Science Daily  March 3, 2022 For many creatures under a certain size—like trap-jaw ants, mantis shrimp, and fleas—jumping across a surface is more energy-efficient than crawling. Researchers at the University of Pittsburgh built a robot about the size of a cricket made of a polymeric artificial muscle and replicated such movements. The curved composite shape of the polymer muscle allows it to build energy when it is powered to move along moving surfaces like sand as easily as hard surfaces, and even to hop across water. High speed imaging reveals tip velocities of several 100 mm s−1 with powers approaching […]