Background

Digital Image Correlation (DIC) is widely used for remote and non-destructive structural health evaluation of infrastructure. Current DIC applications are limited to relatively small areas of structures and require the use of stationary stereo vision camera systems that are not easy to transfer and deploy in remote areas.

Objective

The enclosed work describes the development and validation of an Unmanned Aircraft System (UAS, commonly known as drone) with an onboard stereo-vision system capable of acquiring, storing and transmitting images for analysis to obtain full-field, three-dimensional displacement and strain measurements.

Methods

The UAS equipped with a StereoDIC system has been developed and tested in the lab. The drone system, named DroneDIC, autonomously hovers in front of a prestressed railroad tie under pressure and DIC data are collected. A stationary DIC system is used in parallel to collect data for the railroad tie. We compare the data to validate the readings from the DroneDIC system.

Results

We present the analysis of the results obtained by both systems. Our study shows that the results we obtain from the DroneDIC system are similar to the ones gathered from the stationary DIC system.

Conclusions

This work serves as a proof of concept for the successful integration of DIC and drone technologies into the DroneDIC system. DroneDIC combines the high accuracy inspection capabilities of traditional stationary DIC systems with the mobility offered by drone platforms. This is a major step towards autonomous DIC inspection in portions of a structure where access is difficult via conventional methods.

中文翻译：

---

基于无人机的StereoDIC：系统开发，实验验证和基础架构应用

背景

数字图像关联（DIC）被广泛用于基础设施的远程和非破坏性结构健康评估。当前的DIC应用仅限于相对较小的结构区域，并且需要使用不易在偏远地区转移和部署的固定式立体视觉摄像系统。

客观的

随附的工作描述了带有机载立体视觉系统的无人机系统（UAS，通常称为无人机）的开发和验证，该系统能够获取，存储和传输图像以进行分析以获得全场，三维位移和应变测量。

方法

配备了StereoDIC系统的UAS已在实验室中进行了开发和测试。名为DroneDIC的无人机系统在压力下自动悬停在预应力铁路枕木前面，并收集DIC数据。并行使用固定式DIC系统来收集铁路枕木的数据。我们比较数据以验证DroneDIC系统的读数。

结果

我们介绍了两个系统获得的结果的分析。我们的研究表明，我们从DroneDIC系统获得的结果与从固定DIC系统获得的结果相似。

结论

这项工作是将DIC和无人机技术成功集成到DroneDIC系统中的概念证明。DroneDIC将传统固定式DIC系统的高精度检查功能与无人机平台提供的移动性相结合。这是朝着通过常规方法难以访问的结构部分中的自主DIC检查迈出的重要一步。