Development of six-axis force/moment sensor for an intelligent foot of humanoid robot

This paper describes the development of 6-axis force/moment sensor considered adult weight for an intelligent foot of humanoid robot. In order to walk on uneven terrain safely, the foot should perceive the applied forces Fx, Fy, and Fz, and moments Mx, My, and Mz to itself, and control the foot using the measured them. The applied forces and moments should be measured from a 6-axis force/moment sensor attached to the foot. In this paper, a 6-axis force/moment sensor for perceiving forces and moments in a humanoid robot´s foot was developed using many PPBs (parallel plate-beams). The structure of the sensor was newly modeled, and the sensing elements (plate-beams) of the sensor were designed using FEM (Finite Element Method), following which the 6-axis force/moment sensor was fabricated by attaching strain-gages on the sensing elements, moreover, the characteristic test of the developed sensor was carried out. The rated outputs from FEM analysis agree well with those from the characteristic test.