Control system of self-leveling in hilly tractor body through simulation and experiment

It is a difficult task to maintain level when hilly tractor is working under complex conditions. In order to solve this problem, a new self-leveling system of tractor body based on a four-point leveling structure was proposed. The PID fuzzy control algorithm was applied in the control system to simulate the performance of new self-leveling system in order to improve the leveling accuracy and stability. The change curves between attitude angles of the tractor body and displacement, velocity, flow of the front and rear wheels were analyzed through AMEsim/Simlink co-simulation. Results show that the tractor body attitude angle is within 5? in the leveling process, which can returning to 0? after leveling, indicating the stability of the leveling system. After the verification of the leveling mechanism, leveling test and simulation of the self-leveling bench were carried out. Comparing results between test and simulation shows that the maximum error and the average error of displacement are 14.23% and 5%, and the maximum error and average error of velocity are 15% and 5%, which verify the accuracy and good performance of the self-leveling system and the control algorithm. This work may provide reference for the design of tractor body leveling system. © 2019, Editorial Board of Jilin University. All right reserved.