Issues in controllability and motion planning for overconstrained wheeled vehicles

摘要

Conventional nonholonomic motion planning and control theories do not directly apply to "overconstrained vehicles," such as the Sojourner vehicle of the Mars Pathfinder mission. This paper investigates some basic issues that are necessary to build a motion planning and control framework for this potentially important class of mobile robots. A power dissipation approach is used to model the governing equations of overconstrained vehicles that move quasi-statically. These equations are shown to be switched hybrid systems. Standard notions, such as the Lie bracket, are extended to these switched systems. We then develop a controllability test for such systems. We explore motion planning primitives in the context of simplified examples. 1 Introduction and Motivation Most mobile robots use wheels since they provide one of the simplest means for mobility. Wheels impose nonholonomic constraints on a vehicle's motion, and thus the subject of control and motion planning for nonholonomic wheel...