Packs of dog-shaped robots could one day roam the moon — if they can find their footing on Earth first

"A dog is a man's best friend," the old saying goes. Can the same soon be said of robot dogs?

This summer, a group of scientists will Travel to Oregon's snow-capped Mt. Hood to train a dog-shaped robot named Spirit how to walk. The slopes of Mt. Hood are strewn with volcanic rocks and sprinkled with glaciers, a rugged environment that researchers think resembles the moon — which Spirit is being prepared to eventually explore.

"What we realized, pretty early on, is that a legged robot has the ability to interact with soil in ways that wheels cannot," Douglas Jerolmack, a professor of Earth and planetary Sciences at the University of Pennsylvania and the principal investigator of the project, said in a statement. "This interaction isn't just about mobility; it's about questioning and understanding the environment it moves through, in real time."

The $3 million Spirit, whose development is being funded by NASA, relies on its camera head and four metal legs, which "feel" the uneven terrain below, like a human testing the sturdiness of a frozen river with a few foot taps. Depending on the stability of the ground, Spirit should then adjust its speed and direction accordingly.

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Last summer, a test of how well Spirit sensed its environment on Mt. Hood revealed the robot could move across and over slushy snow as well as sprint on loose soil and boulders — though the robot occasionally stumbled and fell.

"We learn and improve from the observed failures," Feifei Qian, an assistant professor of electrical and computer engineering at the University of Southern California (USC) and the lead researcher of the project, said in a USC statement.