Figure 5. Model simulation of the angular velocity.

A) The modeled beetle in figure 1C showing that the point of contact with the ground should be within the red rectangle. The x axis of the rectangle is magnified in B. B) The model calculation for angular speed of somersaulting () as a function of the point of contact with the ground along the x axis. C) Model calculation of angular speed for rolling in the air () as a function of roll angle ψ of the body in the pre-jump posture. The longitudinal position of the point of contact with the ground is assumed to be x = 2 mm posterior to the hinge. The insert in C shows the beetle in cross-section, defining ψ and the moment arm. Red circle denote the center-of-mass.