Adapting advanced engineering design approaches to building design - potential benefits

A number of industries continuously progress advancing their design approaches based on the changing market constraints. Examples such as car, ship and airplane manufacturing industries utilize process setups and techniques, that differ significantly from the processes and techniques used by the traditional building industry. One important difference between the building and other industries is that no prototypes are trialed and tested before manufacturing. This fact causes the design stages to be highly iterative without implementing prototype performance data into the global design process. Evolutionary design i.e. is one technique that aims to adapt the biologic process of evolution to engineering. This technique could have the potential benefit of reducing the design iteration from concept creation to construction. The paper identifies possible differences between the industries and the analysis of the benefits from adapting Evolutionary design to concept creation, evaluation and optimization based on building performance criteria. This paper summarizes the latest research findings documented in subject related literature. Furthermore the iterative character of building design will be detailed by stating key results from design team observations. The final conclusions will indicate reasons why techniques as evolutionary design were not yet successfully integrated to building design

APPLICATION OF SUBSYSTEMS CHANGE RANKING METHODOLOGY IN AIRCRAFT REDESIGN PROCESS

Redesigning an aircraft is hardly a straightforward task. Due to its high susceptibility to change effects propagation, it becomes very important to select the right initiating change components to minimize redesign development risks. With realization that there are often several different ways to redesign an existing aircraft for satisfying similar requirements, designers might require assistance in selecting suitable initiating change components in their redesign plan. A methodology that systematically ranks the subsystems of the chosen baseline design according to their estimated redesign risk is proposed here. It is strongly believed that making this information available to designers during the early redesign stages will help them to make a better redesign plan. KEY WORDS: subsystems ranking, aircraft redesign, redesign plan ABSTRAK: Reka semula sesebuah pesawat udara bukanlah satu tugas yang jelas dan mudah. Memandangkan ia mudah rentan terhadap perubahan rambatan, amatlah penting untuk memilih penukaran komponen yang sesuai pada peringkat awal untuk mengurangkan masalah pembangunan reka semula. Menyedari bahawa terdapat beberapa cara untuk mereka semula pesawat udara yang sedia ada, demi memperolehi keputusan keperluan yang serupa dan memberansangkan, pereka wajar mendapatkan bantuan dari segi penukaran komponen yang sesuai pada peringkat awal pembangunan reka semula yang menepati rangka pelan reka bentuk mereka. Metodologi yang sistematik meletakkan subsistem dasar reka bentuk yang dipilih, berdasarkan anggaran risiko reka bentuk semula dicadangkan di dalam kertas kerja ini. Adalah diyakini bahawa dengan memperolehi informasi ini di peringkat permulaan reka bentuk, ia dapat menolong pereka merangka pelan reka cipta yang lebih baik

3D modeling and initial structural analysis of a light aircraft

In a country where aviation is seen as a problem and not a solution, few are the lucky and brave to be part of this wonderful sector. Among these few, thereare people like Marc Kuster who go beyond the simple fact of fly, and take their hobby to the point of designing and building aircraft.This thesis is part of the personal project of Marc Kuster, who more than 20 years ago designed a three-surface airplane with the intention that one day it would become a reality.The ODYSSEUS II, is the product of that design, and in this thesis parts of the airplane design and analysis process are shown. In particular, the thesis is based on the development of the different CAD models and later some first studies are made on the structural, aerodynamic and performance behaviourof the airplane

User driven modelling: Visualisation and systematic interaction for end-user programming with tree-based structures

This thesis addresses certain problems encountered by teams of engineers when modelling complex structures and processes subject to cost and other resource constraints. The cost of a structure or process may be ‘read off’ its specifying model, but the language in which the model is expressed (e.g. CAD) and the language in which resources may be modelled (e.g. spreadsheets) are not naturally compatible. This thesis demonstrates that a number of intermediate steps may be introduced which enable both meaningful translation from one conceptual view to another as well as meaningful collaboration between team members. The work adopts a diagrammatic modelling approach as a natural one in an engineering context when seeking to establish a shared understanding of problems.Thus, the research question to be answered in this thesis is: ‘To what extent is it possible to improve user-driven software development through interaction with diagrams and without requiring users to learn particular computer languages?’ The goal of the research is to improve collaborative software development through interaction with diagrams, thereby minimising the need for end-users to code directly. To achieve this aim a combination of the paradigms of End-User Programming, Process and Product Modelling and Decision Support, and Semantic Web are exploited and a methodology of User Driven Modelling and Programming (UDM/P) is developed, implemented, and tested as a means of demonstrating the efficacy of diagrammatic modelling.In greater detail, the research seeks to show that diagrammatic modelling eases problems of maintenance, extensibility, ease of use, and sharing of information. The methodology presented here to achieve this involves a three step translation from a visualised ontology, through a modelling tool, to output to interactive visualisations. An analysis of users groups them into categories of system creator, model builder, and model user. This categorisation corresponds well with the three-step translation process where users develop the ontology, modelling tool, and visualisations for their problem.This research establishes and exemplifies a novel paradigm of collaborative end-user programming by domain experts. The end-user programmers can use a visual interface where the visualisation of the software exactly matches the structure of the software itself, making translation between user and computer, and vice versa, much more direct and practical. The visualisation is based on an ontology that provides a representation of the software as a tree. The solution is based on translation from a source tree to a result tree, and visualisation of both. The result tree shows a structured representation of the model with a full visualisation of all parts that leads to the computed result.In conclusion, it is claimed that this direct representation of the structure enables an understanding of the program as an ontology and model that is then visualised, resulting in a more transparent shared understanding by all users. It is further argued that our diagrammatic modelling paradigm consequently eases problems of maintenance, extensibility, ease of use, and sharing of information. This method is applicable to any problem that lends itself to representation as a tree. This is considered a limitation of the method to be addressed in a future project

A strategic planning methodology for aircraft redesign

Due to a progressive market shift to a customer-driven environment, the influence of engineering changes on the product's market success is becoming more prominent. This situation affects many long lead-time product industries including aircraft manufacturing. Derivative development has been the key strategy for many aircraft manufacturers to survive the competitive market and this trend is expected to continue in the future. Within this environment of design adaptation and variation, the main market advantages are often gained by the fastest aircraft manufacturers to develop and produce their range of market offerings without any costly mistakes. This realization creates an emphasis on the efficiency of the redesign process, particularly on the handling of engineering changes. However, most activities involved in the redesign process are supported either inefficiently or not at all by the current design methods and tools, primarily because they have been mostly developed to improve original product development. In view of this, the main goal of this research is to propose an aircraft redesign methodology that will act as a decision-making aid for aircraft designers in the change implementation planning of derivative developments. The proposed method, known as Strategic Planning of Engineering Changes (SPEC), combines the key elements of the product redesign planning and change management processes. Its application is aimed at reducing the redesign risks of derivative aircraft development, improving the detection of possible change effects propagation, increasing the efficiency of the change implementation planning and also reducing the costs and the time delays due to the redesign process. To address these challenges, four research areas have been identified: baseline assessment, change propagation prediction, change impact analysis and change implementation planning. Based on the established requirements for the redesign planning process, several methods and tools that are identified within these research areas have been abstracted and adapted into the proposed SPEC method to meet the research goals. The proposed SPEC method is shown to be promising in improving the overall efficiency of the derivative aircraft planning process through two notional aircraft system redesign case studies that are presented in this study.Ph.D.Committee Chair: Prof. Dimitri Mavris; Committee Member: Dr. Elena Garcia; Committee Member: Dr. Neil Weston; Committee Member: Mathias Emeneth; Committee Member: Prof. Daniel P. Schrag

The Effect of Surface Materials and Morphology on Wingsuit Aerodynamics

This study examines the aerodynamic effects of the materials, textiles, and morphologies currently used in wingsuit design and construction. The experiment was a low-speed wind tunnel investigation using a rigid wing with an aspect ratio of 2, a NACA 4418 airfoil cross section and a smooth, polished painted surface as a baseline. The baseline wing was modified by covering the upper and lower surfaces with various textiles currently used in wingsuit construction. This study is the first step in continued research to design and build a wingsuit with superior glide performance compared to current designs. Surface textures and features on the lifting surfaces of wings are known to have significant aerodynamic consequences. This experiment compared the lift and drag of a representative low aspect ratio wing before and after covering the wing with the various fabrics and textiles used in current wingsuit design and arranged the various textiles and other wingsuit features, like zippers and seams, in morphologies currently used in wingsuit construction. The data collected clearly shows current wingsuit materials and morphologies have a potentially large, usually undesirable effect on flight performance. All woven fabrics reduced aerodynamic efficiency as measured by CL/CD. Those treatments with the roughest surfaces greatly reduced lift and increased drag as much as 50% or more and reduced aerodynamic efficiency as much as 75%. Placement of zippers and seams are shown to be critical factors for both aerodynamic efficiency and stability. Current combinations of fabrics and morphologies were shown to be often mutually and additively detrimental to aerodynamic performance. Certain textiles showed possible utility in drag reduction. It was initially thought that the effects of the surface treatments on lift would be the major factor in wingsuit performance. While the effects on lift were significant, the large drag penalties due to woven and textured fabrics and textiles and the early separation of airflow at low angles of attack, appear to have had the greatest effect on the aerodynamic efficiency of a lifting surface with an airfoil cross section

User driven modelling : visualisation and systematic interaction for end-user programming with tree-based structures

This thesis addresses certain problems encountered by teams of engineers when modelling complex structures and processes subject to cost and other resource constraints. The cost of a structure or process may be ‘read off’ its specifying model, but the language in which the model is expressed (e.g. CAD) and the language in which resources may be modelled (e.g. spreadsheets) are not naturally compatible. This thesis demonstrates that a number of intermediate steps may be introduced which enable both meaningful translation from one conceptual view to another as well as meaningful collaboration between team members. The work adopts a diagrammatic modelling approach as a natural one in an engineering context when seeking to establish a shared understanding of problems. Thus, the research question to be answered in this thesis is: ‘To what extent is it possible to improve user-driven software development through interaction with diagrams and without requiring users to learn particular computer languages?’ The goal of the research is to improve collaborative software development through interaction with diagrams, thereby minimising the need for end-users to code directly. To achieve this aim a combination of the paradigms of End-User Programming, Process and Product Modelling and Decision Support, and Semantic Web are exploited and a methodology of User Driven Modelling and Programming (UDM/P) is developed, implemented, and tested as a means of demonstrating the efficacy of diagrammatic modelling. In greater detail, the research seeks to show that diagrammatic modelling eases problems of maintenance, extensibility, ease of use, and sharing of information. The methodology presented here to achieve this involves a three step translation from a visualised ontology, through a modelling tool, to output to interactive visualisations. An analysis of users groups them into categories of system creator, model builder, and model user. This categorisation corresponds well with the three-step translation process where users develop the ontology, modelling tool, and visualisations for their problem. This research establishes and exemplifies a novel paradigm of collaborative end-user programming by domain experts. The end-user programmers can use a visual interface where the visualisation of the software exactly matches the structure of the software itself, making translation between user and computer, and vice versa, much more direct and practical. The visualisation is based on an ontology that provides a representation of the software as a tree. The solution is based on translation from a source tree to a result tree, and visualisation of both. The result tree shows a structured representation of the model with a full visualisation of all parts that leads to the computed result. In conclusion, it is claimed that this direct representation of the structure enables an understanding of the program as an ontology and model that is then visualised, resulting in a more transparent shared understanding by all users. It is further argued that our diagrammatic modelling paradigm consequently eases problems of maintenance, extensibility, ease of use, and sharing of information. This method is applicable to any problem that lends itself to representation as a tree. This is considered a limitation of the method to be addressed in a future project.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Improving the Aircraft Design Process Using Web-Based Modeling and Simulation

Designing and developing new aircraft systems is time-consuming and expensive. Computational simulation is a promising means for reducing design cycle times, but requires a flexible software environment capable of integrating advanced multidisciplinary and multifidelity analysis methods, dynamically managing data across heterogeneous computing platforms, and distributing computationally complex tasks. Web-based simulation, with its emphasis on collaborative composition of simulation models, distributed heterogeneous execution, and dynamic multimedia documentation, has the potential to meet these requirements. This paper outlines the current aircraft design process, highlighting its problems and complexities, and presents our vision of an aircraft design process using Web-based modeling and simulation

Improving the Aircraft Design Process Using Web-based Modeling and Simulation

Designing and developing new aircraft systems is time-consuming and expensive. Computational simulation is a promising means for reducing design cycle times, but requires a flexible software environment capable of integrating advanced multidisciplinary and muitifidelity analysis methods, dynamically managing data across heterogeneous computing platforms, and distributing computationally complex tasks. Web-based simulation, with its emphasis on collaborative composition of simulation models, distributed heterogeneous execution, and dynamic multimedia documentation, has the potential to meet these requirements. This paper outlines the current aircraft design process, highlighting its problems and complexities, and presents our vision of an aircraft design process using Web-based modeling and simulation