Collins Engineers is working with the Minnesota Dept. of Transportation on the restoration of the James J. Hill Stone Arch Bridge in Minneapolis. The 19th-century masonry structure is due for repairs, and Collins has been using Microsoft HoloLens headsets with software from Bentley Systems to speed inspection work during the design phase. “The HoloLens gives us that sense of scale we only get in the field,” says Barritt Lovelace, director of UAS, AI and reality modeling for Collins Engineers. “When looking at a computer screen you can zoom in, but it doesn’t feel like the bridge is in the field. With HoloLens it is different.”
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.”