Thi-Ai-Van Nguyen, Dinh-Hau Vu, Ha-Gia-Huy Nguyen, Nguyen-Chi-Nghia Pham, Khanh-Hoang Cao, Thanh-An Vo, Hong-Long Le, Minh-Tam Nguyen *
Ho Chi Minh City University of Technology and Education (HCMUTE)
01, Vo Van Ngan Str, Thu Duc city, Ho Chi Minh City, Vietnam
* Corresponding author. E-mail: tamnm@hcmute.edu.vn
Robotica & Management, Vol. 29, No. 2, pp. 16-25
DOI: https://doi.org/10.24193/rm.2024.2.3
Abstract: This study explores the use of Linear Quadratic Regulator (LQR) control to stabilize a unicycle robot, a key example within the unicycle-type mobile robot category. Despite its inherent instability, the unicycle robot offers notable advantages over multi-wheeled, statically stable designs, including reduced spatial requirements due to its single ground contact point. The system is modeled using two axes: the roll axis, represented as an inverted pendulum managed by the wheel, and the pitch axis, modeled as a reaction wheel inverted pendulum controlled by a reaction disk. LQR is recognized as an effective approach for controller design in nonlinear systems. This research focuses on designing, implementing, and evaluating LQR controllers with varying weighting matrices to analyze their influence on system performance. Comparative case studies are conducted by altering the weighting matrices and benchmarking the results against the initial configuration. Experimental outcomes highlight the potential of LQR control for achieving robust stabilization of unicycle robots.
Keywords: unicycle robot, velocity control, LQR control, speed control.
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