning. And an absolute position detector capable of detecting an absolute position of an output portion of an actuator driven by a rudder motor, and the rear wheel steering control device has a pair of electronic control devices for controlling the pair of actuators. And a connection switching unit that alternately switches between the steering motor, the rotation angle detector, the absolute position detector, and the pair of electronic control devices, which respectively configure the pair of actuators, and the pair of electronic components An abnormality determination unit that detects that an abnormality that can not drive the actuator normally occurs in any one electronic control device of the control devices, and the abnormality in any one of the electronic control devices by the abnormality determination unit Is detected, the steering motor, the rotation angle detector, and the absolute position detector in the actuator normally connected to the electronic control unit where the abnormality is detected are connected to the other electronic control unit the abnormality handling control unit and Bei give a to perform the switching operation in the connection switching unit so as to be, the abnormality handling control unit, that said abnormality has occurred in any of the electronic control device by the abnormality determining unit When it is detected, the command of the switching operation to the connection switching unit and the command of steering to each of the actuators are performed according to a defined rule The abnormality handling control unit gives a command to cause the connection switching unit to perform a predetermined switching operation when the abnormality determination unit detects that the abnormality has occurred in any of the electronic control devices. The left and right rear wheels of the vehicle are made independent so that the rear wheel on the inner wheel side of the turning of the vehicle is fixed at the neutral position and a command is given to drive only the rear wheel on the outer wheel side. In the rear wheel steering control device that steers the vehicle, it is possible to prevent the behavior of the vehicle from becoming unstable when either one of the left and right becomes uncontrollable due to an abnormality in the electronic control device that controls the actuator. It can .
A rear wheel steering control device according to a second aspect of the present invention is a rear wheel steering control device for controlling a rear wheel steering device capable of controlling a steering angle and a toe angle of a rear wheel of a vehicle, the rear wheel steering The device comprises a pair of actuators for independently steering the left and right rear wheels independently, each of the actuators comprising a steering motor, a rotation angle detector for detecting the rotation angle of the steering motor, and the steering And an absolute position detector capable of detecting an absolute position of an output portion of a motor driven actuator, and the rear wheel steering control device has a pair of electronic control devices for controlling the pair of actuators. And a connection switching unit that alternately switches between the steering motor, the rotation angle detector, and the absolute position detector, which respectively configure the pair of actuators, and the pair of electronic control devices, and the pair of electrons An abnormality determination unit that detects that an abnormality that can not drive the actuator normally occurs in any one electronic control device of the control devices, and the abnormality in any one of the electronic control devices by the abnormality determination unit Is detected, the steering motor, the rotation angle detector, and the absolute position detector in the actuator normally connected to the electronic control unit where the abnormality is detected are connected to the other electronic control unit And an abnormality handling control unit for causing the connection switching unit to perform switching operation, and the abnormality handling control unit detects that the abnormality has occurred in any one of the electronic control devices by the abnormality determination unit. When it is done, the command of the switching operation to the connection switching unit and the command of the turning to each of the actuators are performed according to a defined rule. When the abnormality determination unit detects that the abnormality has occurred in any one of the electronic control devices, the abnormality handling control unit initially generates an abnormality by the connection switching unit. Control is performed to move the inner ring side gradually to the neutral position while switching the connection with the control device every predetermined time, and at the same time to move the rear wheel to be the outer ring side of turning to a predetermined angle. For this reason, in the rear wheel steering control device that steers the left and right rear wheels of the vehicle independently of each other, the vehicle can not be steered by either the left or the right due to an abnormality in the electronic control device that controls the actuator It is possible to prevent the behavior of the device from becoming unstable.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic explanatory drawing of the motor vehicle carrying the rear-wheel steering apparatus which applies the rear-wheel steering control apparatus which concerns on one Embodiment of this invention. It is a block diagram of the conceptual composition of the same rear wheel steering control device.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic explanatory view of a vehicle equipped with a rear wheel steering device to which the rear wheel steering control device according to this embodiment is applied. The left and right front wheels 2 and 3 of the vehicle 1, which is an automobile, are steered to the left and right by transmitting the turning angles of the steering wheel 4 to the front wheel turning unit 5 which is a main turning unit. The front wheel steering system 5 includes, for example, a rack and pinion. The outputs of the steering angle sensor 6, the vehicle speed sensor 7, and the yaw rate sensor 8 provided to the steered shaft of the steering wheel 4 are input to the electronic control unit 9. The electronic control unit 9 is a main control unit that performs control such as coordinated control and overall control of the entire automobile 1 and is generally abbreviated as an ECU.

  The left and right rear wheels 10, 11 are fixed to a chassis (not shown) by a rear wheel steering device 12, and knuckle arms Na, Nb corresponding to respective tie rods connected to the rear wheel steering device 12 are It is steered through. The rear wheel steering device 12 can steer the left and right rear wheels 10 and 11 independently of each other by a pair of left and right steering motors (left) 25L and 25R (right). Regarding the turning angles of the rear wheels 10 and 11, the target turning angles determined by the electronic control unit 9 in accordance with the input of the traveling information of the automobile 1, such as the steering angle sensor 6, the vehicle speed sensor 7 and the yaw rate sensor 8 The rear wheel steering control device 13 receives, and the rear wheel steering control device 13 independently controls the left and right rear wheels 10 and 11, respectively.

  The rear wheel steering device 12 arranges an actuator for steering the rear wheels 10 and 11 in the same phase or in the opposite phase with respect to the front wheel steering angle. For example, this actuator is a linear motion actuator composed of a slide screw without reverse input or a ball screw with a reverse input prevention mechanism, and the steering motor 25L is connected via a reduction gear with a nut screwed with these. , 25R to convert it into a linear movement of the output part of the actuator. This direct acting actuator is constituted by a first actuator 14L and a second actuator 14R in order to drive the left and right rear wheels 10, 11 independently. The first actuator 14L is a driving means for turning the left rear wheel 10, and the second actuator 14R is a driving means for turning the right rear wheel 11. Since the first and second actuators 14L and 14R have the same configuration, only one of the actuators 14L and 14R will be described, and the description of the other may be omitted unless particularly necessary.

  FIG. 2 is a block diagram of a conceptual configuration of the rear wheel steering control device 13 that controls the rear wheel steering device 12 (FIG. 1) having the above-described configuration. The rear wheel steering control device 13 independently controls the first and second actuators 14L and 14R that steer the left and right rear wheels 10 and 11 (FIG. 1), respectively. Have. The electronic control devices 13L and 13R have the same control configuration. Therefore, in the following description, only the first electronic control device 13L will be described, and the description of the second electronic control device 13R may be omitted. In addition, regarding the steering motor (left) 25L, the rotation angle detector 26L, and the absolute position detector 27L, which are components of the first actuator 14L, the second actuator 14R also has the same components, and the left and right The corresponding components are indicated by changing the sign of L to R.

  The connection switching unit 31 includes the motor drive units 20L and 20R, the steering motor (left) 25L, and the steering motor (right) 25R, the input I / F units 18L and 18R and the rotation angle detectors 26L and 26R, and the absolute Connection switching between the position detectors 27L and 27R is performed. In the connection switching unit 31, the motor drive unit 20L is normally connected to the steering motor (left) 25L, and the input I / F unit 18L is connected to the rotation angle detection unit 26L and the absolute position detector 27L. The motor drive unit 20R is connected to the steering motor (right) 25R, and the input I / F unit 18R is connected to the rotation angle detection unit 26R and the absolute position detector 27R.

  The connection switching unit 31 can switch the connection between the electronic control device 13L and the first actuator 14L and the connection between the electronic control device 13R and the second actuator 14R according to a command from the electronic control unit 9. Therefore, if necessary, connect the motor drive unit 20L to the steering motor (right) 25R, connect the input I / F unit 18L to the rotation angle detection unit 26R and the absolute position detector 27R, turn the motor drive unit 20R to the steering motor It is possible to connect to (left) 25L and switch the connection of the input I / F unit 18R to the rotation angle detection unit 26L and the absolute position detector 27L.

  The electronic control unit 13L includes a microprocessor 16L, an input interface unit 17L for an input signal on the command side obtained from the electronic control unit 9 which is an upper control means, and an input interface for an input signal on the detection side obtained from the first actuator 14L. It has a section 18L, an output interface section 19L, and a motor drive section 20L. Note that the input interface units 17L and 18L on the command side and the detection side may be electronic elements different from each other or may be parts of one electronic element.

  The target value of the rear wheel turning angle determined by the electronic control unit 9 is sent to the microprocessor 16L via the input interface section 17L on the command side, and sent to the motor control target value computing section 22L. In order to execute control of the steering motor (left) 25L in the microprocessor 16L, the result calculated by the motor control target value calculator 22L (in this embodiment, the steering motor calculated from the steering angle (left) A motor drive command based on the rotational speed 25L is transmitted to the motor drive unit 20L via the output interface unit 19L.

  When, for example, a brushless motor is used as the steering motor (left) 25L, the basic control is control of torque (current), speed, and position, and the control target of this control system is the position (steering angle), A control system (not shown) mounted on the microprocessor 16L is a composite control system that configures a speed control system and a position control system on the upper side of the current control system. Therefore, the motor drive command value is a target steering angle based on feedback values such as the motor current detection value and the rotation angle detection value obtained from the motor current detection unit 24L, in addition to the calculation result calculated by the command from the electronic control unit 9. It is controlled to reach.

  The absolute position detector 27L monitors the absolute position of the first actuator 14L. The absolute position is detected when the power is turned on, for example, when the ignition (not shown) of the vehicle is turned on, and the subsequent control is a rotation angle obtained from the rotation angle detector 26L based on the detected absolute position. Implement position control. These control systems are implemented, for example, in the microprocessor 16 so as to perform control by software operation.

Next, the problems in the above configuration and the measures therefor will be described.
For example, when a malfunction occurs in any of motor drive unit 20L, output I / F unit 19L, motor control target value calculation unit 22L, input I / F unit 18L, etc. inside the electronic control device 13L while the vehicle is traveling, the left side The rear wheel 10 may turn or not turn to an unintended angle. As a result, the vehicle flows in a direction not intended by the driver.

As this countermeasure, in this embodiment, the connection switching unit 31 is provided, and the abnormality coping unit 34 is provided. The abnormality coping unit 34 is provided, for example, in the electronic control unit 9. The abnormality coping unit 34 includes an abnormality determination unit 32 and an abnormality handling control unit 33. The abnormality determination unit 32 is a means for detecting that an abnormality in which the actuators 14L and 14R can not be normally driven has occurred in one of the electronic control units 13L and 13R in the pair. . The abnormality determination by the abnormality determination unit 32 may be performed by the signal at any one of the electronic control devices 13L and 13R, at any other place of the electronic control devices 13L and 13R, or at any one of the electronic control device 9 and the actuators 14L and 14R. It is performed by comparing with a signal.
When the abnormality determination unit 32 detects that the abnormality that can not be driven normally is generated in the one of the electronic control devices 13L and 13R, the abnormality handling control unit 33 detects the occurrence of the abnormality. The steering motors 25L and 25R, the rotation angle sensors 26L and 26R, and the absolute position detectors 27L and 27R in the actuators 14L and 14R normally connected to the control devices 13L and 13R are connected to the other electronic control devices 13L and 13R. Means for causing the connection switching unit 31 to perform the switching operation. The abnormality handling control unit 33 issues a switching operation command to the connection switching unit 31 and a steering command to the actuators 14L and 14R in the following manner according to a defined rule. The defined rules may be arbitrarily determined regardless of the contents, but a plurality of examples will be described later.

Specifically, when the abnormality determination unit 32 detects an abnormality that the electronic control device 13L can not be driven normally, the abnormality handling control unit 33 determines whether the first actuator 14L is normal. For example, the abnormality determination unit 32 instructs the connection switching unit 31 to connect the electronic control device 13R to the first actuator 14L. Thereby, the connection switching unit 31 connects the motor drive unit 20L to the steering motor (right) 25R, and connects the input I / F unit 18L to the rotation angle detection unit 26R and the absolute position detector 27R. Further, the motor drive unit 20R is connected to the steering motor (left) 25L, and the input I / F unit 18R is connected to the rotation angle detection unit 26L and the absolute position detector 27L. At this time, the function of the electronic control unit 13L is invalidated by, for example, turning off the power to the electronic control unit 13L. After the connection switching, if the first actuator 14L is driven from the electronic control device 13R, it can be determined from the position of the first actuator 14L, the current value of the steering motor (left) 25L, etc. whether the actuator 14L is normal.
If an abnormality in the electronic control unit 13R opposite to the above is detected, the same control as described above is performed for the respective means reverse to the left or right, that is, whether the actuator 14R is normal or not. Make a decision.

  When the first actuator 14L is normal, the abnormality handling control unit 32 controls the rear wheel steering control method to steer both inner and outer rings. Switch to “Control to steer to the target steering angle”.

The “control for fixing the rear wheel inner side to the neutral position and steering only to the rear wheel outer side to the target steering angle” will be described. The abnormality handling control unit 32 can determine from the turning angle of the steering wheel 4 which one of the first actuator 14L and the second actuator 14R drives the inner wheel in cornering. Here, when an abnormality occurs, it is assumed that the first actuator 14L is on the inner ring side at the beginning and the first actuator 14L is not at the neutral position of the rear wheel steering device 12.
The abnormality handling control unit 32 instructs the connection switching unit 31 to switch the connection, and switches between the electronic control device 13R and the first actuator 14L and the second actuator 14R while the both actuators are operated via the electronic control device 13R. Controls 14L and 14R.

At the initial stage of occurrence of abnormality, the abnormality handling control unit 33 first controls the first actuator 14L to move to the neutral position when the electronic control device 13R and the first actuator 14L on the inner ring side are connected. Further, when the electronic control unit 13R is connected to the second actuator 14R on the outer ring side, the abnormality handling control unit 33 controls to move to a predetermined steering position.
At this time, the connection switching unit 31 switches the connection between the electronic control unit 13R and the first actuator 14L and the second actuator 14R alternately at predetermined time intervals to target the rear wheel to be the inner ring and the outer ring little by little. Turn to position. The predetermined time to switch alternately may be set arbitrarily, but is, for example, a time in milliseconds.
When the first actuator 14L on the inner ring side reaches the neutral position, the drive control for switching between the inner and outer rings at predetermined intervals by the connection switching unit 31 is stopped, and the electronic controller 13R is switched to the second actuator 14R on the outer ring side. It connects to it and turns control the outer ring.

Also, when the driver turns the steering wheel in the reverse direction and the first actuator 14L switches to the outer ring side, the connection switching unit 31 switches the connection so that the electronic control unit 13R is connected to the first actuator 14L. The device 13R steers the first actuator 14L on the outer ring side. Thus, the connection switching unit 31 switches connection each time so that the electronic control unit 13R is always connected to the actuator on the outer ring side.
When the steering angle of the steering wheel 4 is neutral, the electronic control unit 13R is connected to one of the actuators 14L and 14R.

In the above-mentioned “control to fix the rear wheel inner side to the neutral position and steer only to the rear wheel outer side to the target steering angle”, the total of the rear wheel cornering forces is smaller than when steering with both normal wheels, and the vehicle behavior In order to enhance the stability, the turning amount of the outer ring may be made larger than usual.
According to the above method, the behavior of the vehicle can be prevented from becoming unstable, and the vehicle behavior stability can be enhanced compared to the case where the rear wheel is in the neutral position.
Even when a defect occurs in the electronic control unit 13R reverse to the above, the electronic control unit 13L controls the first and second actuators 14L and 14R in the same manner as described above except that the reverse is the same. Take measures with the method of

Note that while the connection switching unit 31 connects and controls the electronic control device 13R and the first and second actuators 14L and 14R due to the occurrence of an abnormality in the electronic control device 13L, the electronic control device 13L and the first and first It is not necessary to connect the two actuators 14L and 14R. Similarly, while the electronic control device 13L is connected to the electronic control device 13L and the first and second actuators 14L and 14R and controlled by the occurrence of an abnormality of the electronic control device 13R, the electronic control device 13R and the first and second actuators 14L and 14R You do not have to connect with
In addition, switching between the steering motor (left) 25L and the steering motor (right) 25R and the motor drive units 20L and 20R is performed when the motor drive unit current is OFF (current value is zero) or a current smaller than normal Change to a value and then switch.

  Next, another example of the control rule performed by the abnormality handling control unit 33 will be described. In this example, as in the above example, the case where an abnormality in which the first electronic control device 13L can not be driven normally occurs will be described. First, similarly to the above example, it is determined whether the actuator 14L is normal. After this, control is performed as follows.

  If the first actuator 14L is normal, the abnormality handling control unit 33 of the electronic control unit 9 shifts to control to steer the first actuator 14L and the second actuator 14R to the neutral position.

  The abnormality handling control unit 33 instructs the connection switching unit 31 to switch the connection, and switches between the electronic control device 13R and the first actuator 14L and the second actuator 14R while the both are controlled via the electronic control device 13R. The actuators 14L, 14R are steered to the neutral position. At this time, the connection switching unit 31 moves the inner ring and the outer ring little by little at the same time by alternately switching the connection between the electronic control unit 13R, the first actuator 14L, and the second actuator 14R every predetermined time. Steer to the neutral position. For movement of the first actuator 14L and the second actuator 14R to the neutral position, for example, the outer ring side to which a large load is applied during turning is first steered to the neutral position, and then the inner ring side is steered to the neutral position. The two actuators may be moved in order.

Also by the above method, by turning the first actuator 14L and the second actuator 14R to the neutral position, it is possible to prevent the behavior of the vehicle 1 from becoming unstable.
Also in the case of this method, even when a defect occurs in the electronic control device 13R which is the reverse of the above, the electronic control device 13L to the first and second actuators 14L, 14L, as described above, except that the problem is the reverse of the left and the right. Control 14R and take measures in the same way.

  As mentioned above, although the form for implementing this invention was demonstrated based on embodiment, embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is indicated not by the above description but by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

DESCRIPTION OF SYMBOLS 1 ... Vehicle 5 ... Front wheel steering apparatus 6 ... Steering angle sensor 9 ... Electronic control unit 10, 11 ... Rear wheel 12 ... Rear wheel steering apparatus 13 ... Rear wheel steering control apparatus 13L, 13R ... Electronic control apparatus 14L, 14R ... Actuators 20L, 20R ... motor drive units 24L, 24R ... motor current detection units 25L, 25R ... steering motors 26L, 26R ... rotation angle detectors 27L, 27R ... absolute position detectors 31 ... one connection switching unit 32 ... abnormality determination unit 33: Abnormality corresponding control unit 34: Abnormality dealing means

Claims (2)

A rear wheel steering control device for controlling a rear wheel steering device capable of controlling a steering angle and a toe angle of a rear wheel of a vehicle,
The rear wheel steering apparatus includes a pair of actuators for independently steering the left and right rear wheels independently, and each of the actuators includes a steering motor and a rotation angle detector for detecting a rotation angle of the steering motor An absolute position detector capable of detecting an absolute position of an output portion of the actuator driven by the steering motor;
The rear wheel steering control device has a pair of electronic control devices that respectively control the pair of actuators, and the steering motor, the rotation angle detector, and the absolute position detector that respectively configure the pair of actuators A connection switching unit that alternately switches connection with the pair of electronic control devices;
An abnormality determination unit that detects that an abnormality that prevents the normal operation of the actuator from occurring in any one electronic control unit of the pair of electronic control units;
When the abnormality determination unit detects that the abnormality occurs in any one of the electronic control devices, the steering motor and the rotation angle of the actuator that is normally connected to the electronic control device in which the abnormality is detected. detector, and an absolute position detector e Bei an abnormality handling control unit to perform a switching operation to the connection switching unit so as to be connected to the other of the electronic control device,
The abnormality handling control unit instructs the switching operation to the connection switching unit and the transfer to each of the actuators when the abnormality determination unit detects that the abnormality has occurred in any of the electronic control devices. Command the rudder in accordance with the established rules,
The abnormality handling control unit gives a command to cause the connection switching unit to perform a predetermined switching operation when the abnormality determination unit detects that the abnormality has occurred in any of the electronic control devices, A rear wheel steering control device for giving an instruction to drive so that only the rear wheel on the outer wheel side is steered while the rear wheel on the inner wheel side of turning of the vehicle is fixed at the neutral position. A rear wheel steering control device for controlling a rear wheel steering device capable of controlling a steering angle and a toe angle of a rear wheel of a vehicle,
The rear wheel steering apparatus includes a pair of actuators for independently steering the left and right rear wheels independently, and each of the actuators includes a steering motor and a rotation angle detector for detecting a rotation angle of the steering motor An absolute position detector capable of detecting an absolute position of an output portion of the actuator driven by the steering motor;
The rear wheel steering control device has a pair of electronic control devices for controlling the pair of actuators, and
A connection switching unit that alternately switches connections between the steering motor, the rotation angle detector, and the absolute position detector, which respectively configure the pair of actuators, and the pair of electronic control devices;
An abnormality determination unit that detects that an abnormality that prevents the normal operation of the actuator from occurring in any one electronic control unit of the pair of electronic control units;
When the abnormality determination unit detects that the abnormality occurs in any one of the electronic control devices, the steering motor and the rotation angle of the actuator that is normally connected to the electronic control device in which the abnormality is detected. A detector, and an abnormality handling control unit that causes the connection switching unit to perform switching operation so that the absolute position detector is connected to the other electronic control device;
The abnormality handling control unit instructs the switching operation to the connection switching unit and the transfer to each of the actuators when the abnormality determination unit detects that the abnormality has occurred in any of the electronic control devices. Command the rudder in accordance with the established rules,
The abnormality handling control unit is configured such that when the abnormality determination unit detects that the abnormality has occurred in any of the electronic control devices, the connection switching unit initially generates an abnormality with the actuator and the electronic control device. The rear wheel steering control device performs control to move the inner wheel side gradually to the neutral position while switching the connection with each at a predetermined time, and at the same time move the rear wheel to be the outer wheel side of turning to a predetermined angle.

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