Omni Differential Drive for Simultaneous Reconfiguration and Omnidirectional Mobility of Wheeled Robots
Ziqi Zhao, Peijia Xie, Max Q. -H. Meng
TL;DR
ODD addresses the challenge of achieving passability, agility, and stability for wheeled robots operating in human environments. It introduces a lateral differential drive with variable wheel spacing $d$, enabling simultaneous reconfiguration and omnidirectional mobility without extra actuators. The authors develop kinematic and dynamic models, implement a collinear Mecanum-wheel prototype, and apply a parallel cascade PID control framework, with experimental validation of mobility, reconfiguration, and passability. This drive technology promises flexible footprint adaptation and enhanced navigation for service and wheeled robotic platforms.
Abstract
Wheeled robots are highly efficient in human living environments. However, conventional wheeled designs, limited by degrees of freedom, struggle to meet varying footprint needs and achieve omnidirectional mobility. This paper proposes a novel robot drive model inspired by human movements, termed as the Omni Differential Drive (ODD). The ODD model innovatively utilizes a lateral differential drive to adjust wheel spacing without adding additional actuators to the existing omnidirectional drive. This approach enables wheeled robots to achieve both simultaneous reconfiguration and omnidirectional mobility. Additionally, a prototype was developed to validate the ODD, followed by kinematic analysis. Control systems for self-balancing and motion were designed and implemented. Experimental validations confirmed the feasibility of the ODD mechanism and the effectiveness of the control strategies. The results underline the potential of this innovative drive system to enhance the mobility and adaptability of robotic platforms.