Lateral Transfer Assist Robot (LTAR): Development of a proof-of-concept prototype

BACKGROUND: Falls during transfer to and from a wheelchair are associated with numerous problems. Factors responsible for difficulty in transferring include horizontal/vertical gaps between surfaces; obstacles, such as armrests; and complicated brake/footrests configurations before transferring. Moreover, controlling a wheelchair sufficiently close to the transfer surface within the confined home space is difficult. OBJECTIVE: We described the design of the novel Lateral Transfer Assist Robot (LTAR) for solving problems during transfer. Furthermore, the effectiveness and usability of the robot were preliminary examined in healthy adults. METHOD: The transfer problems and basic designs were organized. The effectiveness of the prototype was measured by three-dimensional motion analysis and questionnaire. RESULTS: The prototype LTAR was developed. With just a push on a button, the footplate lowers to the floor and the seat and armrest lowers to the height of the seating surface to fill the gap between the surfaces. Using these features, users can transfer by simply shifting their buttocks sideways. Additionally, LTAR has omnidirectional wheels that help move it within a narrow space. The LTAR was confirmed to reduce the physical and subjective burden, except for maneuverability. CONCLUSION: The LTAR was found to be effective for home use and reducing burden of transfer.