Diagram (IMAGE) American Institute of Physics Caption This is a diagram of the slider-crank mechanism that generates energy during the knee's motion. Credit Gao et al. Usage Restrictions Journalists may use this image only with appropriate credit. 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.