Boring can be frustrating & boring (pun intended) when you come across rocks that can destroy your drilling equipment.
A robot called Swifty, created by Petra, a San Francisco-based startup, can drill through the hardest rocks on the planet, which would normally destroy drilling equipment, using superheated gas. Petra’s semi-autonomous robot offers fast & economical solutions for infrastructure projects.
“Each commercially available method is a high contact method that crushes the Earth it contact in-order to remove it,” says Kim Abrams, founder of Petra. “It’s a whole new way of digging tunnels.
How It Works
The company previously used plasma to melt rocks to be drilled, but extreme heat above 10,000°F turned the rocks into lava. This led Petra to choose cooler options.
Abrams states that the drilling robot can dig a 24-inch tunnel through 20 feet of Sioux quartzite, “the hardest rock on earth harder than bluestone granite … the kind of rock that should normally be dynamite, ”as she described in an interview with CNBC.
The robot has sensors attached to small rods that touch the rock, but the excavation is done by applying heat & gas.
The semi-autonomous robotic system can create 1860-inch diameter tunnels through hardest geologies with a non-contact thermal drill that melts any type of rock by heating a gas mixture to apply heat to the above 1800°F which breaks rocks into small pieces.
We had an astounding average of an inch per minute in geology typically excavated out by dynamite,” Ian Wright, CTO of Petra and co-founder of Tesla, said in a press release. “No tunneling method has been able to dig through this type of hard rock so far. Petra’s result is due to Swifty’s thermal drilling method which effectively dig through rock without touching it.
The robot’s progress through the Sioux quartzite is at rate of one inch per minute using machine vision & can reverse the tunnel it drilled. The technology allows Petra to reduce the cost of tunneling through bedrock to bury electricity & other underground lines by 50% to 80%, acc. to the company estimates.
Petra’s future plans include testing method outside of the lab on projects involving various types of rock such as granite, dolomite, limestone, & basalt to try and to prove its method can work in places like California, Colorado & the Appalachian Mountains.