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Applications Note 1-4:The measurement of the output of a nonlinear sensor may be linearized by measuringthe output of the sensor at 0%, 20%, 40%, 60%, 80%, and 100% of the fullscaleinput of the sensor (Figure 1-3). This data may be used to form a piece-wiselinear curve that closely approximates the nonlinear output function but willrequire significant computational time for each data point collected and will, therefore,limit the maximum practical output bandwidth.FIGURE 1-3. Piece-wise LinearizationM4M5M2M3OutputY5Y4Y3Y2Y1M1Where:Output = Mi (Input) + Yi(For each of the appropriatecurve sections)0% 20% 40% 60% 80% 100%InputPiece-wise linearization of a nonlinear lineThe measurement of the output function used for piece-wise data linearization canalso be used as an input to a polynomial curve-fit program wherein the measurementsystem either computes the curve-fit in real time for each data point collectedor creates a Òlook-upÓ map of output versus input parameters in memory. The useof an internal look-up map of the sensor output with respect to its input will greatlyincrease the potential output frequency response, as simple decision algorithmsmay be used rather than complex real time computations. The implementation ofThe Art of Practical and Precise Strain Based Measurement 2nd Edition © 1999 CHAPTER 1-13