| 1. |
- Amadori, Kristian, 1976-, et al.
(författare)
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Aircraft Conceptual Design Optimization
- 2008
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Ingår i: International Congress of the Aeronautical Sciences ICAS,2008. - Stockholm, Sweden : ICAS.
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Konferensbidrag (refereegranskat)abstract
- Aircraft design is an inherently multidisciplinary activity that requires different models and tools for various aspects of the design. At Linköping University a novel design framework is being developed to support the initial conceptual design phase of new aircraft. By linking together various modules via a userfriendly spreadsheet interface, the framework allows multidisciplinary analysis and optimizations to be carried out. The geometrical model created with a high-end CAD system, contains all the available information on the product and thus it plays a central role in the framework. In this work great attention has been paid to techniques that allow creating robust yet highly flexible CAD models. Two different case studies are presented. The first one is a hypothetic wing-box design that is studied with respect to aerodynamic efficiency and loads, and to structural analysis. In this study two approaches were compared. In one case the wing-box design was optimized with a fixed number of structural elements, where only dimensions and position were allowed to change. Then the same wing-box was analyzed allowing also the number of structural elements to vary. Thus only the parts that are required are left and a more efficient design can be obtained. In the second case study a mission simulation is performed on a UAV-type aircraft. Required data for the simulation are gathered from the CAD model and from aerodynamic analysis carried out with PANAIR, a high order panel code. The obtained data are then used as inputs parameters for flight simulation in order to determined hydraulic systems characteristics.
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| 2. |
- Amadori, Kristian, 1976-
(författare)
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On Aircraft Conceptual Design : A Framework for Knowledge Based Engineering and Design Optimization
- 2008
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis presents a design framework where analytical tools are linked together and operated from an efficient system level interface. The application field is aircraft conceptual design. Particular attention has been paid to CAD system integration and design optimization.Aircraft design is an inherently multidisciplinary process. The goal is to search for the design that, in the best of possible ways, fulfills the requirements. It is therefore desirable to be able to effectively investigate and analyze solutions from a variety of points of view, weighting together the results and gathering a general figure of merit. At the same time, increasing competition on a global market forces to shorten the design process and to reduce costs. Thus a system that allows a tight and efficient integration of different disciplines and improving data flow and storage plays a key role.Integrating a CAD system to the framework is of central relevance. The geometrical model includes most of the information; specific data, required to carry out particular analysis, can be extracted from it. This is possible adopting parametric associative models that are controlled from a spreadsheet user interface. Strategies for building CAD models with a very high degree of flexibility are presented. Not only the external shape can be changed, but also the internal structure can be completely modified. Structural elements can be added or removed, and their position and shaping changed.In this work the design of an Unmanned Aerial Vehicle is used as test case for comparing three different optimization algorithms. The presented framework is also used for automatically design Micro Aerial Vehicles, starting from a short list of requirements and ending with a physical prototype produced by a rapid prototyping machine.
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| 3. |
- Amadori, Kristian, 1976-, et al.
(författare)
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Using CAD-Tools and Aerodynamic Codes in a Distributed Conceptual Design Framework
- 2007
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Ingår i: Aerospace Sciences Meeting and Exhibit,2007. - USA : AIAA.
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Konferensbidrag (refereegranskat)abstract
- Aircraft design is an inherently multi-disciplinary activity that requires different models and tools for various aspects of the design. At Linköping University a novel design framework is being developed to support the initial conceptual design phase of a new aircraft. Different modules are included, each one addressed to analyze and evaluate different aspects of the airplane, such as its aerodynamics, its weight and structure, its sub systems and its performances. All modules are easily accessible from a user-friendly interface based on an Excel spreadsheet. The link between all modules is based on Service Oriented Architecture (SOA) and allows both distribution and integration of all functions. This paper will present the framework, give an overview of its development status and give an indication on the future work.
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| 4. |
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| 5. |
- Knöös Franzén, Ludvig, 1990-, et al.
(författare)
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A Breakdown of System of Systems Needs Using Architecture Frameworks, Ontologies and Description Logic Reasoning
- 2021
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Ingår i: Aerospace. - : MDPI. - 2226-4310. ; 8:4
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Tidskriftsartikel (refereegranskat)abstract
- Aerospace systems are connected with the operational environment and other systems in general. The focus in aerospace product development is consequently shifting from a singular system perspective to a System-of-Systems (SoS) perspective. This increasing complexity gives rise to new levels of uncertainty that must be understood and managed to produce aerospace solutions for an ever-changing future. This paper presents an approach to using architecture frameworks, and ontologies with description logic reasoning capabilities, to break down SoS needs into required capabilities and functions. The intention of this approach is to provide a consistent way of obtaining the functions to be realized in order to meet the overarching capabilities and needs of an SoS. The breakdown with an architecture framework results in an initial design space representation of functions to be performed. The captured knowledge is then represented in an ontology with description logic reasoning capabilities, which provides a more flexible way to expand and process the initial design space representation obtained from the architecture framework. The proposed approach is ultimately tested in a search and rescue case study, partly based on the operations of the Swedish Maritime Administration. The results show that it is possible to break down SoS needs in a consistent way and that ontology with description logic reasoning can be used to process the captured knowledge to both expand and reduce an available design space representation.
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| 6. |
- Knöös Franzén, Ludvig, 1990-, et al.
(författare)
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A System of Systems Approach for Search and Rescue Missions
- 2020
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Konferensbidrag (refereegranskat)abstract
- System-of-Systems Engineering (SoSE) has become a constantly growing field within product development for complex systems. Systems are becoming more and more connected with other systems and the operational environment in general. This takes the development process to new levels of complexity where high degrees of uncertainties are expected due to ever occurring changes in the operational environment, and other external factors such as politics, economy, and technology. This creates a need of being able to understand the influence of changes early in the development process and to facilitate the systems? perseverance. The focus of the development shifts from fulfilling specific requirements, to being able to meet needs and deliver capabilities over time. Additionally, modeling and simulation for complex systems and System-of-Systems (SoS) becomes a valued alternative to the economically prohibited and almost impossible prototype testing. In consideration of this problem, the presented work introduces a method for both modeling and simulation of a SoS. The method uses ontology with description logic reasoning to derive and narrow down a SoS design space which is further analyzed using Agent Based Simulation (ABS). A Search and Rescue (SAR) scenario is used as a case study to test the method. Measures of Effectiveness (MoE), based on the time it takes to find a rescue subject and the cost of doing so, are used to evaluate the SoS performances. The presented method is envisioned to be used early in the development of complex systems and SoS to increase the overall understanding of them.
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| 7. |
- Knöös Franzén, Ludvig, 1990-
(författare)
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A System of Systems View in Early Product Development : An Ontology-Based Approach
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The concept of system-of-systems is becoming increasingly common and relevant in many engineering applications. Today’s highly interconnected world entails that more and more systems have dependencies on other systems. This increasing number of interdependencies results in new levels of complexity that must be managed in the early development of new products. Different viewpoints must also be handled to understand the many layers of a system-of-systems and its surrounding context. An ever-changing future results in uncertainty about the operational environment but also other aspects, such as available technologies, which complicates the matter even further. Traditional approaches for early product development can be used to some extent, but the complexity, scale and sheer number of interconnections in system-of-systems require a holistic perspective to obtain an early understanding of the problem, design spaces, and multiple aspects involved. This dissertation aims to present a method that has been developed to address the demand for a more holistic system-of-systems view in early product development. Overall, the method consists of four parts that together show how design spaces for system-of-systems can be generated and later processed to find suitable solutions. Search and rescue operations have been used as examples of system-of-systems throughout this work and in the development of the presented method. The first two parts of the method are based on architecture frameworks and ontologies with description logic reasoning capabilities. An architecture framework is here used to break down system-of-system needs into functions to be fulfilled by constituent systems. Ontologies are thereafter used to represent the outcome and the resulting system-of-system design spaces with involved entities and their relationships. Description logic reasoning can subsequently be used to process the available design spaces and suggest suitable system-of-system solutions. The last two parts of the method build upon a concept exploration and estimation approach, together with visual analytics. The approach illustrates how individual system concepts can be estimated from an ontology-represented design space, and how visual analytics can be used to explore different system-of-system viewpoints at an early stage. Based on the outcomes of the presented method, this dissertation contributes a holistic take on early product development from a system-of-systems perspective.
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| 8. |
- Knöös Franzén, Ludvig, 1990-
(författare)
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An Ontological and Reasoning Approach to System of Systems
- 2021
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- System-of-Systems (SoS) are all around us and are becoming more common in today’s highly interconnected world. Systems are connected with other systems and have strong dependencies with their operational environments. This leads to an increased level of complexity and risk during product development. A holistic view, and an SoS perspective, is consequently needed in order to develop an early understanding of the available design spaces for new system solutions. This thesis suggests a method that has been developed for this purpose, and to meet the demand for a more holistic product development. Overall, the method consists of two correlated approaches that show how a design space for SoSs can be generated and later processed with, for example, design space reductions. Search and Rescue (SAR) operations have been used as examples of typical SoSs throughout this work and in the development of the presented method. An architecture framework has been used to introduce a standardized and consistent way of understanding the relationships that exist between needs, capabilities and functions. This approach can consequently be used to generate a design space of functions to be performed to meet the overarching needs of an SoS. The second approach has been based on ontology and description logic reasoning. Ontology has here been used to represent an SoS design space with, for example, available SAR assets and their relationships with the operational environment. An SoS representation in an ontology model introduces additional expressiveness and the design space processing capabilities needed for a holistic design process and product development. Based on these results, this thesis and its suggested method and approaches contribute to holistic product development from an SoS perspective.
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| 9. |
- Lundström, David, 1978-, et al.
(författare)
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RAVEN - A Subscale Radio Controlled Business Jet Demonstrator
- 2008
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Ingår i: proceedings from the ICAS 2008, CD-ROM. - Anchorage : International Council of the Aeronautical Sciences, (ICAS).
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Konferensbidrag (refereegranskat)abstract
- A dynamically scaled model of a Business-Jet has been build and is undergoing testing at Linköping University. The goal of the project was to understand the difficutlties of dynamic scaling and how to extract useful data from subscale flight testing. This paper presents the experience made during the projects up to the time of writing, and includes details from manufacturing, ground testing equipment such as car top testing, in flight data acquisition system design and preparation for the fligt testing.
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| 10. |
- Marcus, Carina, 1971-
(författare)
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Sensor and Signature Modeling for Aircraft Conceptual Development
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aircraft design process has several phases, the first of which is conceptual design. In this phase, models describing an aircraft concept’s properties are used to evaluate its function and identify designs that meet given requirements. Fighter aircraft are generally expected to be capable of communicating, delivering munitions and gathering data about their environment to gain situational awareness. The ability to avoid detection by hostile sensors can also be important, depending on the aircraft’s role.The design process of the aircraft itself has usually focused on an aircraft’s flight performance and ability to carry loads, e.g. munitions and extra fuel. While acceleration, rate of turn, maximum speed, and operational range are important parameters, the success of military missions also depends on sensor capabilities and signature levels. However, sensor installation and signature reduction measures can affect the aircraft and its flight performance. Whether an aircraft concept fulfills the requirements given is evaluated using simulations in appropriate scenarios. The concept’s performance is assessed using models of aircraft properties, weapon properties, sensor capabilities and signature levels. Models of the aircraft properties are usually connected dynamically, and respond to changes in such things as the size of the concept. However, sensor and signature models are often the result of a separate optimization process and are only statically connected to the aircraft model. The complete aircraft model can be improved by introducing sensor and signature models that dynamically describe both their functions, and their impact on the aircraft. Concurrent design of all the aircraft properties may improve the quality of results from scenario simulations. When models used in simulations contain parameters coupled to each other, analysis of the resulting data is particularly important because that is what supports a decision-maker’s design choice.Sensor and signature models, in some cases combined with flight performance models, have been used to test methodologies intended for use in conceptual aircraft design. The results show that even seemingly simple models can produce results that can make a significant contribution to the aircraft design process.
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