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This paper presents a comprehensive modeling approach for tail-sitter hybrid UAVs featured by vertical take-off and landing (VTOL) and cruise flight capabilities. The modeling approach includes all essential components, such as full angle of attack envelope wing and fuselage aerodynamics, sideslip wind effect and actuator dynamics. A unified formulation comprising all model components is derived to...
Aggressive maneuvers for micro unmanned aerial vehicle (MAV) require short settling time for attitude reference tracking and small overshoot for stabilization, which leads to the implementation of composite nonlinear feedback (CNF) control method. In this paper, an MAV platform is customized with all of the sub-systems designed to be small in size factor and simplified with their functionality. A...
Majority of today's fixed-pitch, electric-power quadrotors have short flight endurance (< 1 hour) which greatly limits their applications. This paper presents a design methodology for the construction of a long-endurance quadrotor using variable-pitch rotors and a gasoline-engine. The methodology consists of three aspects. Firstly, the rotor blades and gasoline engine are selected as a pair, so...
The principle of a dual mechanical port (DMP) machines is proposed in 2002 [1], and since then, many different topologies of DMP machines have been proposed [2]. The structure of the DMP machine which has been proposed in [3] is compromised by inner motor and outer motor, the inner motor is compromised by inner rotor and outer rotor, and the outer motor is compromised by outer rotor and the stator,...
Mechanical gearbox, which plays significant roles in vehicular transmission system, inherently suffers from the drawbacks of wear-and-tear and regular maintenance [1]. Magnetic gears are considered as the preferred gearing device for vehicular transmission system because they have the merits of silent operation, maintenance free and physical isolation. However, the gear ratio of magnetic gear is fixed...
In this work, we provide a nonlinear mathematical model identification methodology of an autonomous micro quadrotor, and the design of its orientation and position controllers. In the model identification, we specifically focus on the brushed D.C. motor dynamics, which further breaks down into three different segments: voltage generation, motor dynamics, and force/torque generation. Test bench experiments...
The recent development of small yet sophisticated sensors has led to the development of smaller unmanned aerial vehicles, especially in the form of quadrotor. When it is limited by the availability of the reverse propellers, the conventional quadrotor will no longer be realizable, and thus introducing the 4-standard-propeller (4SP) quadrotor design. This paper presents a comprehensive nonlinear modeling...
This paper presents the work that has been done to derive an accurate nonlinear model for a miniature fixed-pitch coaxial helicopter. Starting from the Newton-Euler rigid body dynamic equations, forces and torques generated at various parts of the UAV have been identified and formulated. The physical meanings behind the model are clearly explained, and the methods of identifying all the important...
This paper presents a thorough structural analysis to a helicopter dynamic model using the special coordinate basis decomposition technique, which is capable of capturing the structural properties of a given system, such as the finite and infinite zero structures as well as the invertibility structures in different actuator/sensor configurations. They are important to guide a successful control design...
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