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79th Vertical Flight Society Annual Forum and Technology Display, FORUM 2023

作者： Gong, Anthony Tischler, Mark B. Shalev-Eggert, Ohad U.S. Army Combat Capabilities Development Command Aviation & Missile Center Moffett FieldCA United States Tischler Aeronautics SunnyvaleCA United States Rafael Advanced Defense Systems Ltd. Haifa Israel

ISBN: (纸本)9781713874799

Air launched effects refer to unmanned aerial vehicles deployed from another aircraft. These unmanned aircraft can perform intelligence gathering, surveillance, and reconnaissance in contested areas in place of or prior to the arrival of manned aircraft. A potential air launched effects candidate is the Unmanned Generic Coaxial Rotorcraft which has a cylindrical fuselage, folding rotor blades, and the capability to hover. A series of flight tests were conducted to collect test data for system identification. A bare-airframe flight dynamics model of the vehicle was identified using frequency domain methods and verified in the time domain with doublets. The existing vehicle's PX4 inner-loop flight control system was modeled in Simulink®, combined with the identified hover model, and validated against flight test data. The analysis model was then used to perform multi-objective optimization of the flight control system gains using a comprehensive set of specifications. The optimized control system is shown to have improved tracking and disturbance rejection performance over the baseline in simulation while meeting all desired specifications. Copyright © 2023 by the Vertical Flight Society. All rights reserved.

关键词： Flight control systems

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Post-Quantum Blockchain over Lattice

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Computers, Materials & Continua 2020年第5期63卷 845-859页

作者： Xiao Zhang Faguo Wu Wang Yao Wenhua Wang Zhiming Zheng School of Mathematics and Systems Science Beihang Universityand Key Laboratory of MathematicsInformatics and Behavioral SemanticsMinistry of EducationBeijing100191China Peng Cheng Laboratory Shenzhen518055China Beijing Advanced Innovation Center for Big Data and Brain Computing Beihang UniversityBeijing100191China Aviation Industry Development Research Center of China BeijingChina

Blockchain is an emerging decentralized architecture and distributed computing paradigm underlying Bitcoin and other cryptocurrencies,and has recently attracted intensive attention from governments,financial institutions,high-tech enterprises,and the capital *** cryptographic security relies on asymmetric cryptography,such as ECC,***,with the surprising development of quantum technology,asymmetric cryptography schemes mentioned above would become ***,lattice-based cryptography scheme was proposed to be secure against attacks in the quantum *** 2018,with the aid of Bonsai Trees technology,Yin et al.[Yin,Wen,Li et al.(2018)]proposed a lattice-based authentication method which can extend a lattice space to multiple lattice spaces accompanied by the corresponding *** their scheme has theoretical significance,it is unpractical in actual situation due to extremely large key size and signature *** this paper,aiming at tackling the critical issue of transaction size,we propose a post quantum blockchain over *** using SampleMat and signature without trapdoor,we can reduce the key size and signature size of our transaction authentication approach by a significant *** of using a whole set of vectors as a basis,we can use only one vector and rotate it enough times to form a *** on the hardness assumption of Short Integer Solution(SIS),we demonstrate that the proposed anti-quantum transaction authentication scheme over lattice provides existential unforgeability against adaptive chosen-message attacks in the random *** compared to the Yin et al.[Yin,Wen,Li et al.(2018)]scheme,our scheme has better performance in terms of energy consumption,signature size and signing key *** the underlying lattice problem is intractable even for quantum computers,our scheme would work well in the quantum age.

关键词： Blockchain post quantum lattice random oracle

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A Model for Spectrum Valuation

A Model for Spectrum Valuation

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Conference on Digital Avionics systems (DASC)

作者： Susan S.M. Hanson Leila Z. Ribeiro Carolyn A. Kahn Jack McQueston Connor Freeberg Stephen L. Giles Center of Advanced Aviation Systems Development (CAASD) The MITRE Corporation McLean VA

ISBN: (数字)9781728106496

ISBN: (纸本)9781728114972

The effective use of radio frequency (RF) spectrum has become more important as industry and government continue to increase their demand for bandwidth to enable new and improved wireless communications services. However practical supply of the resource is finite. Determining the market value of spectrum is a key step for stakeholders and decision makers to understand the impacts of RF spectrum investments, tradeoffs, and alternatives. 1 To meet this need, The MITRE Corporation (MITRE) developed a methodology and valuation model to assess the potential market value of various RF spectrum bands. The intent of the model is to allow non-industry experts to generate a range of possible valuations rather than a single point estimate and to inform decision makers about where the largest uncertainties exist that could influence the valuations. The spectrum valuation tool uses a novel approach to generate spectrum valuation. It integrates multiple regression models across the various factors that influence value, including transaction factors, network infrastructure factors, geographic factors, policy/economic factors, and consumer factors. This ensemble technique compensates for uncertainty between individual regression algorithms by integrating the results of a “group of experts” together to build a range of outcomes. This paper describes the methodology used to develop the spectrum valuation tool, the data included in the regression models, and the model's prediction capability with respect to the recently held Federal Communication Commission's 28 Gigahertz (GHz) auction.

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Predictive models of departure and arrival occupancy time and takeoff distance

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Journal of Air Transportation 2019年第2期27卷 81-95页

作者： Spencer, Thomas L. Trani, Antonio A. Center for Advanced Aviation System Development ATM Systems and Enterprise Engineering MITRE Corporation M/S N430 McLeanVA22102 United States Charles E. Via Jr. Department of Civil and Environmental Engineering Virginia Polytechnic Institute and State University Patton Hall 200 BlacksburgVA24061 United States

Values of departure and arrival runway occupancy time and takeoff distance are commonly used parameters for many airport and air transportation simulation models. However, these data are typically found either aggregated by weight or wake class or are otherwise unavailable. Furthermore, field collection of these data can be prohibitively time-consuming and expensive. To fill this data gap, predictive models of departure runway occupancy time, takeoff distance, and arrival runway occupancy time are presented. Through a comparison of multiple frameworks, it is found that the Bayesian modeling framework offers the strongest predictive performance. Using hierarchical Bayesian regression, the models developed cover 85 individual aircraft types and address the considerable variability present in the arrival and departure performances of different aircraft for clear weather conditions. © 2019 by The MITRE Corporation.

关键词： Aircraft

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Comparing interval management control laws for steady-state errors and string stability

Comparing interval management control laws for steady-state ...

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AIAA Guidance, Navigation, and Control Conference, 2018

作者： Weitz, Lesley A. Swieringay, Kurt A. The MITRE Corporation Center for Advanced Aviation System Development McLeanVA United States NASA Langley Research Center Crew Systems and Aviation Operations Branch HamptonVA United States

ISBN: (数字)9781624105265

ISBN: (纸本)9781624105265

Interval Management (IM) is a future airborne spacing concept that leverages avionics to provide speed guidance to an aircraft to achieve and maintain a specified spacing interval from another aircraft. The design of a speed control law to achieve the spacing goal is a key aspect in the research and development of the IM concept. In this paper, two control laws that are used in much of the contemporary IM research are analyzed and compared to characterize steady-state errors and string stability. Numerical results are used to illustrate how the choice of control laws gains impacts the size of steady-state errors and string performance and the potential trade-offs between those performance characteristics. © 2018 by the American Institute of Aeronautics and Astronautics, Inc.

关键词： Aircraft

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Predictive models of departure and arrival occupancy time and take-off distance 18th

Predictive models of departure and arrival occupancy time an...

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18th AIAA aviation Technology, Integration, and Operations Conference, 2018

作者： Spencer, Thomas L. Trani, Antonio A. The MITRE Corporation Center for Advanced Aviation System Development ATM Systems & Enterprise Engineering M/S N430 McLeanVA22102 United States Virginia Polytechnic Institute and State University Charles E. Via Jr. Department of Civil & Environmental Engineering Virginia Tech Patton Hall 200 BlacksburgVA24061 United States

ISBN: (数字)9781624105562

ISBN: (纸本)9781624105562

Values of departure and arrival runway occupancy time and take-off distance are commonly used parameters for many airport and air transportation simulation models. However, these data are typically found either aggregated by weight or wake class or are otherwise unavailable. Furthermore, field collection of these data can be prohibitively time-consuming and expensive. To fill this data gap, we present predictive models of departure runway occupancy time, take-off distance, and arrival runway occupancy time. Through comparison of multiple frameworks, we find that the Bayesian modeling framework offers the strongest predictive performance. Using hierarchical Bayesian regression, the models developed cover 85 individual aircraft types and address the considerable variability present in the arrival and departure performance of different aircraft. The additional benefit of the Bayesian model is its output of probability distributions, which many simulation models readily accept. © 2018, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Air transportation

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Design of an electric propulsion system for SCEPTOR 16th

Design of an electric propulsion system for SCEPTOR

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16th AIAA aviation Technology, Integration, and Operations Conference, 2016

作者： Dubois, Arthur van der Geest, Martin Bevirt, Joeben Clarke, Sean Christie, Robert J. Borer, Nicholas K. Joby Aviation Santa CruzCA95060 United States NASA Armstrong Flight Research Center EdwardsCA93523 United States NASA Glenn Research Center ClevelandOH44135 United States NASA Langley Research Center HamptonVA23681 United States 340 Woodpecker Ridge United States Advanced Systems Development Branch PO Box 273/MS4840D United States Thermal Systems Branch Brookpark Rd MS 86/12 21000 United States Aeronautics Systems Analysis Branch MS 442 United States

ISBN: (纸本)9781624104404

The rise of electric propulsion systems has pushed aircraft designers towards new and potentially transformative concepts. As part of this effort, NASA is leading the SCEPTOR program which aims at designing a fully electric distributed propulsion general aviation aircraft. This article highlights critical aspects of the design of SCEPTOR’s propulsion system conceived at Joby aviation in partnership with NASA, including motor electromagnetic design and optimization as well as cooling system integration. The motor is designed with a finite element based multi-objective optimization approach. This provides insight into important design tradeoffs such as mass versus efficiency, and enables a detailed quantitative comparison between different motor topologies. Secondly, a complete design and Computational Fluid Dynamics analysis of the air breathing cooling system is presented. The cooling system is fully integrated into the nacelle, contains little to no moving parts and only incurs a small drag penalty. Several concepts are considered and compared over a range of operating conditions. The study presents trade-offs between various parameters such as cooling efficiency, drag, mechanical simplicity and robustness. © 2016, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Drag

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Design and performance of the NASA SCEPTOR distributed electric propulsion flight demonstrator 16

Design and performance of the NASA SCEPTOR distributed elect...

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16th AIAA aviation Technology, Integration, and Operations Conference, 2016

作者： Borer, Nicholas K. Patterson, Michael D. Viken, Jeffrey K. Moore, Mark D. Clarke, Sean Redifer, Matthew E. Christie, Robert J. Stoll, Alex M. Dubois, Arthur Bevirt, JoeBen Gibson, Andrew R. Foster, Trevor J. Osterkamp, Philip G. NASA Langley Research Center HamptonVA23681 United States NASA Armstrong Flight Research Center EdwardsCA93523 United States NASA Glenn Research Center ClevelandOH44135 United States Joby Aviation Santa CruzCA95060 United States Empirical Systems Aerospace Inc. Pismo BeachCA93448 United States Aeronautics Systems Analysis Branch MS442 United States Advanced Systems Development Branch P.O. Box 273 MS4840D United States Thermal Systems Branch Brookpark Rd MS 86/12 21000 United States 340 Woodpecker Ridge United States P.O. Box 595 United States

ISBN: (数字)9781624104404

ISBN: (纸本)9781624104404

Distributed Electric Propulsion (DEP) technology uses multiple propulsors driven by electric motors distributed about the airframe to yield beneficial aerodynamic-propulsion interaction. The NASA SCEPTOR flight demonstration project will retrofit an existing internal combustion engine-powered light aircraft with two types of DEP: small "high-lift" propellers distributed along the leading edge of the wing which accelerate the flow over the wing at low speeds, and larger cruise propellers located at each wingtip for primary propulsive power. The updated high-lift system enables a 2.5x reduction in wing area as compared to the original aircraft, reducing drag at cruise and shifting the velocity for maximum lift-to-drag ratio to a higher speed, while maintaining low-speed performance. The wingtip-mounted cruise propellers interact with the wingtip vortex, enabling a further efficiency increase that can reduce propulsive power by 10%. A tradespace exploration approach is developed that enables rapid identification of salient trades, and subsequent creation of SCEPTOR demonstrator geometries. These candidates were scrutinized by subject matter experts to identify design preferences that were not modeled during configuration exploration. This exploration and design approach is used to create an aircraft that consumes an estimated 4.8x less energy at the selected cruise point when compared to the original aircraft. © 2016, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Propellers

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Block occupancy based surface surveillance

Block occupancy based surface surveillance

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Tyrrhenian International Workshop on Digital Communications - Enhanced Surveillance of Aircraft and Vehicles, TIWDC/ESAV

作者： Vilas Nene Ronald Chong Emily Stelzer Ronald Stevens Center for Advanced Aviation Systems Development The MITRE Corporation McLean Virginia USA

The proposed surface surveillance concept divides airport runways and taxiways into a number of operationally suitable, discrete, and contiguous sections called blocks. The system uses magnetometers or other suitable sensors positioned at each of the block boundaries to monitor aircraft and vehicle movements into and out of these blocks. The system then indicates the block occupancy information for tower controllers on a two-dimensional (2-D) display of an airport map. This surveillance information is envisioned to improve controller situational awareness of surface operations, particularly in reduced visibility.

关键词： Aircraft Surveillance Airports Magnetometers Aerospace control Magnetic sensors

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Developing an onboard traffic-aware flight optimization capability for near-term low-cost implementation

Developing an onboard traffic-aware flight optimization capa...

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2013 aviation Technology, Integration, and Operations Conference

作者： Wing, David J. Balin, Mark G. Koczo Jr., Stefan Vivona, Robert A. Henderson, Jeffrey M. Crew Systems and Aviation Operations NASA Langley Research Center Mail Stop 152 Hampton VA 23681 United States NASA Langley Research Center NASA NextGen Concepts and Technology Development Project Mail Stop 156A Hampton VA 23681 United States Rockwell Collins Inc Advanced Technology Center Cedar Rapids IA 52498 United States ATRE Department Engility Corporation 300 Concord Road Billerica MA 01821 United States

ISBN: (纸本)9781624102257

The concept of Traffic Aware Strategic Aircrew Requests (TASAR) combines Automatic Dependent Surveillance Broadcast (ADS-B) IN and airborne automation to enable user-optimal in-flight trajectory replanning and to increase the likelihood of Air Traffic Control (ATC) approval for the resulting trajectory change request. TASAR is designed as a near-term application to improve flight efficiency or other user-desired attributes of the flight while not impacting and potentially benefiting ATC. Previous work has indicated the potential for significant benefits for each TASAR-equipped aircraft. This paper will discuss the approach to minimizing TASAR's cost for implementation and accelerating readiness for near-term implementation.

关键词： Air traffic control

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