Saskia Baltrusch

139 Chapter 5 4.2 Biomechanical testing Kinematics A typical time series of the range of motion testing is displayed in Figure 10. Good correspondence between the human and Exo angles were observed with correlation values above 0.98. Largest trunk flexion occurred in the No Exo condition and decreased with 16° and 41° for the Flex Slider and Rigid condition, respectively. In all cases, human peak angles while wearing the Exo decreased with respect to the No Exo condition. Bar plots indicating the peak angles of the range of motion trials and agreement between the Human and Exo peak angles are shown in Figure 11. In all three directions, peak angles were bigger in the Flex Slider condition compared to the Rigid condition. Almost no loss in ROM was found in lateral bending between No Exo and Flex Slider. However, between Rigid and Flex slider, lateral bending ROM decreased with more than 13°. As can be seen in the lower panel of Figure 11, a part of the improvement of the ROM is due to the effect of the slider and is thus not only due to the use of the flexible beams as was shown in the top panel of Figure 11. Figure 11b shows the agreement between the Human and Exo angles. In the no slider condition, agreement between Human and Exo lumbar flexion reduces with 18% compared to the agreement in the Flex Slider condition. In addition, a reduction of 47% is observed due to the difference between Flex No Slider and Rigid. Showing the benefit of the proposed features in both absolute angles as well as following the movement of different segments of the human. 5