Multivariable Sliding Mode Control Approach via ESO-assistance for tracking tasks of a 3-DoF Robotic Manipulator actuated by PMSMs

Robotic manipulators are nowadays very used machines in manufacturing industry. Therefore, the design and application of suitable control techniques take high relevance in order to obtain desired results in terms of trajectory tracking tasks for robots. This paper initially presents the development of the dynamic model, through the Lagrange method, of a 3-DoF robotic manipulator actuated by permanent magnet synchronous motors. Then, a multivariable sliding mode control approach based on a multivarible high-order Extended-State Observer (ESO) is proposed to address the problem of trajectory tracking tasks. The stability of the proposed approach is analyzed via Lyapunov theory in terms of uncertainties and external disturbances. Finally, the proposed scheme is validated through simulations using three cases: disturbance rejection, and trajectory tracking with/without disturbances. The results show that the proposed scheme is robust and provides high performance in tracking tasks.