Close up view of valve mechanism (IMAGE) University of California - San Diego Caption The robot relies on a series of valves that open and close in a specific sequence to walk. Credit University of California San Diego Usage Restrictions Please credit University of California San Diego License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.