Volunteer Evaluation of AWTORS

Sponsor: Toyota Collaborative Safety Research Center

Dates: June 2020 to October 2021

Researchers: Kathleen D. Klinich, Nichol R. Orton, Laura Malik, Ellison Zak, Miranda St. Amour, Miriam A. Manary

This project evaluated an automated wheelchair tiedown and restraint system (AWTORS), developed as part of a study sponsored by the National Highway Traffic Safety Administration (NHTSA), that could be safely and independently used in an automated vehicle (AV) by someone using a wheelchair as vehicle seating. The NHTSA project used computational modeling to identify target geometry for belt anchors and placing wheelchair seating stations, which were then implemented in two test fixtures. The NHTSA project also designed and constructed an automated wheelchair securement system meeting specifications of the Universal Docking Interface Geometry (UDIG) that have been included in RESNA and ISO standards. Vehicle anchorages meeting the specifications were constructed, as were attachment designs for a commercial manual and power wheelchair. The occupant restraint portion of the AWTORS include an automatic seatbelt donning mechanism based on a past UMTRI prototype, but with geometric improvements. For the current project, volunteer testing was performed with 10 wheelchair users. Using the two study wheelchairs equipped with UDIG anchors, the study evaluated the usability of three wheelchair seating stations with different geometries, each with two different belt conditions, as well as conditions with the volunteer’s own wheelchair. Data included videos of ingress and egress, scans of volunteer posture, and questionnaires to document the time spent docking the wheelchair and donning the seatbelt, belt fit, comfort, and potential usability issues. Average time for entry, docking, and donning just over 2 minutes in all conditions. To collect additional data on the range of wheelchair sizes and occupant size and posture, additional 3-D measurements of people seated in their wheelchairs were gathered outside a local medical facility.

Klinich KD, Orton NR, Malik L, Zak E, St. Amour M, Manary MA (2021) Volunteer Evaluation of an Automated Wheelchair Tiedown and Occupant Restraint System. UMTRI 2021-04. University of Michigan Transportation Research Institute.