Fuzzy algorithm based obstacle avoidance control of electric powered wheelchair using ultrasonic sensor

This paper describes a novel obstacle avoidance control scheme of electric powered wheelchairs for realizing the safe driving in various environments. ¿Electric powered wheelchair¿ which generates the driving force by electric motors is expected to be widely used as a mobility support system for elderly people and disabled people, however, the driving performance must be further improved because the number of driving accidents caused by elderly operator´s narrow sight and joystick operation errors is increasing. This paper proposes a novel obstacle avoidance control scheme based on fuzzy algorithm to prevent driving accidents. The proposed control system determines the driving direction by fuzzy algorithm based on the information of the joystick operation and distance to obstacles measured by ultrasonic sensors and the driving risk by fuzzy algorithm based on the information of the gap between the user´s intent and the driving direction and the velocity of electric powered wheelchairs. Fuzzy rules to determine the driving direction and risk are designed surely to avoid passers-by and walls considering the human´s intent and driving environments. Some driving experiments on the practical situations show the effectiveness of the proposed control system.