Fig. 5. Model of alligator during spinning maneuver. The head and tail are modeled as ellipsoids with circular cross sections. The tail is modeled as a elongate right circular cone. The semi major (a) and semi minor (b) axes of ellipsoids are exemplified on the body. Angular displacements of the head () and tail () are shown relative to the symmetry axis of the body. Angular velocities (_H, _B, _T) of body parts rotate together. The local Cartesian coordinate system is illustrated along the symmetry axis for each body part. The roll axis (RR') is indicated by the broken line at a distance (d) from the symmetry axis of the body. The angular velocity (_rev) around the roll axis is opposite in direction to the angular velocities of the body parts. The inset illustrates the vector angular momenta for the entire system. The vector sum of the angular momenta is zero for the motions of the alligator during the spinning maneuver.