Abstract: The book is devoted to building and analysis of mathematical models of complex systems including mechanical, electrical and electronic components. A general method of computer-aided model construction for mechatronic systems is developed. The method is applied to concrete mechatronic system consisting of the support, four springs and two unbalanced rotors, driven by DC-motors. A solution to the identification problem is presented. The complete computer model of the system in MATLAB language is described. Simulation results confirm that behavior of the model is adequate to experimental data.