Miniaturization of multistage high dynamic range six-axis force sensor composed of resin material

Accurate force sensing is essential for skilled robot motion, while the limitation of the dynamic range is one of the major issues for force sensing. This paper deals with the development of a miniature six-axis force sensor with the aim of enabling robotic force detection across a high dynamic range (HDR). A miniaturized structure for the multistage structure of the HDR force sensor is designed by horizontally arranging two bodies: a low-rigidity thin beam inside a high-rigidity thick beam. The proposed sensor demonstrated performance superior to that of a conventional force sensor in the low load region, even with the inexpensive and lightweight resin material. Although creep and stress relaxation degrade the sensor's accuracy, these effects could be reduced by 80 percent with a correction filter.