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Technical Paper

Control, Propulsion and Energy Assessment of a Spherical UAS for Low Speed Operations

2017-09-19
2017-01-2065
This paper presents a comparison between different hypotheses of propulsion of a spherical UAS. Different architectures have been analyzed assessing their specific aerodynamic, energetic, and flight mechanics features. ...An effective energy assessment and comparison against a commercial UAS has been produced. Even if the paper considers a preliminary simplified configuration, it demonstrates clearly to be competitive against traditional quadcopters in a predefined reference mission.
Technical Paper

Nonlinear Slender Beam-Wise Schemes for Structural Behavior of Flexible UAS Wings

2015-09-15
2015-01-2462
The innovative highly flexible wings made of extremely light structures, yet still capable of carrying a considerable amount of non- structural weights, requires significant effort in structural simulations. The complexity involved in such design demands for simplified mathematical tools based on appropriate nonlinear structural schemes combined with reduced order models capable of predicting accurately their aero-structural behaviour. The model presented in this paper is based on a consistent nonlinear beam-wise scheme, capable of simulating the unconventional aeroelastic behaviour of flexible composite wings. The partial differential equations describing the wing dynamics are expanded up to the third order and can be used to explore the effect of static deflection imposed by external trim, the effect of gust loads and the one of nonlinear aerodynamic stall.
Journal Article

Optimization of an Unmanned Aerial System' Wing Using a Flexible Skin Morphing Wing

2013-09-17
2013-01-2095
In this paper, we describe a practically efficient methodology of improving the aerodynamic characteristics of an UAS's wing using a morphing approach. We have replaced a part of the original wings' upper and lower surfaces with a flexible, composite material skin whose shape can be modified, according to the variable airflow conditions, using internally placed actuators. ...We have used the optimization tool to decrease the overall drag coefficient of a military grade UAS' wing equipped with the flexible skin. We have obtained good quality solutions for only a fraction of the computational cost needed when performing viscous flow field calculations.
Technical Paper

Recommendation of Experimental Setup and use of Standardized Electrohydrodynamic Dimensionless Parameters for Optimization of a Dielectric Barrier Discharge Flow Control Device

2014-09-16
2014-01-2101
The high demand for traditional air traffic as well as increased use of unmanned aerial systems (UAS) has resulted in researchers examining alternative technologies which would result in safer, more reliable, and better performing aircraft. ...The paper listed a comprehensive set of standardized dimensionless numbers derived from the EHD conservation equations and recommended the use of these standardized parameters be used in experimental work investigating EHD systems.[1] The following paper will recommend which of the parameters require further examination for the DBD device, as well as propose experimental methods for achieving an optimized plasma actuator, with special emphasis on low altitude, low speed applications commonly encountered by the majority of fielded UAS.
Magazine

Aerospace & Defense Technology: February 2023

2023-02-09
Design and Analysis of a Small Unmanned Aerial System (UAS) Power Distribution System All electrically powered autonomous vehicles possess a system that distributes power to all the vital components of the vehicle.
Technical Paper

Numerical and Experimental Measures of the Unmanned Aerial System UAS-S4 of Hydra Technologies

2014-09-16
2014-01-2145
This article presents a structural analysis of the Unmanned Aerial System UAS-S4 ETHECATL. Mass, center of gravity position and mass moment of inertia are numerically determined and experimentally attested using the pendulum method. To determine the mass moment of inertia, a bifilar torsion-type pendulum is used for the Z-axis and a simple pendulum for the X and Y axes [14]. A nonlinear dynamic model is developed for the rotational motion about the center of gravity (Gs) of the tested system, including the effects of large-angle oscillations, aerodynamic drag, viscous damping and additional mass effects. MATLAB genetic algorithms are then used to obtain the values of mass moment of inertia that would validate the experimental data with the numerical results. The experiment used data gathered by three sensors: an accelerometer, a gyroscope and a magnetometer. Therefore, a method is used to calibrate these three sensors.
Magazine

Momentum: February 2014

2014-02-01
Evaluation of heavy-vehicle aerodynamic drag In an attempt to achieve a balance between Reynolds number, model scale, and tunnel blockage issues, a 1:3 scale heavy-vehicle testing program has been initiated at the Monash University 1.4-MW wind tunnel. Validating performance suspension parts advances A forum at the 2013 SEMA Show discussed three approaches to ensure performance parts compliance with Federal Motor Vehicle Safety Standard 126. Panelists also explained how simulation data, and kinematics and compliance measurements, can improve performance parts design. Active safety starts in the pilot's seat Dassault Aviation's next-generation integrated digital avionics systems contribute to enhanced air safety in civil applications. Chevrolet ups the performance ante with MY2015 Corvette Z06 Stiffer-bodied sports car gains wind-aided performance with supercharging and downforce for faster lap times.
Magazine

Momentum, the Magazine for Student Members of SAE International 2012-09-28

2012-09-28
Shed a few joules with better aerodynamics A team of engineering students from Laval University has managed to reduce the energy demand due to wind resistance of its Supermileage vehicle by 10% after carefully designing a new vehicle body with a 25% larger frontal area. Telemetry helps Formula SAE team close the loop on design Once a year, a team of students at Virginia Tech get to do something that ought to put a grin on any aspiring engineer's face: build a racecar. Unconventional steel wheel designs The drawings done by collegiate students for a steel wheel design competition had industry professionals thinking about future production possibilities.
Magazine

Momentum, the Magazine for Student Members of SAE International 2011-09-29

2011-09-29
I was promised flying cars Though flying cars seem unlikely to become reality anytime soon, driverless vehicle technology is improving more quickly than you might expect. Quantum leaps toward world solar car title Armed with a dramatically lighter and aerodynamically cleaner racecar, the University of Michigan team likes its chances down under in the 2011 World Solar Challenge. Designing an aerodynamic undertray for a Formula style racecar Using CFD analysis, a master's student discovers an effective design for the undertray of a Formula SAE racecar. Hypersonic possibilities When it comes to reviving high-speed air travel, it all comes down to propulsion, propulsion, propulsion.
Magazine

Aerospace & Defense Technology: May 2017

2017-05-04
Interoperability Standards Pave the Way for Modular Robotic Manipulators Solar Powering UAVs Deploying COTS Subsystems in UUVs Developing a Multi-Modal UGV Robot Control Interface Fast-Tracking Autonomous Vehicles with Simulation Gesture-Based Controls for Robots: Overview and Implications for Use by Soldiers Identifying the Flow Physics and Modeling Transient Forces on Two-Dimensional Wings Experimental Confirmation of an Aquatic Swimming Motion Theoretically of Very Low Drag and High Efficiency The Scaling of Loss Pathways and Heat Transfer in Small Scale Internal Combustion Engines A Guide for Developing Human-Robot Interaction Experiments in the Robotic Interactive Visualization and Experimentation Technology (RIVET) Simulation
Article

Lockheed Martin validates heatshield for the Mars 2020 rover mission

2019-05-07
Lockheed Martin Corporation successfully completed development and testing for the heatshield that will protect NASA Jet Propulsion Laboratory Mars 2020 rover during its descent to the Martian surface. After completing the flight hardware structure, Lockheed Martin tested the heatshield’s physical integrity by exposing it to ‘flight-like’ thermal conditions.
Article

Lockheed Martin announces latest hypersonic progress at Le Bourget

2019-06-17
Lockheed Martin successfully flight tested the AGM-183A Air-Launched Rapid Response Weapon (ARRW) on a U.S. Air Force Boeing B-52 Stratofortress. The captive carry flight – announced during the 2019 International Paris Air Show – marks Lockheed Martin’s most recent demonstration of hypersonic technology development.
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