新型磨机换衬板机械手的非线性控制系统设计

Design of Nonlinear Control System for a New Relining Manipulator on Ball Mill

链式机械手是具有动态特性显著、非线性和强耦合的复杂系统。针对磨机换衬板机械手的传统线性控制各关节跟踪精度低的问题,设计一种基于双速率计算力矩法的非线性系统控制器。首先,通过SolidWorks软件建立新型磨机换衬板机械手的三维模型;其次,采用牛顿—欧拉法建立链式机械手连杆动力学方程;最后,设计机械手的线性和非线性控制器,并使用Matlab/Simulink仿真软件建立控制框图,进行仿真对比分析。MATLAB仿真结果表明:双速率计算力矩法的非线性控制对比传统的平均重力补偿PD线性控制,其机械手各关节轨迹跟踪精度提高了近5倍,且稳态误差远低于1%,从而验证了基于双速率计算力矩法控制的高效性。

Chain manipu lator is a dynamic,nonlinear and coupled system. Based on the conventional linear controller of relining manipulator on ball mill has low tracking precision,the nonlinear controller is designed by the dual-rate computedtorque method. Firstly,the 3D model of relining manipulator on ball mill was built by SolidWorks;Secondly,the chain manipulator’s dynamics equation was presented by Newton-Euler method;At last,the linear and nonlinear controllers of manipulator were established,and the simulation models were built by Matlab/Simulink to compare and analyze them. The simulation results indicate that the trajectory tracking accuracy of each joint of the nonlinear controller nearly five times higher than the linear controller,and the steady-state error is much lower than 1%. Furthermore,the efficient method is validated by the dual-rate computed-torque.