高地隙自走式喷雾机多轮转向系统设计与试验

Design and Experiment of Multifunctional Steering System for High Clearance Self-propelled Sprayer

摘要:

大型高地隙自走式喷雾机在田间作业过程中，由于整车地隙高、质量以及体积较大，导致换行及转场作业困难，影响作业效率。为提高喷雾机的机动性能和作业效率，设计了一套全液压多轮转向系统，并提出了基于PID控制方法的四轮转向系统控制方法。在建立全液压转向系统数学模型的基础上，应用Matlab/Simulink 进行了转向系统仿真分析。仿真结果表明：四轮转向过程中后轮转角对前轮转角的跟随存在0.04s的滞后，最大转角跟随误差为2.82°，误差在阿克曼转向理论允许范围之内，满足转向要求。基于研发的3WPG-3000型大型高地隙自走式喷雾机，搭建了多轮转向系统实车试验平台，进行了后轮对前轮转向角的跟随控制试验，试验结果表明：在田间随机转向试验过程中，最大转角跟随误差为2.60°，满足四轮转向要求，验证了所设计的多轮转向系统的响应性、准确性和稳定性。

Abstract:

During the field operation of high clearance selfpropelled sprayer, due to the high ground clearance, large quality and volume of whole vehicle, leading to difficulties in line changing and transfer operations that affects the efficiency of operation. In order to improve the operating efficiency of the sprayer, a steering mechanism and hydraulic steering system was designed, a control method of four wheel steering system based on PID was also proposed. Based on the mathematical model of the full hydraulic steering system, the simulation analysis of the steering system was carried out by Matlab/Simulink, the simulation result showed that: during the four wheel steering (4WS) process, the rear wheel followed the front wheel with a hysteresis of 0.04s, the maximum angle following error was 2.82°, the error was within the allowable range of Ackermans steering theory which satisfied the steering requirements. Then based on the developed 3WPG-3000 high clearance selfpropelled sprayer, a multiwheel steering system real vehicle test platform was built, and the tracking control test of the rear wheel to the front wheel angle was carried out，the result showed that during the random steering test in the field, the maximum angle following error was 2.60°, meeting the requirements of 4WS, verification of the responsiveness, accuracy and stability of the designed multiwheel steering system. The research results provided a theoretical basis for the development of multiwheel steering system of high clearance selfpropelled sprayer.