Quaternion based attitude estimation algorithm applied to signals from body-mounted gyroscopes

An application of inertial sensing to gait analysis is described: the attitude estimation algorithm computes the attitude quaternion associated with a body part, i.e. the foot instep moving in the inertial space, by employing a spherical linear interpolation procedure to compensate for the errors due to the influence of the gyroscope bias. The effectiveness of the approach is demonstrated by simulations.