Chapter 18 - Mass, Force, and Torque Measurement

Abstract

This chapter covers the three separate subjects of mass, force, and torque measurement. Mass measurement, and the related quantity of weight measurement, is considered first, and the three distinct ways of measuring mass using respectively a load cell, a spring balance, and one of several instruments working on the mass-balance principle are explored. Moving onto the force measurement, it is noted that transient forces can be measured by an accelerometer, whereas static forces are measured either by a vibrating wire sensor or by a special form of load cell. Looking next to the torque measurement, the chapter reveals that the two main current methods for measuring torque are to measure the induced strain in a rotating shaft or to measure the torque optically, while also mentioning two older and lesser-used techniques in the form of firstly measuring the reaction forces in the bearings supporting a rotating shaft and secondly using a device called the Prony brake. Sections covering the calibration of mass, force, and torque sensors are also provided in the chapter.