Inspector Gadget

Spider-Man's robotic twin takes the hassle and expense out of building inspections

The City Climber is a 2.2-pound wheeled robot that can speed across ceilings, scale brick walls, even spy into open windows. But inventor Jizhong Xiao of the City College of New York says that its immediate job will be much more practical: to scour urban facades for cracks, loose bricks and other trouble spots.

Inspections of high-rise buildings require scaffolding machinery, technicians and engineers, to the tune of roughly $5,000 a day for a 10-story building. Xiao's robotic stand-in, which will perform a test inspection this fall in New York City, can do the job in about half the time and for less than half the cost.

The battery-powered City Climber combines two suction techniques to hug a wall tightly. One works like a vacuum and another like a tornado, spinning air to create a low-pressure zone in the center of the vortex. The resulting sticking power enables the robot to lug inspection gear like cameras and sensors. A safety tether keeps it from plummeting to the sidewalk should it lose its grip. Future models, Xiao says, will work in teams, using sensors to track one another'
s position as they crawl.