基于双目标识别和准直数学模型改进的光路自动准直方法

An Optical Path Automatic Alignment Method Based on Dual-target Recognition and Improved Alignment Mathematical Model

针对原有大型激光装置在双光学目标条件下无法实现光路对接准直的缺点,本文提出了一种基于双目标识别和准直数学模型改进的光路自动准直方法,主要从双目标识别算法实现和多光路、双目标准直数字模型的构建两个方面进行优化。首先,提出基于圆拟合的双光学目标识别图像处理算法,实现了双光学目标的识别,为光路对接准直的成功提供保障;其次,构建新的多光路、双目标自动准直数学模型,为光路准直中各个准直参数的标定和计算提供指导;最后,优化准直流程的调度,对多个光路进行并行准直,提高光路对接准直流程的效率。实验结果表明:本文提出的基于圆拟合的双光学目标识别算法实现了光路对接准直流程中的模拟光目标和主激光目标的识别,识别误差精度小于3个像素,处理时间小于1 s,满足了大型激光装置光路对接准直过程对于精度和效率的要求。本文构建的基于多光路、双目标自动准直数学模型对于光路对接准直流程的成功具有指导意义。

The high-power laser device needs to complete optical path self-alignment,analog optical alignment and optical docking alignment before physical experiment starting.With the deepening of physical experiments,the optical docking alignment process of high-power laser device encounters some new problems.First of all,the number of optical targets has changed.In the previous optical docking alignment process,alignment task was performed with the analog laser source turned off.There was only one main laser target in the docking alignment image.Now,in order to reduce the influence of the drift alignment accuracy of the main laser target,the analog laser source is no longer turned off in the alignment process,which means an optical path alignment image contains both an analog laser target and a main laser target.Moreover,optical docking alignment mathematical model has changed,too.In the original highpower laser device,the automatic alignment of 8-path beams adopted the same unit alignment model.The original mathematical model has only one optical target in alignment image instead of multiple optical targets.And the original mathematical model is only for a single-path beam,and the parameter information of multi-path beams is not reflected in the mathematical model.Finally,the docking alignment process of high-power laser was executed in serial in the past,which greatly affected the alignment efficiency.In order to solve the above problems,this paper makes improvements from the following three aspects.For the first problem,according to the characteristics of different optical targets in optical docking alignment images,a dual-optical target recognition algorithm based on circle fitting algorithm is proposed.This algorithm uses the edge pixels of optical objects to perform circle fitting,then calculates their circle fitting ratio.Different optical targets can be recognized by comparing their circle fitting ratio.However,in some special situations,the difference between the circle fitting ratio of the analog laser target and the main laser target is very slight.It is not effective to recognize the dual targets only by the circle fitting ratio.Therefore,a new parameter,based on the circle fitting coefficient,BLOB region number is added as a supplement to the circle fitting coefficient to jointly determine the final target recognition result.For the second problem,this paper build a new automatic alignment mathematical model based on multi-optical path and dual-target.The new mathematical model embodies the characteristics of optical targets well,and improves convergence condition,which could judge whether the distance between the main laser center and target position is less than the given error threshold.For the last problem,this paper improves the efficiency of optical docking alignment by parallel alignment multiple optical paths.The experimental results show that the dual-optical target recognition algorithm proposed in this paper based on circle fitting can recognize analog laser target and main laser target well.Besides,the recognition error accuracy is less than 3 pixels,and the processing time is less than 1 second,which meets the accuracy and efficiency requirements of optical docking alignment of the high-power laser device.Simultaneously,the automatic alignment mathematical model constructed in this paper based on multiple optical paths and dual targets has great significance for the success of optical docking alignment.