激光测速仪速度算法改进研究

Study on the Improved Algorithm of Laser Screen Measuring System

弹丸和破片速度测量是武器弹药毁伤威力性能评估中最重要的指标之一,然而多数情况下得到的信号存在信噪比低、目标多、难以识别等困难,降低了速度测试的准确性。提出了基于互相关理论的目标速度测量方法和多发弹丸信号匹配识别方法。推导了利用两激光光幕探测系统输出信号的互相关函数计算目标速度的理论公式,并采用皮尔逊相关系数来描述多个输出信号的相似程度。通过Matlab仿真和5连发实际测试,结果表明:互相关算法可进行目标速度分析,采用互相关算法可对目标经过两激光光幕产生的连发弹丸信号进行匹配识别;实测匹配信号的相似度在0.94以上,测速误差最大为0.39%。

The velocity measurement of projectile and fragment is one of the most important parameters in weapon performance evaluation.In most cases,however,the obtained signal has low signal-to-noise ratio,multi object and difficult recognition.These issues reduce the accuracy of the speed test.The method of measuring the projectile velocity and the matching method of the multiple projectiles based on the cross-correlation theory are proposed in this paper.The mathematical expression of correlation function for calculating the velocity of projectile with the output signal of two laser screens detecting system is derived and the Pearson correlation coefficient is used to describe the similarity degree of the target signals.Through Matlab simulation and 5 repeating projectile of actual test,the results show that the correlation method can be used in the projectile velocity measurement,and the mutual correlation number method can be used to identify the signal of repeating projectile.The similarity of matching measured projectile signal is more than 0.94,and the maximum error of velocity test is up to 0.39%.