Model-predictive undercarriage control for a pseudo-omnidirectional, wheeled mobile robot

Abstract

A high degree of mobility and flexibility will be a prerequisite for the successful deployment of future service robots. Currently, pseudo-omnidirectional, wheeled mobile robots with independently steered and driven wheels seem to provide a solid compromise between complexity, flexibility and robustness. Yet, such undercarriages are imposed to the risk of actuator fighting and suffer from singular regions within their configuration space. Within this work a model predictive control (MPC) approach is proposed that addresses both, actuator coordination and singularity avoidance. The control problem is treated within the spherical coordinate representation of the system's velocity space. The MPC approach is simulative and experimentally evaluated w.r.t. the undercarriage of the Care-Obot 3 mobile robot and is compared to an earlier developed potential field (PF) based approach.