Simple quantification of foot speed generating mechanism of soccer kicking using IMUs

Abstract

The purpose of this study was to examine the possibility of a system which realizes a simple quantification and immediate feedback of generating mechanism of kicking side leg during soccer instep kick, using inertial measurement units (IMUs). The angular velocity outputs of the IMUs attached on lower trunk, thigh, shank and foot segments can estimate the posture of each segment and carried out induced speed analysis. The dynamic contributions of the individual terms such as, joint torque term, gravitational force term, and motion-dependent term (MDT) to the generation of the foot center of gravity (CG)’s speed was quantified using the equation of the target system with estimated segmental position data. The results of this study show that almost good agreements between estimated motions with IMU outputs and measured motions obtained by a motion-capture system in terms of mechanism of the foot CG’s speed generation. Though there was a difference in joint torque term from the kicking foot take-off to support foot contact. Dynamic contribution analysis obtained from Constructed immediate feedback system with respect to the mechanism of speed generation using IMUs could be used to evaluate performance at sports fields.