弹箭磁屏蔽效能仿真及分析

为了分析磁传感器的测量误差,建立了弹体静磁屏蔽效应数学模型,利用ANSYS软件进行弹体三维磁场仿真,分析了弹体相对磁导率、壁厚等自身因素对磁屏蔽系数的影响,仿真结果与理论计算结果一致。仿真研究并拟合出弹体磁屏蔽系数与弹体姿态角之间的关系。结果表明,当弹轴与磁场方向平行时,磁屏蔽系数最小,随着夹角的增大,磁屏蔽系数增大,当弹轴与磁场方向垂直时,磁屏蔽系数最大。建立了磁屏蔽椭球模型,提出直接获取软磁误差矩阵的方法,为磁传感器的误差校正提供了理论基础;给出了利用磁屏蔽椭球模型直接解算弹体相对于地磁矢量姿态角的方法,为磁传感器在弹上的应用提供了理论基础。

Simulation and Analysis for Magnetic Shielding Effectiveness of Projectile

In order to study the magnetic-sensor measuring errors,the magnetic shielding-effect model was established. The ANSYS software was applied to simulate the 3D magnetic-field of projectile. The influences of the relative permeability of projectile material and the thickness of projectile body on the magnetic shielding effectiveness were analyzed. The simulation results are consistent with theoretical calculation results. The effects of projectile attitude on the shielding effectiveness were investigated,and the relationship between them was derived. The shielding effect is minimum when the projectiles axis is aligned with the geomagnetic field direction,and the effect is maximum when they are perpendicular. The magnetic-shielding effectiveness ellipsoid model was built,and the way to obtain the soft-magnetic error-matrix was proposed. The result provides the theory foundation for the error correction of magnetic sensor. The way to calculate projectile attitude angles with respect to the geomagnetic field vector was given.