Development and testing of an allterrain wheelchair built with light magnesium alloy to improve the mobility of the rural population

Abstract

The objective of this work was to design and test an all-terrain wheelchair for the rural population, implementing an AZ31 magnesium alloy and a lever propulsion mechanism to reduce the effort made during mobility. Two wheelchair prototypes were evaluated under the ISO7176 standard and usability testing. To validate the fact that the wheelchair weight reduction represents a benefit, a repeated measures study was carried out to establish the effect of the material change on mobility efficiency. The tests were carried out in an academic campus in Colombia in an open space with a surface covered with grass, unevenness, and other obstacles to emulate the conditions of a rural environment. A convenience sample was used, randomly selecting 17 subjects from the academic community without disabilities or overweight. Two prototypes were manufactured, one in aluminum and the second in magnesium alloy. For the study of repeated measurements, each participant had to complete three tests with both prototypes: a short-dis ance test, an obstacles test, and a long-distance test, which were performed randomly. The magnesium alloy prototype achieved a 25% weight reduction. In ISO7176 testing, both prototypes maintained their structural integrity and functionality. Also, with a confidence of 95%, it was possible to establish that with the magnesium prototype, the users traveled a greater distance in the same time. The new design meets the needs of mobility, support, and comfort of users, making efficient use of magnesium alloy. Weight reduction in the wheelchair allows the user to save time on mobility or cover greater distances with less physical effort. This is a starting point to offer a contextualized and affordable product to the Latin American population.