One of the objective functions is to minimize the difference between the trajectory of the real and virtual insects. We here compare the joint angles at three DOFs on the middle leg for both the real and simulated subjects (Fig. 7). We found that the overall shape of the trajectory is consistent between the real and simulated cases. However in the result of real cases, the joint angles decrease to a minor extent before increasing incrementally. This is not observed in the simulated case, in particular for the body-coxa joint. This mismatch may be caused by the posture adjustment of real ants, or possibly by the hardware limitation (image resolution and framerate) of data collection. In the simulation case, the body-coxa joints move at a strict forward pattern in a single motion cycle.Figure 7Joint angles on the middle leg captured from real insects during a locomotion cycle. Dashed lines are trajectories from real ants, solid line (in bold) is from virtual ant with Hill-type muscle and dashed line (in bold) is from virtual ant with PD servo.