模糊PID控制在万向电动底盘上的应用

Application of Fuzzy-PID Controller in Electic Chassis Featured by Mecanum Wheel

为满足车辆在狭小封闭空间内运行的要求,克服传统的工业车辆及特种车辆底盘在转向、排放和噪声方面的缺点,设计研发出一种基于Mecanum车轮的电动万向底盘。在该电动底盘前期半闭环控制系统的基础上,分析简化运动学模型,设计出基于参数分配器的模糊PID全闭环控制系统,并确定系统的硬件结构和软件流程。然后对基于该软硬件控制系统的万向底盘进行试验对比分析,分别选取角速度?z=0°/s,速度νx=νy=0.5 m/s的匀速直线运动和角速度?z=25°/s,速度νx=νy=0.5 m/s的匀速圆周运动两种特定工况下,底盘的速度和角速度在控制系统改进前后的实际测试值与期望值的误差对比的试验结果对比分析,通过分析得出相对于只进行电动机编码器半闭环反馈控制系统,改进后的全闭环控制系统具有更好的响应时间和稳态误差精度,更加有利于该万向电动底盘的推广应用。

The traditional industrial vehicles and special purpose vehicles have disadvantages in aspect of steering,emission and noise,which on one hand results to inflexible operation and apparently does not conform to the subject of environment protection on the other.In order to overcome these shortcomings that vehicles can run in a small enclosed space as it is demanded and less environmental damege is caused,the improved control system of electric chassis featured by mecannm wheel is designed and developed.On the basis of earlier control system of the electric chassis,the kinematics models are analiced and simplified,closed-loop control system is designed based on fuzzy proportion intergration differentiation（PID）parameter distributor,and the hardware and software design is completed for control system.Two drive cycles are done to compare the new control system with the earlier control system,one drive cycle is a uniform linear motion which the speed vx=vy=0.35 m/s and angle speed ω2=0 °/s; another drive cycle is a uniform linear motion which the speed vx=vy=0.5 m/s and angle speed ω2=25 °/s; The experimental analysis suggested the improved closed-loop control system responded faster and had more accurate steady-state error in comparison of the motor encoder semi-closed loop feedback control system,which is more conductive to the promotion and application of this electric chassis.