2DOF Link Mechanism Mimicking Cheetah's Spine and Leg Movement.

A spine of a quadruped animal has compliantly connected several segments. This structure enables the animal to realize bending/stretching motion during running along with the motion of the legs. In this paper, we describe a link mechanism for mimicking such bending/stretching motion of the spine and the leg with few degrees of freedom. By designing a linkage mechanism, we try to realize a similar motion of the spine and the hind leg as that of a cheetah. We developed a prototype with such a structure and demonstrate that it can realize the similar movement of the spine and the leg as that of a cheetah with a simple control strategy.