Wheelchairs used as motor vehicle seats: seat loading in frontal impact sled testing

Wheelchairs are not typically designed to function as motor vehicle seats. However, many wheelchair users are unable to transfer to a vehicle seat and instead travel seated in their wheelchair. ANSI/RESNA WC19: Wheelchairs Used as Seats in Motor Vehicles provides design and testing requirements, but does not provide wheelchair manufacturers with design guidance related to expected loads imposed upon wheelchair components during a crash. To provide manufacturers with crashworthy design guidance, our study measured wheelchair seat loading during 20g/48kph frontal impact sled tests with a 50th percentile male test dummy. Loading conditions were assessed using two different rear securement point positions. Results of four sled impact tests revealed downward loads ranging from 17 019 to 18 682 N, depending upon rear securement point configuration. Maximum fore/aft shear loads ranged from 4424 to 6717 N across the tests.