静力试验应变测量中三线制转两线制的算法研究

摘要

Two methods of strain measurement in static test, two-wire and three-wire were introduced. We also discuss the necessity and feasibility of the transformation from two-wire to three-wire according to the character in aerospace static test, analyze the accuracy of bridge output and bridge strain. For errors caused by each influencing factor, we find the reason in theory and obtain the strain calculation formula. After calibrating the device, a new formula is obtained and a correction coefficient is fitted according to the calibration results. Then we calibrate the new device using the new algorithm, the calibration results meet the accuracy requested. At last, we apply the new algorithm into static test and the algorithm has been proved to be effective.%　　简单分析了静力试验应变测量中两线制和三线制两种测量方式。根据航天系统静力试验的特点，探讨将三线制设备改装为两线制设备的必要性和可行性。综合分析了新设备中各个影响因子对桥路输出电压和应变精度的影响，针对各个因素引起的误差，从理论上分析误差产生的原因并进行验证，得到了应变的理论计算公式。运用该公式对新设备进行标定，根据标定结果拟合出修正系数。根据由修正系数与理论计算公式组成的新算法对新系统重新进行标定，标定结果符合设备要求的精度。将新系统应用于实际的静力试验，获得了很好的效果，证明了新算法的正确性。