1,587 research outputs found
Aeronautical Engineering: A special bibliography with indexes, supplement 69
This bibliography lists 305 reports, articles, and other documents introduced into the NASA scientific and technical information system in March 1976
Design of Flight Control Laws for a Novel Stratospheric Dual-Aircraft Platform
Dual-aircraft platform (DAP) is a novel concept that features two glider-like unmanned aerial systems (UAS) tethered via a thin adjustable cable allowing them to sail back-and-forth, without propulsion, using vertical wind shear. DAP offers the potential of a low-cost atmospheric satellite. This thesis presents the results of an initiative to demonstrate this novel flight concept through modeling, simulation, and flight testing at Embry-Riddle Aeronautical University (ERAU). A realistic simulation environment, described herein, was developed to support the development and testing of flight control systems. This environment includes nonlinear aerodynamic models for the aircraft, a multi-element cable dynamics model, propeller-motor thrust model, control surface actuator models, and permits time-varying wind profiles. This simulator offers both pilot-in-the-loop control and autonomous sailing flight control, and X-Plane interface to provide visualization cues. An intensive flight test program, described herein, was conducted to support the validation of the DAP concept. MAXA Pro 4m gliders were assembled, instrumented, and flight tested in an effort to physically demonstrate the sailing mode of flight. The flight test program described here focuses on the capability to sail with one aircraft (i.e., fly without propulsion) while towing (i.e., pulling) a moving truck as an intermediate step towards the more complex scenario of sailing with two connected aircraft. Two vital elements of the flight software are implemented and analyzed herein. The accuracy of wind estimation techniques is evaluated using flight testing. The robustness of an L1 adaptive controller is evaluated within the flight simulation environment by comparing its performance with a conventional controller
A survey of free software for the design, analysis, modelling, and simulation of an unmanned aerial vehicle
The objective of this paper is to analyze free software for the design, analysis, modelling, and simulation of an unmanned aerial vehicle (UAV). Free software is the best choice when the reduction of production costs is necessary; nevertheless, the quality of free software may vary. This paper probably does not include all of the free software, but tries to describe or mention at least the most interesting programs. The first part of this paper summarizes the essential knowledge about UAVs, including the fundamentals of flight mechanics and aerodynamics, and the structure of a UAV system. The second section generally explains the modelling and simulation of a UAV. In the main section, more than 50 free programs for the design, analysis, modelling, and simulation of a UAV are described. Although the selection of the free software has been focused on small subsonic UAVs, the software can also be used for other categories of aircraft in some cases; e.g. for MAVs and large gliders. The applications with an historical importance are also included. Finally, the results of the analysis are evaluated and discussed—a block diagram of the free software is presented, possible connections between the programs are outlined, and future improvements of the free software are suggested. © 2015, CIMNE, Barcelona, Spain.Internal Grant Agency of Tomas Bata University in Zlin [IGA/FAI/2015/001, IGA/FAI/2014/006
Aeronautical engineering, a continuing bibliography with indexes (supplement 197)
This bibliography lists 488 reports, articles and other documents introduced into the NASA scientific and technical information system in January 1986
Vertical Take-off and Landing Autonomous Aircraft Design
This project addresses the design, analysis, and and construction of an autonomous fixed-wing/rotorcraft hybrid aircraft capable of vertical take-off and landing. Autonomy is addressed to enable obstacle avoidance, visual detection of a landing target area, and accurate landing. The designed aircraft consists of a ducted main rotor and two smaller tilt-rotors, and is based on a similar design from the literature. This report provides detailed analyses of the aircraft\u27s aerodynamic and structural properties, dynamics and stability, propulsion, and power. The development of onboard autonomy using a 3D depth sensor is presented. Simulations of stabilizing controllers are presented. The construction of a prototype aircraft and its preliminary flight test results are reported
Aeronautical Engineering: A continuing bibliography with indexes, supplement 154
This bibliography lists 511 reports, articles and other documents introduced into the NASA scientific and technical information system in October 1982
Conceptual Design of a Combat Search and Rescue Surveillance Unmanned Aerial Aircraft
Unmanned aerial vehicles (UAV) are becoming more efficient and widely used. The military uses UAV’s because it greatly reduces civilian and combatant deaths and injuries. UAV’s also are used in search and rescue mission to find distress civilians. The team wanted to create an UAV for search and rescue missions and military applications. The aircraft needed to be compact, perform better than other UAV’s, and be low cost. The team did reach a successful aircraft that meet the design requirements. The aircraft was successfully sized around the electronics and allows utilization of additive manufacturing techniques. Project management techniques showed that with utilization of Work Breakdown Structure (WBS) chart, the team managed to specifically outline the scope of the project with very limited time
JSBSim library for flight dynamics modelling of a mini-UAV
This paper presents using of JSBSim library for flight dynamics modelling of a mini-UAV (Unmanned Aerial Vehicle). The first part of the paper is about general information of UAVs and about the fundamentals of airplane flight mechanics, forces, moments, and the main components of typical aircraft. The main section briefly describes a flight dynamics model and summarizes the information about JSBSim library. Then, a way of using the library for the modelling of a mini-UAV is shown. A basic script for lifting and stabilization of the UAV has been developed and described. Finally, the results of JSBSim test are discussed
Aeronautical Engineering: A special bibliography with indexes, supplement 74
This special bibliography lists 295 reports, articles, and other documents introduced into the NASA scientific and technical information system in August 1976
Integration, Testing, And Analysis Of Multispectral Imager On Small Unmanned Aerial System For Skin Detection
Small Unmanned Aerial Systems (SUAS) have been utilized by the military, geological researchers, and first responders, to provide information about the environment in real time. Hyperspectral Imagery (HSI) provides high resolution data in the spatial and spectral dimension; all objects, including skin have unique spectral signatures. However, little research has been done to integrate HSI into SUAS due to their cost and form factor. Multispectral Imagery (MSI) has proven capable of dismount detection with several distinct wavelengths. This research proposes a spectral imaging system that can detect dismounts on SUAS. Also, factors that pertain to accurate dismount detection with an SUAS are explored. Dismount skin detection from an aerial platform also has an inherent difficulty compared to ground-based platforms. Computer vision registration, stereo camera calibration, and geolocation from autopilot telemetry are utilized to design a dismount detection platform with the Systems Engineering methodology. An average 5.112% difference in ROC AUC values that compared a line scan spectral imager to the prototype area scan imager was recorded. Results indicated that an SUAS-based Spectral Imagers are capable tools in dismount detection protocols. Deficiencies associated with the test expedient prototype are discussed and recommendations for further improvements are provided
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