Is IMU-Based Center of Mass Estimation Reliable? Preliminary Study in Perturbed Conditions

Falls, often occurring during walking, are a major health concern. Clinical stability evaluations are typically subjective and lack standardized methods. There is a need for objective, easy-to-implement, and standardized methods to evaluate stability in clinical settings. Inertial measurement units (IMUs) offer a potential solution, but their accuracy needs validation in this context. We performed an exploratory analysis of a commercial (Xsens MVN, Movella, Netherlands) IMU-based center of mass (CoM) estimation, often needed in stability analysis, under various perturbations induced by the split-belt treadmill of the CAREN system from Motek. Results suggest that, although IMUs trajectory estimates are more accurate than velocity and acceleration, all estimates still present important deviations from those obtained by optoelectronic systems.