A mathematical model of a tilt-wing aircraft for piloted simulation

A mathematical model of a tilt-wing aircraft that was used in a piloted, six-degree-of-freedom flight simulation application is described. Two types of control systems developed for the math model are discussed: a conventional, programmed-flap wing-tilt control system and a geared-flap wing-tilt control system. The primary objective was to develop the capability to study tilt-wing aircraft. Experienced Tilt-wing pilots subjectively evaluated the model using programmed-flap control to assess the quality of the simulation. The math model was then applied to study geared-flap control to investigate the possibility of eliminating the need for auxilary pitch-control devices (such as the horizontal tail rotor or tail jet used in earlier tilt-wing designs). This investigation was performed in the moving-base simulation environment, and the vehicle responses with programmed-flap and geared-flap control were compared. The results of the evaluation of the math model are discussed

Control of a human-powered helicopter in hover

The study of a control system for the Da Vinci 2 human-powered helicopter in hovering flight is documented. This helicopter has two very large, slowly rotating rotor blades and is considered to be unstable in hover. The control system is designed to introduce stability in hover by maintaining level rotors through the use of rotor tip mounted control surfaces. A five degree of freedom kinematic model was developed to study this control system and is documented. Results of this study show that the unaugmented configuration is unstable due to the large Lock Number, and the augmented configuration is stable. The role of NASA in this study included the development and analysis of the kinematic model and control laws. Both analytical and numerical techniques were used

Rotor and control system loads analysis of the XV-15 with the advanced technology blades

An analysis of the rotor and control system loads of the XV-15 with the Advanced Technology Blades (XV-15/ATB) was conducted to study the effects of modifications designed to alleviate high collective actuator loads encountered during initial flight tests. Rotor loads predictions were correlated with flight data to establish accuracies of the methodology used in the analysis. Control system loads predictions were then examined and were also correlated with flight data. The results showed a significant reduction in 3/rev collective actuator loads of the XV-15/ATB when the control system stiffness was increased and the rotor blade chord balance and tip twist were modified

Aerodynamic Analysis of the Truss-Braced Wing Aircraft Using Vortex-Lattice Superposition Approach

The SUGAR Truss-BracedWing (TBW) aircraft concept is a Boeing-developed N+3 aircraft configuration funded by NASA ARMD FixedWing Project. This future generation transport aircraft concept is designed to be aerodynamically efficient by employing a high aspect ratio wing design. The aspect ratio of the TBW is on the order of 14 which is significantly greater than those of current generation transport aircraft. This paper presents a recent aerodynamic analysis of the TBW aircraft using a conceptual vortex-lattice aerodynamic tool VORLAX and an aerodynamic superposition approach. Based on the underlying linear potential flow theory, the principle of aerodynamic superposition is leveraged to deal with the complex aerodynamic configuration of the TBW. By decomposing the full configuration of the TBW into individual aerodynamic lifting components, the total aerodynamic characteristics of the full configuration can be estimated from the contributions of the individual components. The aerodynamic superposition approach shows excellent agreement with CFD results computed by FUN3D, USM3D, and STAR-CCM+

Mobile Mapping and its Potential for Faculty Collaboration and Undergraduate Student Learning

Undergraduate research is a high impact practice for student learning, but the key is often to match projects with tools that build students’ skills as they learn about a topic. Digital tools now profligate to the point that they are almost overwhelming to the student and teacher alike. These tools, coupled with computing have forged an entirely new field: digital humanities. Our manuscript discusses how one easy to use, student friendly digital tool—ARCGIS’s mobile app, Collector—is used in collaborative undergraduate research. The tool’s usefulness stems from its potential to contribute to the relationship between the discourse on digital humanities with its actual practice in the classroom. The Collector App encourages undergraduate researchers to go beyond the confines of the classroom and into the field to conduct research with one of their favorite tools, their smartphone. The Collector App allows past-present-and future classes of students to intermingle in a digital space that is devoted to creating knowledge for public use. The easy-to-use digital tool facilitates undergraduates in the Humanities and other disciplines to become cognizant of the world immediately around them in a new way while also equipping them with a technical skill that may be applied in other courses as well as in future employment scenarios. In short, the Collector App serves as a place where applied research and the scholarship of discovery intersect. As such, the Collector App contributes to the expansion of the digital humanities into undergraduate education. We present as evidence several different collaborative digital undergraduate projects that span classes and semesters and all involve primary field research through Collector. The Collector-based research projects have encouraged students to build skills while contributing to knowledge in new ways.La recherche de premier cycle est une pratique à fort impact sur l'apprentissage des étudiants, mais la clé est souvent de trouver des outils qui renforcent les compétences des étudiants tout en apprenant sur un sujet donné. Les outils numériques sont maintenant si présents qu'ils sont presque écrasants tant pour les élèves que pour les enseignants. Ces outils, associés à l'informatique, ont forgé un tout nouveau domaine : les sciences humaines numériques. Notre manuscrit explique la façon dont un outil numérique facile à utiliser et convivial pour les étudiants — l'application mobile d'ARCGIS, Collector — est utilisé dans la recherche collaborative dans le premier cycle universitaire. L'utilité de l'outil découle de son potentiel à contribuer à la relation entre le discours sur les sciences humaines numériques et sa pratique réelle en classe. Le Collector App encourage les chercheurs de premier cycle à sortir des limites de la salle de classe et à se rendre sur le terrain pour mener des recherches avec l'un de leurs outils préférés, leur téléphone portable mobile. L'application Collector permet aux anciennes et futures classes d'élèves de se mêler dans un espace numérique dédié à la création de connaissances à usage public. Cet outil numérique facile à utiliser permet aux étudiants de premier cycle en sciences humaines et dans d'autres disciplines de se familiariser avec le monde qui les entoure immédiatement et de façon nouvelle tout en acquérant une compétence technique qui pourra être utilisée dans d'autres cours ainsi que dans de futurs scénarios professionnels. En résumé, l'application Collector sert de lieu d'intersection entre la recherche appliquée et la découverte scientifique. À ce titre, l'application Collector App contribue à l'expansion des sciences humaines numériques dans l'enseignement de premier cycle. Nous présentons comme preuve plusieurs projets de collaboration de premier cycle en numérique qui s'étendent sur plusieurs classes et semestres et qui impliquent tout une recherche primaire sur le terrain par le biais de Collector

An Integrated Vehicle Modeling Environment

This paper describes an Integrated Vehicle Modeling Environment for estimating aircraft geometric, inertial, and aerodynamic characteristics, and for interfacing with a high fidelity, workstation based flight simulation architecture. The goals in developing this environment are to aid in the design of next generation intelligent fight control technologies, conduct research in advanced vehicle interface concepts for autonomous and semi-autonomous applications, and provide a value-added capability to the conceptual design and aircraft synthesis process. Results are presented for three aircraft by comparing estimates generated by the Integrated Vehicle Modeling Environment with known characteristics of each vehicle under consideration. The three aircraft are a modified F-15 with moveable canards attached to the airframe, a mid-sized, twin-engine commercial transport concept, and a small, single-engine, uninhabited aerial vehicle. Estimated physical properties and dynamic characteristics are correlated with those known for each aircraft over a large portion of the flight envelope of interest. These results represent the completion of a critical step toward meeting the stated goals for developing this modeling environment

Multimodal Neuroelectric Interface Development

This project aims to improve performance of NASA missions by developing multimodal neuroelectric technologies for augmented human-system interaction. Neuroelectric technologies will add completely new modes of interaction that operate in parallel with keyboards, speech, or other manual controls, thereby increasing the bandwidth of human-system interaction. We recently demonstrated the feasibility of real-time electromyographic (EMG) pattern recognition for a direct neuroelectric human-computer interface. We recorded EMG signals from an elastic sleeve with dry electrodes, while a human subject performed a range of discrete gestures. A machine-teaming algorithm was trained to recognize the EMG patterns associated with the gestures and map them to control signals. Successful applications now include piloting two Class 4 aircraft simulations (F-15 and 757) and entering data with a "virtual" numeric keyboard. Current research focuses on on-line adaptation of EMG sensing and processing and recognition of continuous gestures. We are also extending this on-line pattern recognition methodology to electroencephalographic (EEG) signals. This will allow us to bypass muscle activity and draw control signals directly from the human brain. Our system can reliably detect P-rhythm (a periodic EEG signal from motor cortex in the 10 Hz range) with a lightweight headset containing saline-soaked sponge electrodes. The data show that EEG p-rhythm can be modulated by real and imaginary motions. Current research focuses on using biofeedback to train of human subjects to modulate EEG rhythms on demand, and to examine interactions of EEG-based control with EMG-based and manual control. Viewgraphs on these neuroelectric technologies are also included

Les humanités numériques dans une perspective internationale : opportunités, défis, outils et méthodes

Ce numéro de la revue ILCEA se propose d’offrir un aperçu de projets de recherche rendus possibles par une intégration du numérique dans diverses disciplines SHS et aires géographiques, mais aussi de faire état des questionnements des chercheurs qui y ont eu recours, des solutions qu’ils ont mises en place afin de mener à bien leurs travaux et de pistes de réflexion pour l’avenir sur ce terrain encore largement exploratoire. This issue of the ILCEA journal aims to provide an overview of projects made possible by the integration of digital technology in various disciplines of the humanities and geographical areas, but also to report on the questions raised by the researchers who have used it, the solutions they have implemented in order to carry out their work, and the avenues for future reflection in this field, which is still largely exploratory