斜装液浮陀螺一次项漂移系数系统级分离算法

System separation algorithm of acceleration-sensitive drift coefficients of skewed-installation liquid floated gyro

摘要:

在免拆卸条件下,为实现实时监测倾斜安装在惯性测量单元(IMU, inertial measurement unit)中的液浮陀螺一次项漂移系数DI、Ds,提出一种利用惯性测量单元标定参数解算液浮陀螺一次项漂移系数的系统级分离算法．通过对液浮陀螺结构和斜装原理的分析,给出了液浮陀螺单表和系统的误差模型,并基于误差模型和已经获取的斜装IMU的误差参数,设计了液浮陀螺一次项漂移系数的系统级分离算法,该算法不需要设计复杂的倾斜标定工装,同时免去了液浮陀螺从惯性测量单元上拆卸的麻烦,减少了误差积累,参数的分离精度高、残差小,与单表一次项漂移系数分离结果的极差优于1.301×10-3(°)·(h·g₀)-1,完全满足工程应用中高精度惯性测量单元对液浮陀螺一次项漂移系数的分离精度要求．

Abstract:

To achieve monitoring acceleration-sensitive drift coefficients DID_s of the skewed-installation liquid floated gyroscope in IMU(inertial measurement unit) on the condition of free disassemble, a system level separation algorithm using calibration parameters of inertial measurement unit is put forward. By the analysis of structure and skew installation principle of liquid floated gyroscope, the paper gives the liquid floated gyroscope and its system’s error models. Then based on error models and ever-obtained error parameters of skew inertial measurement unit,the system level separation algorithm of acceleration-sensitive drift coefficients is designed. It is unnecessary to design complex calibration tool when using this algorithm, and also without removing liquid floated gyroscopes from inertial measurement unit, these improvements can reduce error accumulations, so that the precision of parameters’s separation is high, and the residual error is small. The deviation between the single gyro separation algorithm and system level separation algorithm is smaller than 1.301×10-3(°)·(h·g₀)-1, which fully meets the requirements of high precision inertial measurement unit to acceleration-sensitive drift coefficients of liquid floated gyroscopes in engineering application.