Balancing Unicycle Travelling on an Inclined Surface

Document Type : Original Article


Electrical & Electronic Engineering Department, Shahed University, Tehran, Iran


A self-balancing unicycle robot is equipped with roll stabilizing unit and a wheel which is in charge of simultaneous unicycle frame upright holding and path tracking. Linear quadratic regulators (LQR) are designed for the roll, pitch and path tracking to make the vehicle successfully perform its desired operations. Even though control loops in general and LQR in specific subdue disturbances such as road slope, still some extra strong measures may be required. The road tilt alters the device dynamic and exerts forces influencing its behavior against reference commands. In this respect, gain scheduling LQR is designed and its impact on the system performance with regard to the conventionally designed LQR is discussed. Simulation results are used to validate the propositions. 



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