Design of the fractional-order adaptive nonsingular terminal sliding mode controller for 6-DOF robotic manipulator

This paper proposes an adaptive nonsingular terminal sliding mode control, for the trajectory tracking of 6 degree of freedom (DOF) manipulator. This method introduces a reaching law with fractional order sign function to guarantee the existence of the sliding motion in finite time. Moreover, the adaptive law is used to deal with modeling errors and external disturbances, which can improve the robustness of system. The singularity problem is eliminated and tracking error converges to zero in finite time. Simulation results show the effectiveness of the proposed control method.