Novel Evaluation Tool for Wheelchair Racing Performance: Precise Adjustment of the Wheel Axle and Torque Measurement during Wheelchair Propulsion

Abstract

To gain a deeper and more detailed understanding of the mechanisms underlying propulsive force generation in wheelchair racing, we developed a testing simulator that enables us to perform precise adjustments of wheelchair-settings. The system incorporates adjustable parameters, such as the camber angle, wheel position, and driving load, allowing for the precise replication of a realistic wheelchair racing situation. A pair of torque meters on the simulator's axles enable direct measurements of wheel torque and velocity. A test pilot who is an elite wheelchair racer with SCI (T52, World Para Athletics Medalist) participated in our comparison of three conditions with different wheelchair-settings: (1) original, (2) camber anglemodified, and (3) wheel position-modified. We analyzed the wheelchair racing performance, such as wheel speed, total torque output, and the timing of torque generation. We quantified the relationship between the hand and handrim position and observed that the timing (angle) of peak torque generation was 107.1 ± 3.8°. The results indicated that higher wheel speed (277.4 ± 2.6, 301.2 ± 2.6, and 283.1 ± 3.8 rpm) and deeper peak torque angle (107.1 ± 3.8, 123.7 ± 5.4, and 122.5 ± 13.0°) in the camber angle and wheel position-modified settings compared to original setting. A quick and precise modification with our developed simulator offers insights not only for the improvement of performance but also for the customization of individuals' racers. Our findings demonstrate the utility of torque measurement in understanding racing wheelchair propulsion mechanisms, contributing to advancements in para-athletics and wheelchair-settings based on individual residual functions.