Model-based Control for 6-DOF Parallel Manipulator

A novel model-based controller for six-degree-of-freedom (DOF) parallel manipulator is proposed in this paper, in order to abatement the influence of platform load variety and compel the steady state errors converge to zero. In this paper, 6-DOF parallel manipulator is described as multi-rigid-body systems, the mathematical model of the 6-DOF parallel manipulator including dynamics based on Kane method and kinematics used closed-form solutions and Newton-Raphson method is built in generalized coordinate system. The model-based controller is presented with the feedback of cylinders positions of platform, desired trajectories and dynamics gravity as the input and the servovalve current as its output. The performance of the control scheme for 6-DOF parallel manipulator is analyzed. Simulation of the parallel manipulator with model-based controller is executed in MATLAB/Simulink, the simulation results indicate the model-based controller can reduce the influence of load variety of platform and eliminate steady state error of 6-DOF hydraulic driven parallel manipulator.