Boring can be frustrating, and boring (pun intended) when you encounter rocks that can destroy your drilling equipment.
A robot called Swifty, created by a San Francisco-based start-up Petra, can drill through the hardest rocks on the planet, which would normally destroy drilling equipment, using super-heated gas. Petra’s semi-autonomous tunneling robot offers fast and cheap solutions for infrastructure projects.
“Every method that's commercially available is a high-contact method that grinds up the Earth it contacts in order to remove it,” Kim Abrams, the founder of Petra, says. “This is a completely new way to tunnel.”
How it works
The company previously used plasma to melt the rocks to drill through but the extreme heat above 10,000°F (Over 5,500°C) turned the rocks into lava. This made Petra turn to colder options.
Abrams says the drilling robot can bore a 24-inch tunnel through 20 feet of Sioux Quartzite, "the hardest rock on earth ... harder than bluestone granite ... the type of rock that would normally have to be dynamited," as she described in a CNBC interview.
The robot has sensors attached to small rods which touch the rock, but the excavation is carried out by applying heat and gas.
The semi-autonomous robotic system can create 18-60 inch (46-152 cm) diameter tunnels through the hardest geologies with a non-contact thermal drill that melts any type of rock by heating a mixture of gas to apply heat above 1,800° Fahrenheit (982° Celcius) that breaks rocks into small pieces.
“…we averaged an astounding one-inch-per-minute in a geology usually excavated by dynamite,” said Petra’s CTO and a Tesla co-founder Ian Wright, in a press release. “No tunneling method has been able to tunnel through this kind of hard rock until now. Petra’s achievement is due to Swifty’s thermal drilling method which efficiently bores through rock without touching it.”
The robot’s progress through Sioux Quartzite is at a rate of an inch per minute using machine vision and can reverse out of the tunnel it drilled. This technology enables Petra to reduce costs of tunneling through bedrock to bury electricity and other lines underground by 50 to 80 percent, according to company estimates.
Petra’s future plans include testing its method outside of the laboratory on projects involving various rock types such as granite, dolomite, limestone, and basalt to try to prove that its method can work in places like California, Colorado, and the Appalachian Mountains.