Robust position control of robotic manipulator in Cartesian coordinates

The authors propose a nonlinear robust control scheme for robotic motion control in Cartesian coordinates. The control input of this scheme consists of nonlinear and linear parts. The nonlinear part decouples and stabilizes robot dynamics in Cartesian coordinates. The linear part utilizes the robust servomechanism theory to suppress effects of modeling error or unknown external disturbance. This scheme was used in the control of a two-joint SCARA-type robot, and simulation results demonstrate that it can achieve fast and precise tracking control in Cartesian coordinates, even in the presence of severe modeling errors