A strain gauges platform for vertical jumping study

The aim of this work is the realization of a strain gauge platform for studying the human body gesture. This mechanical system is fed by a special instrumentation for measuring the ground reaction force during a vertical jumping phase. Four composites sensors that support the whole rigid plate were realized with metallic strain gauges. The low level signal at the output was carefully amplified and earned out to a PC computer via a special data acquisition card for subsequent signal analysis. In this paper, special features were dedicated to study the whole phase during successive jumps conducted by an athlete and experimental tests have been carried out for this purpose. The output signals were reported and a particularity was given to the power spectrum when the athlete takes off. The analysis puts into evidence the vertical jumping behavior and anomalies is especially studied in the falling down moment.