To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Movie S3. Propulsion of a two-stroke swimmer. The sequence of activation is controlled by the thickness of the shape memory muscle. The distance traveled is approximately 1.9l (where l is the length of the single actuator swimmer). Harnessing bistability for directional propulsion of soft, untethered robots Tian Chen, Osama R. Bilal, Kristina Shea, and Chiara Daraio PNAS. 2018. 115:5698-5702 DOI: 10.1073/pnas.1800386115 Download Original Video Browse All Videos »