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The International Space Station (ISS) United States Operational Segment (USOS) received the first two permanent ISS Crew Quarters (CQ) on Utility Logistics Flight Two (ULF2) in November 2008. As many as four CQs can be installed in the Node 2 element to increase the ISS crew member size to six. The CQs provide crew members with private space that has enhanced acoustic noise mitigation, integrated radiation-reduction material, communication equipment, redundant electrical systems, and redundant caution and warning systems. The rack-sized CQ system has multiple crew member restraints, adjustable lighting, controllable ventilation, and interfaces that allow each crew member to personalize his or her CQ workspace. The deployment and initial operational checkout during integration of the ISS CQ to Node 2 is described in this paper.

The effectiveness of serial link articulated robots in aerospace drilling and fastening is largely limited by positional accuracy. Unguided production robotic systems are practically limited to +/-0.5mm, whereas the majority of aerospace applications call for tolerances in the +/-0.25mm range. The precision with which holes are placed on an aircraft structure is affected by two main criteria; the volumetric accuracy of the positioner, and how the system is affected when an external load is applied. Production use and testing of off-the-shelf robots has highlighted the major contributor to reduced stiffness and accuracy as being error ahead of the joint position feedback such as backlash and belt stretch. These factors affect the omni-directional repeatability, thus limiting accuracy, and also contribute to deflection of the tool point when process forces are applied.

The paper explains the compact fixturing based on magneto-rheological (MR) fluids that have been designed and validated for aeronautic stringers milling. The MR fluid based tooling developed is flexible and reconfigurable as it can be adapted to different profile's lengths and sections and it is able to fix compliant workpieces without reference faces as the MR fluid adapts to the outer shape of each profile. The MR fluid based tooling is suitable to hold non-magnetic materials such as aluminum and also materials that do not admit high clamping forces, such as titanium, because they will appear as deformation after machining due to the memory effect of titanium. The MR fluid based tooling has been tested in a machine environment under real machining conditions and promising results have been obtained.

This paper describes the principles of a new method to compensate for tool wear when drilling in complex materials such as Carbon Fibre Reinforced Plastics (CFRP), Carbon Fibre Reinforced Plastics / Titanium (CFRP/Ti) and Carbon Fibre Reinforced Plastics / Alloy (CFRP/AI) stacks. A reliable and repeatable hole quality is essential, especially in automatic drilling applications with robots or gantries. The method combines the unique feature to dynamically adjust the drilling diameter in very small steps in an Orbital drilling End-effector and a new type of software algorithm to predict and compensate for the tool wear in different materials. With this method a large number of holes can be drilled without changing the cutting tool, and a Cpk value of more than 2,5 can be achieved.

This article begins by describing the need for a new method and tool for performing a sustainability assessment for manufacturing processes and systems. A brief literature survey is done to highlight the major existing methods and tools, their function, and their shortcomings. The article goes on to describe the general approach of the method before describing a computer aided tool that has been developed to implement the method. The article concludes with a walk through of a generic use case that describes where such a method would be useful and how such a tool would be implemented.

The commercial turbofan trend of increasing bypass ratio and decreasing fan pressure ratio has seen its latest market entry in Pratt & Whitney's PurePower™ product line, which will power regional aircraft for the Bombardier and Mitsubishi corporations, starting in 2013. The high-bypass-ratio, low-fan-pressure-ratio trend, which is aimed at diminishing noise while increasing propulsive efficiency, combines with contemporary business factors including the escalating cost of testing and limited availability of simulated altitude test sites to pose formidable challenges for engine certification and performance validation. Most fundamentally, high bypass ratio and low fan pressure ratio drive increased gross-to-net thrust ratio and decreased fan temperature rise, magnifying by a factor of two or more the sensitivity of in-flight thrust and low spool efficiency to errors of measurement and assumption, i.e., physical modeling.

Several space agencies have announced plans to return humans to the Moon in the near future. The objectives of these missions include using the Moon as a stepping-stone towards crewed missions to Mars, to test advanced technology, and to further exploration of the Moon for scientific research and in-situ resource utilization. To meet these objectives, it will be necessary to establish and operate a lunar base. As a result, a wide variety of tasks that may pose a number of crew health and safety risks will need to be performed on the surface of the Moon. Therefore, to ensure sustainable human presence on the Moon and beyond, it is essential to anticipate potential risks, assess the impact of each risk, and devise mitigation strategies. To address this, a nine-week intensive investigation was performed by an international, interdisciplinary and intercultural team on how to maximize crew safety on the lunar surface through a symbiotic relationship between astronauts and robots.

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.

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.

As aircraft programs currently ramp up, productivity of assembly processes needs to be improved while keeping quality, reliability and manufacturing cost requirements. Efficiency of the drilling process still remains an issue particularly in the case of CFRP/metal stacks: hot and long metallic chips are difficult to remove and often damage the surface of CFRP holes. Low frequency axial vibration drilling has been proposed to solve this issue. This innovative drilling process allows breaking up the metallic chips in such a way that jamming is avoided. This paper presents a case of CFRP/Ti6Al4V drilling on a CNC machine where productivity must be increased. A comparison is made between the current regular process and the MITIS drilling process. First the analysis and comparison method is presented. The current process is analyzed and its limits are highlighted. Then the vibration process is implemented and its performances are studied.

The use of composite materials and composite stackups (CO-Ti or CO-Al) in aerospace and automotive applications has been and will continue to grow at a very high rate due to the high strength and low weight of the materials. One key problem manufacturers have using this material is the ability to efficiently drill holes through the layers to install fasteners and other components. This is especially true in stackups of CFRP and titanium due to the desire of drilling dry for the CFRP layer and the need for cooling when drilling the high strength Ti layer. By using CO2 through tool cooling, it is possible to protect both layers. Through work supported by the National Science Foundation (NSF) and Department of Energy (DOE) it is shown that CO2 through tool cooling productivity can be significantly increased while maintaining required hole tolerances in both the composite and Ti layers. Improvements in tool life have been demonstrated when compared to either emulsion or dry drilling.

The 30 month COMET project aims to overcome the challenges facing European manufacturing industries by developing innovative machining systems that are flexible, reliable and predictable with an average of 30% cost efficiency savings in comparison to machine tools. From a conceptual point of view, industrial robot technology could provide an excellent base for machining being both flexible and cost efficient. However, industrial robots lack absolute positioning accuracy, are unable to reject disturbances in terms of process forces and lack reliable programming and simulation tools to ensure right first time machining, once production commences. These three critical limitations currently prevent the use of robots in typical machining applications. The COMET project is co-funded by the European Commission as part of the European Economic Recovery Plan (EERP) adopted in 2008.

The 30 month COMET project aims to overcome the challenges facing European manufacturing industries by developing innovative machining systems that are flexible, reliable and predictable with an average of 30% cost efficiency savings in comparison to machine tools. From a conceptual point of view, industrial robot technology could provide an excellent base for machining being both flexible and cost efficient. However, industrial robots lack absolute positioning accuracy, are unable to reject disturbances in terms of process forces and lack reliable programming and simulation tools to ensure right first time machining, once production commences. These three critical limitations currently prevent the use of robots in typical machining applications. The COMET project is co-funded by the European Commission as part of the European Economic Recovery Plan (EERP) adopted in 2008.

The demand of fulfilling increasing Prime Customer requirements forces Tier 1 suppliers to continually improve their system solutions. Typically, this will involve integration of “state of the art” tools to afford the Tier 1 supplier a throughput and cost advantage. The subject “Production Optimization Approach” addresses the machine and process optimization of automated fastening machines in operation at customer factories. The paper will describe and focus on the main aspects of production optimization of existing machines to meet and exceed the required customer production and reporting criteria. Furthermore, the paper will present existing examples based on use of the established diagnostic tools

The beneficial effects of contact disruption in modulation-assisted machining of aerospace alloys have been well documented, but sources for such improvements are not well understood. This study explores the underlying nature of differences that occur in energy dissipation during conventional and modulation-assisted machining by characterizing the relationship between controllable process parameters and their effects on chip formation. Simultaneous in situ force and tool position measurements are used to show that the forces in modulation-assisted machining can be described by empirical force models in conventional machining conditions. These models are found to accurately describe plastic dissipation over a range of modulation conditions and configurations, including in cases where energy expenditure decreases with the application of modulation. These observations suggest that the underlying response in modulation-assisted machining is analogous to that of conventional machining.

The term “productivity” all too often has becomes a buzz-word, ultimately diminishing its perceived importance. However, productivity is the major concern of any team, and therefore must be defined to gain an appropriate understanding of how a system is actually working. Here, productivity means the level of contribution to the throughput of a system such as defined in the Theory of Constraints. In the field of space exploration, the throughput is the number of milestones of the mission accomplished as well as the potential survival during extreme events (due to failures or other unplanned events). For a time tasks were accomplished by expert individuals (e.g., an astronaut), but recently team structures have become the norm. It is clear that with increased mission complexity, “no single entity can have complete knowledge of or the abilities to handle all matters” [10].

Several new technologies are now emerging to improve adhesive supply and formulation along with surface treatments that have the potential to offer significant improvements to both surface energy and cleanliness [3]. Additionally, the miniaturisation of laboratory techniques into portable equipment offers potential for online surface energy and chemical analysis measurement for use as quality control measures in a production environment. An overview of newly available technology is given here with several devices studied in further detail. Technologies assessed further in this paper are; portable surface contact angle measurement, ambient pressure plasma cleaning, portable FTIR measurement and adhesive mixing equipment. A number of potential applications are outlined for each device based on the operational technique. The practical aspects of implementation and the perceived technology readiness levels for operation, implementation and results are also given.

1 The current pressure across the entire aerospace industry to reduce operating costs and increase efficiency has arguably never been greater. Thus the need to improve parameters such as availability and reliability, and increase the tools and services associated with more efficient aircraft operations and sustainment is now paramount. Moreover, these improvements are seen by many as important factors that define the differentiation and competitiveness of not only current but also future aircraft fleets. The paper will focus on some of the opportunities for OEMs that arise from implementing Integrated Vehicle Health Management (IVHM) systems on their platforms and the challenges associated with evaluating the costs and benefits of their implementation and operation.

Electroimpact's newest riveting machine features a track-style injector with Bomb Bay Ejection Doors. The Bomb Bay Ejection Doors are a robust way to eject fasteners from track style injector. Track style injectors are commonly used by Electroimpact and others in the industry. Using the Bomb Bay Doors for fastener ejection consists of opening the tracks allowing very solid clearing of an injector when ejecting a fastener translating to a more reliable fastener delivery system. Examples of when fastener ejection is needed are when a fastener is sent backwards, when there are two in the tube, or when a machine operator stops or resets the machine during a fastening cycle. This method allows fasteners to be cleared in nearly every situation when ejecting a fastener is required. Additional feature of Electroimpact's new injection system is integrated anvil tool change.

Metal matrix composites (MMCs) exhibit superior characteristics such as low weight, high stiffness, and high mechanical and physical properties. Inheriting such an outstanding combination of specifications, they are nowadays considered as the promising materials in the aerospace and biomedical industries. However, the presence of high abrasive reinforcing particles in MMCs leads to severe manufacturing issues. Due to the tool-particle interactions which occur during the machining of MMCs, high tool wear and poor surface finish are induced and those elements are considered as the main drawbacks of cutting MMCs. In this study, dry turning experiments were conducted for two different inserts and coated carbide on a bar of titanium metal matrix composite (Ti-MMC). Semi-finishing machining is operated with cutting parameters based on the tool supplier's recommendations which were not fully optimized. The maximum flank wear length (VBBmax) was selected as the tool wear criteria.