针对高g值加速度计动态线性度标定问题,对基于霍普金森杆的标定系统所存在的技术问题进行了研究.为实现双子弹同步撞击标定杆从而产生标定所需的叠加信号,提出了单一炮管同步发射双子弹的方法,利用防止内外2发子弹相互滑动的紧固措施,有效地实现了双子弹撞击的同步性.运用有限元方法系统研究了子弹几何形状、材料、冲击速度和整形器的使用对高g值加速度计标定中的激励脉冲波形的影响机制,进而总结出双子弹标定系统子弹选择和波形控制方法.结果表明:在双子弹标定系统中,为了对加速度计进行某一频带上的动态线性度标定,可通过改变双子弹相对截面积或冲击速度的方式改变g值,通过改变子弹材料的方式改变标定频带.最后,利用提出的单炮管双子弹霍普金森杆标定系统对988-1198型加速度计的动态线性度进行实测,效果良好,证明了该方法的可行性.%The key problems in the dynamic linearity calibration of high-g accelerometers using Hopkinson bar system are studied. A single gun barrel system is proposed to achieve the synchronous impacts of two projectiles in the dynamic linearity calibration of accelerometers, in which the two projectiles are fastened by small-sized screws near their rear ends. The influences of geometry and material of projectile, impact velocity and pulse shaper on the excitation signals are investigated by using numerical method. It is found that that the amplitude of excitation pulse could be changed by adjusting the relative area of two projectiles and impact velocity. A certain frequency bandwidth could be achieved by using the projectile made from proper material. The single-barrel system is employed to calibrate the dynamic linearity of 988-1198 accelerometers, which proves the practicability of the proposed calibration system.
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