PSO-PID-Based Optimization and HIL Verification Method for the Rear-Mounted Linkage Adjustment of Hilly-Mountainous Tractors

For the rear-mounted linkage adjustment system using traditional PID control, it is difficult to determine the optimal PID parameters, which leads to the problems of excessive overshoot, slow adjustment speed, insufficient precision and poor tracking performance in implements attitude adjustment. In this paper, a rear-mounted linkage device with independent control of dual hydraulic cylinders is designed, and an optimization method for rear suspension adjustment based on Particle Swarm Optimization (PSO) algorithm to optimize the PID parameters is proposed. A simulation model of the rear-mounted linkage adjustment system was constructed, and MATLAB/Simulink simulation comparison tests and Hardware-in-the-Loop validation tests were conducted. The results show that compared to traditional PID control, the PSO-PID controller reduces the response time by 28.52% in tracking the target tilt angle, decreases the overshoot by 43.87%, and significantly improves the dynamic characteristics of the system. This verifies the effectiveness of the optimization method proposed in this paper, which is of great significance and value for improving the operational efficiency of hilly and mountainous tractors, reducing energy consumption, and protecting soil ecology.