Application of Passive Dynamic Walking Model to Gait Trajectory Estimation Using Inertial Measurement Units and LiDAR

This paper presents a method for accurately estimating gait trajectory. We have developed an approach that leverages observations from two inertial motion units (IMUs) attached to both insteps and light detection and ranging (LiDAR) mounted on the back. A key advantage of this method is that it does not require observing the person from a fixed point. However, there is potential to further improve the accuracy of the estimated gait trajectory, particularly because the geometry of the gait has been somewhat distorted. In this study, we introduce a passive dynamic walking (PDW) model to preserve gait geometry and detail the formulation for integrating it into the existing method. Additionally, we present a method to address trajectory discontinuities using the PDW model. The effectiveness of the method is explained based on the experimental results using real data.