Vehicle braking stability control method and system

Abstract

The invention discloses a vehicle braking stability control method and system. The method includes the following steps that the actual yaw velocity of a vehicle is acquired; a target yaw velocity of the vehicle is calculated; the difference between the target yaw velocity and the actual yaw velocity and the absolute value of the difference are calculated; according to the absolute value, the braking states of the vehicle are judged, wherein the braking states includes stable braking and instable braking; when the braking state of the vehicle is instable braking, braking instability types of the vehicle are judged according to the difference, wherein the braking instability types include over-steering and insufficient steering; the slip rate of wheels is calculated; according to the brakinginstability type of the vehicle and the slip rate of the wheels, the brake force of the wheels on one side is controlled to be increased or the brake force of the wheels on the other side is controlled to be reduced. According to the method, when the vehicle is instable in the steering braking process, the situation that the brake force is excessively increased, an anti-lock braking system of thevehicle is activated and accordingly braking fails is avoided, and the stability of a vehicle body is greatly improved.

Description

technical field [0001] The invention relates to a vehicle braking stability control method and system. Background technique [0002] At present, the more popular vehicles in the market are equipped with a control method combining ABS (brake stability system) and ESP (steering stability system). Dangerous phenomena such as sideslip and tail flicking during braking can shorten the braking distance; while ESP mainly controls the yaw moment by applying braking force, so that the vehicle not only maintains stability when driving in a straight line, but even maintains the stability of the vehicle body during steering. stability. [0003] However, this technology also has certain limitations. When the brake is applied during the steering process of the vehicle, when the vehicle body becomes unstable, although the ESP function is activated at this time, only the braking force is used to control the yaw moment. Not high, when the tire on the side that needs to apply the brake is br...

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Problems solved by technology

[0003] However, this technology also has certain limitations. When the brake is applied during the steering process of the vehicle, when the vehicle body becomes unstable, although the ESP function is activated at this time, only the braking force is used to control the yaw moment. Not high, when the tire on the side that needs to apply the brake is braking and is at the optimal slip rate, the braking force applied by the ESP will conflict with the ABS function at this time, and the braking force cannot be increased, so that the ESP can increase the braking force by increasing the braking force. The purpose of maintaining the stability of the vehicle body fails

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