Optimal estimation of body angular velocity based on otolith-canal interaction

The human vestibular system, consisting of the otolith and semicircular canals, provides valuable information about body motion and orientation in terms of angular velocity and translational acceleration. This article discusses the dynamic characteristics of these organs and the generated signals and proposes approaches to combine these signals to infer for the body angular velocity. This is the first step towards determining the body orientation and thus the inertial acceleration. The first approach evolves around a complementary filter that capitalizes on the low- and high-frequency characteristics of the signals. The second approach resembles a Kalman filter that allows for explicitly estimating the drift of the semicircular canal signal.