基于阿克曼原理的4WID/4WIS汽车循迹控制研究

针对四轮独立驱动、独立转向汽车循迹控制精度和转向稳定性兼容问题，同时考虑减小轮胎磨损，延长轮胎使用寿命，本文基于阿克曼转向原理和RBF神经网络PID理论，提出了一种自适应的循迹控制方法.首先，设计了基于RBF神经网络PID理论的自适应转向控制器，用于控制前内轮转角，保证循迹精度；其次，后内轮以减小质心侧偏角为目标进行辅助转向，保证转向稳定性；接着，基于阿克曼转向原理，确定外轮转角，保证各轮侧偏力分配合理；最后，采用同一瞬心法，确定各车轮转速，以减小轮胎滑动率.本文搭建了CarSim和MATLAB/Simulink联合仿真平台，进行了仿真实验，结果表明：本文提出的循迹控制方法，不仅能获得较小的循迹偏差和质心侧偏角，保证了足够的循迹控制精度和转向稳定性，同时还减小了轮胎滑动率，有利于减小轮胎的磨耗.

Research on tracking control of 4 WID/4 WIS vehicle based on aekerman principle

Aiming at compatibility of tracking control accuracy and steering stability of four-wheel independent drive and independent steering vehicles, and considering reducing tire wear and improving tire service life, an adaptive tracking control method is proposed based on Ackerman steering principle and RBF neural network PID theory. Firstly, an adaptive steering controller based on RBF neural network PID theory is designed to control the front inner wheel angle and ensure tracking accuracy. Secondly, the rear inner wheel carries out auxiliary steering with a goal of reducing the sideslip angle of center of mass to ensure steering stability. Then, based on Ackerman steering principle, the outer wheel angle is determined to ensure reasonable distribution of side deflection force of each tire. Finally, the same instantaneous center method is used to determine the spin speed of each wheel to reduce tire slip rate. In this paper, a joint simulation platform of CarSim and MATLAB/Simulink is built and simulation experiments are carried out. The results show that the tracking control method proposed in this paper can not only obtain small tracking deviation and centroid sideslip angle, which ensure sufficient tracking control accuracy and steering stability, but also reduce tire slip rate, which is conducive to reducing the tire wear.