Fig. 3From: Finite helical axis for the analysis of joint kinematics: comparison of an electromagnetic and an optical motion capture systemRepresentation of the trajectory of one virtual point of the rigid body obtained by the analysis of the positions of the Elite markers and the FHA relative to each of the acquisitions. a side view b top view, c zoomed view d detail of the distribution of intersection points of the FHA with the horizontal planeBack to article page