Control of Two-Link Robot Manipulator with Uncertainty Parameter using Self-Tuning Sliding Mode Control

This paper is present about two-link robot manipulator control with uncertainty parameters that affect the performance of the robot manipulator in tracking the target joint angular position. The dynamic model of a two-link robot manipulator is obtained by solving the Lagrange Equation. Sliding Mode Control (SMC) is robust nonlinear control method, but in some uncertainty parameters, the performance of sliding mode control is still not satisfactory enough to track the desired joints angular position. This paper proposed least-square based Self-Tuning mechanism to improve the performance of SMC in tracking the target joints angular position against uncertainty parameter such as mass parameter changes that are caused by activity of robot manipulator when lifting a load. To prove the effectiveness and robustness of the proposed method, the Self-Tuning SMC is compared with the Conventional SMC Signum function and Saturation function. The computer simulation results show that the proposed method is able to bring back to the desired angular position that is shifted about 0.25 radian on θ
₂
and 0.02 radian on θ
₁
without any steady-state error and the chattering phenomenon on torque input when mass parameter is increased 0.15kg on link 2. Meanwhile, in the same conditions, the Conventional SMC is not able to maintain the joints angular position without any steady-state errors and chattering phenomenon is occurs. From the results, it is shown that proposed method is more efficient and robust against the uncertainty parameters.