Although balancing of inverted pendulum is a well established problem, it continues to present more challenges in modern control designs. While sliding mode control has achieved considerable success in controlling inverted pendulums, most of these advancements have been primarily validated through simulations. Unfortunately, the complexity, and high computational demands of these controllers often limit practical implementation. To address these issues, we constructed a new inverted pendulum system, incorporating a stepper motor to reduce the backlash phenomenon commonly associated with a DC motor, thereby ensuring precise motion control. A simplified sliding mode controller was then designed for the augmented model of inverted pendulum and compared to a linear quadratic controller in practical implementation. The experimental results reveal that the sliding mode control significantly improves the system response, and effectively reduces the steady state errors in pendulum angle and cart position.

In this paper an integral linear quadratic regulator (ILQR) is proposed for balancing the inverted pendulum (IP) system. Dynamic model of the IP system, using the acceleration of the cart as control input is derived. Subsequently, the dynamic model is linearized at operation region to obtain a linear model for the controller design. This model is further enhanced by incorporating an integral term of the cart position to formulate augmented model for the ILQR control. The control input of the ILQR, essential for balancing the IP and keeping the cart at the desired position, is determined by solving the Riccati equation. Simulation and experimental results are presented to evaluate the effectiveness of the proposed control in balancing the IP while successfully reaching the desired cart position.