Current Issue : April - June Volume : 2019 Issue Number : 2 Articles : 5 Articles
The wing, one of the most important parts of aircraft, always requires sophisticated\ndesign to increase lift, reduce drag and weight. For modern fixed-wing\nUAV, extending cruising time is always a requirement for the overall design.\nDesigning a most light wing that can match the requirements of work conditions\nis desired. In this work, according to the work conditions, we compare\nseveral types of wing and chose beam-type wing. Then we made the detailed\ndesign and optimization to reduce the weight of wing. At last, we draw the 3D\nmodel for potential realistic production....
In order to control the position and attitude of unmanned aerial vehicle (UAV) better in different environments, this study\nproposed a hybrid control system with backstepping and PID method for eight-rotor UAV in different flight conditions and\ndesigned a switching method based on altitude and attitude angle of UAV. The switched process of hybrid controller while\nUAV taking off, landing, and disturbance under the gust is verified in MATLAB/Simulink. A set of appropriate controllers\nalways matches to the flight of UAV in different circumstances, which can speed up the system response and reduce the\nsteady-state error to improve stability. The simulation results show that the hybrid control system can suppress the drift\nefficiently under gusts, enhance the dynamic performance and stability of the system, and meet the position and attitude of\nflight control requirements....
The collaborative combat of manned/unmanned aerial vehicles (MAVs/UAVs) is a popular topic in combat application research. It\nmaximizes the autonomous combat capability of UAVs and the control capability of MAVs. Furthermore, it improves the\ncomprehensive combat effectiveness. The quantitative description of intercommunication in different aircrafts along with the\nevaluation of the collaborative combat capability is an emphasis in military research. This paper analyzes the collaborative\ncombat process. Node and edge models are established in the MAV/UAV collaborative network. The intercommunication and\ncombat behaviors among combat entities are analyzed. Based on the information entropy, the effect of capability uncertainties\non the collaborative combat is described quantitatively. An evaluation method of the MAV/UAV collaborative combat\ncapability is proposed. Finally, an example is given to demonstrate the proposed model and evaluation method that prove its\nfeasibility and effectiveness....
Aerodynamic interactions between rotors are important factors affecting the performance\nof in-plane multirotor Unmanned Air Vehicles (UAVs) or drones, which are the majority of small\nsize UAVs (or mini-drones). Optimal design requires knowledge of the flow features. The low\nReynolds number of many UAV rotors raises the question of how these features differ from those\nexpected by traditional analytical methods for rotorcraft. Aerodynamics of a set of side-by-side\nrotors in hover over a range of rotor separation and Reynolds number is studied using high-speed\nStereo Particle Image Velocimetry (SPIV) and performance measurements. The instantaneous and\ntime-averaged SPIV data presented here indicate an increase in inter-rotor wake interactions with\ndecrease in rotor spacing and Reynolds number. A dip in rotor efficiency at small rotor spacing at\nlow Reynolds number is observed through thrust and torque measurements. The basic components\nof in-plane multirotor wake and velocity profiles are identified and discussed to help generalize the\nfindings to a wide range of drones. However, the data provide confidence in traditional analysis\ntools, with small modifications....
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