The design and implementation of a wearable system to estimate the human reaction time (HRT) to visual stimulus based on two identical wireless motion sensors are described. Each sensor incorporates a motion sensor (gyroscope), a processor and a transceiver operating at the industrial, scientific and medical frequency of 2.45 GHz. Relevant tests to estimate the HRT are performed in two different scenarios including simple and recognition tests for 90 pairs of measurements. The obtained results are compared with a computer-based system to determine the accuracy of the proposed system. The root mean square error, standard deviation error and mean error of the results are 2.88, 6.17 and 0.3 ms for simple test while for recognition test as low as 3.34, 7.83 and 0.35 ms, respectively. The outcomes of the HRT estimation tests confirm HRT can increase by 40-87% due to increased fatigue levels.
Keywords: HRT; biomechanics; fatigue; fatigue levels; frequency 2.45 GHz; gyroscope; gyroscopes; human reaction time; mean error; mean square error methods; recognition test; root mean square error; simple test; standard deviation error; telemedicine; time 0.35 ms; time 3.34 ms; time 7.83 ms; transceiver; transceivers; visual perception; visual stimulus; wearable system; wireless motion sensors; wireless sensor networks.