Abstract of Thesis presented at COPPE/UFRJ as a partial fulfillment of the requirements for the degree of Master of Science (M.Sc.)

Modeling and Identification of a Small Scale Helicopter

Fernando Pereira dos Santos

September/2008

Advisor:

Ramon Romankevicius Costa

Department:

Eletrical Engineering

      This work addresses the modeling and parameter identification of a small scale helicopter to be used in the design of position and atitude control systems. A nonlinear model is obtained from rigid body Newton­Euler equations, extended with the aerodynamic forces and moments and their respective dynamics. The identification parametric model is obtained from linearization, applying Taylor series expansion. This model is specified by transfer functions whose order were defined by the linearization performed. Data acquisition, signal processing and analysis are used to obtain parametric identification data. An electronic embedded system was developed to acquire sonar altimeter, inertial measurement unit and the pilots radio controller data. It also commands the helicopters servomotors. An automatic switching to manual mode (for security reason) and a mechanism to synchronize the taut­wire position measurements with the on board measurements were implemented as well. The nonlinear model is used to simulate these acquire conditions. The acquired data were processed with off­line algorithms and validated for application on helicopters position and atitude control design.