Research on a throwing information acquiring system for discus-throw athletes

In this paper, we present a novel motion detecting system. Embedded in a discus which has the same size and weight as a standard one used by male athletes, it can detect and record the motion data for the entire throwing processing to provide comprehensive throwing information for athletes and coaches. Called a digital discus, the overall system consists of embedded sensors, a discus, a wireless transmission and an upper PC. The sensor unit, including a 3D accelerometer and 3D digital gyroscopes, can acquire the three dimensional acceleration and angular rate of the discus in the entire discus-throwing duration. The wavelet transformation based motion detection algorithm is given. The system has been validated in field experiment showing its feasibility and effectiveness.