Abstract Real-time estimation of snow types and depth on a runway with stand-off sensing is essential for safe and efficient aircraft operations. Comprehensively identifying grain size, liquid water content (LWC), density and thickness is necessary for estimating the snow types and depth. However, off-the-shelf snow observation sensors are generally only optimized for one property of snow. In this study, we develop a light-scattering sensor consisting of lasers and image sensors, to obtain light-scattering images for comprehensively measuring the properties of snow. As a proof of concept demonstration, we measure snow samples with different grain size distribution, volumetric LWC, density and thickness, and obtain the relationship between the characteristics of snow and the optical scattering properties. For example, scattering intensity of the obtained image decreases as the grain size or volumetric LWC increases, and scattering area increases as the snow thickness increases. Additionally, given that multiple parameters can be extracted from a two-dimensional scattering image as well as with a different wavelength, by utilizing our sensor, we can simultaneously classify two properties of snow (e.g., grain size distribution and volumetric liquid water content, or density and thickness) on a scatter plot by extracting two indices from the obtained images. Our stand-off sensing technique shows great promise for improving safety and efficiency in aircraft operations during winter.

中文翻译：

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用于监测雪特性的光散射传感器

摘要 使用防区外感应实时估计跑道上的积雪类型和深度对于安全高效的飞机运行至关重要。综合识别颗粒大小、液态水含量（LWC）、密度和厚度是估算积雪类型和深度的必要条件。然而，现成的雪观测传感器通常仅针对雪的一种特性进行优化。在这项研究中，我们开发了一种由激光和图像传感器组成的光散射传感器，以获得用于综合测量雪特性的光散射图像。作为概念演示的证明，我们测量了具有不同粒度分布、体积 LWC、密度和厚度的雪样，并获得了雪的特性与光学散射特性之间的关系。例如，获得的图像的散射强度随着颗粒尺寸或体积 LWC 的增加而减小，并且散射面积随着雪厚度的增加而增加。此外，鉴于可以从二维散射图像以及不同波长中提取多个参数，通过利用我们的传感器，我们可以同时对雪的两个属性进行分类（例如，粒度分布和体积液态水含量，或密度和厚度）通过从获得的图像中提取两个指数来绘制散点图。我们的防区外传感技术在提高冬季飞机运行的安全性和效率方面显示出巨大的希望。鉴于可以从二维散射图像以及不同波长中提取多个参数，通过利用我们的传感器，我们可以同时对雪的两个属性进行分类（例如，粒度分布和体积液态水含量，或密度和通过从获得的图像中提取两个指数，散点图上的厚度）。我们的防区外传感技术在提高冬季飞机操作的安全性和效率方面显示出巨大的希望。鉴于可以从二维散射图像以及不同波长中提取多个参数，通过利用我们的传感器，我们可以同时对雪的两个属性进行分类（例如，粒度分布和体积液态水含量，或密度和通过从获得的图像中提取两个指数，散点图上的厚度）。我们的防区外传感技术在提高冬季飞机操作的安全性和效率方面显示出巨大的希望。