关键词: 并联机械臂, 滑模控制, 新型趋近律, RBF网络

Abstract: Aiming at the problems of the uncertain dynamic and load fluctuations impact on the control performance of parallel robotic arm,time-varying term and variable loads in the dynamic model were considered as total disturbance,and a sliding mode control method was proposed. In order to improve the performance of sliding mode control algorithm,a new reaching law consisting of fast reaching term and slow reaching term was proposed,and the accessibility condition and convergence time were discussed. Besides,the Radial Basis Function (RBF) network was used to estimate the total disturbance. To estimate the total disturbance and suppress perturbation of controller parameters,adaptive laws were designed for the parameters of RBF network and controller. Based on the proposed new reaching law and the disturbance obtained by the RBF network,the sliding mode controller was designed and the control stability was proved. Finally,the adaptive sliding mode control method based on the new reaching law and RBF network was proposed. Simulation results show that the proposed control method has strong anti-interference performance and fast response,reducing the convergence time by 1/3 compared to traditional reaching law controller,and greatly reduced the controller jitter.

Key words: parallel robotic arm, sliding mode control, new reaching law, RBF network