Vehicle control device

Abstract

To provide a vehicle control device preventing a vehicle from unintentionally travelling in a free steering state where a steering angle and a turning angle are not synchronized.SOLUTION: A vehicle control device is installed on a vehicle and includes: a first determination part determining whether or not a steering angle of a steering and a turning angle of a steering wheel are in a synchronous state; a second determination part determining whether or not the vehicle is in a travelable state; and a control part controlling power supply to a first device related to vehicle travelling. The control part stops power supply to the first device when the steering angle and the travelling angle are in a synchronous state and the vehicle is in a travelable state.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a vehicle control device mounted on a vehicle. [Background technology]

[0002] Patent Document 1 discloses an automobile equipped with a redundant control device for the purpose of improving reliability or reducing the failure rate. Patent Document 1 describes a technology that uses redundancy to prevent the entire control from malfunctioning when a failure occurs in the steering control by the steer-by-wire system. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-358997 Summary of the Invention [Problem to be solved by the invention]

[0004] In a steer-by-wire system that electrically controls the steering wheels (tires) based on the operation of the steering wheel, a synchronization process is performed to control and match the steering angle of the steering wheels when the vehicle's system power is turned on (such as when the start / stop button is pressed) or when a specific electronic control unit is reset, in order to eliminate any discrepancy between the steering angle of the steering wheel and the turning angle of the steering wheels. During the period when this synchronization process is being performed, the steering operation is not transmitted to the steering wheels (hereinafter referred to as the "free steering state"), so necessary control is performed to prevent the vehicle from becoming drivable.

[0005] However, even if the steer-by-wire system is normal, if an abnormality occurs in the vehicle's driving control system due to, for example, a stuck fault in the start request signal, the vehicle may be able to drive in a free-steering state, causing the vehicle to move unintentionally. For this reason, there is room for further study of vehicle control methods in a free-steering state.

[0006] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a vehicle control device that can prevent the vehicle from unintentionally running in a free steering state in which the steering angle of the steering wheel and the turning angle of the steered wheels are not synchronized. [Means for solving the problem]

[0007] In order to solve the above problem, one aspect of the disclosed technology is a vehicle control device mounted on a vehicle, comprising: a first judgment unit that judges whether the steering angle of the steering wheel and the turning angle of the steered wheels are synchronized; a second judgment unit that judges whether the vehicle is in a state where it can run; and a control unit that controls the supply of power to a first device related to the running of the vehicle, wherein the control unit stops the supply of power to the first device when the steering angle and the turning angle are not synchronized and the vehicle is in a state where it can run. [Effects of the Invention]

[0008] According to the vehicle control device of the present disclosure, when the vehicle is in a free-steering state in which the steering angle of the steering wheel and the steered angle of the steered wheels are not synchronized and the vehicle becomes capable of traveling, the power supply to devices related to the traveling of the vehicle is stopped, thereby making it possible to prevent the vehicle from traveling unintentionally in the free-steering state. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a functional block diagram of a vehicle control device and its peripheral components according to an embodiment of the present disclosure; [Figure 2] Flowchart of power supply control process executed by the vehicle control device [Figure 3] Sequence example when the vehicle is in a free-steering state and unable to move [Figure 4] Sequence example when the vehicle is ready to drive in free steering mode DETAILED DESCRIPTION OF THE INVENTION

[0010] When the vehicle is in a state where the steering angle and the steered angle of the steered wheels are not synchronized (free steer state) and the vehicle is ready to run (READY-ON state), the vehicle control device of the present disclosure forcibly stops the operation of the electronic control unit that controls the running of the vehicle by turning off the power supply to the electronic control unit, thereby preventing the vehicle from running unintentionally in the free steer state. Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0011] <Embodiment> [composition] 1 is a functional block diagram of a vehicle control device 50 and its peripheral units according to an embodiment of the present disclosure. The functional block illustrated in FIG. 1 includes a cruise control device 10, a steering control device 20, a steered wheel control device 30, an ignition relay 40, and the vehicle control device 50.

[0012] The cruise control device 10, the steering control device 20, the steering wheel control device 30, the ignition relay 40, and the vehicle control device 50 can be mounted on an electrically powered vehicle such as an electric vehicle (BEV).

[0013] The cruise control device 10 (first device) is an electronic control unit (ECU) that controls the vehicle system, and is particularly capable of performing control related to vehicle driving. The cruise control device 10 is configured to operate using power supplied from a power supply unit 100 that is connected when an ignition relay 40 is in a conductive state. Until receiving a start request signal from the vehicle control device 50, the cruise control device 10 transmits a multiplex communication signal to the vehicle control device 50 indicating that the vehicle is in a state where it cannot drive (READY-OFF). When the cruise control device 10 receives the start request signal from the vehicle control device 50 and completes predetermined processing required for driving, the cruise control device 10 transmits a multiplex communication signal to the vehicle control device 50 indicating that the vehicle is in a state where it can drive (READY-ON). The signal (multiplex communication signal) indicating READY-OFF or READY-ON is transmitted and received via an in-vehicle network such as a CAN (Controller Area Network). An example of the cruise control device 10 is a BEV-ECU.

[0014] The steering control device 20 (second device) is an electronic control unit (ECU) that controls the steering of the wheels to change the direction of travel of the vehicle based on the steering angle corresponding to the rotation of the steering wheel (not shown) by the vehicle driver. When a synchronization process is performed to control the steering angle to match the turning angle of the steered wheels (not shown), the steering control device 20 periodically transmits a synchronization process status signal (multiplex communication signal) indicating the status of the synchronization process on the steering side to the vehicle control device 50. The synchronization process status signals include a "synchronization completion signal" indicating that the synchronization process has been completed, a "synchronization incomplete signal" indicating that the synchronization process has not been completed, and an "unconfirmed signal" indicating that the synchronization has not been determined, for example, during initialization process immediately after power-on. The synchronization process status signal is transmitted and received via an in-vehicle network such as a CAN.

[0015] The steering wheel control device 30 (third device) is an electronic control unit (ECU) that controls the steering angle of the steering wheels in accordance with the steering angle of the steering wheel. When synchronization processing is performed to control the steering angle of the steering wheel and the steering angle of the steering wheels to coincide with each other, the steering wheel control device 30 periodically transmits a synchronization processing status signal (multiplex communication signal) indicating the status of the synchronization processing on the steering wheel side to the vehicle control device 50. As described above, the synchronization processing status signal can be a synchronization completion signal, a synchronization incompletion signal, or an undetermined signal. This synchronization processing status signal is transmitted and received via an in-vehicle network such as a CAN.

[0016] The ignition relay 40 is, for example, a single-pole, single-throw, excitation-type mechanical relay, and is provided between the power supply unit 100 and (the power supply line of) the driving control device 10. The coil unit of the ignition relay 40 is connected to the vehicle control device 50 via a dedicated line, and is driven and controlled by the vehicle control device 50.

[0017] The vehicle control device 50 is an electronic control unit (ECU) that controls the vehicle system, and is particularly capable of controlling the vehicle's power supply. When a synchronization process is performed to control and match the steering angle of the steering wheel and the turning angle of the steered wheels, the vehicle control device 50 confirms that it has received a synchronization completion signal as a synchronization process status signal from both the steering control device 20 and the steering wheel control device 30, and then transmits a start request signal to the cruise control device 10. A dedicated line is used to transmit this start request signal. The vehicle control device 50 can also receive a READY state (READY-OFF or READY-ON) from the cruise control device 10, and controls the operation of the ignition relay 40 in accordance with the READY state and the synchronization process status signal (synchronization completion signal or synchronization incomplete signal). An example of the vehicle control device 50 is a verification ECU. The operation control of the ignition relay 40 performed by the vehicle control device 50 will be described later.

[0018] Each of the above-mentioned electronic control units (ECUs) typically includes a processor, memory, an input / output interface, etc., and the functions performed by the driving control unit 10, steering control unit 20, steering wheel control unit 30, vehicle control unit 50, etc. are realized by the processor reading and executing programs stored in the memory.

[0019] [control] Next, with further reference to FIGS. 2, 3, and 4, the control performed by the vehicle control device 50 according to an embodiment of the present disclosure will be described.

[0020] Fig. 2 is a flowchart illustrating the processing procedure of power supply control (IG off control when synchronization is not completed) executed by the vehicle control device 50. The power supply control illustrated in Fig. 2 is started at a timing when synchronization processing is required to control the steering angle and the turning angle of the steered wheels to match (for example, when the power to the vehicle system is turned on or when a specific electronic control device is reset).

[0021] (Step S201) The vehicle control device 50 determines the READY state received from the driving control device 10. That is, the vehicle control device 50 determines whether the READY state is "READY-OFF" or "READY-ON." This determination is made to determine whether the vehicle is in a state where it can be driven. This determination is made periodically, for example, at predetermined intervals.

[0022] If the READY state received by the vehicle control device 50 is READY-OFF (step S201, OFF), the process waits until the READY state changes to ON. On the other hand, if the READY state received by the vehicle control device 50 is READY-ON (step S201, ON), the process proceeds to step S202.

[0023] (Step S202) The vehicle control device 50 checks the synchronization processing status signals received from both the steering control device 20 and the steering wheel control device 30. Specifically, the vehicle control device 50 determines whether or not it has received synchronization completion signals from both the steering control device 20 and the steering wheel control device 30. This determination is made to determine whether or not the synchronization processing for controlling the steering angle of the steering wheel to coincide with the turning angle of the steered wheels has been completed normally. This determination is made periodically, for example, at predetermined intervals, similar to the determination of the READY state in step S201 above.

[0024] If the vehicle control device 50 receives synchronization completion signals from both the steering control device 20 and the steering wheel control device 30 (step S202, all completed), this power supply control ends. On the other hand, if the vehicle control device 50 has not yet received synchronization completion signals from both the steering control device 20 and the steering wheel control device 30 (step S202, either one is incomplete), the process proceeds to step S203.

[0025] (Step S203) The vehicle control device 50 determines whether the synchronization between the steering angle of the steering wheel and the turning angle of the steered wheels has not been completed for a predetermined time. Specifically, the vehicle control device 50 determines whether a predetermined time has elapsed since the READY state was READY-ON and the synchronization incompletion signal output from either the steering control device 20 or the steering wheel control device 30 was first recognized. This determination is made to reliably determine whether the vehicle is ready to travel when in a free-steering state in which the steering angle of the steering wheel and the turning angle of the steered wheels are not synchronized. The predetermined time can be appropriately set based on the time lag between the synchronization completion signals received by the vehicle control device 50 from the steering control device 20 and the steering wheel control device 30, the processing delay between the time the cruise control device 10 receives a start request signal and the time it transmits READY-ON, and the like.

[0026] If the vehicle control device 50 determines that the synchronization between the steering angle of the steering wheel and the turning angle of the steered wheels has not been completed for a predetermined time (Yes in step S203), the process proceeds to step S204. On the other hand, if the vehicle control device 50 determines that the synchronization between the steering angle of the steering wheel and the turning angle of the steered wheels has not been completed for a predetermined time (No in step S203), the process proceeds to step S201.

[0027] (Step S204) When the vehicle is in a free steering state, the vehicle control device 50 is in a state where the vehicle can travel, and therefore shuts off the ignition relay 40. Specifically, the vehicle control device 50 stops the drive output to the coil of the ignition relay 40, and opens the contacts of the ignition relay 40. This shutting off of the ignition relay 40 stops the power supply from the power supply unit 100 to the driving control device 10, and the operation of the driving control device 10 stops.

[0028] When the vehicle control device 50 turns off the ignition relay 40, this power supply control ends.

[0029] FIG. 3 shows an example of a sequence in a normal case where the vehicle is in a state where it cannot travel (READY-OFF) during a free-steering state in which the steering angle of the steering wheel and the turning angle of the steered wheels are not synchronized.

[0030] As shown in FIG. 3, if the vehicle does not become drivable between the time when the synchronization completion signals are received from the steering control device 20 and the steering wheel control device 30 and the time when the synchronization completion is determined, the vehicle control device 50 transitions to normal vehicle control while keeping the ignition relay 40 conductive.

[0031] FIG. 4 shows an example of a sequence in an abnormal case where the vehicle becomes ready to run (READY-ON) during a free-steering period in which the steering angle of the steering wheel and the turning angle of the steered wheels are not synchronized.

[0032] As shown in Fig. 4, if the vehicle becomes capable of running without receiving a synchronization completion signal from the steering wheel control device 30 (asynchronous), the vehicle control device 50 waits a predetermined time from the time when the synchronization incompletion signal is first received (from the steering wheel control device 30) and then controls the ignition relay 40 to be turned off. The ignition relay 40 is turned off by stopping the drive output to the coil, which in turn stops the operation of the cruise control device 10. This control makes it possible to prevent the vehicle from running unintentionally in a free steering state.

[0033] <Actions and Effects> As described above, according to the vehicle control device 50 according to one embodiment of the present disclosure, when the vehicle is in a state where it can be driven (READY-ON) before the synchronization process between the steering angle of the steering control device 20 and the steering angle of the steering wheels in the steering wheel control device 30 is completed, the ignition relay 40 is shut off and the power supply from the power supply unit 100 to the driving control device 10 is stopped (IG off control when synchronization is not completed).

[0034] By this control, in the unlikely event that a situation occurs in which the vehicle is able to travel during a period in which the steering angle of the steering wheel and the turning angle of the steered wheels are not synchronized due to a malfunction or the like, the operation of the travel control device 10 that controls the travel of the vehicle can be forcibly stopped, thereby preventing the vehicle from unintentionally traveling in a free steering state in which the steering operation is not reflected in the direction of the wheels (tires).In addition, by adopting this control, the scale of changes to the existing system of the vehicle can be minimized.

[0035] In the above power supply control, if the vehicle becomes ready to run while in a free-steering state in which the steering angle of the steering wheel and the turning angle of the steered wheels are not synchronized, the ignition relay 40 is controlled to be cut off after determining that a predetermined time has elapsed since the synchronization incomplete signal was first received (steps S203 to S204). However, in this case, there remains a significant possibility that the vehicle will run with steering wheel operation ineffective, so if the vehicle becomes ready to run while in a free-steering state, the ignition relay 40 may be controlled to be cut off immediately without waiting for the predetermined time to elapse.

[0036] <Application example> In the above embodiment, the vehicle equipped with the cruise control device 10, the steering control device 20, the steering wheel control device 30, the ignition relay 40, and the vehicle control device 50 is an electric vehicle. However, each of the above components can also be installed in a vehicle equipped with an internal combustion engine such as an engine. In this case, whether the vehicle is in a state where it can run can be determined not based on the READY state (READY-ON) but on the engine speed (for example, the speed is equal to or greater than a predetermined value) or an idle state signal indicating that the engine is under idling control.

[0037] In the above embodiment, the control for shutting off the ignition relay 40 to stop the power supply from the power supply unit 100 to the driving control device 10 has been described as a measure for preventing the vehicle from running. However, in addition to this measure, it is also possible to prevent the vehicle from running by, for example, having a system that controls the powertrain stop outputting driving force.

[0038] The above describes one embodiment of the present disclosure, but the present disclosure can be understood as not only a vehicle control device, but also a power supply control method executed by a vehicle control device having a processor and a memory, a control program for executing the power supply control method, a computer-readable non-transitory storage medium storing the control program, and a vehicle equipped with a vehicle control device. [Industrial Applicability]

[0039] The vehicle control device of the present disclosure can be used in a vehicle equipped with a steer-by-wire system that electrically controls steering. [Explanation of symbols]

[0040] 10 Driving control device 20 Steering control device 30 Steering wheel control device 40 Ignition relay 50 Vehicle control device 100 Power supply section

Claims

1. A vehicle control device mounted on a vehicle, a first determination unit that determines whether a steering angle of the steering wheel and a turning angle of the steered wheels are synchronized; a second determination unit that determines whether the vehicle is in a state where it can be driven; a control unit that controls power supply to a first device related to the running of the vehicle, the control unit stops the supply of power to the first device when the steering angle and the turning angle are not synchronized and the vehicle is in a travelable state. Vehicle control device.

2. the control unit stops the supply of power to the first device when the steering angle and the turning angle are not synchronized and the vehicle is in a drivable state for a predetermined time. The vehicle control device according to claim 1 .

3. the first determination unit determines that the steering angle and the turning angle are synchronized by receiving synchronization completion signals from both a second device that controls the steering and a third device that controls the steered wheels. The vehicle control device according to claim 1 or 2.

4. The control unit stops the power supply to the first device by shutting off an ignition relay inserted between a power supply unit and the first device. The vehicle control device according to any one of claims 1 to 3.

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