基于累积误差效应的瞬变加注量融合算法

为提高火箭推进剂加注量的计量精度,在原系统单一的流量计基础上新增超声波流量计和高精度液位计,并对液位计进行液位-体积标定,使三路测量设备同时参与加注量计量.根据设备计量原理分析了三路加注量数据的变化特性和误差特性,并利用时域估计法和数据加窗法推导了各瞬变加注量误差信号的方差估计算法,给出了基于方差最小二乘意义下的最优加权融合结果.实际应用表明该融合算法可以有效地抑制累积误差的不断扩大,提供比原始数据精度更高的实时加注量数据.

Fusion algorithm for transient loading volume with accumulative error

In order to improve measuring accuracy of rocket propellant loading volume,an ultrasonic flowmeter and a high precision liquid-level meter were added to the original loading-system based on the single flowemeter.The relationship between the liquid-level and the volume was calibrated in advance.Thus,the loading volume was measured with three devices at the same time.Through analyzing the variation characteristic and error characteristic of the three measurement data,variance estimations of the three loading volume error were deduced respectively using time-domain estimation and data window,and the optimal weighted fusion algorithm was given using the least squares method.Practical application shows that the fusion algorithm is able to inhibit the expansion of accumulative error,offer more precise real-time loading volume data.