Responsive fixture design using dynamic product inspection and monitoring technologies for the precision machining of large-scale aerospace parts

When machining a large-scale aerospace part, the part is normally located and clamped firmly until a set of features are machined. When the part is released, its size and shape may deform beyond the tolerance limits due to stress release. This paper presents the design of a new fixing method and flexible fixtures that would automatically respond to workpiece deformation during machining. Deformation is inspected and monitored on-line, and part location and orientation can be adjusted timely to ensure follow-up operations are carried out under low stress and with respect to the related datum defined in the design models.

Metrology enhanced tooling for aerospace (META):strategies for improved accuracy of jig built structures

The accuracy of many aerospace structures is limited by the accuracy of assembly tooling which is in turn limited by the accuracy of the measurements used to set the tooling. Further loss of accuracy results from different rates of thermal expansion for the components and tooling. This paper describes improved tooling designs and setting processes which have the potential to significantly improve the accuracy of aerospace structures. The most advanced solution described is environmentally isolated interferometer networks embedded within tooling combined with active compensation of component pick-ups. This would eliminate environmental effects on measurements while also allowing compensation for thermal expansion. A more immediately realizable solution is the adjustment of component pick-ups using micrometer jacking screws allowing multilateration to be employed during the final stages of the setting process to generate the required offsets. Copyright © 2011 SAE International.

Revisiting the lean agile paradigm:an empirical study in the aerospace industry

Much has been written about the potential impact of Lean Agile paradigm on firm's supply chain performance. However, most of the existing studies mainly pointed out Lean is for cost reduction, whereas Agility is for attaining flexibility. There are little empirical studies in literature that examined how Lean Agile paradigm impacts on supply chain performance. This paper aims to address this gap by studying the influence of Lean and Agility paradigms on a single commodity supply chain delivery performance in the aerospace industry. Data was collected from four separate 'Rigid pipes' supply chains to study how manufacturing alignment impacts on the delivery performance. Implications of the study to practitioners and academia are discussed and future research outlined.

Tubular and sector heat pipes with interconnected branches for gas turbine and/or compressor cooling

Designing turbines for either aerospace or power production is a daunting task for any heat transfer scientist or engineer. Turbine designers are continuously pursuing better ways to convert the stored chemical energy in the fuel into useful work with maximum efficiency. Based on thermodynamic principles, one way to improve thermal efficiency is to increase the turbine inlet pressure and temperature. Generally, the inlet temperature may exceed the capabilities of standard materials for safe and long-life operation of the turbine. Next generation propulsion systems, whether for new supersonic transport or for improving existing aviation transport, will require more aggressive cooling system for many hot-gas-path components of the turbine. Heat pipe technology offers a possible cooling technique for the structures exposed to the high heat fluxes. Hence, the objective of this dissertation is to develop new radially rotating heat pipe systems that integrate multiple rotating miniature heat pipes with a common reservoir for a more effective and practical solution to turbine or compressor cooling. In this dissertation, two radially rotating miniature heat pipes and two sector heat pipes are analyzed and studied by utilizing suitable fluid flow and heat transfer modeling along with experimental tests. Analytical solutions for the film thickness and the lengthwise vapor temperature distribution for a single heat pipe are derived. Experimental tests on single radially rotating miniature heat pipes and sector heat pipes are undertaken with different important parameters and the manner in which these parameters affect heat pipe operation. Analytical and experimental studies have proven that the radially rotating miniature heat pipes have an incredibly high effective thermal conductance and an enormous heat transfer capability. Concurrently, the heat pipe has an uncomplicated structure and relatively low manufacturing costs. The heat pipe can also resist strong vibrations and is well suited for a high temperature environment. Hence, the heat pipes with a common reservoir make incorporation of heat pipes into turbo-machinery much more feasible and cost effective.

The Metrology Enhanced Tooling for Aerospace (META) framework

Aerospace manufacturers typically use monolithic steel fixtures to control the form of assemblies. This tooling is very expensive, has long lead times and has little ability to accommodate product variation and design changes. Since the tool setting and recertification process is manual and time consuming, monolithic structures are required in order to maintain the tooling tolerances for multiple years without recertification. This paper introduces the Metrology Enhanced Tooling for Aerospace (META) Framework which interfaces multiple metrology technologies with the tooling, components, workers and automation. This will allow rapid or even real-time fixture re-certification with improved product verification leading to a reduced risk of product non-conformance and increased fixture utilization while facilitating flexible fixtures.

The Philippines in the Aerospace Global Value Chain

This report uses the Duke CGGC Global Value Chain (GVC) framework to examine the role of the Philippines in the global aerospace industry and identify opportunities for the country to upgrade. The Philippines is a newcomer to the growing global aerospace manufacturing industry. Although the country has been host to a major flight controls manufacturer since 1985, the industry really only began to expand within the past five to ten years. During this recent period (2007-2014), the country has rapidly ramped up its aerospace manufacturing exports, reaching US$604 million in 2014 and more than tripling employment. The industry now employs 3,000 full time and 3,000 part time workers. Although still a very small player, accounting for less than 0.15% of the global industry, this incipient growth is promising. Both foreign firms and local suppliers that have established operations in the industry have already achieved some degree of upgrading within a short timeframe. These include expanding the product lines served, obtaining essential process certifications and upgrading beyond basic assembly operations to undertake additional manufacturing processes such as machining as well as initiating procurement and engineering functions in country.

Crowdsourcing User-Contributed Solutions to Aerospace Product Development Issues through Micro-Blogging

Revenue and production output of the United Kingdom’s Aerospace Industry (AI) is growing year on year and the need to develop new products and innovative enhancements to existing ranges is creating a critical need for the increased utilisation and sharing of employee knowledge. The capture of employee knowledge within the UK’s AI is vital if it is to retain its pre-eminent position in the global marketplace. Crowdsourcing, as a collaborative problem solving activity, allows employees to capture explicit knowledge from colleagues and teams and also offers the potential to extract previously unknown tacit knowledge in a less formal virtual environment. By using micro-blogging as a mechanism, a conceptual framework is proposed to illustrate how companies operating in the AI may improve the capture of employee knowledge to address production-related problems through the use of crowdsourcing. Subsequently, the framework has been set against the background of the product development process proposed by Maylor in 1996 and illustrates how micro-blogging may be used to crowdsource ideas and solutions during product development. Initial validation of the proposed framework is reported, using a focus group of 10 key actors from the collaborating organisation, identifying the perceived advantages, disadvantages and concerns of the framework; results indicate that the activity of micro-blogging for crowdsourcing knowledge relating to product development issues would be most beneficial during product conceptualisation due to the requirement for successful innovation.

The Evolution of 'Design Build Fly' Led Teaching in Aerospace Engineering

This paper describes the evolution of a ‘Design - Build-Fly’ (DBF) approach to the delivery and assessment of a Stage Three Aircraft Design module. It focuses on the primary learning outcomes around the design and manufacturing functions associated with the development of a remotely controlled aircraft. The work covers a six year period from 2011 to present mapping the transformation of the module from report based assessment to a more hands on approach resulting in a fully functioning remotely controlled aircraft. Results show that both the staff and student experience improved across key performance metrics including student feedback, learning and competency development. Challenges still remain in methods of placing students within teams and maintaining technical rigour in reporting as students develop vocational skills and more reflective writing styles.

Identifying the Impact of Incomplete Datasets on Process Cycle Time Prediction in an Aerospace Assembly Line

Supply Chain Simulation (SCS) is applied to acquire information to support outsourcing decisions but obtaining enough detail in key parameters can often be a barrier to making well informed decisions.
One aspect of SCS that has been relatively unexplored is the impact of inaccurate data around delays within the SC. The impact of the magnitude and variability of process cycle time on typical performance indicators in a SC context is studied.
System cycle time, WIP levels and throughput are more sensitive to the magnitude of deterministic deviations in process cycle time than variable deviations. Manufacturing costs are not very sensitive to these deviations.
Future opportunities include investigating the impact of process failure or product defects, including logistics and transportation between SC members and using alternative costing methodologies.

Virtual Reality as a tool to Assist Learning in Aerospace Assembly

This study examines whether virtual reality (VR) is more superior to paper-based instructions in increasing the speed at which individuals learn a new assembly task. Specifically, the work seeks to quantify any learning benefits when individuals have been given the opportunity and compares the performance of two groups using virtual and hardcopy media types to pre-learn the task. A build experiment based on multiple builds of an aircraft panel showed that a group of people who pre-learned the assembly task using a VR environment completed their builds faster (average build time 29.5% lower). The VR group also made fewer references to instructional materials (average number of references 38% lower) and made fewer errors than a group using more traditional, hard copy instructions. These outcomes were more pronounced during build one with differences in build time and number of references showing limited statistical differences.

The role of Lean at the interface with between operations management and applied services within a large aerospace organisation: a boundary spanning perspective

Increased complexity in large design and manufacturing organisations requires improvements at the operations management (OM)–applied service (AS) interface areas to improve project effectiveness. The aim of this paper is explore the role of Lean in improving the longitudinal efficiency of the OM–AS interface within a large aerospace organisation using Lean principles and boundary spanning theory. The methodology was an exploratory longitudinal case approach including exploratory interviews (n = 21), focus groups (n = 2), facilitated action-research workshops (n = 2) and two trials or experiments using longitudinal data involving both OM and AS personnel working at the interface. The findings draw upon Lean principles and boundary spanning theory to guide and interpret the findings. It was found that misinterpretation, and forced implementation, of OM-based Lean terminology and practice in the OM–AS interface space led to delays and misplaced resources. Rather both OM and AS staff were challenged to develop a cross boundary understanding of Lean-based boundary (knowledge) objects in interpreting OM requests. The longitudinal findings from the experiments showed that the development of Lean Performance measurements and lean Value Stream constructs was more successful when these Lean constructs were treated as boundary (knowledge) objects requiring transformation over time to orchestrate improved effectiveness and in leading to consistent terminology and understanding between the OM–AS boundary spanning team.

Konzeption, Implementierung und Anwendung eines automatisierten aerothermodynamischen Vorentwurfsprozesses für Axialturbinen

In dieser Arbeit wird ein Prozess für den frühen aerothermodynamischen Entwurf von Axialturbinen konzipiert und durch Kopplung einzelner Computerprogramme im DLR Göttingen realisiert. Speziell für die Erstauslegung von Geometrien und die Vorhersage von globalen Leistungsdaten beliebiger Axialturbinen wurde ein neues Programm erzeugt. Dessen effiziente Anwendung wird mit einer zu diesem Zweck konzipierten grafischen Entwurfsumgebung ausgeführt. Kennzeichnend für den Vorentwurfsprozess in dieser Arbeit ist die Anwendung von ein- und zweidimensionaler Strömungssimulation sowie der hohe Grad an Verknüpfung der verwendeten Programme sowohl auf prozesstechnischer wie auch auf datentechnischer Ebene. Dabei soll dem sehr frühen Entwurf eine deutlich stärkere Rolle zukommen als bisher üblich und im Gegenzug die Entwurfszeit mit höher auflösenden Vorentwurfsprogrammen reduziert werden. Die Anwendung der einzelnen Programme im Rahmen von Subprozessen wird anhand von exemplarischen Turbinenkonfigurationen in der Arbeit ebenso dargestellt, wie die Validierung des gesamten Entwurfsprozesses anhand der Auslegung einer folgend realisierten und erfolgreich operierenden Axialturbine eines Triebwerkssimulators für Flugzeug-Windkanalmodelle (TPS). Neben der Erleichterung von manueller Entwurfstätigkeit durch grafische Benutzerinteraktion kommt in einzelnen Subprozessen eine automatisierte Mehrziel-Optimierung zum Einsatz.