A novel inertial technique to measure very high linear and rotational movements in sports, part I: The hardware

Abstract

In sports biomechanics, videography provided an indirect measurement method for measuring sport movements. However, these techniques are expensive, bulky and not portable. A novel inertial data logger designed to record the linear and rotational movements in three axes at 200 Hz and save the data on a memory card. A custom PC software was developed to measure the kinematics parameters (linear and angular accelerations and velocities) and compute the kinetic parameters (force, torque, angular momentum, impulse and angular power) of the attached limb during performance. The current system is applicable in sports that involve high linear and rotational kinematics and high impact contact. Evaluation of the sensor module at 500 °/sec showed very good validity and reliability of angular velocity (r = 0.954, p<0.0001; Cronbach's Alpha = 0.973) and angular acceleration (r = 0.905, p<0.0001; Cronbach's Alpha = 0.960), respectively as compared to values obtained at 300 and 210 °/sec. It is able to measure angular velocity up to ±100,000 °/sec and linear acceleration up to 2,452 m/sec2. This is light, cheap, reliable, robust and accurate system to measure high kinematic and kinetic parameters in the field. This approach is in contrast to current high-tech videography systems that are expensive, bulky and cumbersome. This novel technique is suitable in Soccer. Rugby, American Football, Tennis, etc. to evaluate the player's performance in the field. © 2009 Asian Network for Scientific Information.