柯林斯工程师正在与明尼苏达州的明尼苏达州运输部合作，恢复了明尼阿波利斯的詹姆斯·希尔·斯通拱大桥。19世纪的砌体结构应进行维修，Collins一直在使用Bentley Systems的Microsoft Hololens耳机使用Microsoft Hololens头戴式耳机，以在设计阶段加快检查工作。UAS，AI和现实建模的主管Barritt Lovelace说：“ HoloLens为我们提供了这种规模感。”“查看计算机屏幕时，您可以放大，但感觉不像桥在现场。与霍洛伦斯有所不同。”

Bridge inspections have always been dangerous, time-consuming work, but for assessing the condition of a structure, nothing beats being there. The Bentley mixed-reality workflow aims to bridge the gap between staring at photos and being on site. The workflow takes high-resolution drone photographs of the bridge, and stitches them into a “reality mesh” 3D model comprised of tens or hundreds of millions of polygons. This mesh contains far more information than is found in regular 3D models, says Dan Vogen, vice president, road and rail asset management at Bentley Systems. “It has all the texture, all of the current conditions, conveyed through the reality mesh.”

The reality mesh can be viewed on a computer or tablet, but a cloud-connected HoloLens offers a different viewpoint. There, the bridge can be viewed at a zoomed-out tabletop view or at 1:1 scale, letting engineers get up close and see every inch of the structure in high resolution. The engineer then can add annotations, perform measurements, and highlight potential problem areas.

“To me, the most impactful thing of putting your inspection notes on a model compared to traditional notes is you no longer have to describe where the defect is,” says Lovelace. “It definitely speeds up the process, and allows us to give MN-DOT better data.” While a HoloLens inspection is not meant to replace in-person inspections, Lovelace says it has reduced the number of trips needed to inspect the bridge and allowed engineers in other cities to help with the design work of the repairs without having to travel to Minneapolis. “We don’t have the budget to send everybody we want out there all the time,” he says. “But if someone in Chicago wants to help on the design of the cofferdams, they can look in HoloLens at the model.”

The HoloLens bridge inspection workflow is currently part of Bentley’s AssetWise system, and the reality meshes are linked up to the digital twins maintained of existing structures. Vogen says this is a natural next step for the digital twin approach. “We were told our digital twins were a solution looking for a problem,” he says. “But here is a problem we can really solve.” He adds that bridge inspection is only the first application for this workflow, and Bentley is already exploring Hololens as an inspection tool for other difficult-to-access structures, including communication towers and electrical utility transmission towers.

State Bridge Inspector Sees Promise in Drones, HoloLens

本特利·霍洛伦斯（Bentley Hololens）的工作流程还引起了MNDOT的注意，MNDOT在过去几年中一直投资于无人机进行桥梁检查。“我们现在正处于现在拥有这些无人机的地步，我们将使用它们进行检查。因此，我们有数据，我们如何使其有用？”MNDOT State Bridge检查工程师Jennifer L. Wells说。“现在是本特利和微软，我们可以在MNDOT的不同实体上共享这些数据。”

Wells has spearheaded the effort to bring drones into MnDOT's bridge inspection regime, and has worked with Collins Engineers in recent months to refine Bentley's HoloLens workflows.MnDOT has policies in place governing drone flights for bridge inspections为了遵守FAA法规，威尔斯说，该工作流程的一个版本可能成为有一天在该州进行桥梁检查的标准做法。她说：“ ​​[无人机]是我们工具包中的另一个工具。”“从车道关闭方面，它可以节省大量的时间和金钱。”

And while MnDOT and other state DOTs may have the resources for inspections, Wells points out that many local municipalities have a much tougher time inspecting all of the bridges and crossings in their jurisdictions. "We've seen some scope creep when it's time to close a bridge, because local agencies are not getting the access they need ahead of time [to inspect the bridge]." Spending a few thousand dollars on a drone and getting FAA certified as a drone pilot is one way for smaller agencies to get through their inspection work load quicker, Wells says.

But new technologies like reality meshes built from drone captures are only a part of the broader bridge-inspection process, she cautions. "It gives us a baseline to show changes over time, and show different departments within MnDOT," says Wells. "It's more of a first-line discussion creator—a better way than showing a picture from my smartphone to my load-rating engineer and asking 'can you draw up a load rating based on this?'" Working in a reality-mesh-based 3D model can solve a lot of those communication problems upfront, she says.

随着柯林斯工程师在斯通拱桥上的工作，威尔斯补充说，下一个项目已经开始工作，建立了布拉特尼克桥的无人机捕获现实网格，这是一座近60岁的整个桥梁桥梁，连接了明尼苏达州的德卢斯（Duluth），威斯康星州威斯康星州威斯康星州说，她希望无人机捕获，而新的HoloLens工作流将有助于加快衰老过境的检查工作。