Vehicle control system and control method of vehicle

This application claims priority to and the benefit of Japanese Patent Application No. 2018-169910 filed on Sep. 11, 2018, the entire disclosure of which is incorporated herein by reference.

The present invention relates to a vehicle control system and a control method of a vehicle.

Concerning driving support control of a vehicle, a detection means (a sensor, a camera, or the like) is provided in the vehicle to acquire information on the periphery. An example of the information on the periphery is the position of a white line on a road. For example, Japanese Patent Laid-Open No. 2017-013560 describes detecting a white line by a camera, performing abnormality determination based on variations in the detected white line, and inhibiting control of steering in a case of an abnormality.

One vehicle is sometimes provided with a plurality of detection means. For example, cameras are installed on the left and right sides in the front portion of a vehicle to expand the detection region or make the detection function redundant. In this case, since the installation positions of the cameras in the vehicle are different, a shift occurs in the detection result. For this reason, if control is performed using the detection result of one camera, and switching to the other camera occurs meanwhile, control according to a variation at the time of switching is needed.

The present invention stabilizes the behavior of a vehicle at the time of switching of a camera.

According to one aspect of the present invention, there is provided a vehicle control system provided with a first detection unit and a second detection unit, which are configured to acquire peripheral information of a self-vehicle, comprising: a control unit configured to perform traveling control of the self-vehicle using the peripheral information, wherein when switching from a first traveling state using peripheral information detected by the first detection unit to a second traveling state using peripheral information detected by the second detection unit is performed, the control unit suppresses a control amount based on the peripheral information of the self-vehicle.

According to another aspect of the present invention, there is provided a control method of a vehicle provided with a first detection unit and a second detection unit, which are configured to acquire peripheral information of a self-vehicle, comprising: performing traveling control by suppressing a control amount based on the peripheral information of the self-vehicle when switching from a first traveling state using peripheral information detected by the first detection unit to a second traveling state using peripheral information detected by the second detection unit is performed.

According to the present invention, it is possible to stabilize the behavior of a vehicle at the time of switching of a camera.

Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings).

FIG. 1 is a block diagram of a vehicle control system according to an embodiment;

FIG. 2 is a block diagram of the vehicle control system according to the embodiment;

FIG. 3 is a block diagram of the vehicle control system according to the embodiment;

FIG. 4 is a view for explaining switching of a camera according to the embodiment;

FIG. 5 is a view for explaining switching of a camera according to the embodiment;

FIG. 6 is a flowchart of processing at the time of switching of a camera according to the embodiment; and

FIG. 7 is a view for explaining an example of a steering control amount limitation method according to the embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. It should be noted that the following embodiments are not intended to limit the scope of the appended claims, and that not all the combinations of features described in the embodiments are necessarily essential to the solving means of the present invention. Two or more of a plurality of features described in the embodiments may arbitrarily be combined. In addition, the same reference numerals denote the same or similar parts, and a repetitive description thereof will be omitted.

First Embodiment

FIGS. 1 to 3 are block diagrams of a vehicle control system 1 according to an embodiment of the present invention. The vehicle control system 1 controls a vehicle V. In each of FIGS. 1 and 2 , an outline of the vehicle V is shown in a plan view and a side view. As an example, the vehicle V is a sedan-type four-wheeled vehicle. The vehicle control system 1 includes a control apparatus 1 A and a control apparatus 1 B. FIG. 1 is a block diagram showing the control apparatus 1 A, and FIG. 2 is a block diagram showing the control apparatus 1 B. FIG. 3 mainly shows the arrangement of communication lines between the control apparatus 1 A and the control apparatus 1 B and power supplies.

The control apparatus 1 A and the control apparatus 1 B make some functions implemented by the vehicle V multiplexed or redundant. This can improve the reliability of the system. The control apparatus 1 A performs, for example, not only automated driving control and normal operation control in manual driving but also traveling support control concerning risk avoidance and the like. The control apparatus 1 B mainly performs traveling support control concerning risk avoidance and the like. Traveling support will sometimes be referred to as driving support. The control apparatus 1 A and the control apparatus 1 B are caused to perform different control processes while making the functions redundant, thereby improving the reliability while distributing the control processes.

The vehicle V according to this embodiment is a parallel hybrid vehicle. FIG. 2 schematically shows the arrangement of a power plant 50 that outputs a driving force to rotate the driving wheels of the vehicle V. The power plant 50 includes an internal combustion engine EG, a motor M, and an automatic transmission TM. The motor M is usable as a driving source to accelerate the vehicle V and is also usable as a power generator upon deceleration or the like (regenerative braking).

<Control Apparatus 1 A>

The arrangement of the control apparatus 1 A will be described with reference to FIG. 1 . The control apparatus 1 A includes an ECU group (control unit group) 2 A. The ECU group 2 A includes a plurality of ECUs 20 A to 29 A. Each ECU includes a processor represented by a CPU, a storage device such as a semiconductor memory, an interface with an external device, and the like. The storage device stores programs to be executed by the processor, data to be used by the processor for processing, and the like. Each ECU may include a plurality of processors, storage devices, and interfaces. Note that the number of ECUs and the provided functions can appropriately be designed, and they can be subdivided or integrated as compared to this embodiment. Note that in FIGS. 1 and 3 , the names of the representative functions of the ECUs 20 A to 29 A are given. For example, the ECU 20 A is denoted by “automated driving ECU”.

The ECU 20 A executes control associated with automated driving as traveling control of the vehicle V. In automated driving, at least one of driving (acceleration of the vehicle V by the power plant 50 , and the like), steering, and braking of the vehicle V is automatically performed independently of the driving operation of the driver. In this embodiment, driving, steering, and braking are automatically performed.

The ECU 21 A is an environment recognition unit configured to recognize the traveling environment of the vehicle V based on the detection results of detection units 31 A and 32 A that detect the peripheral situation of the vehicle V. The ECU 21 A generates target data (to be described later) as peripheral environment information.

In this embodiment, the detection unit 31 A is an image capturing device (to be sometimes referred to as the camera 31 A hereinafter) configured to detect an object around the vehicle V by image capturing. The camera 31 A is attached to the windshield inside the vehicle cabin at the roof front of the vehicle V to capture the front side of the vehicle V. When images captured by the camera 31 A are analyzed, the contour of a target or a division line (a white line or the like) of a lane on a road can be extracted.

In this embodiment, the detection unit 32 A is a light detection and ranging (LIDAR) (to be sometimes referred to as the lidar 32 A hereinafter) configured to detect an object around the vehicle V by light, and detects a target around the vehicle V or measures the distance to a target. In this embodiment, five lidars 32 A are provided; one at each corner of the front portion of the vehicle V, one at the center of the rear portion, and one on each side of the rear portion. The number of lidars 32 A and their arrangement can appropriately be selected.

The ECU 29 A is a traveling support unit configured to execute control associated with traveling support (in other words, driving support) as traveling control of the vehicle V based on the detection result of the detection unit 31 A.

The ECU 22 A is a steering control unit configured to control an electric power steering device 41 A. The electric power steering device 41 A includes a mechanism that steers the front wheels in accordance with the driving operation (steering operation) of the driver on a steering wheel ST. The electric power steering device 41 A includes a motor that generates a driving force to assist the steering operation or automatically steer the front wheels, a sensor that detects the rotation amount of the motor, a torque sensor that detects the steering torque on the driver, and the like.

The ECU 23 A is a braking control unit configured to control a hydraulic device 42 A. A braking operation of the driver on a brake pedal BP is converted into a fluid pressure by a brake master cylinder BM and transmitted to the hydraulic device 42 A. The hydraulic device 42 A is an actuator capable of controlling, based on the fluid pressure transmitted from the brake master cylinder BM, the fluid pressure of hydraulic oil to be supplied to a brake device (for example, a disc brake device) 51 provided in each of the four wheels. The ECU 23 A performs driving control of a solenoid valve and the like provided in the hydraulic device 42 A. In this embodiment, the ECU 23 A and the hydraulic device 42 A form an electric servo brake. The ECU 23 A controls, for example, the distribution of a braking force by the four brake devices 51 and a braking force by regenerative braking of the motor M.

The ECU 24 A is a stop maintaining control unit configured to control an electric parking lock device 50 a provided in the automatic transmission TM. The electric parking lock device 50 a includes a mechanism that mainly locks the internal mechanism of the automatic transmission TM when the P range (parking range) is selected. The ECU 24 A can control lock and unlock by the electric parking lock device 50 a.

The ECU 25 A is an in-vehicle notification control unit configured to control an information output device 43 A that notifies information in the vehicle. The information output device 43 A includes, for example, a display device such as a head-up display and a voice output device. The information output device 43 A may further include a vibration device. The ECU 25 A causes the information output device 43 A to output, for example, various kinds of information such as a vehicle speed and an atmospheric temperature and information such as a path guidance.

The ECU 26 A is an external notification control unit configured to control an information output device 44 A that notifies information outside the vehicle. In this embodiment, the information output device 44 A is a direction indicator (hazard lamp). The ECU 26 A controls blinking of the information output device 44 A serving as a direction indicator, thereby notifying the exterior of the vehicle of the advancing direction of the vehicle V. In addition, the ECU 26 A controls blinking of the information output device 44 A serving as a hazard lamp, thereby increasing the attention of the exterior to the vehicle V.

The ECU 27 A is a driving control unit configured to control the power plant 50 . In this embodiment, one ECU 27 A is assigned to the power plant 50 . However, one ECU may be assigned to each of the internal combustion engine EG, the motor M, and the automatic transmission TM. The ECU 27 A controls the output of the internal combustion engine EG or the motor M or switches the gear range of the automatic transmission TM in correspondence with, for example, the driving operation of the driver detected by an operation detection sensor 34 a provided on an accelerator pedal AP or an operation detection sensor 34 b provided on the brake pedal BP, the vehicle speed, or the like. Note that as a sensor that detects the traveling state of the vehicle V, a rotation speed sensor 39 that detects the rotation speed of the output shaft of the automatic transmission TM is provided in the automatic transmission TM. The vehicle speed of the vehicle V can be calculated from the detection result of the rotation speed sensor 39 .

The ECU 28 A is a position recognition unit configured to recognize the current position or the route of the vehicle V. The ECU 28 A performs control of a gyro sensor 33 A, a GPS sensor 28 b , and a communication device 28 c and information processing of a detection result or a communication result. The gyro sensor 33 A detects the rotary motion of the vehicle V. The route of the vehicle V can be determined based on the detection result of the gyro sensor 33 A, and the like. The GPS sensor 28 b detects the current position of the vehicle V. The communication device 28 c performs wireless communication with a server configured to provide map information and traffic information, and acquires these pieces of information. A database 28 a can store accurate map information. The ECU 28 A can more accurately specify the position of the vehicle V on a lane based on the map information and the like.

An input device 45 A is arranged in the vehicle such that the driver can operate it, and accepts input of an instruction or information from the driver.

<Control Apparatus 1 B>

The arrangement of the control apparatus 1 B will be described with reference to FIG. 2 . The control apparatus 1 B includes an ECU group (control unit group) 2 B. The ECU group 2 B includes a plurality of ECUs 21 B to 25 B. Each ECU includes a processor represented by a CPU, a storage device such as a semiconductor memory, an interface with an external device, and the like. The storage device stores programs to be executed by the processor, data to be used by the processor for processing, and the like. Each ECU may include a plurality of processors, storage devices, and interfaces. Note that the number of ECUs and the provided functions can appropriately be designed, and they can be subdivided or integrated as compared to this embodiment. Note that in FIGS. 2 and 3 , the names of the representative functions of the ECUs 21 B to 25 B are given, like the ECU group 2 A.

The ECU 21 B is an environment recognition unit configured to recognize the traveling environment of the vehicle V based on the detection results of detection units 31 B and 32 B that detect the peripheral situation of the vehicle V, and also serves as a traveling support unit configured to execute control associated with traveling support (in other words, driving support) as traveling control of the vehicle V. The ECU 21 B generates target data (to be described later) as peripheral environment information.

Note that in this embodiment, the ECU 21 B has the environment recognition function and the traveling support function. However, an ECU may be provided for each function, like the ECU 21 A and the ECU 29 A of the control apparatus 1 A. Reversely, in the control apparatus 1 A, the functions of the ECU 21 A and the ECU 29 A may be implemented be one ECU, like the ECU 21 B.

In this embodiment, the detection unit 31 B is an image capturing device (to be sometimes referred to as the camera 31 B hereinafter) configured to detect an object around the vehicle V by image capturing. The camera 31 B is attached to the windshield inside the vehicle cabin at the roof front of the vehicle V to capture the front side of the vehicle V. When images captured by the camera 31 B are analyzed, the contour of a target or a division line (a white line or the like) of a lane on a road can be extracted. In this embodiment, the detection unit 32 B is a millimeter wave radar (to be sometimes referred to as the radar 32 B hereinafter) configured to detect an object around the vehicle V by a radio wave, and detects a target around the vehicle V or measures the distance to a target. In this embodiment, five radars 32 B are provided; one at the center of the front portion of the vehicle V, one at each corner of the front portion, and one at each corner of the rear portion. The number of radars 32 B and their arrangement can appropriately be selected.

The ECU 22 B is a steering control unit configured to control the electric power steering device 41 B. The electric power steering device 41 B includes a mechanism that steers the front wheels in accordance with the driving operation (steering operation) of the driver on the steering wheel ST. The electric power steering device 41 B includes a motor that generates a driving force to assist the steering operation or automatically steer the front wheels, a sensor that detects the rotation amount of the motor, a torque sensor that detects the steering torque on the driver, and the like. In addition, a steering angle sensor 37 is electrically connected to the ECU 22 B via a communication line L 2 to be described later, and the electric power steering device 41 B can be controlled based on the detection result of the steering angle sensor 37 . The ECU 22 B can acquire the detection result of a sensor 36 that detects whether the driver is gripping the steering handle ST, and can monitor the gripping state of the driver.

The ECU 23 B is a braking control unit configured to control a hydraulic device 42 B. A braking operation of the driver on the brake pedal BP is converted into a fluid pressure by the brake master cylinder BM and transmitted to the hydraulic device 42 B. The hydraulic device 42 B is an actuator capable of controlling, based on the fluid pressure transmitted from the brake master cylinder BM, the fluid pressure of hydraulic oil to be supplied to the brake device 51 of each wheel. The ECU 23 B performs driving control of a solenoid valve and the like provided in the hydraulic device 42 B.

In this embodiment, a wheel speed sensor 38 provided in each of the four wheels, a yaw rate sensor 33 B, and a pressure sensor 35 configured to detect the pressure in the brake master cylinder BM are electrically connected to the ECU 23 B and the hydraulic device 42 B, and based on the detection results of these, an ABS function, traction control, and the posture control function for the vehicle V are implemented. For example, the ECU 23 B adjusts the braking force of each wheel based on the detection result of the wheel speed sensor 38 provided in each of the four wheels, thereby suppressing skid of each wheel. In addition, the ECU 23 B adjusts the braking force of each wheel based on the rotation angular speed about the vertical axis of the vehicle V detected by the yaw rate sensor 33 B, thereby suppressing an abrupt posture change of the vehicle V.

The ECU 23 B also functions as an external notification control unit configured to control an information output device 43 B that notifies information outside the vehicle. In this embodiment, the information output device 43 B is a brake lamp, and the ECU 23 B can light the brake lamp at the time of braking or the like. This can increase the attention of a following vehicle to the vehicle V.

The ECU 24 B is a stop maintaining control unit configured to control an electric parking brake device (for example, a drum brake) 52 provided in each rear wheel. The electric parking brake device 52 includes a mechanism that locks the rear wheel. The ECU 24 B can control lock and unlock of the rear wheels by the electric parking brake devices 52 .

The ECU 25 B is an in-vehicle notification control unit configured to control an information output device 44 B that notifies information in the vehicle. In this embodiment, the information output device 44 B includes a display device arranged on the instrument panel. The ECU 25 B can cause the information output device 44 B to output various kinds of information such as a vehicle speed and fuel consumption.

An input device 45 B is arranged in the vehicle such that the driver can operate it, and accepts input of an instruction or information from the driver.

<Communication Lines>

An example of communication lines of the control system 1 , which communicably connect the ECUs, will be described with reference to FIG. 3 . The control system 1 includes communication lines L 1 to L 7 of wired communication. The ECUs 20 A to 27 A and 29 A of the control apparatus 1 A are connected to the communication line L 1 . Note that the ECU 28 A may also be connected to the communication line L 1 .

The ECUs 21 B to 25 B of the control apparatus 1 B are connected to the communication line L 2 . The ECU 20 A of the control apparatus 1 A is also connected to the communication line L 2 . The communication line L 3 connects the ECU 20 A and the ECU 21 B, and the communication line L 4 connects the ECU 20 A and the ECU 21 A. The communication line L 5 connects the ECU 20 A, the ECU 21 A, and the ECU 28 A. The communication line L 6 connects the ECU 29 A and the ECU 21 A. The communication line L 7 connects the ECU 29 A and the ECU 20 A.

The protocols of the communication lines L 1 to L 7 may be identical or different, and may be changed in accordance with the communication environment such as a communication speed, a communication amount, and durability. For example, the communication lines L 3 and L 4 may be Ethernet® from the viewpoint of communication speed. For example, the communication lines L 1 , L 2 , and L 5 to L 7 may be CAN.

The control apparatus 1 A includes a gateway GW. The gateway GW relays the communication line L 1 and the communication line L 2 . For this reason, for example, the ECU 21 B can output a control instruction to the ECU 27 A via the communication line L 2 , the gateway GW, and the communication line L 1 .

<Power Supply>

The power supply of the control system 1 will be described with reference to FIG. 3 . The control system 1 includes a large capacity battery 6 , a power supply 7 A, and a power supply 7 B. The large capacity battery 6 is a battery used to drive the motor M and charged by the motor M.

The power supply 7 A is a power supply that supplies power to the control apparatus 1 A, and includes a power supply circuit 71 A and a battery 72 A. The power supply circuit 71 A is a circuit that supplies the power of the large capacity battery 6 to the control apparatus 1 A, and, for example, lowers the output voltage (for example, 190 V) of the large capacity battery 6 to a reference voltage (for example, 12 V). The battery 72 A is a lead battery of, for example, 12 V. Since the battery 72 A is provided, the power can be supplied to the control apparatus 1 A even in a case in which the power supply of the large capacity battery 6 or the power supply circuit 71 A is shut down or lowers.

The power supply 7 B is a power supply that supplies power to the control apparatus 1 B, and includes a power supply circuit 71 B and a battery 72 B. The power supply circuit 71 B is a circuit that is similar to the power supply circuit 71 A and supplies the power of the large capacity battery 6 to the control apparatus 1 B. The battery 72 B is a battery similar to the battery 72 A, and is a lead battery of, for example, 12 V. Since the battery 72 B is provided, the power can be supplied to the control apparatus 1 B even in a case in which the power supply of the large capacity battery 6 or the power supply circuit 71 B is shut down or lowers.

<Redundancy>

Functions common to the control apparatus 1 A and the control apparatus 1 B will be described. When the same functions are made redundant, the reliability of the control system 1 can be improved. In addition, some redundant functions provide different functions, instead of multiplexing the same functions. This suppresses an increase in cost caused by the redundancy of functions.

[Actuator System]

Steering

The control apparatus 1 A includes the electric power steering device 41 A and the ECU 22 A that controls this. The control apparatus 1 B also includes the electric power steering device 41 B and the ECU 22 B that controls this.

Braking

The control apparatus 1 A includes the hydraulic device 42 A and the ECU 23 A that controls this. The control apparatus 1 B includes the hydraulic device 42 B and the ECU 23 B that controls this. All of these can be used for braking of the vehicle V. On the other hand, the main function of the braking mechanism of the control apparatus 1 A is the distribution of the braking force by the brake device 51 and the braking force by the regenerative braking of the motor M. On the other hand, the main function of the braking mechanism of the control apparatus 1 B is posture control and the like. Although the functions are common concerning braking, functions different from each other are provided.

Stop Maintaining

The control apparatus 1 A includes the electric parking lock device 50 a and the ECU 24 A that controls this. The control apparatus 1 B includes the electric parking brake device 52 and the ECU 24 B that controls this. All of these can be used to maintain the stop of the vehicle V. On the other hand, although the electric parking lock device 50 a is a device that functions when the P range of the automatic transmission TM is selected, the electric parking brake device 52 is a device that locks a rear wheel. Although the functions are common concerning stop maintaining of the vehicle V, functions different from each other are provided.

In-Vehicle Notification

The control apparatus 1 A includes the information output device 43 A and the ECU 25 A that controls this. The control apparatus 1 B includes the information output device 44 B and the ECU 25 B that controls this. All of these can be used to notify the driver of information. On the other hand, the information output device 43 A is, for example, a head-up display, and the information output device 44 B is a display device such as a measuring instrument. Although the functions are common concerning in-vehicle notification, display devices different from each other can be employed.

External Notification

The control apparatus 1 A includes the information output device 44 A and the ECU 26 A that controls this. The control apparatus 1 B includes the information output device 43 B and the ECU 23 B that controls this. All of these can be used to notify information outside the vehicle. On the other hand, the information output device 44 A is a direction indicator (hazard lamp), and the information output device 43 B is a brake lamp. Although the functions are common concerning external notification, functions different from each other are provided.

Different Points

The control apparatus 1 A includes the ECU 27 A that controls the power plant 50 . However, the control apparatus 1 B does not include a unique ECU that controls the power plant 50 . In this embodiment, both the control apparatuses 1 A and 1 B can solely perform steering, braking, and stop maintaining. Hence, even if the control apparatus 1 A or control apparatus 1 B suffers performance degradation, power supply shutdown, or communication interruption, it is possible to decelerate and maintain the stop state while suppressing lane departure. Additionally, as described above, the ECU 21 B can output a control instruction to the ECU 27 A via the communication line L 2 , the gateway GW, and the communication line L 1 , and the ECU 21 B can also control the power plant 50 . Since the control apparatus 1 B does not include a unique ECU that controls the power plant 50 , an increase in cost can be suppressed. However, the control apparatus 1 B may include a unique ECU.

[Sensor System]

Detection of Peripheral Situation

The control apparatus 1 A includes the detection units 31 A and 32 A. The control apparatus 1 B includes the detection units 31 B and 32 B. All of these can be used to recognize the traveling environment of the vehicle V. On the other hand, the detection unit 32 A is a lidar, and the detection unit 32 B is a radar. The lidar is generally advantageous in detecting a shape. Additionally, the radar is generally more advantageous than the lidar from the viewpoint of cost. When these sensors of different characteristics are used, it is possible to improve target recognition performance and reduce the cost. Both the detection units 31 A and 31 B are cameras. Cameras of different characteristics may be used. For example, one of them may be a camera of a resolution higher than the other. In addition, the angles of view may be different from each other.

As for comparison of the control apparatus 1 A and the control apparatus 1 B, the detection characteristics of the detection units 31 A and 32 A may be different from those of the detection units 31 B and 32 B. In this embodiment, the detection unit 32 A is a lidar whose target edge detection performance is higher than that of the radar (detection unit 32 B) in general. Additionally, the radar is generally excellent in the relative speed detection accuracy or weatherability as compared to the lidar.

In addition, if the camera 31 A has a resolution higher than that of the camera 31 B, the detection performance of the detection units 31 A and 32 A is higher than that of the detection units 31 B and 32 B. When the plurality of sensors of different detection characteristics and costs are combined, cost advantage can sometimes be obtained in the whole system. In addition, when the sensors of different detection characteristics are combined, detection omission or detection errors can be reduced as compared to a case in which redundancy is attained by identical sensors.

Vehicle Speed

The control apparatus 1 A includes the rotation speed sensor 39 . The control apparatus 1 B includes the wheel speed sensor 38 . Both can be used to detect the vehicle speed. On the other hand, the rotation speed sensor 39 detects the rotation speed of the output shaft of the automatic transmission TM, and the wheel speed sensor 38 detects the rotation speed of the wheels. Although the sensors are common concerning the capability of detecting the vehicle speed, the detection targets are different from each other.

Yaw Rate

The control apparatus 1 A includes the gyro sensor 33 A. The control apparatus 1 B includes the yaw rate sensor 33 B. Both can be used to detect the angular velocity about the vertical axis of the vehicle V. On the other hand, the gyro sensor 33 A is used to determine the route of the vehicle V, and the yaw rate sensor 33 B is used for posture control of the vehicle V, and the like. Although the sensors are common concerning the capability of detecting the angular velocity of the vehicle V, the use purposes are different from each other.

Steering Angle and Steering Torque

The control apparatus 1 A includes a sensor that detects the rotation amount of the motor of the electric power steering device 41 A. The control apparatus 1 B includes the steering angle sensor 37 . Both can be used to detect the steering angle of the front wheels. In the control apparatus 1 A, an increase in cost can be suppressed by using the sensor that detects the rotation amount of the motor of the electric power steering device 41 A, instead of additionally providing the steering angle sensor 37 . However, the steering angle sensor 37 may additionally be provided in the control apparatus 1 A.

In addition, when both the electric power steering devices 41 A and 41 B include torque sensors, the steering torque can be recognized in both the control apparatuses 1 A and 1 B.

Braking Operation Amount

The control apparatus 1 A includes the operation detection sensor 34 b . The control apparatus 1 B includes the pressure sensor 35 . Both can be used to detect the braking operation amount of the driver. On the other hand, the operation detection sensor 34 b is used to control the distribution of the braking force by the four brake devices 51 and the braking force by regenerative braking of the motor M, and the pressure sensor 35 is used for posture control and the like. Although the sensors are common concerning detection of the braking operation amount, the use purposes are different from each other.

[Power Supply]

The control apparatus 1 A receives power supply from the power supply 7 A, and the control apparatus 1 B receives power supply from the power supply 7 B. Since the power is supplied to any one of the control apparatuses 1 A and 1 B even in a case in which the power supply of one of the power supply 7 A and the power supply 7 B is shut down or lowers, it is possible to more reliably ensure the power supply and improve the reliability of the control system 1 . If the power supply of the power supply 7 A is shut down or lowers, it is difficult to perform communication between the ECUs via the gateway GW provided in the control apparatus 1 A. However, in the control apparatus 1 B, the ECU 21 B can communicate with the ECUs 22 B to 24 B via the communication line L 2 .

[Redundancy in Control Apparatus 1 A]

The control apparatus 1 A includes the ECU 20 A that performs automated driving control, and the ECU 29 A that performs traveling support control. That is, the control apparatus 1 A includes two control units configured to perform traveling control.

<Examples of Control Functions>

Control functions executable by the control apparatus 1 A or 1 B include traveling-associated functions associated with control of driving, braking, and steering of the vehicle V, and notification functions associated with a notification of information to the driver.

Examples of traveling-associated functions are lane maintaining control, lane departure suppression control (lane deviation suppression control), lane change control, preceding vehicle follow control, collision reduction brake control, and erroneous start suppression control. Examples of the notification functions are adjacent vehicle notification control and preceding vehicle start notification control.

Lane maintaining control is one of control processes for the position of the vehicle with respect to a lane. This control makes the vehicle travel automatically (without depending on the driving operation of the driver) on a traveling track set in a lane. Lane departure suppression control is one of control processes for the position of the vehicle with respect to a lane. A white line or a median strip is detected, and steering is automatically performed so the vehicle does not pass across the line. As described above, lane departure suppression control and lane maintaining control are different functions.

Lane change control is control of automatically moving the vehicle from the lane on which the vehicle is traveling to an adjacent lane. Preceding vehicle follow control is control of automatically following another vehicle traveling ahead of the self-vehicle. Collision reduction brake control is control of automatically braking the vehicle and supporting collision avoidance in a case in which the possibility of collision against an obstacle ahead of the vehicle rises. Erroneous start suppression control is control of limiting acceleration of the vehicle in a vehicle stop state in a case in which the acceleration operation by the driver is a predetermined amount or more, and suppresses abrupt start.

Adjacent vehicle notification control is control of notifying the driver of the presence of another vehicle traveling on the adjacent lane adjacent to the traveling lane of the self-vehicle. The driver is notified of, for example, the presence of another vehicle traveling on a side or on a rear side of the self-vehicle. Preceding vehicle start notification control is control of notifying that the self-vehicle and another vehicle ahead are in a stop state, and another vehicle ahead has started. These notifications can be made by the above-described in-vehicle notification devices (the information output device 43 A and the information output device 44 B).

The ECU 20 A, the ECU 29 A, and the ECU 21 B can share and execute these functions. Which control function is to be assigned to which ECU can appropriately be selected.

<Steering Control>

FIG. 4 is a view for explaining the concept of steering control according to this embodiment. The same reference numerals as in FIGS. 1 and 2 denote the similar constituent elements. As described above, in the vehicle V according to this embodiment, two cameras 32 A (cameras 32 A- 1 and 32 A- 2 ) are installed to acquire peripheral information on the front side. The installation positions of the cameras 32 A- 1 and 32 A- 2 are different. For this reason, even if they acquire peripheral information (images) at the same timing, a difference is generated in the peripheral information. Two cameras 32 A installed in the width direction of the vehicle like the cameras 32 A shown in FIG. 1 will be described here as an example. However, the present invention is not limited to this, and a combination of a plurality of cameras (for example, the cameras 32 A and the cameras 31 ) provided in the height direction may be used. These cameras can acquire peripheral information (images) in the same direction. In other words, the image capturing ranges of the two cameras 32 A at least partially overlap.

The traveling support ECU 29 A is an ECU of the active system and is used when normal traveling support is performed. The traveling support ECU 29 A acquires information (for example, a high-definition map) from the information ECU 25 A. As the information here, for example, the position or shape (the vehicle width, the bending state, or the like) of a white line on a road, or the like is used.

The traveling support ECU 21 B is an ECU of the redundant system. If, for example, a certain failure has occurred in the control of the traveling support ECU 29 A, the traveling support ECU 21 B performs control in place of the traveling support ECU 29 A. Information (image) acquired by the camera 32 A- 1 and information (image) acquired by the camera 32 A- 2 are input to the traveling support ECU 29 A. Information (image) acquired by the camera 32 A- 2 is input to the traveling support ECU 21 B.

Control signals of the traveling support ECU 29 A and the traveling support ECU 21 B are input to the steering ECUs 22 . Normally, the signal from the traveling support ECU 29 A is used in the steering ECUs 22 . At the time of a failure or the like in the traveling support ECU 29 A, the signal for the traveling support ECU 21 B is used.

In this embodiment, the traveling support ECU 29 A and the traveling support ECU 21 B can issue an instruction concerning steering angle control to the steering ECU 22 . The processing contents when issuing the instruction are different. For example, the traveling support ECU 29 A performs processing using map information and traveling contents (history information) so far, and outputs an instruction concerning the steering angle to the steering ECUs 22 . Additionally, in a normal state, the traveling support ECU 29 A performs steering angle control using information (image) from the camera 32 A- 1 and does not use information (image) from the camera 32 A- 2 for the steering angle control. On the other hand, the traveling support ECU 21 B performs steering angle control based on information (image) from the camera 32 A- 2 , but does not use, for example, map information or history information before a predetermined time.

Note that as for each control, the present invention is not limited to use of the above-described information, and another arrangement may be used. In this embodiment, the steering angle ECU 22 can identify which traveling support ECU has issued the instruction.

FIG. 5 is a view for explaining variations in a white line recognition state at the time of switching of the camera and steering angle control in traveling-associated functions. Lane maintaining control will be described here as an example. In FIG. 5, 5 a shows the positions of white lines extracted based on images acquired by the cameras. The position of the white line here is, for example, the position of the white line several tens meters ahead of the self-vehicle. Hence, a position apart from the self-vehicle by a predetermined distance may be used as the detection position of the white line. The ordinate represents an input value [m] concerning the white line, and the abscissa represents time [s]. On the ordinate, “0” indicates the center position of the self-vehicle. As the difference (relative position) from the center position, a white line position on the left side is indicated as plus (+), and a white line position on the right side is indicated as minus (−). Hence, a graph 501 represents input values corresponding to the white line on the left side of the vehicle, and a graph 502 represents input values corresponding to the white line on the right side of the vehicle.

Note that the input value here has been described as a relative value with respect to the center of the vehicle. However, the present invention is not limited to this. For example, the input value may be the difference from the center position of a camera. In this case, the input value is corrected based on the difference between the installation position of the camera and the center position of the vehicle.

In 5 a of FIG. 5 , in a range A, lane maintaining control is performed using the camera 32 A- 1 of the active system. After that, switching to the camera 32 A- 2 of the redundant system is performed at a timing indicated by an arrow 503 . In this case, since the installation positions of the cameras are different, as described above, the detection result changes in the same white line. In addition, the cameras have individual differences (dispersions). Because of such differences, a shift occurs in the input value representing the white line immediately after the switching. Here, a shift of about 1 m occurs in the leftward direction.

In FIG. 5, 5 b shows the control amount of the steering angle in steering angle control of the vehicle. The ordinate represents the control amount [deg] of steering angle control, and the abscissa represents time. If it is detected that the position of the white line shifts leftward, as shown in 5 a of FIG. 5 , steering is controlled leftward, as indicated by a graph 504 in 5 b of FIG. 5 . Then, steering in the leftward and rightward directions is repeated to cope with the image after switching, thereby stabilizing traveling. Additionally, the steering ECU performs correction of the input values according to the installation positions of the cameras in accordance with the switching of the camera. With these control operations, control corresponding to the camera after the switching is performed. As a result, the traveling position before the switching of the camera (range A) and the traveling position after the switching of the camera (range B) become equal, and stable traveling (lane maintaining) is continued. At this time, in the range B, the control amount of the steering becomes large in accordance with the switching of the camera. After stabilizing, the control amount of steering becomes the same as in the range A, as indicated by a range C.

Here, when the switching of the camera as indicated by the arrow 503 has occurred, if the state is abruptly brought close to the state before switching, the traveling behavior of the vehicle V becomes unstable. For example, if the control amount of steering is abruptly increased in accordance with the switching, the acceleration in the lateral direction during traveling increases, resulting in an influence on the comfort of ride of an occupant, traveling stability, and the like.

In this embodiment, during a predetermined period immediately after the occurrence of the switching of the camera, limitations are added to the control amount concerning traveling support. Note that in this embodiment, a predetermined limitation is added to the control amount even in the range A or the range C shown in FIG. 5 . A limitation higher than this limitation is added in the range B.

<Control Procedure>

FIG. 6 is a flowchart showing a control procedure according to this embodiment. This processing procedure is started when, for example, a driving support instruction is made by the driver of the vehicle V, or the vehicle is switched to a mode to perform driving support. In each control, various kinds of ECUs and the like as described above, which are provided in the vehicle, cooperatively perform processing. Here, for the descriptive simplicity, the processing entity is shown as the control system 1 of the vehicle V.

In step S 601 , the control system 1 starts driving support control of the vehicle V. The driving support control here includes the above-described traveling-associated functions. In addition, as peripheral information used for driving support control, white line information based on peripheral information acquired from the camera 32 A is used.

In step S 602 , the control system 1 determines whether switching of the camera is performed. That is, the control system 1 determines whether peripheral information used in driving support control is changed from information acquired by the camera 32 A- 1 to peripheral information acquired by the camera 32 A- 2 that is the redundant system. This switching is done in a case in which, for example, a failure has occurred in the camera 32 A- 1 or the traveling support ECU 29 A. In the arrangement shown in FIG. 4 , if switching to the camera 32 A- 2 is done, the traveling support ECU 21 B that is the redundant system is used. Upon determining that the switching of the camera is performed (YES in step S 602 ), the process advances to step S 603 . Upon determining that the switching is not performed (NO in step S 602 ), driving support control is continued, and monitoring concerning switching of the camera is continued.

In step S 603 , the control system 1 determines, in accordance with the switching of the camera, whether the difference (white line gap) between the position of a white line detected before the switching and the position of the white line detected after the switching is equal to or larger than a predetermined threshold. The predetermined threshold here is defined in advance and stored in a storage unit. In addition, the predetermined threshold to be used may be decided based on the installation position of each camera or the traveling state (the speed, the traveling position, or the like) of the vehicle. Upon determining that the difference is equal to or larger than the predetermined threshold (YES in step S 603 ), the process advances to step S 604 . Upon determining that the difference is smaller than the predetermined threshold (NO in step S 603 ), the process returns to step S 602 to continue driving support control without limiting the steering control amount. Note that in a case in which the system has already learned the white line gap (left/right difference) generated by switching of the camera, driving support control may be continued without limiting the steering control amount.

In step S 604 , the control system 1 limits the control amount of steering control. That is, if the control amount controllable by normal driving support control is directly permitted immediately after the switching of the camera, the traveling behavior of the vehicle V becomes unstable. To prevent this, the control amount of steering control is limited. The control amount limited here may be decided based on, for example, the difference between the installation positions of the cameras 32 A or the difference of acquirable images. Alternatively, the control amount may be decided based on the traveling speed of the vehicle V, the state of the road to travel, the presence/absence of a vehicle on the periphery, or the like. In addition, the control amount of steering may be limited on the side of the traveling support ECU 21 B or on the side of the steering ECU 22 .

In step S 605 , the control system 1 determines whether a predetermined time has elapsed after the steering control amount is limited. As the predetermined time here, for example, a specific value set in advance may be used, or the value may be decided from the traveling speed of the vehicle V. If the predetermined time has elapsed (YES in step S 605 ), the process advances to step S 606 . If the predetermined time has not elapsed (NO in step S 605 ), monitoring is continued until the time elapses.

In step S 606 , the control system 1 cancels the limitation of the steering control amount performed in step S 604 . Then, the process returns to step S 602 to continue driving support control.

This processing procedure ends when, for example, a driving support cancel instruction is made by the driver of the vehicle V, or the vehicle is switched to a mode not to perform driving support. In this embodiment, the limitation of the steering control amount is canceled after the predetermined time has elapsed from the limitation. However, the present invention is not limited to this. For example, the limitation may be canceled when the control amount of steering becomes equal to that in the range A before the switching, as indicated by the range C in FIG. 5 . Alternatively, the limitation may be canceled after the vehicle V has traveled a predetermined distance after the limitation.

<Limitation of Steering Control Amount>

The limitation of the steering control amount according to this embodiment will be described. In the limitation method according to this embodiment, the change amount with respect to the preceding steering control amount (the instruction value of the steering angle) is limited. For example, the period of steering angle instruction is set to 10 [ms]. The preceding steering angle control amount is assumed to be 10 [deg]. In this case, the upper limit of the control amount of the steering angular velocity is set to 30 [deg/s]. As a result, the current steering angle control amount is limited to the range of 9.7 to 10.3 [deg] (10±0.3 [deg]). Note that the period of steering angle instruction is an example, and is not limited to this. In addition, the steering angular velocity to be limited may be changed in accordance with the traveling speed of the vehicle V or the like.

FIG. 7 shows an example of the steering angle control amount limitation method. In FIG. 7 , the ordinate represents an input value input as a steering angle instruction value, and the abscissa represents an output value as a control amount to control the vehicle V. As one example, the input value to the traveling support ECU 21 B and the output value will be described here. However, the steering ECU 22 may perform the processing.

A line 701 represents a threshold used when adding a limitation. A line 702 represents the relationship between the input value and the output value in a case in which no limitation is added. In this case, the input value is directly used as the output value. Each of lines 703 and 704 represents the relationship between the input value and the output value in a case in which a limitation is added. The line 703 indicates a case in which a limitation is added to a portion where the input value exceeds the threshold such that the output value becomes equal (or almost equal) to the threshold. The line 704 indicates a case in which the input value is corrected and reduced within the entire range of the input value such that the value becomes equal to or smaller than the threshold. When performing control represented by the line 704 , the output value can be decided using, for example, a conversion table or the like. Additionally, although not illustrated in FIG. 7 , when adding a limitation, if the input value is smaller than a predetermined value, the input value may directly be used as the output value. If the input value is larger than the predetermined value, the control amount may be suppressed by performing correction represented by the line 703 .

An arrangement that limits the change amount of the steering angular velocity between the preceding control and the current control has been described above. However, the present invention is not limited to this. For example, a threshold may be set for the instruction value of the steering angle, and the steering angle control amount may be limited based on the threshold. In addition, a setting may be done to lower the amount to be limited stepwise along with the elapse of time from the start of the limitation.

In the above embodiment, two cameras have been described as an example. However, the present invention is not limited to this. For example, the same processing as described above can be applied even in a case in which switching occurs among three or more cameras.

Additionally, in the above embodiment, a camera has been described as an example of the means for acquiring peripheral information. However, the present invention is not limited to this. For example, the present invention may be applied in a case in which switching of another detection means such as a sensor or a lidar configured to acquire peripheral information to be used for driving support control occurs.

As described above, according to this embodiment, it is possible to stabilize the behavior of the vehicle even if the camera configured to acquire peripheral information used in driving support control is switched when driving support control is performed. In addition, when the behavior of the vehicle stabilizes, the uneasiness of the occupant of the vehicle can be eliminated.

Summary of Embodiment

1. A vehicle control system (for example, 1) according to the above embodiment is

a vehicle control system provided with first detection unit and second detection unit (for example, 32 A) configured to acquire peripheral information of a self-vehicle (for example, V), comprising:

a control unit (for example, 29 A, 21 B, 22 ) configured to perform traveling control of the self-vehicle using the peripheral information,

wherein when switching from a first traveling state using peripheral information detected by the first detection unit to a second traveling state using peripheral information detected by the second detection unit is performed, the control unit suppresses a control amount based on the peripheral information of the self-vehicle.

According to this embodiment, it is possible to stabilize the behavior of the vehicle even if the detection unit for acquiring peripheral information used in driving support control is switched.

2. In the above embodiment, the first detection unit and the second detection unit comprise a first camera and a second camera, whose image capturing ranges at least partially overlap, and

the first camera and the second camera are provided at different positions in a width direction of the self-vehicle.

According to this embodiment, it is possible to stabilize the behavior of the vehicle even if the camera is switched when the acquired peripheral information is different depending on the installation position of the camera.

3. In the above embodiment, a first threshold for the control amount based on the peripheral information used in one of the first traveling state and the second traveling state is larger than a second threshold for the control amount based on the peripheral information used in a predetermined period after switching from the first traveling state to the second traveling state.

According to this embodiment, the control amount can be switched in accordance with the traveling state, and the stability of the vehicle in traveling control can be improved.

4. In the above embodiment, the predetermined period is one of a period until a predetermined time elapses after switching from the first traveling state to the second traveling state and a period until the self-vehicle travels a predetermined distance after switching from the first traveling state to the second traveling state.

According to this embodiment, the stability of the vehicle in traveling control can be improved by controlling the period of adding a limitation starting from the switching of the detection unit.

5. In the above embodiment, the control amount is a control amount concerning steering.

According to this embodiment, it is possible to stabilize the behavior of the vehicle concerning steering even if the detection unit configured to acquire the peripheral information used in driving support control is switched.

6. In the above embodiment, the peripheral information is a position of a white line on a road on which the self-vehicle travels.

According to this embodiment, it is possible to stabilize control based on the white line even if the detection unit configured to acquire the peripheral information used in driving support control is switched.

7. A control method of a vehicle according to the above embodiment is a control method of a vehicle (for example, V) provided with first detection unit and second detection unit (for example, 32 A) configured to acquire peripheral information of a self-vehicle, comprising:

performing traveling control by suppressing a control amount based on the peripheral information of the self-vehicle when switching from a first traveling state using peripheral information detected by the first detection unit to a second traveling state using peripheral information detected by the second detection unit is performed.

In this embodiment, it is possible to stabilize the behavior of the vehicle even if the detection unit configured to acquire peripheral information used in driving support control is switched.

The present invention is not limited to the above embodiments, and various changes and modifications can be made within the spirit and scope of the present invention.