单轴旋转式光纤捷联惯导系统定位精度分析

Position accuracy analysis for single-axis rotary FSINS

为了方便地对单轴旋转式光纤捷联惯导系统的定位精度进行评估,提出了定位误差调制度(PEMD)的概念,并给出了运用PEMD对单轴旋转式捷联惯导系统定位精度进行评估的方法。对于长时间工作的惯导系统,通常情况下用经度误差来衡量系统整体的定位误差,推导了单轴旋转式捷联惯导系统PEMD的计算方法。针对不同地理位置的惯导系统调制效果进行了仿真分析,仿真结果与PEMD推算结果一致。结果表明,系统的调制效果与地理位置有关,纬度越低系统调制效果越好。最后运用实验室自行研制的光纤陀螺捷联惯导系统进行了静态实验和旋转调制实验,对PEMD估计定位误差结果的有效性进行了验证。实验表明:PEMD是一种准确、有效的旋转式捷联惯导系统定位精度分析方法。

In order to evaluate the position accuracy of single-axis rotary fiber strapdown inertial navigation system （FSINS） conveniently,the paper proposes the concept of position error modulation degree （PEMD） and provides the position accuracy evaluating method of single-axis rotation FSINS using the PEMD.For the long-time working inertial navigation system （INS）,the longitude error is adopted to evaluate the system overall position error; and the calculation method of the PEMD for single-axis rotary INS is deduced.The modulation effects of the INS in different geographic locations were analyzed in simulation,and the simulation results are consistent with the calculation results of the PEMD.The PEMD theory and simulation results show that the system modulation effect is related to geographic location; and the lower the latitude is,the better the modulation effect is.Finally,the static experiment and rotary modulation experiment were conducted using the FSINS developed in our laboratory,which verify the effectiveness of using PEMD to evaluate position error.Experiment results indicate that PEMD is an accurate,effective position accuracy analysis method for rotary SINS.