Dynamic analysis of the spinal-pelvic motion match during feline galloping for speed increase into quadruped robotic system

In terms of the speed performance in feline galloping, relative spinal motion is observed as a key role to increase the locomotion speed. In order to prove this, a domestic cat was observed to investigate galloping gait patterns of the feline. Based on the measurement of the dynamic behavior of a domestic cat, we observed a significant increase in speed through correlated angular rate changes of spinal segments. To support the motion into a quadruped system, the hindlimb stance phase was analyzed using a 2 dimensional planar dynamic model to verify that the external torque generated by spinal motion plays an important role in increasing the ground reaction force in the direction of movement. To verify the analysis, the dynamic simulation demonstrating the hindlimb stance was applied with 3 parameter variations: time, phase and the amplitude of the fitted relative angular velocity profile.