Usability Study of a Powered Lift for Wheelchair Users

Abstract

Stairways into building or public vehicles are important environmental barriers that limit accessibility to users of wheeled mobility devices. Powered van lifts can serve as an alternative to stairs, ramps or porch lifts, but they have not yet been carefully evaluated for this purpose. The objectives of this study were to characterize the usability of a powered van lift device for wheelchair users and demonstrate the utility of using a multi-method evaluation approach to identify opportunities for design improvements. Twenty experienced wheeled mobility device users either alone (n=11) or with the assistance of a caregiver (n=9) completed tasks using a powered van lift. Measurements were made on the unrestricted space required to enter and exit the lift, time required to enter and exit the lift, errors made during the operation of the lift's control, and self-reports of device usability obtained with a questionnaire. Results indicated that the clear space required for the lift was less than what would be expected for a ramp and that the self-reported usability of the device was reasonably good. However, the time required to use the lift was high and participants had difficulty operating the lift's safety-belt. Improvements should be made to the design of the safety-belt to increase usability. Additional studies that include other user populations are recommended to investigate the efficacy of the device as an alternative to stairs, ramps and “porch” lifts.