Study of Athlete’s Motion Identification Method using Gymnastics Apparatus with an Accelerometer

Abstract

In gymnastics, the skeleton of the athletes can be estimated from many points having three-dimensional coordinate data by measurement control using LiDAR (Light Detection and Ranging), and the motion can be known. However, the system cannot know what kind of load is being put on the athletes' bodies. Also, it is not possible to know in detail how top-level athletes handle apparatus. It is considered that if we can measure apparatus' motion and grasp the athlete's motion using the data, it will be possible to evaluate the load by the exercise and the accurate use of the apparatus. Therefore, it is important to understand the dynamic response of the apparatus to the athlete’s motion. However, it is not desirable to directly attach a sensor to the bar because it interferes with the competition. For example, if it is possible to grasp the deformation and stress of the apparatus by attaching sensors to the post end, the measurement can be carried out without affecting the competition. In this study, we measured the displacement of both ends of the bar with an accelerometer that can sense how the bar is deformed by applying a static load to the bar. It was shown that the deformation identification of the bar was possible by substituting these measurement results to both ends of the bar of the model using the finite element method as displacement quantity.