Fuzzy-sliding mode control for flexible-joint manipulator based on friction compensation

For overcoming unknown external disturbance, the nonlinearity and uncertainty of the flexible joint manipulator, a novel robust controller is proposed based on fuzzy-sliding mode control and friction compensation. The fiction compensation based on model can effectively predict the friction amplitude and compensate the dynamic error. The external uncertain disturbance, nonlinear part of friction, parameters variation, modeling error and so on can be overcome by the fuzzy-sliding mode control. Experimental results on the platform of HIT four degrees of freedom flexible joint manipulator show that the proposed controller not only can realize good position tracking performance, independency to parameters fluctuation, but also have a strong anti-interference ability.