These tiny robot crabs are controlled with a laser. With a structurally supportive polyimide (PI) skeleton, these peekytoe-like robots can walk, bend, twist, turn and jump via laser remote-control. In one application, researchers demonstrate the robots' usefulness as wireless environmental sensors by outfitting them with light retroreflectors that triggered them into action when materials in their environment changed color due to variations in humidity or ultraviolet light. Learn more under Pi Day in our Celebrations page! #PiDay #πDay, #PiDay2026 #DoesThisStillCountForPiDay🤨