丘陵山地拖拉机坡地自适应控制系统仿真分析与试验

Simulation analysis and experiment of slope adaptive control system of hilly and mountain tractor

针对丘陵山地地形复杂、耕作阻力波动大等问题,基于研制的新型丘陵山地拖拉机及三点悬挂式后悬挂机构,设计坡地自适应控制系统。对位姿调整机构的调整原理进行分析,得出左右悬挂点距车身基准面的距离与地面坡度的函数关系;设计横向位姿调整液压系统,运用AMEsim搭建横向位姿调整系统的液压系统仿真模型,并采用模糊PID控制方法对仿真模型进行控制性能仿真;搭建拖拉机后悬挂系统控制试验平台,进行拖拉机后悬挂横向位姿调整试验。当坡度低于15°,后悬挂机构跟随坡地调整效果良好,具有良好的稳定性。由仿真结果和对比试验可知,二者位姿调整位移最大误差为9.32%、平均误差为4.2%;所开发的坡地自适应控制系统具有较高的控制精度,可为丘陵山地拖拉机坡地自适应问题提供借鉴。

In view of the problems of complex terrain and large tillage resistance fluctuation in hilly and mountainous areas,based on the developed new hilly and mountainous tractor and three‑point suspension rear suspension mechanism,an adaptive slope control system was designed.Firstly,the adjustment principle of the posture adjustment mechanism was analyzed,and the functional relationship between the distance between the left and right suspension points and the reference plane of the car body and the ground slope was obtained.Secondly,the electronic control hydraulic system for lateral position and attitude adjustment was designed.The hydraulic system simulation model of lateral position and attitude adjustment system was built by AMEsim,and the control performance of the simulation model was simulated by fuzzy PID control method.Finally,the control test platform of tractor rear suspension system was built,and the lateral posture adjustment test of tractor rear suspension was carried out.The results showed that the rear suspension mechanism had good adjustment effect and good stability when it followed the slope within 15°.According to the simulation results and comparison test,the maximum error of the pose adjustment displacement was 9.32%and the average error was 4.2%.It was proved that the developed slope adaptive control system had high control accuracy and could provide reference for hill and mountain tractor slope adaptive problem.