AvaRange: Particle Tracking in Snow Avalanches

雪崩等重力物质流的破坏性潜力对山区有很大的社会经济影响。我们目前对颗粒水平上的流动动力学的理解主要是基于实验室实验和计算机模拟。雪崩的测量技术通常包括非侵入性的外部可观测特性或侵入性流动-障碍物相互作用。一种合适的非侵入性流动测量方法，允许评估雪和颗粒特性(如温度、密度、大小或形状)对分离、相分离和最终流动等过程的影响，目前还缺乏一种合适的非侵入性流动测量方法。AvaRange项目旨在通过利用惯性传感器和无线测距领域的技术进步来检查雪崩的内部流动行为来弥合这一差距。具有通信和传感功能的嵌入式系统将用于实时测量。传感器配备了坚固的外壳并放置在释放区域，将能够随着雪崩移动。惯性导航提供每个传感器的局部运动信息，无线电测距方法允许多个传感器系统随着时间的推移进行通信和跟踪它们的距离。总而言之，这些方法是开发新的重力质量流流动测量方法的基础，这种方法允许跟踪雪崩中的粒子运动。实验可行性研究和对现有运动分析算法的检查表明，最先进的解决方案还不能做到这一点。AvaRange系统将是第一个在真实世界雪崩场景中高精度收集流动数据的系统方法。总体而言，AvaRange在了解雪崩的内部动态过程和流动流动性方面具有重大突破的潜力，这些过程和流动流动性决定了流动、停止和跳出行为以及冲击压力。有关粒子轨迹的详细信息将有助于雪崩流动模型的开发，这是雪崩模拟和危险地图应用程序的组成部分。恶劣的实验环境需要廉价、耐用但高精度的传感器组合，以及在雪地中强大的无线电传输能力。这些传感器也将对项目范围以外的各种不同的引力物质流感兴趣。了解雪崩中的颗粒传输和各自的流动轨迹对于预测滑雪者埋葬地点或碎片物质的运输及其可能的影响位置具有很高的相关性。增加对造粒和分离过程的了解将进一步有利于雪崩安全设备的设计。

The destructive potential of gravitational mass flows, such as snow avalanches, has a large socio-economic impact in mountainous regions. Our current understanding of flow dynamics on a particle level is mostly based on laboratory experiments and computer simulations. Measurement techniques of snow avalanches usually involve either non-invasive externally observable characteristics or invasive flow-obstacle interactions. An appropriate non-invasive in-flow measurement method, that allows to assess the influence of snow and particle properties, such as temperature, density, size, or shape, on processes like segregation, phase separation, and eventually flow mobility, is missing.The project AvaRange aims at bridging this gap by making use of technical advances in the fields of inertial sensors and wireless ranging to examine the internal flow behavior of avalanches. Embedded systems with communication and sensing capabilities will be used for real-time measurements. Equipped with robust housings and placed in release areas, the sensors will be able to move with the avalanche. Inertial navigation provides information on the local motion of each sensor and radio ranging methods allow multiple sensor systems to communicate and track their distances over time. Together, these approaches are the basis to develop novel in-flow measurement methods for gravitational mass flows, which allow to track particle motion within an avalanche. Experimental feasibility studies and examinations of existing motion analysis algorithms show that state of the art solutions are not yet able to do so. The AvaRange system will be the first systematic approach to collect in-flow data with high precision in real-world avalanche scenarios.Overall, AvaRange has the potential for major breakthroughs in the understanding of internal dynamic processes and flow mobility of avalanches, which determine flow, stopping, and run-out behavior as well as impact pressures. Detailed information on particle trajectories will contribute to the development of avalanche flow models, which are an integral part of avalanche simulations and hazard mapping applications. The harsh experimental environments demand inexpensive, durable, yet highly accurate sensor combinations with robust radio transmission in snow. These sensors will also be of interest for all kinds of different gravitational mass flows beyond the scope of the project. The understanding of particle transport and the respective flow trajectories in avalanches is highly relevant, e.g., for skier burial location prediction or transport of debris material and their possible impact location. An increased understanding of granulation and segregation processes will further be beneficial to design of avalanche safety equipment.