US-12617396-B2 - Driving control apparatus for vehicle

US12617396B2US 12617396 B2US12617396 B2US 12617396B2US-12617396-B2

Abstract

A driving control apparatus for a vehicle includes a surrounding environment recognition device, a brake control device, a drive force control device, and a control unit. The surrounding environment recognition device obtains surrounding environment information of the vehicle. The brake control device performs brake control for the vehicle. The drive force control device performs drive control of front wheels and rear wheels individually. The control unit at least includes a rough road area entry determiner which executes a determination of entry of the vehicle into a rough road area and a road surface μ estimator which estimates a friction coefficient of a wheel contact surface. The control unit executes first avoidance control and then second avoidance control when the vehicle is found to enter an area where it is likely to be stuck in the rough road area based on a determination result of the rough road area entry determiner.

Inventors

Harunobu Horiguchi

Assignees

Subaru Corporation

Dates

Publication Date: 20260505
Application Date: 20240715
Priority Date: 20230906

Claims (10)

1 . A driving control apparatus for a vehicle, the driving control apparatus comprising: a surrounding environment recognition device configured to obtain surrounding environment information of the vehicle; a brake control device configured to perform brake control for the vehicle; a drive force control device configured to perform drive control of front wheels and rear wheels individually; one or more processors; and one or more memories storing instructions causing the one or more processors to: execute a determination of entry of the vehicle into a rough road area, estimate a friction coefficient of a wheel contact surface of the vehicle, execute first avoidance control and then to execute second avoidance control when the one or more processors have determined that the vehicle is to enter an area where the vehicle is likely to be stuck in the rough road area, the first avoidance control causing the vehicle to decelerate and the second avoidance control causing the vehicle to move backward.
2 . The driving control apparatus according to claim 1 , wherein: the first avoidance control is the brake control performed by the brake control device; and the second avoidance control is the drive control performed by the drive force control device.
3 . The driving control apparatus according to claim 1 , further comprising a notifying device, wherein the one or more processors are further configured to: perform a detection of a brake operation performed by a driver who is driving the vehicle, provide an alarm notification using the notifying device; and execute the second avoidance control when the one or more processors have determined that (i) the vehicle is to enter the area where the vehicle is likely to be stuck in the rough road area, and (ii) the brake operation performed by the driver is detected.
4 . The driving control apparatus according to claim 1 , wherein: the first avoidance control is an automatic deceleration control to cause the vehicle to decelerate or stop before entering the area where the vehicle is likely to be stuck.
5 . The driving control apparatus according to claim 1 , wherein: the second avoidance control is reverse driving control to cause the vehicle to move backward away from the area where the vehicle is likely to be stuck.
6 . A driving control apparatus for a vehicle, the driving control apparatus comprising circuitry configured to obtain surrounding environment information of the vehicle, perform brake control for the vehicle, perform drive control of front wheels and rear wheels individually, execute a determination of entry of the vehicle into a rough road area, estimate a friction coefficient of a wheel contact surface, and execute first avoidance control and then to execute second avoidance control when it is determined that the vehicle is to enter an area where the vehicle is likely to be stuck in the rough road area, based on a result of the determination regarding the entry of the vehicle into the rough road area, the first avoidance control causing the vehicle to decelerate and the second avoidance control causing the vehicle to move backward.
7 . The driving control apparatus according to claim 6 , wherein: the first avoidance control is the brake control performed by the circuitry; and the second avoidance control is the drive control performed by the circuitry.
8 . The driving control apparatus according to claim 6 , further comprising a notifying device, wherein the circuitry is further configured to: perform a detection of a brake operation performed by a driver who is driving the vehicle, provide an alarm notification using the notifying device; and execute the second avoidance control when it is determined that (i) the vehicle is to enter the area where the vehicle is likely to be stuck in the rough road area, and (ii) the brake operation performed by the driver is detected.
9 . The driving control apparatus according to claim 6 , wherein: the first avoidance control is an automatic deceleration control to cause the vehicle to decelerate or stop before entering the area where the vehicle is likely to be stuck.
10 . The driving control apparatus according to claim 6 , wherein: the second avoidance control is reverse driving control to cause the vehicle to move backward away from the area where the vehicle is likely to be stuck.

Description

CROSS-REFERENCE TO RELATED APPLICATION The present application claims priority from Japanese Patent Application No. 2023-144517 filed on Sep. 6, 2023, the entire contents of which are hereby incorporated by reference. BACKGROUND The disclosure relates to a driving control apparatus for a vehicle, such as an automobile, which can perform driving control to allow the vehicle to avoid being caught in water or being stuck when driving in a rough road area, for example. Hitherto, as vehicles such as automobiles, for example, as regular four-wheel automobiles, vehicles using an all-wheel drive system for driving all the wheels (usually four) including the front wheels and the rear wheels have been put into practical use and are widespread. Typically, this type of vehicle using the all-wheel drive system has a high rough road running performance and is thus expected to be widely used in various driving environments. For example, when a vehicle drives in an unpaved road, which is regarded as a rough road, or a land which is not subjected to land leveling (hereinafter called an unleveled land), it may enter an area with a puddle, mud, or snow, for example. In this case, the vehicle may be caught in water and become unable to drive, or the driving wheels may spin out, that is, the vehicle may be stuck. In this environment, when the vehicle is likely to be stuck, such as when the front wheels are caught in mud, if the vehicle is the one using the all-wheel drive system, it may get out of the mud by using a drive force applied to the rear wheels. In this case, however, if a drive force is excessively applied to the front wheels, the front wheels may spin out and the vehicle may be caught into an even deeper level. To address this issue, various technologies have been proposed. For example, Japanese Unexamined Patent Application Publication (JP-A) No. 2009-78592 discloses a driving control apparatus for a vehicle using the all-wheel drive system, which can perform drive control to allow the vehicle to get out of such a stuck state by switching a drive force at a suitable timing. SUMMARY An aspect of the disclosure provides a driving control apparatus for a vehicle. The driving control apparatus includes a surrounding environment recognition device, a brake control device, a drive force control device, and a control unit. The surrounding environment recognition device is configured to obtain surrounding environment information of the vehicle. The brake control device is configured to perform brake control for the vehicle. The drive force control device is configured to perform drive control of front wheels and rear wheels individually. The control unit at least includes a rough road area entry determiner and a road surface μ estimator. The rough road area entry determiner is configured to execute a determination of entry of the vehicle into a rough road area. The road surface μ estimator is configured to estimate a friction coefficient of a wheel contact surface of the vehicle. The control unit is configured to execute first avoidance control and then to execute second avoidance control when the control unit has determined, based on a result of the determination of the rough road area entry determiner, that the vehicle is to enter an area where the vehicle is likely to be stuck in the rough road area. An aspect of the disclosure provides a driving control apparatus for a vehicle. The driving control apparatus includes circuitry. The circuitry is configured to obtain surrounding environment information of the vehicle. The circuitry is configured to perform brake control for the vehicle. The circuitry is configured to perform drive control of front wheels and rear wheels individually. The circuitry is configured to execute a determination of entry of the vehicle into a rough road area. The circuitry is configured to estimate a friction coefficient of a wheel contact surface of the vehicle. The circuitry is configured to execute first avoidance control and then to execute second avoidance control when it is determined that the vehicle is to enter an area where the vehicle is likely to be stuck in the rough road area, based on a result of the determination regarding the entry of the vehicle into a rough road area. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate an embodiment and, together with the specification, serve to describe the principles of the disclosure. FIG. 1 is a block diagram illustrating the schematic configuration of a driving control apparatus for a vehicle according to an embodiment of the disclosure; FIG. 2 is a schematic view for explaining a depth limit value of a vehicle driving on a flooded flat road; FIG. 3 illustrates a situation where a vehicle is entering an area where it is likely to be stuck while driving on a flat road; FIG. 4 i