Frog-like robot will help surgeons

Researchers at the University of Leeds are using the feet of tree frogs as a model for a tiny robot designed to crawl inside patients' bodies during keyhole surgery. The tiny device is one of a growing stable of bio-inspired robots being built in the University’s School of Mechanical Engineering and featured on the BBC’s The One Show last night. It is designed to move across the internal abdominal wall of a patient, allowing surgeons to see what they are doing on a real-time video feed. The tree frog’s feet provide a solution to the critical problem of getting the device to hold onto wet, slippery tissue when it is vertical or upside down. Although it is relatively easy to find ways of sticking to or gripping tissue, the patterns on the frog’s feet offer a way to hold and release a grip without harming the patient. Lead researcher Professor Anne Neville, Royal Academy of Engineering Chair in Emerging Technologies at the University of Leeds, said: “Tree frogs have hexagonal patterned channels on their feet that when in with a wet surface build capillary bridges, and hence an adhesion force. It is the same kind of idea as a beer glass sticking to a beer mat, but the patterns build a large number of adhesion points that allow our robot to move around on a very slippery surface when it is upside down.