Powered wheelchair control based on the dynamical criteria of stability

This paper concerns stability of powered four-wheeled wheelchairs with two driving wheels and two small sized front wheels. The block diagram of the proposed controller includes a special module that analyses user's commands before their execution. Referring to a specific criterion for estimation of the user's commands, this module automatically modifies the commands that could jeopardise wheelchair equilibrium stability. The theoretical base for the synthesized algorithms is presented. The paper presents some ideas, represented with block diagrams that affect the practical realization of the proposed approach. (C) 2002 Elsevier Science Ltd. All rights reserved.