1,721,076 research outputs found
Planning in the dark: why major engineering projects fail to achieve key goals
No full textThe arguments, analysis and observations in this paper are based on 10 years of research with partners in the European and US aerospace and defence industries. During this period the authors were part of a team of researchers at Bristol UWE, Southampton University and Rolls-Royce PLC, who were seeking to develop a new methodology and tool set for project management, particularly aimed at large aerospace projects.The research was motivated by the seemingly ubiquitous reality of project failure, with large engineering projects apparently always late and over budget. Here we focus on aerospace and defence, but the problems are generic across all branches of engineering. In our view aerospace and defence have more excuses than most, because not only are the projects huge, they are also globally distributed and highly complex.As our work progressed a fundamental conundrum emerged. As we talked to project managers and assessed the teams that were undertaking the projects it became obvious that they were well educated, intelligent, highly motivated and very capable people. So why were so many projects going wrong? Soon we could see that projects were going wrong in all sectors and in many different countries. So obviously the problems were not to do with incompetence, as they clearly were so generic. Our ultimate finding has been that the very technology available for managing projects today is inadequate. As we argue below, modern, complex projects cannot be planned and executed using 50-year-old project management tools. The paper tells the story of what’s wrong with the current technology and how and why it needs to change. The authors are well aware that there are also cultural problems in project management, but in fact many of these derive from the use of inadequate tools.Many of the insights and arguments developed here have come from discussions with personnel at BAE SYSTEMS, Boeing, Airbus and Rolls-Royce. However, all the cited factual material in this paper comes only from publicly, published sources. We wish to thank all our interviewees, who naturally requested that they remain anonymou
Civilian drones
No full textFor decades, unpersoned planes have been used by the military in places such as Afghanistan and Pakistan to watch the ground and deliver weapons controlled by remote pilots thousands of kilometres away. But now companies and experts are putting their minds to turning military drones into civilian vehicles that can do things cheaper and better than piloted planes. Peter Day investigates unmanned aerial vehicles and how they are already being used by farmers and the police. Also, could a drone be delivering your pizza in the not too distant future
Value driven conceptual design of Unmanned Air System for defence applications
No full textThe work presented concerns the development of a value driven conceptual design assessment framework for a small Unmanned Air System (UAS) to be utilized in a defence application. In the field of Multi-Disciplinary Design Optimization, most recent systematic search has been devoted to fixed topology parametric geometries, pertaining to a single concept, with very little stress put on the optimization of variable topologies describing alternative design concepts. The search is conducted in a highly novel manner, generating a broad range of combinations of UAS configurations and geometries by systematically searching alternative concepts and design configurations through the parameterization of the aircraft geometric topologies. Moreover, the “value” of proposed solutions is assessed in an objective way both from performance and economic perspectives, while the optimal solution is identified after relaxing all of the design constraints as advocated by value driven design philosophy. During the multi-criteria decision analysis, the quantification/conversion of the linguistic preferences of the user between the various attributes to numerical values has disclosed some deficiencies introduced by the unjustifiable numerical scales used in the Analytic Hierarchy Process (AHP). This problem is resolved by a novel value model synthesizing the AHP assessment methodologies with multi-attribute value-focused analysis
Strategic jet engine System design in light of uncertain fuel and carbon prices
No full textSince the Wright brothers took to the skies over 100 years ago, aviation has been powered by fossil fuels. This dependency will not be markedly reduced within the next two decades despite higher and more erratic fuel prices that result from increasingly restricted access to crude oil. Climate change will also force regulators to increase the price of CO2 emissions so that there is an even greater incentive to operate fuel efficient aircraft. This project therefore aims to investigate how the profit generated by a short-range jet engine can be made robust to uncertain fuel and carbon prices in 2030 by applying the Surplus Value Methodology in conjunction with Robust Design techniques
Evaluating design decisions in real-time using operations modelling
No full textContemporary design processes of large aerospace products are rigidly focused on customer specifications in order to meet their expectations. Life cycle costs, design space exploration and value engineering are neglected, often leading to substantial cost overruns and delivery delays. Moreover, customer specifications are not scrutinized and design decisions are made ignoring potential operational knowledge. Value-driven design suggests a new approach using flexible customer specifications in order to find optimal designs by exploring the solution space. One aspect of this optimization is the simulation of the anticipated operational life of a product in order to gain operational knowledge and analyse customer specifications. This paper suggests that an operational simulation can be used actively or reactively by designers during the design process to improve a product. It is investigated how an operational simulation can act as a design decision support tool and how it can react to customer specifications. Answers are presented by means of a simulation model recreating the operational life of a Search-and-Rescue Unmanned Air Vehicle developed in parallel at the University of Southampton. The simulation's ability for acting as a decision support tool is explored by conducting a fuel tank size optimization. Reactive capabilities are explored by calculating the surplus value of using UAVs. This exemplifies the derivation of product specifications as the simulation reveals the value and hence usefulness of given customer specifications. It is shown that operational simulations benefit designers and overall product value by analysing product specifications and guiding designers to more informed design decision
Value driven conceptual design of unmanned air system for a defence application
No full textThe work presented culminates in the development of a value driven conceptual design assessment framework for a small Unmanned Air System (UAS) to be utilized in a defence application. In the field of Multi-Disciplinary Design Optimisation, most recent systematic search has been devoted to fixed topology parametric geometries, pertaining to a single concept, with very little stress put on the optimization of variable topologies describing alternative design concepts. The search is conducted in a highly novel manner, generating a broad range of combinations of UAS configurations and geometries by systematically searching alternative concepts and design configurations through the parameterization of the aircraft geometric topologies. Moreover, the “value” of proposed solutions is assessed in an objective way both from performance and economic perspectives, while the optimal solution is identified based on the user’s needs after relaxing all of the design constraints. During the multi-criteria decision analysis, the quantification/conversion of the linguistic preferences of the user between the various attributes to numerical values has disclosed some deficiencies introduced by the unjustifiable numerical scales used in the Analytic Hierarchy Process (AHP) and a novel value model for consistent value assessment is introduced, synthesizing the AHP assessment methodologies with multi-attribute value-focused analysis
From radiosonde to papersonde: the use of conductive inkjet printing in the massive atmospheric volume instrumentation system (MAVIS) project
No full textA promising method for the collection of atmospheric data is the en masse release of ‘flocks’ of nano Unmanned Aerial Vehicles (UAVs) from meteorological balloons. These UAVs would need to be lightweight, cheap, and disposable. Recent advances in Conductive Inkjet Printing (CIP) have allowed the fabrication of electronic circuits onto thin substrates, such as paper. We demonstrate that the direct printing of circuit tracks onto photo paper will allow the creation of such aircraft, which are not only disposable, but biodegradable. We present a prototype ‘Papersonde’, which features a directly printed circuit with a microprocessor, transceiver, barometer and temperature sensor. We also describe in detail the fabrication steps required to create the Papersonde. It is hoped that this circuit will form the basis of the nano UAVs we create for the Massive Atmospheric Volume Instrumentation System (MAVIS) project
A generic operational simulation for early design civil unmanned aerial vehicles
No full textContemporary aerospace programmes often suffer from large cost overruns, delivery delays and inferior product quality. This is caused in part by poor predictive quality of the early design phase processes with regards to the operational environment of a product. This paper develops the idea of a generic operational simulation that can help designers to rigorously analyse and test their early product concepts. The simulation focusses on civil Unmanned Air Vehicle products and missions to keep the scope of work tractable. The research agenda is introduced along with ideas, initial results and future work. Designers specify details about their product, its environment and anticipated operational procedures. The simulation returns information that can help to estimate the value of the product using the value-driven design approach. Information will include recurring and non-recurring mission cost items. The research aim is to show that an operational simulation can improve early design concepts, thereby reducing delays and cost overruns. Moreover, a trade-off between mission fidelity and model generality is sought along with a generic ontology of civil Unmanned Air Vehicle missions and guidelines about capturing operational informatio
Visualisation of cost information
No full textIn this paper, a prototype package developed within the scope of the Implied Cost Evaluation System (ICES) project at the University of the West of England will be presented. It offers visualization and analysis features for engineering cost data. These tools permit the cost engineer to browse and locate stages in the manufacturing process where requirements, such as time and cost to manufacture, are not met. Once a problematic entity has been identified, the product or parts of it should be redesigned. Any inappropriate manufacturing processes should be either improved or substituted for a more suitable one. Ease of use and efficient information delivery have been particularly emphasized
Generalising optimal mean setting for any number and combination of serial and parallel manufacturing operations
No full textConsider a production system where products are continuously manufactured and their features inspected for conformance within specification limits. If features are produced above or below the specification limits, they are either subject to rework or the product scrapped. Optimal mean setting may be applied to adjust the manufacturing means to influence the amount of rework or scrap produced, maximising profit. Within the production system, manufacturing and then inspecting each feature in turn is termed serial production, whereas manufacturing multiple features before inspection is termed parallel production. This paper develops a generalised expression to optimise the mean values of each feature (optimal mean setting), where n number of features are produced in any combination of serial and parallel operations. Previous literature is restricted to considering two features in parallel. The production of multiple features in combinations of serial and parallel operations is not fully considered. The new generalised expression is validated by showing it is consistent with specific cases from past literature. The approach is then applied to a practical example of a gearbox shaft, considering the expected profit of eight possible manufacturing sequences, as well as the deviation of the manufactured means relative to the design intent. The generalised expression is widely applicable in component design and manufacturing planning where the process capability index (Cpk) of features is below one. The generalised expression also forms the basis for trade-offs between profitability and minimising deviations of manufactured means, which is the subject of further development
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