A Polyetheretherketone Six-Axis Force/Torque Sensor

Abstract

At present, six-axis force/torque (F/T) sensor has been increasingly used in robot application, and most of the elastic elements of resistance strain type F/T sensors are made of metal materials, such as alloy steel, stainless steel, aluminum alloy, and so on. In this paper, a novel six-axis F/T sensor based on Polyetheretherketone (PEEK) material is presented. Comparison with ordinary F/T sensor purpose was served by building simplified statics model that demonstrates the conclusion of highly sensitivity of the F/T sensor based on PEEK material. The strain mapped on the strain sensitive path was analyzed using finite element analysis (FEA), frequency response curves were depicted by means of harmonic analysis, and the static and dynamic performances analyses of the six-axis F/T sensor based on PEEK material (later called PEEK sensor) were studied. Moreover, the properties of this sensor were compared with a six-axis F/T sensor based on aluminum alloy 2024 material (later called metallic sensor). The results show the properties of linearity (≤1%), hysteresis (≤2%), high sensitivity (force: ≥ 2.37×10^-4/N; torque (Tx, Ty): 0.19×10^-4/Nmm), and crosstalk (≤8%) between the dominant F/T component and other components. The dynamic response time of the PEEK sensor was also measured via dynamic calibration experiment, which is much higher than that of the metallic sensor. This study demonstrates that the PEEK sensor has a comparable static performance with the metallic sensor, and even higher sensitivity, but it is only suitable for measurement below 200 Hz.