A novel methodology to simultaneously measure strain and temperature by means of an electrical resistance strain gauge powered by an ac signal and connected to a strain indicator by means of thermocouple wires is proposed. The experimental validation of the viability of this method is conducted by means of a purely electrical simulation of both strain and temperature signals, respectively from -2000 to 2000 mum m(-1) and -250 to 230 degreesC. The results obtained showed that strain measurement is affected by an error always less than +/-2 mum m(-1) for the whole range of simulated strains, while the error in temperature evaluation is always less than 0.6 degreesC. The effect of cross-talk between the two signals was determined to be insignificant.
Cappa, P., Marinozzi, F., Sciuto, S.A. (2001). A novel method for the simultaneous measurement of temperature and strain using a three wire connection. MEASUREMENT SCIENCE & TECHNOLOGY, 12 (4), 502-506 [10.1088/0957-0233/12/4/315].