A material that mimics shark skin enables a swimming robot to move quickly through the water by improving hydrodynamics.

Li Wen, James Weaver and George Lauder at Harvard University in Cambridge, Massachusetts, used three-dimensional printing to embed thousands of rigid tooth-like scales on a flexible membrane (pictured), based on the skin structure of the shortfin mako shark (Isurus oxyrinchus). The authors compared the synthetic shark skin to a smooth control model in a robot swim test and found that the experimental skin moved 6.6% faster.

The skin eases swimming both by reducing drag and by generating vortices that boost thrust, the authors suggest.

Credit: James Weaver/Li Wen/George Lauder

J. Exp. Biol. 217, 1656–1666 (2014)