The Measurement of Force and Torque Using Capacitor Devices

Abstract

This paper concerns the use of electrical capacity in the measurement of force and torque as an alternative to conventional strain gauges. It has been established that for some requirements mechanical configurations can be designed with integrated capacitor bridges which combine a good performance with low cost and compactness. Simple electronic circuitry incorporating multiplexing has been developed and used to drive multi-axis devices. Examples include a configuration for measuring the three torques at a point. Work on an integrated circuit shows the possibility of positioning the electronics within a device with a serial digital interface to a host computer.