Development and Validation of Rear Impact Computer Simulation Model of an Adult Manual Transit Wheelchair With a Seated Occupant
By Salipur, Zdravko, Bertocci, Gina; RESNA Annual Conference - 2008,Publication Date: 2008
Study describes the development and validation of a computer model simulating an adult wheelchair-seated occupant subjected to a rear impact event. The model was developed in light of observations that WC19 wheelchairs that are crashworthy in frontal impact exhibit catastrophic failures in rear impact collision. Three identical ANSI/RESNA WC19, reinforced, manual, folding, X-braced wheelchairs were subjected to rear impact crash pulse of 28.8 kilometers per hour, 14 g acceleration. A Hybrid III anthropomorphic test device (ATD) represented the wheelchair-seated occupant. The wheelchair was secured using surrogate 4-point strap type tiedowns, while he ATD was restrained using a surrogate vehicle-mounted 3-point lap and shoulder belt system. Multiple views of the sled tests were captured using high speed digital cameras. The rear impact scenario was reconstructed using MADYMO (Mathematical Dynamic Modeling) software. Validation of the model involved matching the model outcome variables to those from the sled test results. The variables investigated in the model validation included (1) front tiedown loading, (2) wheelchair acceleration in the direction of travel, and (3) vertical wheelchair caster excursion. The failure of frontal impact crashworthy wheelchairs to protect the rider from rear impact was found to be due to the dynamics of a rear impact event, where the front tidedowns serve as the main means of securing the wheelchair, while the ATD moves rearward, loading the seatback. This model provides information that may be crucial in the production of rear impact safe transit wheelchairs. Study limitations and implications for future research are discussed.
Published by:
Rehabilitation Engineering & Assistive Technology Society of North America (RESNA) (Web Site: http://www.resna.org )
This publication is included in the library of the National Rehabilitation Information Center (NARIC), accession number O18071
