JP7748906B2 - Vehicle control device, vehicle control method, and program - Google Patents

Description

The present invention relates to a vehicle control device, a vehicle control method, and a program.

Technologies for controlling the steering angular velocity applied to vehicle steering devices are known. For example, Patent Document 1 discloses a technology that limits the steering angular velocity command value to a limit value corresponding to the vehicle speed in order to suppress sudden steering.

JP 2018-122680 A

However, with the technology described in Patent Document 1, there are cases where limiting processing is applied to the steering angle speed against the intention of the vehicle driver, which can hinder driving operations by the driver.

The present invention was made in consideration of these circumstances, and one of its objectives is to provide a vehicle control device, vehicle control method, and program that can control the steering angular speed of a vehicle's steering device without interfering with the driver's driving operations.

A vehicle control device, a vehicle control method, and a program according to the present invention employ the following configuration.
(1): A vehicle control device according to one aspect of the present invention includes an acquisition unit that acquires a positional relationship between a vehicle and a lane in which the vehicle is traveling; a control unit that causes a steering device of the vehicle to output a steering torque within a range of a steering angular velocity upper limit value based on the positional relationship, for causing the vehicle to travel within the lane; and an adjustment unit that adjusts the value of the steering angular velocity upper limit value based on a steering direction input by an occupant of the vehicle and a steering direction that the control unit causes the steering device to output.

(2): In the above aspect (1), the adjustment unit identifies the direction of the steering torque or the direction of the steering speed of the steering device as the steering direction input by the vehicle occupant or the steering direction that the control unit causes the steering device to output.

(3): In the above aspect (1) or (2), the adjustment unit increases the steering angular velocity upper limit value when the steering direction input by the vehicle occupant matches the steering direction that the control unit causes the steering device to output.

(4): In any of the above aspects (1) to (3), the adjustment unit maintains the steering angular velocity upper limit constant when the steering direction input by the vehicle occupant does not match the steering direction that the control unit causes the steering device to output.

(5): In another aspect of the present invention, a vehicle control method includes a computer acquiring a positional relationship between a vehicle and a lane in which the vehicle is traveling, and, based on the positional relationship, causing a steering device of the vehicle to output a steering torque within a steering angular speed upper limit value range for causing the vehicle to travel within the lane, and adjusting the value of the steering angular speed upper limit value based on the steering direction input by the vehicle occupant and the steering direction to be output by the steering device.

(6): A program according to another aspect of the present invention causes a computer to acquire the positional relationship between a vehicle and the lane in which the vehicle is traveling, and based on the positional relationship, causes the steering device of the vehicle to output a steering torque within a steering angular speed upper limit value range for causing the vehicle to travel within the lane, and adjusts the value of the steering angular speed upper limit value based on the steering direction input by the vehicle occupant and the steering direction to be output by the steering device.

According to aspects (1) to (6), the steering angular speed of the vehicle's steering device can be controlled without interfering with the driver's driving operation.

1 is a configuration diagram of a vehicle system 1 using a vehicle control device 100 according to an embodiment. 10 is a diagram showing an example of a positional relationship acquired by an acquisition unit 110. FIG. FIG. 10 is a diagram illustrating an example of an LKAS operation executed by a control unit 120. 10 is an example of a graph showing a steering angular velocity upper limit value adjusted by an adjustment unit 130. 4 is a flowchart showing an example of the flow of operations executed by the vehicle control device 100.

Embodiments of the vehicle control device, vehicle control method, and program of the present invention will be described below with reference to the drawings.

[Overall configuration]
1 is a configuration diagram of a vehicle system 1 using a vehicle control device according to an embodiment. The vehicle on which the vehicle system 1 is installed may be, for example, a two-wheeled, three-wheeled, or four-wheeled vehicle, and its drive source may be an internal combustion engine such as a diesel engine or a gasoline engine, an electric motor, or a combination of these. The electric motor operates using power generated by a generator connected to the internal combustion engine, or discharged power from a secondary battery or a fuel cell.

The vehicle system 1 includes, for example, a camera 10, a radar device 12, a LIDAR (Light Detection and Ranging) device 14, an object recognition device 16, a communication device 20, an HMI (Human Machine Interface) 30, vehicle sensors 40, a driving operator 50, a vehicle control device 100, a driving force output device 200, a braking device 210, and a steering device 220. These devices and equipment are connected to each other via multiplexed communication lines such as a CAN (Controller Area Network) communication line, serial communication lines, a wireless communication network, etc. Note that the configuration shown in Figure 1 is merely an example, and some of the configuration may be omitted, or additional configuration may be added.

Camera 10 is a digital camera that uses a solid-state imaging element such as a CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor). Camera 10 is attached to any location on the vehicle (hereinafter referred to as host vehicle M) in which vehicle system 1 is installed. When capturing images of the front, camera 10 is attached to the top of the front windshield, the back of the rearview mirror, or the like. Camera 10, for example, periodically captures images of the surroundings of host vehicle M. Camera 10 may also be a stereo camera.

The radar device 12 emits radio waves such as millimeter waves around the vehicle M and detects radio waves reflected by objects (reflected waves) to detect at least the position (distance and direction) of the object. The radar device 12 may be mounted at any location on the vehicle M. The radar device 12 may also detect the position and speed of an object using the FM-CW (Frequency Modulated Continuous Wave) method.

The LIDAR 14 irradiates the area around the vehicle M with light (or electromagnetic waves with wavelengths similar to light) and measures the scattered light. The LIDAR 14 detects the distance to the target based on the time between light emission and light reception. The irradiated light is, for example, pulsed laser light. The LIDAR 14 can be attached to any location on the vehicle M.

The object recognition device 16 performs sensor fusion processing on the detection results from some or all of the camera 10, radar device 12, and LIDAR 14 to recognize the position, type, speed, etc. of the object. The object recognition device 16 outputs the recognition results to the vehicle control device 100. The object recognition device 16 may output the detection results from the camera 10, radar device 12, and LIDAR 14 directly to the vehicle control device 100. The object recognition device 16 may be omitted from the vehicle system 1.

The communication device 20 communicates with other vehicles in the vicinity of the vehicle M, for example, using a cellular network, Wi-Fi network, Bluetooth (registered trademark), or DSRC (Dedicated Short Range Communication), or communicates with various server devices via a wireless base station.

The HMI 30 presents various information to the occupants of the vehicle M and accepts input operations from the occupants. The HMI 30 includes various display devices, speakers, buzzers, touch panels, switches, keys, etc.

The vehicle sensors 40 include a vehicle speed sensor that detects the speed of the host vehicle M, an acceleration sensor that detects acceleration, a yaw rate sensor that detects angular velocity around a vertical axis, and a direction sensor that detects the orientation of the host vehicle M.

The driving controls 50 include, for example, a steering wheel 52, an accelerator pedal, a brake pedal, a shift lever, and other controls. The driving controls 50 are equipped with sensors that detect the amount of operation or the presence or absence of operation, and the detection results are output to the vehicle control device 100 or some or all of the driving force output device 200, the brake device 210, and the steering device 220. The controls do not necessarily have to be annular and may take the form of an irregular steering wheel, a joystick, a button, or the like. The steering wheel 52 is equipped with a steering grip sensor 54. The steering grip sensor 54 is realized using a capacitance sensor or the like and outputs a signal to the vehicle control device 100 that can detect whether the driver is gripping the steering wheel 52 (meaning that the steering wheel is in contact with the steering wheel in a state where force can be applied). As described below, in addition to receiving steering torque input by the driver, the steering wheel 52 also outputs steering torque in response to instructions from the control unit 120 via an actuator.

The vehicle control device 100 includes, for example, an acquisition unit 110, a control unit 120, and an adjustment unit 130. The acquisition unit 110, the control unit 120, and the adjustment unit 130 are each implemented by a hardware processor, such as a CPU (Central Processing Unit), executing a program (software). Some or all of these components may be implemented by hardware (including circuitry) such as an LSI (Large Scale Integration), ASIC (Application Specific Integrated Circuit), FPGA (Field-Programmable Gate Array), or GPU (Graphics Processing Unit), or may be implemented by a combination of software and hardware. The program may be stored in advance on a storage device (storage device with a non-transitory storage medium) such as an HDD or flash memory of the vehicle control device 100, or may be stored on a removable storage medium such as a DVD or CD-ROM, and installed on the HDD or flash memory of the vehicle control device 100 by inserting the storage medium (non-transitory storage medium) into a drive device. The functions of the acquisition unit 110, control unit 120, and adjustment unit 130 will be described later.

The driving force output device 200 outputs driving force (torque) to the drive wheels to drive the vehicle. The driving force output device 200 includes, for example, a combination of an internal combustion engine, an electric motor, and a transmission, and an ECU (Electronic Control Unit) that controls these. The ECU controls the above components in accordance with information input from the control unit 120 or information input from the driving operator 50.

The brake device 210 includes, for example, a brake caliper, a cylinder that transmits hydraulic pressure to the brake caliper, an electric motor that generates hydraulic pressure in the cylinder, and a brake ECU. The brake ECU controls the electric motor according to information input from the control unit 120 or information input from the driving operator 50, so that brake torque corresponding to the braking operation is output to each wheel. The brake device 210 may be equipped with a backup mechanism that transmits hydraulic pressure generated by operation of the brake pedal included in the driving operator 50 to the cylinder via a master cylinder. Note that the brake device 210 is not limited to the configuration described above, and may also be an electronically controlled hydraulic brake device that controls an actuator according to information input from the control unit 120 to transmit hydraulic pressure from the master cylinder to the cylinder.

The steering device 220 includes, for example, a steering ECU and an electric motor. The electric motor applies force to a rack and pinion mechanism to change the direction of the steered wheels. The steering ECU drives the electric motor to change the direction of the steered wheels in accordance with information input from the control unit 120 or information input from the driving operator 50.

[Operation of vehicle control device]
The acquisition unit 110 acquires the positional relationship between the host vehicle M and the lane in which the host vehicle M is traveling, based on information received from the object recognition device 16. Fig. 2 is a diagram showing an example of the positional relationship acquired by the acquisition unit 110. First, the acquisition unit 110 acquires the road dividing line RL of the traveling lane L1 in which the host vehicle M is traveling, based on information received from the object recognition device 16 (or an image showing the periphery of the host vehicle M captured by the camera 10).

Next, the acquisition unit 110 calculates the center line CL between the road dividing lines RL on both sides of the host vehicle M and acquires the positional relationship between the host vehicle M and the center line CL. For example, the acquisition unit 110 draws a perpendicular line from the center of gravity of the host vehicle M to the center line CL and acquires the length of the perpendicular line as the distance between the host vehicle M and the center line CL. Furthermore, for example, if the center of gravity of the host vehicle M is located to the right of the center line CL, the acquisition unit 110 recognizes that the host vehicle M is located on the right side of the driving lane L1. Conversely, if the center of gravity of the host vehicle M is located to the left of the center line CL, the acquisition unit 110 recognizes that the host vehicle M is located on the left side of the driving lane L1. In the case of Figure 2, the host vehicle M is traveling on the center line CL, so the acquisition unit 110 recognizes that the host vehicle M is located in the center of the driving lane L1.

Based on the positional relationship acquired by the acquisition unit 110, the control unit 120 outputs to the steering wheel 52 of the host vehicle M a steering torque within the range of the upper steering angular speed limit value for driving the host vehicle M within the driving lane L1 (e.g., on the center line CL of the driving lane L1). This operation of outputting to the steering wheel 52 a steering torque for driving the host vehicle M within the driving lane L1 is referred to as LKAS (Lane Keeping Assist System) operation.

Figure 3 is a diagram showing an example of LKAS operation executed by the control unit 120. Figure 3 illustrates a scene in which the host vehicle M is traveling a predetermined distance to the right of the center line CL of the driving lane L1. At this time, the acquisition unit 110 acquires, based on information received from the object recognition device 16, a positional relationship indicating that the host vehicle M is traveling a predetermined distance to the right of the center line CL. In response, the control unit 120 outputs a steering torque to the steering wheel 52 to steer the host vehicle M along the center line CL, based on the positional relationship acquired by the acquisition unit 110. In the case of Figure 3, the control unit 120 outputs a steering torque to the steering wheel 52 to steer the host vehicle M to the left.

In this way, the control unit 120 outputs a steering torque to the steering wheel 52 of the host vehicle M within the steering angular speed upper limit range to drive the host vehicle M within the driving lane L1. However, in general, with an LKAS, if the driver inputs a steering torque to the steering wheel 52 that exceeds the steering angular speed upper limit, the control by the control unit 120 will be interrupted by a steering operation override. This may feel to the driver as if the brakes are being applied at a steering speed that is different from the intended steering speed, which may hinder the driver's driving of the host vehicle M.

With the above circumstances as a background, the adjustment unit 130 adjusts the value of the steering angular velocity upper limit based on the steering direction (i.e., rightward or leftward) input by the driver of the vehicle M and the steering direction that the control unit 120 causes the steering wheel 52 to output. For example, the adjustment unit 130 can identify the direction of the steering torque of the steering wheel 52 or the direction of the steering speed as these two steering directions. In the following explanation, an example will be described in which the adjustment unit 130 identifies the direction of the steering torque of the steering wheel 52 as the steering direction and performs control, but the processing is similar when identifying the direction of the steering speed as the steering direction.

Figure 4 is an example of a graph showing the steering angular velocity upper limit value adjusted by the adjustment unit 130. In Figure 4, the horizontal axis represents the steering torque input by the driver of the host vehicle M, and the vertical axis represents the value of the steering angular velocity upper limit value. The adjustment unit 130 receives the steering torque input to the steering wheel 52 by the driver of the host vehicle M, and if the direction of the received steering torque matches the direction of the steering torque that the control unit 120 causes the steering wheel 52 to output, the adjustment unit 130 increases the steering angular velocity upper limit value according to the magnitude of the received steering torque.

For example, in FIG. 4, the symbol RR represents the region in which the adjustment unit 130 increases the steering angular velocity upper limit value in the right direction when the received steering torque direction is rightward. Similarly, the symbol LR represents the region in which the adjustment unit 130 increases the steering angular velocity upper limit value in the left direction when the received steering torque direction is leftward. Region RR (region LR) can be said to be the region in which, in conventional technology, steering to the right (left) by the LKAS is insufficient, and an override occurs when the driver manually increases the steering torque.

In contrast, in the present invention, when the steering torque input to the steering wheel 52 by the driver of the vehicle M is to the right (left) and the steering direction by the LKAS matches, the adjustment unit 130 increases the steering angular speed upper limit value in the right (left) direction. This improves the continuation rate of LKAS control by the control unit 120 without causing an override, and prevents interference with driving operations due to control interruptions. Furthermore, even on roads that conventional LKAS operation cannot follow and require the driver to perform large steering operations (e.g., corners, roundabouts, intersections, etc.), the steering angular speed upper limit value increases in the same direction in response to light steering torque applied by the driver, thereby reducing the burden on the driver when steering.

The adjustment unit 130 maintains the steering angular velocity upper limit value when the direction of the steering torque input to the steering wheel 52 by the driver of the host vehicle M does not match the direction of the steering torque that the control unit 120 causes the steering wheel 52 to output. For example, the second quadrant of the graph in FIG. 4 represents a state in which the direction of the steering torque input by the driver of the host vehicle M is leftward, while the direction of the steering torque that the control unit 120 causes the steering wheel 52 to output is rightward (i.e., positive). Similarly, the fourth quadrant of the graph in FIG. 4 represents a state in which the direction of the steering torque input by the driver of the host vehicle M is rightward, while the direction of the steering torque that the control unit 120 causes the steering wheel 52 to output is leftward (i.e., negative). In this way, by maintaining the steering angular velocity upper limit value when the steering torque directions do not match, the behavior of the host vehicle M can be suppressed, giving the driver time to deal with the problem, even if a steering control malfunction occurs, for example, due to erroneous recognition by the camera 10.

Next, the flow of operations executed by the vehicle control device 100 will be described with reference to Figure 5. Figure 5 is a flowchart showing an example of the flow of operations executed by the vehicle control device 100. First, the acquisition unit 110 acquires the positional relationship between the host vehicle M and the driving lane based on information received from the object recognition device 16 (step S100).

Next, the adjustment unit 130 acquires the value of the steering torque input to the steering wheel 52 by the driver (step S102). Next, the adjustment unit 130 acquires the value of the steering torque instructed by the control unit 120 (step S104). Next, the adjustment unit 130 determines whether the direction of the steering torque input to the steering wheel 52 by the driver and the direction of the steering torque instructed by the control unit 120 match (step S106).

If it is determined that the direction of the steering torque input to the steering wheel 52 by the driver matches the direction of the steering torque instructed by the control unit 120, the adjustment unit 130 increases the steering angular velocity upper limit value in accordance with the magnitude of the input steering torque (step S108). On the other hand, if it is determined that the direction of the steering torque input to the steering wheel 52 by the driver does not match the direction of the steering torque instructed by the control unit 120, the adjustment unit 130 maintains the steering angular velocity upper limit value at a specified value (step S110).

Next, the control unit 120 outputs a steering torque to the steering wheel 52 to perform LKAS operation within the range of the steering angular velocity upper limit set by the adjustment unit 130 (step S112). This completes the processing of this flowchart. Note that in the above flowchart, the processing of steps S100, S102, and S104 is performed sequentially, but these processes may also be performed in parallel.

According to the present embodiment described above, when the direction of the steering torque input by the vehicle occupant matches the direction of the steering torque instructed by the control unit that executes the LKAS operation, the upper limit value of the steering angular velocity of the steering torque output by the LKAS operation is increased. This makes it possible to control the steering angular velocity of the vehicle's steering device without interfering with the driver's driving operation.

The above-described embodiment can be expressed as follows.
a storage device storing a program;
a hardware processor;
The hardware processor executes the program stored in the storage device to acquire a positional relationship between a vehicle and a lane in which the vehicle is traveling,
outputting a steering torque to a steering device of the vehicle within a range of a steering angular speed upper limit value based on the positional relationship, for causing the vehicle to travel within the lane;
adjusting the steering angular velocity upper limit value based on the steering direction input by the vehicle occupant and the steering direction that the control unit causes the steering device to output;
The vehicle control device is configured as follows.

The above describes the form for carrying out the present invention using an embodiment, but the present invention is in no way limited to such an embodiment, and various modifications and substitutions can be made without departing from the spirit of the present invention.

10 Camera 12 Radar device 14 LIDAR
16 Object recognition device 20 Communication device 30 HMI
40 Vehicle sensor 50 Driving operator 52 Steering wheel 54 Steering grip sensor 100 Vehicle control device 110 Acquisition unit 120 Control unit 130 Adjustment unit 200 Traveling driving force output device 210 Brake device 220 Steering device

Claims (6)

an acquisition unit that acquires a positional relationship between a vehicle and a lane in which the vehicle is traveling;
a control unit that outputs a steering torque to a steering device of the vehicle based on the positional relationship, within a range of a steering angular speed upper limit value, for causing the vehicle to travel within the lane;
an adjustment unit that adjusts the steering angular velocity upper limit value based on a steering direction input by an occupant of the vehicle and a steering direction that the control unit causes the steering device to output,
Vehicle control device. The adjustment unit specifies the direction of the steering torque or the direction of the steering speed of the steering device as the steering direction input by an occupant of the vehicle or the steering direction that the control unit causes the steering device to output.
The vehicle control device according to claim 1 . the adjustment unit increases the steering angular velocity upper limit value when the steering direction input by the occupant of the vehicle coincides with the steering direction that the control unit causes the steering device to output.
The vehicle control device according to claim 1 or 2. the adjustment unit maintains the value of the steering angular velocity upper limit constant when the steering direction input by the occupant of the vehicle does not match the steering direction that the control unit causes the steering device to output.
The vehicle control device according to any one of claims 1 to 3. The computer
Obtaining a positional relationship between a vehicle and a lane in which the vehicle is traveling;
outputting a steering torque to a steering device of the vehicle within a range of a steering angular speed upper limit value based on the positional relationship, for causing the vehicle to travel within the lane;
adjusting the steering angular velocity upper limit value based on a steering direction input by an occupant of the vehicle and a steering direction to be output by the steering device;
Vehicle control method. On the computer,
acquiring a positional relationship between a vehicle and a lane in which the vehicle is traveling;
outputting a steering torque to a steering device of the vehicle within a range of a steering angular speed upper limit value based on the positional relationship, for causing the vehicle to travel within the lane;
adjusting the steering angular velocity upper limit value based on a steering direction input by an occupant of the vehicle and a steering direction to be output by the steering device;
program.