An Efficient Forward Gait Control for a Quadruped Walking Robot

Abstract

Study of walking robots started in the mid 60s when an initial prototype of a quadruped robot was built and tested by General Electric Corporation. Since then, much work in this area by various researchers has resulted in the uncovering of many problems. At one end of the spectrum, these problems deal with low-level, but critically important issues such as gait control, force-feedback control for terrain-adapted foot-placement, stability, etc. At the other end, there are problems of dynamic control, the incorporation of environment sensing, collision avoidance, goal attainment, and others. This chapter presents a simplified forward gait for a quadruped walking robot. The proposed gait is a straight line, periodic, monotonically forward (SLPMF) gait. It is shown that for a given support pattern (a support pattern is a polygon generated by connecting the feet positions in contact with the ground) and for a given location of the robot's center of gravity, only certain sequences of leg movements will generate the SLPMF gait. A method to determine how to preserve stability of a quadruped robot during the motions called for by an SLPMF gait is also introduced. Experimental results are presented to support the feasibility of the proposed gait. Another noteworthy aspect of this chapter is the discussion on the leg design from a hardware standpoint; the design permits independent joint control.