Fig. 7. Histograms of frame-wise difference between motion analysis and inertial sensor for roll, pitch and heading angles and x, y and z displacements for the whole data set. Histograms are shown for (A) walk (1.4 m s^-1), (B) trot (3.5 m s^-1) and (C) left lead canter (9.0 m s^-1). The spread of the histograms is generally increasing from walk to trot and canter. In addition, there is an offset in roll and pitch orientation, which increased with speed.