State variable full-constraint direct yawing moment control algorithm based on pavement adhesion coefficient

Abstract

The invention discloses a state variable full-constraint direct yawing moment control algorithm based on a pavement adhesion coefficient, and the algorithm introduces the concept of a barrier Lyapunov function (BLF) into the design of a direct yawing moment controller. In the design process of the controller, safety constraint boundaries of two state variables of a side slip angle and a yaw velocity brought by a pavement adhesion coefficient are considered, and the side slip angle and the yaw velocity are constrained at the same time based on the pavement adhesion coefficient. Therefore, it is fundamentally guaranteed that the side slip angle and the yaw velocity do not violate constraint conditions in tracking control, the unstable working conditions of drifting, transverse drifting and the like caused by the too large side slip angle and the too large yaw velocity of the automobile under the limit working condition are fundamentally avoided, and the transverse stability of the automobile in the running process is improved. Meanwhile, the direct yawing moment full-state constraint controller has shorter tracking convergence time under the condition that constraint conditions are not violated, and the possibility of dangerous working conditions is reduced.

Description

technical field [0001] The invention relates to the field of automobile steering control, in particular to a direct yaw moment control algorithm based on the full constraints of the road surface adhesion coefficient on the side slip angle of the center of mass and the yaw angular velocity. Background technique [0002] During the sharp turn of the vehicle, the vehicle will produce changes in the center of mass side slip angle and yaw rate. When the vehicle speed is too fast, the center of mass side slip angle and yaw rate of the vehicle will increase sharply, which may exceed the safety range of the center of mass side slip angle based on the road surface adhesion coefficient [-tan -1 (0.02μg),tan -1 (0.02μg)] and yaw rate safety constraint range [-μg / u x ,μg / u x ](μ is road adhesion coefficient, g is gravitational acceleration, u x is the longitudinal speed of the vehicle). If the side slip angle of the center of mass is too large, the wheels will slip, the vehicle wil...

AI Technical Summary

Problems solved by technology

Although these stability control methods focus on improving the response characteristics and robustness of the optimal value tracking, they ignore the fact that there is a certain range of safety constraints on the side slip angle and yaw rate, or they only regard the stability boundary as a threshold warning , reach or exceed the upper and lower bounds to call back, it cannot ensure that the state quantity is always within the safe range

This situation will lead to a decrease in the lateral stability of the vehicle, and in severe cases, it will lead to dangerous situations such as vehicle body instability.

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