Vehicle control unit

Abstract

Vehicle control unit, including: a drive device (20) which applies a driving force to at least one drive wheel of wheels of a vehicle; a braking device (30) that applies a braking force to the wheels; a shift-changing device (40) that changes a shift position of a transmission (24) of the vehicle to one of positions that include a forward movement position, a reverse movement position and a park position; a steering device (50) that controls a steering angle of at least one steered wheel of the wheels; a control unit (10) configured to receive an assistance request generated by a portable device (82), and a parking assistance control consisting of (I.) a determination of a movement route along which the control unit (10) moves the vehicle from a present position of the vehicle to a predetermined target position in response to receiving the assistance request, and (II.) a control of activations of the drive device (20), the brake device (30), the shift-change device (40) and the steering device (50) to move the vehicle along the determined movement route; a first electrical power source device (200) which is installed in the vehicle; a second electrical power source device (210) installed in the vehicle; and an electrical power supply circuit (220) which, during the execution of the parking assistance control by the control unit (10), supplies electrical power from the first electrical power source device (200) to the drive unit (20), the brake device (30), the switching device (40), the steering device (50) and the control unit (10), if the first electrical power source device (200) is in a normal state, and, during the execution of the parking assistance control by the control unit (10), supplies electrical power from the second electrical power source device (210) to at least one of the brake device (30) and the switching device (40), if a malfunction occurs in the first electrical power source device (200), wherein the control unit (10) is configured to set a target speed of the vehicle during the execution of the parking support control by the control unit (10) such that a maximum value of the target speed is a first speed, characterized by the fact that the control unit (10) is configured to perform the parking assistance control by maintaining the vehicle's speed at a speed slower than or equal to a predetermined speed limit slower than the first speed during the execution of the parking assistance control by the control unit (10), if the control unit (10) determines that a predetermined condition, namely that the vehicle is moving along a downhill slope, is met based on an index value representing a degree of gradient of a road along which the vehicle is moving, if the first electrical power source device (200) is in the normal state, at least one of the brake device (30) and the switching device (40) is equipped to perform a stop control of a stopping of the vehicle during the execution of the parking support control by the control unit (10) if the malfunction occurs in the first electrical power source device (200), the switching device (40) is configured to be able to change the switching position to the park position if the speed of the vehicle is slower than or equal to a predetermined speed threshold; the predetermined speed limit is lower than the predetermined speed threshold; and the switching change device (40) is configured to perform a switching control of changing the switching position to the park position as the stop control if the malfunction occurs in the first electrical power source device (200) while the control unit (10) is performing the parking support control.

Description

BACKGROUND OF THE INVENTION Technical field

[0001] The invention relates to a vehicle control unit. State of the art

[0002] A vehicle control unit has been proposed that performs a parking assistance control of moving a vehicle to a set target area depending on the vehicle's environmental situation (see, for example, publication JP 2015 - 101 225 A).

[0003] The vehicle control unit proposed in publication JP 2015-101225A (hereinafter referred to as "the conventional unit") is configured to execute the parking assistance control even when a driver is outside the vehicle. This control is also referred to as the remote parking assistance control. The driver exits the vehicle and operates a remote control or transmission device. The remote control sends a signal to the conventional unit, causing it to initiate an execution of the parking assistance control in response to an action applied by the driver to the remote control. Upon receiving this signal, the conventional unit determines whether the amount of electrical power remaining in an electrical power source or battery provided in the vehicle is less than or equal to a predetermined threshold.If the remaining electrical power is less than or equal to the predetermined threshold, the conventional device shifts a transmission to neutral. If this prevents an internal combustion engine from starting due to insufficient electrical power stored in the electrical power source, the driver can move the vehicle by applying an external force.

[0004] Furthermore, JP 2020 - 104 529 A discloses a control unit configured to monitor an electrical charge quantity of an electrical energy source after at least one control unit begins to execute a parking aid control, and to execute a stop control of a control of at least one of the braking device and the speed change device to stop the vehicle when the electrical charge quantity of the electrical energy source becomes less than a predetermined first threshold.Furthermore, US 2018 / 0 022 329 A1 describes a control unit for performing a parking aid by maintaining the vehicle's speed at a level less than or equal to a predetermined speed limit when it is determined that a predetermined condition—that the vehicle is traveling downhill—is met, based on an index value representing the gradient of the road on which the vehicle is traveling when an electrical power source is in normal operation. Additionally, US 2018 / 0 093 662 A1 discloses a parking aid that modifies the vehicle's controls to drive to the target parking position when the detected driving resistance is equal to or greater than a predetermined resistance.

[0005] Malfunctions or faults can occur in the electrical power source while the remote parking assist control is operating. The conventional device does not address such malfunctions or faults. For example, if the vehicle is being moved down a slope by the remote parking assist control and a malfunction occurs in the electrical power source, the driver will be outside the vehicle. Therefore, the driver cannot operate the vehicle's brake pedal. Consequently, the vehicle may continue to move.

[0006] To solve such problems, one solution is to provide the vehicle with a secondary electrical power source in addition to a primary one, and to stop the vehicle using the electrical power from the secondary source if a fault occurs in the primary power source. However, even when such a solution is used, the time until the vehicle stops may be longer, the distance required to stop the vehicle may be longer, or the vehicle may continue moving without being stopped. INVENTION SUMMARY

[0007] Accordingly, it is an object of the invention to provide a vehicle control unit that can easily stop the vehicle if a malfunction occurs in the electrical power source while the vehicle is moving along a road with a gradient (for example, a downward slope).

[0008] The problem is solved according to the invention by a vehicle control unit according to claim 1 and alternatively by a vehicle control unit according to claim 6. Further features and advantageous embodiments are shown in the dependent claims.

[0009] A vehicle control unit according to the invention comprises a drive unit, a brake unit, a switching unit, a steering unit, a control unit, a first electrical power source device, a second electrical power source device and an electrical power supply circuit.

[0010] The drive unit applies a driving force to at least one drive wheel of a vehicle. The brake unit applies a braking force to the wheels. The gearshift unit changes the gear position of the vehicle's transmission to one of several positions, including forward, reverse, and park. The steering unit controls the steering angle of at least one steered wheel.

[0011] The control unit is configured to receive a support request generated by a portable device and to execute a parking support control consisting of (I.) determining a movement route along which the control unit moves the vehicle from a current position of the vehicle to a predetermined target position in response to receiving the support request, and (II.) controlling activations of the drive unit, brake unit, shift unit and steering unit to move the vehicle along the determined movement route.

[0012] The first electrical power source device is installed in the vehicle. The second electrical power source device is also installed in the vehicle.

[0013] During the execution of the parking assist control by the control unit, the electrical power supply circuit supplies electrical power from the first electrical power source device to the drive unit, the brake unit, the shift unit, the steering unit, and the control unit, provided the first electrical power source device is in a normal state. If a malfunction occurs in the first electrical power source device, the electrical power supply circuit supplies electrical power from the second electrical power source device to at least one of the brake unit and the shift unit during the execution of the parking assist control by the control unit.

[0014] The control unit is designed to set a target speed for the vehicle during the execution of the parking support control by the control unit, such that a maximum value of the target speed is a first speed.

[0015] The control unit is configured to perform the parking assistance control by maintaining the vehicle's speed at a speed slower than or equal to a predetermined speed limit slower than the first speed, if the control unit determines that a predetermined condition of the vehicle moving along a downhill slope is met, based on an index value representing the degree of gradient of a road along which the vehicle is moving, assuming the first electrical power source device is in its normal state.

[0016] At least one of the brake device and the switching device is equipped to perform a stop control of a stopping of the vehicle during the execution of the parking support control by the control unit, if a malfunction occurs in the first electrical power source device.

[0017] According to the invention, at the time the malfunction occurs in the first electrical power source device, the vehicle moves at the predetermined speed limit or less if the malfunction occurs while the vehicle is moving downhill. This allows the vehicle control unit to easily stop the vehicle using the stop control. This eliminates the risk of the vehicle continuing to move without stopping, or of the time or distance required to stop being increased.

[0018] According to the invention, the switching device is configured to change the switching position to the park position if the vehicle's speed is slower than or equal to a predetermined speed threshold. In this embodiment, the predetermined speed limit can be lower than the predetermined speed threshold. Furthermore, in this embodiment, the switching device can be configured to perform a switching control of changing the switching position to the park position as a stop control if a malfunction occurs in the first electrical power source device while the control unit is executing the parking assist control.

[0019] According to this embodiment of the invention, the predetermined speed limit is lower than the predetermined speed threshold at which the shift control device can change the switching position to the park position. Thus, the shift control device can stop the vehicle by executing the shift control.

[0020] According to another embodiment of the invention, the first speed can be slower than the predetermined speed threshold.

[0021] According to a further embodiment of the invention, the control unit can be configured to set the predetermined speed limit such that the predetermined speed limit decreases with an increase in the degree of the gradient of the downward slope, if the predetermined condition is met.

[0022] The vehicle cannot be stopped easily if the gradient of the downhill slope is steep. According to this embodiment of the invention, the predetermined speed limit is set to a value that decreases as the gradient of the downhill slope increases.

[0023] Therefore, the vehicle control unit can easily stop the vehicle by executing the stop control.

[0024] According to a further embodiment of the invention, the brake device can perform a brake force control of applying brake force to the wheels as the stop control, and the shift-change device can perform a shift control of changing the shift position to the park position as the stop control if the malfunction occurs in the first electrical power source device while the control unit is performing the parking assist control. In this embodiment, the shift-change device can be configured to begin executing the shift control after the brake device begins executing the brake force control.

[0025] According to this embodiment of the invention, if a malfunction occurs in the first electrical power source device, the braking device begins to execute the braking control of decelerating the vehicle before the switching device executes the switching control. Thus, the switching device can execute the switching control while the vehicle has decelerated. This allows the vehicle control unit to bring the vehicle to a safe stop.

[0026] According to a further embodiment of the invention, the first electrical power source device can have a first electrical capacitance. In this embodiment, the second electrical power source device can have a second electrical capacitance that is smaller than the first electrical capacitance.

[0027] A vehicle control unit according to a further invention comprises a drive unit, a brake unit, a switching unit, a steering unit, a control unit, a first electrical power source device, a second electrical power source device and an electrical power supply circuit.

[0028] The drive unit applies a driving force to at least one drive wheel of a vehicle. The brake unit applies a braking force to the wheels. The gearshift unit changes the gear position of the vehicle's transmission to one of several positions, including forward, reverse, and park. The steering unit controls the steering angle of at least one steered wheel.

[0029] The control unit is designed to perform autonomous driving control of activations of the drive unit, the brake unit, the shift change unit and the steering unit.

[0030] The first electrical power source device is installed in the vehicle. The second electrical power source device is also installed in the vehicle.

[0031] During the execution of the parking assist control by the control unit, the electrical power supply circuit supplies electrical power from the first electrical power source device to the drive unit, the brake unit, the shift-change unit, the steering unit, and the control unit, provided the first electrical power source device is in a normal state. If a malfunction occurs in the first electrical power source device, the electrical power supply circuit supplies electrical power from the second electrical power source device to at least one of the brake unit and the shift-change unit during the execution of the parking assist control by the control unit.

[0032] The control unit is designed to move the vehicle to a predetermined target speed by controlling the vehicle's speed, while the control unit performs the parking assistance control.

[0033] The control unit is configured to execute the parking assistance control by maintaining the vehicle's speed at a speed slower than or equal to a predetermined speed limit that is slower than the predetermined target speed, if the control unit determines that the predetermined condition of the vehicle moving along a downhill slope is met, based on an index value representing a degree of gradient of a road along which the vehicle is moving, assuming the first electrical power source device is in a normal state.

[0034] At least one of the braking device and the switching device is equipped to perform a stop control of a stopping of the vehicle during the execution of autonomous driving control by the control unit if a malfunction occurs in the first electrical power source device.

[0035] The switching device is configured to change the gear position to the park position if the vehicle's speed is less than or equal to a predetermined speed threshold. In this configuration, the predetermined speed limit can be lower than the predetermined speed threshold. Furthermore, in this configuration, the switching device can be configured to perform a switching control of changing the gear position to the park position as a stop control if a malfunction occurs in the first electrical power source device while the control unit is executing the parking assist control.

[0036] According to another embodiment of the invention, the control unit can be a microprocessor programmed to execute one or more of the functions described in this specification. According to yet another embodiment of the invention, the control unit can be implemented wholly or partially by hardware, for example, by integrated circuits such as ASICs, dedicated to one or more applications. For the purposes of this description, components of an embodiment described below are designated, for the sake of clarity, by reference numerals enclosed in parentheses, as used in the description of the embodiment. However, the components of the invention are not limited to those defined by the reference numerals of the embodiment.The further objects, features and accompanying advantages of the invention are easily understood from the following description of the embodiments of the invention together with the drawing. BRIEF DESCRIPTION OF THE DRAWING Fig. Figure 1 shows a representation illustrating a general configuration of a vehicle control unit according to an embodiment of the invention. Fig. Figure 2 shows a representation illustrating a connection relationship between components of the vehicle control unit according to Fig. 1 and electrical power source devices illustrated (a first electrical power source device and a second electrical power source device) that are fitted in a vehicle. Fig. Figure 3 shows a representation illustrating a configuration of a selection circuit according to Fig. 2 illustrated. Fig. Figure 4 shows a representation illustrating an example of a change in a final target speed Vtgt over time as the vehicle moves to a target position Ptgt from a starting position Pst at which an execution of the parking assist control was initiated. Fig. Figure 5 shows a representation illustrating another example of the change in final target speed Vtgt over time as the vehicle moves to the target position Ptgt from the starting position Pst, where an execution of the parking assist control was initiated. Fig. Figure 6 shows a diagram illustrating a flowchart of a dual parking assistance execution routine performed by a CPU of a parking assistance ECU. Fig. Figure 7 shows a diagram illustrating a flowchart of a target speed setting routine, which occurs at step 608 of a dual parking assist execution routine according to Fig. 6 is executed by the CPU of the parking assist ECU. Fig. Figure 8 shows a diagram illustrating a flowchart of an initial control execution routine performed by a CPU of a brake ECU. Fig. Figure 9 shows a diagram illustrating a flowchart of a second control execution routine performed by a CPU of an SBW-ECU. Fig. Figure 10 shows a representation illustrating a first map M1 that defines a relationship between a gradient angle θ of a road and a speed limit Vs_lim. Fig. Figure 11 shows a representation illustrating a second map M2 that defines the relationship between the gradient angle θ of the road and the speed limit Vs_lim. DESCRIPTION OF THE EXAMPLES OF EXECUTION

[0037] According to one embodiment of the invention, a vehicle control unit is installed in a vehicle. For the purpose of distinguishing it from other vehicles, the vehicle with the installed vehicle control unit can be referred to as the "own vehicle". Fig. 1 The vehicle comprises a parking assistance ECU 10, a drive unit 20, a brake unit 30, a shift change unit 40 and a steering unit 50.

[0038] In this description, ECU stands for Electronic Control Unit. The ECU comprises a microcomputer that includes a CPU, RAM, ROM, and an interface. The CPU performs various functions by executing instructions stored in the ROM. For example, the parking assist ECU 10 comprises a microcomputer with a CPU 10a, RAM 10b, ROM 10c, and an interface (I / F) 10d.

[0039] The parking assistance ECU 10 is electrically connected to send and receive information to and from other ECUs (e.g., various ECUs 21, 31, 41, 51, 71 and 72 described below) via a CAN (control area network) 90.

[0040] The drive unit 20 generates a driving force and applies the generated driving force to the drive wheels of a vehicle (e.g., a left front wheel, a right front wheel, a left rear wheel, and a right rear wheel). The drive unit 20 comprises a machine 21, machine actuators 22, an internal combustion engine 23, a transmission 24, and a (not shown) driving force transmission mechanism that transmits the driving force to the drive wheels. The machine ECU 21 is electrically connected to the machine actuators 22. The machine actuators 22 include a throttle valve actuator for changing the opening degree of a throttle valve of the internal combustion engine 23. The machine ECU 21 can modify a torque generated by the internal combustion engine 23 by activating the machine actuators 22.The torque generated by the internal combustion engine 23 is transmitted to the drive wheels via the gearbox 24 and the drive force transmission mechanism. Thus, the machine ECU 21 can control the drive force applied to the vehicle by controlling the activation of the machine actuators 22. Hereinafter, the torque generated by the internal combustion engine 23 is referred to as the "drive torque".

[0041] It should be noted that if the vehicle is a hybrid vehicle, the machine ECU 21 can control the tractive force generated by one or both of the internal combustion engines and at least one electric motor as vehicle propulsion power sources. Furthermore, if the vehicle is an electric vehicle, the machine ECU 21 can control the tractive force generated by at least one electric motor as the vehicle propulsion power source.

[0042] The braking device 30 applies a braking force to the wheels. The braking device 30 comprises a brake ECU 31, brake actuators 32, and wheel cylinders 33. The brake ECU 31 is electrically connected to the brake actuators 32. The brake actuators 32 comprise known hydraulic circuits, a reservoir (not shown), an oil pump (not shown), and various valve systems (not shown). The brake actuators 32 establish a hydraulic pressure (i.e., a brake pressure) that is applied to the wheel cylinders 33 in response to instructions from the brake ECU 31. Friction braking forces generated at the wheels change depending on the brake pressure. Thus, the brake ECU 31 can control the braking force applied to the vehicle by controlling the activation of the brake actuators 32.

[0043] The shift-change device 40 changes a shift position (a gear stage) of the transmission 24. In this embodiment, the shift position comprises at least a park position, a neutral position, a forward position, and a reverse position. When the shift position is set to the park position, the shift-change device 40 stops the transmission of drive power to the drive wheels and mechanically locks the wheels to prevent them from rotating. In particular, when the shift position is set to the park position, an output shaft of the transmission 24 is locked to prevent the output shaft from rotating. Such a condition is also referred to as a "park lock state" or "P lock state." When the shift position is set to the neutral position, the shift-change device 40 does not transmit drive power to the drive wheels.However, if the shift position is set to the neutral position, the shift change device 40 does not mechanically lock the wheels. If the shift position is set to the forward movement position, the shift change device 40 transmits the drive force to the drive wheels as the drive force for moving the vehicle forward. If the shift position is set to the reverse movement position, the shift change device 40 changes the drive force to the drive wheels as the drive force for moving the vehicle backward.

[0044] The shift-by-wire unit 40 comprises an SBW-ECU (or “shift-by-wire” ECU, ECU for wired shifting) 41, a shift lever sensor 42, an SBW actuator (SBW-Act) 43, and a shift-by-wire mechanism 44. The SBW-ECU 41 is electrically connected to the shift lever sensor 42 and the SBW actuator 43. The shift lever sensor 42 detects the position of the shift lever. The SBW-ECU 41 receives the position of the shift lever from the shift lever sensor 42 and controls activations of the SBW actuator 43 based on the received position of the shift lever. The SBW actuator 43 controls activations of the shift change mechanism 44 in response to instructions from the SBW-ECU 41, and changes the shift position of the transmission 24 to one of the shift positions (the park position, the neutral position, the forward movement position and the reverse movement position).

[0045] Specifically, the SBW-ECU 41 activates the SBW actuator 43 to control the activation of the shift mechanism 44 in order to move the transmission 24 to the park position if the shift lever is in the "P" position. If the shift lever is in the "N" position, the SBW-ECU 41 activates the SBW actuator 43 to control the activation of the shift mechanism 44 in order to move the transmission 24 to the neutral position. If the shift lever is in the "D" position, the SBW-ECU 41 activates the SBW actuator 43 to control the activation of the shift mechanism 44 in order to move the transmission 24 to the forward position. If the position of the shift lever is “R”, the SBW-ECU 41 activates the SBW actuator 43 to control the activation of the shift change mechanism 44 in order to control the shift position of the transmission 24 to the reverse movement position.It should be noted that the SBW-ECU 41 outputs a signal to the parking support ECU 10 regarding the position of the gear lever received from the gear lever sensor 42.

[0046] It should also be noted that the SBW-ECU 41 can change the shift position of the transmission 24 from a position other than the park position to the park position if the vehicle speed Vs is zero, as well as if the vehicle speed Vs is less than or equal to a predetermined speed threshold Vsth (for example, 3 km / h).

[0047] The steering device 50 controls the steering angle of the steered wheels (the left front wheel and the right front wheel). The steering device 50 comprises an electric power steering ECU (hereinafter referred to as the "EPS ECU") 51, an assist motor (M) 52, and a steering mechanism 53. The EPS ECU 51 is electrically connected to the assist motor 52. The assist motor 52 is housed within the steering mechanism 53. The steering mechanism 53 is a mechanism that steers the steered wheels in response to an input of a rotation of a steering wheel SW. The steering mechanism 53 comprises the steering wheel SW, a steering shaft US connected to the steering wheel SW, and a steering gear mechanism (not shown). The EPS ECU 51 detects a steering torque input from a driver to the steering wheel SW using a steering torque sensor (not shown) provided on the steering shaft US and activates the assist motor 52 based on the detected steering torque.The EPS-ECU 51 applies a steering torque (a steering support torque) to the steering mechanism 53 by activating the support motor 52 in order to assist steering actions performed by the driver.

[0048] Furthermore, as described below, the parking assistance ECU 10 sends steering instructions to the assistance motor 52 if parking assistance control is performed as described below. If the EPS ECU 51 receives the steering instruction from the parking assistance ECU 10 via CAN 90, the EPS ECU 51 activates the assistance motor 52 based on the steering torque specified by the steering instruction to change the steering angle of the vehicle's steered wheels.

[0049] The parking assistance ECU 10 is electrically connected to environmental sensors 60. The environmental sensors 60 acquire vehicle environment information. This vehicle environment information includes (I.) information about objects around the vehicle and (II.) information about lane markings on the road around the vehicle. For example, the objects include moving objects such as cars, pedestrians, and bicycles, and stationary objects such as guardrails and fences. The environmental sensors 60 include ultrasonic wave sensors 61 and cameras 62.

[0050] The ultrasonic wave sensor 61 emits ultrasonic waves in a pulsed manner to a predetermined area around the vehicle and receives reflected waves that are reflected by objects. The ultrasonic wave sensor 61 can (I.) detect reflection points on the object from which the emitted ultrasonic waves are reflected, and (II.) determine the distance between the ultrasonic wave sensor 61 and the object based on the time from when the ultrasonic wave sensor 61 emits the ultrasonic wave until when the ultrasonic wave sensor 61 receives the reflected ultrasonic wave.

[0051] Camera 62 is a digital camera comprising imaging elements such as a CCD (charge-coupled device) or a CIS (or CMOS) image sensor. Camera 62 acquires image data about the surrounding environment, including (I.) the positions and shapes of objects, and (II.) the positions and shapes of lane markings around the vehicle, which are to be checked for parking the vehicle in or out of a parking space. Camera 62 outputs the acquired image data to the parking assistance ECU 10.

[0052] The parking assistance ECU 10 receives detection signals from the ultrasonic wave sensors 61 each time a predetermined time (hereinafter referred to as the "first time" for simplicity) dT1 elapses. The parking assistance ECU 10 plots the information contained in the detection signals (i.e., the positions of the reflection points from which the ultrasonic waves are reflected) on a two-dimensional map. The two-dimensional map is a planar view that defines the vehicle's position as an origin, the vehicle's direction of movement on an X-axis, and a counterclockwise direction on a Y-axis. It should be noted that the vehicle's position is a position corresponding to a predetermined midsection of the vehicle in a top-down view.The Parking Assistance ECU 10 detects objects around the vehicle based on the shapes of a group of reflection points on the two-dimensional map. The Parking Assistance ECU 10 provides the position (distance and orientation) of the detected object relative to the vehicle. Additionally, the Parking Assistance ECU 10 provides the shape of the detected object.

[0053] It should be noted that the position of the vehicle is another predetermined position of the vehicle such as (I.) a position which, in a plan view, corresponds to a midsection between the left front wheel and the right front wheel, or (II.) a position which, in a plan view, corresponds to a midsection between the left rear wheel and the right rear wheel, or (III.) a position which, in a plan view, corresponds to a geometric midsection of the vehicle.

[0054] Additionally, the parking assistance ECU 10 acquires image data from cameras 62 each time the first time interval dT1 expires. The parking assistance ECU 10 detects objects around the vehicle by analyzing the image data and provides their positions (distances and orientations) and shapes relative to the vehicle. Based on the image data, the parking assistance ECU 10 plots the specified and detected objects onto the two-dimensional map. Thus, the parking assistance ECU 10 can detect objects around the vehicle (within a predetermined distance range from the vehicle) based on the information displayed on the two-dimensional map.

[0055] Based on the information displayed on the two-dimensional map, the Parking Assistance ECU 10 detects an area around the vehicle free of objects. If this area is of a size and shape sufficient for parking or re-parking the vehicle, the Parking Assistance ECU 10 designates it as a permitted parking area or re-parking area. It should be noted that when boundary lines defining a parking space around the vehicle are detected, the permitted parking area has (I.) a rectangular shape within the boundary lines, (II.) long sides that are one span longer than the longitudinal length of the vehicle, and (III.) short sides that are a second span longer than the lateral length of the vehicle.

[0056] Additionally, the parking assistance ECU 10 is electrically connected to an acceleration sensor 63 and wheel speed sensors 64. The acceleration sensor 63 detects the longitudinal acceleration Gx of the vehicle and outputs a signal representing this acceleration Gx to the parking assistance ECU 10. The wheel speed sensors 64 are located at each wheel (left front wheel, right front wheel, left rear wheel, and right rear wheel) and output signals representing the angular velocities of the wheels to the parking assistance ECU 10. Based on the signals from the wheel speed sensors 64, the parking assistance ECU 10 calculates the vehicle speed Vs (a movement speed).

[0057] The acceleration sensor 63 and the wheel speed sensors 64 detect information about the vehicle's state of motion. Therefore, the acceleration sensor 63 and the wheel speed sensors 64 can be referred to collectively as "state of motion sensors" below.

[0058] Additionally, the parking assistance ECU 10 is electrically connected to a collation ECU 71 and a communication ECU 72. The collation ECU 71 is configured to wirelessly send and receive information to and from a smart key 81. The smart key 81 has a stored identifier used to identify the vehicle. This identifier is referred to below as the "ID". Similarly, the ID used to identify the vehicle is stored in a ROM of the collation ECU 71. The collation ECU 71 determines whether the ID sent by the smart key 81 matches the ID stored in its ROM. If the ID sent by the smart key 81 matches the ID stored in its ROM, the collation ECU 71 outputs a signal indicating the completion of user authentication to the parking assistance ECU 10.The signal indicating the completion of user authentication is referred to below as an "authentication completion signal".

[0059] The communication ECU 72 is configured to wirelessly send and receive information to and from a portable device 82. The portable device 82 is, for example, a smartphone. Application software dedicated to parking assistance control is installed on the portable device 82. Hereinafter, the application software dedicated to parking assistance control is referred to as the "parking application." Parking assistance control is a known control system for autonomously moving the vehicle to a predefined target area based on the vehicle's surroundings. When the driver performs a predetermined action on or within the parking application, the portable device 82 wirelessly transmits an assistance request signal to the communication ECU 72 to request assistance with parking or maneuvering out of a parking space.If the communication ECU 72 receives the assistance request signal from the portable device 82, the communication ECU 72 outputs the assistance request signal to the parking assistance ECU 10. Additionally, the portable device 82 receives a display instruction from the parking assistance ECU 10 via the communication ECU 72. Based on the received display instruction, the portable device 82 displays various information regarding the parking assistance control on a display on the portable device 82. <Inhalte der Parkunterstützungssteuerung>

[0060] A user (the driver) sends the assistance request signal to the parking assistance ECU 10 via the communication ECU 72 by performing the predetermined action in the parking application. Additionally, an assistance operating mode is set by the parking application, either as a parking mode or as an exit mode. The assistance operating mode can be set by the user or can be set automatically depending on the vehicle's condition and the surrounding environment. Thus, the assistance request signal includes information about the assistance operating mode.

[0061] The parking mode includes a double parking mode and a parallel parking mode. The double parking mode is an operating mode for assisting with double parking or double-row parking of the vehicle. Double parking means parking the vehicle perpendicular to the direction of travel on a road. Specifically, double parking means parking the vehicle such that (I.) one side of the vehicle faces the side of another vehicle (first vehicle), (II.) the other side of the vehicle faces the side of a third vehicle (second vehicle), and (III.) the longitudinal centerline of the vehicle is parallel to the longitudinal centerlines of the first and second vehicles.

[0062] Parallel parking mode is an operating mode for providing parking assistance when parking a vehicle parallel to the road. Parallel parking means parking the vehicle so that it is parallel to the direction of travel. Specifically, parallel parking means parking the vehicle such that (I.) the front of the vehicle faces the front or rear of the first vehicle, (II.) the rear of the vehicle faces the front or rear of the second vehicle, and (III.) the longitudinal centerline of the vehicle aligns with the longitudinal centerlines of the first and second vehicles.

[0063] The parking exit mode is an operating mode for supporting the removal of the parked vehicle from the parking space, i.e., moving the parked vehicle onto the road.

[0064] If the parking mode (dual parking mode or parallel parking mode) is set to the assistance mode, the parking assistance ECU 10 defines a target area as an area occupied by a body of the vehicle if the parking assistance ECU 10 parks the vehicle in the permitted parking area. Additionally, the parking assistance ECU 10 sets a target position Ptgt to a position of the vehicle at which it is parked within the target area. The target position Ptgt is a position that a central section of the vehicle should reach in a top view.

[0065] The parking assistance ECU 10 calculates a movement route along which it moves the vehicle from a starting position Pst (i.e., the current position) to the target position Ptgt, where the parking assistance ECU 10 begins executing parking assistance control. The movement route allows the parking assistance ECU 10 to move the vehicle from the starting position Pst to the target position Ptgt, maintaining a predetermined interval or more between the vehicle body and objects such as other vehicles, curbs, and guardrails. It should be noted that the parking assistance ECU 10 calculates the movement route using one of several known computational methods (for example, a method proposed in publication JP 2015-3536A).

[0066] If the parking assistance ECU 10 determines the movement route, the parking assistance ECU 10 determines a direction of movement of the vehicle (in particular, the shift position of the transmission 24), a steering angle pattern and a speed pattern for movement of the vehicle along the movement route.

[0067] Depending on the specified shift position, the parking support ECU 10 sends a shift control instruction to the SBW ECU 41 via CAN 90. If the SBW ECU 41 receives the shift control instruction from the parking support ECU 10, the SBW ECU 41 executes a shift control action by activating the SBW actuator 43 to change the shift position of the transmission 24 to a position specified by the received shift control instruction.

[0068] The steering angle pattern comprises data that associates the vehicle's position along the movement path with the steering angle of the steered wheels. The steering angle pattern represents changes in the steering angle as the vehicle moves along the movement path. Depending on the specific steering angle pattern, the parking assist ECU 10 sends a steering instruction with a target steering angle to the EPS ECU 51 via CAN 90. If the EPS ECU 51 receives the steering instruction from the parking assist ECU 10, it performs steering angle control based on the steering torque specified by the received steering instruction, activating the assist motor 52 to control the actual steering angle to the target steering angle.

[0069] The speed pattern comprises data that associates the vehicle's position on the movement route with a target speed Vsa. The speed pattern represents changes in the target speed Vsa as the vehicle moves along the movement route. According to the speed pattern, the target speed Vsa gradually increases to an initial speed Vs1 after the starting position Ptgt. Once the target speed Vsa reaches the initial speed Vs1, it is maintained at that initial speed. Subsequently, the target speed Vsa gradually decreases as the vehicle approaches the target position Ptgt. If the vehicle reaches the target position Ptgt, the target speed Vsa becomes zero.Thus, the parking assistance ECU 10 sets the target speed Vsa such that a maximum value of the target speed Vsa in the speed pattern corresponds to the first speed Vs1. Therefore, the vehicle is moved at a speed lower than or equal to the first speed Vs1 while the parking assistance control is executed. In this embodiment, the first speed Vs1 is lower than or equal to the predetermined speed threshold Vsth.

[0070] As the vehicle moves along the route, the parking assist ECU 10 sets a final target speed Vtgt using the speed pattern. Depending on the final target speed Vtgt, the parking assist ECU 10 sends a drive force control instruction to the machine ECU 21 via CAN 90. If the machine ECU 21 receives the drive force control instruction from the parking assist ECU 10, it executes a drive force control action, controlling the activation of the machine actuators 22. Additionally, depending on the final target speed Vtgt, the parking assist ECU 10 sends a brake force control instruction to the brake ECU 31 via CAN 90.If the brake ECU 31 receives the brake force control instruction from the parking support ECU 10, the brake ECU 31, in response to the received brake force control instruction, performs brake force control by controlling the activations of the brake actuators 32.

[0071] Even if the parking assist mode is set to the support mode, the parking assist ECU 10 executes the parking assist control in a manner similar to that described above. The parking assist ECU 10 determines an area within the permitted parking assist area as the target area and sets a position within the target area as the target position Ptgt, which corresponds to the position the parked vehicle will ultimately reach. The parking assist ECU 10 calculates the movement route along which it moves the vehicle from the starting position Pst, where it begins executing the parking assist control, to the target position Ptgt. Subsequently, the parking assist ECU 10 determines the vehicle's direction of movement, steering angle pattern, and speed pattern for moving the vehicle along the movement route.Subsequently, based on the specific direction of movement of the vehicle, the specific steering angle pattern and the specific speed pattern, the parking assistance ECU 10 performs the shift control, the steering angle control, the drive force control and the brake force control.

[0072] According to the above description, the parking assistance ECU 10 is configured to perform, as the parking assistance control, the shift control of changing the shift position of the transmission 24, the steering angle control of changing the steering angle of the steered wheels, the drive force control of controlling the drive force applied to the vehicle, and the brake force control of controlling the brake force applied to the vehicle, if the driver is outside the vehicle. <Redundante Konfiguration einer elektrischen Leistungsquelle>

[0073] According to Fig. 2 the vehicle is provided with a first electrical power source device 200, a second electrical power source device 210 and an electrical power supply circuit 220.

[0074] The first electrical power source device 200 comprises a first capacitor section 201 and a first electrical power control section 202. The first capacitor section 201 is a capacitor element that can be charged and discharged. The first capacitor section 201 is, for example, a secondary battery. The secondary battery can be a lithium-ion battery or a nickel-hydride battery. The first capacitor section 201 has a first electrical power source capacitance. The first electrical power control section 202 comprises (I.) a charge / discharge circuit that controls the charging and discharging operations of the first capacitor section 201, (II.) an ECU that controls the activation of the charge / discharge circuit, and (III.) a known gain / attenuation circuit.It should be noted that the ECU of the first electrical power control section 202 is activated by electrical power from the first capacitor section 201. The first electrical power control section 202 is configured to adjust an output voltage from the first capacitor section 201 to a predetermined constant first voltage V1, which is higher than zero.

[0075] The second electrical power source device 210 is an electrical power source used if a malfunction or fault occurs in the first electrical power source device 200 during the execution of the parking assist control. The second electrical power source device 210 comprises a second capacitor section 211 and a second electrical power control section 212. The second capacitor section 211 is a capacitor element that can be charged and discharged. The second capacitor section 211 comprises one or more capacitors. For example, the second capacitor section 211 can be a double-layer electrical capacitor. The second capacitor section 211 has a second electrical power source capacitance.For the purpose of reducing the load size and cost of the vehicle, the second electrical power capacity of the second capacitor section 211 is smaller than the first electrical power capacity of the first capacitor section 201.

[0076] With this configuration, the second capacitor section 211 is set up to be charged by the electrical power of the first capacitor section 201 if the first electrical power source device 200 is activated normally. It should be noted that the second capacitor section 211, like the first capacitor section 201, can be a secondary battery.

[0077] The second electrical power control section 212 comprises (I.) a charging / discharging circuit that controls the charging and discharging operations of the second capacitor section 211, (II.) an ECU that controls the activation of the charging / discharging circuit, and (III.) a known gain / attenuation circuit. It should be noted that the ECU of the second electrical power control section 212 is activated by the electrical power of the second capacitor section 211. The second electrical power control section 212 is configured to adjust an output voltage of the second capacitor section 211 to a predetermined constant second voltage V2, which is higher than zero. The predetermined constant second voltage V2 is lower than the predetermined constant first voltage V1.

[0078] Additionally, the ECU of the second electrical power control section 212 can detect a malfunction of the second capacitor section 211. If the ECU of the second electrical power control section 212 initiates a parking assist control operation, it determines whether a malfunction is occurring in the second capacitor section 211. For example, if the voltage of the capacitor in the second capacitor section 211 is less than or equal to a predetermined voltage, the electrical power of the second capacitor section 211 is insufficient, and the ECU of the second electrical power control section 212 determines that a malfunction is occurring in the second capacitor section 211.If the malfunction occurs in the second capacitor section 211, the ECU of the second electrical power control section 212 informs the parking support ECU 10 via CAN 90 that a malfunction occurs in the second capacitor section 211.

[0079] The electrical power supply circuit 220 comprises an electrical power source redundancy circuit 230, a first electrical power source line 240, and a second electrical power source line 250. The first electrical power source line 240 extends from the first electrical power source device 200 and is electrically connected to the parking assist ECU 10, the drive unit 20, the steering unit 50, and the electrical power source redundancy circuit 230. The second electrical power source line 250 extends from the second electrical power source device 210 and is electrically connected to the electrical power source redundancy circuit 230.

[0080] According to Fig. 2 The first electrical power source redundancy circuit 230 comprises a first selection circuit 231-1 and a second selection circuit 231-2. The first selection circuit 231-1 and the second selection circuit 231-2 are each configured to selectively output the electrical power supplied by the first capacitor section 201 via the first electrical power source line 240 or the electrical power supplied by the second capacitor section 211 via the second electrical power source line 250. According to Fig. 3 are the first selection circuit 231-1 and the second selection circuit 231-2 diode-OR circuits.

[0081] The first selector circuit 231-1 comprises (I.) a first diode 301-1, which has an anode electrically connected to the first power source line 240, and (II.) a second diode 302-1, which has an anode electrically connected to the second power source line 250. A cathode of the first diode 301-1 and a cathode of the second diode 302-1 are electrically connected to an output end 231a-1 of the first selector circuit 231-1. The output end 231a-1 of the first selector circuit 231-1 is electrically connected to an output line 260-1. The output line 260-1 is electrically connected to the brake device 30.

[0082] The second selector circuit 231-2 comprises (I.) a first diode 301-2, which has an anode electrically connected to the first power source line 240, and (II.) a second diode 302-2, which has an anode electrically connected to the second power source line 250. A cathode of the first diode 301-2 and a cathode of the second diode 302-2 are electrically connected to an output end 231a-2 of the second selector circuit 231-2. The output end 231a-2 of the second selector circuit 231-2 is electrically connected to an output line 260-2. The output line 260-2 is electrically connected to the switching device 40.

[0083] The configurations of the first selection circuit 231-1 and the second selection circuit 231-2 are identical. Therefore, the operations of the first selection circuit 231-1 are described below. The first selection circuit 231-1 selects from (I.) the electrical power of the anode of the first diode 301-1 and (II.) the electrical power of the anode of the second diode 302-1 the electrical power that has the higher voltage. If the voltage applied to the first diode 301-1 via the first electrical power source line 240 is higher than the voltage applied to the second diode 302-1 via the second electrical power source line 250, then, in particular, a line from the first diode 301-1 to the output end 231a-1 in the first selection circuit 231-1 is energized. In this case, the first selection circuit 231-1 outputs the electrical power of the first capacitor section 201 from the output end 231a-1 to the output line 260-1.The electrical power of the first capacitor section 201 is supplied to the brake device 30 via the output line 260-1.

[0084] If, on the other hand, the voltage applied to the second diode 302-1 via the second power supply line 250 is higher than the voltage applied to the first diode 301-1 via the first power supply line 240, a line from the second diode 302-1 to the output terminal 231a-1 is energized. In this case, the first selector circuit 231-1 outputs the electrical power of the second capacitor section 211 from the output terminal 231a-1 to the output line 260-1. The electrical power of the second capacitor section 211 is supplied to the brake device 30 via the output line 260-1. <Zusammenfassung des Betriebs>

[0085] If the state of an ignition switch (not shown) changes from an OFF state to an ON state, the first electrical power control section 202 applies the predetermined constant first voltage V1 to the first electrical power source line 240. The electrical power of the first capacitor section 201 is supplied via the first electrical power source line 240 to the parking assist ECU 10, the drive unit 20, and the steering unit 50. Additionally, the electrical power of the first capacitor section 201 is supplied via the first electrical power source line 240 to the electrical power source redundancy circuit 230. The electrical power of the first capacitor section 201 is supplied via the electrical power source redundancy circuit 230 to the brake unit 30 and the switching change unit 40.Thus, the parking assist ECU 10, the drive unit 20, the brake unit 30, the shift change unit 40, and the steering unit 50 are activated by the electrical power of the first capacitor section 201. It should be noted that if the parking assist control is not activated, the electrical power of the second capacitor section 211 is not supplied to the electrical power source redundancy circuit 230.

[0086] The following describes the operation of the vehicle control unit if (1) the electrical power source device 200 is activated normally, and if (2) a malfunction occurs in the first electrical power source device 200. (1) Case that the first electrical power source device 200 is normally activated.

[0087] The parking assist ECU 10 sends a start instruction to the second electrical power control section 212 if (I.) the parking assist ECU 10 receives the assist request signal, and (II.) an execution condition described below is met. In response to the start instruction, the second electrical power control section 212 applies the predetermined constant second voltage V2 to the second electrical power source line 250. Subsequently, the parking assist ECU 10 determines the vehicle's direction of travel, steering pattern, and speed pattern as described above, and initiates the execution of the parking assist control in accordance with these determined directions of travel, steering patterns, and speed patterns.If the parking assist control is executed and the first electrical power source device 200 is activated normally, the electrical power supplied to it via the first electrical power source line 240 (i.e., the electrical power of the first capacitor section 201) activates the parking assist ECU 10, the drive unit 20, and the steering unit 50. Additionally, the voltage of the first electrical power source line 240 (i.e., the predetermined constant first voltage V1) is higher than the voltage of the second electrical power source line 250 (i.e., the predetermined constant second voltage V2).Thus, the first selection circuit 231-1 outputs the electrical power of the first capacitor section 201, which is supplied to the output line 260-1 via the first electrical power source line 240, and the second selection circuit 231-2 outputs the electrical power of the first capacitor section 201, which is supplied to the output line 260-2 via the first electrical power source line 240. Thus, the braking device 30 and the switching device 40 are activated by the electrical power of the first capacitor section 201. (2) Case that the malfunction occurs in the first electrical power source device 200.

[0088] If a malfunction occurs in the first electrical power source device 200 during the execution of the parking assist control, the electrical power of the first capacitor section 201 is not supplied to the first electrical power source line 240. This reduces the voltage of the first electrical power source line 240 (for example, to zero). The parking assist ECU 10, the drive unit 20, and the steering unit 50 cease their activation. In this case, the voltage of the second electrical power source line 250 (i.e., the predetermined constant second voltage V2) becomes higher than the voltage of the first electrical power source line 240 (i.e., zero).Thus, the first selector circuit 231-1 outputs the electrical power of the second capacitor section 211 to output line 260-1, and the second selector circuit 231-2 outputs the electrical power of the second capacitor section 211 to output line 260-2. Even if a malfunction occurs in the first electrical power source device 200, the electrical power of the second capacitor section 211 is supplied to the braking device 30 via the first selector circuit 231-1 and to the switching device 40 via the second selector circuit 231-2. Thus, the braking device 30 and the switching device 40 are activated by the electrical power of the second capacitor section 211.

[0089] While the parking support ECU 10 performs the parking support control, the parking support ECU 10 communicates via the CAN 90 with the machine ECU 21, the brake ECU 31, the SBW ECU 41 and the EPS ECU 51 every time a predetermined time Tm elapses. In particular, the parking assist ECU 10 sends the instruction signals described above, along with the control instructions, to the machine ECU 21, the brake ECU 31, the SBW ECU 41, and the EPS ECU 51, and receives response signals from the machine ECU 21, the brake ECU 31, the SBW ECU 41, and the EPS ECU 51. If a malfunction occurs in the first electrical power source device 200, the electrical power from the first capacitor section 201 is not supplied to the parking assist ECU 10, and the parking assist ECU 10 stops activating. This stops the transmission of the instruction signals.In this case too, according to the above description, the brake device 30 and the switching device 40 are activated by the electrical power of the second capacitor section 211.

[0090] If a malfunction occurs in the first electrical power source device 200, the vehicle control unit executes a stop control to bring the vehicle to a halt. The stop control comprises (I.) brake force control executed by the brake ECU 31 (hereinafter referred to as the "first control") and (II.) shift control executed by the shift change device 40 (hereinafter referred to as the "second control").

[0091] Specifically, the brake ECU 31 determines that a malfunction occurs in the first electrical power source device 200 if, during the execution of the parking assist control, the brake ECU 31 has not received the instruction signal from the parking assist ECU 10 for a predetermined time threshold Tth. It should be noted that the predetermined time threshold Tth is longer than the predetermined time Tm. If the brake ECU 31 determines that a malfunction occurs in the first electrical power source device 200, the brake ECU 31 executes the first control action. The first control action is a control action to stop the vehicle by applying braking force to the wheels before the vehicle reaches the target position Ptgt.

[0092] Similarly, the SBW-ECU 41 determines that a malfunction occurs in the first electrical power source device 200 if, during the execution of the parking assist control, the SBW-ECU 41 has not received the instruction signal from the parking assist ECU 10 for the predetermined time threshold Tth. If the SBW-ECU 41 determines that a malfunction occurs in the first electrical power source device 200, the SBW-ECU 41 executes the second control. The second control is a control to change the shift position of the transmission 24 to the park position. The state of the transmission 24 is changed to a park lock state by the second control. Thus, the vehicle can be stopped.

[0093] It should be noted that the SBW-ECU 41 begins executing the second control at the time a predetermined time Ta expires, because the SBW-ECU 41 determines that the malfunction is occurring in the first electrical power source device 200. In other words, the SBW-ECU 41 begins executing the second control after it has paused for the predetermined time Ta. While the SBW-ECU 41 is paused, the brake ECU 31 starts executing the first control. This reduces the vehicle speed Vs. Thus, the SBW-ECU 41 has an increased chance of executing the second control (i.e., changing the gear position to the park position) when the vehicle speed Vs is less than or equal to the predetermined speed threshold Vsth.

[0094] Even if a malfunction occurs in the first electrical power source device 200 during the execution of the parking assist control, the braking device 30 and the switching device 40 are activated by the electrical power of the second capacitor section 211, as described above. The braking device 30 performs the first control, and the switching device 40 performs the second control. Thus, even if a malfunction occurs in the first electrical power source device 200 during the execution of the parking assist control with the driver outside the vehicle, the vehicle can still be stopped.

[0095] While the parking assist ECU 10 is performing parking assist control, the vehicle may be moving down a slope. If the malfunction occurs in the first electrical power source device 200 while the vehicle is moving down the slope, the time until the vehicle stops may be increased, or the distance required to stop the vehicle may be increased, or the vehicle may continue moving without stopping.

[0096] To address this problem, the parking assist ECU 10 calculates an index value representing the degree of a gradient of a road along which the vehicle is traveling, assuming the first electrical power source device 200 is in a normal state while the parking assist ECU 10 is performing parking assist control. In this embodiment, the index value is a gradient angle θ, which is an angle defined between a road surface in front of the vehicle and a horizontal plane. The parking assist ECU 10 calculates the gradient angle θ using signals from the motion state sensors (the accelerometer 63 and the wheel speed sensors 64) using known techniques (see, for example, Publication JP 6-74320A).In this embodiment, the gradient angle θ takes on a positive value if the vehicle is moving along an upward slope, and a negative value if the vehicle is moving along a downward slope.

[0097] The parking assist ECU 10 then determines whether a predetermined speed limit condition is met. This predetermined speed limit condition is met if the vehicle is moving downhill, specifically if the gradient angle θ is less than or equal to a predetermined negative gradient angle threshold θth. If the parking assist ECU 10 determines that the predetermined speed limit condition is met, it limits the vehicle speed Vs to a predetermined speed limit Vs_lim or lower. Note that the predetermined speed limit Vs_lim is lower than the initial speed Vs1.Thus, the predetermined speed limit Vs_lim, the first speed Vs1 and the predetermined speed threshold Vsth have a relationship according to an expression 1 described below. Vs_lim <Vs1<Vsth

[0098] Even if the malfunction occurs in the first electrical power source device 200 while the vehicle is moving downhill, the vehicle will still be moving at a relatively low speed. Therefore, the vehicle control unit can easily stop the vehicle by executing the stop control. This eliminates the possibility of the vehicle taking longer to stop, the distance required to stop, or continuing to move without being stopped.

[0099] Even if the braking device 30 executes the first control, the vehicle cannot be stopped due to the steep gradient of the downhill slope. In this case, the vehicle speed Vs gradually increases due to the gradient of the downhill slope. In such a situation, the vehicle control unit can stop the vehicle. The vehicle moves at a speed (Vs_lim) that is lower than the predetermined speed threshold Vsth if a malfunction occurs in the first electrical power source device 200. Thus, the vehicle speed Vs will not easily exceed the predetermined speed threshold Vsth if the shift control device 40 begins to execute the second control. Therefore, the shift control device 40 can change the gear position of the transmission 24 to the park position by executing the second control.

[0100] In this embodiment, as shown in Expression 1, the first speed Vs1 is also lower than the predetermined speed threshold Vsth. As a result, the vehicle is moving at a speed significantly lower than the predetermined speed threshold Vsth at the time the malfunction occurs in the first electrical power source device 200. Therefore, the switching device 40 can safely stop the vehicle by executing the second control action.

[0101] The controls described above are referred to below. Fig. 4 and Fig. 5 described. In an example according to Fig. 4. The vehicle Va moves along a level road 400 while the parking assist control is executed. A top view according to Fig. Figure 4 shows a change in the final target speed Vtgt over time as the vehicle VA moves from the starting position Pst, where the parking assist control was initiated, to the target position Ptgt. If the vehicle VA is moving along the level road 400, the parking assist ECU 10 sets the target speed Vsa of the speed pattern as the final target speed Vtgt. Thus, the change in the final target speed Vtgt over time corresponds to Fig. 4 a change in the target velocity Vsa defined by the velocity pattern.

[0102] For example, according to Fig. 5 The vehicle VA moves along a road 500 which includes a downward slope 501. An upper view of Fig. Figure 5 shows the change in the final target speed Vtgt over time as the vehicle VA moves from the starting position Pst, where the parking assist control was initiated, to the target position Ptgt. At time t1, the vehicle VA begins to move down the slope 501. The gradient angle θ is less than or equal to the predetermined negative gradient angle threshold θth. Thus, the parking assist ECU 10 determines that a predetermined speed limit condition is met. In this case, the parking assist ECU 10 compares the target speed Vsa with the predetermined speed limit Vs_lim. The parking assist ECU 10 sets the final target speed Vtgt to a value less than the target speed Vsa defined by the speed pattern and the predetermined speed limit Vs_lim.At time t1, the predetermined speed limit Vs_lim is lower than the target speed Vsa (= Vs1), which is defined by the speed pattern. Therefore, the parking assistance ECU 10 sets the final target speed Vtgt to the predetermined speed limit Vs_lim. Thus, the parking assistance ECU 10 limits the final target speed Vtgt in such a way that the vehicle speed Vs is controlled to the predetermined speed limit Vs_lim.

[0103] At time t2, the vehicle is still moving along the downhill slope 501. Therefore, the predetermined speed limit condition is met. Consequently, the parking assistance ECU 10 compares the target speed Vsa, defined by the speed pattern, with the predetermined speed limit Vs_lim. At this time, the target speed Vsa, defined by the speed pattern, is lower than the predetermined speed limit Vs_lim. Therefore, the parking assistance ECU 10 sets the final target speed Vtgt to the target speed Vsa, defined by the speed pattern.

[0104] At time t3, the vehicle VA begins to move along a level road 502. At that time, the parking assistance ECU 10 determines that the predetermined speed limit condition is not met. Therefore, the parking assistance ECU 10 sets the final target speed Vtgt to the target speed Vsa defined by the speed pattern.

[0105] If the malfunction occurs in the first electrical power source device 200 while the vehicle VA is moving along the downward slope 501, the vehicle speed Vs corresponds to the predetermined speed limit Vs_lim. The predetermined speed limit Vs_lim is lower than the first speed Vs1. Thus, the braking device 30 can stop the vehicle VA for a short time by executing the first control action.

[0106] Even if the vehicle VA is not stopped due to the gradient of the downhill slope 501, despite the first control being executed, and the vehicle speed Vs gradually increases, the predetermined speed limit Vs_lim is set to a lower value than the predetermined speed threshold Vsth. Therefore, the vehicle speed Vs cannot exceed the predetermined speed limit Vsth if the shift control unit 40 begins to execute the second control, even if the vehicle speed Vs gradually increases. Thus, the shift control unit 40 can change the gear position of the transmission 24 to the park position by executing the second control. This allows the vehicle to be stopped safely. <betrieb>

[0107] The following describes the operation of the CPU of the parking assistance ECU 10 (hereinafter referred to as "CPU 1"). CPU 1 is configured or programmed to execute a flowchart in Fig. The 6 shown double parking support execution routine is to be executed every time a second time dT2 expires that is longer than or equal to the first time dT1.

[0108] It should be noted that CPU 1 executes an initial routine (not shown) to set the values ​​of the indicators described below to "0" if the ignition switch state changes from the OFF state to the ON state. If, as described above, the malfunction occurs in the first electrical power source device 200, the supply of electrical power to the parking assist ECU 10 is also stopped, and consequently, the activation of the parking assist ECU 10 is stopped. In this case, CPU 1 executes the initial routine to set the indicator values ​​to "0" if the supply of electrical power to the parking assist ECU 10 is restarted.

[0109] If, in addition, the state of the ignition switch is changed from the OFF state to the ON state, the first electrical power control section 202 of the first electrical power source device 200 applies the predetermined constant first voltage V1 to the first electrical power source line 240.

[0110] Additionally, CPU 1 is configured or programmed to execute a routine (not shown) to obtain vehicle environment information from the environmental sensors 60 at every time the first time dT1 expires. Additionally, CPU 1 is configured or programmed to execute a routine (not shown) to update the two-dimensional map based on the obtained vehicle environment information as described above.

[0111] At a predetermined time, CPU 1 begins processing a step of 600 according to Fig. 6 and proceeds to step 601 to determine if the value of a parking assist execution indicator X1 is "0". If the value of the parking assist execution indicator X1 is "0", then the parking assist execution indicator X1 represents that the parking assist control is not executed. Conversely, if the value of the parking assist execution indicator X1 is "1", then the parking assist execution indicator X1 represents that the parking assist control is executed.

[0112] If the value of the parking assistance execution indicator X1 is "0", CPU 1 determines "Yes" at step 601 and proceeds to step 602 to determine whether CPU 1 receives the assistance request signal from portable device 82 containing information about the assistance operating mode. If CPU 1 does not receive the assistance request signal, CPU 1 determines "No" at step 602 and proceeds directly to step 695 to complete the execution of this routine once.

[0113] If CPU 1 receives the support request signal, it determines "Yes" at step 602 and proceeds to step 603 to determine if a predetermined execution condition is met. The predetermined execution condition is met if all conditions A1 to A5, as described below, are satisfied.

[0114] Condition A1: CPU 1 receives the identification completion signal from collation ECU 71.

[0115] Condition A2: The support operating mode that represents the support request signal is the dual parking operating mode.

[0116] Condition A3: The position of the gearshift lever is the park position (P).

[0117] Condition A4: CPU 1 has detected that the permitted parking area has a size and shape that allows CPU 1 to double-park the vehicle.

[0118] Condition A5: CPU 1 does not receive a notification from the ECU of the second electrical power control section 212 indicating that a malfunction has occurred in the second capacitor section 211. In other words, the voltage of the capacitor in the second capacitor section 211 is not less than or equal to the predetermined voltage.

[0119] If the predetermined execution condition is not met, CPU 1 determines "No" at step 603 and proceeds directly to step 695 to complete the execution of this routine once. In this case, CPU 1 can send a display instruction to portable device 82. If portable device 82 receives the display instruction, it indicates to the parking application that the parking assistance control for double parking cannot be executed.

[0120] If, on the other hand, the predetermined execution condition is met, CPU 1 determines "Yes" at step 603 and executes the processing steps 604 to 610 as described below. Subsequently, CPU 1 proceeds to step 695 to complete the execution of this routine.

[0121] Step 604: CPU 1 sets the value of the parking assist execution flag X1 to "1".

[0122] Step 605: The CPU 1 sends the start instruction to the ECU of the second electrical power control section 212 of the second electrical power source device 210. If the ECU of the second electrical power control section 212 receives the start instruction, the ECU of the second electrical power control section 212 applies the predetermined constant second voltage V2 to the second electrical power source line 250.

[0123] Step 606: CPU 1 determines the target area to be an area that the vehicle's body would predictably occupy if the vehicle were parked in the detected permitted parking area. CPU 1 sets the target position Ptgt within the target area. Additionally, CPU 1 calculates the movement route along which it moves the vehicle from the starting position Pst (i.e., the current position) to the target position Ptgt.

[0124] Step 607: The CPU 1 determines the direction of movement of the vehicle (in particular the shift position of the transmission 24), the steering pattern of the vehicle and the speed pattern of the vehicle, which are used for a movement of the vehicle along the movement route.

[0125] Step 608: CPU 1 performs a target speed adjustment routine according to Fig. 7, which is described below. CPU 1 sets the final target speed Vtgt by executing the target speed setting routine according to Fig. 7 one.

[0126] Step 609: CPU 1 executes the parking assist control. Specifically, CPU 1 executes the shift control in accordance with the specified shift position by sending the shift control instruction to SWB-ECU 41. CPU 1 executes the steering angle control in accordance with the steering angle pattern by sending the steering instruction (target steering angle) to EPS-ECU 51. CPU 1 executes the drive force control in accordance with the final target speed Vtgt by sending the drive force control instruction to Machine ECU 21. Additionally, CPU 1 executes the brake force control in accordance with the final target speed Vtgt by sending the brake force control instruction to Brake ECU 31.

[0127] Step 610: CPU 1 sends the display instruction to portable device 82. If portable device 82 receives the display instruction, it indicates to the parking application that the parking assistance control is running. CPU 1 then proceeds directly to step 695 to complete the execution of this routine once.

[0128] If CPU 1 executes the routine according to Fig. If CPU 1 restarts and proceeds to step 601 after executing the parking assistance control, CPU 1 determines "No" at step 601 and proceeds to step 611. CPU 1 determines whether a predetermined termination condition has been met. The predetermined termination condition is met if the vehicle reaches the target position Ptgt.

[0129] If the predetermined termination condition is not met, CPU 1 determines "No" at step 611 and executes the processing steps 608 to 610 as described below. CPU 1 then proceeds to step 695 to complete the execution of this routine.

[0130] If, on the other hand, the predetermined termination condition is met, CPU 1 determines "Yes" at step 611 and executes the processing steps 612 and 613 as described below. Subsequently, CPU 1 proceeds to step 695 to complete the execution of this routine.

[0131] Step 612: CPU 1 sets the value of the parking assist execution flag X1 to "0".

[0132] Step 613: CPU 1 performs a predetermined termination process. Specifically, CPU 1 stops the vehicle at target position Ptgt by applying the brake force control. Subsequently, CPU 1 sends the shift control instruction to SBW-ECU 41 to change the gear position of transmission 24 to the park position while the vehicle remains stopped at target position Ptgt. Additionally, CPU 1 sends the display instruction to portable device 82. If portable device 82 receives the display instruction, it indicates to the parking application that the execution of the parking assist control is complete. Subsequently, CPU 1 changes the ignition switch state from the ON state to the OFF state.

[0133] If CPU 1 is processing step 608 of the in Fig. As the routine shown in step 6 progresses, CPU 1 starts processing step 700 of a routine according to Fig. 7, and proceeds to step 701 to calculate the gradient angle θ using the signals sent by the motion state sensors. Subsequently, CPU 1 proceeds to step 702 to determine whether the predetermined speed limit condition is met. As described above, CPU 1 determines that the predetermined speed limit condition is met if the gradient angle θ is less than or equal to the predetermined negative gradient angle threshold θth.

[0134] If the predetermined speed limit condition is met, CPU 1 determines "Yes" at step 702 and proceeds to step 703. If CPU 1 proceeds to step 703, it sets the final target speed Vtgt to a value smaller than the target speed Vsa defined by the speed pattern and the predetermined speed limit Vs_lim. Note that a min function at step 703 is a function of selecting a value smaller than the target speed Vsa and the predetermined speed limit Vs_lim. Subsequently, CPU 1 proceeds to step 795 and continues processing from step 608 according to the following steps. Fig. 6 to a step 609.

[0135] If, on the other hand, the predetermined speed limit condition is not met, CPU 1 determines "No" at step 702 and proceeds to step 704 to adjust the final target speed Vtgt to the target speed Vsa defined by the speed pattern. Subsequently, CPU 1 proceeds to step 795 and then from step 608 to step 609 according to the following steps. Fig. 6 continued.

[0136] Furthermore, the CPU of the brake ECU 31 (hereinafter referred to as "CPU 2") is configured or programmed to execute an initial control execution routine according to a flowchart in Fig. 8 to be executed each time a second time dT2 elapses.

[0137] Thus, at a predetermined time, CPU 2 begins processing step 800 and proceeds to step 801 to determine whether the parking assist control is executed. If the parking assist control is not executed at that time, CPU 2 determines "No" at step 801 and proceeds directly to step 895 to complete one execution of this routine.

[0138] If the parking assist control is executed on the other side, CPU 2 determines "Yes" at step 801 and proceeds to step 802 to determine whether a predetermined fault condition is met. The predetermined fault condition is met if CPU 2 has not received the instruction signal from the parking assist ECU 10 for the predetermined time threshold Tth or longer. If the predetermined fault condition is not met, CPU 2 determines "No" at step 802 and proceeds directly to step 895 to complete one execution of the routine.

[0139] If a malfunction occurs in the first capacitor section 201 of the first electrical power source device 200, and the voltage of the first electrical power source line 240 drops to zero, the activation of the parking assist ECU 10 is stopped. The predetermined constant second voltage V2 of the second electrical power source line 250 then becomes higher than the voltage of the first electrical power source line 240. Thus, the first selection circuit 231-1 outputs the electrical power of the second capacitor section 211 to the brake device 30 via the output line 260-1. Even if a malfunction occurs in the first electrical power source device 200, this can still activate the CPU 2.

[0140] Thus, the predetermined malfunction condition is met, and CPU 2 determines "Yes" at step 802 and proceeds to step 803 to execute the first control action. Specifically, CPU 2 applies the braking force to the wheels by controlling the activation of the brake actuators 32. Subsequently, CPU 2 proceeds to step 895 to complete the execution of this routine once.

[0141] Furthermore, the CPU of the SBW-ECU 41 (hereinafter referred to as "CPU 3") is configured or programmed to execute a second control execution routine according to a flowchart in Fig. to execute 9 each time the second time dT2 expires.

[0142] At a predetermined time, CPU 3 starts processing at step 900 and proceeds to step 901 to determine whether the parking assist control is executed. If the parking assist control is not executed at that time, CPU 3 determines "No" at step 901 and proceeds directly to step 995 to complete the execution of this routine.

[0143] If, on the other hand, the parking assist control is executed, CPU 3 determines "Yes" at step 901 and proceeds to step 902 to determine whether the predetermined malfunction condition, as described above, is met. If the predetermined malfunction condition is not met, CPU 3 determines "No" at step 902 and proceeds directly to step 995 to complete the execution of this routine.

[0144] If a malfunction occurs in the first capacitor section 201 of the first electrical power source device 200, the first selection circuit 231-1 outputs the electrical power of the second capacitor section 211 to the switching device 40 via the output line 260-2 as described above. The CPU 3 can also be activated if a malfunction occurs in the first electrical power source device 200.

[0145] If the predetermined malfunction condition is met, CPU 3 determines "Yes" at step 902 and executes the processing steps 903 and 904 as described below. The processing then proceeds to step 995 to complete the execution of this routine.

[0146] Step 903: CPU 3 remains idle for a predetermined time Ta. As described above, CPU 2 begins to execute the first control while CPU 3 remains idle for the predetermined time Ta.

[0147] Step 904: The CPU 3 executes the second control action. In particular, the CPU 3 changes the switching position to the park position by controlling the activation of the SBW actuator 43.

[0148] According to the configuration described above, the vehicle control unit determines whether the predetermined speed limit condition is met while the vehicle control unit is executing the parking assist control. Specifically, the predetermined speed limit condition is a condition that is met if the vehicle is moving along the downhill slope. In particular, the predetermined speed limit condition is met if the gradient angle θ is less than or equal to the predetermined negative gradient angle threshold θth. If the parking assist ECU 10 determines that the predetermined speed limit condition is met, the parking assist ECU 10 limits the vehicle speed Vs to the predetermined speed limit Vs_lim.If the malfunction in the first electrical power source device 200 occurs while the vehicle is moving downhill, the vehicle will be traveling at a relatively low speed (= Vs_lim) at the time the malfunction occurs. Therefore, the vehicle control unit can easily stop the vehicle by executing the stop control. This eliminates the possibility of the vehicle continuing to move without stopping, or of the time until the vehicle stops increasing, or of the vehicle continuing to move without being stopped.

[0149] Furthermore, the predetermined speed limit Vs_lim is lower than the predetermined speed threshold Vsth. Therefore, the vehicle speed Vs is less than or equal to the predetermined speed threshold Vsth at the time when the switching device 40 begins to execute the second control. Thus, the switching device 40 can stop the vehicle VA by executing the second control.

[0150] Furthermore, the brake ECU 31 begins executing the first control action at a time when it determines that a malfunction has occurred in the first electrical power source device 200. The SBW ECU 41 then begins executing the second control action at a time when the predetermined time Ta expires, due to the malfunction occurring in the first electrical power source device 200. Thus, the shift position is changed to the park position, and the vehicle is decelerated. In other words, the shift change device 40 can execute the second control action at a vehicle speed Vs that is lower than or equal to the predetermined speed threshold Vsth.

[0151] For example, if the malfunction occurs in the first electrical power source 200 while the vehicle is moving down a steep slope, the brake device 30 must continuously apply a relatively large braking force to the wheels to slow the vehicle. Therefore, electrical power should be continuously supplied to the brake device 30 from the second electrical power source 210. However, the electrical power source capacity of the second electrical power source 210 is smaller than that of the first electrical power source 200. Consequently, the electrical power required to slow the vehicle cannot be continuously supplied from the second electrical power source 210 to the brake device 30.If the electrical power required to decelerate the vehicle is not continuously supplied from the second electrical power source device 210 to the braking device 30, the vehicle speed Vs gradually increases due to the gradient of the downward slope. However, even if the vehicle speed Vs gradually increases, according to the configuration of the exemplary embodiment, the vehicle speed Vs will not easily exceed the predetermined speed threshold Vsth at the point in time when the switching device 40 begins to execute the second control. Therefore, even if the electrical power source capacity of the second electrical power source device 210 is relatively low, the vehicle control unit can still stop the vehicle using the second control. Thus, the low electrical power source capacity of the second electrical power source device 210 is acceptable.Thus, the configuration of a redundant electrical power source implementation can be achieved at low cost.

[0152] It should be noted that the invention is not limited to the aforementioned embodiments, and various modifications may be applied within the scope of the invention. <Abwandlungsbeispiel 1>

[0153] The processing operations described below can be performed between step 702 and step 703 of the routine according to Fig. 7. CPU 1 can be configured to set the predetermined velocity limit Vs_lim such that the predetermined velocity limit Vs_lim decreases with an increase in the gradient of the downward slope. CPU 1 can set the predetermined velocity limit Vs_lim by applying the gradient angle θ to a first map M1(θ) according to Fig. Apply equation 10 (Vs_lim ← M1(θ)). The first map M1 defines a relationship between the gradient angle θ and the predetermined velocity limit Vs_lim. If, in the first map M1, the gradient angle θ is less than or equal to the predetermined negative gradient angle threshold θth and greater than a first gradient angle θ1, the predetermined velocity limit Vs_lim is a second velocity Vs2. If the gradient angle θ is less than or equal to the first gradient angle θ1 and greater than a second gradient angle θ2, the predetermined velocity limit Vs_lim is a third velocity Vs3. If the gradient angle θ is less than or equal to the second gradient angle θ2, the predetermined velocity limit Vs_lim is a fourth velocity Vs4. In this respect, the velocities Vs1, Vs2, Vs3 and Vs4 exhibit a relationship of “Vs4 < Vs3 < Vs2 < Vs1”.According to the above description, CPU 1 can be configured to decrease the predetermined speed limit Vs_lim in a step-like manner depending on the degree of the gradient of the downward slope.

[0154] As the gradient of the downward slope increases, the likelihood of the vehicle stopping decreases. According to this configuration, as the gradient of the downward slope increases, the vehicle speed Vs decreases while the parking assist control is executed. Thus, the vehicle control unit can easily stop the vehicle by executing the stop control. Additionally, the switching device 40 has an increased probability of executing the second control with a vehicle speed Vs that is less than or equal to the predetermined speed threshold Vsth.

[0155] In another variation, CPU 1 can be configured to apply the predetermined speed threshold Vs_lim to a second card M2(θ) by applying the gradient angle θ according to Fig. 11. To apply (Vs_lim <- M2(θ)). The second chart M2 defines a relationship between the gradient angle θ and the predetermined velocity limit Vs_lim. If, in the second chart M2, the gradient angle θ is equal to the predetermined negative gradient angle threshold θth, the predetermined velocity limit Vs_lim is the second velocity Vs2, which is lower than the first velocity Vs1. In the second chart M2, the predetermined velocity limit Vs_lim gradually decreases with a decrease in the gradient angle θ (i.e., with an increase in the degree of the gradient of the downward slope). If the gradient angle θ is less than or equal to a second gradient angle θ2, the predetermined velocity limit Vs_lim is the fourth velocity Vs4.According to the above description, CPU 1 can be configured to gradually decrease the predetermined speed limit Vs_lim depending on the degree of the gradient of the downward slope. <Abwandlungsbeispiel 2>

[0156] The first selection circuit 231-1 can be omitted from the first electrical power source redundancy circuit 230. According to this configuration, the electrical power source line 240 is directly electrically connected to the brake device 30. If a malfunction occurs in the first electrical power source device 200, the brake device 30 is not activated. The electrical power of the second capacitor section 211 is supplied only to the switching device 40 by means of the second selection circuit 231-2. Thus, only the switching device 40 is activated by using the electrical power of the second capacitor section 211. The switching device 40 executes the second control without waiting for the predetermined time Ta if the predetermined malfunction condition is met. This stops the vehicle.

[0157] If, according to this modified example, the malfunction occurs in the first electrical power source device 200 while the vehicle is moving along the downward slope, the switching change device 40 can perform the second control, where the vehicle speed Vs is less than or equal to the predetermined speed threshold Vsth. <Abwandlungsbeispiel 3>

[0158] The second selection circuit 231-2 can be omitted from the electrical power source redundancy circuit 230. According to this configuration, the first electrical power source line 240 is directly electrically connected to the switching device 40. If a malfunction occurs in the first electrical power source device 200, the switching device 40 is not activated. The electrical power of the second capacitor section 211 is supplied only to the braking device 30 by means of the first selection circuit 231-1. Thus, using the electrical power of the second capacitor section 211 activates only the braking device 30. The braking device 30 performs the first control action if the predetermined malfunction condition is met. This stops the vehicle. <Abwandlungsbeispiel 4>

[0159] The speed pattern for the parking assist control is not limited to the speed patterns of the examples described above. The first speed Vs1 defined by the speed pattern can be greater than the predetermined speed threshold Vsth. In this configuration, the predetermined speed limit Vs_lim is lower than the predetermined speed threshold Vsth. Likewise, according to this configuration, the switching device 40 can execute the second control, where the vehicle speed Vs is less than or equal to the predetermined speed threshold Vsth, if the malfunction occurs in the first electrical power source device 200 while the vehicle is moving down the slope.

[0160] In another variation, the initial speed Vs1, defined by the speed pattern, is greater than the predetermined speed threshold Vsth. Furthermore, the predetermined speed limit Vs_lim can be lower than the initial speed Vs1 and equal to or greater than the predetermined speed threshold Vsth. Thus, the predetermined speed threshold Vsth, the predetermined speed limit Vs_lim, and the initial speed Vs1 have a relationship of "Vsth :::; Vs_lim < Vs1". In this case, the predetermined time Ta is set to a longer time than the time required to reduce the vehicle speed Vs to a lower speed than the predetermined speed threshold Vsth by the initial control (i.e., the braking force control).According to this configuration, the switching device 40 can execute the second control, where the vehicle speed Vs is less than or equal to the predetermined speed threshold Vsth. <Abwandlungsbeispiel 5>

[0161] The index value representing the gradient of the road is not limited to the index value described above. For example, the index value can be a gradient value Sv. The gradient value Sv is the ratio of the horizontal length of a distance traveled by the vehicle during a given time to the vertical length of a distance traveled by the vehicle during that same time. The gradient value Sv is expressed as a percentage. The gradient value Sv (%) takes a positive value if the vehicle is traveling uphill and a negative value if the vehicle is traveling downhill. The parking assist ECU 10 can calculate the gradient value Sv using established techniques.For example, the parking assistance ECU 10 can apply the gradient value Sv to a predetermined map by applying a difference between a base acceleration and the actual longitudinal acceleration Gx. For example, the base acceleration is an acceleration corresponding to the amount of accelerator pedal actuation, or accelerator opening degree, as the vehicle travels along a level road. The map defines the difference between the base acceleration and the actual longitudinal acceleration Gx such that the absolute value of the gradient value Sv increases with an increase in the absolute value of the difference between the base acceleration and the actual longitudinal acceleration Gx. With this configuration, CPU 1 determines the gradient value Sv at step 702 of the routine according to the following. Fig. 7, that the predetermined velocity limit condition is satisfied if the gradient value Sv is less than or equal to a predetermined negative gradient threshold Svth.

[0162] It should be noted that known inclinometers or gradient angle sensors can be used to obtain the index value described above. Furthermore, the parking assistance ECU 10 can be configured to determine, using road-facing cameras or laser beam devices, whether the vehicle is moving along the downhill slope (see, for example, publication JP 2013 - 205 196 A). <Abwandlungsbeispiel 6>

[0163] The brake ECU 31 and the SBW ECU 41 can be configured to determine whether the malfunction in the first electrical power source device 200 is related to communication between the first electrical power source device 200 and the first electrical power source device 200. According to this configuration, for example, the brake ECU 31 sends a predetermined signal to the first electrical power control section 202 of the first electrical power source device 200 each time a predetermined time elapses and receives a response signal in reply to the sent signal. If the brake ECU 31 does not receive the response signal from the first electrical power control section 202 for the predetermined time threshold Tth or more during the execution of the parking assist control, the brake ECU 31 can determine that the malfunction is occurring in the first electrical power source device 200.Using a similar technique, the SBW-ECU 41 can communicate with the first electrical power control section 202 and determine whether the malfunction occurs in the first electrical power source device 200. <Abwandlungsbeispiel 7>

[0164] In parallel parking mode and exit parking mode, similar controls are executed to the parking assistance control described above, with the exception that the target area to which the vehicle is moved differs. Thus, the routines according to the Fig. 6 to 9 are used for the parallel parking mode and the parking exit mode.

[0165] If the parking assistance control is executed in parallel parking mode, the predetermined execution condition of step 603 of the routine is applied according to Fig. 6 is replaced with a condition that is satisfied if all conditions B1 to B5 described below are satisfied.

[0166] Condition B1: CPU 1 receives the identification completion signal from collation ECU 71.

[0167] Condition B2: The support operating mode represented by the support request signal is the parallel parking operating mode.

[0168] Condition B3: The position of the gearshift lever is the park position (P).

[0169] Condition B4: The CPU 1 detects the permitted parking area with a size and shape that allows the vehicle to be parked parallel.

[0170] Condition B5: The CPU 1 does not receive a notification from the ECU of the second electrical power control section 212 informing it that the malfunction is occurring in the second capacitor section 211.

[0171] If the parking assistance control is executed in the exit mode, the predetermined execution condition of step 603 of the routine is met according to Fig. 6 is replaced by a condition that is satisfied if all conditions C1 to C5 described below are satisfied.

[0172] Condition C1: CPU 1 receives the identification completion signal from collation ECU 71.

[0173] Condition C2: The support operating mode represented by the support request signal is the parking mode.

[0174] Condition C3: The position of the gearshift lever is the park position (P).

[0175] Condition C4: The CPU 1 detects the permitted parking area with a size and shape that allows the vehicle to be parked out.

[0176] Condition C5: The CPU 1 does not receive a notification from the ECU of the second electrical power control section 212, which informs that the malfunction is occurring in the second capacitor section 211. <Abwandlungsbeispiel 8>

[0177] Circuits other than the diode-OR circuits can be used as the first selection circuit 231-1 and the second selection circuit 231-2. For example, the electrical power source redundancy circuit 230 can include a so-called relay circuit. The relay circuit includes a switch that changes from a first state, in which the first electrical power source line 240 is electrically connected to the output line 260-1 or the output line 260-2, to a second state, in which the second electrical power source line 250 is electrically connected to the output line 260-1 or the output line 260-2. According to this configuration, the electrical power source redundancy circuit 230 further includes an ECU that detects the malfunction of the first electrical power source device 200.In response to a detected malfunction of the first electrical power source device 200, the ECU changes the state of the switch from the first state to the second state. This ECU, which detects the malfunction of the first electrical power source device 200, can monitor whether the voltage of the second electrical power source line 250 is higher than the voltage of the first electrical power source line 240. Subsequently, this ECU can determine that a malfunction is occurring in the first electrical power source device 200 if the voltage of the second electrical power source line 250 is higher than the voltage of the first electrical power source line 240.

[0178] Furthermore, circuits using MOSFETs can be used as the first selection circuit 231-1 and the second selection circuit 231-2. With this configuration, the selection circuit 231 can selectively output one of the electrical power supplied to the first capacitor section 201 via the first electrical power source line 240 and the electrical power supplied to the second capacitor section 211 via the second electrical power source line 250. <Abwandlungsbeispiel 9>

[0179] The configuration described above can be used for valet parking (or a parking service). Valet parking is the control of autonomous vehicle movement within the parking lot to park the vehicle itself in an available space. A control unit that executes the valet parking function is located at the parking lot, not on the vehicle. The control unit monitors the parking lot's status (for example, the number of parked vehicles, the number of available spaces, and the positions of those spaces). After the driver exits the vehicle, the control unit sends a command signal to initiate valet parking. This allows the vehicle to move autonomously within the parking lot and park itself in the available space. <Abwandlungsbeispiel 10>

[0180] The configurations described above can be used for autonomous driving control systems. Autonomous driving control is a system that autonomously controls the vehicle's speed and the steering angle of the steered wheels without requiring any driving input from the driver. For this configuration, the vehicle is equipped with an autonomous driving control unit (ECU). For example, the autonomous driving ECU uses the autonomous driving control system to move the vehicle so that the vehicle speed (Vs) is controlled to a predetermined target speed (Vset). The target speed (Vset) can be set by the driver.The target speed Vset can be set depending on the vehicle's environmental situation (for example, the distance between a vehicle and a vehicle ahead, and the time required for the vehicle to reach the vehicle ahead). If the malfunction occurs in the first electrical power source device 200 while the autonomous driving control is running, the autonomous driving ECU determines whether the predetermined speed limit condition is met. If the autonomous driving ECU determines that the predetermined speed limit condition is met, it limits the vehicle speed Vs to the predetermined speed limit Vs_lim or less. The predetermined speed limit Vs_lim is lower than the target speed Vset.If the malfunction occurs in the first electrical power source device 200 while the autonomous driving control is running, at least one of the brake device 30 and the switching device 40 will perform the stop control of stopping the vehicle.

[0181] During parking assist control, a vehicle control unit sets a target speed for the vehicle such that a maximum value of the target speed is a first speed. The vehicle control unit performs the parking assist control by maintaining the vehicle's speed at a speed less than or equal to the predetermined speed limit, which is less than the first speed, if a predetermined condition is met that the vehicle is moving downhill, provided that a first electrical power source device (200) is in a normal state during parking assist control. At least one brake device (30) and one switching device (40) perform a stop control of stopping the vehicle if a malfunction occurs in the first electrical power source device during parking assist control.< / betrieb>

Claims

[1] Vehicle control unit, with: a drive device (20) which applies a driving force to at least one drive wheel of wheels of a vehicle; a braking device (30) that applies a braking force to the wheels; a shift-changing device (40) that changes a shift position of a transmission (24) of the vehicle to one of positions that include a forward movement position, a reverse movement position and a park position; a steering device (50) that controls a steering angle of at least one steered wheel of the wheels; a control unit (10) configured to receive an assistance request generated by a portable device (82), and a parking assistance control consisting of (I.) a determination of a movement route along which the control unit (10) moves the vehicle from a present position of the vehicle to a predetermined target position in response to receiving the assistance request, and (II.) a control of activations of the drive device (20), the brake device (30), the shift-change device (40) and the steering device (50) to move the vehicle along the determined movement route; a first electrical power source device (200) which is installed in the vehicle; a second electrical power source device (210) installed in the vehicle; and an electrical power supply circuit (220) which, during the execution of the parking assistance control by the control unit (10), supplies electrical power from the first electrical power source device (200) to the drive unit (20), the brake device (30), the switching device (40), the steering device (50) and the control unit (10), if the first electrical power source device (200) is in a normal state, and, during the execution of the parking assistance control by the control unit (10), supplies electrical power from the second electrical power source device (210) to at least one of the brake device (30) and the switching device (40), if a malfunction occurs in the first electrical power source device (200), wherein the control unit (10) is configured to set a target speed of the vehicle during the execution of the parking support control by the control unit (10) such that a maximum value of the target speed is a first speed, characterized by , that the control unit (10) is configured to perform the parking assistance control by maintaining the vehicle's speed at a speed slower than or equal to a predetermined speed limit slower than the first speed during the execution of the parking assistance control by the control unit (10), if the control unit (10) determines that a predetermined condition, namely that the vehicle is moving along a downhill slope, is met based on an index value representing a degree of gradient of a road along which the vehicle is moving, if the first electrical power source device (200) is in the normal state, at least one of the brake device (30) and the switching device (40) is equipped to perform a stop control of a stopping of the vehicle during the execution of the parking support control by the control unit (10) if the malfunction occurs in the first electrical power source device (200), the switching device (40) is configured to be able to change the switching position to the park position if the speed of the vehicle is slower than or equal to a predetermined speed threshold; the predetermined speed limit is lower than the predetermined speed threshold; and the switching change device (40) is configured to perform a switching control of changing the switching position to the park position as the stop control if the malfunction occurs in the first electrical power source device (200) while the control unit (10) is performing the parking support control. [2] Vehicle control unit according to claim 1, wherein the first speed is slower than the predetermined speed threshold. [3] Vehicle control unit according to claim 1, wherein the control unit (10) is configured to adjust the predetermined speed limit such that the predetermined speed limit decreases with an increase in the degree of the gradient of the downward slope if the predetermined condition is met. [4] Vehicle control unit according to claim 1, wherein: the switching device (40) is configured to begin an execution of the switching control after the brake device (30) begins to execute the brake force control. [5] Vehicle control unit according to claim 1, wherein: the first electrical power source device (200) has a first electrical capacitance; and the second electrical power source device (210) has a second electrical capacitance that is smaller than the first electrical capacitance. [6] Vehicle control unit, with: a drive device (20) which applies a driving force to at least one drive wheel of wheels of a vehicle; a braking device (30) that applies a braking force to the wheels; a shift-changing device (40) that changes a shift position of a transmission (24) of the vehicle to one of positions that include a forward movement position, a reverse movement position and a park position; a steering device (50) that controls a steering angle of at least one steered wheel of the wheels; a control unit (10) which is configured to perform control for autonomous driving of autonomous control of activations of the drive unit (20), the brake unit (30), the shift change unit (40) and the steering unit (50); a first electrical power source device (200) which is installed in the vehicle; a second electrical power source device (210) which is installed in the vehicle, and an electrical power supply circuit (220) which, during the execution of the parking assistance control by the control unit (10), supplies electrical power from the first electrical power source device (200) to the drive unit (20), the brake device (30), the switching device (40), the steering device (50) and the control unit (10), if the first electrical power source device (200) is in a normal state, and during the execution of a parking assistance control by the control unit (10), supplies electrical power from the second electrical power source device (210) to at least one of the brake device (30) and the switching device (40), if a malfunction occurs in the first electrical power source device (200), wherein the control unit (10) is configured to move the vehicle to a predetermined target speed by controlling the vehicle's speed, while the control unit (10) performs the parking assistance control, characterized by , that the control unit (10) is configured to execute the parking assistance control by maintaining the vehicle's speed at a speed slower than or equal to a predetermined speed limit slower than the predetermined target speed during the execution of the parking assistance control by the control unit (10), if the control unit (10) determines that a predetermined condition, namely that the vehicle is moving along a downhill slope, is met based on an index value representing a degree of gradient of a road along which the vehicle is moving, if the first electrical power source device (200) is in the normal state; and at least one of the brake device (30) and the switching device (40) is equipped to perform a stop control of a stopping of the vehicle during the execution of the autonomous driving control by the control unit (10) if the malfunction occurs in the first electrical power source device (200); the switching device (40) is configured to be able to change the switching position to the park position if the speed of the vehicle is slower than or equal to a predetermined speed threshold; the predetermined speed limit is lower than the predetermined speed threshold; and the switching change device (40) is configured to perform a switching control of changing the switching position to the park position as the stop control if the malfunction occurs in the first electrical power source device (200) while the control unit (10) is performing the parking support control.

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