Kalman filter application for tracing and analyzing of ankle foot complex movements

M. Kalaidjieva, S. Karastanev, R. Antonova

Abstract: The paper introduce the application of Kalman filter which monitoring in real time series of measurements contain noise and other inaccuracies. These data are received from two-axial acceleration sensor (ADXL- 203) and gyro sensor (IDG-300 Dual Axis Outputs Xout/Yout) placed on ankle foot complex. The sensors measure acceleration ax and ay and angular velocity ω.
The main advantage of Kalman filter is that may eliminate most of measurement noise from accelerometer. It also helps to reduce the drift problem from gyro sensor. Another benefit of Kalman filter is its ability to minimize an average error obtained by the sensors. We use the Kalman filter algorithm as a tool that provides a reliable assessment for the state of the measurement process as well as for correction of ankle inclination measured by gyro sensor.
The proposed method provides excellent abilities for tracing and analyzing of the ankle foot complex movements.
By measuring the position and body segments orientation can calculate different biomechanical parameters such as joint angles, joint moments, velocities and accelerations.
The received data is widely used in the fields of bioengineering, rehabilitation, orthopedics and sports.

Keywords: ankle-foot complex; gyro and accelerometer sensors; Kalman filter

Date published: 2013-03-09