Force transducer based on a geometric-optical displacement sensor

Abstract

The vast majority of current force measurement methods determine the deformation of an elastic body to measure the effective force. The leading sensor technology in this market segment is the resistance strain gauge. Because of the measurement principle the stain gauge has some drawbacks. For instance, the measurement suffers from the so-called creeping and a local weakening of the elastic element is necessary to create sufficient local strains. This is also a reason for this technique being limited with respect to the measurement of dynamic loads. In order to overcome these limitations, in this paper a new contactless working geometric-optical displacement transducer is proposed. An optical lever principle is used to reach the required high position resolution to measure the force-induced deformation of an elastic body.