This robot walks in footprints older than the dinosaurs. About two hundred and ninety-four million years old.
The footprints came first. For over a century, quarry workers in Germany split them out of the sandstone. Five toes, with rounded tips. For a long time, nobody could say what made them.
Then the same quarry gave up a skeleton. Complete, every bone in place, down to the toes.
This is Orobates. About three feet long, and as light as a house cat. It is not a reptile. It is a close cousin of the ancestor that reptiles and mammals share.
Scientists laid its toe bones against the prints. Toe for toe, they matched. The tracks belonged to its kind.
But bones and prints cannot show you a walk. Did it creep low, like a salamander? Or stand up on its legs?
So they built it. A robot with its proportions and its balance, driven by twenty-eight motors. In a computer, they tested five hundred and twelve ways it could walk.
Each walk had to stay steady, save power, and land on the tracks. Most of them failed.
The walks that passed held the body high, off the ground. Closer to a caiman than a salamander.
Walking tall was supposed to come later, with the reptiles. It seems Orobates was already doing it. The footprints waited a century for their animal. Now it walks them again.
