A New TimeVarying Feedback RISE Control of PKMs: Theory and Application In this paper, we propose a novel timevarying feedback control strategy based on the Robust Integral of the Sign of the Error (RISE). The main motivation is to enhance the tracking performance of RISE controller at high dynamic operating conditions. RISE control law ensures a semiglobal asymptotic tracking without introducing severe restrictions on the uncertain and nonlinearly parametrized systems. More nonlinearities are added to the original RISE control law by replacing the static feedback gains with nonlinear ones which depend on the system state variables. The proposed contribution is implemented in realtime experiments on a nonredundant threedegreesoffreedom parallel manipulator named Delta. Comparing to the standard RISE controller, experimental results show better tracking performances of the proposed timevarying feedback RISE controller.

Decoupling Control and Simulation of a 3RSR Spheroid Parallel Wrist The control of position and trajectory tracking are critical issues in parallel robots. Traditional PID tracking algorithms, which are based on kinematics control use the position and speed deviation as a negative feedback in order to design a controller. However, this method is not only hard to maintain the excellent dynamic and static quality of a system, but it is also incapable of realizing complete decoupling, and it needs large energy to be controlled. To overcome such drawbacks, this paper proposes, a computed torque decoupling control strategy for a 3RSR spheroid parallel mechanism. The control strategy includes a computed torque decoupling control method with traditional PD controller and selfadaption fuzzy controller. It was proved that the corresponding Lyapunov function is global asymptotic stable in the ideal and nonideal estimation. A set of ADAMSMATLAB dynamic simulations were established based on virtual prototyping technology. The results demonstrated that the performance of the control scheme with selfadaption fuzzy controller is more effective than that with PD controller.