Construction and Modeling of a Two-Degree-of-Freedom Helicopter

This paper presents the stages in the construction of a two-degree-of-freedom (2DOF) helicopter from scratch, and the process followed to obtain its dynamical model. The modeling is carried out in three phases. In the first phase, the model of the motor and the propulsive forces are obtained using Newton´s second law of motion. In the second phase, the Lagrange´s equations of movement are applied to describe the complete dynamics of the system. In the third phase, a fitting process is developed in order to adjust the model to the behavior of the built prototype. Finally, in order to validate the accuracy of the model, the responses from the obtained model and from the real 2DOF helicopter are compared.