Design of an inclined weight measurement system for prosthetic arm innovation

Abstract

Force feedback is one of the top critical aspects of prosthetic solutions. For patients equipped with powered prosthetic arms, their ability to grasp, manoeuvre and feel heavy objects is limited at rest and during exercises. This research approaches a solution that may help to solve the problem for many patients - a prototype capable of measuring the weight of objects automatically at multiple degrees of freedom of the patient’s prosthetic arm. By incorporating the existing technologies of a micro-electromechanical system capacitive accelerometer with a strain gauge force transducer, the weight of an object is measurable instantly the moment it is held, independent of any inclination. Results showed that the weight of an object measured at different 90° movement angles is similar to the actual weight of the object in use. The mean measurement error is approximately ±0.05 kg of the tested object's mass of 1.5kg at multiple inclines.