RESEARCH ON SYNCHRONOUS CONTROL STRATEGY OF ROBOT ARM BASED ON CROSS-COUPLING CONTROL

摘要

To reduce the contour errors from the coupling problem between the joints of the manipulators, we propose an integrated strategy combining the virtual spindle into the classical fractional order sliding mode cross-coupling control (FOSMC-CCC) strategy. Firstly, an iterative sliding mode control (ISMC) strategy is proposed to cope with single joint of manipulator, and the stability is proved by Lyapunov function and relative simulation. Secondly, on the basis of the single-joint control, FOSMC-CCC strategy is consequently proposed by using fractional order calculus, sliding mode control (SMC) and cross-coupling control (CCC) structure. Finally, the proposed method is verified by MATLAB/Simulink simulation. The simulation results show that compared with the traditional linear PD cross-coupling control (linear PD-CCC) strategy, the adjustment time is reduced by 0.14s, 0.42 s and 0.35 s, and steady-state error is reduced by 0.0002 rad, 0.0004 rad and 0.0003 rad. Compared with nonlinear PD ring-coupling control (nonlinear PD-RCC) strategy, adjustment time is reduced by 0.12 s, 0.20 s and 0.16 s, and steady-state error is reduced by 0.0001 rad, 0.0002 rad and 0.0001 rad. The simulation results show that synchronous control accuracy of FOSMC-CCC strategy is better.