MBDyn - Free MultiBody Dynamics Simulation Software MBDyn features the integrated multidisciplinary analysis of multi-body, multi-physics systems, including nonlinear mechanics of rigid and flexible constrained bodies, smart materials, electric networks, active control, hydraulic networks, and essential fixed-wing and rotorcraft aerodynamics. It allows you to simulate the behavior of heterogeneous mechanical, aero-servo-elastic systems based on first principles equations. It is being actively developed and used in the aerospace and automotive fields for dynamics analysis and simulation of complex systems. The extension of available analysis domains to new models, and new analysis domains, is planned and problem-driven.