Development of Signal Conditioning Circuit of a New Strain-Crack Detecting System

摘要

Crack and strain detecting is an important part of Structure Health Monitoring for aircrafts in fatigue environment.A signal conditioning circuit of a new strain-crack detecting system is developed in this paper.This circuit can deal with both intelligent coating sensor and strain gage,which have a great different original resistance between the two kinds of sensors.Comparing to the Wheatstone Bridge,when the strain is being detected,the new circuit gets rid of the influences of the lead-wires and decreases the wires' number.The principle and the constitution of the circuit are introduced.And the circuit's performances are demonstrated by a series of experiments.The linearity error is small and the stability is good.