NISKAYUNA — Jet engines, MRI machines, electrical turbines, light bulbs.
Giant robotic earthworms.
This last item seems a most unlikely addition to the list of gadgets and technology General Electric engineers have developed or improved in the last century, but working prototypes of the wormlike robot have been burrowing through soil with increasing speed at the GE Research facility in Niskayuna.
The researchers posted a video of the latest wormbot, an 8-footer, pulsing through a box of dirt in a lab there.
Their work has landed GE a $2.5 million grant from an agency of the U.S. Department of Defense that promotes development of emerging technology. The feds are interested because of its potential for military use but it also has potential for civilian applications such as inspection and repair of industrial piping or wireless communication equipment.
“What you’re seeing is one of the many iterations we’ve built,” said project leader Deepak Trivedi. “These are prototypes that we design for proof of concept.”
The video shows fairly clearly how the concept works:
The robot is a series of segments each of which can expand greatly in diameter or length through air pressure. The lead segment tapers to a point and the following segments expand and contract in a rhythmic pulsing motion; the lengthening segments push the nose forward through the soil and the thickening segments keep the robot from sliding backward instead of forward.
“The trick lies in clever synchronization of the segments,” Trivedi said.
The Halfmoon resident is a mechanical engineer who did his graduate work in soft robotics, which is what the prototype is — soft, pliable machinery along the lines of an octopus tentacle or elephant trunk. Or an earthworm.
It’s more like an animal muscle than the traditional metal- or composite-framed robot.
“Essentially these are built by elastometric materials with fiberlike reinforcements,” Trivedi said.
The specialties of the dozen-strong team developing the robot include hydraulics, sensors, navigation, artificial intelligence, computers and electronics.
There are no worm experts in the group — the existing body of knowledge on worm propulsion is large enough that the team didn’t have to do its own research.
Nor did they need to duplicate the slimy mucus exterior of a worm — the robot doesn’t need a lubricant to get through soil.
“We can in no way match everything a biological creature does,” Trivedi said. “Our ultimate holy grail is to make this fully autonomous. Right now it’s all operated by a human.”
Autonomy would allow the robot to decide what to do with an object in its path that its human operator can’t see.
“Being self-aware of its capabilities, the robot will choose to break through an obstacle or work its way around it,” he said.
The current prototype can use air (pneumatic) or liquid (hydraulic) activation of the artificial muscles at up to 100 pounds per square inch. The team is using pneumatics now for ease of cleanup but the goal is a fully hydraulic worm that could operate at 500 PSI. With that much pressure, the robot will be more like a tree root than an earthworm, forcing its way through obstacles.
It’s not as hard as it might seem to fabricate all these things — many already exist on a shelf or in conceptual form somewhere within the GE Research inventory.
“A lot of these things, we just try to find whatever we have” on hand, Trivedi said. “We’ve made a lot of progress and what we’ve demonstrated so far is very encouraging.”
The concepts involve knowledge gained through GE’s development of healthcare and oil/gas extraction equipment that maps out things otherwise out of sight.
The current prototype is 8 feet long and 2 inches thick but expands to 10 feet long and 4 inches at the peak of its pulsing cycle.
This puts it within the specifications of the Defense Advanced Research Projects Agency’s Underminer program. Colorado School of Mines and Sandia National Laboratories also are involved in the project.
The performance targets call for the robot to be able to bore a tunnel 10 centimeters in diameter, which GE’s prototype can do, and proceed at 10 centimeters per second, which Trivedi and the team are holding it back from at this point. The video of the robot rapidly worming its way through soil in the lab is sped up 400 percent to better show the mechanics.
DARPA wants to demonstrate tunneling capacity for battlefield use but says the technology would have civilian applications as well including high-speed drilling and obstacle avoidance.