Design And Research Of A Dual-Rotor Technology Demonstrator

Tilt Rotor Aircraft is an emerging type of aircraft and has great practical significance in application. It is one of directions in helicopter aviation industry promoted by advanced nations. Technology of non coaxial dual-rotor helicopter is a foundation in researching tilt rotor aircraft, thus has sufficient research value. In this thesis, a research is boosted in order to realize a idea of dual-rotor aircraft, and the purpose is to ensure the aircraft has fundamental abilities to make its attitude under control. For accomplishing this task, an overall program is developed, subsequently a technology demonstrator of small dual-rotor unmanned aerial vehicle(UAV) is designed and fabricated. By means of mechanical, electronic and automation control systems, the demonstrator finally has corresponding capability in attitude control and its function is verified via specialized sets of jigs.Primarily, in this thesis, quadrotors and large helicopters are researched and an overall scheme is developed based on principle of quadrotor and mechanisms of large helicopter which warrant the dual-rotor’s attitude control by flight dynamics analysis. A single degree of freedom(DOF) swashplate is developed thus the demands of attitude control can be satisfied by simple mechanisms. The feasibility of the scheme is proved by theory of rotor aerodynamics.Then, details of components and mechanisms are designed and several key parts are improved. The demonstrator is built which can be used for experiments and technology demonstration.Subsequently, the Newton-Euler method is used in this thesis for mathematical modeling, dynamics equations are decoupled through small perturbation theory. The relevance between the dual-rotor helicopter’s equivalent control force and its flight attitude and state of motions are then exposed.After that, this thesis is dedicated on flight control system’s hardware/software design.By applying the methods of primitive rotation, quaternion and complementary filtering, data collected by inertial transducers and magnetometer are computated to obtain the craft’s flight attitude. Control scheme and software architecture are developed, a controller is designed by application of cascade PID.Finally, benefit from design of specialized experiment devices, a single DOF craft is assemble to test the controller by isolating pitch and yaw motions, experience of PIDcontroller tuning is mastered, performances of controller are discussed, attempts of control algorithm to enhance system’s robustness such as fuzzy adaptive control are tried. The feasibility of three DOF coupling control is demonstrated and eventually, the demonstrator is tested. With the result, it can be confirmed that the design plan of dual-rotor helicopter is available, the purpose of this thesis is accomplished and the phenomena observed in experiments point out directions for future research.