Development and Preliminary Validation of a Low-Cost Portable Tool for Assessing Joint Mobility
Mayss Alreem Nizar Hammed
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Electrical Engineering Technical College, Middle Technical University, Baghdad, Iraq
DOI: 10.18287/JBPE26.12.010302
Abstract
This paper presents the development and preliminary feasibility evaluation of a small, low-cost computer-aided device for joint measurements in humans with the aid of a flex sensor attached to an Arduino Nano. Commercially available goniometers are frequently either costly or complex and require a calibration kit that is not feasible for healthcare and rehabilitation facilities with scarce resources. A solution is therefore needed that does not rely on extensive access facilities, and the proposed device is designed to fill this requirement. Preliminary measurements on a single healthy participant verified the system’s initial functionality as proof of principle. Descriptive comparison with readings from a reference goniometer of joint-angle measurements. Finally, the system achieved a mean absolute error (MAE) of 8.21° and a mean absolute percentage error (MAPE) of 16.73% with better performance in joints that present larger ranges (e.g., elbow and knee) compared to smaller ones or rotational movements. As a proof-of-concept, this study sets the stage for future research that will include multi-participant testing and post-processing and improved mechanical alignment and calibration procedures to further improve measurement accuracy.
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