Critical civil and military structures require 'smart' sensors in order to report their strain histories; this can help to insure safe operation after exposure to potentially damaging loads. A passive resetable peak strain detector was developed by modifying the mechanics of a differential variable reluctance transducer. The peak strain detector was attached to an aluminum test beam along with a bonded resistance strain gauge and a standard DVRT. Strain measurements were recorded during cyclic beam deflections. DVRT output was compared to the bonded resistance strain gauge output, yielding correlation coefficients ranging from 0.9989 to 0.9998 for al teste, including re-attachment of the DVRT to the specimen. Peak bending strains were obtained by the modified peak detect DVRT to the specimen. Peak bending strains were obtained by the modified peak detect DVRT and this was compared to the peak bending strains as measured by the bonded strain gauge. The peak detect DVRT demonstrated an accuracy of approximately $POM 5 percent over a peak range of 2000 to 2800 microstrain.
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