A trajectory tracking control method for intelligent vehicles under extreme conditions

Abstract

The invention discloses an intelligent automobile trajectory tracking control method in a limit working condition and belongs to the technical field of intelligent automobile control. The method includes the steps that firstly, a nonlinear vehicle kinetic model is established, the kinetic model is used for conducting phase trajectory analysis under a vehicle stable steering condition, a vehicle steering stability area is determined, the vehicle steering stability boundary is calculated, and the obtained vehicle steering stability area is used as a security constraint for a trajectory trackingproblem; the nonlinear vehicle kinetic model is linearized, front wheel cornering force serves as input, first-order Taylor expansion is conducted on rear wheel cornering force in the position of a current working point, and a linearized vehicle kinetic equation is obtained; and the linearized vehicle kinetic model serves as a prediction model, the steering stability area serves as the security constraint, the trajectory tracking problem based on a model prediction control method is established, and the problem is solved so that the front wheel cornering force can be obtained. A tire inverse model is used for reserve solution to obtain a front wheel steering angle which serves as final control input. On the premise that the vehicle stability is guaranteed, trajectory tracking of an intelligent automobile is achieved, and instantaneity is good.

Description

technical field [0001] The invention relates to a trajectory tracking control method of an intelligent vehicle under extreme working conditions, and belongs to the technical field of intelligent vehicle control. Background technique [0002] With the continuous development of social economy, automobiles have been greatly popularized, the number of automobiles around the world is gradually increasing, traffic jams are serious, and the occurrence of traffic accidents is showing a rising trend. The problem of road traffic safety has become a global problem, and vicious traffic accidents are one of the important causes of casualties. [0003] In the operation of emergency obstacle avoidance, overtaking and changing lanes, and the driver's wrong steering, the steering stability of the car deteriorates sharply. Traffic accidents, especially in the case of bad weather such as rain and snow, the road surface adhesion coefficient is small, when the tire working point enters the non-...

AI Technical Summary

Problems solved by technology

The nonlinear dynamic model with the front wheel angle as the input is used as the prediction model of MPC. Its advantage is that the accuracy of the model is relatively high. The disadvantage is that the nonlinear dynamic model increases the calculation amount of the controller, which makes the controller design more complicated and difficult to solve. increase, real-time performance is difficult to guarantee

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