Algorithm Study of Eliminating Calculation Errors in Large Strain Measurement With Strain Gauges
Yang Xiao-feng · Journal of Experimental Mechanics · 2008
There is no simple linear relationship between the gauge's strain and the circuit voltage output in strain measurement with strain gauges,especially in large strain measurement.In this paper,a modified algorithm is proposed to improve the accuracy of strain obtained from the voltage output measurement.The strain is calculated from a nonlinear relationship between the voltage and the strain rather than a linear simplification.The proposed method of strain calculation is suitable for both large and small strain measurements using a quarter bridge,and is validated by experimental tests.Moreover,the corrections of different sensitivity factors of strain gauges and the lead wire resistance are considered.It is also very easy to implement as a software form and widely used in scientific tests and engineering applications.