The Dutchroll project provides Open Source applications for Matlab and Simulink, with the emphasis on aerospace engineering. The main application is the Flight Dynamics and Control toolbox; other applications will be derived from that toolbox.
Symofros is a robotics modeling software originally created by the Canadian Space Agency. Symofros basic functions include modeling Kinematics, Non-linear dynamics, Linear dynamics, Dynamics for constrained systems, and Systems with flexible links.