Dynamics analysis and control of all-terrains wearable vehicle

Abstract

Transferring humans while carrying loads on all types of terrains efficiently using compact means of transportation is still a challenge. This may be due to the unstructured areas humans need to move through, or due to traffic congestions in structured roads. Some compact-size, light-weight transportation systems have been developed but they provide only a partial solution to the stated problem. This paper presents the dynamics analysis and control of a novel all-terrains wearable vehicle, a new transportation means consisting of a lower extremity exoskeleton carrying two motorized wheels and two free wheels. On flat free ground, this novel system utilizes its wheels to travel fast and when faced with crowded traffic or unstructured area, the human just switches into walking mode. CAD models of the human and the wearable vehicle are developed, and a dynamic human walker is built in MSC ADAMS and is used for proving the feasibility the proposed wearable vehicle in its two modes of operation. PD controller with gravity compensation is designed to ensure that the wearable vehicle is tracking the human motion in the walking mode, and the results obtained show the effectiveness of the controller, the vehicle dynamics are also studied, and the critical acceleration safety margins are defined.