基于振动载荷的灵敏度标定方法研究与试验验证

Load Calibration Method and Verification Based on Vibration Test

为了获取舱段载荷和应变之间的关系,进而获得运载火箭在飞行过程中的截面动态载荷,基于应变测量原理设计了一种基于振动载荷的灵敏度标定方法。给出了载荷测量的原理,推导了动态轴向力的频响特性,建立了载荷计算模型,给出了振动标定试验和验证试验的设计方法。设计了一个典型的光筒薄壁舱段,开展了振动载荷灵敏度标定试验,获得了舱段的轴向力、弯矩载荷灵敏度系数。随后开展了验证试验,结果表明,计算与实测载荷之间的均方根误差不超过5%,该方法具有可行性和较高的测量精度,可为后续的运载火箭飞行载荷测量提供一种新的方案。

In order to obtain the relationship of load and strain for a compartment,thus calculate the in-flight dynamic load for launch vehicles,a new load calibration method is invented.The method is based on strain measurement principle and uses dynamic load as the input.Load measurement model is established,and frequency response characteristic analysis of the measurement about dynamic force is deduced.Measurement system arrangement method is presented and calibration test and verification test are designed.A typical thin compartment is designed,with which the calibration test is carried out.Using the data from the test,load coefficients between load and strain are obtained.The verification test is carried out.Comparison between the load which is measured using load sensors,and the load which is calculated using the load measurement model,is made.The two are very close,with an average square tolerance less than 5%.This is a demonstration of the feasibility and validity of the method.The load calibration method provides a new way of load measurement,and can be used in many areas.