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The aim of this work is to apply an innovative adaptive ℒ1 techniques to control flutter phenomena affecting highly flexible wings and to evaluate the efficiency of this control algorithm and architecture by performing the following tasks: i) adaptation and analysis of an existing simplified nonlinear plunging/pitching 2D aeroelastic model accounting for structural nonlinearities and a quasi-steady aerodynamics capable of describing flutter and post-flutter limit cycle oscillations, ii) implement the ℒ1 adaptive control on the developed aeroelastic system to perform initial control testing and evaluate the sensitivity to system parameters, and iii) perform model validation and calibration by comparing the performance of the proposed control strategy with an adaptive back-stepping algorithm. The effectiveness and robustness of the ℒ1 adaptive control in flutter and post-flutter suppression is demonstrated.

To a large degree all of us at one time or another have envisioned our “Over the Rainbow” version of a future should be. System engineers envision perfect harmony between vehicle aerodynamics and avionics integration. The program manager dreams of schedules and funding well within the projected budget. Then reality; budget constraints, backward compatibility, technology availability, schedule problems, and etc. This paper is intended to recognize the “dreamer” and at the same time offer a means of reconciliation to the real world. We will address advanced avionics architectures and a transitionary means to attain our goals and objectives. An “Avionics System Index” will be presented which defines and specifies a means of describing and partitioned avionics configuration.

Mathematical modeling and control of artificial ecosystems, such as MELISSA, require first the study of physical and biological characteristics in optimal and limiting conditions. Following the previous determination of the stoichiometric equations (Spirulina compartment) and regarding the two phototrophic compartments of MELISSA (Rhodospirillaceae and Spirulina), we have first to focus our control study on the growth kinetics for the light source. In this paper, we recall the theoretical equations of microbial growth kinetics and emphasise the problem of the light transfer in a photobioreactor. We present their adaptations to our pilot plant taking into account technological and biological specifics (lamp spectrum, working illuminated volume, growth rate,…). We then develop the principles and structure of the control system and describe tests of both the hardware and software for several steady state configurations.

The requirement for crew resource management (CRM), or aircrew coordination training (ACT) in military parlance, has been well documented and attested to. In addition, aircraft systems training has become more intense and more in-depth in the new aircraft designs, especially in multi-crew and complex aircraft such as the MV-22 Osprey Tiltrotor. (see Figure 1) Former training systems detailed training procedures that called for classroom training and simulation/simulator training followed by flight training. Improvements in aircraft flight skills training provide increased flying training capability coupled with reduced training time by integrating a mixed simulation/flight training syllabus, e.g. two to three simulation periods followed by one or two flight training periods covering the same material/skills. In addition, the simulation training will introduce new skills; the following flight periods will further refine/hone those skills.

The euces project was initiated to be prepared for the future role of EADS as stage system prime for stage and launcher developments. Launcher stages for NGLV need to meet ambitious mission and operational demands. The paper will present a brief overview of the currently existing COMPONENT libraries and its possibilities as well as an application example which will be a simplified functional model of the ARIANE 5 EPS upper stage w.r.t. physical model formulation of its incorporated components, its schematic, data initialisation and simulation results obtained. The simulation results will be compared to flight data of a dedicated flight.

This paper discusses the findings for [Interior] Configuration Options, Habitability and Architectural Aspects of a first human spacecraft to Mars. In 2003 the space architecture office LIQUIFER was invited by the European Space Agency’s (ESA) AURORA program committee to consult the scientists and engineers from the European Space and Technology Center (ESTEC) and other European industrial communities with developing the first human mission to Mars, which will take place in 2030, regarding the architectural issues of crewed habitats. The task was to develop an interior configuration for a Transfer Vehicle (TV) to Mars, especially a Transfer Habitation Module (THM) and a Surface Habitat (SHM) on Mars. The total travel time Earth - Mars and back for a crew of six amounts to approximately 900 days. After a 200-day-flight three crewmembers will land on Mars in the Mars Excursion Vehicle (MEV) and will live and work in the SHM for 30 days.

A “next generation” condensing heat exchanger for space systems has to satisfy demanding operational requirements under variable thermal and moisture loads and reduced gravity conditions. Mathematical models described here are used to investigate transient behavior of wetting and de-wetting dynamics in the binary porous system of porous tubes and porous cold plate. The model is based on the Richard's equation simplified for the zero-gravity conditions. The half-saturation distance or the zone of influence of the porous annular suction tubes on the cold-plate porous material will be in the range of 1 to 10 cm for the time scales ranging from 100 to 10,000 seconds and moisture diffusivity in the range of D = 10-4 to 10-6 m2/s.

For human beings who have been reared on the earth with its 1 G gravitational field, the condition of weightlessness is a world with which we are unfamiliar. Even if the layout and equipment configuration of a spacecraft designed to compensate for operation under Zero-G conditions, there are some things which are not effective under actual weightless conditions. In the design of a manned spacecraft, it is necessary to accumulate design data on human performance in a weightless condition, then to undertake design evaluations and verification under weightless conditions. In this paper, testing for the purpose of evaluating the effectiveness of Zero-G simulation using neutral buoyancy, conducted first of all in Japan, and recommendations on the equipment and Facilities required to conduct such simulations, are described.

Zero trust (ZT) is an emerging initiative that focuses on securely providing access to resources based on defined policies. The core tenet of ZT is “never trust, always verify”, meaning that even within trusted zones of operation, resource access must be explicitly granted. ZT has proven effective in improving the security posture in domains such as information technology infrastructure; however, additional research and development is needed to define and apply zero trust principles to cyber-physical system domains. To work toward this objective, we have identified an initial set of ZT architectural patterns targeted specifically at cyber-physical systems. We created ZT architecture patterns in the Architecture Analysis and Design Language (AADL), a modeling language that enables engineers to describe the key elements of embedded system architectures using a well-defined semantics.

This paper describes the development of a set of algorithms that find the takeoff gross weight of an aircraft for given vehicle and engine characteristics, and mission requirements. A major objective was to find the most elementary set that would still yield useful answers. The result was a set that could be encoded on an inexpensive programmable pocket calculator with only 24 lines of code. Results are compared with actual characteristics of an executive jet and its derivative versions.

XM Satellite Radio launched its nationwide service in September of 2001. With 6.5 million subscribers at the end of the first quarter of 2006, XM is one of the fastest growing audio formats and entertainment services. This paper addresses XM's technology and content evolution, primarily for the radio unit and the signaling protocols, from the early years to the present time, and the applicability of this technology in fostering exciting new infotainment services. The radio architecture includes an antenna, an RF tuner module, a baseband chipset and a microprocessor. All of these subsystems underwent a complete transformation in the past four years from a size perspective, capability and cost. Specifically the following phases of the radio platform are addressed: a) Phase 1: The early years; b) Phase 2: The invention of the Plug and Play ; c) Phase 3: Connect and Play ; d) Phase 4; The wearable; e) Phase 5: Infotainment convergence of audio plus data services.

The X-36 is a remotely piloted 28% scale model of a two-axis-unstable notional future fighter aircraft with canards, a mid-wing and features the absence of any vertical control surfaces, Figure 1. The aircraft was jointly developed by the NASA Ames Research Center and McDonnell Aircraft & Missile Systems and flight tested at the NASA Dryden Flight Research Center. Objectives of this program were to demonstrate fighter aircraft agility for a vertical tailless configuration and to demonstrate the development of a low cost alternative to full size prototype aircraft. This paper presents some aspects of the subsystem integration methodology used to develop the X-36 Tailless Agility Research Aircraft.

It was anticipated that during X-29 extended duration, high angle-of-attack flight (40 to 70 deg), aircraft ECS performance would significantly degrade. Computer modelling of the system indicated that the performance of the ECS decreased as the angle of attack increased. Modifications to improve system performance were analyzed and, as a result of this analysis, ECS hardware modifications have been incorporated on the aircraft. The High-Alpha Flight Test Program has proven the validity of these modifications. To date, the ECS on Ship No. 2 has performed well within its nominal operating parameters in the high-alpha regime.

Paralleling synchronous generators requires a priori voltage matching and frequency synchronization. Exceeding normal limits can lead to severe electrical transients. The classical three-phase short circuit analysis is extended to include the case of two initially unloaded synchronous generators. An analytical solution is developed neglecting winding resistances and saturation. Of particular interest is the tendency to induce negative field currents that cause inverse voltages across the rotating rectifier in a brushless design. Typical aircraft generator parameters are used to predict the paralleling transient vs. initial rotor electrical angle mismatch. Results are compared to simulation and limited test results.

One of the most unsolved problems in space projects, where human beings are involved, is the impossibility of simulating on the ground the effects of microgravity on astronauts' operability in space. [1] In particular, this is traceable in the performance of work activities, such as performing physiological scientific experiments. [2] This paper focuses on a study of the gap between the two operational scenarios: the ground test simulation and the in-flight space performance of complex physiological experiments. The major differences between the two operational scenarios are highlighted, and recommendations for improvement are suggested. The main finding of this paper is that, in order to make experiment performance not only possible but also easy and efficient, it is necessary to consider all human factors involved. With this perspective, the author's aim has been to find an effective way to consider all human factors of the ground and space operational conditions.

Currently, many factors influence the NASA Kennedy Space Center (KSC) workforce. These factors include the drive for return to flight, a Shuttle Program end date of 2010, and the Vision for Space Exploration which calls for the development of a new launch vehicle. Additionally, external factors exist as well, such as the area's cost of living, the availability of skilled resources, and the unemployment rate affect the overall workforce climate. To manage the human capital in a manner consistent with safety and mission success, and to strategically position NASA KSC to execute its future mission, it is necessary to understand how all of these different influencing factors work together to produce an overall workforce climate. We have been using System Dynamics models in order to capture some of these factors. These system dynamics models are also the starting point of agent-based models.

Relating to yet beyond the requirements of putting controls and displays at selected and selectable locations in the station, and to associated subsystem interfaces, is the ergonomic integration of these elements with the operator, and ALL with the diverse, proximal station architecture. Basic to optimal, long-term solutions to this integration is the requirement of the felicitous accommodation of a range of crew sizes from a 5% tile Asian female to a 95% tile Caucasian male. No less important is for the workstation's layout and architecture being optimized for the “new-shape-of-man” - the “neutral body position” - in weightlessness and with the associated geometry and dynamics of this significantly altered state, its capabilities and its new facility. This paper previews the on-going status, development and details of a body-ported workstation prototype and its semi stand-alone elements.

In order to provide effective cooling for astronauts during extravehicular activities (EVAs), a liquid cooling and ventilation garment (LCVG) is used to remove heat by a series of tubes through which cooling water is circulated. To better predict the effectiveness of the LCVG and determine possible modifications to improve performance, computer simulations dealing with the interaction of the cooling garment with the human body have been run using the Wissler Human Thermal Model. Simulations have been conducted to predict the heat removal rate for various liquid cooled garment configurations. The current LCVG uses 48 cooling tubes woven into a fabric with cooling water flowing through the tubes. The purpose of the current project is to decrease the overall weight of the LCVG system. In order to achieve this weight reduction, advances in the garment heat removal rates need to be obtained.

The aerospace industry is noticing significant shift towards More Electric Aircraft (MEA). The advancement of electrical technology the systems are being transformed towards electric compared to the conventional pneumatic or hydraulic systems. This has led to an increased demand in electrical power from 150 Kilo Watts in the conventional airplane to 1 Mega Watts in More Electric Aircraft. More electric systems, call for increased electrical wiring harness to connect various systems in the aircraft. These harnesses consist of power and data cables. Wireless communication technology is being matured for data communication, leading to reduction of wire harness for data. As of now, the length of wires in large commercial aircraft is over 100miles and it may not be surprising if the electrification of aircraft drive this too much longer.

This work falls in the context of aeronautical maintenance processes. The purpose is to increase the effectiveness and the efficiency of the operations carried out during the activities in the processes mentioned above, as well as the reduction of the incidence of the human error in the development of these activities, with consequent implicit increase of the safety of the aircrafts. Human error has been documented as a primary contributor to more than 70 percent of commercial airplane hull-loss accidents. While typically associated with flight operations, human error has also recently become a major concern in maintenance practices and air traffic management. We have tried to obtain an increment of the safety formalizing the information exchange process avoiding ambiguous, inaccurate or incomplete data that can indirectly encourage the deviation of the personnel from established procedures.