Technology

Petra's remarkable thermal bore cuts through undrillable rock

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A combination of heat and high pressure allow this semi-autonomous boring robot to tunnel through undrillable rock
Petra
Petra's "Swifty" robot heats and pulverizes the hardest rock on Earth, without touching it
Petra
A combination of heat and high pressure allow this semi-autonomous boring robot to tunnel through undrillable rock
Petra
The Petra team bores through Sioux Quartzite, "the hardest rock on Earth" to demonstrate the tech
Petra
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San Francisco startup Petra says its new contactless thermal drilling robot can make steady progress through the hardest rock on Earth – stuff that would normally destroy drilling equipment – so quickly and cheaply that it could make a lot of underground infrastructure projects economically feasible.

The semi-autonomous "Swifty" robotic system can create 18-60 inch (46-152 cm) diameter tunnels through any geology, blasting the rock with an extremely hot, high-pressure spallation head such that it glows, chars and flings away.

Petra, founded by serial entrepreneur Kim Abrams, says it's demonstrated the robot's capabilities by boring a 24-inch tunnel through 20 feet of Sioux Quartzite – which Abrams describes in a CNBC interview as "the hardest rock on earth ... harder than bluestone granite ... the type of rock that would normally have to be dynamited." Swifty progressed at a rate of an inch a minute.

Petra's "Swifty" robot heats and pulverizes the hardest rock on Earth, without touching it
Petra

The company says this new robot uses a combination of remote control and machine vision to get its job done, and it's the first microtunneling robot that can reverse out of its own tunnel.

Costing "30-90 percent less than conventional trenchless methods," and opening up access to previously undrillable areas, Petra says its new tech will make it much more economically viable for governments and utilities to run vital power and communications cables underground, where they're safe from vandalism, wildfires, high winds and other threats.

Source: Petra

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27 comments
Robt
Plus it seems that there would be reduced shockwaves compared to dynamite; a big bonus for drilling in already congested underground city spaces
Can they be doubled, tripled up etc. to create a larger bore tunnel?
If so, this would be great for underground transit projects
SteveMc
Excellent news! I hope that Governments start looking towards moving many of the existing overland transport roads to underground and electrified networks so we can reclaim all the destroyed surfaces of the planet and eliminate pollution on a massive scale.
Brian Laich
20000+ of these machines, at their projected rate for 5 foot wide tunnels each for 1 year would give you underground railway under all the major interstates
Daveb
World’s most badass blow dryer
FB36
Maybe they got the idea from 2003 movie "The Core"? :-)
paul314
It reminds me a little of a project from the age of Peaceful Nuclear Power that one of my physics professors had been involved with, where they were drilling for geothermal energy by letting a small supercritical nuclear reactor core melt its way down.
Bodger
As this thing crawls/walks/rolls/whatever down the hole that it has bored where does the spalled waste go? How does it withstand the amazingly destructive heat that it generates while inside the bore hole? Are there environmental downsides to whatever heat source it is using? Just my inner engineer wondering...
Nobody
How is the waste collected and disposed of or will this become another source of pollution?
BlueOak
How does it do with tunneling thru dirt in between hard rock sections? Does it have to be pulled out and replaced with conventional drilling methods?
ljaques
Meh. A hot air gun combined with water jets to thermally fracture the rock. Pretty cool, but it's no molecular disgromulator.