The Dynamic Modeling and Analysis for A Redundantly Actuated Omnidirectional Mobile Robot

Abstract

Recently, quite a few applications of omnidirectional mobile robots have been reported. However, understanding of some fundamental issues still remains as further study. One of the issues is the exact dynamic model. Previous studies very often ignore the wheel dynamics of mobile robots and also suffer from algorithmic singularity. Thus, selection of actuator or control algorithms based on the incomplete plant model does not guarantee the control performance of the system. This paper deals with the singularity-free, exact dynamic modeling and analysis of omnidirectional mobile robot having three caster wheels. Initially, the exact dynamic model of the mobile robots including the wheel dynamics is introduced. The joint-space and operational-space dynamic model are derived as analytical forms. Through simulation, the discrepancy of the incomplete dynamic model is shown by comparison with the exact dynamic model. Furthermore, useful aspect of redundant actuation is also discussed.