斜端面Hopkinson杆校准多维高g值加速度计方法研究

Calibrating Multi-dimensional High-g Acceleration with Bevel End Hopkinson Bar

为了对多维高g值加速度计灵敏度系数进行校准,提出一种斜端面Hopkinson杆实现多维加速度计量脉冲方法。首先,通过ANSYS/LS-DYNA有限元软件分析了斜面角度和激励脉宽对斜面上质点波形的影响,定义杆端斜面部分沿杆轴向投影L与激励脉冲波长λ的比值为δ;其次,利用改进的斜端面Hopkinson杆对三轴加速度计中2个轴的灵敏度及交叉灵敏度系数进行同步校准,得到不同气压下灵敏度系数矩阵。研究结果表明:δ并不是决定斜面质点加速度波形的唯一参数,但对相同L的校准杆,δ值越小,斜面各质点加速度波形越趋于一致;因轴间耦合作用,双轴同步校准得到的各主轴灵敏度系数要小于单轴依次校准,且z轴方向激励(安装面法线方向)对y向(安装面切向)输出影响较大。

To calibrate the sensitivity coefficient of multi-dimensional high-g accelerometer,a method based on Hopkinson bar with a bevel end is proposed.Through ANSYS/LS-DYNA finite element software,the effect on the waveform of different particles on the slope is analyzed in detail based on the relationship between the slope angle and the width of acceleration pulse.And the ratio of the slope axial projection L to the excitation pulse wavelengthλis defined asδ.The result shows thatδis not the only parameter that determines the consis⁃tency of the acceleration waveform of the particles on the inclined surface.However,with the same L of the cali⁃bration bar,the smaller theδleads to more consistent acceleration waveform of each particle on the inclined plane.In the end,by using Hopkinson bar with a bevel end,the sensitivity coefficients and cross sensitivity coef⁃ficients of the two axes in the three-axis accelerometer are calibrated synchronously.Additionally,the sensitivity coefficient matrix is obtained.The sensitivity coefficient of each axis obtained by two axis synchronous calibra⁃tion is smaller than that of single axis calibration in turn due to the coupling effect between axes.Moreover,the excitation in the z-axis direction(normal direction of the mounting surface)has a greater impact on the y-direc⁃tion(tangential direction of the mounting surface).