The use of Kalman filtering in assistive device for data assessment and control in gait re-education

In the paper an application of Kalman filter technique in rehabilitation engineering is presented. The functional electrical stimulation (FES) is frequently applied motor augmentation aid in incomplete spinal cord injury that is in a need for modification. Therefore the gait reeducation system was proposed that successfully applies the presented algorithm. The proposed sensory system is equipped with dual-axial accelerometer and a gyro and is placed at the shank of the paretic leg. The data assessed present input into mathematical algorithms applied for shank angle estimation. The algorithm is based on Kalman filter estimating the angle error and correcting the actual measurement. The proposed method was tested during healthy subjects walking on even terrain and treadmill. Afterwards the comparison with optical measurement system Vicon was performed and the triggering of the KES was also tested. Outcome of the measurements clearly shows how sensory integration algorithm may serve the purpose and its precedence over the single sensor applications.