The Design of a Three-Degrees-of-Freedom Walking Machine.

The walking machine presented in this paper consists of six walking legs arranged in a triangular configuration. Each leg may have two modes of operation: an elliptical mode for walking on a flat plane and a circular mode for stair climbing. The six legs are mechanically coupled to a single drive motor through the use of chains and sprockets. the coupling is arranged in such a way that three of the six legs, one from each corner of the triangle, are always in phase while the other three are 180 degrees out of phase. When walking, three of the six legs are always on the ground propelling the machine forward, while the other three are in the air in an opposing position rotating forward. Turning is achieved through the use of a two degres-of-freedom mechanism. Through the use of a prismatic joint, the body of the machine can be lifted up-anddown, and through the use of a revolute pint, it can be rotated to any desirable orientation. The result is a simple, three degrees of freedom, walking machine that is capable of walking on a flat plane and performing some limited stair climbing. Because of the simple construction, the control system is also extremely simple and fast locomotion may be achieved for a small sacrifice of flexibility