Researchers at CMU Robotics Lab have created gravity defying robots called Waalbots. The tiny hairs on a gecko’s feet, called setae, enable it to stick to surfaces. This is due to an intermolecular attraction between the setae and the surface, known as Van der Waals forces. A team at the NanoRobotics Lab, Carnegie Mellon University (CMU), has used a dry elastomer adhesive that mimics setae and enables a robot to climb walls and ceilings. However the CMU Waalbot has far greater sticking power because its fibers are twice as adhesive as the setae of geckoes.

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