基于改进PID控制的并联机械臂运动轨迹跟踪仿真

Simulation of Parallel Manipulator Trajectory Tracking based on Improved PID Control

为了提高并联机械臂运动轨迹的定位精度,采用粒子群算法优化PID控制器参数。构建了并联机械臂机构简图模型,通过平面坐标系推导机械臂运动角位移方程式。分析了传统PID控制器模式,给出系统输出误差的适应度函数。对优化后的跟踪效果进行仿真。并与传统PID控制器跟踪效果进行对比。仿真结果表明:无外界干扰,两种控制方法角位移跟踪误差相差不大;有外界干扰,改进PID控制器明显优于PID控制器。说明采用改进PID控制器控制机械臂运动角位移,能够很好的抑制外界环境的干扰,保持系统的稳定输出,提高机械臂角位移运动精度。

In order to improve the positioning accuracy of the parallel manipulator, particle swarm algorithm（PSO） was adopted to optimize the PID controller parameters. A schematic model of parallel manipulator was constructed and the angular displacement equation of the manipulator was deduced by plane coordinate. The traditional PID controller mode was analyzed, and the fitness function of output error of the system was given. Particle swarm optimizationis used to optimize the parameters of PID controller and simulate the optimized tracking effect. At the same time, the tracking effect of traditional PID controller was compared. The simulation results showed that there was no difference in the angular displacement error of the two control methods without external interference, and the improved PID controller was obviously superior to the PID controller with external interference. The improved PID controller was used to control the motion angle displacement of the manipulator, which could effectively suppress the disturbance of the external environment, maintain the stable output of the system and improve the angular displacement motion precision of the manipulator.