Development of Autonomous Wheelchair for Indoor and Outdoor Traveling

Abstract

In order to assist elderly people and disabled people, this paper describes development of autonomous wheelchair to travel in indoor and outdoor environments for providing traveling ability to any where. For this aim, the autonomous wheelchairs should have traveling-capability without choosing indoor and outdoor environments. Position detection is a key technology for autonomous driving since people decides a traveling direction from a current position and a destination. GPS is a fundamental technology for position detection. However GPS is not available in indoor cases, and GPS is not always available in outdoor cases when tall buildings occlude satellites. In these cases autonomous wheelchair has to detect a self-position by other sensor systems. In this study we have adopted a localization system utilizing 3D maps and a 3D laser range finder. By the 3D localization system our wheelchair system can detect a self-position robustly if the wheelchair is surrounded by obstacles such as pedestrians. To avoid collision our wheelchair system uses short and long term planning. The short planning finds a safe motion-pattern from every conceivable pattern by the simulation on a map. The long term planning generates a feasible route to destination. If the route generated by the long-term planner collides to some obstacles our wheelchair avoids collision by the short term planning. By the localization system and the planning system our wheelchair could operate in public spaces.