Measurement method of drop jump motion using inertial sensor

Abstract

The purpose of this study was to investigate the measurement method of drop jump movement by calculating quaternions using a sensor fusion technique based on the Madgwick AHRS algorithm, which is one of the complementary filters. Two healthy adult males were asked to perform a drop jump from a 0.3 m high box with a waist pouch containing an inertial sensor attached to the back of the waist. The test was performed on a force plate and shot using two high-speed cameras that were perfectly synchronized. The Madgwick AHRS algorithm was applied to the acceleration and angular velocity obtained from the inertial sensor, and calculated the acceleration transformed from the sensor coordinate system to the global coordinate system. Linear acceleration was calculated by removing the effect of gravity from the global acceleration, and linear velocity was calculated by time integration and ZVC correction. By using the vertical components of linear acceleration and linear velocity, we were able to obtain data with the same accuracy as the data obtained from digitization and force plates, and we were able to estimate the ground contact time, jump height, and DJ-index to evaluate the drop jump.