Vans With Lasers Are Telling Engineers Which Roads to Fix First

The white Ford van rumbled down Devonshire Avenue, past the green-trunked palo verde trees and graveled lawns of central Phoenix. Lasers up front mapped the road’s roughness, and high-definition cameras on spider-like arms in back recorded continuous images of cracked asphalt.

With 65 percent of U.S. roads rated in less than good condition, cities and states no longer leave funding decisions to intuition and influence. Instead, they use data vacuumed up by arachnid-armed “spider vans” with bulbous cameras and global-positioning equipment protruding from roofs. Six computers inside Phoenix’s four-ton vehicle stored data for engineers to download.