Figure 3

Examples of stability index (SI) and its derivative (\(\tilde{S}I\)) for simulation (left) and experimental (right) data. Vertical axis represents averaged SI or \(\tilde{S}I\) for each on (dark blue) and off (light blue) period. Left: SI (top) and \(\tilde{S}I\) (bottom) 200 ms before each on/off period for simulation data. Right: SI (top) and \(\tilde{S}I\) (bottom) 160 ms before each on/off period of rectus femoris (RF) of one participant (ID = 6).