Motion analysis method and motion analysis device

Abstract

A motion analysis device includes a calculation unit which specifies a first imaginary plane, that is, a shaft plane formed by a first line segment representing a direction in which a shaft part of a sporting gear in a static posture extends and a second line segment representing a ball hitting direction, with the use of an output from an inertial sensor.

Description

BACKGROUND[0001]1. Technical Field[0002]The present invention relates to a motion analysis method and a motion analysis device.[0003]2. Related Art[0004]For example, in golf, which is a specific example of sports, the concept of the swing plane is commonly known. The swing plane is equivalent to the trajectory of the golf club when swung. For example, according to JP-A-2009-20897 and JP-A-2008-23036, a golf swing made by a subject is shot with a camera from behind the subject and the swing plane is specified based on the shot image.[0005]The technique for finding the swing plane according to JP-A-2009-20897 is to find at least two specific points in the swing from image data and analyze the swing plane based on the two points. In this technique, first, after the swing is finished, it is necessary to edit the image data and carry out work to find specific points. Therefore, there is a problem that a large discrepancy from the actual swing plane is generated and also a problem that it...

AI Technical Summary

Benefits of technology

[0007]An advantage of some aspect of the invention is that a motion analysis method and a motion analysis device are provided which are capable of presenting a clear indicator in analyzing the motion of a swing.

[0009]To establish the static posture of the sporting gear, the subject reproduces the posture at the moment of impact. As a result, the posture at the moment of impact is extracted from a series of movements called “swing”. The inertial sensor outputs a detection signal according to the posture of the sporting gear. The first imaginary plane is specified according to the detection signal. The first imaginary plane can depict an imaginary trajectory of the sporting gear swung in the swing. The trajectory of the sporting gear in the swing is observed in comparison with the imaginary trajectory. The movement of the subject is analyzed, based on the trajectory of the sporting gear. Thus, a clear indicator is provided with respect to the motion “swing”. According to this configuration, in the case of a golf swing, the first imaginary plane can be regarded as the shaft plane, and for example, based on the inclination of the shaft plane when the subject is at address position, the subject can grasp the difference in the distance between the subject and the ball and the difference in the posture of the subject and can thoroughly examine the causes of good or bad ball hitting.

[0011]According to this configuration, an acceleration sensor is used as the inertial sensor. Based on the output from the acceleration sensor in the static posture, for example, how much the shaft of the golf club is inclined with respect to the direction of gravity can be found. Using the inclination information and the length information of the shaft, the shaft plane can be easily specified.

[0014]According to this configuration, the second imaginary plane can be regarded as the Hogan plane, and for example, based on the inclination of the Hogan plane when the subject is at address position, the subject can grasp the difference in the distance between the subject and the ball and the difference in the posture of the subject and can thoroughly examine the causes of good or bad ball hitting.

[0016]According to this configuration, an acceleration sensor is used as the inertial sensor. Based on the output from the acceleration sensor in the static posture, for example, how much the direction in which the subject's arm extends is inclined with respect to the direction of gravity can be found. Using the inclination information and the length information of the arm, the position of the subject's shoulder can be specified and the Hogan plane can be easily specified.

[0019]According to this configuration, for example, in the case of a golf swing, the first imaginary plane can be regarded as the shaft plane, and the second imaginary plane can be regarded as the Hogan plane. Then, for example, based on the inclination of the Hogan plane when the subject is at address position, the subject can grasp the difference in the distance between the subject and the ball and the difference in the posture of the subject and can thoroughly examine the causes of good or bad ball hitting.

Problems solved by technology

Therefore, there is a problem that a large discrepancy from the actual swing plane is generated and also a problem that it is time-consuming to display the swing plane.

The technique of JP-A-2008-23036, too, requires some work to edit image data and therefore has similar problems to those of JP-A-2009-20897.

Therefore, there are no previous measures to present the shaft plane and the Hogan plane easily and accurately to the golfer in golf swing analysis.

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