Andy Ruina’s 22-pound, four-legged bi-ped robot named Ranger | The Kid Should See This https://thekidshouldseethis.com/post/21323035096
After a friend tweeted about a research page full of passive motion robotics videos by Andy Ruina, Professor of Theoretical and Applied Mechanics at
Wind up bots in the streets of Buenos Aires Rion NakayaFebruary