Development Of Temperature Compensated Semiconductor Strain Gauge

The hypersonic wind tunnel is the most basic and important ground simulation equipment in modern aerodynamic research,and is widely used in research and development in aerospace,military weapons and other fields.Strain gauges are the core component of the strain gauge balance used to detect the force of the model in the hypersonic wind tunnel experiment.Nowadays,with the rapid development of hypersonic technology,the traditional metal foil strain gauge has been unable to meet the development requirements due to its low sensitivity.Therefore,it is necessary to develop high-precision strain gaugesThe diffused semiconductor strain gauge is a kind of sensor based on piezoresistive effect,which has the advantages of high sensitivity,large linearity,small hysteresis,small creep,small volume and low power consumption.However,the sensitivity of semiconductor strain gauge to temperature limits its application in hypersonic wind tunnel experiments.Therefore,in order to make use of the excellent characteristics of semiconductor strain gauge,this paper developed a high-precision semiconductor strain gauge with temperature compensation.(1)Based on the theoretical analysis,the design of the temperature-compensated semiconductor strain gauge was completed from the aspects of material selection,resistance design and varistor layout.The simulated results showed that the designed temperature compensation strain gauge based on silicon material and serpentine layout has the characteristics of high sensitivity,high linearity,and good temperature compensation.(2)The designed temperature-compensated semiconductor strain gauge was manufactured using advanced integrated circuit technology.The resistance test showed that the relative standard deviation between the resistances of the semiconductor strain gauges was less than 1.24%,which has good consistency.In addition,the sensitivity and linearity of the semiconductor strain gauge could reach 71 and-0.026% FS,respectively.(3)The influence of adhesives and samples on the performance of semiconductor strain gauges was studied,and the temperature compensation of semiconductor strain gauge by series NTC resistance was theoretically proposed.Finally,the performance changes of semiconductor strain gauge before and after series NTC resistance were tested and compared.The results showed that the developed temperature-compensated semiconductor strain gauge has excellent performance,and the sensitivity remained within 50±1 in the temperature range of 20-80 ?.(4)The developed semiconductor strain gauge was successfully applied to the three-component bar-shaped strain gauge balanc,and the static calibration results showed that the accuracy and repeatability of each component of the three-component bar-shaped strain gauge balanc were better than 0.28% and 0.15%,respectively.The static calibration results show that the three-component bar-shaped strain gauge balance can effectively measure the aerodynamic load of the aircraft model.