Patent ID: 12240339

DETAILED DESCRIPTION OF EMBODIMENTS

An embodiment will be described below with reference to the drawings.

Prerequisite Configuration

FIG.1shows the configuration of a steering control system of a vehicle according to the embodiment. This embodiment assumes, as a steering system, a so-called steer-by-wire system in which a power transmission path between a steering wheel and turning wheels is cut off.

A battery10is a supply source of electricity to electronic equipment of the vehicle. The battery10can supply electricity through a main power source line Lb as well as can supply electricity through a start switch12and a start line Lig. The start switch12is a switch that allows the vehicle to travel. The start switch12is switched from one to the other of an on state and an off state by operation of a user of the vehicle. When the vehicle includes an internal combustion engine, the start switch12may be an ignition switch. When the vehicle includes a motor-generator, the start switch12may be a switch that operates in conjunction with turning on and off of a system main relay between an inverter connected to the motor-generator and a high-voltage battery.

A steering main control device100is a device that controls the state of the steering wheel by operating a reaction force actuator. The reaction force actuator is an actuator that applies a reaction force that is a force resisting operation of the steering wheel. The reaction force actuator includes a reaction force motor, and a reaction force is generated by a torque of the reaction force motor.

The steering main control device100includes an inverter110and a steering main microcomputer120. The inverter110applies an alternating-current voltage to terminals of a motor included in the reaction force actuator. The steering main microcomputer120operates the inverter110so as to control the steering wheel as a control target.

A steering sub control device200is a device that controls the state of the steering wheel by operating the reaction force actuator. The reaction force actuator is an actuator that applies a reaction force that is a force resisting operation of the steering wheel.

The steering sub control device200includes an inverter210and a steering sub microcomputer220. The inverter210applies an alternating-current voltage to terminals of a motor included in the reaction force actuator. A configuration may be adopted in which the inverter110and the inverter210apply an alternating-current voltage to different stator coils of the reaction force motor that share a rotor. The steering sub microcomputer220operates the inverter210so as to control the steering wheel as a control target. A voltage in the start line Lig is applied to the steering sub microcomputer220through a diode18. The diode18has an anode side on the side of the battery10and a cathode side on the side of the steering sub microcomputer220. A terminal voltage of the battery10is applied to the steering sub microcomputer220through a diode16, without the start switch12being interposed. The diode16has an anode side on the side of the battery10and a cathode side on the side of the steering sub microcomputer220.

A turning main control device300is a device that controls the state of turning wheels by operating a turning actuator. The turning actuator is an actuator that turns the turning wheels. The turning actuator includes a turning motor and turns the turning wheels by a torque of the turning motor.

The turning main control device300includes an inverter310and a turning main microcomputer320. The inverter310applies an alternating-current voltage to terminals of a motor included in the turning actuator. The turning main microcomputer320operates the inverter310so as to control the turning wheels as a control target.

A turning sub control device400is a device that controls the state of the turning wheels by operating the turning actuator. The turning sub control device400includes an inverter410and a turning sub microcomputer420. The inverter410applies an alternating-current voltage to terminals of a motor included in the turning actuator. A configuration may be adopted in which the inverter310and the inverter410apply an alternating-current voltage to different stator coils of the turning motor that share a rotor. The turning sub microcomputer420operates the inverter410so as to control the turning wheels as a control target. A voltage in the start line Lig is applied to the turning sub microcomputer420through a diode22. The diode22has an anode side on the side of the battery10and a cathode side on the side of the turning sub microcomputer420. A terminal voltage of the battery10is applied to the turning sub microcomputer420through a diode20, without the start switch12being interposed. The diode20has an anode side on the side of the battery10and a cathode side on the side of the turning sub microcomputer420.

An auxiliary control device500is a device that controls the state of an auxiliary power source530as a control target. The auxiliary power source530is an electricity storage device that stores electric charge from the battery10. The auxiliary power source530may be, for example, a capacitor. The auxiliary control device500may use the main power source as a power source.

The auxiliary control device500includes a switching element510that opens and closes a path between the main power source line Lb and the inverters110,310. The auxiliary control device500includes a switching element512that opens and closes a path between the main power source line Lb and the auxiliary power source530through the switching element510. The auxiliary control device500includes a diode516that connects the auxiliary power source530on one side and the steering main microcomputer120and the turning main microcomputer320on the other side to each other. The diode516is a rectifier element that has an anode on the side of a positive electrode terminal of the auxiliary power source530and a cathode on the side of the steering main microcomputer120and the turning main microcomputer320. The auxiliary control device500includes a diode518that connects the start line Lig on one side and the steering main microcomputer120and the turning main microcomputer320on the other side to each other. The diode518is a rectifier element that has an anode on the side of the battery10and a cathode on the side of the steering main microcomputer120and the turning main microcomputer320. Specifically, the steering main microcomputer120is connected to the cathode sides of the diodes516,518through a diode517. The diode517is a rectifier element that has an anode side on the cathode sides of the diodes516,518and a cathode side on the side of the steering main microcomputer120. The turning main microcomputer320is connected to the cathode sides of the diodes516,518through a diode519. The diode519is a rectifier element that has an anode side on the cathode sides of the diodes516,518and a cathode side on the side of the turning main microcomputer320. The auxiliary control device500includes a switching element514that opens and closes a path between the anode side of the diode516and the auxiliary power source530.

The auxiliary control device500includes an auxiliary microcomputer520. The auxiliary microcomputer520detects a voltage and a current of the auxiliary power source530and monitors the state of the auxiliary power source530. The auxiliary microcomputer520controls supply of electricity from the battery10to the inverters110,310by opening and closing the switching element510. The auxiliary microcomputer520controls exchange of electricity between the auxiliary power source530and the battery10and exchange of electricity between the inverters110,310and the auxiliary power source530by opening and closing the switching element512. The auxiliary microcomputer520controls supply of electricity from the auxiliary power source530to the steering main microcomputer120and the turning main microcomputer320by opening and closing the switching element514. The auxiliary microcomputer520maintains the switching element514in a closed state during a period when the auxiliary microcomputer520is running.

The steering main microcomputer120and the steering sub microcomputer220can communicate with each other through a local line30. The turning main microcomputer320and the turning sub microcomputer420can communicate with each other through a local line32. The steering main microcomputer120and the turning main microcomputer320can communicate with each other through an inter-main communication line40. The steering main microcomputer120and the steering sub microcomputer220are connected to a gateway70through a bus line50. The turning main microcomputer320and the turning sub microcomputer420are connected to the gateway70through a bus line60. The auxiliary microcomputer520and the steering main microcomputer120can communicate with each other through a local line80.

FIG.2shows the configurations of the steering main microcomputer120, the steering sub microcomputer220, the turning main microcomputer320, the turning sub microcomputer420, and the auxiliary microcomputer520. InFIG.2, variable i is “1 to 5” (i=1 to 5). That is, when the variable i is “1,” “i20” indicates “120.”

As shown in the drawing, the aforementioned five microcomputers include PUs122,222,322,422,522, respectively. The aforementioned five microcomputers include ROMs124,224,324,424,524, respectively. The aforementioned five microcomputers include RAMs126,226,326,426,526, respectively. The PUs122,222,322,422,522are software processing devices including at least one processing unit, such as a CPU, GPU, or TPU. The ROMs124,224,324,424,524store programs that the PUs122,222,322,422,522execute.

Control of Sub Systems

FIG.3shows the procedure of processing executed by the PU222of the steering sub microcomputer220and the PU422of the turning sub microcomputer420. The processing shown inFIG.3is processing that is realized as the PU222executes a program stored in the ROM224repeatedly, for example, on a predetermined cycle. Further, the processing shown inFIG.3is processing that is realized as the PU422executes a program stored in the ROM424repeatedly, for example, on a predetermined cycle. In the following, the step number of each process will be represented by a number given an “S” at the beginning. For the convenience of description, the processing executed by the PU222will be described as an example below. The processing executed by the PU422is one for which a voltage Vss is read as a voltage Vst in the following description.

In the series of processes shown inFIG.3, the PU222first detects the voltage Vss (S10). The voltage Vss is a voltage in the start line Lig connected to the steering sub control device200. That is, the voltage Vss is a voltage on the anode side of the diode18. On the other hand, the voltage Vst is a voltage in the start line Lig connected to the turning sub control device400. That is, the voltage Vst is a voltage on the anode side of the diode22. Next, the PU222determines whether the logical product of the following Condition (SS1) and Condition (SS2) is true (S12).

Condition (SS1): a condition that a command signal for turning the start switch off has been received. InFIG.3, this is indicated as “IGOFF COMMAND HAS BEEN RECEIVED.” This command signal is input into the steering sub microcomputer220through the bus line50. The command signal may be a signal that is generated by, for example, another control device that is not shown inFIG.1.

Condition (SS2): a condition that the voltage Vss is equal to or lower than a threshold value Vth. Here, the threshold value Vth may be set to be smaller than a maximum value of a voltage that the start line Lig can assume when the start switch12is in an open state.

When the PU222determines that the above-described logical product is true (S12: YES), the PU222makes an IG off determination that is a determination that the start switch is off (S14). Then, the PU222transmits a sub-side off determination that is a determination result that the start switch is off to the steering main microcomputer120through the local line30(S16). Then, the PU222determines whether it is confirmed that the start switch is in the off state (IG off) (S18). Here, the PU222determines that IG off is confirmed on the condition, for example, that information that the steering main microcomputer120has determined that the start switch is off is transmitted from the steering main microcomputer120through the local line30. When the PU222determines that the IG off is confirmed (S18: YES), the PU222executes a process of stopping the steering sub microcomputer220(S20).

In the case where the PU222executes the process of S20and the case where the PU222determines in the negative in the processes of S12and S18, the PU222temporarily ends the series of processes shown inFIG.3.

Control of Steering Main Microcomputer

FIG.4shows the procedure of processing executed by the PU122of the steering main microcomputer120. The processing shown inFIG.4is processing that is realized as the PU122executes a program stored in the ROM124repeatedly, for example, on a predetermined cycle.

In the series of processes shown inFIG.4, the PU122first detects a voltage Vms on the cathode sides of the diodes516,518(S30). The voltage Vms is a voltage on the anode side of the diode517. Next, the PU122determines whether the logical product of the following Condition (MS1) and Condition (MS2) is true (S32).

Condition (MS1): a condition that a command signal for turning the start switch off has been received. InFIG.4, this is indicated as “IGOFF COMMAND HAS BEEN RECEIVED.” This command signal is input into the steering main microcomputer120through the bus line50. The command signal may be a signal that is generated by, for example, another control device that is not shown inFIG.1.

Condition (MS2): a condition that the voltage Vms is equal to or lower than a threshold value Vth. When the PU122determines that the above-described logical product is true (S32: YES), the PU122makes an IG off determination that is a determination that the start switch is off (S34). Then, the PU122determines whether the determination that the start switch is in the off state (IG off determination) is confirmed (S36). The PU122confirms the determination that the start switch is in the off state on the condition, for example, that it is determined that a sub-side off determination has been transmitted. Then, the PU122executes a process of stopping the steering main microcomputer120(S38).

In the case where the PU222executes the stop process of S38and the case where the PU222determines in the negative in the processes of S32and S36, the PU222temporarily ends the series of processes shown inFIG.4.

Processing in Auxiliary Microcomputer520, Steering Main Microcomputer120, and Turning Main Microcomputer320

FIG.5shows the procedures of processing executed by the auxiliary microcomputer520, the steering main microcomputer120, and the turning main microcomputer320. One of the three series of processes shown inFIG.5is realized as the PU522executes a program stored in the ROM524repeatedly, for example, on a predetermined cycle. Another one of the three series of processes shown inFIG.5is realized as the PU122executes a program stored in the ROM124repeatedly, for example, on a predetermined cycle. The remaining one of the three series of processes shown inFIG.5is realized as the PU322executes a program stored in the ROM324repeatedly, for example, on a predetermined cycle. In the following, the series of processes shown inFIG.5will be described in chronological order in which these processes can actually occur.

In the series of processes shown inFIG.5, the PU522first detects a voltage Vpgs in the start line Lig connected to the auxiliary control device500(S50). The voltage Vpgs is a voltage on the anode side of the diode518. Next, the PU522transmits the voltage Vpgs to the steering main microcomputer120through the local line80(S52).

Meanwhile, the PU122of the steering main microcomputer120receives the voltage Vpgs (S60). Then, the PU122determines whether the voltage Vpgs is equal to or lower than the threshold value Vth (S62). This process is a process of determining whether the start switch12is in the off state. When the PU122determines that the voltage Vpgs is equal to or lower than the threshold value Vth (S62: YES), the PU122substitutes “1” to a determination flag Fpgs (S64). On the other hand, when the PU122determines that the voltage Vpgs is higher than the threshold value Vth (S62: NO), the PU122substitutes “0” to the determination flag Fpgs (S66). In the case where the PU122completes the process of S64or S66, the PU122transmits the value of the determination flag Fpgs to the turning main microcomputer320through the inter-main communication line40(S68).

Meanwhile, the PU322of the turning main microcomputer320determines whether the value of the determination flag Fpgs has been received (S80). When the PU322determines that the value has been received (S80: YES), the PU322detects a voltage Vmt on the cathode sides of the diodes516,518(S82). The voltage Vmt is a voltage on the anode side of the diode519. Next, the PU422determines whether the logical product of the following Condition (MT1), and a condition that the logical sum of the following Condition (MT2) and Condition (MT3) is true, is true (S84).

Condition (MT1): a condition that a command signal for turning the start switch off has been received. InFIG.5, this is indicated as “IGOFF COMMAND HAS BEEN RECEIVED.” This command signal is input into the turning main microcomputer320through the bus line60. The command signal may be a signal that is generated by, for example, another control device that is not shown inFIG.1.

Condition (MT2): a condition that the voltage Vmt is equal to or lower than the threshold value Vth. Condition (MT3): a condition that the determination flag Fpgs is “1.” When the PU322determines that the logical product is true (S84: YES), the PU322determines that the start switch is off (IG off determination) and stores that information in the RAM326(S86). On the other hand, when the PU322determines in the negative in the process of S84, the PU322determines that the start switch is in the on state and stores that information in the RAM326(S88).

In the case where the PU322completes the process of S86or S88and the case where the PU322determines in the negative in the process of S80, the PU322determines whether the determination result of the start switch being off is stored in the RAM326(S90). When the PU322determines that the off determination result is stored (S90: YES), the PU322transmits information that an IG off determination (turning-side off determination) has been made on the side of the turning main microcomputer320through the inter-main communication line40(S92).

Meanwhile, the PU122of the steering main microcomputer120determines whether the determination result that the start switch is off transmitted from the turning main microcomputer320has been received (S70). When the PU122determines that the determination result has been received (S70: YES), the PU122transmits a permission signal that permits the auxiliary microcomputer520to be turned off through the local line80(S72). In the case where the PU122completes the process of S72and the case where the PU122determines in the negative in the process of S70, the PU122temporarily ends the series of processes shown inFIG.5.

Meanwhile, the PU522of the auxiliary microcomputer520determines whether the logical product of the following Condition (AS1) and Condition (AS2) is true (S54). Condition (AS1): a condition that the permission signal has been received.

Condition (AS2): a condition that the voltage Vpgs is equal to or lower than the threshold value Vth. When the PU522determines that the above-described logical product is true (S54: YES), the PU522executes a process of stopping the auxiliary microcomputer520(S56). The process of stopping the auxiliary microcomputer520includes a process in which the auxiliary microcomputer520opens the switching element514. In the case where the PU522completes the process of S56and the case where the PU522determines in the negative in the process of S54, the PU522temporarily ends the series of processes shown inFIG.5.

On the other hand, in the case where the PU322of the turning main microcomputer320completes the process of S92, the PU322determines whether the off state of the start switch is confirmed (S94). Here, the PU322confirms the determination that the start switch is off when a condition is met such as that the determination result that the start switch is in the off state has been received from the turning sub microcomputer420by the process of S16inFIG.3. When the determination that the start switch is off is confirmed (S94: YES), the PU322puts the turning main microcomputer320into an off state (S96).

In the case where the PU322completes the process of S96and the case where the PU322determines in the negative in the process of S90or S94, the PU322temporarily ends the series of processes shown inFIG.5.

Setting of Initial Value

FIG.6shows the procedure of processing relating to setting of an initial value in a part of a storage area of the RAM326where a determination result of the state of the start switch is stored. The processing shown inFIG.6is realized as the PU322executes a program stored in the ROM324repeatedly, for example, on a predetermined cycle.

In the series of processes shown inFIG.6, the PU322first determines whether the turning main microcomputer320is starting (S100). When the PU322determines that the turning main microcomputer320is starting (S100: YES), the PU322sets the value in the part of the storage area of the RAM326where the determination result of the state of the start switch is stored to a determination result that the start switch is on (S102). In the case where the PU322completes the process of S102and the case where the PU322determines in the negative in the process of S100, the PU322temporarily ends the series of processes shown inFIG.6.

Here, effects and advantages of the embodiment will be described. When the PU522of the auxiliary microcomputer520detects the voltage Vpgs, the PU522transmits the voltage Vpgs to the steering main microcomputer120through the local line80. The PU122of the steering main microcomputer120substitutes a comparison result of the voltage Vpgs and the threshold value Vth to the value of the determination flag Fpgs. Then, the PU122transmits the value of the determination flag Fpgs to the turning main microcomputer320through the inter-main communication line40. The PU322of the turning main microcomputer320determines that the start switch is in the off state when the logical sum of the condition that the value of the determination flag Fpgs is “1” and the condition that the voltage Vmt is equal to or lower than the threshold value Vth is true and moreover the IG off command has been received. Then, the PU322stores the determination result in the RAM326. When the determination result stored in the RAM326is a determination result that the start switch is in the off state, the PU322transmits that information to the steering main microcomputer120through the inter-main communication line40. When the steering main microcomputer120receives the determination result that the start switch is in the off state from the turning main microcomputer320, the steering main microcomputer120transmits a permission signal to the auxiliary microcomputer520. The PU522of the auxiliary microcomputer520puts the auxiliary microcomputer520into the off state on the condition that the permission signal is received.

In this way, by using the voltage Vpgs detected in the auxiliary control device500, the PU122of the steering main microcomputer120can determine the state of the start switch based on the voltage Vpgs in the start line Lig. That is, the voltage on the cathode sides of the diodes516,518is applied to the steering main microcomputer120and the turning main microcomputer320. Therefore, in the case where the start switch12is in the off state, when the voltage in the start line Lig decreases, a terminal voltage of the auxiliary power source530is applied to the steering main microcomputer120and the turning main microcomputer320. Thus, the steering main microcomputer120and the turning main microcomputer320cannot directly detect the voltage in the start line Lig.

At start-up when the start switch12switches from the open state to the closed state, the steering main microcomputer120, the turning main microcomputer320, and the auxiliary microcomputer520can vary from one another in start-up timing. For this reason, it sometimes takes time until communication between the steering main microcomputer120and the auxiliary microcomputer520is established and communication between the steering main microcomputer120and the turning main microcomputer320is established. On the other hand, microcomputers generally initialize stored data at start-up. When the value indicating the state of the start switch stored in the RAM326is set to a value indicating an off state as a result of initialization, due to a delay in establishing communication etc., a determination result of an off state is transmitted from the PU322to the steering main microcomputer120. As a result, a permission signal is transmitted from the PU122to the auxiliary microcomputer520, so that the PU522stops the auxiliary microcomputer520. That is, there is a concern that the auxiliary microcomputer520may stop accidentally at normal start-up when the start switch12is switched from the open state to the closed state. In this case, when supply of electricity from the battery10is interrupted thereafter due to breakage of the start line Lig etc., electricity of the auxiliary power source530that should be originally used becomes unavailable. This state may continue until the start switch12is closed again after it is temporarily opened.

As a countermeasure, in this embodiment, at start-up of the turning main microcomputer320, the PU322switches the determination result of the state of the start switch to a determination result that the start switch is in the on state in the process of initializing the RAM326. This helps prevent a permission signal from being accidentally transmitted to the auxiliary microcomputer520due to the aforementioned delay in communication etc.

The embodiment having been described above can further produce the following effects and advantages. (1) A communication line in which the gateway70is interposed is not provided in the communication line between the auxiliary control device500and the outside. Thus, the number of components of the steering control system can be reduced, and the cost can be reduced. In this case, however, the auxiliary microcomputer520cannot receive an off command for the start switch from the outside. In the case where the PU522of the auxiliary microcomputer520itself determines the state of the start switch from the voltage Vpgs alone, the reliability of the determination result is lower compared with when reception of the off command is taken into account. Therefore, it is particularly advantageous to generate a permission signal by determining the state of the start switch outside the auxiliary control device500.

Correspondence Relationships

The correspondence relationships between items in the above-described embodiment and items described in the section “SUMMARY” are as follows. In the following, the correspondence relationships are shown according to the numbers of the solutions described in the section “SUMMARY” [1] The driving control device corresponds to the steering main control device100and the turning main control device300. The auxiliary control device corresponds to the auxiliary control device500. The main power source corresponds to the battery10. The auxiliary power source corresponds to the auxiliary power source530. The supply path corresponds to the start line Lig. The storage process corresponds to the processes of S86and S88. The permission signal transmission process corresponds to the process of S72. The initial value process corresponds to the process of S102. The storage device corresponds to the RAM326. The permission signal reception process corresponds to the process of S54. The stop process corresponds to the process of S56. [2] This solution corresponds to being able to execute the process of S86or S88after the value of the determination flag Fpgs is received in the process of S80. [3] The voltage transmission process corresponds to the process of S52. The voltage reception process corresponds to the process of S60. The off determination process corresponds to the processes of S62to S66and S84. [4] The voltage detection process corresponds to the process of S82. [5] This solution corresponds to the output voltages of the diodes516,518being applied to the steering main microcomputer120and the turning main microcomputer320. [6] This solution corresponds to the auxiliary control device500being connected to only the steering main control device100through the local line80inFIG.1. [7] The driving circuit of the reaction force actuator corresponds to the inverter110. The driving circuit of the turning actuator corresponds to the inverter310. The steering-side determination process corresponds to the processes of S62to S66. The turning-side determination process corresponds to the process of S84. The steering-side determination result transmission process corresponds to the process of S68. The steering-side determination result reception process corresponds to the process of S80. The turning-side determination result transmission process corresponds to the process of S92. The turning-side determination result reception process corresponds to the process of S70.

Other Embodiments

The embodiment can be implemented with the following changes made thereto. The embodiment and the following modified examples can be implemented in combination to such an extent that no technical inconsistency arises.

Turning-Side Determination Process

The turning-side determination process is not limited to the process of S84. For example, Condition (MT1) may be omitted. In other words, this process may be a process of determining whether the logical sum of Condition (MT2) and Condition (MT3) is true. Further, for example, this process may be a process of determining whether the logical product of Condition (MT1) and Condition (MT3) is true.
Steering-Side Determination ProcessThe steering-side determination process is not limited to the processes of S62to S66. For example, this process may be a process of moving to S64when the logical sum of the condition that the voltage Vpgs is equal to or lower than the threshold value Vth and the condition that the voltage Vms is equal to or lower than the threshold value Vth is true.
Process of Stopping Auxiliary Control DeviceThe condition for executing the stop process is not limited to the condition that the logical product of Condition (AS1) and Condition (AS2) is true. For example, only Condition (AS1) may be used.
Communication PathFor example, the inter-main communication line40between the steering main control device100and the turning main control device300may be a path in which the gateway70is interposed.It is not essential that the configuration is such that the target with which the auxiliary control device500communicates directly is only the steering main control device100.
Control Devices that Operate Reaction Force ActuatorThe control devices that operate the reaction force actuator are not limited to the steering main control device100and the steering sub control device200. For example, only the steering main control device100may control the reaction force actuator. Further, for example, cases where a plurality of control devices that operates the reaction force actuator is provided to create redundancy are not limited to a case where two control devices are provided. For example, three or more control devices that operate the reaction force actuator may be provided.
Control Devices that Operate Turning ActuatorThe control devices that operate the turning actuator are not limited to the turning main control device300and the turning sub control device400. For example, only the turning main control device300may control the turning actuator. Further, for example, cases where a plurality of control devices that operates the turning actuator is provided to create redundancy are not limited to a case where two control devices are provided. For example, three or more control devices that operate the turning actuator may be provided.
Driving Control DevicesIt is not essential that the driving control devices include the steering main control device100and the turning main control device300. For example, these control devices may be provided as one control device. In this case, a PU, a ROM, and a storage device can be shared. Further, for example, as described later in the section “Equipment Installed in Vehicle”, in the case of a configuration in which the steering wheel is mechanically coupled to the turning wheels, the driving control device may be a device that operates an electric motor for assisting turning of the turning wheels.The driving control device is not limited to the one that includes a PU and a ROM and executes software processing. For example, the driving control device may include a dedicated hardware circuit (e.g., an ASIC) that performs hardware processing of at least some of the processes that are processed by software in the above-described embodiment. Specifically, the driving control device may be one of the following configurations (a) to (c). (a) A configuration including a processing device that executes all of the above-described processes in accordance with a program, and a program storage device, such as a ROM, that stores the program. (b) A configuration including a processing device that executes some of the above-described processes in accordance with a program, a program storage device, and a dedicated hardware circuit that executes the other processes. (c) A configuration including a dedicated hardware circuit that executes all of the above-described processes. Here, a plurality of software processing circuits including processing devices and program storage devices or a plurality of dedicated hardware circuits may be provided. Thus, the above-described processes may be executed by a processing circuit that includes at least either one or more software processing circuits or one or more dedicated hardware circuits.
Auxiliary Control DeviceThe auxiliary control device500is not limited to the one that includes the PU522and the ROM524and executes software processing. For example, the auxiliary control device may include a dedicated hardware circuit (e.g., an ASIC) that performs hardware processing of at least some of the processes that are processed by software in the above-described embodiment. Specifically, the auxiliary control device may have one of the following configurations (a) to (c). (a) A configuration including a processing device that executes all of the above-described processes in accordance with a program, and a program storage device, such as a ROM, that stores the program. (b) A configuration including a processing device that executes some of the above-described processes in accordance with a program, a program storage device, and a dedicated hardware circuit that executes the other processes. (c) A configuration including a dedicated hardware circuit that executes all of the above-described processes. Here, a plurality of software processing circuits including processing devices and program storage devices or a plurality of dedicated hardware circuits may be provided. Thus, the above-described processes may be executed by a processing circuit that includes at least either one or more software processing circuits or one or more dedicated hardware circuits.
Equipment Installed in VehicleThe equipment of which the state is controlled by the driving control device is not limited to the steering wheel and the turning wheels. For example, in the case of the configuration in which the steering wheel is mechanically coupled to the turning wheels, that equipment may be only the turning wheels.It is not essential that the equipment of which the state is controlled by the driving control device is equipment in the steering system of the vehicle.