Results 61 to 70 of about 51,014 (299)

The Evolution of Autonomous Systems for Planetary Cave Exploration: A Review

Journal of Field Robotics, EarlyView.
ABSTRACT The exploration of Subsurface Access Points (SAPs), such as lava tubes on the Moon and Mars, has gained significant interest due to their potential as stable environments shielded from surface radiation and temperature extremes. These sites are considered high‐value targets for detecting water and signs of ancient life, and assessing their ...
Sarah Swinton, Daniel Mitchell, Jamie Blanche, Euan McGookin, David Flynn   +4 more
wiley   +1 more source

Adaptive Feedforward Vibration Control of Helicopter Cabin Floor Driven by Piezoelectric Stack Actuators: Modeling, Simulation and Experiments

International Journal of Aerospace Engineering
Active control of structural response is the most practical and effective approach to mitigate helicopter vibration and enhance ride quality. In this paper, adaptive feedforward vibration control is constructed for the helicopter cabin floor driven by ...
Laishou Song, Yingquan Wang, Xiaoyu Shen
doaj   +1 more source

Overall Parameter Design and Transition Characteristics Analysis of Lift‑Tilt eVTOL

Nanjing Hangkong Hangtian Daxue Xuebao
The lift‑tilt configuration represents a prevalent architectural solution for electric vertical take‑off and landing （eVTOL） aircraft. Consequently， systematic investigations into its general parameter design principles， optimization methodologies， and ...
WANG Ziqi, XU Ming, SUN Donghong, ZHANG Wei, QIU Liangjun   +4 more
doaj   +1 more source

Safety during interhospital helicopter transfer of ventilated COVID-19 patients. No clinical relevant changes in vital signs including non-invasive cardiac output

Respiratory Research, 2022
Background During the COVID-19 pandemic in The Netherlands, critically ill ventilated COVID-19 patients were transferred not only between hospitals by ambulance but also by the Helicopter Emergency Medical Service (HEMS).
Cornelis Slagt, Eduard Johannes Spoelder, Marijn Cornelia Theresia Tacken, Maartje Frijlink, Sjoerd Servaas, Guus Leijte, Lucas Theodorus van Eijk, Geert Jan van Geffen   +7 more
doaj   +1 more source

Lacking data? No worries! How synthetic images can alleviate image scarcity in wildlife surveys: A case study with muskox (Ovibos moschatus)

Remote Sensing in Ecology and Conservation, EarlyView.
This study investigates the integration of synthetic imagery, created with diffusion‐based models, to supplement limited training data and improve muskox (Ovibos moschatus) detection in zero‐shot (ZS) and few‐shot (FS) settings. ZS models detected more than 80% of muskoxen in real images, confirming the potential of synthetic data as a substitute for ...
Simon Durand, Samuel Foucher, Alexandre Delplanque, Joëlle Taillon, Jérôme Théau   +4 more
wiley   +1 more source

Research on Whirl‑Flutter Characteristics of Distributed Propulsive Rotorcraft

Nanjing Hangkong Hangtian Daxue Xuebao
Aiming at the problem of whirl-flutter dynamics of distributed propulsion rotorcraft in high-speed forward flight state， this paper proposes a highly versatile， fast and efficient distributed multi-rotor/tilt-wing coupled aeroelastic dynamics analysis ...
CHENG Yi, YU Zhihao, WANG Siwen, ZHAO Jinrui   +3 more
doaj   +1 more source

Main rotor-tail rotor intraction and its implications for helicopter directional control

, 2008
Aerodynamic interference between the main and tail rotor can have a strong negative influence on the flight mechanics of a conventional helicopter. Significant unsteadiness in the tail rotor loading is encountered under certain flight conditions, but the
Fletcher, Timothy M., Brown, R.E., Fletcher, T.M.   +2 more
core   +1 more source

Monitoring feral pigs (Sus scrofa): Complementarity between autonomous sensing methods increases detection probability

Remote Sensing in Ecology and Conservation, EarlyView.
Invasive alien species are a major threat for biodiversity worldwide and effective monitoring is paramount to inform management. In this study we used a multi‐season occupancy model to assess probability of detection between camera traps and passive acoustic recorders for feral pigs (Sus scrofa) during 1 year of data collection.
Marina D. A. Scarpelli, Stewart Macdonald, Maryam Golchin, Simon Linke, Jens G. Froese   +4 more
wiley   +1 more source

Current Status of Research on Development and Application of Helicopter Landing Gear Technology

Nanjing Hangkong Hangtian Daxue Xuebao
As a key system for ensuring flight safety and mission adaptability， the technological innovation of helicopter landing gear has always revolved around overall design， advanced materials and manufacturing processes， core capability enhancement， and ...
FENG Shengquan, LI Qi, YANG Yun, CHEN Xiang   +3 more
doaj   +1 more source

Sensitivity of tail rotor noise to helicopter configuration in forward flight

, 2009
Understanding the mechanisms that lead to the production of noise by tail rotors across a broad range of flight conditions and helicopter configurations remains an active area of research.
Fletcher, Timothy M., Brown, R.E., Fletcher, T.M., Duraisamy, K., Duraisamy, Karthikeyan, Brown, Richard   +5 more
core