ERI: Drones-Enabled Active Sensing System (DEASS) for Detection of Subsurface Defects in Civil Infrastructure through Synchronized Drone Swarming and Thermal Imaging

该奖项全部或部分由《2021年美国救援计划法案》（公法117-2）资助。该工程研究启动（ERI）项目将探索一种由一对无人机携带的主动热成像系统，一架（领导）用于热成像，另一架（跟随）用于主动加热（例如，微波），以便在没有gps的环境中（例如，桥面下面）对下一代民用基础设施进行地下缺陷检测。由于其有限的有效载荷和电池时间，单个无人机无法支持主动传感所需的额外有效载荷及其相关配件。因此，引入了两个leader-follower无人机的概念。该合同支持通过同步无人机蜂群和热成像技术开发无人机主动传感系统的基础研究。这项新技术将改变目前被动的表面劣化检测实践，即受阳光条件变化的影响，转变为对地下劣化的主动热成像检测，如钢筋混凝土结构中的分层和水平裂缝。除了基础设施检查和维护之外，新技术还将影响协同机器人群和主动感知的多个前沿领域，例如交互式制造和医疗保健，以及科学和工程领域的学术团体。技术和研究成果将通过全国讲习班转移到工程专业人员手中。无人机主动传感系统将通过软件/硬件在环模拟和实验测试进行研究。本研究将克服两个技术挑战：(1)以一种节能的策略同步无人机蜂群和热成像；(2)利用分布在主从无人机平台上的热源实现新的热成像可探测性，以刺激主动成像中地下缺陷的出现。它将为机器人协同蜂群和主动传感的多前沿研究奠定基础。首先，基于三维立体视觉和势场算法，在gps拒绝环境下协同主动感知和检测地下缺陷过程中，开发具有视觉相对导航和避碰的无人机群leader-follower编队新策略。其次，通过优化微波激励（能量源、频率和持续时间）和传感协议（测量灵敏度、帧率和时间窗），建立微波加热混凝土甲板主动传感的最优特性。第三，它将开发一种方法来评估和改进协同无人机群编队和标记固体甲板混凝土桥梁缺陷主动热成像的性能和潜在的现场基础设施检查。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).This Engineering Research Initiation (ERI) project will explore an active thermal imaging system carried by a pair of drones, one (leader) for thermal imaging and the other (follower) for active heating (e.g., microwave), to enable subsurface defect detection in the next-generation inspection of civil infrastructure in a GPS-denied environment (e.g., underneath bridge decks). Due to its limited payload and battery time, a single drone cannot support additional payload and its associated accessories required for active sensing. The concept of two leader-follower drones is thus introduced. This award supports fundamental research for the development of a drones-enabled active sensing system through synchronized drone swarming and thermal imaging. The new technique will transform the current passive surface deterioration inspection practice, which is subject to the change in sunlight conditions, into an active thermal imaging inspection for subsurface condition deterioration, such as delamination and horizontal cracks in reinforced concrete structures. In addition to infrastructure inspection and maintenance, the new technique will impact multiple frontiers with cooperative robot swarming and active sensing, such as interactive manufacturing and healthcare, and academic communities in science and engineering. The technique and research results will be transferred into the hands of engineering professionals through a national workshop.The drones-enabled active sensing system will be investigated via software/hardware-in-the-loop simulations and experimental tests. This research will overcome two technical challenges: (1) to synchronize drone swarming and thermal imaging in an energy-efficient strategy and (2) to enable new thermal imaging detectability with a heat source distributed on a leader-follower drone platform to stimulate the appearance of subsurface defects in active imaging. It will lay a foundation on cooperative robot swarming and active sensing research in multiple frontiers. First, it will develop a new strategy of leader-follower formation for drone swarming with visual relative navigation and collision avoidance based on a three-dimensional stereo vision and potential field algorithm during cooperative active sensing and inspection of subsurface defects in a GPS-denied environment. Second, it will establish optimal characteristics of active sensing of microwave heated concrete decks with optimized microwave excitations (energy source, frequency and duration) and sensing protocols (measurement sensitivity, frame rate and time window). Third, it will develop a method to evaluate and improve the performance of cooperative drone swarm formation and active thermal imaging of defects in a markup solid deck concrete bridge and a potential field infrastructure inspection.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.