Guaranteeing a Bounded Tracking Error for Angular Position in Servo Systems Control Based on a Robust Sliding-Based Controller

In the angular position control of servo systems, the issue of ensuring the Convergence (CVG) of the Tracking Error (TE) to a small and limited bound, as well as the chattering issue, are two important challenges. This paper addresses this challenge by presenting a new controller from the Sliding Mode Control (SMC) family. In this new controller, a new Reaching Law (RL) is used, in which a function based on the Barrier Function (BF) is used. The issue is that the tracking target, under any initial conditions, eventually converges to a small and limited bound, which is adjusted by the designer. In addition, this RL is robust to Model Uncertainties (MU), providing a robust performance for controlling the position of this machine. The stability of this controller is proven by Lyapunov theory, during which the CVG of the TE to a limited bound is guaranteed. In addition, this controller has the ability to decrease the chattering phenomenon to a good extent. A series of practical tests was conducted in the laboratory to examine the performance of the Proposed Method (PM), and the results confirmed its effectiveness in the above-mentioned field.