This paper presents a novel approach to inverted pendulum control and unstable equilibrium angle (UEA) estimation through a proposed velocity suppression mechanism implemented in a single code. The key innovation lies in achieving control using solely an integral controller whose parameters satisfy a specific velocity suppression condition. Traditional inverted pendulum systems face a fundamental challenge: the arduous task of finding optimal proportional–differential–integral parameters, complicated by the system’s inherent sensitivity to minor physical variations (such as pendulum weight, length, distortion, and cart-rail friction). Our solution introduces a streamlined integral controller that includes the pendulum’s position, velocity parameters (θ, dotθ), achieving stabilization through the proposed mechanism. This same mechanism is effectively utilized for UEA estimation. The effectiveness was demonstrated on an unknown layout, weight, and moment pendulum inversion with unknown friction or deteriorated effect of 12-years-old device. This work signals a paradigm shift away from complex, model-dependent approaches to more practical, adaptive solutions.

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