Autonomous Vehicle Modeling and Velocity Control Based on Decomposed Fuzzy PID

A longitudinal dynamic model of autonomous vehicle is presented. Based on the dynamics analysis, the engine model, hydraulic variator model, automatic transmission model, and vehicle quality model are built to get the transmission relationship from throttle opening degree to vehicle acceleration. The accuracy and the rationality of this dynamic model are verified by CarSim simulation experiments. Fuzzy PID control method is a common intelligent control algorithm. For typical Type-1 Fuzzy sets, fuzzy variable partition and fuzzy rules are a little less fine. In order to improve PID parameter regulation, decomposed fuzzy system (DFS) is introduced to design PID controller. Furthermore, a simplified decomposed fuzzy PID (SDFPID) controller is designed considering the computational complexity. Finally, this paper simulates the performance of PID, fuzzy PID, and SDFPID, respectively. The experiment results show that SDFPID improves the transient response in consideration of the resistance, the vehicle's own transmission efficiency, transmission ratio, engine inertia, and other parameters. The proposed method has good application.