SBIR Phase I: Smart IoT System for Rapid Condition Assessment of Bridges under Sudden Events

这项小企业创新研究（SBIR）第一阶段项目将对铁路、民用基础设施和工程服务行业产生更广泛的影响，为工程公司和基础设施所有者提供加强公共安全的手段，同时显著降低桥梁基础设施监控成本和因突发事件导致的基础设施停机造成的收入损失。在美国的70多万座桥梁上，每年都会发生成千上万的突发事件，比如车辆撞击和超重车辆过桥。尽管它们有可能导致结构失效或隐性损伤，从而大大降低结构的使用寿命，但许多事件都没有被注意或报告。该项目将提供一种具有成本效益的无线解决方案，以近实时的方式检测、量化和报告民用基础设施上的突发事件。拟议的解决方案将用一个紧凑、易于部署的设备取代现有的三种类型的监控系统，其成本甚至是单个遗留系统的一小部分。快速状况评估能力将进一步减少交通中断，从而降低每日数百万美元的经济损失，并有可能使国家的交通基础设施更安全。该项目旨在开发智能物联网监测系统，以便在突发事件下快速评估民用基础设施的状态。有线系统对于大多数结构来说过于昂贵，特别是在偏远地区的桥梁，现有的无线解决方案采用占空比方法来降低功耗，无法实现突发事件检测所需的始终在线监控。该研究的目的是开发一种低成本的物联网系统，以保持始终在线的监控，以便在最小的功率预算下，在不牺牲数据保真度的情况下，不会错过事件，并且具有非常低的误报率。为此，将开发一种异步触发的同步数据采集方法，该方法使用高保真无线传感器，该传感器与可编程的基于事件的开关紧密耦合，能够始终工作。这种方法将使系统无限期地保持超低功耗运行，并在事件检测后迅速过渡到高保真度测量。独特的是，在多个传感器之间处理和拼接事件前后的数据，而无需先验同步。将进行实验来演示该系统。能够捕捉突发事件的发生，并近乎实时地进行结构损伤评估。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。

The broader impact of this Small Business Innovation Research (SBIR) Phase I project will be in the railroad, civil infrastructure, and engineering services industries, by providing engineering firms and infrastructure owners the means to enhance public safety while significantly reducing the costs of bridge infrastructure monitoring and revenue losses due to infrastructure downtime due to sudden events. Thousands of sudden events, such as vehicle impacts and overweight vehicle crossings, occur annually on the over 700,000 bridges in the U.S. Many go unnoticed or unreported, despite their potential to induce structural failures or hidden damage that significantly reduces the structure's service life. This project will provide a cost-effective wireless solution to detect, quantify, and report sudden events on civil infrastructure in near real-time. The proposed solution will replace three existing types of monitoring systems with one compact, easy-to-deploy device at a fraction of the cost of even a single legacy system. The rapid condition assessment capability will further reduce traffic disruption, thereby lowering daily economic losses that can range in the millions of dollars and offering the potential to make the nation's transportation infrastructure safer.The proposed project seeks to develop a smart IoT monitoring system for rapid condition assessment of civil infrastructure under sudden events. Wired systems are prohibitively expensive for most structures, particularly bridges in remote locations, and existing wireless solutions following a duty-cycle approach to reduce power draw are incapable of always-on monitoring needed for sudden event detection. The objective of the research is to develop a low-cost IoT system to maintain always-on monitoring, so as not to miss an event, under a minimal power budget, without sacrificing data fidelity, and with a very low false positive rate. To this end, an asynchronously-triggered, synchronized data acquisition method will be developed, using high-fidelity wireless sensors that are tightly coupled with a programmable event-based switch capable of always-on operation. This method would enable the system to maintain ultralow-power operation indefinitely, and upon event detection, to rapidly transition to high-fidelity measurement. Uniquely, the pre- and post-event data are processed and stitched together across multiple sensors without the need for a priori synchronization. Experiments will be conducted to demonstrate the system?s capabilities to capture the onset of sudden events and present structural damage assessment in near real-time.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.