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To produce an ultralightweight machine for electric aircrafts, we propose a machine in which electrical energy is converted between the stator and the rotor via magnetic resonance coupling (MRC). This action causes electromagnetic resonance between the multiphase windings of the stator and the cage bars of the rotor. Electromagnetic resonance coupling technology allows electrical machines to convert...
In order to control the altitude of the quadrotor aircraft, an altitude control algorithm was proposed. Firstly, on the basis of analyzing the principle of quadrotor flight, a mathematical model of quadrotor was established. Secondly, feedforward control link and transition process link were arranged to PID feedback controller to enhance the control performance and altitude control precision of the...
This article shows development of a fixed wing Unmanned Aerial Vechicle (UAV) prototype with multi rotor control system. This model pretends increase flight time of multi rotor system using aerodynamic characteristics. The lift force generated by a wing reduce the required power of the motors to raise up the structure during horizontal forward flight. For airfoil selection and sizing of the wing,...
In Constant speed constant frequency (CSCF) AC power supply system, generator output constant frequency and constant voltage AC power by connecting engine with constant speed transmission device (CSD). However, CSCF has many disadvantages, such as complex structure, heavy weight, high cost and low energy conversion efficiency. By eliminating CSD in CSCF and taking output voltage and output frequency...
There has been a growing need for high specific power electrical machines for a wide range of applications. These include hybrid/electric traction applications, aerospace applications and Oil and Gas applications. A lot of work has been done to accomplish significantly higher specific power electrical machines especially for aerospace applications. Several machine topologies as well as thermal management...
This paper focuses on the transition flight control for a small tilt rotor unmanned aerial vehicle (UAV). Aiming at the longitudinal model of a tilt rotor UAV, a novel sliding mode control (SMC) method is proposed to guarantee that the states converge to the desired sliding surfaces in finite time. Moreover, extended state observers (ESOs) are provided to enhance the system's robustness to the uncertainties...
This paper proposes a finite-time control law for quadrotor aircraft to achieve position tracking control in a finite time. Firstly, the position dynamical equation and the attitude dynamical equation are introduced respectively. Secondly, based on the technique of finite-time control, a finite-time position controller is designed to ensure the desired trajectory can be tracked by the real position...
A novel tilt tri-rotor unmanned aerial vehicle (UAV) which combines the vertical flight capability of a helicopter and forward flight performance of an airplane is proposed. The two front rotors are able to tilt from the vertical to the horizontal position, however, the third rotor is fixed in the aft fuselage with a small angle. The nonlinear dynamic model of tilt tri-rotor UAV is given by the equations...
This paper presents a new structure of multicopter with its propellers installed in three different directions. The aim is to achieve complete independent control of position and attitude of the multicopter. This can allow us to control the position with its desired attitude controlled simultaneously. As such, this new multicopter can hover at any fixed point with its attitude changed freely. This...
The tilt tri-rotor UAV which combines the advantages of both rotary wing and fixed wing vehicle, offers the capability of hover, vertical take-off and landing and fast forward movement. Because of the complex structure and aerodynamics, the modeling and control of tilt tri-rotor UAV reamians a problem. In this paper, precise model of a tilt tri-rotor UAV is developed by combing system identification...
Many hybrid UAVs capable of vertical takeoff and landing (VTOL) and fixed-wing flight are being introduced for their maneuverability, efficiency and high cruise speed. The benefits of these systems can be exploited effectively using task planning frameworks tailored to their unique properties. To address this need, we present a motion planning strategy for these hybrid UAVs in cluttered urban settings...
With the goal of a skywriting unmanned aerial vehicle, a proof-of-concept design is presented. Drone swarms act as illuminated pixels for night-time aerial imagery. By contrast, this proof-of-concept employs a single quadcopter for day-time skywriting with smoke. This paper describes hardware and software selection and mounting configuration. A Snellen Chart approach is used to calculate appropriate...
The tilting trirotor presented in this paper is able to perform levelled flight at almost null attitude which is an important requirement for fixed wing tilt rotors in view of the lift control during transition from hovering to forward flight. The nonlinear dynamics, the large effect of wind due to the small scale, and the absence of aerodynamic data at low speed and Reynolds numbers, are crucial...
This paper presents a mixed-structure control system for a novel ducted fan aircraft in the presence of input constraint, system uncertainty and external disturbance. The control system includes mainly two parts: a robust nominal controller and a L1 adaptive augmentation. The robust nominal controller architecture consists of two loops. The inner-loop is designed as a static state feedback control...
This article addresses the trajectory-tracking problem for a miniature Quadrotor aircraft system using a super-twisting technique in real-time application. This strategy ensures the convergence in finite time to a desired programmed trajectory under bounded external perturbations such as wind gusts. The proposed solution consists of implementing a real-time strategy based on super-twisting control...
This paper presents the design and implementation of a cost-effective, lightweight, yet power efficient tail-sitter Vertical Take-off and Landing (VTOL) unmanned aerial vehicle (UAV). The UAV consists a pair of wings for efficient level flight and four rotors for attitude control. The aerodynamic and mechanical configurations of the UAV are designed and implemented from scratch to meet the required...
In this study, an attitude control method for multi-rotor aircraft with output constraints and various disturbances is presented. To prevent output constraints violation, a Barrier Lyapunov Function (BLF) is introduced and the controller is designed based on backstepping algorithm. To enhance the robustness of the system, a linear extended state observer (LESO) from linear active disturbance rejection...
This paper describes the development of a fault-tolerant, high specific output motor for use in aircraft electrical propulsion. The program includes demonstration of a full scale propulsion motor to a specification representative of an electric tail rotor drive on a medium twin-engine helicopter. The safety critical nature of the application demands a redundant system architecture comprising four...
This paper studies the control problem of tiltrotor transition mode, which requires the regulation of nacelle inclination from 0 to 90 degree based on a finite-time switching control technique. Because of the dynamic characteristic of tiltrotor conversion, a single system model can not meet the requirements for control precision. A switched system is used to characterize the multitudes of the system...
This paper contents theory interpretation of a propeller in yaw and experimental results of tests to determine the thrust, power and efficiency characteristics of a propeller Bambula 18×8 at various angles of yaw from 0° to 90°. The results of the wind tunnel tests can contribute to completing the aerodynamic calculation of fixed-pitch propeller aircraft especially for multicopters, whose rotors are...
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