JP-2026075734-A - Vehicle steering assistance device, steering assistance method, and program thereof

Abstract

[Problem] To provide a steering assistance device for a vehicle that can perform steering guide assistance control even when driving on a circuit. [Solution] The steering support ECU (20) is applied to a vehicle (HV) equipped with a steering device (10) that applies a basic return torque, which is a torque that increases in magnitude as the steering angle increases and is in a direction that returns the steering wheel (11) to the neutral position. The steering support ECU (20) determines a target guide torque so that the steering angle (θact) is easily maintained within a predetermined target steering angle range that includes the target steering angle, and generates a torque in the electric motor (21) corresponding to the target guide torque. If the vehicle forward image acquired by the camera sensor (34) includes a curve boundary provided on the curved road portion of the circuit, the steering support ECU (20) determines the target driving line of the vehicle using the curve boundary and determines the target steering angle based on the determined target driving line. [Selection Diagram] Figure 1

Inventors

• 大森 光晟

Assignees

• トヨタ自動車株式会社

Dates

Publication Date

20260511

Application Date

20241023

Claims (5)

1. This applies to a vehicle equipped with a steering system that applies a basic return torque to the steering wheel, which is a torque that increases in magnitude as the steering angle (the amount of steering wheel operation) increases, and is a torque that returns the steering wheel to the neutral position. A camera sensor that acquires an image of the area in front of the vehicle by capturing the scene in front of the vehicle, An electric motor that generates torque to be applied to the steering wheel, A controller for controlling the aforementioned electric motor, Equipped with, The aforementioned controller, A target guide torque is determined to make it easier to maintain the steering angle within a predetermined target steering angle range that includes the target steering angle. The electric motor generates a torque corresponding to the target guide torque. In a steering assist system for a vehicle configured as follows, The aforementioned controller, When the steering angle is within the target steering angle range, the target guide torque is determined such that the ratio of the increase in torque applied to the steering wheel when the electric motor generates the target guide torque to the increase in the magnitude of the steering angle is greater than the ratio of the increase in torque applied to the steering wheel when the electric motor does not generate the target guide torque to the increase in the magnitude of the steering angle. The controller further, If the vehicle forward image includes a curved section boundary which is a road boundary provided in the curved section of the circuit, the target driving line of the vehicle is determined using the curved section boundary included in the vehicle forward image, and the target steering angle is determined based on the determined target driving line. It is configured in such a way. Steering assist device.
2. In the vehicle steering assist device according to claim 1, The aforementioned controller, A predetermined position on the side edge of the track at the boundary of the curved section is set as the target point, and the target driving line is determined based on the position of the vehicle, the direction of travel of the vehicle, and the target point. It is configured in such a way. Steering assist device.
3. A steering assistance method for a vehicle, applicable to a vehicle equipped with a steering system that applies a basic return torque to the steering wheel, which is a torque that increases in magnitude as the steering angle (the amount of steering wheel operation) increases, and is a torque that returns the steering wheel to the neutral position, wherein the torque ultimately applied to the steering wheel is adjusted by controlling an electric motor, A first step is to determine a target guide torque that makes it easier to maintain the steering angle within a predetermined target steering angle range that includes the target steering angle, A second step involves generating a torque in the electric motor corresponding to the target guide torque, Includes, The first step is, The step of determining the target guide torque is such that, when the steering angle is within the target steering angle range, the ratio of the increase in the magnitude of the torque applied to the steering wheel when the electric motor generates the target guide torque to the increase in the magnitude of the steering angle is greater than the ratio of the increase in the magnitude of the torque applied to the steering wheel when the electric motor does not generate the target guide torque to the increase in the magnitude of the steering angle. Furthermore, The first step is, If the forward-facing image of the vehicle acquired by a camera mounted on the vehicle includes a curved section boundary, which is a road boundary provided in the curved section of the circuit, the vehicle's target driving line is determined using the curved section boundary included in the forward-facing image of the vehicle, and the target steering angle is determined based on the determined target driving line. Steering assistance method.
4. In the vehicle steering assistance method described in claim 4, The first step is, The step involves setting a predetermined position on the side edge of the road boundary of the aforementioned line section as a target point, and determining the target driving line based on the position of the vehicle, the direction of travel of the vehicle, and the target point. Steering assistance method.
5. This program is applied to a vehicle equipped with a steering system that applies a basic return torque to the steering wheel, which is a torque that increases in magnitude as the steering angle (the amount of steering wheel operation) increases, and is a torque that returns the steering wheel to the neutral position, and causes a computer mounted on the vehicle to execute a step to adjust the torque ultimately applied to the steering wheel by controlling an electric motor. The program is sent to the computer, A first step is to determine a target guide torque that makes it easier to maintain the steering angle within a predetermined target steering angle range that includes the target steering angle, A second step involves generating a torque in the electric motor corresponding to the target guide torque, It is a program that executes, The first step is, The step of determining the target guide torque is such that, when the steering angle is within the target steering angle range, the ratio of the increase in the magnitude of the torque applied to the steering wheel when the electric motor generates the target guide torque to the increase in the magnitude of the steering angle is greater than the ratio of the increase in the magnitude of the torque applied to the steering wheel when the electric motor does not generate the target guide torque to the increase in the magnitude of the steering angle. Furthermore, The first step is, If the forward-facing image of the vehicle acquired by a camera mounted on the vehicle includes a curved section boundary, which is a road boundary provided in the curved section of the circuit, the vehicle's target driving line is determined using the curved section boundary included in the forward-facing image of the vehicle, and the target steering angle is determined based on the determined target driving line. program.

Description

This invention relates to a vehicle steering assistance device, a steering assistance method, and a program thereof, which assist the driver in steering the vehicle. One conventional vehicle steering assistance system determines a target driving line based on the lane markings (e.g., white lines) on the road the vehicle is traveling on, as recognized by an onboard camera. It then applies steering feedback to the steering wheel so that the steering angle is within an appropriate range for driving the vehicle along the target driving line. This allows the driver to maintain a sense of control over the steering and easily drive the vehicle along the target driving line (see, for example, Patent Documents 1 to 3). Such steering assistance is sometimes called steering guide assistance control or PDA-SA (Proactive Driving Assist - Steering Assist). Japanese Patent Publication No. 2023-163933Japanese Patent Publication No. 2024-88775Japanese Patent Publication No. 2019-209844 The conventional system described above cannot perform steering guidance support control if the lane markings on the left and right sides of the road cannot be recognized by the on-board camera. Therefore, when the vehicle is traveling on a road without lane markings (white lines), such as a race track, steering guidance support control cannot be performed. This invention was made to address the above-mentioned problems. Specifically, one of the objectives of this invention is to provide a steering assistance device, a steering assistance method, and a program for a vehicle that can perform steering guide assistance control even when driving on a circuit. One embodiment of the vehicle steering assistance device of the present invention is: The steering device (10) is applied to a vehicle (HV) equipped with a steering device (10) that applies a basic return torque (TR) to the steering wheel, which is a torque that increases in magnitude as the steering angle, which is the amount of movement of the steering wheel (11), increases, and is a torque that returns the steering wheel to the neutral position. The device comprises a camera sensor (34) that acquires a vehicle front image by photographing the scene in front of the vehicle, an electric motor (21) that generates the torque to be applied to the steering wheel, and a controller (20) that controls the electric motor. The controller is configured to determine a target guide torque (TGtgt) (S645) such that the steering angle (θact) is easily maintained within a predetermined target steering angle range (from θtgt-θc to θtgt+θc) that includes the target steering angle (θtgt), and to generate a torque corresponding to the target guide torque in the electric motor (S625). Furthermore, the controller, If the steering angle is within the target steering angle range, the target guide torque is determined such that the ratio of the increase in torque applied to the steering wheel when the electric motor generates the target guide torque to the increase in the steering angle is greater than the ratio of the increase in torque applied to the steering wheel when the electric motor does not generate the target guide torque to the increase in the steering angle. If the vehicle forward image includes curved section boundaries (C1 to C4), which are road boundaries provided in the curved section of the circuit, the target driving line of the vehicle (T2, T4, T6, T8) is determined using the curved section boundaries included in the vehicle forward image, and the target steering angle (θtgt) is determined based on the determined target driving line. According to this, when a vehicle is traveling on a circuit track without lane markings, the target driving line is determined based on the curve boundaries, and the target steering angle is determined based on that target driving line, thus enabling steering guide support control. In the above description, to aid in understanding the present invention, the names and/or reference numerals used in the embodiments described later are indicated in parentheses for the components of the invention corresponding to those embodiments. However, the components of the present invention are not limited to the embodiments defined by the aforementioned names and/or reference numerals. The present invention also extends to vehicle steering assistance methods and programs thereof. A schematic diagram of a steering assistance device for a vehicle according to an embodiment of the present invention.(A) is a graph showing the relationship between steering angle and basic return torque, and (B) is a graph showing the relationship between steering angle and target assist torque.(A) is a graph showing the relationship between steering angle and target guide torque, and (B) is a graph showing the relationship between steering angle and post-control return torque.A diagram illustrating how to determine the target racing line on a circuit.A diagram illustrating how to determine the target ra