Figure 4. Results of sagittal, back and top views of the three mean trajectories of the right wrist of a single participant: the trajectories directly measured with marker-based stereophotogrammetry system (MBS, black line); the trajectories estimated from stereophotogrammetric data applying the kinematic chain model (KMS, dark grey line); the trajectory estimated from inertial sensors data applying the same model (IMMU, bright grey line).