Figure 4.
Leg unloading is linked to loading of posterior neighbouring leg. (a) Touch-down events of all legs (top) and likelihood of touch-down per leg (bottom) relative to the onset of unloading, tUL, in the right middle (RM) leg (n = 244 steps from N = 10 animals). Touch-downs of the right hind (RH) leg reliably precede tUL in the middle leg with short latency (arrowhead). The box marks the step shown in b. (b) Exemplary stance phase showing the CTr torque of the right middle leg from the experiment (black) and the static model (grey). Horizontal bars on top indicate the stance phases of all legs. Vertical lines highlight the times of leg touch-downs. Touch-down induced changes in simulated torque provide a measure of a leg's unloading efficacy. (c) Simulated efficacy of legs in unloading the right middle leg, pooled across all steps. The 50% line corresponds to 50% of the mean torque measured during walking (figure 2a). (Online version in colour.)