The Wheelbot: A Jumping Reaction Wheel Unicycle

Abstract

Combining off-the-shelf components with 3D-printing, the Wheelbot is a symmetric reaction wheel unicycle that can jump onto its wheels from any initial position. With non-holonomic and under-actuated dynamics, as well as two coupled unstable degrees of freedom, the Wheelbot provides a challenging platform for nonlinear and data-driven control research. This paper presents the Wheelbot's mechanical and electrical design, its estimation and control algorithms, as well as experiments demonstrating both self-erection and disturbance rejection while balancing.

Erratum: In the initial publication, Equation (3) was wrong and has been corrected in this version. Equation (3) relates to the transform from averaged body rates ${}^{\text{B}}{\omega }_i$ to Euler rates. Importantly, the results in this papers are not affected by the wrong transform. More details are found in the projects github repo: https://github.com/AndReGeist/wheelbot-v2.5