Comparison Of Sliding Mode Controller And State Feedback Controller Having Linear Quadratic Regulator (Lqr) On A Two-Wheel Inverted Pendulum Robot: Design And Experiments

Abstract

The current paper investigates two control methods for stabilizing a two-wheel inverted pendulum (TWIP) robot. It is well-known that the controller in the mobile robot plays a critical role in self-balancing and stabilizing. The TWIP robot has two DC gear motors with a high-resolution encoder and zero backlash, but with friction. It is a highly nonlinear and unstable system, which poses challenges for controller design. In this paper, a mathematical dynamic model is built using Lagrangian function method. Furthermore, a sliding mode controller (SMC) is proposed for auto-balancing and yaw rotation. A comparison of the proposed SMC controller and linear quadratic regulator (LQR) has been conducted. The experimental test results demonstrate the SMC controller outperforms (LQR) in terms of transient performance and disturbance rejection ability.