DEVELOPMENT OF TEST METHODOLOGIES FOR DETERMINING THE SAFETY OF WHEELCHAIR HEADREST SYSTEMS DURING VEHICLE TRANSPORT

For wheelchair users unable to transfer to a vehicle seat, the wheelch air serves as a means of mobility and postural support during activiti es of daily living and as a seating support in a vehicle. The performa nce of commercially available adaptive seating components in a dynamic or impact situation, as well as their effect on the safely of the use r, is unknown and should be determined, The main objective of the proj ect was to develop a test methodology to statically determine the cras hworthiness of wheelchair headrest systems and show the efficacy of th at methodology by applying it to several commercially available headre st systems. The methodology was based on Federal Motor Vehicle Safety Standard (FMVSS) test conditions, which use static test procedures to ensure that vehicle head restraints will perform adequately during act ual crash conditions. The procedure developed to evaluate the headrest s gave informative and repeatable results. The tests performed calcula ted the energy associated with a critical deformation of the headrest under quasi-static conditions, The results were used to determine the level of safety provided by the devices and to recommend design improv ements. The headrests tested exhibited similar modes of deformation du e to bending of a vertical adjustment bar, and several devices were de termined to be capable of providing adequate restraint in an impact si tuation.