Steering and braking cooperative control method of four-wheel independent drive vehicle

Abstract

The invention discloses a steering and braking cooperative control method of a four-wheel independent drive vehicle. The method comprises the steps that when a vehicle is steered, an ideal steering angle is collected, and then an expected vehicle body slip angle, an expected yaw velocity and an expected yaw angle are obtained according to a reference model; a front wheel steering angle, a rear wheel steering angle and a yawing moment are obtained according to the expected vehicle body side slip angle, the expected yawing angular velocity and the expected yawing angle through a sliding mode variable structure control model, and then an actual vehicle body side slip angle, an actual yawing angular velocity and an actual yawing angle of the vehicle are calculated; when the vehicle is braked,errors are controlled based on a BP neural network PID control model, and then steering and braking cooperative control is conducted on the vehicle; when the vehicle is steered and braked, actual andideal vehicle body slip angles, yaw velocity and yaw angle errors, and actual and ideal slip rates are controlled at the same time based on the BP neural network PID control model, and then steering and braking cooperative control is carried out on the vehicle.

Description

Technical field [0001] The invention relates to the technical field of steering and braking coordinated control, in particular to a steering and braking coordinated control method for a four-wheel independent drive vehicle. Background technique [0002] In the face of increasingly tense energy and environmental protection pressures, governments of various countries have successively introduced a large number of policies and measures to encourage the development of various types of new energy vehicles (pure electric vehicles, hybrid vehicles, etc.). Four-wheel independent drive vehicles, also known as in-wheel motor drive vehicles or distributed drive vehicles, are a special pure electric vehicle. Compared with traditional vehicles, it saves a large number of intermediate transmission parts, and uses motors in four hubs as power sources, which has higher transmission efficiency, more compact structure, and more space utilization. In addition, it is equipped with multiple distribu...

AI Technical Summary

Problems solved by technology

[0004] However, the four-wheel independent drive vehicle has too many degrees of freedom, making it an over-coupled, strongly nonlinear system. It is extremely easy for the distributed actuators to interfere with each other and conflict with each other, resulting in a decline in the overall performance of the vehicle.

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