Swedish automaker Volvo wants to make sure its self-driving trucks are able to operate in all environments, including inside a working mine 1,300 meters underground.

Volvo outfitted an FMX truck with sensors to monitor surroundings and recognize moving obstacles. The truck was able to maneuver through the mines without crashing, during the tests.

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“This is the world’s first fully self-driving truck to operate under such tough conditions. It is a true challenge to ensure that everything works meticulously more than 1300 metres underground,” said Volvo chief technology officer, Torbjörn Holmström.

The self-driving truck is also connected to a software platform that coordinates with other trucks in a fleet. Volvo says this platform can reduce fuel costs and improve production for industry fleets, like a truck that carries coal through a mine.

With Volvo truck tech, safety comes first

Holmström seems confident in Volvo’s self-driving system, at one point (video above) playing chicken with the truck.

“No matter what type of vehicle we develop, safety is always our primary concern and this also applies to self-driving vehicles,” said Holmström. “I was convinced the truck would stop but naturally I felt a knot in my stomach until the truck applied its brakes!”

Volvo has been very active in the self-driving industry in the past few months, it delivered 100 SUVs to Uber’s self-driving fleet in Pittsburgh and announced a partnership with Autoliv to build an autonomous system earlier this week.

Volvo is also actively testing its self-driving cars in China, Sweden, and the United Kingdom. The Swedish automaker wants to have a self-driving car on the road by 2020, but hasn’t given a similar timeframe for its self-driving truck.

It won’t be the only competitor in the self-driving truck market either, Daimler, the parent of Mercedes-Benz, is already testing autonomous trucks on public roads. Uber also recently purchased Otto, a self-driving truck startup, for $680 million.