With over 600 muscles in the human body, and the legs containing more than 100, modeling human motion is very complex, despite how much we take it for granted. Researchers at Stanford University’s School of Engineering have created OpenSim to model how we move. Medically, this can be a very powerful tool when attempting to treat diseases, such as cerebral palsy. The software can also aid preventative medicine, such as showing a person how their current gait could lead to joint damage. Visitors to The Leonardo, a science and technology museum in Salt Lake City, can experience this by walking over a pressure-sensitive floor. For younger museum patrons there is a display where they can control muscles in the legs to kick a soccer ball. The soccer demo is a simplified version of OpenSim, but still demonstrates the complexity of the muscles, as simply cranking up the strength does not work.
As the name suggests, OpenSim is open source and can be freely downloaded from opensim.stanford.edu.