Temperature invariant force and torque sensor assemblies

Abstract

Various sensor assemblies are described herein that can measure axial and lateral forces and/or axial and lateral torques acting on an instrument independent of steady state temperature variations. In one embodiment, the sensor assembly has a sensor body for coupling to the instrument such that a shaft and tip of the instrument extend from opposing ends of the sensor body. The sensor body has first and second strain sensing regions. The sensor assembly further includes first and second strain sensors coupled to and configured to measure axial strain of the first and second regions, respectively. During use, when the sensor body is coupled to the instrument, each of the first and second regions experience an opposite one of a tensile axial strain and a compressive axial strain in response to an axial force or an axial torque acting on the tip of the instrument.