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The application of multi-attribute optimisation as a systems engineering tool in an automotive CAE environmentSutton, Paul January 2012 (has links)
Multi-Attribute Optimisation (MAO) is proposed as a tool for delivering high value products within the systems engineering approach taken in the automotive industry. This work focuses on MAO methods that use Computer Aided Engineering (CAE) analyses to build a metamodel of system behaviour. A review of the literature and current Jaguar Land Rover optimisation methods showed that the number of samples required to build a metamodel could be estimated using the number of input variables. The application of these estimation methods to a concept airbox design showed that this guidance may not be sufficient to fully capture the complexity of system behaviour in the metamodelling method. The use of the number of input variables and their ranges are proposed as a new approach to the scaling of sample sizes. As a corollary to the issue of the sample size required for accurate metamodelling, the sample required to estimate the error was also examined. This found that the estimation of the global error by additional samples may be impractical in the industrial context. CAE is an important input to the MAO process and must balance the efficiency and accuracy of the model to be suitable for application in the optimisation process. Accurate prediction of automotive attributes may require the use of new CAE techniques such as multi-physics methods. For this, the fluid structure interaction assessment of the durability of internal components in the fuel tank due to slosh was examined. However, application of the StarCD-Abaqus Direct couple and Abaqus Combined Eularian Lagrangian was unsuitable for this fuel slosh application. Further work would be required to assess the suitability of other multi-physics methods in an MAO architecture. Application of the MAO method to an automotive airbox shows the potential for improving both product design and lead time.
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Use of domain-specific language in test automationHussain, Ambreen 04 1900 (has links)
The primary aim of this research project was to investigate techniques to replace the complicated process of testing embedded systems in automotive domain. The multi-component domain was composed of different hardware to be used in testing procedure which increased the level of difficulty in testing for an operator. As a result, an existing semi-automated testing procedure was replaced by more simpler and efficient framework (ViBATA). A key step taken in this scenario was the replacement of manual GUI interface with the scriptable one to enhance the automation. This was achieved by building a Domain-specific language which allowed test definition in the form of human readable scripts which could be stored for later use.
A DSL is a scripting language defined for a particular domain with compact expressiveness. In this case the domain is testing embedded systems in general and automotive systems in particular. The final product was a test case specification document in the form of XML as an output of generated code from this DSL which will be input to ViBATA to make test specification component automated.
In this research a comparative analysis of existing DSLs for alternative domains and investigation of their applicability to the presented domain was also performed. The technologies used in this project are Xtext to define the DSL grammar, Xtend to generate code in Java and Simple framework to generate output in XML. The stages involved in DSL development and how these stages were implemented is covered in this thesis.
The developed DSL for this domain is tested for automotive and calculator systems in this thesis which proved that this is more general and flexible. The DSL is consistent, efficient and automated test specification component of testing framework in embedded systems.
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Towards a framework for engineering big data: An automotive systems perspectiveByrne, Thomas J., Campean, Felician, Neagu, Daniel 05 1900 (has links)
Yes / Demand for more sophisticated models to meet big data expectations require significant data repository obligations, operating concurrently in higher-level applications. Current models provide only disjointed modelling paradigms. The proposed framework addresses the need for higher-level abstraction, using low-level logic in the form of axioms, from which higher-level functionality is logically derived. The framework facilitates definition and usage of subjective structures across the cyber-physical system domain, and is intended to converge the range of heterogeneous data-driven objects.
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Troubleshooting Trucks : Automated Planning and Diagnosis / Felsökning av lastbilar : automatiserad planering och diagnosWarnquist, Håkan January 2015 (has links)
This thesis considers computer-assisted troubleshooting of heavy vehicles such as trucks and buses. In this setting, the person that is troubleshooting a vehicle problem is assisted by a computer that is capable of listing possible faults that can explain the problem and gives recommendations of which actions to take in order to solve the problem such that the expected cost of restoring the vehicle is low. To achieve this, such a system must be capable of solving two problems: the diagnosis problem of finding which the possible faults are and the decision problem of deciding which action should be taken. The diagnosis problem has been approached using Bayesian network models. Frameworks have been developed for the case when the vehicle is in the workshop only and for remote diagnosis when the vehicle is monitored during longer periods of time. The decision problem has been solved by creating planners that select actions such that the expected cost of repairing the vehicle is minimized. New methods, algorithms, and models have been developed for improving the performance of the planner. The theory developed has been evaluated on models of an auxiliary braking system, a fuel injection system, and an engine temperature control and monitoring system.
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Optimizing the Automotive Security Development Process in Early Process Design PhasesJakobs, Christine 02 August 2023 (has links)
Security is a relatively new topic in the automotive industry. In the former days, the only security defense methods were the engine immobilizer and the anti-theft alarm system. The rising connection of vehicles to external networks made it necessary to extend the security effort by introducing security development processes. These processes include, amongothers, risk analysis and treatment steps. In parallel, the development of ISO/SAE 21434 and UN-ECE No. R155 started. The long development cycles in the automotive industry made it necessary to align the development processes' early designs with the standards' draft releases.
This work aims to design a new consistent, complete and efficient security development process, aligned with the normative references. The resulting development process design aligns with the overall development methodology of the underlying, evaluated development process. Use cases serve as a basis for evaluating improvements and the method designs. This work concentrates on the left leg of the V-Model. Nevertheless, future work targets extensions for a holistic development
approach for safety and security.:I. Foundation
1. Introduction
2. Automotive Development
3. Methodology
II. Meta-Functional Aspects
4. Dependability as an Umbrella-Term
5. Security Taxonomy
6. Terms and Definitions
III. Security Development Process Design
7. Security Relevance Evaluation
8. Function-oriented Security Risk Analysis
9. Security Risk Analysis on System Level
10. Risk Treatment
IV. Use Cases and Evaluation
11. Evaluation Criteria
12. Use Case: Security Relevance Evaluation
13. Use Case: Function-oriented Security Risk Analysis
14. Use Case: System Security Risk Analysis
15. Use Case: Risk Treatment
V. Closing
16. Discussion
17. Conclusion
18. Future Work
Appendix A. Attacker Model Categories and Rating
Appendix B. Basic Threat Classes for System SRA
Appendix C. Categories of Defense Method Properties
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END-TO-END TIMING ANALYSIS OF TASK-CHAINSJin, Zhiqun, Zhu, Shijie January 2017 (has links)
Many automotive systems are real-time systems, which means that not only correct operationsbut also appropriate timings are their main requirements. Considering the in uence that end-to-end delay might have on the performance of the systems, the calculation of it is of necessity.Abundant techniques have actually been proposed, and some of them have already been applied intopractical systems. In spite of this, some further work still needs to be done. The target of thisthesis is to evaluate and compare two end-to-end timing analysis methods from dierent aspectssuch as data age, consumption time, and then decide which method is a prior choice for end-to-end timing analysis. The experiments can be divided into three blocks, system generation andend-to-end delay calculation by two methods respectively. The experiments focus on two kinds ofperformance parameters, data age and the consumption time that these two methods cost duringtheir execution. By changing the system generating parameters like task number and periods, thechanges of performances of the two methods are analyzed. The performances of the two dierentmethods are also compared when they are applied into the same automotive systems. According tothe results of the experiments, the second method can calculate more accurate data age and consumeless time than the rst method does.
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End-to-end Timing Analysis of Task-ChainsZhiqun, Jin, Shijie, Zhu January 2017 (has links)
Many automotive systems are real-time systems, which means that not only correct operationsbut also appropriate timings are their main requirements. Considering the in uence that end-to-end delay might have on the performance of the systems, the calculation of it is of necessity.Abundant techniques have actually been proposed, and some of them have already been applied intopractical systems. In spite of this, some further work still needs to be done. The target of thisthesis is to evaluate and compare two end-to-end timing analysis methods from dierent aspectssuch as data age, consumption time, and then decide which method is a prior choice for end-to-end timing analysis. The experiments can be divided into three blocks, system generation andend-to-end delay calculation by two methods respectively. The experiments focus on two kinds ofperformance parameters, data age and the consumption time that these two methods cost duringtheir execution. By changing the system generating parameters like task number and periods, thechanges of performances of the two methods are analyzed. The performances of the two dierentmethods are also compared when they are applied into the same automotive systems. According tothe results of the experiments, the second method can calculate more accurate data age and consumeless time than the rst method does.
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[en] CONTROL STRATEGIES APPLIED TO GROUND VEHICLES HANDLING PROBLEM IN PRE-DEFINED CLOSED TRAJECTORIES / [pt] ESTRATÉGIAS DE CONTROLE APLICADAS AO PROBLEMA DE DIRIGIBILIDADE DE VEÍCULOS TERRESTRES EM TRAJETÓRIAS FECHADAS PRÉ-DEFINIDASFERNANDO HEY 09 October 2008 (has links)
[pt] Apresenta-se o uso das ferramentas lineares de Controle
Clássico (Lugar Geométrico das Raízes) e Moderno
(Realimentação de Estado e de Saída e Alocação de Pólos)
para estabelecer os ajustes dos controladores adotados no
problema de acompanhamento de trajetórias em traçados
fechados por veículos terrestres, procurando reproduzir o
comportamento do ser humano no comando deste tipo de
sistema. Os modelos adotados para o veículo são lineares
(funções de transferência e matrizes de estado e de
entrada), porém a caracterização da trajetória fechada é
geometricamente não-linear. Verifica-se deste modo como o
projeto de um controle linear satisfaz as condições não
lineares associadas. Os conceitos e ferramentas conhecidos
são aplicados em diversos tipo de traçados,
para diferentes condições do veículo - velocidade, limites
de esterçamento, etc - e, a partir das simulações
realizadas, são analisadas as características de
comportamento do veículo - acelerações, estabilidade, etc -
e comparadas as previsões dos projetos lineares com os
resultados encontrados. É feita ainda uma
breve introdução ao emprego do Controle Ótimo no problema de
acompanhamento de traçados, utilizando um modelo bastante
simplificado do veículo, e verificando as condições
necessárias para se estabelecer a trajetória
ótima em um traçado aberto, dado como critério o tempo
mínimo para percorrê-lo. / [en] The use of classic and modern linear control tools (root
locus and output regulation) is presented to determine the
parameters of controllers used to follow a pre-defined
closed path, in a way to approach the vehicle behavior and
human actions when driving a car. The car is represented by
linear models (transfer functions, state-space matrix), but
the relation between the car and the closed path
is non linear. It is verified how the project of a linear
controller deals with the non linear characteristics of the
closed loop. The concepts and tools of linear control
are applied to some kinds of paths in different vehicle
conditions (speed, steering angle limits, etc), and the
results of simulations show the characteristics of the car,
like accelerations, stability and position on the track.
It`s also presented a little introduction to the problem of
determine an optimal trajectory to run a corner,
given the initial and final velocities and initial and
final positions. In this case a very simple model is
considered and the solution is based on open paths analysis.
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Safety/Security Co-design for Automotive CAN BusesZhang, Mingqing 10 December 2024 (has links)
The automotive industry heavily relies on the controller area network (CAN) due to its low cost and robustness. However, as vehicle connectivity grows, CAN buses become more vulnerable to cyberattacks such as spoofing, sniffing, replay, and denial of service (DoS), compromising both safety and (cyber-)security. Most existing attempts to secure CAN buses necessitate modifications to the hardware or protocol, which increase costs and complicate implementation, or they employ security schemes that negatively impact timing behavior and safety for both passengers and other road participants. To address this problem, we first propose a safety/security co-design approach based on combining a technique we call periodic authenticated encryption. On the other hand, DoS attacks on CAN buses can typically only be mitigated rather than completely rejected, due to CAN's inherent characteristics. We hence propose a priority-raise approach to this aim. Further, securing CAN buses requires sending additional frames, which frames undergo individual arbitration processes, further increasing delay. To alleviate this situation, we propose an ID mirroring technique. Finally, to accommodate to varying timing requirements in safety-critical applications, we propose a dynamic encryption switching approach. To evaluate the efficacy of these techniques, we conducted experiments on real hardware and carried out extensive simulations using MATLAB/Simulink and OMNeT++. Additionally, we presented various case studies involving electronic stability control (ESC), emergency braking, adaptive cruise control (ACC), and cooperative driving. Our findings demonstrate that the proposed techniques effectively reduce transmission delays while mitigating or preventing all major cyberattacks on the CAN bus. Furthermore, these techniques enable us to meet typical automotive deadlines on CAN buses, fulfilling both safety and security requirements within automotive systems.:Introduction
Fundamentals
Related work
Case studies
Rejecting sniffing, spoofing and replay attacks on CAN buses
Mitigating DoS attacks on CAN buses
Improving timing on secured CAN buses
Evaluation
Concluding remarks
Bibliography
Appendix
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A Method for Optimised Allocation of System Architectures with Real-time ConstraintsMarcus, Ventovaara, Arman, Hasanbegović January 2018 (has links)
Optimised allocation of system architectures is a well researched area as it can greatly reduce the developmental cost of systems and increase performance and reliability in their respective applications.In conjunction with the recent shift from federated to integrated architectures in automotive, and the increasing complexity of computer systems, both in terms of software and hardware, the applications of design space exploration and optimised allocation of system architectures are of great interest.This thesis proposes a method to derive architectures and their allocations for systems with real-time constraints.The method implements integer linear programming to solve for an optimised allocation of system architectures according to a set of linear constraints while taking resource requirements, communication dependencies, and manual design choices into account.Additionally, this thesis describes and evaluates an industrial use case using the method wherein the timing characteristics of a system were evaluated, and, the method applied to simultaneously derive a system architecture, and, an optimised allocation of the system architecture.This thesis presents evidence and validations that suggest the viability of the method and its use case in an industrial setting.The work in this thesis sets precedence for future research and development, as well as future applications of the method in both industry and academia.
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