Effect of Manual Wheelchair Caster Stiffness and Energy Absorption on Wheelchair-Occupant Kinematics During a Frontal Impact Using Computer Simulation
By Dsouza, R.; Bertocci, G.; van Roosmalen, L.; Rehabilitation Engineering & Assistive Technology Society of North America (RESNA) 2007 Conference,Publication Date: 2007
Study used a computer simulation model to examine the effects of manual wheelchair stiffness and energy absorption properties on wheelchair and occupant kinematics during a motor vehicle crash. Three parameters were varied during the study: (1) the caster stiffness was varied from 2750 lbs/in to 250 lbs/in from a baseline stiffness of 1750 lbs/in; (2) the R factor, the energy absorption function, which is used to specify the amount of energy recovered at the end of unloading; and (3) the G factor, the permanent deflection function used to model permanent deformation due to contact force. Both R and G values can range from 0 to 1. Analysis of the crash simulations for various caster stiffness scenarios indicated that a caster stiffness greater than 1750 lbs/in made no significant changes to the wheelchair and occupant kinematics. However, caster stiffnesses lower than 750 lbs/in increased the risk of lap belt submarining. The results suggest that caster stiffnessed between 1750 and 750 lbs/in, along with an R factor between 0 and 0.5 and a G factor between 0.75 and 1 can improved overall kinematics by removing energy from the wheelchair and occupant during a frontal impact. This paper was presented at the 2007 Annual Conference of the Rehabilitation Engineering & Assistive Technology Society of North America.
Published by: Rehabilitation Engineering & Assistive Technology Society of North America (RESNA) (Website:http://www.resna.org)
