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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Aircraft Systems Modeling : Model Based Systems Engineering in Avionics Design and Aircraft Simulation

Andersson, Henric January 2009 (has links)
<p>Aircraft developers like other development and manufacturing companies, are experiencing increasing complexity in their products and growing competition in the global market. One way to confront the challenges is to make the development process more efficient and to shorten time to market for new products/variants by using design and development methods based on models. Model Based Systems Engineering (MBSE) is introduced to, in a structured way, support engineers with aids and rules in order to engineer systems in a new way.</p><p>In this thesis, model based strategies for aircraft and avionics development are studied. A background to avionics architectures and in particular Integrated Modular Avionics is described. The integrating discipline Systems Engineering, MBSE and applicable standards are also described. A survey on available and emerging modeling techniques and tools, such as Hosted Simulation, is presented and Modeling Domains are defined in order to analyze the engineering environment with all its vital parts to support an MBSE approach.</p><p>Time and money may be saved by using modeling techniques that enable understanding of the engineering problem, state-of-the-art analysis and team communication, with preserved or increased quality and sense of control. Dynamic simulation is an activity increasingly used in aerospace, for several reasons; to prove the product concept, to validate stated requirements, and to verify the final implementation. Simulation is also used for end-user training, with specialized training simulators, but with the same underlying models. As models grow in complexity, and the set of simulation platforms is expanded, new needs for specification, model building and configuration support arise, which requires a modeling framework to be efficient.</p>
2

Interactive SysML Diagrams using a Web Browser

Nilsson, Jesper January 2020 (has links)
Managing and maintaining a system requires knowledge of its structure, along with the relations and interactions between its components. Systems Model- ing Language, SysML, is a language used to describe systems and enables the practice of Model-based Systems Engineering (MBSE). Having a model of a system is one key to understand the system and useful for future management and maintenance. Apart from being an advanced language, the tools that support SysML are often both advanced and expensive. This work was commissioned to create a different tool, a tool that is free, web-based, and interactive. The tool not only allows the user to look at the system but also explore the system’s design and the interesting parts of its internal structure. The tool uses a textual input to generate interactive diagrams with the possibility to filter out redundant information. Since it is available in a web browser, one can share their textual input instead of sharing pictures of diagrams. The textual input makes it possible to share a system structure in a new way, as well as to make the system model easier to maintain.
3

Application of an innovative MBSE (SysML-1D) co-simulation in healthcare

Kalvit, Kalpak 05 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI)
4

Approche d’ingénierie systèmes pour l’intégration de la fabricabilité dans le processus de conception des systèmes mécatroniques / Systems engineering approach for the integration of manufacturability in the design process of mechatronic systems

Borchani, Mohamed 03 July 2019 (has links)
L’originalité de notre travail consiste à développer une approche qui intègre l’ingénierie systèmes basée sur les modèles (MBSE) avec les principes de l’approche SBCE afin de réduire les boucles itératives entre les concepteurs inexpérimentés, les fabricants et les experts. D’autres parties prenantes participent également au développement du produit afin d’assurer environnement d’ingénierie simultanée. Cette approche offre un grand potentiel pour gérer les aspects de fabricabilité et de fiabilité, en raison de la capacité à développer des connaissances en parallèle, en particulier pour les technologies avancées et non matures. L’avantage d’utilisation des principes du SBCE est d’offrir des possibilités de communication entre les parties prenantes au début de la phase de conception. SysML est utilisé comme langage descriptif pour représenter les différentes phases de cette approche. Pour étudier la robustesse ces système, nous avons développé un modèle intitulé «Model Based for Robustness Analysis» (MBRA) qui a pour objectif de filtrer les solutions faibles ou coûteuses au fil du temps et d’assister l’ingénieur système lors de l'adoption d’une étude de compromis. Pour l’étude de la fabricabilité des systèmes complexes, nous avons développé un autre modèle intitulé « Model Based for Manufacturability analysis » / The originality of our work is to develop an approach that integrates model-based systems engineering (MBSE) with the principles of the SBCE approach to reduce iterative loops between inexperienced designers, manufacturers, and experts. Other stakeholders are also involved in product development to ensure simultaneous engineering environment. This approach offers great potential for managing manufacturability and reliability aspects, due to the ability to develop parallel knowledge, especially for advanced and non-mature technologies. The advantage of using SBCE principles is to provide opportunities for communication between stakeholders early in the design phase. SysML is used as a descriptive language to represent the different phases of this approach. To study the robustness of these systems, we have developed a model called "Model Based for Robustness Analysis" (MBRA) which aims to filter low or expensive solutions over time and to assist the system engineer when adopting a trade-offs study. For the assessment of the manufacturability of complex systems, we have developed another model entitled "Model Based for Manufacturability analysis"
5

Investigating Validation of a Simulation Model for Development and Certification of Future Fighter Aircraft Fuel Systems

Vilhelmsson, Markus, Strömberg, Isac January 2016 (has links)
In this thesis a method for verification, validation and uncertainty quantification (VV&amp;UQ) has been tested and evaluated on a fuel transfer application in the fuel rig currently used at Saab. A simplified model has been developed for the limited part of the fuel system in the rig that is affected in the transfer, and VV&amp;UQ has been performed on this model. The scope for the thesis has been to investigate if and how simulation models can be used for certification of the fuel system in a fighter aircraft. The VV&amp;UQ-analysis was performed with the limitation that no probability distributions for uncertainties were considered. Instead, all uncertainties were described using intervals (so called epistemic uncertainties). Simulations were performed on five different operating points in terms of fuel flow to the engine with five different initial conditions for each, resulting in 25 different operating modes. For each of the 25 cases, the VV&amp;UQ resulted in a minimum and maximum limit for how much fuel that could be transferred. 6 cases were chosen for validation measurements and the resulting amount of fuel transferred ended up between the corresponding epistemic intervals. Performing VV&amp;UQ is a time demanding and computationally heavy task, which quickly grows as the model becomes more complex. Our conclusion is that a pilot study is necessary, where time and costs are evaluated, before choosing to use a simulation model and perform VV&amp;UQ for certification. Further investigation of different methods for increasing confidence in simulation models is also needed, for which VV&amp;UQ is one suitable option.
6

Evaluating ARCADIA/Capella vs. OOSEM/SysML for System Architecture Development

Alai, Shashank P. 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Systems Engineering is catching pace in many segments of product manufacturing industries. Model-Based Systems Engineering (MBSE) is the formalized application of modeling to perform systems engineering activities. In order to effectively utilize the complete potential of MBSE, a methodology consisting of appropriate processes, methods and tools is a key necessity. In the last decade, several MBSE projects have been implemented in industries varying from aerospace and defense to automotive, healthcare and transportation. The Systems Modeling Language (SysML) standard has been a key enabler of these projects at many companies. Although SysML is capable of providing a rich representation of any system through various viewpoints, the journey towards adopting SysML to realize the true potential of MBSE has been a challenge. Among all, one of the common roadblocks faced by systems engineers across industries has been the software engineering-based nature of SysML which leads to difficulties in grasping the modeling concepts for people that do not possess a software engineering background. As a consequence, developing a system (or a system of systems) architecture model using SysML has been a challenging task for many engineers even after a decade of its inception and multiple successive iterations of the language specification. Being a modeling language, SysML is method-agnostic, but its associated limitations outweigh the advantages. ARCADIA (Architecture Analysis and Design Integrated Approach) is a systems and software architecture engineering method based on architecture-centric and model-based engineering activities. If applied properly, ARCADIA allows for a very effective way to model the architecture of multi-domain systems, and overcome many of the limitations faced in traditional SysML implementation. This thesis evaluates the architecture development capabilities of ARCADIA/Capella versus SysML following the Object-Oriented Systems Engineering Method (OOSEM). The study focuses on the key equivalences and differences between the two MBSE solutions from a model development perspective and provides several criteria to evaluate their effectiveness for architecture development using a conceptual case of Adaptive Cruise Control (ACC). The evaluation is based on three perspectives namely, architecture quality, ability to support key process deliverables, and the overall methodology. Towards this end, an industry-wide survey of MBSE practitioners and thought leaders was conducted to identify several concerns in using models but also to validate the results of the study. The case study demonstrates how the ARCADIA/Capella approach addresses several challenges that are currently faced in SysML implementation. From a process point of view, ARCADIA/Capella and SysML equally support the provision of the key deliverable artifacts required in the systems engineering process. However, the candidate architectures developed using the two approaches show a considerable difference in various aspects such as the mapping of the form to function, creating functional architectures, etc. The ARCADIA/Capella approach allows to develop a ‘good’ system architecture representation efficiently and intuitively. The study also provides answers to several useful criteria pertaining to the overall candidate methodologies while serving as a practitioner’s reference in selecting the most suitable approach.
7

Hydrogen Fuel Cell on a Helicopter: A System Engineering Approach

January 2016 (has links)
abstract: Hydrogen fuel cells have been previously investigated as a viable replacement to traditional gas turbine auxiliary power unit onboard fixed wing commercial jets. However, so far no study has attempted to extend their applicability to rotary wing aircrafts. To aid in the advancement of such innovative technologies, a holistic technical approach is required to ensure risk reduction and cost effectiveness throughout the product lifecycle. This paper will evaluate the feasibility of replacing a gas turbine auxiliary power unit on a helicopter with a direct hydrogen, air breathing, proton exchange membrane fuel cell, all while emphasizing a system engineering approach that utilize a specialized set of tools and artifacts. / Dissertation/Thesis / Masters Thesis Engineering 2016
8

ENABLING REUSABILITY OF A SPACECRAFT DESIGN TOOLSET VIA MBSE

Andrew Brinton Lang (10712232) 28 April 2021 (has links)
<div><div><div><p>As technology advances, so does the complexity of engineering projects. Systems en- gineering has evolved with these technological advances as a means of coping with this complexity. Traditionally, systems engineers use separate documents to track all project in- formation. This trend continues today, as projects are becoming more complex than before and the traditional document based approach is now seen as time consuming and error prone. Model based Systems engineering (MBSE) is a systems engineering approach that seeks to incorporate all project information into a single source of truth that can be thought of as a model. However, there are several challenges that face widespread MBSE adoption, includ- ing data transfer incompatibilities between MBSE and engineering discipline models. These incompatibilities are a major focus of this thesis. One goal of this thesis is to demonstrate the addition of a translation framework between MBSE and the Modeling Architectures and Parameterization for Spacecraft (MAPS) environment. The translation framework takes information read from System Modeling Language (SysML) diagrams and converts it into a representation suitable for the MAPS environment. Adding a translation framework en- ables more rapid analysis of different architectures and allows more users to interact with the MAPS environment. This thesis also seeks a method by which to evaluate MBSE and systems engineering tools. A qualitative framework is created based on rigor in systems en- gineering. The rigor evaluation framework specifically targets weaknesses commonly found in MBSE to enable users to find better directions for these tools. The effectiveness of the translation framework is shown via a demonstration case. Additionally, the rigor evalua- tion framework is applied to the translation framework. This application results in several recommendations for improvements and demonstrates the evaluation framework’s ability to find and address problem areas in MBSE tools.</p></div></div></div>
9

Modular and Deployable Solution for Passing Hazardous Roads

Short, Nicholas 01 April 2022 (has links)
The developing world often relies on low-water crossings on unpaved roads in place of bridges for vehicle river crossings and impoverished communities suffer disproportionately more from road shut-downs. This project defines a modular and deployable bridge solution to combat low-water crossing hazards in undeveloped road systems in year-round conditions using Systems Engineering and related methodologies to architect the solution.
10

Nonlinear design, modeling and simulation of magneto rheological suspension: a control system and systems engineering approach

Zambare, Hrishikesh B. 12 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Suspension has been the most important subsystem of the vehicle viewed as a system. The ride comfort and vehicle handling performance are affected by the suspension design. Automotive technology has been continuously incorporating developments over the past few decades to provide the end users with a better comfort of driving. Multi-objective optimization of MR damper with objective function of maximizing damping force generated by MR damper with the geometrical parametric constraint function is achieved in this research using pattern search optimization technique. Research focuses on design, modeling, and simulation of active suspension using non-linear theory of the Magneto-Rheological (MR) damper with consideration of the hysteresis behavior for a quarter car model. The research is based on the assumption that each wheel experiences same disturbance excitation. Hysteresis is analyzed using Bingham, Dahl’s, and Bouc-Wen models. Research includes simulation of passive, Bingham, Dahl, and Bouc-wen models. Modeled systems are analyzed for the six road profiles, including road type C according to international standards ISO/TC108/SC2N67. Furthermore, the comparative study of the models for the highest comfort with less overshoot and settling time of vehicle sprung mass are executed. The Bouc-Wen model is 36.91 percent more comfortable than passive suspension in terms of damping force requirements and has a 26.16 percent less overshoot, and 88.31 percent less settling time. The simulation of the Bouc-Wen model yields a damping force requirement of 2003 N which is 97.63 percent in agreement with analytically calculated damping force generated by MR damper. PID controller implementation has improved the overshoot response of Bouc-Wen model in the range of 17.89 percent-81.96 percent for the different road profiles considered in this research without compromising on the settling time of system. PID controller implementation further improves the passenger comfort and vehicle ride handling capabilities. The interdisciplinary approach of systems engineering principles for the suspension design provides unique edge to this research. Classical systems engineering tools and MBSE approach are applied in the design of the MR damper. Requirement traceability successfully validates the optimized MR damper.

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