AGS-PRF: Improved In Situ Thermodynamic Sampling of Severe Storms with Unmanned Aircraft Systems Through Improved Wind Estimation and Energy Harvesting

超级单体雷暴中龙卷风起源的研究进展在很大程度上依赖于对超级单体内部原位热力学特性的精确测量。VORTEX2项目的一个试点项目证明了使用小型无人机系统（UAS）进行定向采样的能力，首次实现了由UAS对超级单体雷暴后侧翼阵风锋和与后侧翼下降气流相关的气团的采样。尽管取得了这样的成功，但在这样一个系统能够在所需的体积和时间范围内定期返回具有科学价值和足够精确的测量数据之前，还有很多工作要做。这项工作将为强风暴的有效现场采样提供下一步所需的条件。将对采样风暴特征的技术进行调查，包括改进风估计和使用风能收集来扩展无人驾驶飞机采样任务。这项研究的成果将与科罗拉多大学博尔德分校和内布拉斯加大学林肯分校目前的工作相结合，以构建用于气象采样的下一代无人机系统。这些联合努力将通过提供一种可部署的仪器系统，使小型廉价飞机能够“常规”进入这些风暴，对复杂大气现象的热力学特性进行有针对性的采样，从而改变严重风暴的研究。对复杂大气现象进行定向原位测量的新能力具有潜在的革命性。贡献包括:1。从目前用于小型无人驾驶飞机系统的可用传感器的精度出发，对风速和加速度估计的当前方法进行了表征。开发一种混合风状态估计器，将机载传感器测量结果与通过综合多普勒雷达观测得到的结果融合。3 .利用静态飙升、动态飙升和从阵风中提取能量的算法，估计可以从强风暴中提取的能量量。构建一个混合控制器，以利用在强风暴中可用的能量，要么遵循特定的采样模式，要么通过徘徊延长任务续航时间。更广泛的影响这项研究跨越了两个不同的学科，需要三个不同机构的合作。它将为下一代系统提供关键组件，用于精确测量强风暴的热力学特性。这些测量将有利于建模和预报，使人们能够更好地了解风暴，并建立更好的预测系统，最终挽救生命。

Advancement of research into the origins of tornadoes in supercell thunderstorms is heavily dependent upon the ability to accurately measure the in-situ thermodynamic properties within supercells. A pilot program during the VORTEX2 project proved the ability to conduct directed sampling using small unmanned aircraft systems (UAS), achieving the first ever sampling of the rear flank gust front and airmass associated with the rear flank downdraft of a supercell thunderstorm by a UAS. Despite this success, much work remains before such a system will be able to regularly return scientifically valuable and sufficiently accurate measurements over the volume and time span needed.This work will provide the next step needed for effective in-situ sampling of severe storms. An investigation into the techniques for sampling storm features will be performed, including improved wind estimation and the use of wind energy harvesting to extend unmanned aircraft sampling missions. The product of this fellowship will be combined with current efforts at the University of Colorado Boulder and University of Nebraska-Lincoln to construct a next generation UAS for meteorological sampling. These combined efforts will transform severe storms research by providing a deployable instrument system for "routine" access into these storms with small, inexpensive aircraft capable of targeted sampling of the thermodynamic properties of complex atmospheric phenomena.Intellectual MeritThe new capabilities for targeted in-situ measurements in complex atmospheric phenomena are potentially revolutionary. Contributions include:1. Characterization of current methods for wind velocity and acceleration estimation, with respect to the accuracy of currently available sensors for small unmanned aircraft systems.2. Development of a hybrid wind state estimator to fuse on-board sensor measurements from those obtained through the synthesis of Doppler radar observations.3. Estimation of the amount of energy that can be extracted from severe storms employing algorithms for static soaring, dynamic soaring, and energy extraction from gusts.4. Construction of a hybrid controller to take advantage of the energy available in severe storms to either follow a specific sampling pattern, or extend mission endurance through loitering.Broader ImpactsThis research spans two distinct disciplines, and requires the collaboration of three different institutions. It will provide a critical component for the next-generation system designed to accurately measure the thermodynamic properties of severe storms. These measurements will benefit both modeling and forecasting, allowing for greater understanding of the storms, and better prediction systems which will ultimately save lives.