Second order sliding mode control method for autonomous vehicle based on visual dynamics

Abstract

The invention discloses a second order sliding mode control method for an autonomous vehicle based on visual dynamics, and belongs to the field of intelligent vehicles. The method includes the steps that firstly, a two-freedom vehicle lateral dynamic model and a visual dynamic model are established and combined, and a curvature of rho of a desired path on a preview point is taken as the input of external disturbance, and a vehicle dynamic model is reconstituted; and according to an actual offset distance of y<L> between a front viewpoint of vehicle heading and the desired path and an actual tangential angle of epsilon<L> between the vehicle heading and the desired path, a control law of a first order sliding mode controller is designed; based on the control law of the first order sliding mode controller, by reconstructing a sliding mode variable of s, a value range of weighting coefficients of lambada and alpha in a control law u<s> of a second order sliding mode controller of super-twisting is obtained; the value range of weighting coefficients of lambada and alpha is applied to the control law u<s> of the second order sliding mode controller to achieve automatic driving of vehicles. According to the second order sliding mode control method for the autonomous vehicle based on the visual dynamics, a series of problems such as nonsequence of traditional sliding mode control andchattering in a nonlinear system control theory are solved, and strong robustness is achieved.

Description

technical field [0001] The invention relates to a second-order sliding mode control method for an automatic driving vehicle based on visual dynamics, belonging to the field of intelligent vehicles. Background technique [0002] With the development and progress of society, more and more people pay attention to smart vehicles. Because of their potential value and application prospects in the future, various researches on smart vehicles are also going on. At the same time, the application of emerging technologies such as lidar, computer vision, and GPS in the field of intelligent vehicles has prompted research on intelligent vehicle control strategies based on path perception. [0003] Path perception is to use the existing sensor technology to perceive and plan the path of the vehicle in advance, generate a desired path for the vehicle, and then input the parameters of the path into the vehicle controller. Control the driving speed to complete the tracking of the desired pat...

AI Technical Summary

Problems solved by technology

However, the above-mentioned existing literature has the following shortcomings: the traditional linear control strategy cannot cope well with real-time changing driving conditions; and it does not have good robustness; the first-order sliding mode control will produce strong Chattering; at the same time, continuous control cannot be produced in changing conditions

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