Controller tuning for a four-legged locomotion robot

The aim of this paper is to present the lower level control system that is used to drive the 12 DOFs of a four-legged locomotion robot, Rimho. Focusing on the discontinuous gait, and from the digital control point of view, three main dynamic phases are identified, and the research is concentrated on the individual tuning of the twelve controllers, so that all joints present quite similar time response characteristics. After that, a realistic, simple and very practical approach consisting in the updating of the digital filter parameter setting along the different gait phases is adopted, and its behaviour is illustrated by means of several experimental results