Results 1 to 10 of about 7,948 (233)

Lifting and Transport of Martian Dust by the Ingenuity Helicopter Rotor Downwash as Observed by High-Speed Imaging From the Perseverance Rover. [PDF]

J Geophys Res Planets, 2022
Lemmon MT, Lorenz RD, Rabinovitch J, Newman CE, Williams NR, Sullivan R, Golombek MP, Bell JF, Maki JN, Vicente-Retortillo A.   +9 more
europepmc   +1 more source

Hysteresis Compensation for a Piezoelectric Actuator of Active Helicopter Rotor Using Compound Control. [PDF]

Micromachines (Basel), 2021
Zhou J, Dong L, Yang W.
europepmc   +1 more source

Design of Unmanned Helicopter Distributed Electric Tail Rotor Controller Based on Improved Active Disturbance Rejection Control

IEEE Access
In response to the critical implications of single tail rotor failures in unmanned helicopters, this study proposes a distributed electric tail rotor yaw channel controller that employs Active Disturbance Rejection Control (ADRC) techniques.
Qing-Xin Zhang, Yun-Feng Ji, Feng Wang, Lei Pei, Zheng-Ming Cha   +4 more
doaj   +1 more source

CALCULATED RESEARCH OF INFLUENCE OF HELICOPTER MAIN ROTORS GEOMETRY ON THE EFFICIENCY IN HOVER MODE BASED ON THE NONLINEAR VORTEX MODEL

Научный вестник МГТУ ГА, 2018
The efficiency of the helicopter main rotor in the hover mode is very important, because this mode essentially determines the performance characteristics of the helicopter.
Y. M. Ignatkin, P. V. Makeev, A. I. Shomov   +2 more
doaj   +1 more source

A Case of Penetrating Head Wound Due to Helicopter Rotor Blade Injury in a 34-Year-Old Naval Helicopter Pilot Who Returned to Active Service 5 Years Later. [PDF]

Am J Case Rep, 2021
Hsieh CC, Chan PY, Liou LR, Chen YK, Tsao MJ, Chen LF, Lin KH.   +6 more
europepmc   +1 more source

Study on dynamic characteristics of the helicopter main transmission system

Jixie chuandong
ObjectiveTo identify the main excitation frequencies that cause the vibration of the helicopter main transmission system and reveal the influence of system speed, rotor torque, and rotor lift on the dynamic characteristics of the helicopter main ...
XU Huachao, XU Zhiliang, WANG Yong, FAN Mengyang, YANG Longze, LIAO Hongjun   +5 more
doaj  

INTERFERENCE BETWEEN HELICOPTER AND ITS SURROUNDINGS, EXPERIMENTAL AND NUMERICAL ANALYSIS

TASK Quarterly, 2009
The paper describes the phenomenon of the occurrence of aerodynamic interference between a helicopter and an object in its near vicinity. Such situations occur during rescue missions as well as during police and military operations when the helicopter ...
TOMASZ ŁUSIAK, ADAM DZIUBIŃSKI, KAZIMIERZ SZUMAŃSKI   +2 more
doaj  

Research of the crosswind effect on the single-rotor helicopter unintentional yaw rotation

Научный вестник МГТУ ГА
During the operation of single-rotor helicopters, aviation accidents quite frequently occur in the form of an unintentional turn or even a yaw rotation, causing, as a rule, a ground collision.
V. V. Efimov, V. A. Ivchin, K. O. Chernigin   +2 more
doaj   +1 more source

Active twist of model rotor blades with D-spar design [PDF]

Transport, 2007
The design methodology based on the planning of experiments and response surface technique has been developed for an optimum placement of Macro Fiber Composite (MFC) actuators in the helicopter rotor blades.
A. Kovalovs, E. Barkanov, S. Gluhihs
doaj  

Adaptive Vibration Control for Helicopter with Active Rotor Using Double-Acting Piezoelectric Actuator

Aerospace
Active rotors with trailing-edge flaps (TEFs) are a promising method applied to the main-rotor blades of the helicopter for vibration suppression. For active rotors, both the TEF actuator and the corresponding deflection control law determine their ...
Xiancheng Gu, Weidong Yang, Linghua Dong, Jinlong Zhou   +3 more
doaj   +1 more source