The authors have been using the ZMP (Zero Moment Point) as a criterion to distinguish the stability of walking for a biped walking robot. If the ZMP during robot walking can be measured, it is possible for a biped robot to realize stabler walking by a control method that makes use of the measured ZMP.
In this paper, a method that measures the ZMP throughout the whole walking phase is proposed. A ZMP measurement system using two universal force-moment sensors is developed and installed into a biped walking robot. The accuracy of the ZMP measurement system is experimentally confirmed, and the ZMP throughout the whole walking phase is measured.