High Dynamic Range 6-Axis Force Sensor Employing a Semiconductor–Metallic Foil Strain Gauge Combination

Abstract

This letter proposes a force sensor that combines semiconductor strain gauges and metallic foil strain gauges to present force information of a higher dynamic range to robots. The strain gauges have different sensitivities, with semiconductor strain gauge sensitivity being approximately 90-fold than that of the metallic foil strain gauges. Using this difference in sensitivity, large forces and small forces are both detected through the two types of strain gauges and high dynamic range force detection is achieved by combining the output signals of these two. It was confirmed from the SN ratio test that the proposed sensor has a measurement range from 0.005 N to 1000 N, the maximum load. The dynamic range is 2 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\times 10^5$</tex-math></inline-formula> , extending the dynamic range of the 6-axis force sensor with the highest range in previous studies two-fold.