20-sim is an advanced modeling and simulation package for Windows. With 20-sim you can simulate the behavior of dynamic systems, such as electrical, mechanical and hydraulic systems or any combination of these. 20-sim models may use iconic diagrams, bond graphs, block diagrams as well as differential equations. Used in mechatronics, control engineering, robotics, mechanical engineering, hydraulics etc. From the same lab as Tutsim. Follow the link and free download 20sim Viewer now.