Steering control device

Abstract

To provide a steering control device that enhances a crime prevention property.SOLUTION: A reaction force control device 40 allows a vehicle control device to start a power train when the preparation process triggered by the activation of a vehicle power supply is completed. Then, the reaction force control device 40 transitions to a normal control state being the state where reaction force control to generate steering reaction force in the reaction force motor is executed, when recognizing that the power train has been started. The reaction force control device 40 requests the vehicle control device to stop the operation of the power train when recognizing that the power train has been started even if it does not allow the vehicle control device to start the power train. However, the reaction force control device 40 does not request the vehicle control device to stop the operation of the power train even when information exchange that does not conform to a predetermined pattern is performed with the vehicle control device in a case where the vehicle power supply is turned on, and the vehicle is not in a drivable state.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a steering control device. [Background technology]

[0002] Conventionally, there exists a so-called steer-by-wire type steering device in which the power transmission between the steering wheel and the steered wheels is separated (see, for example, Patent Document 1). This steering device is equipped with a reaction mechanism having a reaction motor which is a generating source of a steering reaction force applied to a steering shaft, and a steering mechanism having a steering motor which is a generating source of a steering force for turning the steered wheels. When the vehicle is traveling, a control device of the steering device generates a steering reaction force through power supply control to the reaction motor, and steers the steered wheels through power supply control to the steering motor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2006-321434 A Summary of the Invention [Problem to be solved by the invention]

[0004] Vehicles are required to have higher security features, and the steering devices installed in the vehicles are also required to have higher security features. [Means for solving the problem]

[0005] A steering control device that can solve the above problem has a control circuit that controls the drive of a reaction force motor that generates a steering reaction force applied to a steering wheel that is separated from the steered wheels of a vehicle. The control circuit is configured to request the vehicle control device to stop operation of a powertrain including a drive source for driving the vehicle when information that does not follow a predetermined pattern is exchanged between the vehicle control device and the steering wheel when a vehicle power source is turned on and the vehicle is not in a state where it can be driven, and the control circuit is configured not to request the vehicle control device to stop operation of the powertrain when information that does not follow a predetermined pattern is exchanged between the vehicle control device and the steering wheel when the vehicle power source is turned on and the vehicle is not in a state where it can be driven.

[0006] There is a concern that some kind of fraudulent act may falsify information exchanged between the control circuit and the vehicle control device. There is also a concern that the vehicle control device may output information at an incorrect timing due to some cause. In this regard, according to the above configuration, when information is exchanged between the control circuit and the vehicle control device that does not follow a predetermined pattern, the operation of the powertrain is stopped. Since the vehicle cannot run using the power of the driving source for running, crime prevention is improved. However, even if information is exchanged between the control circuit and the vehicle control device that does not follow a predetermined pattern, the vehicle control device is not required to stop the operation of the powertrain when the vehicle is not in a state where it can run. Since the vehicle is not in a state where it can run, safety or crime prevention can be ensured.

[0007] In the above steering control device, when the vehicle is not in a state in which it can travel, the shift range of the vehicle may not be a shift range in which it can travel. With this configuration, if the shift range of the vehicle is not a shift range that allows the vehicle to run, the vehicle cannot run using the power of the drive source for running. The shift range is a suitable condition for determining whether the vehicle is in a state in which it can run.

[0008] In the steering control device, the vehicle may have a remote function for remotely controlling an electronic device mounted on the vehicle in a parked state by using a wireless communication technique. In this case, when the vehicle is not in a state in which it can run, the remote function may be turned on.

[0009] In this configuration, the remote function is used, for example, when the vehicle is in a parked state. Therefore, when the remote function is on, the vehicle is in a parked state, that is, the vehicle cannot run using the power of the drive source for running. The on of the remote function is a suitable condition for determining whether the vehicle is in a runnable state.

[0010] In the above-mentioned steering control device, the control circuit may be configured to permit the vehicle control device to start the powertrain when the preparatory processing executed in response to the vehicle power supply being turned on is completed, and when it is recognized via the vehicle control device that the powertrain has started, to transition to a normal control state in which reaction force control is executed to generate a steering reaction force in the reaction force motor.

[0011] According to this configuration, when the preparation process for the reaction force control is completed, the control circuit permits the vehicle control device to start the powertrain. That is, the vehicle control device waits for the control circuit to permit the powertrain to be started before starting the powertrain. Therefore, the vehicle can only travel after the preparation process for the control circuit is completed. Therefore, the vehicle can start traveling in a safer state for the driver.

[0012] In the above steering control device, the control circuit may be configured to request the vehicle control device to stop operation of the powertrain when it is recognized via the vehicle control device that the powertrain has started even though the vehicle control device has not been permitted to start the powertrain.

[0013] When the control circuit does not permit the vehicle control device to start the powertrain but it is recognized that the powertrain is starting, there is a risk that the permission given to the vehicle control device has been forged, for example, by fraudulent acts such as impersonation. In this regard, according to the above configuration, when there is a risk that the permission given to the vehicle control device has been forged, the control circuit requests the vehicle control device to stop the operation of the powertrain. The vehicle control device stops the operation of the powertrain in response to a request from the control circuit, thereby improving crime prevention.

[0014] In the steering control device, the vehicle may have a remote function for remotely controlling an electronic device mounted on the vehicle in a parked state by using a wireless communication technology. In this case, the vehicle control device may be configured to start the powertrain without permission of the control circuit when the remote function is turned on.

[0015] When this configuration is adopted, when the remote function is turned on, the powertrain starts without the permission of the control circuit. Therefore, there is a risk that the control circuit will request the vehicle control device to stop the operation of the powertrain. However, when the vehicle is not in a state in which it can be driven, the control circuit will not request the vehicle control device to stop the operation of the powertrain even if the powertrain is started without the permission of the control circuit. Therefore, while ensuring the function of stopping the operation of the powertrain when the powertrain is started without the permission of the control circuit, the start of the powertrain accompanying the turning on of the remote function is permitted. Therefore, convenience for the user of the vehicle is ensured.

[0016] In the above steering control device, the preparation process may include a midpoint learning process that learns a steering neutral position of the steering wheel by moving the steering wheel to a first operating limit and then moving it in a reverse direction to a second operating limit, and a steering angle synchronization process that corrects the rotational position of the steering wheel so that the rotational position of the steering wheel becomes a rotational position corresponding to the steered position of the steered wheels.

[0017] For example, if the vehicle starts traveling while the control circuit is in the middle of executing the midpoint learning process or the steering angle synchronization process, the driver may have difficulty steering the steering wheel in the intended steering direction. This is because the steering wheel is in an automatic rotation state while the midpoint learning process or the steering angle synchronization process is being executed. In this regard, according to the above configuration, when the preparation process for the reaction force control is completed, the control circuit permits the vehicle control device to start the powertrain. Therefore, the vehicle can only travel after the preparation process of the control circuit is completed. Therefore, the vehicle can start traveling in a safer state for the driver. The driver does not feel uncomfortable. Effect of the Invention

[0018] According to the steering control device of the present invention, it is possible to improve crime prevention. [Brief description of the drawings]

[0019] [Figure 1] 1 is a configuration diagram of a steer-by-wire type steering device in which an embodiment of a steering control device is mounted. [Diagram 2] FIG. 2 is a block diagram of a reaction force control device and a steering control device according to an embodiment. [Diagram 3] 5 is a time chart showing a comparative example of start-up sequences in a reaction force control device and a vehicle control device. [Figure 4] 5 is a flowchart showing a processing procedure for determining whether to permit starting of a power train of a vehicle by a reaction force control device according to an embodiment. [Diagram 5] 4 is a time chart showing a first pattern of a start-up sequence in the reaction force control device and the vehicle control device according to an embodiment. [Figure 6] 4 is a flowchart showing a processing procedure for determining a vehicle stop request by the reaction force control device according to the embodiment. [Figure 7] 5 is a time chart showing a second pattern of the start-up sequence in the reaction force control device and the vehicle control device according to the embodiment. [Figure 8] 6 is a time chart showing a third pattern of the start-up sequence in the reaction force control device and the vehicle control device according to the embodiment. [Figure 9] 6 is a time chart showing a fourth pattern of the start-up sequence in the reaction force control device and the vehicle control device according to the embodiment. [Figure 10] 6 is a time chart showing a fifth pattern of the start-up sequence in the reaction force control device and the vehicle control device according to the embodiment. [Figure 11] 13 is a time chart showing a sixth pattern of the start-up sequence in the reaction force control device and the vehicle control device according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] An embodiment in which the steering control device is embodied in a steer-by-wire type steering device will be described below. As shown in FIG. 1, a vehicle steering device 10 has a steering shaft 12 connected to a steering wheel 11. Steering device 10 also has a steered shaft 13 extending along the vehicle width direction (left-right direction in FIG. 1). Steered wheels 15 are connected to both ends of steered shaft 13 via tie rods 14, respectively. The steered angle θw of steered wheels 15 is changed by linear movement of steered shaft 13. Steering shaft 12 and steered shaft 13 constitute a steering mechanism of the vehicle. However, power transmission between steering shaft 12 and steered shaft 13, and therefore between steering wheel 11 and steered wheels 15, is separated. Note that FIG. 1 shows only steered wheels 15 on one side.

[0021] The steering device 10 has a reaction motor 21 and a reduction mechanism 22. The reaction motor 21 is a generating source of a steering reaction force. The steering reaction force is a force acting in a direction opposite to the direction of operation of the steering wheel 11 by the driver. The rotating shaft of the reaction motor 21 is connected to the steering shaft 12 via the reduction mechanism 22. The torque of the reaction motor 21 is applied to the steering shaft 12 as a steering reaction force. By applying the steering reaction force to the steering wheel 11, it is possible to give the driver an appropriate sense of responsiveness.

[0022] The reaction motor 21 is, for example, a three-phase brushless motor. The reaction motor 21 has a first winding group N11 and a second winding group N12. The first winding group N11 and the second winding group N12 are wound around a common stator (not shown). The first winding group N11 and the second winding group N12 have equivalent electrical characteristics.

[0023] Steering device 10 has a turning motor 31 and a reduction mechanism 32. Steering motor 31 is a source of turning force. The turning force refers to power for steering steered wheels 15. A rotating shaft of steering motor 31 is connected to pinion shaft 33 via reduction mechanism 32. Pinion teeth 33a of pinion shaft 33 mesh with rack teeth 13a of steered shaft 13. The torque of steering motor 31 is applied to steered shaft 13 via pinion shaft 33 as a turning force. In response to the rotation of steering motor 31, steered shaft 13 moves along the vehicle width direction.

[0024] The steering motor 31 is, for example, a three-phase brushless motor. The steering motor 31 has a first winding group N21 and a second winding group N22. The first winding group N21 and the second winding group N22 are wound around a common stator (not shown). The first winding group N21 and the second winding group N22 have equivalent electrical characteristics.

[0025] The steering device 10 has a reaction force control device 40. The reaction force control device 40 controls the driving of the reaction force motor 21, which is the object to be controlled. The reaction force control device 40 executes reaction force control in which the reaction force motor 21 generates a steering reaction force corresponding to the steering torque Th. The reaction force control device 40 calculates a target steering reaction force based on the steering torque Th detected through a torque sensor 23. The torque sensor 23 is provided on the steering shaft 12. The reaction force control device 40 controls the power supply to the reaction force motor 21 so that the actual steering reaction force applied to the steering shaft 12 coincides with the target steering reaction force. The reaction force control device 40 controls the power supply to the two systems of winding groups in the reaction force motor 21 independently for each system.

[0026] The reaction force control device 40 has a first circuit system 41 and a second circuit system 42. The first circuit system 41 controls the power supply to the winding group N11 of the first system in the reaction force motor 21 in response to the steering torque Th detected through the torque sensor 23. The second circuit system 42 controls the power supply to the winding group N12 of the second system in the reaction force motor 21 in response to the steering torque Th detected through the torque sensor 23.

[0027] The reaction force control device 40 and the on-board vehicle control device 60 are connected to each other via an on-board network 61. The on-board network 61 is, for example, a CAN (Controller Area Network). The reaction force control device 40 and the on-board vehicle control device 60 exchange information with each other via the on-board network 61. The vehicle control device 60 controls the running of the vehicle. Specifically, the vehicle control device 60 controls, for example, the power train of the vehicle. The power train includes a driving source for running the vehicle and a power transmission mechanism. The driving source for running includes, for example, an engine or a motor. The power transmission mechanism is a mechanism for transmitting the power generated by the driving source for running to the drive wheels. The reaction force control device 40 controls the driving of the reaction force motor 21 based on information exchanged between the reaction force control device 40 and the vehicle control device 60.

[0028] The steering device 10 has a steering control device 50. The steering control device 50 controls the driving of the steering motor 31 which is the object of control. The steering control device 50 executes steering control in which the steering motor 31 generates a steering force for turning the steered wheels 15 according to the steering state. The steering control device 50 takes in the steering angle θs detected through the steering angle sensor 24 and the stroke Xw of the steered shaft 13 detected through the stroke sensor 34. The stroke Xw is a displacement amount based on the neutral position of the steered shaft 13, and is a state variable in which the steering angle θw is reflected. The steering angle sensor 24 is provided between the torque sensor 23 of the steering shaft 12 and the reduction mechanism 22. The stroke sensor 34 is provided in the vicinity of the steered shaft 13.

[0029] The steering control device 50 calculates a target steering angle of the steered wheels 15 based on the steering angle θs detected through the steering angle sensor 24. The steering control device 50 calculates the steering angle θw based on the stroke Xw of the steered shaft 13 detected through the stroke sensor 34. The steering control device 50 controls the supply of power to the steering motor 31 so as to match the steering angle θw calculated based on the stroke Xw with the target steering angle. The steering control device 50 controls the supply of power to the two systems of winding groups in the steering motor 31 independently for each system.

[0030] The steering control device 50 has a first circuit system 51 and a second circuit system 52. The first circuit system 51 controls the power supply to the winding group N21 of the first system in the steering motor 31, based on the steering angle θs detected through the steering angle sensor 24 and the stroke Xw of the steering shaft 13 detected through the stroke sensor 34. The second circuit system 52 controls the power supply to the winding group N22 of the second system in the steering motor 31, based on the steering angle θs detected through the steering angle sensor 24 and the stroke Xw of the steering shaft 13 detected through the stroke sensor 34.

[0031] Incidentally, a so-called mechanically and electrically integrated reaction force actuator may be configured by integrally providing reaction force control device 40 and reaction force motor 21. Also, a so-called mechanically and electrically integrated steering actuator may be configured by integrally providing steering control device 50 and steering motor 31. Reaction force control device 40 and steering control device 50 constitute a steering control device.

[0032] <Reaction force control device> Next, the configuration of the reaction force control device will be described in detail. 2, the reaction force control device 40 has a first circuit system 41 and a second circuit system 42. The first circuit system 41 has a first reaction force control circuit 41A and a motor drive circuit 41B. The second circuit system 42 has a second reaction force control circuit 42A and a motor drive circuit 42B.

[0033] The first reaction force control circuit 41A is configured by a processing circuit including: 1. one or more processors that operate according to a computer program (software); 2. one or more dedicated hardware circuits such as an application specific integrated circuit (ASIC) that executes at least some of various processes; and 3. a combination thereof. The processor includes a central processing unit (CPU). The processor also includes memory such as random-access memory (RAM) and read-only memory (ROM). The memory stores program code or instructions configured to cause the CPU to execute processes. Memory, i.e., non-transitory computer-readable media, includes any available media that can be accessed by a general-purpose or special-purpose computer.

[0034] The first reaction force control circuit 41A calculates a target steering reaction force to be generated in the reaction force motor 21 based on the steering torque Th detected through the torque sensor 23, and calculates a first current command value for the winding group N11 of the first system according to the value of the calculated target steering reaction force. However, the first current command value is set to a value that is half (50%) of the amount of current (100%) required for the reaction force motor 21 to generate the target steering reaction force. The first reaction force control circuit 41A generates a drive signal (PWM signal) for the motor drive circuit 41B by executing current feedback control that makes the value of the actual current supplied to the winding group N11 of the first system follow the first current command value.

[0035] The motor drive circuit 41B is a PWM inverter in which three legs corresponding to each of the three phases (U, V, W) are connected in parallel, with two switching elements such as field effect transistors (FETs) connected in series as a basic unit. The motor drive circuit 41B converts DC power supplied from the battery into three-phase AC power by switching the switching elements of each phase based on a drive signal generated by the first reaction force control circuit 41A. The three-phase AC power generated by the motor drive circuit 41B is supplied to the first system winding group N11 of the reaction force motor 21 via a power supply path of each phase formed of a bus bar or a cable. As a result, the first system winding group N11 generates a torque according to the first current command value.

[0036] The second reaction force control circuit 42A basically has the same configuration as the first reaction force control circuit 41A. The second reaction force control circuit 42A calculates a target steering reaction force to be generated in the reaction force motor 21 based on the steering torque Th detected through the torque sensor 23, and calculates a second current command value for the winding group N12 of the second system according to the value of the calculated target steering reaction force. However, the second current command value is set to a value that is half (50%) of the amount of current required for the reaction force motor 21 to generate the target steering reaction force. The second reaction force control circuit 42A generates a drive signal for the motor drive circuit 42B by executing current feedback control that makes the value of the actual current supplied to the winding group N12 of the second system follow the second current command value.

[0037] The motor drive circuit 42B basically has the same configuration as the motor drive circuit 41B. The motor drive circuit 42B converts DC power supplied from the battery into three-phase AC power based on a drive signal generated by the second reaction force control circuit 42A. The three-phase AC power generated by the motor drive circuit 42B is supplied to the second winding group N12 of the reaction force motor 21 via a power supply path for each phase, which is made of a bus bar or a cable. As a result, the second winding group N12 generates a torque according to the second current command value. The reaction force motor 21 generates a torque that is the sum of the torque generated by the first winding group N11 and the torque generated by the second winding group N12.

[0038] Depending on the product specifications, there may be a master-slave relationship between the first circuit system 41 and the second circuit system 42 of the reaction force control device 40. In this case, for example, the first circuit system 41 may function as the master and the second circuit system 42 may function as the slave. Depending on the product specifications, the first circuit system 41 and the second circuit system 42 may have an equal relationship.

[0039] <Steering control device> Next, the configuration of the steering control device 50 will be described in detail. As shown in Fig. 2, the turning control device 50 has a first circuit system 51 and a second circuit system 52. The first circuit system 51 has a first turning control circuit 51A and a motor drive circuit 51B. The second circuit system 52 has a second turning control circuit 52A and a motor drive circuit 52B.

[0040] The first turning control circuit 51A has a configuration basically similar to that of the first reaction force control circuit 41A. The first turning control circuit 51A calculates a target turning angle of the steered wheels 15 based on the steering angle θs detected through the steering angle sensor 24. The first turning control circuit 51A calculates the turning angle θw based on the stroke Xw of the steered shaft 13 detected through the stroke sensor 34. The first turning control circuit 51A calculates a target turning force to be generated in the turning motor 31 through the execution of angle feedback control that makes the turning angle θw calculated based on the stroke Xw follow the target turning angle. The first turning control circuit 51A calculates a third current command value for the winding group N21 of the first system of the turning motor 31 according to the value of the target turning force. However, the third current command value is set to a value half (50%) of the amount of current required for the turning motor 31 to generate the target turning force. The first steering control circuit 51A generates a drive signal for the motor drive circuit 51B by executing current feedback control that causes the value of the actual current supplied to the winding group N21 of the first system to follow the third current command value.

[0041] Motor drive circuit 51B basically has the same configuration as motor drive circuit 41B. Motor drive circuit 51B converts DC power supplied from a battery into three-phase AC power based on a drive signal generated by first steering control circuit 51A. The three-phase AC power generated by motor drive circuit 42B is supplied to winding group N21 of the first system of steering motor 31 via power supply paths of each phase formed of a bus bar or a cable or the like. This causes winding group N21 of the first system to generate torque according to the third current command value.

[0042] The second turning control circuit 52A has a configuration basically similar to that of the first reaction force control circuit 41A. The second turning control circuit 52A calculates a target turning angle of the steered wheels 15 based on the steering angle θs detected through the steering angle sensor 24. The second turning control circuit 52A calculates the turning angle θw based on the stroke Xw of the steered shaft 13 detected through the stroke sensor 34. The second turning control circuit 52A calculates a target turning force to be generated in the turning motor 31 through the execution of angle feedback control for making the turning angle θw calculated based on the stroke Xw follow the target turning angle. The second turning control circuit 52A calculates a fourth current command value for the second system winding group N22 of the turning motor 31 according to the value of the target turning force. However, the fourth current command value is set to a value half (50%) of the amount of current required for the turning motor 31 to generate the target turning force. The second steering control circuit 52A generates a drive signal for the motor drive circuit 52B by executing current feedback control that causes the value of the actual current supplied to the second system winding group N22 to follow the fourth current command value.

[0043] Motor drive circuit 52B basically has the same configuration as motor drive circuit 41B. Motor drive circuit 51B converts DC power supplied from a battery into three-phase AC power based on a drive signal generated by second steering control circuit 52A. The three-phase AC power generated by motor drive circuit 52B is supplied to winding group N22 of the second system of steering motor 31 via power supply paths of each phase formed of bus bars or cables. This causes winding group N22 of the second system to generate torque according to the fourth current command value. Steering motor 31 generates torque which is the sum of torque generated by winding group N21 of the first system and torque generated by winding group N22 of the second system.

[0044] Depending on the product specifications, there may be a master-slave relationship between the first circuit system 51 and the second circuit system 52 of the steering control device 50. In this case, for example, the first circuit system 51 may function as the master and the second circuit system 52 may function as the slave. Also, depending on the product specifications, the first circuit system 51 and the second circuit system 52 may have an equal relationship.

[0045] <Communication Path> Next, the internal communication paths of the reaction force control device 40 and the steering control device 50, and the communication paths between the reaction force control device 40 and the steering control device 50 will be described.

[0046] As shown in Fig. 2, the first reaction force control circuit 41A and the second reaction force control circuit 42A exchange information with each other via a communication line L1. The information includes abnormality information of the first reaction force control circuit 41A, the second reaction force control circuit 42A, or the motor drive circuits 41B, 42B. The information also includes flag values ​​indicating various states. The first reaction force control circuit 41A and the second reaction force control circuit 42A cooperate to control the drive of the reaction force motor 21 based on the information exchanged between them.

[0047] The first turning control circuit 51A and the second turning control circuit 52A exchange information with each other via the communication line L2. The information includes abnormality information of the first turning control circuit 51A, the second turning control circuit 52A, or the motor drive circuits 51B, 52B. The information also includes flag values ​​indicating various states. The first turning control circuit 51A and the second turning control circuit 52A cooperate to control the drive of the turning motor 31 based on the information exchanged between them.

[0048] The first reaction force control circuit 41A and the first turning control circuit 51A exchange information with each other via the communication line L3. The information includes abnormality information of the first reaction force control circuit 41A, the first turning control circuit 51A, and the motor drive circuits 41B, 51B. The information also includes flag values ​​indicating various states. The first reaction force control circuit 41A and the first turning control circuit 51A work in cooperation with each other based on the information exchanged between them.

[0049] The second reaction force control circuit 42A and the second turning control circuit 52A exchange information with each other via the communication line L4. The information includes abnormality information of the second reaction force control circuit 42A, the second turning control circuit 52A, or the motor drive circuits 42B, 52B. The information also includes flag values ​​indicating various states. The second reaction force control circuit 42A and the second turning control circuit 52A operate in cooperation with each other based on the information exchanged between them.

[0050] <Comparison example of startup sequence> Next, a comparative example of the start-up sequence of the reaction force control device 40 and the vehicle control device 60 will be described. The start-up sequence is a series of processes that are executed when the vehicle power supply is turned on. While the vehicle power supply is turned off, the reaction force control device 40 and the vehicle control device 60 are maintained in a stopped state. Turning the vehicle power supply on or off also means, for example, turning on or off a start switch provided in the driver's seat. The start-up switch is operated when starting or stopping the driving source for running the vehicle, and is, for example, an ignition switch or a power switch.

[0051] First, a comparative example of the start-up sequence of the vehicle control device 60 will be described. As shown in the time chart of FIG. 3, when the vehicle power supply is turned on (time T1), the vehicle control device 60 starts executing a defined startup preparation. The startup preparation includes an initial check of the vehicle control device 60 and processing required to start the vehicle's powertrain. After the startup preparation is completed, the vehicle control device 60 starts the powertrain (mainly the driving source for traveling). When the startup processing of the powertrain is completed, the vehicle control device 60 turns on the preparation completion signal S1 (time T2). The vehicle control device 60 turns on the preparation completion signal S1 regardless of the state of the reaction force control device 40.

[0052] The ready signal S1 is information indicating whether the vehicle is ready to run, including the completion of the powertrain start-up process, and whether the vehicle is ready to run. When the ready signal S1 is on, it indicates that the vehicle is ready to run. When the ready signal S1 is off, it indicates that the vehicle is not ready to run. The ready signal S1 is transmitted to the reaction force control device 40 as an electrical signal.

[0053] Next, a comparative example of the start-up sequence of the reaction force control device 40 will be described. 3, when the vehicle power supply is turned on (time T1), the reaction force control device 40 starts up and sequentially executes an initial check, a midpoint learning process, and a steering angle synchronization process, and then transitions to an assist start waiting state. The initial check, the midpoint learning process, and the steering angle synchronization process are a series of preparatory processes required to start executing the reaction force control that causes the reaction force motor 21 to generate a steering reaction force.

[0054] The initial check is an initial inspection that is executed when the vehicle power is turned on, and includes, for example, a hardware check, initialization of the CPU (Central Processing Unit), and initialization of variables or flags.

[0055] The midpoint learning process is a process for learning the neutral steering position of the steering wheel 11. The steering device 10 has a stopper mechanism that restricts the rotation of the steering wheel 11 to set a limit to the steering angle θs of the steering wheel 11. The stopper mechanism restricts the steering range of the steering wheel 11 to less than 360°, for example. The reaction force control device 40 controls the reaction force motor 21 to move the steering wheel 11 to a first operating end and then to a second operating end. After that, the reaction force control device 40 calculates the midpoint of the steering angle θs based on the rotation angle of the reaction force motor 21 at the start and end of the reversing operation of the steering wheel 11. The midpoint of the steering angle θs corresponds to the motor midpoint, which is the rotation position of the reaction force motor 21 when the steering wheel 11 is located at the neutral steering position. The reaction force control device 40 stores the midpoint or motor midpoint of the steering angle θs as the neutral steering position of the steering wheel 11.

[0056] However, the reaction force control device 40 learns the neutral steering position of the steering wheel 11 when the vehicle power is turned on for the first time after a new battery is installed. This is because, for example, when a battery is removed from the vehicle for battery replacement work, power is no longer supplied to the reaction force control device 40, and the information about the neutral steering position stored in the reaction force control device 40 is lost.

[0057] The steering angle synchronization process is a process for correcting the rotational position of the steering wheel 11. When the rotational position of the steering wheel 11 is different from the rotational position corresponding to the steered position of the steered wheels 15, the reaction force control device 40 drives the reaction force motor 21 so that the rotational position of the steering wheel 11 becomes the rotational position corresponding to the steered position of the steered wheels 15.

[0058] The assist start waiting state is a state in which the vehicle control device 60 is waiting for confirmation of the completion of the powertrain start process after the preparation process is completed. The reaction force control device 40 judges whether or not to transition from the assist start waiting state to the normal control state according to the start state of the vehicle's powertrain. When the preparation completion signal S1 is not turned on by the vehicle control device 60, the reaction force control device 40 judges that the vehicle's powertrain start process is not completed, and maintains the assist start waiting state. When the preparation completion signal S1 is turned on by the vehicle control device 60, the reaction force control device 40 judges that the vehicle's powertrain start process is completed (time T3), and transitions from the assist start waiting state to the normal control state. The normal control state is a state in which reaction force control is performed to generate a steering reaction force in the reaction force motor 21. When in the normal control state, the reaction force control device 40 controls the drive of the reaction force motor 21 according to the steering state of the steering wheel 11.

[0059] In the time chart of FIG. 3, the vehicle control device 60 turns on the preparation complete signal S1 while the midpoint learning process is being executed, for example. However, if the vehicle is allowed to travel in this manner regardless of the state of the reaction force control device 40, the vehicle can be allowed to travel even if the reaction force control device 40 is in the middle of executing the preparation process. In this case, the following concerns arise.

[0060] For example, if the vehicle starts traveling while the reaction force control device 40 is in the middle of executing the midpoint learning process, the driver may have difficulty in steering the steering wheel 11 in the intended steering direction because the steering wheel 11 is in an automatic rotating state during the midpoint learning process.

[0061] Furthermore, even if the vehicle starts traveling while the reaction force control device 40 is in the middle of executing the steering angle synchronization process, the driver may have difficulty steering the steering wheel 11 in the intended steering direction. This is because the steering wheel 11 is in an automatic rotating state while the steering angle synchronization process is being executed. This is also due to the fact that, while the steering angle synchronization process is being executed, the rotational position of the steering wheel 11 is different from the original rotational position corresponding to the steering position of the steered wheels 15. Therefore, the reaction force control device 40 is configured to execute the following process.

[0062] <Start permission determination process> The reaction force control device 40 executes a start permission determination process when the vehicle power supply is turned on. The start permission determination process is a process for determining whether or not to permit the vehicle control device 60 to start the powertrain. The start permission determination process is executed at a predetermined control period according to a program stored in the reaction force control device 40.

[0063] 4, the reaction force control device 40 determines whether or not the preparation process for the reaction force control is completed (step S101). The preparation process is a process for preparation required to start the execution of the reaction force control, and includes an initial check, a midpoint learning process, and a steering angle synchronization process.

[0064] When it is determined that the preparation process is completed (YES in step S101), the reaction force control device 40 turns on the start permission signal S2 (step S102) and ends the process. When it is determined that the preparation process is not completed (NO in step S101), the reaction force control device 40 turns off the start permission signal S2 (step S103) and ends the process.

[0065] The start permission signal S2 is information indicating whether or not to permit the vehicle control device 60 to start the powertrain. When the start permission signal S2 is on, it indicates that the vehicle control device 60 is permitted to start the powertrain. When the start permission signal S2 is off, it indicates that the vehicle control device 60 is not permitted to start the powertrain. The start permission signal S2 is transmitted to the vehicle control device 60 as an electrical signal.

[0066] <First startup sequence pattern> Next, a first pattern of the start-up sequence will be described. As shown in the time chart of Fig. 5, when the vehicle power supply is turned on (time T1), the reaction force control device 40 starts up and sequentially executes an initial check, a midpoint learning process, and a steering angle synchronization process. When the reaction force control device 40 completes the preparation processes including the initial check, the midpoint learning process, and the steering angle synchronization process, it transitions to an assist start waiting state and turns on a start permission signal S2. The assist start waiting state is a state in which preparation for reaction force control is complete and transition to a normal control state is possible.

[0067] The vehicle control device 60 starts executing a defined startup preparation when the vehicle power supply is turned on (time T1). After the startup preparation is completed, the vehicle control device 60 transitions to a start permission waiting state (time T4). The start permission waiting state is a state in which the vehicle control device 60 waits for the reaction force control device 40 to permit the start of the powertrain, i.e., for the start permission signal S2 to be turned on.

[0068] When the vehicle control device 60 recognizes that the start permission signal S2 has been turned on in the start permission waiting state (time T5), the vehicle control device 60 starts the powertrain of the vehicle. When the execution of the powertrain start process is completed, the vehicle control device 60 turns on the preparation complete signal S1.

[0069] When the reaction force control device 40 recognizes that the preparation completion signal S1 is turned on in the assist start waiting state (time T6), the reaction force control device 40 transitions to a normal control state (time T8). The reaction force control device 40 controls the drive of the reaction force motor 21 in accordance with the steering state of the steering wheel 11.

[0070] In this way, even if the vehicle control device 60 has completed its own startup preparation, if the reaction force control device 40 has not completed the preparation process for the reaction force control, the vehicle control device 60 waits for the preparation process to be completed before starting the power train of the vehicle. Therefore, the vehicle can only travel after the reaction force control device 40 transitions to an assist start waiting state in which the reaction force control device 40 is in a state in which the reaction force control can be executed. This prevents the vehicle from entering a state in which the vehicle can travel even though the reaction force control device 40 is in the middle of executing the preparation process. In addition, the vehicle can start traveling in a state that is safer for the driver, that is, in a state in which the vehicle can be turned in the direction intended by the driver.

[0071] <Anti-spoofing measures> In the first pattern of the start-up sequence, the following is a concern. That is, there is a concern that a third party posing as the reaction force control device 40 or the vehicle control device 60 may spoof the reaction force control device 40's turning on of the start permission signal S2 or the vehicle control device 60's turning on of the preparation completion signal S1. In this case, there is a risk that the vehicle will transition to a state in which it is capable of running before the reaction force control device 40 transitions to a state in which it is capable of executing reaction force control, that is, a waiting state for assist start. Therefore, the reaction force control device 40 is configured to execute the following process.

[0072] <Vehicle stop request determination process> The reaction force control device 40 executes a stop request determination process for the vehicle when the vehicle power supply is turned on. The stop request determination process is a process for determining whether or not it is necessary to request the vehicle control device 60 to stop starting the vehicle's powertrain. The stop request determination process is executed at a predetermined control period according to a program stored in the reaction force control device 40.

[0073] As shown in the flowchart of FIG. 6, the reaction force control device 40 determines whether or not it is necessary to request the vehicle control device 60 to stop starting of the vehicle's powertrain (step S201).

[0074] The reaction force control device 40 judges whether or not it is necessary to request the vehicle control device 60 to stop starting the vehicle's powertrain, based on whether a determined judgment condition is satisfied. The judgment condition is a condition for judging whether the ON of the start permission signal S2 by the reaction force control device 40 or the ON of the preparation completion signal S1 by the vehicle control device 60 is faked.

[0075] The judgment conditions include, for example, the following two conditions A1 and A2. When both of the two conditions A1 and A2 are satisfied, the reaction force control device 40 judges that it is necessary to request the vehicle control device 60 to stop the start of the vehicle's powertrain. Furthermore, when either one of the two conditions A1 and A2 is not satisfied, the reaction force control device 40 judges that it is not necessary to request the vehicle control device 60 to stop the start of the vehicle's powertrain.

[0076] A1. The start permission signal S2 is off. A2. The ready signal S1 is on. The judgment conditions are set based on the following viewpoint: For example, if the vehicle control device 60 turns on the preparation completion signal S1 even though the reaction force control device 40 has not turned on the start permission signal S2, there is a risk that the start permission signal S2 being turned on may have been spoofed by a third party masquerading as the reaction force control device 40.

[0077] When it is determined that it is necessary to request the vehicle control device 60 to stop the start-up of the vehicle's powertrain (YES in step S201), the reaction force control device 40 turns on the vehicle stop request signal S3 (step S202) and ends the processing.

[0078] When the reaction force control device 40 determines that there is no need to request the vehicle control device 60 to stop the startup of the vehicle's powertrain (NO in step S201), it turns off the vehicle stop request signal S3 (step S203) and ends the processing.

[0079] The vehicle stop request signal S3 is information indicating whether or not to request the vehicle control device 60 to stop the power drain operation. When the vehicle stop request signal S3 is on, it indicates that the vehicle control device 60 is requested to stop the power drain operation. When the vehicle stop request signal S3 is off, it indicates that the vehicle control device 60 is not requested to stop the power drain operation. The vehicle stop request signal S3 is transmitted to the vehicle control device 60 as an electrical signal.

[0080] <Second startup sequence pattern> Next, a second pattern of the start-up sequence will be described. As an example, a case will be considered in which the start permission signal S2 is falsely turned on during the midpoint learning process, which is one of the preparation processes performed by the reaction force control device 40. The start-up preparation of the vehicle control device 60 is completed before the midpoint learning process by the reaction force control device 40 is completed.

[0081] As shown in the time chart of FIG. 7, when the vehicle power supply is turned on (time T1), the reaction force control device 40 starts up and starts executing an initial check. After the initial check is normally completed, the reaction force control device 40 starts executing a midpoint learning process. For example, if the start permission signal S2 is falsely turned on during the execution of this midpoint learning process (time T7), the vehicle control device 60 recognizes that the start permission signal S2 is already on at the timing when the start preparation is completed, for example. Therefore, after the start preparation is completed, the vehicle control device 60 immediately starts the vehicle's powertrain without transitioning to a start permission waiting state. When the execution of the powertrain start process is completed, the vehicle control device 60 turns on the preparation completion signal S1 (time T8).

[0082] When the reaction force control device 40 recognizes that the preparation completion signal S1 is on even though the midpoint learning process is in progress, it turns on the vehicle stop request signal S3 (time T9). This is because there is a risk that the start permission signal S2 may be spoofed to be on by a third party masquerading as the reaction force control device 40.

[0083] After starting the powertrain of the vehicle, the vehicle control device 60 executes a predetermined process when it recognizes that the vehicle stop request signal S3 is on. The predetermined process is, for example, a process for stopping the operation of the powertrain. This puts the vehicle in a state in which it cannot run. In addition, it is prevented that the vehicle is maintained in a runnable state through fraudulent acts such as spoofing, even when the reaction force control device 40 is in the middle of executing the preparation process.

[0084] <About the remote function> However, when executing a stop request determination process for a vehicle, the following concerns arise. That is, the vehicle may have a remote function. The remote function is, for example, a function for remotely operating electronic devices mounted on a parked vehicle using wireless communication technology. A user of the vehicle can remotely operate functions of the vehicle, for example, through the operation of a mobile terminal carried by the user. The remote function is, for example, a remote air conditioner function. The remote air conditioner function allows the user to operate the air conditioner before getting into the vehicle, through remote operation using a mobile terminal. The air conditioner is an electronic device mounted on the vehicle.

[0085] When the remote function of the vehicle is turned on through the operation of the mobile terminal, that is, when a remote operation signal is received from the mobile terminal, the vehicle control device 60 turns on the vehicle power supply and starts execution of startup preparation. After the startup preparation is completed, the vehicle control device 60 starts the powertrain without the permission of the reaction force control device 40. When the execution of the powertrain start process is completed, the vehicle control device 60 operates the air conditioner. This allows the temperature in the vehicle cabin to be adjusted to an appropriate temperature before the user gets into the vehicle. In addition, when the execution of the powertrain start process is completed, the vehicle control device 60 turns on the preparation completion signal S1 regardless of the state of the reaction force control device 40. In other words, the vehicle control device 60 turns on the preparation completion signal S1 even if the start permission signal S2 is off.

[0086] Therefore, there is a risk that the vehicle control device 60 will turn on the preparation complete signal S1 before the preparation process of the reaction force control device 40 is completed, i.e., before the reaction force control device 40 turns on the start permission signal S2. In this case, even though the start permission signal S2 is not turned on, the reaction force control device 40 turns on the vehicle stop request signal S3 because the preparation complete signal S1 is turned on by the vehicle control device 60. When the vehicle control device 60 recognizes that the vehicle stop request signal S3 is on, it executes a process for stopping the operation of the powertrain. Therefore, there is a concern that the vehicle may be prohibited from running even though the remote function has been turned on by a legitimate user of the vehicle.

[0087] Therefore, the reaction force control device 40 is configured to execute a first stop request determination process or a second stop request determination process as a stop request determination process for the vehicle. The first stop request determination process and the second stop request determination process have different determination conditions. The determination conditions are conditions for determining whether the reaction force control device 40 needs to request the stop of the vehicle's powertrain. Whether the first stop request determination process or the second stop request determination process is adopted is determined by product specifications, etc.

[0088] <First stop request determination process> First, the first stop request determination process will be described. The first stop request determination process is basically executed according to the flowchart of Fig. 6. However, the determination conditions used in step S201 include the following condition A3 in addition to the two conditions A1 and A2.

[0089] A3. The vehicle's shift range must be within a range that allows driving. The shift range includes, for example, a parking range, a reverse range, a neutral range, and a drive range. The parking range is a shift range used when parking. The neutral range is a shift range in which power transmission between the drive source for driving the vehicle and the drive wheels is interrupted. The reverse range is a shift range used when moving the vehicle backward. The drive range is a shift range used when moving the vehicle forward. The parking range and the neutral range are shift ranges in which the vehicle cannot be driven by the power of the drive source for driving. The reverse range and the drive range are shift ranges in which the vehicle can be driven by the power of the drive source for driving.

[0090] The judgment conditions are set based on the viewpoint of allowing the preparation complete signal S1 to be turned on when the vehicle's remote function is turned on, while ensuring the function of stopping the vehicle's movement if the preparation complete signal S1 is turned on before the preparation processing of the reaction force control device 40 is completed.

[0091] The reaction force control device 40 executes the first stop request determination process according to the flowchart of Fig. 6. In step S201, the reaction force control device 40 determines whether it is necessary to stop the start of the vehicle's powertrain. When all three conditions A1, A2, and A3 are satisfied, the reaction force control device 40 determines that it is necessary to request the vehicle control device 60 to stop the powertrain. When at least one of the three conditions A1, A2, and A3 is not satisfied, the reaction force control device 40 determines that it is not necessary to request the vehicle control device 60 to stop the powertrain.

[0092] <Third startup sequence pattern> Next, a third pattern of the start-up sequence will be described. However, the vehicle power supply is turned off, and the shift range is the parking range.

[0093] As shown in the time chart of FIG. 8, when the remote function of the vehicle is turned on through the operation of the mobile terminal (time T11), the vehicle control device 60 turns on the vehicle power supply. The reaction force control device 40 starts when the vehicle power supply is turned on, and sequentially executes an initial check, a midpoint learning process, and a steering angle synchronization process. After starting up, the reaction force control device 40 acquires a shift range signal S4 from the vehicle control device 60 (T12). The shift range signal S4 is an electrical signal that indicates the current shift range.

[0094] When the vehicle power supply is turned on, the vehicle control device 60 starts preparation for starting the powertrain. After the startup preparation is completed, the vehicle control device 60 starts the powertrain and turns on the preparation complete signal S1 (T13). In the example of FIG. 8, for example, the preparation complete signal S1 is turned on while the midpoint learning process of the reaction force control device 40 is being executed. The preparation complete signal S1 is turned on due to the remote function being turned on.

[0095] Based on the shift range signal S4, the reaction force control device 40 recognizes that the shift range is in the parking position, i.e., the vehicle is in a state where it cannot run. Of the three conditions A1, A2, and A3, the reaction force control device 40 determines that it is not necessary to stop the powertrain because condition A3 is not satisfied. The reaction force control device 40 maintains the vehicle stop request signal S3 in an OFF state even if the preparation completion signal S1 turns ON during the execution of the midpoint learning process. This is because, for example, the vehicle is in a state where it cannot run, and therefore safety is ensured even before the preparation process of the reaction force control device 40 is completed.

[0096] Since the vehicle stop request signal S3 is not turned on, the powertrain is maintained in a started state. Therefore, the vehicle is prevented from being prohibited from running even if the remote function is turned on by a legitimate user of the vehicle. If the remote function is, for example, a remote air conditioner function, the user can get into the vehicle with the temperature inside the vehicle adjusted to an appropriate temperature and run the vehicle.

[0097] <Fourth startup sequence pattern> Next, a fourth pattern of the start-up sequence will be described. However, the power supply to the vehicle is turned off, the shift range is the parking range, and the remote function is turned off.

[0098] As shown in the time chart of Fig. 9, when the vehicle power supply is turned on (time T21), the reaction force control device 40 starts up and sequentially executes an initial check, a midpoint learning process, and a steering angle synchronization process. After starting up, the reaction force control device 40 acquires a shift range signal S4 from the vehicle control device 60 (time T22). The shift range signal S4 is an electrical signal that indicates the current shift range.

[0099] For example, when the ready signal S1 is turned on during the execution of the midpoint learning process (time T23), the reaction force control device 40 maintains the vehicle stop request signal S3 in the off state. However, the ready signal S1 is not a normal ready signal S1 in response to the start permission signal S2 that the reaction force control device 40 has turned on. The ready signal S1 is, for example, an abnormal ready signal S1 that has been counterfeited, or an abnormal ready signal S1 that the vehicle control device 60 has turned on at an incorrect timing.

[0100] Based on the shift range signal S4, the reaction force control device 40 recognizes that the shift range is in the parking position, that is, the vehicle is in a state where it cannot run. The reaction force control device 40 determines that it is not necessary to stop the powertrain because the condition A3 of the above three conditions A1, A2, and A3 is not satisfied. Therefore, even if the preparation completion signal S1 is turned on during the execution of the midpoint learning process, the reaction force control device 40 maintains the vehicle stop request signal S3 in an off state. This is based on the following viewpoint. That is, since the vehicle is in a state where it cannot run, safety is ensured even if the powertrain starts before the preparation process of the reaction force control device 40 is completed. In addition, since the vehicle is in a state where it cannot run, the possibility of theft, etc. occurring is low.

[0101] After completing the execution of the midpoint learning process, the reaction force control device 40 starts executing the steering angle synchronization process. For example, when the shift range is switched to the reverse range or the drive range during the execution of this steering angle synchronization process (time T24), the reaction force control device 40 executes the following process. That is, the reaction force control device 40 acquires the shift range signal S4 from the vehicle control device 60 (time T25), and recognizes that the shift range is a shift range in which the vehicle can travel based on the acquired shift range signal S4. The reaction force control device 40 determines that it is necessary to stop the powertrain when all of the above three conditions A1, A2, and A3 are satisfied, and turns on the vehicle stop request signal S3 (T26). This is based on the following viewpoint. That is, since the vehicle is in a state in which it can travel, it is not preferable for the vehicle to be in a state in which it can travel before the preparation process of the reaction force control device 40 is completed. Also, since the vehicle is in a state in which it can travel, the probability of theft or the like occurring increases.

[0102] When the vehicle stop request signal S3 is turned on after starting the powertrain of the vehicle, the vehicle control device 60 executes processing to stop the operation of the powertrain. This puts the vehicle in a state in which it cannot run. This prevents the vehicle from becoming in a runnable state before the preparation processing of the reaction force control device 40 is completed. In addition, it prevents the vehicle from being maintained in a runnable state through fraudulent acts such as spoofing, even when the reaction force control device 40 is in the middle of executing the preparation processing.

[0103] <Second stop request judgment process> Next, the second stop request determination process will be described. The first stop request determination process is basically executed according to the flowchart of Fig. 6. However, the determination conditions used in step S201 include the following condition A4 in addition to the two conditions A1 and A2.

[0104] A4.The remote function is turned off. The judgment conditions are set based on the viewpoint of allowing the preparation complete signal S1 to be turned on when the vehicle's remote function is turned on, while ensuring the function of stopping the vehicle's movement if the preparation complete signal S1 is turned on before the preparation processing of the reaction force control device 40 is completed.

[0105] The reaction force control device 40 executes the second stop request determination process according to the flowchart of Fig. 6. In step S201, the reaction force control device 40 determines whether it is necessary to stop the start of the vehicle's powertrain. When all of the three conditions A1, A2, and A4 are satisfied, the reaction force control device 40 determines that it is necessary to request the vehicle control device 60 to stop the powertrain. When at least one of the three conditions A1, A2, and A4 is not satisfied, the reaction force control device 40 determines that it is not necessary to request the vehicle control device 60 to stop the powertrain.

[0106] <The fifth startup sequence pattern> Next, a fifth pattern of the start-up sequence will be described, in which the power supply to the vehicle is turned off.

[0107] As shown in the time chart of FIG. 10, when the remote function of the vehicle is turned on through the operation of the mobile terminal (time T31), the vehicle control device 60 turns on the vehicle power supply. When the vehicle power supply is turned on, the reaction force control device 40 starts up and sequentially executes an initial check, a midpoint learning process, and a steering angle synchronization process. After starting up, the reaction force control device 40 acquires a remote signal S5 from the vehicle control device 60 (T32). The remote signal S5 is an electric signal that indicates whether the remote function is turned on.

[0108] When the vehicle power supply is turned on, the vehicle control device 60 starts preparation for starting the powertrain. After the startup preparation is completed, the vehicle control device 60 starts the powertrain and turns on the preparation complete signal S1 (time T33). In the example of FIG. 10, for example, the preparation complete signal S1 is turned on while the midpoint learning process of the reaction force control device 40 is being executed. The preparation complete signal S1 is turned on due to the remote function being turned on.

[0109] The reaction force control device 40 recognizes that the remote function is on based on the remote signal S5. When the remote function is on, the vehicle is basically in a state where it cannot run. The remote function is, for example, a remote air conditioner function, which is turned on when the vehicle is in a parked state. In the parked state, the shift range of the vehicle is maintained in the parking range.

[0110] The reaction force control device 40 determines that it is not necessary to stop the powertrain because the condition A4 of the above three conditions A1, A2, and A4 is not satisfied. Therefore, even if the preparation completion signal S1 is turned on during the execution of the midpoint learning process, the reaction force control device 40 maintains the vehicle stop request signal S3 in the off state. This is because, for example, the vehicle is in a state where it cannot run, and therefore safety is ensured even before the preparation process of the reaction force control device 40 is completed.

[0111] Since the vehicle stop request signal S3 is not turned on, the powertrain is maintained in a started state. Therefore, the vehicle is prevented from being prohibited from running even if the remote function is turned on by a legitimate user of the vehicle. If the remote function is, for example, a remote air conditioner function, the user can get into the vehicle with the temperature inside the vehicle adjusted to an appropriate temperature and run the vehicle.

[0112] <The sixth startup sequence pattern> Next, a sixth pattern of the start-up sequence will be described. However, the vehicle power supply is turned off and the remote function is turned off.

[0113] As shown in the time chart of Fig. 11, when the vehicle power supply is turned on (time T41), the reaction force control device 40 starts up and sequentially executes an initial check, a midpoint learning process, and a steering angle synchronization process. After starting up, the reaction force control device 40 acquires a remote signal S5 from the vehicle control device 60 (time T42). The remote signal S5 is an electric signal that indicates whether the remote function is turned on.

[0114] For example, when the ready signal S1 is turned on during the execution of the midpoint learning process (time T43), the reaction force control device 40 turns on the vehicle stop request signal S3 (T44). The ready signal S1 is not a normal ready signal S1 in response to the start permission signal S2 turned on by the reaction force control device 40. The ready signal S1 is, for example, an abnormal ready signal S1 that is counterfeited, or an abnormal ready signal S1 that the vehicle control device 60 turned on at an incorrect timing.

[0115] The reaction force control device 40 recognizes that the remote function is turned off based on the remote signal S5. Since all of the above three conditions A1, A2, and A4 are satisfied, the reaction force control device 40 determines that it is necessary to stop the powertrain. Therefore, the reaction force control device 40 turns on the vehicle stop request signal S3.

[0116] When the vehicle stop request signal S3 is turned on after starting the powertrain of the vehicle, the vehicle control device 60 executes processing to stop the operation of the powertrain. This puts the vehicle in a state in which it cannot run. This prevents the vehicle from becoming in a runnable state before the preparation processing of the reaction force control device 40 is completed. In addition, it prevents the vehicle from being maintained in a runnable state through fraudulent acts such as spoofing, even when the reaction force control device 40 is in the middle of executing the preparation processing.

[0117] <Effects of this embodiment> This embodiment provides the following advantages. (1) When the vehicle power supply is turned on, if information is exchanged between the reaction force control device 40 and the vehicle control device 60 in a manner that does not follow a predetermined pattern, the reaction force control device 40 requests the vehicle control device 60 to stop the vehicle from traveling. The exchange of information includes, for example, the vehicle control device 60 recognizing that the start permission signal S2 is on, and the reaction force control device 40 recognizing the preparation completion signal S1. The predetermined pattern includes, for example, the reaction force control device 40 turning on the start permission signal S2, and then the vehicle control device 60 turning on the preparation completion signal S1 in response to the start permission signal S2 being on. When this configuration is adopted, there is a concern that information exchanged between the reaction force control device 40 and the vehicle control device 60 may be falsified by some kind of fraudulent act. In addition, there is a concern that the vehicle control device 60 may turn on the preparation completion signal S1 at an incorrect timing for some reason. In this regard, according to the present embodiment, when information is exchanged between the reaction force control device 40 and the vehicle control device 60 in a manner that does not follow a predetermined pattern, the operation of the powertrain is stopped. Since the vehicle cannot run using the power of the drive source for running, crime prevention is further improved.

[0118] However, even if information is exchanged between the reaction force control device 40 and the vehicle control device 60 in a manner that does not follow a predetermined pattern, when the vehicle is not in a state in which it can be driven, the reaction force control device 40 does not request the vehicle control device 60 to stop the powertrain. Since the vehicle is not in a state in which it can be driven, it is possible to ensure safety and crime prevention.

[0119] (2) The reaction force control device 40 executes, for example, a first stop request determination process. In this case, the vehicle is not in a state in which it can run when the shift range of the vehicle is not a shift range in which it can run. Examples of shift ranges in which it is not possible to run include the parking range and the neutral range. When the shift range is the parking range or the neutral range, the vehicle cannot run using the power of the drive source for running. The shift range is a condition suitable for determining whether the vehicle is in a state in which it can run.

[0120] (3) The reaction force control device 40 executes, for example, a second stop request determination process. In this case, the vehicle is not in a state in which it can be driven when the remote function is on. The remote function is used, for example, when the vehicle is in a parked state. Therefore, when the remote function is on, the vehicle is in a parked state, that is, the vehicle cannot be driven by the power of the driving source for driving. The remote function being on is a suitable condition for determining whether the vehicle is in a state in which it can be driven.

[0121] (4) When the preparation process for reaction force control is completed, the reaction force control device 40 permits the vehicle control device 60 to start the powertrain. The permission given to the vehicle control device 60 is given, for example, by the reaction force control device 40 turning on the start permission signal S2. The vehicle control device 60 waits for the reaction force control device 40 to permit the powertrain to be started, and then starts the powertrain. For this reason, the vehicle can only travel after the preparation process for the reaction force control device 40 is completed. Therefore, the vehicle can start traveling in a safer state for the driver.

[0122] (5) When it is recognized that the powertrain has started even though the reaction force control device 40 has not permitted the vehicle control device 60 to start the powertrain, for example, the permission given to the vehicle control device 60 may have been forged by a fraudulent act such as impersonation. For example, the permission given to the vehicle control device 60 may be forged by forging the start permission signal S2 to be on. It may be recognized that the powertrain has started, for example, by the preparation completion signal S1 being on. According to this embodiment, when there is a possibility that the permission given to the vehicle control device 60 may have been forged, the reaction force control device 40 requests the vehicle control device 60 to stop the operation of the powertrain. The request to stop the operation of the powertrain is made, for example, by the reaction force control device 40 turning on the vehicle stop request signal S3. The vehicle control device 60 stops the operation of the powertrain in response to a request from the reaction force control device 40, thereby improving crime prevention.

[0123] (6) When the remote function is turned on, the vehicle control device 60 starts the powertrain without the permission of the reaction force control device 40. As a result, there is a risk that the reaction force control device 40 will request the vehicle control device 60 to stop the operation of the powertrain. However, if the vehicle is not in a state in which it can be driven, the reaction force control device 40 will not request the vehicle control device 60 to stop the operation of the powertrain even if the powertrain is started without the permission of the reaction force control device 40. As a result, the start of the powertrain accompanying the turning on of the remote function is permitted while still ensuring the function of stopping the operation of the powertrain when the powertrain is started without the permission of the reaction force control device 40. Therefore, user convenience is ensured.

[0124] (7) The preparation process of the reaction force control device 40 includes a midpoint learning process and a steering angle synchronization process. For example, if the vehicle starts traveling while the reaction force control device 40 is in the middle of performing the midpoint learning process or the steering angle synchronization process, the driver may have difficulty in steering the steering wheel 11 in the intended steering direction. This is because the steering wheel 11 automatically rotates during the midpoint learning process or the steering angle synchronization process. In this respect, according to the present embodiment, when the preparation process of the reaction force control is completed, the reaction force control device 40 permits the vehicle control device 60 to start the powertrain. Therefore, the vehicle can only travel after the preparation process of the reaction force control device 40 is completed. Therefore, the vehicle can start traveling in a safer state for the driver. The driver does not feel uncomfortable.

[0125] <Other embodiments> This embodiment may be modified as follows. The preparation complete signal S1, the start permission signal S2, the vehicle stop request signal S3, the shift range signal S4, and the remote signal S5 may be flags.

[0126] In the present embodiment, reaction force motor 21 and steering motor 31 have two systems of winding groups, but they may have one system of winding groups. In this case, reaction force control device 40 may have only one of first system circuit 41 and second system circuit 42. Also, in this case, steering control device 50 may have only one of first system circuit 51 and second system circuit 52. Note that first reaction force control circuit 41A or second reaction force control circuit 42A corresponds to a reaction force control circuit. First steering control circuit 51A or second steering control circuit 52A corresponds to a steering control circuit. [Explanation of symbols]

[0127] 11…Steering wheel 15…Steering wheel 21…Reaction motor 40...Reaction force control device (steering control device) 41A…First reaction force control circuit (control circuit) 42A...Second reaction force control circuit (control circuit) 60...Vehicle control device

Claims

1. a control circuit for controlling the drive of a reaction motor that generates a steering reaction force applied to a steering wheel whose power transmission is separated from that of the steered wheels of the vehicle; The control circuit is configured to request the vehicle control device to stop an operation of a power train including a drive source for driving the vehicle when information that does not follow a predetermined pattern is exchanged between the control circuit and a vehicle control device that controls driving of the vehicle when a vehicle power source is turned on, The steering control device is configured so that when the vehicle power supply is turned on and the vehicle is not in a state in which it can be driven, the control circuit does not request the vehicle control device to stop operation of the powertrain, even if information is exchanged between the vehicle control device and the control circuit in a manner that does not follow a predetermined pattern.

2. 2. The steering control device according to claim 1, wherein the vehicle is not in a state in which it can travel when the shift range of the vehicle is not a shift range in which it can travel.

3. The vehicle has a remote function for remotely operating an electronic device mounted on the vehicle in a parked state by using wireless communication technology, The steering control device according to claim 1 , wherein the remote function is turned on when the vehicle is not in a state in which the vehicle can be driven.

4. The steering control device according to any one of claims 1 to 3, wherein the control circuit is configured to permit the vehicle control device to start the powertrain when execution of a preparatory process that is executed in response to the vehicle power supply being turned on is completed, and when it is recognized via the vehicle control device that the powertrain has started, to transition to a normal control state in which reaction force control is executed to generate a steering reaction force in the reaction force motor.

5. The steering control device according to claim 4, wherein the control circuit is configured to request the vehicle control device to stop operation of the powertrain when it is recognized via the vehicle control device that the powertrain is started even though the vehicle control device has not been permitted to start the powertrain.

6. The vehicle has a remote function for remotely operating an electronic device mounted on the vehicle in a parked state by using wireless communication technology, The steering control device according to claim 5 , wherein the vehicle control device is configured to start the power train without permission of the control circuit when the remote function is turned on.

7. The preparation process includes a midpoint learning process for learning a neutral steering position of the steering wheel by moving the steering wheel to a first operating end and then moving the steering wheel in a reverse direction to a second operating end; 5. The steering control device according to claim 4, further comprising a steering angle synchronization process for correcting the rotational position of the steering wheel so that the rotational position of the steering wheel corresponds to the steered position of the steered wheels.

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