Steering system

Abstract

This steering system is provided with an operation device, a steering device, and a controller that is configured so as to have each of control states of a main control state, a sub control state, and a stopped state, and that shifts the control states among the main control state, the sub control state, and the stopped state. The steering system is further provided with a state transition permission means.

Description

Technical Field

[0001] The present disclosure relates to a steering system. Background Art

[0002] Conventionally, for example, a game device disclosed in Japanese Unexamined Patent Application Publication No. 2007-330312 is known. The conventional game device includes a terminal for inputting information corresponding to an operation amount of a steering wheel or the like for driving operation mounted on an actual vehicle capable of traveling, and generates an image displayed on a display and an effect sound output from a speaker based on the information corresponding to the operation amount of the steering wheel or the like input via the terminal, and executes a game based on the driving operation.

[0003] In the conventional game device, when a game start is instructed by a user, if the vehicle is in a non-travelable state, a game using the steering wheel is executed. In addition, in the steering system of the vehicle, when it is possible to switch between a main control state in which the steering wheel is turned to make the vehicle travel and a sub-control state in which the steering wheel is used to provide a game, it is necessary to maintain the safety of the vehicle more and consider the state transition of the control state. Summary of the Invention

[0004] The present disclosure provides a steering system capable of maintaining the safety of a vehicle when performing a state transition of a control state.

[0005] The steering system according to the technical solution of the present disclosure includes: an operation device configured to have an operation member and generate and apply a reaction force to the operation of the operation member; a steering device configured to release a mechanical connection with the operation device to turn a steering wheel of the vehicle; and a controller configured to implement a steering operation of the steering wheel performed by the steering device corresponding to the operation of the operation member, the controller being configured to: have a main control state for controlling the operation device and the steering device in such a manner that the operation of the operation member is synchronized with the steering operation, a sub-control state for controlling at least the operation device in such a manner that the operation of the operation member is not synchronized with the steering operation, and a stop state for stopping the operation of the operation device and the steering device, and perform a state transition between the main control state, the sub-control state, and the stop state, and the steering system further includes a state transition permission unit configured to: determine whether or not a specified state transition condition associated with the safety of the vehicle is satisfied when performing a state transition, and permit the state transition when the state transition condition is satisfied.

[0006] It may also be configured that: based on the technical solution of the present disclosure, the state transition condition includes at least a vehicle-related condition associated with the state of the vehicle.

[0007] It can also be configured as: on the basis of the technical solution of the present disclosure, the vehicle-related condition includes a condition for determining at least one of the parking state of the vehicle, the communication state through the communication line built in the vehicle, the working state of the operating device, and the working state of the steering device.

[0008] It can also be configured as: on the basis of the technical solution of the present disclosure, in the case where the vehicle is an electric vehicle that needs to charge the battery for driving the electric motor, the vehicle-related condition includes a condition for judging the charging state of the battery.

[0009] It can also be configured as: on the basis of the technical solution of the present disclosure, the state transition condition includes an authentication condition for authenticating a specific user who can instruct the controller to execute the state transition.

[0010] It can also be configured as: on the basis of the technical solution of the present disclosure, the authentication condition includes a manager authentication condition for authenticating a manager who manages the vehicle among specific users.

[0011] It can also be configured as: on the basis of the technical solution of the present disclosure, the authentication condition includes a licensed user authentication condition for authenticating a licensed user among specific users permitted by the manager.

[0012] It can also be configured as: on the basis of the technical solution of the present disclosure, the state transition condition includes a stop condition for stopping the operation of the operating device in the sub-control state.

[0013] It can also be configured as: on the basis of the technical solution of the present disclosure, the stop condition includes an abnormality determination condition for determining that an abnormality has occurred in the state of the vehicle.

[0014] It can also be configured as: on the basis of the technical solution of the present disclosure, the stop condition includes a cut-off determination condition for determining that the power supply of the vehicle has been cut off.

[0015] It can also be configured as: on the basis of the technical solution of the present disclosure, when determining whether to permit a state transition, in addition to determining whether the state transition condition is satisfied, the state transition permission unit also determines whether the system constituting the vehicle is normal.

[0016] It can also be configured as, on the basis of the technical solution of the present disclosure, the vehicle is an electric vehicle that needs to charge the battery for driving the electric motor, and the controller is configured to: during the charging of the battery, when the state transition is permitted by the state transition permission unit with the establishment of the state transition condition, execute the state transition from the main control state to the sub-control state.

[0017] Alternatively, based on the technical solution of the present disclosure, the controller is configured to: when performing a state transition from the sub-control state to the main control state according to the permission by the state transition permission unit, if there is a difference between the operation position of the operation member operated in the sub-control state and the steering position of the steering wheel accompanying the steering operation, perform alignment control to make the operation position consistent with the steering position.

[0018] Alternatively, based on the technical solution of the present disclosure, the controller is configured to: in the alignment control, operate the operating device to generate a reaction force with respect to the operation member, thereby making the operation position consistent with the steering position.

[0019] Alternatively, based on the technical solution of the present disclosure, the controller is configured to: in the sub-control state, provide entertainment using the operation member in the vehicle.

[0020] Alternatively, it can be configured that: based on the technical solution of the present disclosure, the entertainment is a game that instructs the movement of a virtual moving body by operating a device mounted on a vehicle including the operation member.

[0021] According to the technical solution of the present disclosure, when the state transition permission unit determines that the state transition condition is satisfied and permits the state transition, the steering system can change the control state of the controller. Thus, when performing a state transition between the main control state and the sub-control state, the steering system can maintain the safety of the vehicle.

[0022] Hereinafter, with reference to the accompanying drawings, the features, advantages, and technical and industrial significance of the exemplary embodiments of the present invention will be described. In the drawings, the same reference numerals denote the same elements. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic structural diagram of a vehicle.

[0024] Figure 2 is a functional block diagram of the state transition permission unit (state transition permission department).

[0025] Figure 3 is a diagram for explaining the state transition.

[0026] Figure 4 is for Figure 2 a diagram for explaining the processing performed by the authentication determination department.

[0027] Figure 5 is for Figure 2 a diagram for explaining the processing performed by the sub-control state transition permission determination department.

[0028] Figure 6is a diagram for explaining the processing performed by the sub-control state end determination unit of Figure 2 .

[0029] Figure 7 is a diagram for explaining the processing performed by the main control state transition permission determination unit of Figure 2 . DETAILED DESCRIPTION OF THE INVENTION

[0030] Hereinafter, the steering system 10 as an embodiment of the present disclosure will be described in detail with reference to the accompanying drawings. In addition, the present disclosure can be implemented in various forms obtained by making various changes and improvements based on the knowledge of those skilled in the art in addition to the embodiments described below.

[0031] 1. Structure of Vehicle 1 to Which Steering System 10 is Applied

[0032] In the present embodiment, the steering system 10 is applied to Figure 1 the vehicle 1 shown. The vehicle 1 includes a vehicle body 2, wheels 3 respectively arranged at the front, rear, left, and right, and a suspension unit 4 that supports the vehicle body 2 and each wheel 3. The wheels 3 are composed of a right front wheel 31, a left front wheel 32, a right rear wheel 33, and a left rear wheel 34. The suspension unit 4 is an independent suspension type corresponding to each wheel 3. For example, it has a coil spring 41 and a hydraulic shock absorber 42. In addition, the suspension unit 4 may also be an air suspension unit including an air spring, for example.

[0033] In addition, the vehicle 1 includes a drive system 5 that generates and transmits the driving force required for traveling. The drive system 5 has a front motor 51 and a rear motor 52 that are electric motors. The front motor 51 transmits the rotation of the output shaft to the left and right front wheel axles 54R and 54L via a differential gear 53 (including a reduction gear), thereby driving the right front wheel 31 and the left front wheel 32. The rear motor 52 transmits the rotation of the output shaft to the left and right rear wheel axles 56R and 56L via a differential gear 55 (including a reduction gear), thereby driving the right rear wheel 33 and the left rear wheel 34. That is, in the present embodiment, the vehicle 1 is an example of a four-wheel drive electric vehicle (EV).

[0034] In addition, the drive system 5 has an inverter 57, a DC / DC converter 58, and a battery 59. Thus, by the energization control of the inverter 57, the front motor 51 and the rear motor 52 can be independently driven in the forward rotation in the forward direction of the vehicle 1 and the reverse rotation in the reverse direction of the vehicle 1.

[0035] In addition, the inverter 57 has a charging port (not shown). For example, it has a charging function of converting the alternating current supplied from a charging device into direct current and charging the battery 59 via the DC / DC converter 58. Also, the inverter 57, for example, also has a function of converting the alternating current generated by the rear motor 52 into direct current and charging the battery 59 via the DC / DC converter 58, that is, storing the regenerative energy.

[0036] The front motor 51 and the rear motor 52 are controlled by a drive electronic control unit 61 (hereinafter sometimes simply referred to as "drive ECU 61") of the braking drive controller 6. The drive ECU 61 is an electronic control unit (Electric Control Unit) having a microcomputer as its main part. The microcomputer has a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and various interfaces. In addition, in Figure 1 it, the drive ECU 61 is denoted as "P-ECU 61".

[0037] In addition, the CPU performs operations such as reading data, numerical calculations, and outputting calculation results by sequentially executing a prescribed program. The ROM stores programs, maps, etc. executed by the CPU. The RAM temporarily stores data, etc. The various interfaces are connected to the communication line L. In addition, as the communication line L, for example, CAN (Car Area Network or Controllable Area Network), a dedicated communication line other than CAN can be exemplified.

[0038] The drive ECU 61 inputs the detection signal Sa of the accelerator sensor 71 that detects the accelerator operation amount in the sensor group 7, and calculates the driver-requested driving force corresponding to the accelerator operation amount. Then, the drive ECU 61 controls the front motor 51 and the rear motor 52 so that the front-wheel target driving force and the rear-wheel target driving force, which are the driver-requested driving force calculated and distributed to the front-wheel side and the rear-wheel side, are respectively transmitted to the right front wheel 31, the left front wheel 32, the right rear wheel 33, and the left rear wheel 34.

[0039] In addition, the drive ECU 61 inputs, for example, the detection signal Smf output from the control sensor 72 of the front motor 51, controls the operation of the inverter 57, and controls the energization of the front motor 51. Similarly, the drive ECU 61 inputs the detection signal Smr output from the control sensor 73 of the rear motor 52, controls the operation of the inverter 57, and controls the energization of the rear motor 52.

[0040] Further, the drive ECU 61 obtains the operation positions of a shift lever, a shift switch, etc., not shown, which are operated when the vehicle 1 moves forward, backward, or parks. Therefore, the drive ECU 61 inputs a detection signal Ssp indicating the operation position output from the shift position sensor 74 in the sensor group 7.

[0041] In addition, the vehicle 1 is equipped with a braking system 8 that generates the braking force required for braking. The braking system 8 includes a right front wheel brake 81, a left front wheel brake 82, a right rear wheel brake 83, a left rear wheel brake 84, and a brake actuator 85. Further, in Figure 1 the brake actuator 85 is denoted as "B / A85".

[0042] The right front wheel brake 81, the left front wheel brake 82, the right rear wheel brake 83, and the left rear wheel brake 84 are each not shown, but include a brake disc that rotates integrally with the wheel 3, a pair of brake pads that squeeze the brake disc from both sides, and a brake caliper that fixes the brake pads. In the brake caliper, the brake actuator 85 is connected via a brake pipe not shown, and a hydraulic circuit for working oil is formed between each of the right front wheel brake 81, the left front wheel brake 82, the right rear wheel brake 83, and the left rear wheel brake 84 and the brake actuator 85. Thus, in the braking system 8, when the brake actuator 85 pressurizes the working oil, the brake pads squeeze the brake disc, and as a result, frictional force, i.e., braking force, is generated.

[0043] The brake actuator 85 is configured to include a storage tank that stores the working oil and a master cylinder, a pump, etc. that pressurize the working oil. Further, the storage tank, the master cylinder, and the pump are not shown. The control of the brake actuator 85 is executed by the brake electronic control unit 62 (hereinafter, sometimes simply referred to as "brake ECU 62") that constitutes the brake drive controller 6. That is, the brake actuator 85 adjusts the pressure of the working oil respectively applied to the right front wheel brake 81, the left front wheel brake 82, the right rear wheel brake 83, and the left rear wheel brake 84 according to the control by the brake ECU 62. Thus, the brake actuator 85 can cause the right front wheel brake 81, the left front wheel brake 82, the right rear wheel brake 83, and the left rear wheel brake 84 to generate braking force respectively.

[0044] The brake ECU 62 is an electronic control unit (Electric Control Unit) having a microcomputer as the main part, and the microcomputer has a CPU, a ROM, a RAM, and various interfaces. The brake ECU 62 is connected to the communication line L via various interfaces. Further, in Figure 1 the brake ECU 62 is denoted as "B-ECU62".

[0045] The braking ECU 62 is connected to a hydraulic sensor (not shown), various control valves, a pump, etc. provided in the brake actuator 85. In addition, the braking ECU 62 is connected to the braking sensor 75 in the sensor group 7 that detects the driver's braking operation amount based on the depression amount of the brake pedal (not shown), the four wheel speed sensors 76 that respectively detect the wheel speeds of the individual wheels 3, and the parking brake sensor 77. Further, the four wheel speed sensors 76 respectively output a detection signal Swv1 indicating the wheel speed of the right front wheel 31, a detection signal Swv2 indicating the wheel speed of the left front wheel 32, a detection signal Swv3 indicating the wheel speed of the right rear wheel 33, and a detection signal Swv4 indicating the wheel speed of the left rear wheel 34.

[0046] The braking ECU 62 inputs the detection signal Sb of the braking sensor 75 to calculate the driver's required braking force corresponding to the braking operation amount. Moreover, the braking ECU 62 calculates the frictional braking forces respectively generated by the right front wheel brake 81, the left front wheel brake 82, the right rear wheel brake 83, and the left rear wheel brake 84, and the regenerative braking force generated by the rear motor 52 so as to achieve the driver's required braking force.

[0047] Here, the braking ECU 62 controls the operation of the brake actuator 85 based on the detection signals Swv1, Swv2, Swv3, Swv4 of the respective wheel speed sensors 76 so as to generate the calculated frictional braking force. Thereby, the brake actuator 85 pressurizes the working oil and supplies it to the right front wheel brake 81, the left front wheel brake 82, the right rear wheel brake 83, and the left rear wheel brake 84 respectively. Thereby, in each of the right front wheel brake 81, the left front wheel brake 82, the right rear wheel brake 83, and the left rear wheel brake 84, the brake pads press the brake discs to apply braking force to the respective wheels 3.

[0048] In addition, the braking ECU 62 sends information indicating the calculated regenerative braking force to the drive ECU 61. Thereby, when a regenerative brake command sent from the braking ECU 62 is input, the drive ECU 61 outputs a control signal generated in such a way as to apply the requested regenerative braking force to the right rear wheel 33 and the left rear wheel 34 to the inverter 57. Thereby, the duty ratio of the switching elements of the inverter 57 is controlled so that a current corresponding to the regenerative braking force flows from the rear motor 52 through the DC / DC converter 58 to the battery 59 to apply braking force to the right rear wheel 33 and the left rear wheel 34.

[0049] Further, the braking ECU 62 operates a known parking brake device (not shown) based on the detection signals Swv1, Swv2, Swv3, and Swv4 from the respective wheel speed sensors 76 when the vehicle 1 is in a stopped state. Moreover, when the braking ECU 62 operates the parking brake device and applies a braking force to the wheels 3 (for example, the right rear wheel 33 and the left rear wheel 34), the detection signal Spb output from the parking brake sensor 77 and indicating the state in which the parking brake device is applying a braking force is input.

[0050] 2. Structure of the steering system 10

[0051] In the present embodiment, the above-described steering system 10 mounted on the vehicle 1 steers the right front wheel 31 and the left front wheel 32 as steered wheels. Moreover, the steering system 10 is a steer-by-wire type including an operation device 11 and a steering device 12 that are mechanically independent of each other.

[0052] The operation device 11 mainly includes a steering wheel 111, a steering shaft 112, a steering column 113, and a reaction force applying mechanism 114. The steering wheel 111 is an operation member that is operated (steering operation) by a manager (i.e., a driver) authenticated as described later and a permitted user authenticated as described later. The steering shaft 112 has the steering wheel 111 mounted at its front end and is supported by the steering column 113 so as to be rotatable. The steering column 113 is supported by an instrument panel reinforcement (not shown).

[0053] The reaction force applying mechanism 114 uses a reaction force motor 115 as a driving force source and applies a reaction force Fc (strictly speaking, "reaction torque", but hereinafter referred to as "operation reaction force Fc") with respect to the steering operation to the steering wheel 111 via the steering shaft 112. The reaction force motor 115 can be exemplified by, for example, a three-phase brushless DC motor. Here, the reaction force motor 115 has a motor rotation angle sensor 116 that detects the motor rotation angle ω within one rotation in order to switch the energized phase when supplying power to itself. In addition, since the reaction force applying mechanism 114 has a general structure including a speed reducer and the like, the description of the specific structure is omitted.

[0054] In addition, the operation device 11 has an operation angle sensor 117 that detects the operation angle δ indicating the operation position of the steering wheel 111. Here, when the position adopted by the steering wheel 111 in the forward state of the vehicle 1 is set as the neutral position, the rotation angles in the left and right directions from the neutral position are the operation angle δ of the steering wheel 111.

[0055] In addition, the operation device 11 is the same as a so-called general power steering system and has a torsion bar 118 assembled to the steering shaft 112. Moreover, the operation device 11 has an operation torque sensor 119 that detects an operation torque To, which is an operation force applied by the driver to the steering wheel 111, based on the amount of twist of the torsion bar 118.

[0056] The steering device 12 turns the knuckles 43 constituting the suspension unit 4, thereby integrally steering the right front wheel 31 and the left front wheel 32 that are steerably supported by the vehicle body 2, respectively. The steering device 12 has a steering actuator 121 as a main component.

[0057] The steering actuator 121 mainly includes a steering rod 122, a housing 123, and a rod moving mechanism 124. Both ends of the steering rod 122 are connected to the left and right knuckles 43 via tie rods 125, respectively. The housing 123 is fixed to the vehicle body 2 and supports the steering rod 122 so as to be movable in the left-right direction.

[0058] The rod moving mechanism 124 moves the steering rod 122 in the left-right direction using the steering motor 126 as a driving force source. For example, a case where the rod moving mechanism 124 includes a ball screw mechanism as a main body can be exemplified. The ball screw mechanism is composed of a ball groove (not shown) provided in the steering rod 122 and a nut (not shown) that is screwed to the ball groove via bearing balls (not shown) and rotates by the steering motor 126.

[0059] In addition, since the ball screw mechanism is a general structure, a description of the specific structure of the rod moving mechanism 124 is omitted. In addition, the structure of the rod moving mechanism 124 is not limited to the ball screw mechanism, and other mechanisms can also be used.

[0060] Here, the steering motor 126 is the same as the reaction force motor 115. For example, a three-phase brushless DC motor can also be exemplified. Moreover, in order to switch the energized phase during power supply to itself, the steering motor 126 also independently has a motor rotation angle sensor 127 that detects the motor rotation angle ν within one rotation. In addition, the steering motor 126 independently has a current sensor 128 for detecting the current I actually supplied to itself (hereinafter, sometimes referred to as "steering current I").

[0061] In addition, the steering device 12 has a steering angle sensor 129 that detects a steering angle θ indicating the steering positions of the right front wheel 31 and the left front wheel 32 as steering wheels. Here, when the position of the steering rod 122 in the forward state of the vehicle 1 is set as the neutral position, the amount of movement in the left and right directions from the neutral position is the steering angle θ of the right front wheel 31 and the left front wheel 32.

[0062] The operation electronic control unit 13 (hereinafter sometimes simply referred to as "operation ECU 13") controls the operation device 11. More specifically, it controls the operation reaction force Fc, that is, controls the reaction force motor 115 of the operation device 11. The operation ECU 13 is an electronic control unit (Electric Control Unit) mainly composed of a microcomputer. The above-mentioned microcomputer has a CPU, a ROM, a RAM, and various interfaces. The operation ECU 13 is connected to the communication line L via various interfaces. In addition, in Figure 1 the operation ECU 13 is represented as "O-ECU 53".

[0063] The steering electronic control unit 14 (hereinafter sometimes simply referred to as "steering ECU 14") controls the steering device 12. More specifically, it controls the steering angle θ, that is, controls the steering motor 126 of the steering device 12. The steering ECU 14 is an electronic control unit (Electric Control Unit) mainly composed of a microcomputer. The above-mentioned microcomputer has a CPU, a ROM, a RAM, and various interfaces. The steering ECU 14 is connected to the communication line L via various interfaces. In addition, in Figure 1 the steering ECU 14 is represented as "S-ECU 14".

[0064] Here, for the control of the steering system 10, the steering control as the control of the steering device 12 and the reaction force control as the control of the reaction force applying mechanism 114 of the operation device 11 will be described. First, the steering control will be described. The steering control is for steering the right front wheel 31 and the left front wheel 32 according to a steering request, that is, according to the operation angle δ of the steering wheel 111 in the case of manual driving by the driver. The steering control is executed by the cooperation of the operation ECU 13 and the steering ECU 14 in the main control state as described later.

[0065] In the steering system 10, the motor rotation angle ω of the reaction force motor 115 of the operation device 11 and the operation angle δ of the steering wheel 111 have a relationship with a prescribed transmission ratio. Therefore, the operation ECU 13 obtains the operation angle δ based on the motor rotation angle ω detected via the motor rotation angle sensor 116. Then, the steering ECU 14 obtains the information of the operation angle δ from the operation ECU 13, and multiplies it by the steering gear ratio Rg set for the obtained operation angle δ, thereby determining the target steering angle θd which is the target of the steering angles θ of the right front wheel 31 and the left front wheel 32.

[0066] θd = Rg × δ... Equation (1)

[0067] In the steering system 10, instead of the steering angle θ, the motor rotation angle ν is used to control the steering angle θ of the right front wheel 31 and the left front wheel 32. Therefore, the steering ECU 14 determines the target motor rotation angle νd, which is the target of the motor rotation angle ν of the steering motor 126, based on the target steering angle θd determined according to the above formula (1). Moreover, the steering ECU 14 detects the actual motor rotation angle ν of the steering motor 126 via the motor rotation angle sensor 127, and determines the deviation of the motor rotation angle ν from the target motor rotation angle νd, that is, the motor rotation angle deviation Δν, according to the following formula (2).

[0068] Δν = νd - ν... Formula (2)

[0069] Here, in the steering system 10, the steering ECU 14 determines the torque Ts (hereinafter referred to as "steering torque Ts") that the steering motor 126 should generate according to the feedback control rule based on the motor rotation angle deviation Δν. That is, the steering ECU 14 determines the steering torque Ts according to the following formula (3).

[0070] Ts = Gp×Δν + Gi×∫Δνdt + Gd×dΔν / dt... Formula (3)

[0071] Among them, in the above formula (3), the first term is the proportional term, the second term is the integral term, and the third term is the differential term. In addition, in the above formula (3), Gp represents the proportional term gain, Gi represents the integral term gain, and Gd represents the differential term gain.

[0072] In the steering control, the steering ECU 14 supplies the steering current I corresponding to the steering torque Ts determined according to the above formula (3) to the steering motor 126. Here, the steering current I is generally in a proportional relationship with the steering torque Ts. Therefore, the steering ECU 14 determines the steering current I to be supplied to the steering motor 126 based on the determined steering torque Ts according to the proportional relationship, for example. Moreover, the steering ECU 14 supplies the steering current I to the steering motor 126 via an inverter (not shown) for example, thereby operating the steering motor 126 and steering the wheels 3, that is, the right front wheel 31 and the left front wheel 32, until the target steering angle θd is reached.

[0073] The reaction force control is to give the driver a sense of operation for the steering operation by applying an operation reaction force Fc to the steering wheel 111. The operation ECU 13 in the main control state and the sub-control state described later executes the reaction force control. Specifically, the operation ECU 13 determines the operation reaction force Fc according to the following formula (4) using the steering load basis component Fs and the operation force basis reduction component Fa as two components.

[0074] Fc = Fs - Fa... Formula (4)

[0075] Here, the steering load dependent component Fs in the above formula (4) is a component related to the steering force (the steering torque Ts of the steering motor 126) required to steer the right front wheel 31 and the left front wheel 32, and is determined based on the steering current I supplied to the steering motor 126. Although detailed explanations are omitted, the larger the steering current I, the greater the steering load of the right front wheel 31 and the left front wheel 32 is recognized, and the steering load dependent component Fs is determined to be a large value. In addition, in the main control state, information related to the steering current I actually supplied to the steering motor 126 is supplied from the steering ECU 14 to the operation ECU 13 via the communication line L. Further, in the sub-control state, for example, information related to the steering current I is generated by the operation ECU 13 based on a preset relationship or the like.

[0076] In addition, the operating force dependent reduction component Fa in the above formula (4) is, for example, a component for giving the driver the operating feeling in the conventional power steering system. In the conventional power steering system, generally, for example, an auxiliary torque corresponding to the operating torque To is generated by an electric motor and applied to the steering shaft 112.

[0077] Therefore, the operating force dependent reduction component Fa is determined according to the following formula (5) so as to reproduce the auxiliary torque. And the operation ECU 13 acquires the operating torque To via the operating torque sensor 119.

[0078] Fa = β × To … Formula (5)

[0079] Here, β in the above formula (5) represents a gain for determining the operating force dependent reduction component Fa.

[0080] The operation ECU 13 determines the current supplied to the reaction force motor 115, that is, the reaction force current Ic, according to the following formula (6) based on the operating reaction force Fc determined according to the above formula (4). And the operation ECU 13 supplies the determined reaction force current Ic to the reaction force motor 115.

[0081] Ic = α × Fc … Formula (6)

[0082] Here, α in the above formula (6) represents a preset power determination coefficient.

[0083] 3. Structure of the state transition permission unit 15

[0084] As described above, the operation ECU 13 as a controller can implement the main control state, that is, according to the operation of the steering wheel 111 as an operation member, in cooperation with the steering ECU 14 as a controller, thereby controlling the steering actions of the right front wheel 31 and the left front wheel 32 as steering wheels. On the other hand, for example, during the charging of the battery 59 mounted on the vehicle 1 as described later, the operation ECU 13 can perform a state transition to the sub-control state, that is, different from the main control state, it controls the operation of the steering wheel 111 in a state where the synchronization with the right front wheel 31 and the left front wheel 32 is released.

[0085] Here, as the main control state, for example, the following control state can be exemplified, that is, when the vehicle 1 is traveling, the operation device 11 cooperates with the steering device 12, and according to the operation angle δ of the steering wheel 111, the right front wheel 31 and the left front wheel 32 are synchronously steered so as to become the steering angle θ. In addition, as the sub-control state, for example, the following control state can be exemplified, that is, when the battery 59 is being charged and the vehicle 1 is parked (in a parked state), the synchronization between the operation device 11 and the steering device 12 is released, that is, the operation device 11 is prohibited from cooperating with the steering device 12 to steer the right front wheel 31 and the left front wheel 32.

[0086] Thus, in the sub-control state, when the steering wheel 111 is operated, the operation ECU 13 applies an operation reaction force Fc to the operation of the steering wheel 111 via the operation device 11, but the steering ECU 14 does not operate the steering device 12, and as a result, the right front wheel 31 and the left front wheel 32 are not steered. That is, in the sub-control state, the operation device 11 can be made independent of the steering device 12. Therefore, in the sub-control state, it is possible to provide entertainment mainly in the form of games for the occupants of the vehicle 1, that is, the manager or the authorized user as a specific user described later, such as indicating and controlling the movement of a virtual vehicle, a virtual aircraft, etc. as a virtual moving body using the steering wheel 111 during the charging of the battery 59.

[0087] In addition, the main control state is a control state in which the right front wheel 31 and the left front wheel 32 are appropriately steered when the vehicle 1 is traveling. Therefore, of course, it is more important than the sub-control state that can provide entertainment and should be given priority. Therefore, it is particularly important that the state transition cannot be simply made from the main control state to the sub-control state, and the state transition should be safely made from the sub-control state to the main control state. Therefore, when performing a state transition between the main control state and the sub-control state, it is necessary to determine the pre-set state transition conditions associated with the safety of the vehicle 1, and when the state transition conditions are satisfied, the state transition is permitted.

[0088] Therefore, the steering system 10 mounted on the vehicle 1 includes a state transition permission unit 15 as a state transition permission unit. The transition permission unit 15 determines the state transition conditions and permits the state transition when the state transition conditions are satisfied. In addition, in Figure 1 the state transition permission unit 15 is represented as "S / P-UNIT15".

[0089] Here, in the present embodiment, the state transition permission unit 15 is integrated with the operation ECU 13 as a controller. Therefore, the state transition permission unit 15 is also mainly composed of a microcomputer, and the microcomputer includes a CPU, a ROM, a RAM, and various interfaces. In addition, since the state transition permission unit 15 has a microcomputer as its main part, it can also be configured as a separate electronic control unit. Alternatively, the state transition permission unit 15 can be integrated with an ECU other than the operation ECU 13.

[0090] In addition, the state transition permission unit 15 can communicate with various ECUs such as the drive ECU 61, the brake ECU 62, and the steering ECU 14 via the communication line L, and can obtain detection values from various sensors such as the sensor group 7. The state transition permission unit 15 is connected to the authentication device 16, the input device 17, and the display device 18.

[0091] The state transition permission unit 15 determines the "state transition conditions" and permits the state transition between the main control state, the sub-control state, and the stop state. The "state transition conditions" include "vehicle-related conditions", "authentication conditions", and "stop conditions". Here, in the present embodiment, seven conditions are exemplified as the "vehicle-related conditions", two conditions are exemplified as the "authentication conditions", and two conditions are exemplified as the "stop conditions".

[0092] First, the vehicle-related conditions are conditions for determining the state of the vehicle 1, more specifically, for determining various states such as the vehicle speed, the vehicle speed state, the transmission state, the power transmission state, the steer-by-wire system state, the vehicle communication state, and the steering operation state, which indicate that the vehicle 1 is safely parked. That is, in the present embodiment, the vehicle-related conditions are composed of "vehicle-related condition 1", "vehicle-related condition 2", "vehicle-related condition 3", "vehicle-related condition 4", "vehicle-related condition 5", "vehicle-related condition 6", and "vehicle-related condition 7".

[0093] Specifically, the vehicle-related condition 1 is a condition for determining whether the vehicle speed is "0". Therefore, the vehicle-related condition 1 can be, for example, a condition for determining whether the vehicle speed calculated using the detection signals Swv1 to Swv4 of the wheel speed sensor 76 is "0". Additionally, as the vehicle-related condition 1, for example, it can also be a condition for determining whether braking force is applied by the parking brake based on the detection signal Spb of the parking brake sensor 77.

[0094] Furthermore, as the vehicle-related condition 1, conditions such as whether the acceleration operation amount is "0" (no acceleration operation) based on the detection signal Sa of the acceleration sensor 71 and whether the braking operation amount is not "0" (braking operation performed) based on the detection signal Sb of the brake sensor 75 can also be adopted. In this case, when determining the state transition, it is determined based on the detection signal Sa of the acceleration sensor 71 that the acceleration operation amount is "0", and based on the detection signal Sb of the brake sensor 75 that the braking operation amount is not "0". After the determination, it is not the case.

[0095] The vehicle-related condition 2 is a condition for determining the vehicle speed state, that is, whether the detection state of the vehicle speed is valid. Therefore, the vehicle-related condition 2 can be, for example, a condition for determining the performance of the wheel speed sensor 76, that is, the accuracy and output state of the detection signals Swv1 to Swv4 of the wheel speed sensor 76.

[0096] The vehicle-related condition 3 is a condition for determining the transmission state when the vehicle 1 is stopped. Therefore, the vehicle-related condition 3 is, for example, a condition for determining whether the driving force is not output from the front motor 51 and the rear motor 52 to the front wheel axles 54R, 54L and the rear wheel axles 56R, 56L via the differential gears 53 and 55, but rather the state where the wheels 3 are locked. Specifically, the vehicle-related condition 3 can take, for example, the detection signal Smf of the control sensor 72 and the detection signal Smr of the control sensor 73 being "0", and the detection signal Ssp of the shift position sensor 74 being in the "parking gear" as the condition.

[0097] The vehicle-related condition 4 is a condition for determining the power transmission state of the vehicle 1, that is, the states of the front motor 51, the rear motor 52, the inverter 57, the DC / DC converter 58, and the battery 59. Therefore, the vehicle-related condition 4 is, for example, a condition for determining whether it is "drive preparation completed" for the vehicle 1 to travel, or whether it is in a "charging state" where the battery 59 is being charged. Specifically, it can be a condition for determining whether the detection signal Smf of the control sensor 72 and the detection signal Smr of the control sensor 73 are "0", and whether the vehicle 1 is in a charging state where alternating current is supplied to the inverter 57 from the outside.

[0098] Vehicle-related condition 5 is a condition for determining the state of the steer-by-wire system of vehicle 1, that is, the operating state of the steering system 10 including the operating device 11 and the steering device 12. Therefore, vehicle-related condition 5 can be, for example, a condition for determining whether the detected values of the respective sensors such as the motor rotation angle sensor 116, the operating angle sensor 117, the operating torque sensor 119 provided on the operating device 11, and the motor rotation angle sensor 127, the current sensor 128, and the steering angle sensor 129 provided on the steering device 12 are appropriate.

[0099] Vehicle-related condition 6 is a condition for determining the state of the communication line L constructed in vehicle 1. Therefore, vehicle-related condition 6 can be, for example, a condition for determining whether the communication line L is normal based on the exchange of signals via the communication line L between the operation ECU 13, the steering ECU 14, the drive ECU 61, and the brake ECU 62.

[0100] Vehicle-related condition 7 is a condition for determining whether the steering wheel 111 as an operating member is in a non-operating state and whether the steering actuator 121 is in a non-steering state. Therefore, vehicle-related condition 7 can be, for example, a condition for determining whether the detected values of the operating angle sensor 117 and the operating torque sensor 119 are "0", and whether the detected values of the motor rotation angle sensor 127, the current sensor 128, and the steering angle sensor 129 are "0".

[0101] Next, the authentication condition is a condition including a "manager authentication condition" for authenticating the manager who manages vehicle 1 among the specific users who can board vehicle 1, and a "permitted user authentication condition" for authenticating the permitted users permitted by the manager among the specific users. The manager authentication condition is, for example, a key comparison condition for comparing the physical key (intelligent key, smartphone, etc.) corresponding to vehicle 1 on the side of the authentication device 16 of vehicle 1, and a biometric authentication condition for authenticating biometric information.

[0102] Specifically, the manager of vehicle 1 usually holds a physical key and operates the physical key when boarding vehicle 1. According to the above operation, the authentication device 16 compares the physical key. If the comparison is successful, for example, the door can be unlocked to board the vehicle. Therefore, whether it is possible to board vehicle 1 by operating the physical key can be adopted as the key comparison condition. In addition, the manager who boards the vehicle inputs biometric information such as an image of the face photographed by the authentication device 16 (or the input device 17), and fingerprints of the fingers obtained by contacting the authentication device 16 (or the input device 17). Thereby, the authentication device 16 authenticates the manager by performing a comparison with the biometric information of the specific user registered in advance.

[0103] In addition, the permission user authentication condition is, for example, a condition for authenticating the biometric information of a specific user who rides in the vehicle 1 with the administrator. Specifically, the permission user can be exemplified by, for example, the child of the administrator. Moreover, a specific user who rides in the vehicle 1 with the administrator inputs biometric information such as an image of the face captured by the authentication device 16 (or the input device 17), or a fingerprint of a finger obtained by contacting the authentication device 16 (or the input device 17). Thereby, the authentication device 16 authenticates the permission user by performing a comparison with the biometric information of the specific user registered in advance.

[0104] And, as will be described later, the stop condition is a condition for stopping the operation of the operation device 11 in the game mode that provides a game as entertainment in the sub-control state, that is, a condition for causing a state transition to the stop state. Moreover, the stop condition is a condition including an "abnormality determination condition" for determining that an abnormality has occurred in the state of the vehicle 1 and a "power-off determination condition" for determining that the power supply of the vehicle 1 has been cut off.

[0105] Specifically, the abnormality determination condition is a condition for determining whether at least one of the vehicle-related conditions 1 to 6 (excluding vehicle-related condition 7) and the authentication condition composed of the above vehicle-related conditions does not hold, or whether an abnormality has occurred in the vehicle 1. The power-off determination condition is a condition for determining whether the power supply of the vehicle 1 has been cut off, and is a condition for determining whether a start / stop switch, a power switch, an ignition switch, etc. provided in the vehicle 1 has been switched from the on state to the off state.

[0106] As Figure 2 shown, the state transition permission unit 15 includes an authentication determination unit 151, a sub-control state transition permission determination unit 152, a sub-control state end determination unit 153, and a main control state transition permission determination unit 154.

[0107] The authentication determination unit 151 authenticates a specific user who operates the steering wheel 111, specifically, the administrator and the permission user, when permitting a state transition between the main control state and the sub-control state. Therefore, the authentication determination unit 151 cooperates with the authentication device 16 (and the input device 17) to determine whether the above authentication conditions, that is, the administrator authentication condition and the permission user authentication condition, are satisfied. Thereby, the authentication determination unit 151 authenticates the administrator among the specific users, or authenticates the permission user. Moreover, the authentication determination unit 151 outputs the authentication result indicating that the administrator and / or the permission user has been appropriately authenticated to the sub-control state transition permission determination unit 152, the sub-control state end determination unit 153, and the main control state transition permission determination unit 154, respectively.

[0108] When a request for a state transition to the sub-control state is made, the sub-control state transition permission determination unit 152 determines whether to permit the state transition to the sub-control state. Specifically, in the case of causing the operation ECU 13 to transition from the main control state to the sub-control state, or in the case of causing the operation ECU 13 to transition to the sub-control state immediately after turning on the power of the vehicle 1, the sub-control state transition permission determination unit 152 determines whether each of the above seven vehicle-related conditions 1 to vehicle-related condition 7 is satisfied, and the authentication determination unit 151 determines whether there is an authentication result. Further, the sub-control state transition permission determination unit 152 determines whether the drive system 5, the braking system 8, and the steering system 10 of the vehicle 1 are normal. Moreover, on the basis that all of the seven vehicle-related conditions 1 to vehicle-related condition 7 are satisfied and an authentication result is obtained, and the vehicle 1 is normal, the sub-control state transition permission determination unit 152 permits the state transition to the sub-control state.

[0109] In the case of a situation where the sub-control state should be ended, the sub-control state end determination unit 153 determines whether the above stop conditions are satisfied. Specifically, the sub-control state end determination unit 153 preferentially determines whether the above abnormal determination conditions are satisfied. Thereby, when an abnormality occurs in the vehicle 1, the sub-control state end determination unit 153 cooperates with the operation ECU 13 and reports to the manager or the authorized user that the operation has ended due to the occurrence of the abnormality via the display device 18 (for example, AR (Augmented Reality) glasses, in-vehicle display, etc.). In addition, when an abnormality occurs in the vehicle 1, the sub-control state end determination unit 153 cooperates with the operation ECU 13, for example, gradually reduces the control amount of the reaction force applying mechanism 114 and ends the sub-control state.

[0110] Further, the sub-control state end determination unit 153 determines whether the above disconnection determination conditions are satisfied. Thereby, when the manager or the authorized user performs an end operation, for example, when the manager or the authorized user performs a power-off operation of the vehicle 1, the sub-control state end determination unit 153 cooperates with the operation ECU 13 in the same manner as the stop process during a normal power-off operation, for example, stops the operation of the reaction force applying mechanism 114 to end the sub-control state, and finally cuts off the power of the vehicle 1.

[0111] When a request for a state transition from the sub-control state to the main control state, that is, a restoration request is made, the main control state transition permission determination unit 154 determines whether to permit the state transition from the sub-control state to the main control state. Specifically, when causing the operation ECU 13 to transition from the sub-control state to the main control state, the main control state transition permission determination unit 154 determines whether each of the above seven vehicle-related conditions 1 to vehicle-related condition 7 is satisfied, and the authentication determination unit 151 determines whether there is an authentication result. Further, the sub-control state transition permission determination unit 152 determines whether the drive system 5, the braking system 8, and the steering system 10 of the vehicle 1 are normal. Moreover, when there is a restoration request, all of the seven vehicle-related conditions 1 to vehicle-related condition 7 are satisfied, an authentication result is obtained, and the vehicle 1 is normal, the sub-control state transition permission determination unit 152 permits the state transition from the sub-control state to the main control state. [[ID=1]] [[ID=2]]

[0112] [[ID=3]]In addition, when the state transition from the sub-control state to the main control state is permitted, the main control state transition permission determination unit 154 cooperates with the operation ECU 13. For example, the reaction force applying mechanism 114 is operated to rotate the steering wheel 111, thereby performing alignment control. As a result, the operation ECU 13 makes the operation angle δ of the steering wheel 111 coincide with the steering angle θ of the steered wheels, that is, the right front wheel 31 and the left front wheel 32, which are steered by the steering actuator 121 of the steering device 12. [[ID=4]] [[ID=5]]

[0113] [[ID=6]]4. Processing Contents of the State Transition Permission Unit 15 [[ID=7]] [[ID=8]]

[0114] [[ID=9]]Next, the processing performed by the state transition permission unit 15 will be specifically described. In the following description, an example is given in which the sub-control state is a "game mode" in which a game is provided for a manager or an authorized user for entertainment. [[ID=10]] [[ID=11]]

[0115] [[ID=12]]Here, in the present embodiment, as [[ID=13]] Figure 3 [[ID=14]]shown, four state transitions are exemplified. That is, in the present embodiment, the case of transitioning from the main control state to the game mode state as the sub-control state is defined as "state transition A", the case of directly transitioning to the game mode state after the initial inspection is completed, that is, immediately after turning on the power of the vehicle 1, is defined as "state transition B", the case of transitioning from the game mode state to the stop state is defined as "state transition C", and the case of transitioning from the game mode state to the main control state is defined as "state transition D". [[ID=15]] [[ID=16]]

[0116] [[ID=17]]4-1. State Transition A and State Transition B [[ID=18]] [[ID=19]]

[0117] [[ID=20]]As [[ID=21]] Figure 3 [[ID=22]]shown, state transition A is the case of transitioning to the game mode state after transitioning to the main control state after the initial inspection is completed. AsFigure 3 As shown, state transition B is a case where the state directly transitions to the game mode state after the initial check. In order to safely transition to the game mode state in either case of state transition A or state transition B, the state transition permission unit 15 performs the following processing.

[0118] That is, in state transitions A and B, as Figure 4 shown, for example, a specific user (administrator) who operates the physical key and gets in the vehicle inputs a state transition request to the game mode via the input device 17. Thereby, the authentication determination unit 151 of the state transition permission unit 15 cooperates with the authentication device 16 (and the input device 17) to authenticate the administrator and / or authorized users, and outputs an authentication result.

[0119] Moreover, in state transitions A and B, as Figure 5 shown, for example, the administrator or an authorized user inputs a state transition request via the input device 17. In the case where such a state transition request has been made, the sub-control state transition permission determination unit 152 of the state transition permission unit 15 determines whether to permit the state transition from the main control state to the game mode as the sub-control state. Specifically, when all of the seven vehicle-related conditions 1 to 7 are satisfied, an authentication result indicating that the administrator authentication condition and the authorized user authentication condition are satisfied is obtained, and the drive system 5, the braking system 8, and the steering system 10 of the vehicle 1 are normal, the sub-control state transition permission determination unit 152 permits the operation ECU 13 to transition to the game mode state. In addition, in the following description, the precondition that all of the seven vehicle-related conditions 1 to 7 are satisfied and an authentication result is obtained, that is, the precondition for permitting the state transition to the game mode through state transition A or state transition B, is referred to as the "game mode state transition precondition".

[0120] Here, when the state transition permission unit 15 permits the state transition to the game mode, first and foremost, it is important to maintain the safety of the vehicle 1. That is, it is particularly important to confirm that the vehicle 1 is maintained in a completely stopped and non-drivable state, that the drive system 5, the braking system 8, and the steering system 10 of the vehicle 1 are normal, and the reliability of the state transition request to the game mode.

[0121] Therefore, for the state transition permission unit 15, in a state where the drive system 5, the braking system 8, and the steering system 10 of the vehicle are driven normally through the initial inspection, the authentication determination unit 151 authenticates the manager and / or the authorized user after the input of a state transition request. Moreover, the state transition permission unit 15 determines that all of the seven vehicle-related conditions 1 to vehicle-related condition 7 are satisfied, that is, the vehicle 1 is safely parked and normal, on the premise that the authentication of the manager and / or the authorized user is successful, that is, the authentication result is obtained. Here, when an abnormality occurs in the drive system 5, the braking system 8, and the steering system 10 of the vehicle 1 during the initial inspection, as Figure 3 shown, the state transition permission unit 15 changes the state from the initial inspection to the stop state.

[0122] 4-2. State Transition C

[0123] As Figure 3 shown, state transition C is a case where the game mode abnormally ends and the state is changed from the game mode to the stop state by an end operation performed by the authenticated manager or authorized user. For the state transition permission unit 15, particularly in the case of an abnormal end, in order to prioritize the safe transition to the stop state, the following processing is performed.

[0124] That is, in state transition C, as Figure 6 shown, as a case where the transition to the stop state caused by the abnormal end is permitted, the sub-control state end determination unit 153 determines whether the abnormality determination condition is satisfied. Here, the sub-control state end determination unit 153 determines whether there is a condition that is not satisfied among the six vehicle-related conditions 1 to vehicle-related condition 6 that form the preconditions for the game mode state transition as the abnormality determination condition. In addition, in the game mode, the possibility of operating the steering wheel 111 is relatively high, so the "vehicle-related condition 7" including the non-operation state of the steering wheel 111 is excluded.

[0125] That is, this is a case where a part of the preconditions for the game mode state transition collapses. Therefore, when there is a condition that is not satisfied among the six vehicle-related conditions 1 to vehicle-related condition 6, the sub-control state end determination unit 153 determines the end of the game mode (sub-control state), thereby permitting the state transition of the operation ECU 13 from the game mode to the stop state.

[0126] In addition, in state transition C, as Figure 6As shown, in the case of permitting the state transition to the stop state caused by an abnormal end, it is determined whether an abnormality has occurred in the drive system 5, the braking system 8, and the steering system 10 of the vehicle 1. That is, this case is, for example, a case where an abnormality has occurred in the vehicle 1 such as an abnormality in the charging system including the battery 59 or an abnormality in the steering actuator 121 of the steering device 12. Therefore, when an abnormality has occurred in the vehicle 1, the sub-control state end determination unit 153 determines the end of the game mode (sub-control state), thereby permitting the state transition of the operation ECU 13 from the game mode to the stop state.

[0127] In addition, when an abnormality has occurred in the vehicle 1, the sub-control state end determination unit 153 cooperates with the operation ECU 13 to report to the manager or the authorized user via the display device 18 that the game has ended due to the occurrence of the abnormality. Further, when an abnormality has occurred in the vehicle 1, the sub-control state end determination unit 153 cooperates with the operation ECU 13 to stop the operation of the steering system 10.

[0128] And, in the state transition C, as Figure 6 shown, in the case of permitting the state transition to the stop state caused by the end operation, the sub-control state end determination unit 153 determines the cut-off determination condition. That is, the sub-control state end determination unit 153 determines whether the start / stop switch, power switch, ignition switch, etc. provided in the vehicle 1 have been switched from the on state to the off state as the end operation.

[0129] That is, this case is a case where the game mode is ended by the authenticated manager or authorized user cutting off the power supply of the vehicle 1. Therefore, when the power supply of the vehicle 1 has been cut off, the sub-control state end determination unit 153 determines the end of the game mode (sub-control state), thereby permitting the state transition of the operation ECU 13 from the game mode to the stop state. In addition, when the power supply of the vehicle 1 has been cut off, the sub-control state end determination unit 153 cooperates with the operation ECU 13 to stop the operation of the steering system 10 and finally cut off the power supply of the vehicle 1.

[0130] Here, in addition to the state transition to the stop state caused by the above-mentioned abnormal end and the state transition to the stop state caused by the end operation, when determining the state transition to the stop state for some reason, in the determination process of the sub-control state end determination unit 153 executed later, the previous determination result is maintained. Thereby, it is possible to prevent the state transition permission unit 15 from repeatedly determining the state transition to the stop state.

[0131] In addition, as Figure 3As shown, in the normal usage mode of the vehicle 1, when changing the state from the main control state to the stop state, the state transition permission unit 15 can also permit the state transition from the main control state to the stop state. That is, when the power supply of the vehicle 1 is cut off by an end operation in the main control state, the state transition permission unit 15 can permit the state transition to the stop state. In addition, when an end operation is performed, the power supply of the vehicle 1 is finally cut off. Further, when an abnormality occurs in the vehicle 1 in the main control state, the state transition permission unit 15 can report the occurrence of the abnormality via the display device 18 and permit the state transition to the stop state.

[0132] 4-3. State Transition D

[0133] As Figure 3 shown, the state transition D is the case of changing the state from the game mode to the main control state after the initial check is completed. The state transition permission unit 15 performs the following processing in order to safely exit the game mode and change the state to the main control state (recovery).

[0134] That is, in the state transition D, as Figure 7 shown, for example, the administrator or the authorized user inputs a recovery request (state transition request) to the main control state via the input device 17. When such a recovery request is made, the main control state transition permission determination unit 154 of the state transition permission unit 15 determines whether to permit the state transition from the game mode, which is the sub-control state, to the main control state. Specifically, when the preconditions for the state transition in the game mode are satisfied and the drive system 5, the braking system 8, and the steering system 10 of the vehicle 1 are normal, the main control state transition permission determination unit 154 permits the state transition of the operation ECU 13 from the game mode to the main control state.

[0135] That is, in order to safely change the state to the main control state (recovery), the state transition permission unit 15 permits the state transition from the game mode to the main control state only when there is a recovery request from the administrator or the authorized user, the preconditions for the state transition in the game mode are satisfied, and the vehicle 1 is normal. Therefore, for example, when the preconditions for the state transition in the game mode are not satisfied, or when an abnormality occurs in any one of the drive system 5, the braking system 8, and the steering system 10 of the vehicle 1 during the initial check, the state transition permission unit 15 gives priority to the above-mentioned state transition C and changes the state to the stop state.

[0136] In addition, in state transition D, even when the vehicle-related condition 7 is satisfied, that is, even when the steering wheel 111 is in a non-operated state, since the steering wheel 111 is operated in the game mode, a situation may occur in which the operation angle δ of the steering wheel 111 cannot be synchronized with the steering angles θ of the right front wheel 31 and the left front wheel 32. Therefore, in state transition D, alignment control is executed by performing an initial check for state transition from the game mode, thereby synchronizing the operation angle δ with the steering angle θ, and then, the state is transitioned to the main control state. In addition, since a precise initial check is performed after the power supply of the vehicle 1 is turned on, some of the check items can be omitted for the initial check performed in state transition D.

[0137] As can be seen from the above description, the steering system 10 includes: an operation device 11 having a steering wheel 111 as an operation member, generating and applying a reaction force, that is, an operation reaction force Fc, to the operation of the steering wheel 111; a steering device 12 that releases the mechanical connection with the operation device 11 to steer wheels 3 (right front wheel 31 and left front wheel 32) that are steering wheels of the vehicle 1; and an operation ECU 13 and a steering ECU 14 as controllers that implement a steering action of the wheels 3 performed by the steering device 12 corresponding to the operation of the steering wheel 111. The operation ECU 13 among the operation ECU 13 and the steering ECU 14 has a main control state in which the steering device 12 is controlled in cooperation with the operation device 11 and the steering ECU 14 in such a manner that the operation of the steering wheel 111 is synchronized with the steering action, a sub-control state in which at least the operation device 11 is controlled in such a manner that the operation of the steering wheel 111 is not synchronized with the steering action, and a stop state in which the operation of the steering device 12 is stopped in cooperation with the operation device 11 and the steering ECU 14, and can perform a state transition between the main control state, the sub-control state, and the stop state. The state transition permission unit 15 is provided as a state transition permission unit, and the state transition permission unit 15 is configured to: when performing a state transition, determine whether or not a specified state transition condition associated with the safety of the vehicle 1 is satisfied, and permit the state transition when the state transition condition is satisfied.

[0138] In this case, the state transition condition can at least include a vehicle-related condition associated with the state of the vehicle 1. In this case, the vehicle-related condition can include a condition for determining at least one of the parking state of the vehicle 1, the communication state through the communication line L constructed in the vehicle 1, the operating state of the operation device 11, and the operating state of the steering device 12. In this case, when the vehicle 1 is an electric vehicle that needs to charge a battery 59 for driving a front motor 51 and a rear motor 52 that are electric motors, the vehicle-related condition can include a condition for determining the charging state of the battery 59.

[0139] In addition, in this case, the state transition condition can include an authentication condition for authenticating a specific user who can instruct the operation ECU 13 to execute the state transition. In this case, the authentication condition can include a manager authentication condition for authenticating the manager of the managed vehicle 1 among the specific users. In this case, the authentication condition can include a permitted user authentication condition for authenticating a permitted user who is permitted by the manager among the specific users.

[0140] In addition, in this case, the state transition condition can include a stop condition for stopping the operation of the operating device 11 in the sub-control state. In this case, the stop condition can include an abnormality determination condition for determining that an abnormality has occurred in the state of the vehicle 1. In this case, the stop condition can include a disconnection determination condition for determining that the power supply of the vehicle 1 has been disconnected.

[0141] In addition, in this case, when determining whether to permit the state transition, the state transition permission unit 15 can determine whether the systems constituting the vehicle 1, namely, the drive system 5, the braking system 8, and the steering system 10, are normal, in addition to determining whether the state transition condition is satisfied.

[0142] In addition, in this case, the vehicle 1 is an electric vehicle that needs to charge the battery 59 for driving the front motor 51 and the rear motor 52. When the state transition is permitted by the state transition permission unit 15 with the state transition condition satisfied during the charging of the battery 59, the operation ECU 13 can execute the state transition from the main control state to the sub-control state.

[0143] In addition, in this case, when performing the state transition from the sub-control state to the main control state according to the permission by the state transition permission unit 15, when a difference occurs between the operation angle δ indicating the operation position of the steering wheel 111 operated in the sub-control state and the steering angle θ indicating the steering position of the right front wheel 31 and the left front wheel 32 accompanying the steering operation, the operation ECU 13 can execute alignment control to make the operation angle δ coincide with the steering angle θ. In this case, in the alignment control, the operation ECU 13 operates the operating device 11 to generate an operation reaction force Fc with respect to the steering wheel 111, thereby enabling the operation angle δ to coincide with the steering angle θ.

[0144] In addition, in this case, in the sub-control state, the operation ECU 13 can provide entertainment using the steering wheel 111 in the vehicle 1. In this case, the entertainment is a game that instructs the movement of a virtual moving body by operating the devices mounted on the vehicle 1 including the steering wheel 111.

[0145] According to the steering system 10, when the state transition permission unit 15 provided in the operation ECU 13 determines that the state transition condition is satisfied and permits the state transition, the control state of the operation ECU 13 can be changed. Specifically, when the state transition condition is satisfied and the state transition is permitted, the operation ECU 13 can change the control state among the main control state, the sub-control state, and the stop state. Thereby, especially when changing the state between the main control state and the sub-control state, the steering system 10 can maintain the safety of the vehicle 1.

[0146] In addition, when permitting the state transition, the state transition permission unit 15 can determine whether the drive system 5, the brake system 8, and the steering system 10 of the vehicle 1 are normal in addition to determining whether the state transition condition is satisfied. Thereby, especially when changing the state from the sub-control state to the main control state, it is possible to suppress the occurrence of abnormal conditions during the running of the vehicle 1, and further maintain the safety of the vehicle 1.

[0147] Moreover, according to the steering system 10, for example, when the vehicle 1 is an electric vehicle, when the state transition permission unit 15 permits the state transition to the sub-control state along with the satisfaction of the state transition condition during the charging of the battery 59, the operation ECU 13 can provide the execution of a game that is entertainment using the steering wheel 111 to the manager or the permitted user. In this case, the provision of the game is also realized based on the permission of the state transition permission unit 15, so the safety of the vehicle 1 can be maintained. Also, in this case, for example, even if the time required for charging the battery 59 becomes longer, the manager or the permitted user can enjoy the game while spending the charging time.

[0148] 5. Modification Example

[0149] In the above-described embodiment, the state transition permission unit 15 as the state transition permission unit is provided in the operation ECU 13 which is the controller of the steering system 10, and the state transition permission unit 15 permits the state transition of the control state in the operation ECU 13. In addition to this, for example, the state transition permission unit can also be provided in the drive ECU 61 and the brake ECU 62 that constitute the brake drive controller 6.

[0150] Thus, for example, as described above, when a game is provided as entertainment in the sub-control state, in addition to the steering wheel 111 of the steering system 10, the manager and the authorized user can also operate the accelerator pedal and the brake pedal while maintaining the safety of the vehicle. That is, in the drive ECU 61 and the brake ECU 62, when changing the state between the main control state and the sub-control state, the state change can also be considered in a manner that further maintains safety in the vehicle, thereby maintaining the safety of the vehicle. Therefore, in this case, the same effect as that of the above-described embodiment can also be obtained.

[0151] In addition, in the above-described embodiment, for example, the steering system 10 mounted on the vehicle 1 that travels by manual driving of the driver as the manager is illustrated. That is, the case of manually operating the steering wheel 111 in the main control state and the sub-control state is illustrated. Instead, it may be a steering system that is not operated by autonomous driving in the main control state but is manually operated when a game is provided as entertainment in the sub-control state. In this case, regardless of the difference between manual driving and autonomous driving, when changing the state between the main control state and the sub-control state, the safety of the vehicle 1 can also be maintained. Therefore, in this case, the same effect as that of the above-described embodiment can also be obtained.

[0152] Moreover, in the above-described embodiment, the case where the vehicle 1 is an electric vehicle (EV (Electric Vehicle)) having only an electric motor as a driving force source is illustrated. However, the vehicle 1 may, for example, also be a vehicle having an internal combustion engine and an electric motor as driving force sources (HEV (Hybrid Electric Vehicle), PHEV (Plug-in Hybrid Electric Vehicle), etc.), or a vehicle having only an internal combustion engine as a driving force source. In this case, the same effect as that of the above-described embodiment can also be obtained.

[0153] Here, the steering system according to the first aspect of the present disclosure includes: an operation device configured to have an operation member and generate and apply a reaction force to the operation of the operation member; a steering device configured to disconnect the mechanical connection with the operation device to steer the steering wheels of the vehicle; and a controller configured to implement the steering operation of the steering wheels based on the steering device corresponding to the operation of the operation member. The controller is configured to have a main control state for controlling the operation device and the steering device in a manner such that the operation of the operation member is synchronized with the steering operation, a sub-control state for controlling at least the operation device in a manner such that the operation of the operation member is not synchronized with the steering operation, and a stop state for stopping the operation of the operation device and the steering device, and to perform a state transition among the main control state, the sub-control state, and the stop state. The controller further includes a state transition permission unit configured to determine whether or not a specified state transition condition associated with the safety of the vehicle is satisfied when performing a state transition, and to permit the state transition when the state transition condition is satisfied.

[0154] In addition, the steering system according to the second aspect of the present disclosure is configured such that, based on the steering system according to the first aspect, the state transition condition includes at least a vehicle-related condition associated with the state of the vehicle.

[0155] In addition, the steering system according to the third aspect of the present disclosure is configured such that, based on the steering system according to the second aspect, the vehicle-related condition includes a condition for determining at least one of the parking state of the vehicle, the communication state via a communication line provided in the vehicle, the operating state of the operation device, and the operating state of the steering device.

[0156] In addition, the steering system according to the fourth aspect of the present disclosure is configured such that, based on the steering system according to the first aspect or the second aspect, when the vehicle is an electric vehicle that needs to charge a battery for driving an electric motor, the vehicle-related condition includes a condition for determining the charging state of the battery.

[0157] In addition, the steering system according to the fifth aspect of the present disclosure is configured such that, based on the steering system according to any one of the first aspect to the fourth aspect, the state transition condition includes an authentication condition for authenticating a specific user who can instruct the controller to perform a state transition.

[0158] In addition, the steering system according to the sixth aspect of the present disclosure is configured such that, based on the steering system according to the fifth aspect, the authentication condition includes a manager authentication condition for authenticating a manager who manages the vehicle among the specific users.

[0159] In addition, the steering system according to the seventh aspect of the present disclosure is configured such that, based on the steering system of the fifth aspect or the sixth aspect, the authentication condition includes an authorized user authentication condition for authenticating an authorized user who is permitted by the administrator of the managed vehicle among specific users.

[0160] In addition, the steering system according to the eighth aspect of the present disclosure is configured such that, based on the steering system of any one of the first aspect to the seventh aspect, the state transition condition includes a stop condition for stopping the operation of the operating device in the sub-control state.

[0161] In addition, the steering system according to the ninth aspect of the present disclosure is configured such that, based on the steering system of the eighth aspect, the stop condition includes an abnormality determination condition for determining that an abnormality has occurred in the state of the vehicle.

[0162] In addition, the steering system according to the tenth aspect of the present disclosure is configured such that, based on the steering system of the eighth aspect or the ninth aspect, the stop condition includes a disconnection determination condition for determining that the power supply of the vehicle has been disconnected.

[0163] In addition, the steering system according to the eleventh aspect of the present disclosure is configured such that, based on the steering system of any one of the first aspect to the tenth aspect, when determining whether to permit a state transition, in addition to determining whether the state transition condition is satisfied, the state transition permission unit also determines whether the systems constituting the vehicle are normal.

[0164] In addition, the steering system according to the twelfth aspect of the present disclosure is configured such that, based on the steering system of any one of the first aspect to the eleventh aspect, the vehicle is an electric vehicle that needs to charge the battery for driving the electric motor, and the controller is configured to: when a state transition is permitted by the state transition permission unit along with the satisfaction of the state transition condition during the charging of the battery, perform a state transition from the main control state to the sub-control state.

[0165] In addition, the steering system according to the thirteenth aspect of the present disclosure is configured such that, based on the steering system of any one of the first aspect to the twelfth aspect, the controller is configured to: when performing a state transition from the sub-control state to the main control state according to the permission by the state transition permission unit, if a difference occurs between the operation position of the operation member operated in the sub-control state and the steering position of the steering wheel accompanying the above steering operation, perform alignment control to make the operation position and the steering position coincide.

[0166] In addition, the steering system according to the fourteenth aspect of the present disclosure is configured such that, based on the steering system of the thirteenth aspect, the controller is configured to: in the alignment control, operate the operating device to generate a reaction force with respect to the operation member, thereby making the operation position and the steering position coincide.

[0167] Further, the steering system according to the fifteenth aspect of the present disclosure is configured such that, based on the steering system according to any one of the first to fourteenth aspects, the controller is configured to provide entertainment of an operation member used in the vehicle in the sub-control state.

[0168] Moreover, the steering system according to the sixteenth aspect of the present disclosure is configured such that, based on the steering system according to the fifteenth aspect, the entertainment is a game that instructs the movement of a virtual moving body by operating devices mounted on the vehicle including the operation member.

Claims

1. A steering system, characterized in that the steering system includes: an operating device configured to have an operating member and generate and apply a reaction force to the operation of the operating member; a steering device configured to disconnect the mechanical connection with the operating device to steer the steering wheels of the vehicle; and a controller configured to implement the steering action of the steering wheels based on the steering device corresponding to the operation of the operating member, wherein the controller is configured to: have respective control states including a main control state for controlling the operating device and the steering device in a manner such that the operation of the operating member is synchronized with the steering action, a sub-control state for at least controlling the operating device in a manner such that the operation of the operating member is not synchronized with the steering action, and a stop state for stopping the operation of the operating device and the steering device, and perform a state transition between the main control state, the sub-control state, and the stop state; the steering system further includes a state transition permission unit configured to: when performing the state transition, determine whether a specified state transition condition associated with the safety of the vehicle is satisfied, and permit the state transition when the state transition condition is satisfied.

2. The steering system according to claim 1, characterized in that the state transition condition at least includes a vehicle-related condition associated with the state of the vehicle.

3. The steering system according to claim 2, characterized in that the vehicle-related condition includes a condition for determining at least one of the parking state of the vehicle, the communication state through a communication line built in the vehicle, the operating state of the operating device, and the operating state of the steering device.

4. The steering system according to claim 3, characterized in that when the vehicle is an electric vehicle that needs to charge a battery for driving an electric motor, the vehicle-related condition includes a condition for judging the charging state of the battery.

5. The steering system according to claim 1, characterized in that the state transition condition includes an authentication condition for authenticating a specific user who can instruct the controller to execute the state transition.

6. The steering system according to claim 5, characterized in that the authentication condition includes a manager authentication condition for authenticating a manager who manages the vehicle among the specific users.

7. The steering system according to claim 6, characterized in that the authentication condition includes a permitted user authentication condition for authenticating a permitted user among the specific users permitted by the manager.

8. The steering system according to claim 1, characterized in that the state transition condition includes a stop condition for stopping the operation of the operating device in the sub-control state.

9. The steering system according to claim 8, characterized in that the stop condition includes an abnormality determination condition for determining that an abnormality has occurred in the state of the vehicle.

10. The steering system according to claim 9, characterized in that The stop condition includes a cut-off determination condition for determining that the power supply of the vehicle has been cut off.

11. The steering system according to claim 1, wherein the state transition permission unit is configured to when determining whether to permit the state transition, in addition to determining whether the state transition condition is satisfied, also determine whether the systems constituting the vehicle are normal.

12. The steering system according to claim 1, wherein the vehicle is an electric vehicle that needs to charge a battery for driving an electric motor, the controller is configured to during charging of the battery, when the state transition is permitted by the state transition permission unit along with the satisfaction of the state transition condition, perform the state transition from the main control state to the sub-control state.

13. The steering system according to claim 1, wherein the controller is configured to when performing the state transition from the sub-control state to the main control state based on the permission by the state transition permission unit, if a difference occurs between the operation position of the operation member operated in the sub-control state and the steering position of the steering wheel accompanying the steering operation, perform alignment control to make the operation position coincide with the steering position.

14. The steering system according to claim 13, wherein the controller is configured to in the alignment control, operate the operating device to generate a reaction force with respect to the operation member, thereby making the operation position coincide with the steering position.

15. The steering system according to claim 1, wherein the controller is configured to in the sub-control state, provide entertainment using the operation member in the vehicle.

16. The steering system according to claim 15, wherein the entertainment is a game that instructs the movement of a virtual moving body by operating devices mounted on the vehicle including the operation member.

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