These Terrifying Insectoid Skittering Robots Are For Cleaning Heating Ducts

This is what a modern-day chimney sweep looks like.

When was the last time you cleaned your central air or your heating ducts? Probably never, which means that they are festering tubes of matted filth, likely harboring all kinds of dangerous dirt. But who wants to clean ductwork? You’d only be encouraging spies and assassins to crawl through it, circumventing your low-tech, dirt-based security systems.


This robot, though, is like a modern-day chimney sweep, only it never needs feeding and doesn’t fall foul of child labor laws. It’s a tensegrity robot, a term coined by Buckminster Fuller to describe structures that combine stiff struts and taut cables to make a light, stiff structure.

Jeffrey Friesen’s DuCTT (Dual Compliant Tetrahedral Tensegrity) Robot comprises two interlocking pyramid-shaped aluminum frames, joined by cables. Using lightweight gears, these cables can be tensed and released. Thus, one section expands to push against the inside of the duct, then the other pushes forward. This section then grips, then the other releases and moves up into the forward section. The robot pulses through tubes like a caterpillar. In the videos you see it moving at just 40% of full speed.

DuCTT is “designed for navigation of complex duct systems,” says Friesen. “With the ultimate goal being autonomous inspection and cleaning of such systems.” That is, he’s making a robot chimney sweep. The project is part of his PhD research at the Flow Control and Coordinated Robotics Lab at the University of California San Diego, with contributions from Dynamic Tensegrity Robotics Lab and NASA.

Friesen’s ductbots might be great for keeping our heating and cooling systems clean, but they may also be terrifying for building residents. Image these things skittering through the ceiling as you try to sleep at night. “Is it a rat?” you’ll ask yourself. “Or is it something worse…?” If you ever find yourself living in a building serviced by these ductbots, do yourself one big favor: never watch the movie Aliens before bed.

About the author

Previously found writing at, Cult of Mac and Straight No filter.