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This paper discusses the fundamentals of architecting a major human spaceflight program and some of the lessons that can be learned from NASA's Constellation Program. This paper describes the Constellation program, whose primary objective focuses on development of a new generation of vehicles and systems to enable human exploration beyond Earth orbit. Constellation is made up of seven projects that are highly interdependent and is referred to in the NASA management system as a “tightly coupled” program. This paper will discuss the driving architectural priorities and characteristics for human exploration missions beyond earth orbit and how its building blocks are developed through initial capability missions to the International Space Station. The systems engineering challenges of simultaneously defining and developing systems that are interdependent will be discussed.

A brief explanation of the design iterations and philosophy used to integrate the pilot into the F-35 Lightning II cockpit to achieve optimum Pilot Vehicle Interface (PVI), manageable single seat workload, and superior situation awareness.

Electrification of the automobile is a growing trend and will create both challenges and opportunities for the vehicle manufacturer, road network infrastructure and driver. In addition to innovative fundamental battery and power transfer technologies, electric vehicles will integrate unique driver interfaces, road intelligence, traffic awareness and wireless data communication to provide a complete support system. This networked vehicle will improve efficiency, increase cruising range and contribute to the overall driving enjoyment of an electric or plug-in hybrid-electric vehicle. Through tailored applications created by content and service providers the driver will identify the most efficient travel routes, learn efficient driving behaviors, avoid energy-wasting situations, locate charging stations and have confidence in reaching a destination and returning home.

In the last few years, almost every automotive OEM has announced the development of some sort of electric vehicles. Many of those have already been shown to the public, either as concept vehicles, or as pre-production demonstration vehicles. In order to support the development of this technology, FEV has, over the last 18 months, developed more than 20 different electric, or range-extended electric vehicles. All those vehicles are driving successfully on the road today, either as demonstration or fleet vehicles. The development of those vehicles was only possible through partnerships, and very close cooperation with key suppliers. In contrast to conventional powertrain technology, key components (e.g. battery, traction motor, electric HVAC, inverters) are not yet off-the-shelf technology and need further development and adaptation to the new vehicle concepts.

Whether it be in highly visible features like fascinating new infotainment systems or hidden behind the scenes in complex new hybrid powertrain controls, in-vehicle software is rapidly changing the way the automotive industry engages its vehicle-buying customers. In every application where a compelling new electronic solution is emerging, it is enabled by the convergence of in-vehicle software developed by different collaborating partners. As more and more component suppliers, vehicle OEMs, and technology vendors enter into collaborative software development projects with each other, a new set of technical and business challenges are showing collaborative software development to be a very distinctive proposition than traditional stand-alone development.

MIL-STD-704 defines power quality in terms of transient, steady-state, and frequency-domain metrics that are applicable throughout a military aircraft electric power system. Maintaining power quality in more electric aircraft power systems has become more challenging in recent years due to the increase in load dynamics and power levels in addition to stricter requirements of power system characteristics during a variety of operating conditions. Further, power quality is often difficult to assess directly during experiments and aircraft operation or during data post-processing for the integrated electric power system (including sources, distribution, and loads). While MIL-STD-704 provides guidelines for compliance testing of electric load equipment, it does not provide any instruction on how to assess the power quality of power sources or the integrated power system itself, except the fact that power quality must be satisfied throughout all considered operating conditions.

In order to satisfy a single-fuel mandate, the U.S. Department of Defense has a need for engines in the 20 to 50 hp range to power midsized Unmanned Aerial Vehicles (UAVs) and the ability to operate on JP-8 also known as “heavy” fuel. It is possible to convert two-stroke aircraft engines designed to operate on a gasoline-oil mixture to run on JP-8/oil using the Sonex Combustion System (SCS) developed by Sonex Research, Inc. Conversion of the engine involves replacing the cylinder heads with new components designed to accept a steel combustion ring insert. Also required are glow-plugs to preheat the cylinder head prior to engine start. The converted engine produces the same power output as the stock engine operating on gasoline. Conversion of both a 20 hp and 40 hp engine was successfully achieved using the SCS.

Increasing electronic controls in aircraft flight deck, especially in military aircrafts, demands special attention from crew workload assessment and human error analysis point of view. The main objective for the Authority is to validate that the crew workload is adequate for different and complicated military missions. Besides, human error analysis is a regulatory requirement in Airworthiness Certification of airplanes. Human errors need to be observed during simulated operational use of novelties and analyzed later (during the debriefing with pilots or during the results analysis). The main objective during the debriefing is to identify their causes, their consequence, their criticality and the current safety barriers in terms of human errors management. Simulators offer wide range of capability to identify the problems in early stages of the design. Degree of fidelity needed on evaluation media is related with the complexity of the military mission and project budget.

In Chemistry “Inert” implies ‘not readily reactive with other elements; forming few or no chemical compounds or something that is not chemically active’. “Inerting” is the process that renders a substance inert. A method for making a fuel-tank inert without the use of an inert gas is described. In this method fuel-air ratio of ullage is reduced until it becomes inert. The method does not discharge fuel vapors as an inert gas inerting system. Two systems employing the method are described explaining their pros and cons. Advantages of the method over Nitrogen Enriched Air (NEA) inerting method with an On-board Inert Gas Generating System (OBIGGS) are discussed. Patent application on the method and system is pending.

Boeing has contracts for military application of twin engine airplanes generically identified in this paper as the MX airplane. Unlike previous derivatives, the MX airplanes are produced with a streamlined manufacturing process to improve cost and schedule performance. The final assembly of each MX airplane includes a series of integration tests, called factory functional tests (FFTs), which are modified from those of typical commercial versions and verify correctness of equipment installation and basic functionalities. Two airplanes have been through the production line resulting in a number of FFT lessons learned. Addressed are the power distribution lessons learned: 1) the expanded coverage of the basic automated power-on generation system test, 2) the need for a manual wire continuity test, 3) salient features of the power distribution tests, and 4) keys to make first pass power distribution test smooth and successful.

Extended-duration space missions entailing expanded crew sizes and activities will produce a need for habitats that combine advantages of conventional hard/fixed and soft/deployable structures. Rigid modules enable pre-integration of utility and equipment systems prior to launch and apply proven technologies. Soft pressure vessels can be compacted to optimize launch payload volume and habitable volume/mass efficiencies, but impose hardware integration challenges, operational readiness requirements, and long-term structural performance uncertainties. This paper discusses concepts and applications that incorporate both approaches. Examples draw upon research and design investigations undertaken by SICSA in support of a NASA-sponsored study conducted by two independent teams, one headed by Boeing, and the other by ILC-Dover. SICSA had key roles in developing overall configuration architectures for both teams.

A future car-to-x communication system has to fulfil a lot of different requirements concerning high performance and functionality that are given by the field of application. To be able to optimize the system architecture regarding these constraints an intensive architecture evaluation and investigation is necessary. Within this paper a simulative approach for comprehensive design space exploration, verification, and test of a car-to-x communication unit is presented. The proposed simulation environment allows for a flexible adaption to the test case by being able to interconnect an arbitrary number of simulators of different type and different granularity. As a novelty complete embedded car-to-x systems can be investigated by integrating several SystemC based architecture models into an environmental simulation and observing their behavior and interaction.

Due to a rapid development of air transportation there is a need for the assessment of real environmental risk related to the aircraft operation. The emission of carbon monoxide and particulate matter is still a serious threat~constituting an obstacle in the development of combustion engines. The applicable regulations related to the influence of the air transportation on the environment introduced by EPA (Environmental Protection Agency), ICAO (International Civil Aviation Organization) contained in JAR 34 (JAA, Joint Aviation Requirements, JAR 34, Aircraft Engine Emissions), FAR 34 (FAA, Federal Aviation Regulations, Part 34, Fuel Venting and Exhaust Emission Requirements for Turbine Engine Powered Airplanes), mostly pertain to the emission of noise and exhaust gas compounds, NOx in particular. They refer to jet engines and have stationary test procedures depending on the engine operating conditions.

The riveting process with a solid rivet is one of the most applied joining processes in the aeronautic industry. New materials and new design requirements constitute challenges that drive the users to a better understanding of the installation process of riveted joints. Therefore, this study aims with the aid of FEM simulation to understand the phenomena occurring during the installation process and afterwards to predict the mechanical properties of the riveted joint depending on the installation parameters and characteristics of the adherends. The experimental installation process for the validation of the simulation model takes place in a fully automated C-frame riveting machine with all-electric drilling and riveting operations aptitude and continuous collection of process data. This paper deals with the simulation of the installation process. The simulation model consists of a solid rivet with universal head described by the standard EN6081 and aluminum (2024-T351) adherends.

Serial link articulated robots applied in aerospace assembly have largely been limited in scope by deficiencies in positional accuracy. The majority of aerospace applications require tolerances of +/−0.25mm or less which have historically been far beyond reach of the conventional off-the-shelf robot. The recent development of the accurate robot technology represents a paradigm shift for the use of articulated robotics in airframe assembly. With the addition of secondary feedback, high-order kinematic model, and a fully integrated conventional CNC control, robotic technology can now compete on a performance level with customized high precision motion platforms. As a result, the articulated arm can be applied to a much broader range of assembly applications that were once limited to custom machines, including one-up assembly, two-sided drilling and fastening, material removal, and automated fiber placement.

Titanium is a difficult material to fabricate into complex configurations. There is several elevated temperature forming processes available to produce titanium components for aerospace applications. The processes to be discussed are Superplastic Forming (SPF), hot forming and creep forming. SPF uses a tool that contains the required configuration and seals around the periphery so inert gas pressure can be used to form the material. Of the processes to be discussed, this is the one that can produce the most complex shapes containing the tightest radii. A variation of the process combines an SPF operation with diffusion bonding (SPF/DB) of two or more pieces of titanium together to produce integrally stiffened structure containing very few fasteners. Another process for shaping titanium is hot forming. In this process, matched metal tools, offset by the thickness of the starting material, are used to form the part contour at elevated temperature.

Once limited by insufficient accuracy, the off-the-shelf industrial robot has been enhanced via the integration of secondary encoders at the output of each of its axes. This in turn with a solid mechanical platform and enhanced kinematic model enable on-part accuracies of less than +/−0.25mm. Continued development of this enabling technology has been demonstrated on representative surfaces of an aircraft fuselage. Positional accuracy and process capability was validated in multiple orientations both in upper surface (spindle down) and lower surface (spindle up) configurations. A second opposing accurate robotic drilling system and full-scale fuselage mockup were integrated to simulate doubled throughput and to demonstrate the feasibility of maintaining high on-part accuracy with a dual spindle cell.

A two machine Automated Fiber Placement (AFP) cell capable of laying 1/2\mi and 1/4\mi tow at rates up to 1800\mi/min (45.7 m/min), including feeds and cuts, has been implemented for the manufacture of large primary aircraft structures. The control architecture of the cell is such that part programs are machine independent and can run on either machine or simultaneously on both machines at the same time. A Central Cell Controller pushes part programs to each AFP machine and coordinates the cell. Volumetric accuracy of the two machines is under 0.008\mi (0.2 mm) radial error in the entire compensated envelop, which is approximately 64' x 21' x 14' (19.5 m x 6.4 m x 4.3 m) for each machine. This is accomplished through optimization of volumetric kinematic compensation parameters using a linear numerical solver. The machines reference a common coordinate system which allows great flexibility in part programming.

A chemical vapor deposition method for preparing high-quality chromium carbide coatings was developed. The resulting coatings exhibit high adhesion and increase wear resistance of the cylinder piston group components as compared to common coatings prepared by electrolytic chromium plating. The operation performance of the coatings was tested using scrapper piston of the Raba-Man diesel engine of Ikarus bus and compression and oil scrapper rings of the diesel engine 10D100. It was found that chromium coatings prepared by the method proposed are characterized by relatively low coefficient of friction and high corrosion resistance.

For most car manufacturers, wind noise from the greenhouse region has become the dominant high frequency noise contributor at highway speeds. Addressing this wind noise issue using experimental procedures involves high cost prototypes, expensive wind tunnel sessions, and potentially late design changes. To reduce the associated costs as well as development times, there is strong motivation for the use of a reliable numerical prediction capability early in the vehicle design process. Previously, a computational approach that couples an unsteady computational fluid dynamics solver (based on a Lattice Boltzmann method) to a Statistical Energy Analysis (SEA) solver had been validated for predicting the noise contribution from the side mirrors. This paper presents the use of this computational approach to predict the vehicle interior noise from the windshield wipers, so that different wiper placement options can be evaluated early in the design process before the surface is frozen.