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As a result of recommendation from the Augustine Panel, the direction for Human Space Flight has been altered from the original plan referred to as Constellation. NASA's Human Exploration Framework Team (HEFT) proposes the use of a Shuttle Derived Heavy Lift Launch Vehicle (SDLV) and an Orion derived spacecraft (salvaged from Constellation) to support a new flexible direction for space exploration. The SDLV must be developed within an environment of a constrained budget and a preferred fast development schedule. Thus, it has been proposed to utilize existing assets from the Shuttle Program to speed development at a lower cost. These existing assets should not only include structures such as external tanks or solid rockets, but also the Flight Software which has traditionally been a ?long pole? in new development efforts. The avionics and software for the Space Shuttle was primarily developed in the 70's and considered state of the art for that time.

The knock metric for controlled auto-ignition (CAI) engines is assessed by considering the physical processes that establish the pressure wave that contributes to the acoustic radiation of the engine, and by analyzing pressure data from a CAI engine. Data sets from the engine operating with port fuel injection, early direct injection and late direct injection are used to monitor the effect of mixture composition stratification. Thermodynamic analysis shows that the local pressure rise produced by heat release has to be discounted by the work spent in acoustic expansion against the ambient pressure to properly predict the pressure wave amplitude. Based on this analysis, a modified correlation between the pressure wave amplitude and the maximum pressure rise rate (MPRR) is developed by introducing an MPRR offset to account for the expansion work.

The engine and its exhaust flow behaviors are investigated in a turbo-charged gasoline direct injection engine under simulated cold-fast-idle condition. The metrics of interest are the exhaust sensible and chemical enthalpy flows, and the exhaust temperature, all of which affect catalyst light off time. The exhaust sensible enthalpy flow is mainly a function of combustion phasing; the exhaust chemical enthalpy flow is mainly a function of equivalence ratio. High sensible and chemical enthalpy flow with acceptable engine stability could be obtained with retarded combustion and enrichment. When split injection is employed with one early and one later and smaller fuel pulse, combustion retards with early secondary injection in the compression stroke but advances with late secondary injection. Comparing gasoline to E85, the latter produces a lower exhaust temperature because of charge cooling effect and because of a faster combustion.

The performance enhancement of a vertical tail provided by aerodynamic flow control could allow for the size of the tail to be reduced while maintaining similar control authority. Decreasing tail size would create a reduction in weight, drag, and fuel costs of the airplane. The application of synthetic jet actuators on improving the performance of the vertical tail was investigated by conducting experiments on 1/9th and 1/19th scale wind tunnel models (relative to a Boeing 767 tail) at Reynolds numbers of 700,000 and 350,000, respectively. Finite-span synthetic jets were placed slightly upstream of the rudder hinge-line in an attempt to reduce or even eliminate the flow separation that commences over the rudder when it was deflected to high angles. Global force measurements on the 1/9th scale model showed that the flow control is capable of increasing side force by a maximum of 0.11 (19%). The momentum coefficient that created this change was relatively small (Cμ = 0.124%).

Minimizing the stress concentrations around cutouts in a plate is often a design problem, especially in the Aerospace industry. A problem of optimizing spatially varying fiber paths in a symmetric, linear orthotropic composite laminate with a cutout, so as to achieve minimum stress concentration under remote unidirectional tensile loading is of interest in this study. A finite element (FE) model is developed to this extent, which constraints the fiber angles while optimizing the fiber paths, proving essential in manufacturing processes. The idea to be presented could be used to derive fiber paths that would drastically reduce the Stress Concentration Factor (SCF) in a symmetric laminate by using spatially varying fibers in place of unidirectional fibers. The model is proposed for a four layer symmetric laminate, and can be easily reproduced for any number of layers.

The effects of secondary air on the exhaust oxidation of particulate matters (PM) have been assessed in a direct-injection-spark-ignition engine under fuel rich fast idle condition (1200 rpm; 2 bar NIMEP). Substantial oxidation of the unburned feed gas species (CO and HC) and significant reduction of both the particulate number (up to ∼80%) and volume (up to ∼90%) have been observed. The PM oxidation is attributed to the reactions between the PM and the radicals generated in the oxidation of the feed gas unburned species. This hypothesis is supported by the observation that the reduction in PM volume is proportional to the amount of heat release in the secondary oxidation.

Over 1,200 large diameter holes must be drilled into the side-of-body join on a Boeing commercial aircraft's fuselage. The material stack-ups are multiple layers of primarily titanium and CFRP. Due to assembly constraints, the holes must be drilled for one-up-assembly (no disassembly for deburr). In order to improve productivity, reduce manual drilling processes and improve first-time hole quality, Boeing set out to automate the drilling process in their Side-of-Body join cell. Implementing an automated solution into existing assembly lines was complicated by the location of the target area, which is over 15 feet (4 meters) above the factory floor. The Side-of-Body Drilling machines (Figure 1) are capable of locating, drilling, measuring and fastening holes with less than 14 seconds devoted to non-drilling operations. Drilling capabilities provided for holes up to ¾″ in diameter through stacks over 4.5″ thick in a titanium/CFRP environment.

The Efficient Assembly, Integration & Test (EAIT) team at Boeing Research & Technology, Boeing's central technology organization, is working on multiple implementations of Augmented Reality to aid assembly at the satellite production facility in El Segundo, CA. This presentation will discuss our work to bring an Augmented Reality tool to the shop floor, integrating product design and manufacturing techniques into a synergistic backbone and how this approach can support the delivery of engineering design intent on the shop floor. The team is developing a system to bring designer's 3D CAD models to the technicians on the shop floor, and spatially register them to live camera views of production hardware. We will discuss our work in evaluating multiple motion captures systems, how we integrated a Vicon system with Augmented Reality software, and our development of a user interface allowing technicians to manipulate the graphical display.

Electroimpact and Boeing are improving the efficiency and reliability of the Boeing 777 spar assembly process. In 1992, the Boeing 777 spar shop installed Giddings and Lewis spar machines with Electroimpact Inc. EMR(1) (Electromagnetic Riveting) technology. In 2011, Electroimpact Inc. began replacing the original spar machines with next generation assembly machines. The new carriages incorporate a number of technical improvements and advancements over the current system. These technical advancements have facilitated a 50% increase in average cycle rate, as well as improvements to overall process efficiency, reliability and maintainability. Boeing and Electroimpact have focused on several key technology areas as opportunities for significant technical improvements.

Passenger cars in the United States continue to incorporate increasing levels of technology and features. However, deployment of technology requires substantial development and time in the automotive sector. Prior analyses indicate that deployment of technology in the automotive sector can be described by a logistic function. These analyses refer to maximum annual growth rates as high as 17% and with developmental times of 10-15 years. However, these technologies vary widely in complexity and function, and span decades in their implementation. This work applies regression with a logistic form to a wide variety of automotive features and technologies and, using secondary regression, identifies broader trends across categories and over time.

Since the 1960's, lightning protection of aircraft has been an important design aspect, a concern for the flying public, aircraft manufacturers and the Federal Aviation Administration (FAA). With the implementation of major aircraft structures fabricated from carbon fiber reinforced plastic (CFRP) materials, lightning protection has become a more complicated issue to solve. One widely used material for lightning strike protection of CFRP structures within the aerospace industry is expanded metal foil (EMF). EMF is currently used in both military and commercial passenger aircraft. An issue that has historically been an area of concern with EMF is micro cracking of paint on the composite structure which can result in corrosion of the metal foil and subsequent loss of conductivity. This paper addresses the issues of stress and displacement in the composite structure layup which contribute to paint cracking caused by aircraft thermal cycling.

For urea Selective Catalytic Reduction (SCR) systems, adaptive control is of interest to provide a capability of maintaining high NOx conversion efficiency and low ammonia slip in the presence of uncertainties in the system. In this paper, the dynamics of the urea SCR system are represented by a control-oriented model which is based on a linear transfer function, with parameters dependent on engine operating conditions. The parameters are identified from input-output data generated by a high fidelity full chemistry model of the urea SCR system. The use of the full chemistry model facilitated the representation of the dynamics of stored ammonia (not a directly measurable parameter) as well as post SCR NOx and ammonia slip. A closed-loop Proportional-plus-Integral (PI) controller was first designed using the estimate of stored ammonia as a feedback signal.

Transport policy research seeks to predict and substantially reduce the future transport-related greenhouse gas emissions and fuel consumption to prevent negative climate change impacts and protect the environment. However, making such predictions is made difficult due to the uncertainties associated with the anticipated developments of the technology and fuel situation in road transportation, which determine the total fuel use and emissions of the future light-duty vehicle fleet. These include uncertainties in the performance of future vehicles, fuels' emissions, availability of alternative fuels, demand, as well as market deployment of new technologies and fuels. This paper develops a methodology that quantifies the impact of uncertainty on the U.S. transport-related fuel use and emissions by introducing a stochastic technology and fleet assessment model that takes detailed technological and demand inputs.

The Boeing Company under the teaming agreement with the Northrop Grumman Systems Corporation and in compliance with the NASA Phase 1 contract had the responsibilities for the CEV architecture development of the Environmental Control and Life Support (ECLS) system under the NASA Phase 1 contract. The ECLS system was comprised of the various subsystems which provided for a shirt-sleeve habitable environment for crew to live and work in the crew module of the CEV. This architecture met the NASA requirements to ferry cargo and crew to ISS, and Lunar sortie missions, with extensibility to long duration missions to Moon and Mars. This paper provides a summary overview of the CEV ECLS subsystems which was proposed in compliance with the contract activities.

Loping, defined here as skipping without a foot exchange, is a gait uncommonly used by humans on Earth, but favored by Apollo astronauts during lunar surface excursions. Astronauts may have adopted loping due to space suit-imposed mobility restrictions or because of a possible stability advantage conferred by a relatively constant and wide support base. To evaluate whether loping confers metabolic advantages we monitored ten subjects during loping and running, simulating reduced gravity via partial body suspension, and simulating suited conditions using a lower body exoskeleton. In lunar gravity, loping incurred lower metabolic costs than running for every subject; loping, while efficient at low gravity levels, was less efficient than running in Earth gravity.

ALS metrics are required to meet congressional requirements, but if they are well thought out will help focus technical efforts in appropriate and productive directions. This paper addresses the benefits and limitations of using equivalent system mass as an ALS metric.

In this paper, the claim is that the information available in the passenger vehicle can be viewed as biased towards entertainment as opposed to vehicle handling. To support this claim, I discuss first a simplified description of driving behavior: street driving can be thought of as a highly complex task comprising two principal aspects: vehicle control (VC) and everything else (EE). I then propose ways to adjust the information bias of the vehicle in favor of VC and discuss concrete examples of work: vehicle control gauges, rear speed display and the ESX-2 Concept Car. However, my view is that the information bias problem is not so much a "technology" problem as it is a "knowledge" problem. The vehicle control aspect of street driving appears inadequately respected and, consequently, inadequately articulated.

Through the use of an “Integrated Product Team” approach and new inspection techniques incorporating the latest in imaging capabilities and automation, the costs of some man-power intensive tasks can now be drastically reduced. Also, through the use of advanced eddy current techniques, the detectable size of cracks under flush-head fasteners can be reduced while maintaining reliable inspection. This article describes the evaluation and results obtained using eddy current technology to determine the minimum fasteners, Secondly, it describes the integrated efforts of engineers at Boeing DPD and Northwest Airlines in the successful application of MAUS eddy current scanning of the DC-10 circumferential and axial crow splices. The eddy current scanning greatly reduced the man-hour effort required for the existing radiographic inspection

Advancements in electrical, mechanical, and structural design onboard modern more electric aircraft have added significant stress to the thermal management systems (TMS). A thermal management system level analysis tool has been created in MATLAB/Simulink to facilitate rapid system analysis and optimization to meet the growing demands of modern aircraft. It is anticipated that the tracking of thermal energy through numerical integration will lead to more accurate predictions of worst case TMS sizing conditions. In addition, the non-proprietary nature of the tool affords users the ability to modify component models and integrate advanced conceptual designs that can be evaluated over multiple missions to determine the impact at a system level.

The new combinations such as composites and titanium that are being used on today's new airplanes are proving to be very challenging when drilling holes during manufacturing and assembly operations. Gone are the days of hand drilling with high speed steel drills through soft aluminum structure, after which aluminum rivets would be swaged into those holes with very generous tolerances. The drilling processes today need to use cutter materials hard enough and tough enough to cut through hard metals such as titanium, yet be sharp enough to resistant abrasion and maintain size when drilling through composites. There is a constant search for better cutters and drills that can drill a greater number of holes. The cost of materials used in today's aircraft is much higher. The cutting tools are more expensive and the hole tolerances are much tighter.