Abstract：A brief discussion and comparison on the existing methods of measuring the stability margin on legged loco-motion is given in this paper.Based on these methods,an improved and dynamic measuring criterion,i.e.the mechanical energy stability margin,is presented.The new criterion of measuring takes into account boththe characteristics of supporting ground and the dynamic effects of walking velocity on legged robot.The newmeasuring is of great importance to the researches on dynamic walking.
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