Studies on Orientation Measurement in Sports Using Inertial and Magnetic Field Sensors

Abstract

This paper proposes a measurement system and computation method for 3D motion analysis in sports. The measurement system that consists of inertial and magnetic field sensors is able to measure 3-axis angular velocity, 3-axis acceleration and 3-axis magnetic field. We can easily perform the experiment in sports because this system is directly attached to the body. Introducing the sensor fusion algorithm using Kalman filter, we can avoid storage error by the drift of the gyro sensor. The computation method provides the angles by compensation of centrifugal and tangential acceleration and sensor fusion. In order to confirm the accuracy of this proposed system and computation method, we compared the value obtained by this system with the value obtained by a rotary encoder. It was found that the measurement system and computation method provided the accurate value. It is shown that the proposed method can be used for motion analysis in sports.