Rozhraní strunových čidel pro distribuované měřicí systémy

Abstract

Relatively small displacement or deformation is necessary to measure on the various structures and objects under study in geomechanical and geotechnical engineering, geology, civil engineering and many other industries. Vibrating wire crackmeters are the most widespread and the most reliable sensors for the measurement of displacements and deformations. Multiple objects are necessary to measure simultaneously in most of these applications. Sometimes, it is also required comprehensive monitoring of several different variables - not only deformation – for one given object. In such cases, it is not practical to implement a system of continuous monitoring using mechanical or electrical strain gauges that required attendance of staff. Therefore, electronic automatic measurement networks are used. The aim of this work was to design solution of a prototype interface of vibrating wire crackmeters that is possible to apply in E-M noisy industrial environments connectable to a distributed measurement systems that used the AIBus – 2 protocol for communication. Determination of eigenfrequency of vibrating crackmeter response is based on analysis of frequency spectrum of signal response that is calculated using Fast Fourier Transform.