Robust control of two-link manipulator with disturbance torque and time-varying mass loads

Robot manipulators play important roles in helping people do repetitive dull jobs marvelously, with taking advantage of redundancy and flexibility. Two-link manipulators are one kind of basic manipulators and are applied in industrial and medical fields. In many application scenarios, external disturbances and time-varying mass loads may appear to have negative vibration effects on motion control for manipulators, and control algorithms that can eliminate such effects are urgently required. This paper proposes a novel control approach for accurate control of two-link manipulator with disturbance joint torques and time-variant mass loads. The proposed control algorithm can make the joint angle error to sustain in a limited bound under disturbances. Meanwhile, the proposed control method is able to make the two joints of the manipulator globally converge to zero if disturbances disappear. Simulation results show the efficiency of the proposed control approach for control of the two-link manipulator with disturbance torques and time-varying mass loads, and performance comparisons with other conventional control methods demonstrate its superiority.