JUNDEE, Australia—Hundreds of feet underground here, scientists are experimenting with a technology that could transform how mining companies dig out rocks in dangerous, pitch-black caves: fully autonomous drones.

The drones would fly without any pilot assistance into areas too risky for human miners. Using a rotating laser similar to those on autonomous cars, they would create three-dimensional maps more detailed than what is available now, helping miners excavate more gold and other commodities that might otherwise be missed.

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