Development of a floating element photoelastic force balance

Abstract We present a floating element force balance design that uses an optical measurement of the using photoelastic stress analysis. The sensing consists pins embedded in polyurethane pads, which generate internal when is loaded observed via transmission polariscope. A series known loads and their corresponding fringe patterns allow calibration matrix to be derived polynomial model solved by least squares regression. Finite analysis (FEA) simulation carried out validate proposed method. then measured lift curve NACA0015 wing at low speed. comparison commercial, 6-axis strain-gauge load cell showed typical differences less than 6 $$\%$$ % . This approach enables accurate measurements with inexpensive simple components inside sensor. work demonstrates simple, inexpensive, sensitive transducer.