基于距离选通激光成像技术的水下目标三维成像方法研究

发布时间：2018-07-17 20:59

【摘要】：距离选通激光成像技术具有成熟的理论基础、较高的工程化程度以及较强的环境适应力,广泛应用于水下环境成像。因此将该技术应用于水下三维成像。有着很大的优势。本论文对基于水下距离选通激光成像技术的水下三维成像方法进行了研究。通过对距离选通成像系统成像范围内的回波强度分布进行了仿真模拟,分析了距离选通成像技术的成像特点,选择了图像点除法这一水下三维成像方法,并利用得到的成像范围内的回避强度分布,对经过图像点除处理后得到的新图像中像素灰度与对应的距离的关系曲线做了仿真计算。设计了空气中和水下的目标三维成像实验通过图像点除三维成像方法获得了目标的三维图像,计算了三维图像与实际目标几何尺寸的误差,并对该误差来源进行了分析,为进一步的提高重构精度提供了方向。实验证明:图像点除三维成像方法方法能够有效抑制了水下成像系统中存在的目标表面材质、水体衰减以及目标各点法线方向与入射激光脉冲方向夹角不同等因素对于三维成像造成的不良影响,同时仅需要从单一方向对目标进行两组成像,减少了所需图像采集的次数,简化了三维重构的过程。
[Abstract]:Range gated laser imaging technology is widely used in underwater environment imaging because of its mature theoretical foundation, high engineering degree and strong environmental adaptability. Therefore, this technique is applied to underwater three-dimensional imaging. Have a great advantage. In this paper, the underwater three-dimensional imaging method based on range-gated laser imaging technology is studied. The echo intensity distribution in range of range-gated imaging system is simulated, and the imaging characteristics of range-gated imaging technology are analyzed. Using the evasive intensity distribution in the imaging range, the curve of the relationship between the pixel gray and the corresponding distance in the new image obtained by the image dot division processing is simulated and calculated. In this paper, the 3D image of the target is obtained by the method of image dot division. The error between the 3D image and the actual object is calculated, and the source of the error is analyzed. It provides the direction for further improving the precision of reconstruction. Experimental results show that the method of image dot division 3D imaging can effectively suppress the surface material of the target in underwater imaging system. The water attenuation and the different angles between the normal direction of the target points and the direction of the incident laser pulse cause the adverse effects on the 3D imaging. At the same time, only two groups of images are needed from the single direction, which reduces the number of image acquisition required. The process of 3D reconstruction is simplified.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TP391.41;TN249

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