EVALUATION OF TITANIUM ULTRALIGHT MANUAL WHEELCHAIRS USING ANSI/RESNA STANDARDS
A series of commercially available titanium ultralight wheelchairs were tested using ANSI/RESNA testing procedures, and their durability was compared with previously tested aluminum ultralight wheelchairs and light-weight wheelchairs. Three of each of the following titanium wheelchairs were tested: Invacare-TopEnd, Invacare-A4, Quickie-Ti, and TiLite-ZRA. The Quickie-Ti wheelchairs had the most forward and rearward center of gravity adjustability. All of the titanium wheelchairs passed the forward braking effectiveness test, but two chairs of each model tipped backward before the platform inclining to 7 degree in the rearward braking effectiveness test. All titanium wheelchairs passed the impact strength tests, but two failed in the static strength tests: two Invacare-TopEnd wheelchairs and one Invacare-A4 wheelchair failed due to deformation of the armrest mounting plates, and the handgrips of the TiLite-ZRA wheelchairs slid off the push handles. Two Invacare-A4 and one Invacare-TopEnd successfully completed the double drum and curb drop tests, but the remaining 9 wheelchairs failed prematurely. No significant differences were found in the number of the equivalent cycles or the value among the four models. The titanium ultralight wheelchairs had less equivalent cycles and value than the aluminum ultralight wheelchairs that were tested in a previous study. The failure modes in the static strength tests and the fatigue tests were consistent within the model, and revealed important design issues for each model. Our results suggest that manufacturers need to perform more careful analyses before commercializing new products.
Advisor:Jon Pearlman; Rosemarie Cooper; Rory A. Cooper
School:University of Pittsburgh
School Location:USA - Pennsylvania
Source Type:Master's Thesis
Keywords:health and rehabilitation sciences
Date of Publication:09/08/2008