Vehicle control device

Abstract

To provide a technique to execute hard protection control suitable for an operation mode.SOLUTION: A vehicle control device executes: first hard protection control based on a component related parameter representing a state or an operating environment of an on-vehicle component when an operation mode is automatic; and second hard protection control offering greater protection for the on-vehicle component than the first hard protection control based on the component related parameter when the operation mode is manual.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a vehicle control device for use in a vehicle having an autonomous driving mode and a manual driving mode. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there has been proposed a technique for protecting in-vehicle components by controlling to limit output torque when the oil temperature of a vehicle transmission is high (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-214408 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the inventors of the present disclosure have found that the necessity for component protection changes depending on whether the vehicle is running in a manual driving mode or an autonomous driving mode. Therefore, it is desirable to provide component protection suitable for the driving mode. [Means for solving the problem]

[0005] (1) According to one aspect of the present disclosure, there is provided a vehicle control device for use in a vehicle having an autonomous driving mode and a manual driving mode as driving modes, the vehicle control device executes a first hardware protection control in response to a part-related parameter that indicates a state or an operating environment of an on-vehicle part when the driving mode is the autonomous driving mode, and executes a second hardware protection control that provides higher protection performance for the on-vehicle part than the first hardware protection control in response to the part-related parameter when the driving mode is the manual driving mode. According to this vehicle control device, the protection performance of on-board components can be improved in the manual driving mode compared to the automatic driving mode, and the driving performance of the vehicle can be improved in the automatic driving mode compared to the manual driving mode. (2) In the above vehicle control device, the autonomous driving mode includes a manned autonomous driving mode and an unmanned autonomous driving mode, and the vehicle control device may be configured, in the first hardware protection control, to provide higher protection performance for the on-board components in the manned autonomous driving mode than in the unmanned autonomous driving mode. According to this vehicle control device, the protection performance of on-board components can be improved in the manned autonomous driving mode compared to the unmanned autonomous driving mode, and the vehicle's driving performance can be improved in the unmanned autonomous driving mode compared to the manned autonomous driving mode. (3) The vehicle control device may be capable of executing the autonomous driving mode at a plurality of autonomous driving levels, and the vehicle control device may be configured to provide higher protection performance for the on-board components when the autonomous driving level is a first level than when the autonomous driving level is a second level higher than the first level. According to this vehicle control device, it is possible to improve the protection performance of on-board components when the autonomous driving level is low, and to improve the driving performance of the vehicle when the autonomous driving level is high. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is an explanatory diagram showing a configuration of a power transmission system of a vehicle. [Diagram 2] 4 is a timing chart showing an example of the operation of hardware protection control. [Diagram 3] FIG. 2 is an explanatory diagram showing examples of on-vehicle parts that are subject to hardware protection control, part-related parameters, and hardware protection limit values. [Figure 4] 5 is a flowchart showing a processing procedure of hardware protection control in the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] 1 is an explanatory diagram showing the configuration of a power transmission system of a vehicle 100. The vehicle 100 has an automatic driving mode and a manual driving mode as driving modes. The vehicle 100 includes an internal combustion engine 10, a motor drive unit 20, a transmission 30, a differential 40, a plurality of drive wheels 50, and a vehicle control device 80.

[0008] The transmission 30 includes a first clutch 31, an electric motor 32, a lock-up clutch 33, and an automatic transmission 34. The first clutch 31 has a function of disconnecting the engine 10 and the electric motor 32. The electric motor 32 is driven by the motor drive unit 20 as necessary to assist the driving force of the vehicle 100. In addition, with the engine 10 completely disconnected by the first clutch 31, it is also possible to perform EV (Electric Vehicle) running by the electric motor 32. The motor drive unit 20 includes a battery 21 and an inverter 22. The electric motor 32 is also capable of performing a regenerative operation. The regenerative power generated by the inverter 22 is charged to the battery 21.

[0009] The lock-up clutch 33 can maintain the connection between the engine 10 and the automatic transmission 34 in a slip state. In slip control of the lock-up clutch 33, the engagement force can be adjusted by an external force such as hydraulic pressure. The output shaft of the automatic transmission 34 is connected to a differential device 40. Note that the configuration of the transmission 30 shown in FIG. 1 is one example, and other configurations may be used.

[0010] Each of the driving wheels 50 is provided with a wheel speed sensor 70. The accelerator pedal 61 is provided with an accelerator opening sensor 71 for measuring an accelerator opening ACC. The brake pedal 62 is provided with a brake pedal sensor 72 for measuring a depression amount BRA of the brake pedal 62. The shift lever 63 is provided with a shift position sensor 73 for measuring a shift position LP. The engine 10 is provided with a water temperature sensor 74 for measuring a coolant temperature Tw, and an intake air temperature sensor 75 for measuring an intake air temperature Ta. The transmission 30 is provided with an oil temperature sensor 76 for measuring an oil temperature To of the hydraulic circuit, and a clutch temperature sensor 77 for measuring a clutch temperature Tc of the lock-up clutch 33. The battery 21 is provided with a battery temperature sensor 78 for measuring a battery temperature Tb. The electric motor 32 is provided with a motor temperature sensor 79 for measuring a motor temperature Tm. Measurement values ​​measured by the various sensors 70 to 79 are input to a vehicle control device 80.

[0011] The vehicle control device 80 includes a vehicle control unit 81, an automatic driving control unit 82, a driving mode setting unit 83, and a hardware protection control unit 84. The vehicle control device 80 can be configured using one or more ECUs (Electronic Control Units). The ECU has a processor, a RAM, and a ROM, and a computer program is stored in the ROM. The functions of each of the units 81 to 84 can be realized by the processor executing a computer program stored in a non-volatile storage medium. Note that some of the functions of each of these units 81 to 84 may be realized by a hardware circuit.

[0012] The vehicle control unit 81 executes various controls such as drive control, brake control, and steering angle control for driving the vehicle 100. The vehicle control unit 81 is used in both automatic driving and manual driving.

[0013] The automatic driving control unit 82 executes automatic driving of the vehicle 100. Specifically, the automatic driving control unit 82 transmits a driving force command value indicating the driving force of the driving unit (engine and motor), a brake command value indicating the operating state of the brake mechanism, and a steering angle command value indicating the steering angle of the wheels to the vehicle control unit 81. The vehicle control unit 81 executes control of each of the mechanisms to be controlled according to the received command values.

[0014] In this disclosure, "automated driving" means driving in which at least a part of the drive control, brake control, and steering angle control is performed automatically. That is, the term "automated driving" includes automatic driving from level 1 to level 5. Automatic driving at levels 1 and 2 requires monitoring by a driver, so it is called "manned automatic driving". Manned automatic driving includes driving using adaptive cruise control and lane keep assist system. Automatic driving at levels 3, 4, and 5 does not require monitoring by a driver, so it is called "unmanned automatic driving". In unmanned automatic driving, the operating state of the drive unit, the operating state of the brake mechanism, and the steering angle of the wheels are automatically determined. "Manual driving" means driving in which the driver operates the accelerator pedal for driving unit control, the brake pedal for brake control, and the steering wheel for steering angle control.

[0015] The driving mode setting unit 83 switches the driving mode of the vehicle 100 between a manual driving mode and an automatic driving mode. In the automatic driving mode, the level of automatic driving to be performed is also set. The driving mode can be switched, for example, by the occupant selecting an option displayed on the display. In addition, the driving mode switch may be received from an external device via wireless communication.

[0016] The hardware protection control unit 84 executes hardware protection control of the on-board components. The hardware protection control is control performed to protect the on-board components, and can also be called "component protection control." In this embodiment, in particular, the hardware protection control unit 84 executes protection control of the components of the power transmission system.

[0017] Fig. 2 is a timing chart showing an example of the operation of the hardware protection control. Fig. 2 shows an example of changes in the part-related parameter Tp and the hardware protection limit value Lim. The part-related parameter Tp is a parameter that represents the state or operating environment of the on-board part to be protected. A typical example of the part-related parameter Tp is the temperature of the on-board part. The hardware protection limit value Lim is a characteristic value that is limited for hardware protection, such as output or torque.

[0018] The part-related parameter Tp is set with a first threshold T1 for determining the start timing of the hardware protection and a second threshold T2 for determining the end timing of the hardware protection. The second threshold T2 is set to a value smaller than the first threshold T1.

[0019] The hard protection limit value Lim is set to a normal limit value Lim1 when the hard protection control is not executed, and to an enhanced protection limit value Lim2 when the hard protection control is executed. The enhanced protection limit value Lim2 is set to a value lower than the normal limit value Lim1.

[0020] Before time t1, the part-related parameter Tp is less than the first threshold T1, so the normal limit value Lim1 is applied. When the part-related parameter Tp becomes equal to or greater than the first threshold value T1 at time t1, the hardware protection control is started at time t2 after a preset delay time Δt, and the enhanced protection limit value Lim2 is applied as the hardware protection limit value. However, if the part-related parameter Tp becomes equal to or less than the second threshold value T2 during the delay time Δt, the hardware protection control is not started, and the normal limit value Lim1 is maintained.

[0021] In the period from time t2 to time t3, the part-related parameter Tp is maintained at or above the second threshold T2, so the enhanced protection limit value Lim2 is applied. After time t3, the part-related parameter Tp becomes less than the second threshold T2, so the hardware protection control ends and the normal limit value Lim1 is applied. Such hardware protection control can prevent malfunctions such as breakdowns in the on-board parts.

[0022] FIG. 3 is an explanatory diagram showing an example of on-board parts that are targets of the hardware protection control, part-related parameters Tp, and hardware protection limit values. For example, the engine 10, the clutch 33, the automatic transmission 34, the electric motor 32, and the battery 21 are applied as on-board parts that are targets of the hardware protection control. As the part-related parameter Tp of the engine 10, the intake air temperature Ta or the outside air temperature may be used, or the cooling water temperature Tw may be used. The intake air temperature Ta or the outside air temperature is a parameter indicating the operating environment of the engine 10. The cooling water temperature Tw is a parameter indicating the state of the engine 10. In the example of FIG. 3, the part-related parameters Tp of the on-board parts other than the engine 10 are parameters indicating the state of each on-board part. The hardware protection limit values ​​are the outputs of the engine 10, the electric motor 32, and the battery 21, and are torques of the clutch 33 and the automatic transmission 34. Note that the hardware protection control may be applied to only some of these on-board parts. In addition, on-board parts other than these may be targets of the hardware protection control.

[0023] 4 is a flowchart showing a procedure for hardware protection control in the embodiment. The process in FIG. 4 is preferably executed periodically at regular intervals. In the present embodiment, the following three types of hardware protection control are used. <Hardware protection priority control> Of the three types of hardware protection control, this control has the highest hardware protection performance and the lowest driving performance. <Control for achieving both hardware protection and driving performance> Of the three types of hardware protection, this control has intermediate performance in terms of both hardware protection and driving performance. <Driving performance priority control> Of the three types of hardware protection control, this control has the highest driving performance and the lowest hardware protection performance.

[0024] In step S10, the hardware protection control unit 84 determines whether the current driving mode of the vehicle 100 is the automatic driving mode or the manual driving mode. If the current driving mode is the manual driving mode, the process proceeds to step S30, where the hardware protection control unit 84 executes hardware protection priority control.

[0025] If the current driving mode is the automatic driving mode, the process proceeds to step S20, where the hardware protection control unit 84 determines whether the driving mode is the unmanned automatic driving mode or the manned automatic driving mode. As described above, the unmanned automatic driving mode is automatic driving at levels 3 to 5, and the manned automatic driving mode is automatic driving at levels 1 to 2. If the driving mode is the manned automatic driving mode, the process proceeds to step S40, where the hardware protection control unit 84 executes hardware protection / driving performance compatibility control.

[0026] If the current driving mode is the unmanned automatic driving mode, the process proceeds to step S50, where the hardware protection control unit 84 executes driving performance priority control.

[0027] As described above, in this embodiment, three types of hardware protection control can be used: hardware protection priority control, hardware protection / driving performance compatibility control, and driving performance priority control. When the driving mode is the manual driving mode, hardware protection control is executed, which provides higher protection performance for on-board components than when the driving mode is the autonomous driving mode. Note that the hardware protection / driving performance compatibility control and the driving performance priority control correspond to the "first hardware protection control" in this disclosure, and the hardware protection priority control corresponds to the "second hardware protection control" in this disclosure.

[0028] In the hardware protection control, for example, at least one of the following methods can be used to improve the hardware protection performance. <Method M1> The first threshold value T1 of the part-related parameter Tp is reduced. When using method M1, the first threshold T1 is set to the lowest value in hardware protection priority control, set to the highest value in driving performance priority control, and set to an intermediate value between them in hardware protection / driving performance compatible control. <Method M2> Shorten the delay time Δt. When using method M2, the delay time Δt is set to the longest value in hardware protection priority control, the shortest value in driving performance priority control, and an intermediate value between them in hardware protection / driving performance compatible control. <Method M3> Lower the strengthened protection limit value Lim2. When using method M3, the enhanced protection limit value Lim2 is set to the lowest value in hardware protection priority control, set to the highest value in driving performance priority control, and set to an intermediate value between them in hardware protection / driving performance compatible control. Two or more of the methods M1 to M3 may be used, or a method other than these may be used.

[0029] Thus, in this embodiment, when the driving mode is the manual driving mode, the hardware protection control is executed with higher protection performance of the on-board parts than in the automatic driving mode. The reason for this is that in the manual driving mode, since the driving environment and the driver's operation are unknown, it is necessary to execute the hardware protection control assuming the worst case scenario, and it is desirable to execute the hardware protection control with high hardware protection performance. On the other hand, in the automatic driving mode, since the vehicle 100 runs according to the driving plan, the driving environment is almost known, so there is a low possibility that a malfunction such as a failure will occur in the on-board parts, and it is desirable to improve the driving performance. In particular, in the unmanned automatic driving mode, the predictability of the driving environment is even higher, so it is desirable to further emphasize the driving performance. In particular, in the unmanned automatic driving mode in which the vehicle runs on a fixed course, there are cases where a shift control is performed to trace the driving of a professional driver, and there is a strong tendency to emphasize the driving performance. In such an unmanned automatic driving mode, the part-related parameter Tp exceeds the first threshold value T1 only for a very short time and then immediately decreases, so it is expected that there is a low possibility that a malfunction such as a failure will occur in the on-board parts.

[0030] 4 may be omitted and the same hardware protection control may be executed for the autonomous driving mode regardless of its level. In this case, it is preferable that the hardware protection control in the manual driving mode has higher protection performance for the on-board components than the hardware protection control in the autonomous driving mode.

[0031] In this embodiment, the autonomous driving modes are classified into a manned autonomous driving mode, which is an autonomous driving level 1 to 2, and an unmanned autonomous driving mode, which is an autonomous driving level 3 to 5, but the autonomous driving modes may be classified into three or more. In this case, too, it is preferable that the hardware protection control unit 84 executes hardware protection control so as to increase the protective performance of the on-board components when the autonomous driving level is the first level, compared to when the autonomous driving level is the second level, which is higher than the first level. In this way, the protective performance of the on-board components can be increased when the autonomous driving level is lower.

[0032] As described above, in this embodiment, when the driving mode is the manual driving mode, the hardware protection control is executed to provide higher protection performance for the on-board components than in the autonomous driving mode. As a result, the manual driving mode can provide higher protection performance for the on-board components than in the autonomous driving mode, and the autonomous driving mode can provide higher driving performance for the vehicle than in the manual driving mode.

[0033] In the above embodiment, a vehicle equipped with a power transmission system including an engine has been described, but the present disclosure is also applicable to electric vehicles such as battery electric vehicles.

[0034] Other forms: The present disclosure is not limited to the above-mentioned embodiment, and can be realized in various forms without departing from the spirit of the present disclosure. For example, the present disclosure can be realized in the following aspects. The technical features in the above-mentioned embodiments corresponding to the technical features in each aspect described below can be appropriately replaced or combined in order to solve some or all of the problems of the present disclosure, or to achieve some or all of the effects of the present disclosure. Furthermore, if the technical feature is not described as essential in this specification, it can be appropriately deleted.

[0035] The present disclosure may be realized in various forms other than a vehicle control device or a control method, for example, a computer program for controlling a vehicle, a non-transitory storage medium on which a computer program is recorded, or the like. [Explanation of symbols]

[0036] 10...engine, 20...motor drive unit, 21...battery, 22...inverter, 30...transmission device, 31...first clutch, 32...electric motor, 33...lock-up clutch, 34...automatic transmission, 40...differential device, 50...drive wheels, 61...accelerator pedal, 62...brake pedal, 63...shift lever, 70...wheel speed sensor, 71...accelerator opening sensor, 72...brake pedal sensor, 73...shift position sensor, 74...water temperature sensor, 75...oil temperature sensor, 76...clutch temperature sensor, 77...battery temperature sensor, 78...motor temperature sensor, 79...intake air temperature sensor, 80...vehicle control device, 81...vehicle control unit, 82...automatic driving control unit, 83...driving mode setting unit, 84...hardware protection control unit, 100...vehicle

Claims

1. A vehicle control device used in a vehicle having an automatic driving mode and a manual driving mode as driving modes, When the driving mode is the autonomous driving mode, a first hardware protection control is executed in response to a part-related parameter indicating a state or an operating environment of an in-vehicle part; When the driving mode is the manual driving mode, the vehicle control device executes a second hardware protection control that provides higher protection performance for the on-vehicle components than the first hardware protection control, depending on the component-related parameters.

2. The vehicle control device according to claim 1, The autonomous driving mode includes a manned autonomous driving mode and an unmanned autonomous driving mode, The vehicle control device is configured, in the first hardware protection control, to provide higher protection performance for the on-board components in the manned autonomous driving mode than in the unmanned autonomous driving mode.

3. The vehicle control device according to claim 1, The vehicle control device is capable of executing the autonomous driving mode at a plurality of autonomous driving levels, The vehicle control device is configured to provide higher protection performance for the on-board components when the autonomous driving level is a first level than when the autonomous driving level is a second level higher than the first level.

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