5525 Measurement of forearm movement during high-speed pitch using inertial sensors
Details
Measurement method of three-dimensional trajectory of forearm during baseball pitch using body-mounted sensor is discussed. From the optical motion capture system, it is estimated that the acceleration and the angular velocity of the arm reach up to 100 [G] and 8000 [deg/s], respectively, when the professional level baseball pitchers play the best throw. Three-dimensional, low gain accelerometers and gyroscopes in addition to high gain sensors are employed to avoid the saturation of the measured signals from the sensors. The trajectory and direction of the forearm are calculated based on the numerical integration of the acceleration and angular velocity. Integral errors are rejected by the definition of initial and final velocity, position and direction of the forearm. The experimental results showed that the estimated position and angle of the forearm highly corresponded with the video image. The proposed method enables easy, inexpensive and independent measurement from location.
