Projeto e construção de um ergômetro para cadeirantes

Abstract

Currently the majority of physical fitness evaluations of wheelchair users are carried out using arm crank ergometers. This kind of equipment is subjected to signal errors due to the discrete sampling of the power generated. Also, the arm crank ergometers can not reproduce the wheelchair user motor gesture throughout the wheelchair propulsion or respect the specificity principle. There are other equipments available in the market such as ergometers of rollers where the wheelchair user puts in motion his wheelchair on cylinders that possess sensors of torque and rotation. This kind of equipaments has high dimensions, weight and cost meeting out their use in training centers. There are arm crank ergometers adjusted to wheelchair users, but they are not widely applied because the use of mechanic brakes and limitations in the torque and rotation adquisition. The aim of this work is to design and construct of a wheelchair ergometer prototype for application of aerobic and anaerobic tests in disable people to evaluate the physical fitness. The prototype was designed respecting the motor gesture of a wheelchair user, allowing evaluations in the same conditions of sports practicing sports and daily life activities. The assembled ergometer was named ERG-CR09. It is formed by a structure of propulsion of the handrims and sustentation of the wheelchair user and another structure that corresponds to an electromagnetic system of generation of resistance. The structural part of the ergometer was evaluated through a numerical model of finite elements. A new analitical model is proposed to predict the propulsion force in a wheelchair. This model was previously validated with experimental data. The calibrations and analyses of the electromagnetic resistance module and the interface in LabVIEW environment was developed in another study and will be presented briefly. The validation and analysis of the ergometer prototype for wheelchair users was made using the Wingate test, applied to 16 volunteers. The tests showed that the constructed equipment allows adequate evaluation of the physical fitness of wheelchair users.