  Wheeled robots are highly efficient in human living environments. However,
conventional wheeled designs, with their limited degrees of freedom and
constraints in robot configuration, struggle to simultaneously achieve
stability, passability, and agility due to varying footprint needs. 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. To
validate the feasibility of the ODD model, a functional prototype was
developed, followed by comprehensive kinematic analyses. Control systems for
self-balancing and motion control 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.
