Experimental study of the human factors when riding an automated wheelchair: Supervision and acceptability of the automated system

This study investigated the effects of supervision on autonomous wheelchairs, which are considered to be a means of future transportation. A rider using an automated wheelchair needs to be vigilant about the failure modes of the system. This study focused on the effects of human factors on an automated system. Several experiments were conducted in public areas to investigate the influence of human factors including acceptability, capability, and usability on the supervision of an automated system by using questionnaires. The average reaction time from the occurrence of system failure until the emergency switch is activated was found to be similar in all the experiments for all test tracks. Regarding the positions of the subject's hand, several patterns for pushing the emergency switch were observed. The method of supervision for pushing the emergency switch was the same among all subjects, even though they had different attitudes. Most subjects had favourable opinions on the automated wheelchair, whereas some found the supervision bothersome. The results reveal the conditions under which future users would prefer to use the automated wheelchair, given the expected cost and functions. The real-world experimental data are valuable for developing automated wheelchairs and effective human–machine interfaces on automated systems.