高g 值加速度校准激励脉冲的横向激光干涉测量方法

为了准确测量高g值加速度传感器校准激励脉冲的幅值和持续时间,研究了基于激光多普勒的加速度脉冲测量方法。在分析激光多普勒原理的基础上,设计了以光栅为合作目标的激光测速仪;针对干涉仪输出的存在零点漂移的多普勒信号,提出了基于多项式拟合和希尔伯特变换的局部均值分解法;利用该方法对实测多普勒信号进行了解算,得到了激励加速度脉冲;分析了由干涉仪及其合作目标引起的加速度脉冲的幅值和脉宽测量不确定度。实测数据表明:该方法在包含因子k=2时幅值测量的扩展不确定度为U=3%,脉宽测量的扩展不确定度为U=4.8%。测量精度符合ISO16063-13(2001)规定的指标。

Measurement of exciting pulse for calibration of high- g accelerometer using lateral laser interferometer

To accurately measure the amplitude and duration of exciting pulse for calibration of a high-g accelerometer, the measurement method of the exciting pulse was studied in this paper. Based on the analysis of the principle of Laser Doppler, a grating laser velocimeter was designed. A local mean decomposition algorithm based on polynomial fitting and Hilbert transform was put forward to process the Doppler signal with zero shift. The acceleration pulse was calculated using the above algorithm and the uncertainties of measurement of the amplitude and duration were analyzed and calculated. The expanded uncertainties verified by experiments are 3% for the amplitude and 4.8% for the duration with a coverage factor k =2. This method is effective for pulse measurement and the measurement precision met the requirements of ISO16063-13(2001).