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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.

Current US military small unmanned aircraft systems (UAS) rely on engines and propellers sourced from the hobby radio-controlled (RC) aircraft industry. ...Torque, thrust, power, brake specific fuel consumption, (BSFC) and propeller efficiency data for a UAS engine are presented.

The project is framed within the Italian Aerospace Research Program, under the “UAV” Chapter. This UAS is mainly aimed at developing and validating advanced modeling methodologies for flexible aircrafts, where structural natural frequencies may overlap with flight dynamics frequencies. ...The vehicle will be given both remote piloting functions, either fully direct or mediated by a stability and control augmentation system, and fully autonomous flight capabilities. This UAS will also be used to provide CIRA and the whole scientific community with a valuable testing platform to support validation of flight technologies and carry out flight testing.

Abstract An accurate Unmanned Aerial System (UAS) Flight Dynamics Model (FDM) allows us to design its efficient controller in early development phases and to increase safety while reducing costs.

In recent years, there has been an increase in the use of Unmanned Aerial Systems (UAS) in the civilian sector for various purposes. As these platforms are constrained in terms of payload and capacity, they are typically equipped with a minimal sensor suite and the use of redundant sensors is uncommon.

This paper introduces a finite element (FE) approach to determine tire deformation and its effect on open-wheeled racecar aerodynamics. In recent literature tire deformation was measured optically. Combined loads like accelerating at corner exit are difficult to reproduce in wind tunnels and requires several optical devices to measure the tire deformation. In contrast, an FE approach is capable of determining the tire deformation in combined load states accurately. The FE tire model was validated using computer tomography images, 3D scan measurements, contact patch measurements and stiffness measurements. The deformed shape of the FE model was used in a computational fluid dynamics (CFD) simulation. A sensitivity study was created to determine the effect of the tire deformation on aerodynamics for unloaded and loaded tires. In addition, the influence of these tire deformations was investigated in a CFD study using a full vehicle model.

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.

Powering Better Battlefield Drones Using Low-Frequency Broadband Sonar on UUVs Experimenting in Realistic Environments Gets NewTechnology to Warfighters Designing Rugged SWaP-Optimized MOSA Solutions for UUVs Does Your UAV Program Need a Transponder? Understanding the Requirements and Guidelines Developing New Anti-Drone Radar Technology Deceiving the Enemy: These Are the Drones You Are Looking For By developing UAVs for physical deception roles to shape an adversary's ability to visually observe and orient to situations, the US military can decrease risk to air and ground combatants during mission execution by causing adversaries to expend resources, delay their reactions, or react incorrectly to tactical situations.

JPL transferred the license to Apollo after the company was awarded a contract to produce three engineering model MaSMi-EM thrusters for JPL’s Ascendant Sub-kW Transcelestial Electric Propulsion System (ASTRAEUS). Apollo will deliver the three MaSMi-EM thrusters to JPL this summer.

A cowling, or engine cover, is a critical airframe component that reduces drag and directing airflow into the engine. For the E-8C JSTARS, an aircraft with four massive Pratt and Whitney JT3D-based TF33-102C turbofan engines, each set of engine cowling components can cost up to $80,000 per set. Even a slightly warped cowling renders the entire housing unsafe and unserviceable.