Research Projects

Motion Estimation Using Point Cluster Method and Kalman Filter

Merav Mor, Alon Wolf

 The most frequently used method in three dimensional human gait analysis involves placing markers on the skin of the analyzed segment. This introduces a significant artifact which strongly influences the bone position and orientation and joint kinematics estimates. In this research study, We tested and evaluated the continuation of adding a Kalman filter procedure to the previously reported Point Cluster method (PCT) in the estimation of a rigid-body motion. We used the Vicon Motion system which is considered one of the gold standard systems for biomechanics study and measurements. Initial results indicate that when comparing the maximal amplitude, adding the Kalman filter had no effect on the results; however, a closer look at the signal revealed that the estimated angle based on the PCT method only was very noisy with fluctuation, while the estimated angle based on the method using PCT and the Kalman filter was a smooth signal.  Furthermore, it can be concluded that adding a Kalman filter to the PCT procedure substantially reduces the dispersion of the maximal and minimal instantaneous frequencies.

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