Long term stability of a novel strain gage conditioner based on the direct resistance method

摘要

It is over fifteen years now since the Direct Resistance Measurement method (DRM) has been proposed [1] as an alternative methodology to condition the output signal of the ubiquitous electrical resistance strain gage. In short, the DRM simply uses the direct measurement of the variation of the voltage drop across the changing resistance of a strain gage, by driving a constant current through it. The DRM method was metrologically examined by using commercially available instrumentation and the results obtained showed the viability of the proposed method for the usual experimental analysis [2-7]. Moreover, from a thorough comparison with the traditional Wheatstone Bridge (WB) it emerged that the DRM, in spite of being a simpler scheme, still contains the benefit of the well known compensating properties of the WB.