A Compact and Agile Angled-Spoke Wheel-Based Mobile Robot for Uneven and Granular Terrains

Abstract

This study proposes an angled spoke-based wheel(ASW) design to enhance the driving speed of a mobile robot with angled spoke-based wheels called DODO on granular media, asphalt ground, and transitions between them. The design parameters were optimized using the Taguchi method and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$L_9$</tex-math></inline-formula> orthogonal array. The contact method of the feet was selected as a single contact through empirical analysis. Toe in and toe out angles of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$ 15^{\circ }$</tex-math></inline-formula> were applied to the front and rear ASWs. The front and rear ASWs had a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$30^{\circ }$</tex-math></inline-formula> phase difference to minimize the reciprocation of the center of mass along the z-axis. A static analysis of DODO, as well as experimental dynamic analyses were performed. The driving speed of DODO on transitions were verified with the result of staticanalysis.