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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

On-Board Diagnostics over Ethernet

Moradpour Chahaki, Saeed January 2012 (has links)
Modern vehicles are more electrical than mechanical. As the vehicle industry goes on, more mechanical parts are being replaced by electrical components, e.g. x-by-wire. Weight and production costs could be the major factors in this revolution. To ensure the safety and in time response (meeting request’s deadline), the connection between these components is of great importance. Trying to find a protocol and standard that fits the vehicle industry to connect all ECUs, sensors and actuators together is not an easy task, since we are dealing with a system that has got a diverse type of traffic. Safety on the one hand and cost on the other hand are pushing the manufacturers to find the best networking protocol. In this report I am going to investigate the possibility and the risk of implementing on-board diagnostics over Ethernet. UDS (unified diagnostic services) and DoIP (diagnostic communication over Internet protocol) are the protocols that are going to be studied. To be more precise, I will investigate the possibility and the risk of UDS and DoIP implementation. The reason is that with the increasing number of ECUs and volume of data (parameter setting, downloading software, etc.,), the already implemented protocols and standards are not able to answer the required bandwidth. The wide acceptance and high bandwidth of Ethernet on one hand and its low cost infrastructure on the other hand has made Ethernet a candidate for this purpose.  The feasibility of Ethernet for in-vehicle network has already been investigated as I will show in the review of previous works. There are a couple of works that shows by using a suitable protocol in data link layer, we can meet the real-time requirement of a process. By reviewing these previous works we will find out that using Ethernet for vehicle on-board diagnostics is feasible. After investigating risks and manufacturer’s requirements along with worldwide legislations for the vehicle industry I will develop a DoIP gateway according to ISO 13400 which is connected to a CAN bus from one side and to a test tool via Ethernet from another side (Fig.1). UDS and DoIP protocols are implemented on both test tool and DoIP gateway. The practical part of the work is a complementary step in risk investigation that will be analysed. Having Ethernet as a carrier allows us to make use of different protocols, based on different needs like bandwidth, latency and real-time characteristics. This fact allows the network to have multi-type data which is usually the case with in-vehicle network. That is, we can use Ethernet not only for on-board diagnostics but also for other in-vehicle domains, such as the chassis, infotainment and comfort. At the end I will propose two models that will help the designers in this domain.
2

TimescaleDB för lagring av OBD-II-data / TimescaleDB for OBD-II data storage

Svensson, Alex, Wichardt, Ulf January 2022 (has links)
All cars support reading diagnostic data from their control units via the On-Board Diagnostics II protocol. For companies with large vehicle fleets it may be valuable to analyze this diagnostic data, but large vehicle fleets produce large amounts of data. In this thesis we investigated whether the time series database TimescaleDB is suitable for storing such data. In order to investigate this we tested and evaluated its insertion speed, query execution time and compression ratio. The results show that TimescaleDB is able to insert over 200 000 rows of data per second. They also show that the compression algorithm can speed up query execution by up to 134.5 times and reach a compression ratio of 9.1. Considering these results we conclude that TimescaleDB is a suitable choice for storing diagnostic data, but not necessarily the most suitable.
3

Improved Performance of Discrete Implementation of Switching Mode Controller for Urea-SCR

Mrunal Sunil Chavan (16613454) 19 July 2023 (has links)
<p>Diesel engines emit toxic gases like NOx and hydrocarbons. These gases need to be treated before they are released out the tailpipe. Thus, an aftertreatment system is installed which comprises of DOC, DPF and SCR. The DOC oxidizes the hydrocarbons and NO, the DPF traps the particulate matter and SCR reduces the NOx by reacting with NH3 at high temperatures. However, since NH3 is also a toxic gas, it cannot be released out the tailpipe in excess. It is important to inject an appropriate amount of NH3 so that it does not slip out the tailpipe. With increasingly stringent regulations on the emission limits of these toxic gases, control of SCR has become more necessary than before.</p> <p>In this thesis, the work done by previous members of the lab research group was improved upon. The objective remained the same, namely, keeping the NH3 slip under 50 ppm while maximizing NOx reduction. On initial inspection, it was realized that the entire controller had been designed and implemented in continuous time. Since the controller would be implemented digitally, with limited hardware sampling time, a discrete-time implementation as done via a DCU was created. The controller switched between two controllers – slip-based and storage-based. The slip-based controller was modified to include a feedforward term in the system so that the response time could be improved along with a feedback controller to eliminate any disturbances and steady-state error, using ammonia slip feedback as measured by an NH3 sensor. It aims at keeping the maximum ammonia slip under 50 ppm. The storage controller is a feedback controller which tries to limit the ammonia storage based on the values fed by a lookup table. This lookup table is a simplified table that determines the maximum ammonia storage at any given instant based on the catalyst bed temperature. The feedback controller gains for both controllers were determined based on a linearized plant model since the initial gains were ineffective with the discretized model. The initial switching mode controller that switches between slip control and storage control switched too frequently between the controllers, thereby affecting controller performance. A switching logic was implemented to limit the number of switches. A switch will be permitted only if the previous switch occurred over a certain time. By implementing all the subparts together in the controller, incremental improvements were prominent. In the end, the performance by implementing the proposed idea was distinctly better. The metrics considered for performance comparison are the number of switches and the ability to maximize slip up to 50 ppm. Parameter error was also studied as well and its effect on the controller performance was analyzed. The data when tested against sets of underestimated, overestimated and mixed estimates for the plant parameters resulted in the underestimated parameters to work within the scope of the objective. The controller was able to compensate for the underdosing. Overestimation caused overdosing in the system which led to spikes in the NH3 slip. Thus, it is better to underestimate the plant parameters than overestimate them.</p>
4

Wireless On-Board Diagnostics

Schirninger, Rene, Zeppetzauer, Stefan January 2005 (has links)
<p>Wireless On-board diagnostics functionality, which is a future outlook to vehicle system </p><p>parameter analysis, enables measurements and controlling without the limitation of a physical </p><p>connector. Today every vehicle must by law provide the possibility to analyze engine and </p><p>emission related parameters (OBD II). The wireless connection requires a high security level </p><p>to prevent unauthorized communication establishment with the truck’s bus system. The aim </p><p>of the project is to make a survey of the available security mechanisms and to find the most </p><p>promising solutions. Furthermore, several usage scenarios and access right levels are </p><p>specified and a risk analysis of the whole system is made. The greatest challenge is the </p><p>specification and implementation of a proper key-exchange mechanism between the analyzing </p><p>device and the truck’s bus system, which is therefore carried out with the highest possible </p><p>level of awareness. Consequently several different concepts have been formulated based on </p><p>the different usage scenarios.</p>
5

Wireless On-Board Diagnostics

Schirninger, Rene, Zeppetzauer, Stefan January 2005 (has links)
Wireless On-board diagnostics functionality, which is a future outlook to vehicle system parameter analysis, enables measurements and controlling without the limitation of a physical connector. Today every vehicle must by law provide the possibility to analyze engine and emission related parameters (OBD II). The wireless connection requires a high security level to prevent unauthorized communication establishment with the truck’s bus system. The aim of the project is to make a survey of the available security mechanisms and to find the most promising solutions. Furthermore, several usage scenarios and access right levels are specified and a risk analysis of the whole system is made. The greatest challenge is the specification and implementation of a proper key-exchange mechanism between the analyzing device and the truck’s bus system, which is therefore carried out with the highest possible level of awareness. Consequently several different concepts have been formulated based on the different usage scenarios.
6

Μελέτη συστήματος διαγνωστικών αυτοκινήτων (OBD-II)

Κρίβας, Ανδρέας, Γιατράκης, Εμμανουήλ 10 June 2014 (has links)
Στην παρούσα διπλωματική εργασία σχεδιάστηκε, μελετήθηκε και υλοποιήθηκε ένα σύστημα διαγνωστικών αυτοκινήτου ή αλλιώς ένα σύστημα On Board Diagnostics II (OBD-II), όπως είναι η διεθνής του ονομασία. Ένα τέτοιο σύστημα έχει καταστεί απαραίτητο, λόγω της πολυπλοκότητας των αυτοκινήτων σήμερα, σε μια ευρεία κατηγορία επαγγελματιών, που ξεκινάει από τους κατασκευαστές αυτοκινήτου μέχρι και το κάθε συνεργείο, αλλά και τον εκάστοτε ιδιώτη. Κύριοι στόχοι του είναι η πληροφόρηση του χρήστη για οποιαδήποτε παράμετρο του οχήματος και ο εντοπισμός και η ένδειξη τυχόν βλαβών. Για την επίτευξη των στόχων αυτών, σχεδιάστηκε και υλοποιήθηκε με τη μορφή πλακέτας ένα σύστημα το οποίο είναι υπεύθυνο για τη σωστή αποστολή και λήψη των μηνυμάτων μεταξύ του υπολογιστή και του οχήματος. Επιπλέον, αναπτύχθηκε το απαραίτητο λογισμικό για τη χρήση του συστήματος και όλων των δυνατοτήτων του. Για το σωστό έλεγχο τόσο του κυκλώματος όσο και του λογισμικού, χρησιμοποιήσαμε έναν προσομοιωτή ECU αυτοκινήτου. / In this diploma thesis, an On Board Diagnostics system (OBD-II) was studied, designed and created. This type of system is of utmost importance to a great variety of users such as professional engineers and individuals. Its main purposes are to inform the user about all the different parameters of the vehicle and to identify potential malfunctions. To accomplish these tasks, a PCB circuit was designed and manufactured, which is responsible for the correct transmission and reception of OBD-II messages between a developed PC software and the vehicle. In order to test the circuit and the designed application, an ECU Simulator was used.
7

Využití diagnostické sady VAG-COM PROFI v soudním inženýrství / Use of VAG-COM PROFI Diagnostic Kit in Forensic Engineering

Wertheim, Adolf January 2014 (has links)
The thesis deals with possibilities of application of VAG-COM PROFI diagnostic kit in forensic engineering. After defining a theoretical basis, according to possibilities of evaluation of technical condition of a vehicle, the thesis is focused on applying diagnostic methods using above mentioned diagnostic kit. With respect to opportunities of identification of driving parameters, possibility of acceleration measurement and estimation of engine power are introduced. Describing of methodology and making the final statement are contained in the thesis as a part of every single measurement.
8

Uncertainty Analysis of Resistive Soot Sensors for On-BoardDiagnostics of Automotive Particulate Filters

Baradwaj, Nithin V. January 2013 (has links)
No description available.
9

The process of OBD certification : a comparative study between Euro VI and CARB / Processen för OBD certifiering : en komparativ studie mellan Euro VI och CARB

Anayati, Shilan, Gaber, Mohammed January 2019 (has links)
Purpose: The purpose of this study is to compare the legal requirements for Euro VI and CARB regarding OBD certification in order to identify the challenges that may come for a manufacturer’s move from Euro VI classified heavy-duty engines to engines that meet the requirements of CARB. Furthermore, the study also aims to identify the effects that these challenges will have on the organisation. Research question: What type of challenges arise for a manufacturing company when developing an OBD certification process according to the requirements from CARB compared to Euro VI and how do these challenges affect the organisation? Method: The nature of this study was qualitative with a deductive method as an approach, where theories and empirical findings interacts. The theoretical framework is divided into two parts, in which the first part is obtained from scientific articles and books and the second part from legislations. The empirical data was gathered from interviews at a case study company and the information was thematically analysed. Conclusion: This study concludes that the movement from Euro VI to CARB standards will result in comprehensive changes for a company’s OBD process itself as well as organisational changes within the company. There will be a need to establish new processes and new ways of working within the organisation which can lead to comprehensive coordination difficulties that should be taken into consideration. In conclusion, it is as important to consider the effects of the changes that this movement will bring on the company and the actors within, as it is with the implementation of the process itself. / Syfte: Syftet med denna studie är att jämföra lagkraven för Euro VI och CARB angående OBD certifieringen och därmed identifiera de utmaningar som kan uppstå i och med övergången från Euro VI klassificerade motorer till motorer som uppfyller kraven från CARB. Vidare syftar studien även till att undersöka hur dessa utmaningar påverkar organisationen. Forskningsfråga: Vilka utmaningar uppstår för ett tillverkande företag vid utveckling av en OBD certifieringsprocess enligt lagkrav från CARB i jämförelse med Euro VI och hur påverkar dessa utmaningar organisationen? Metod: Denna studie är av en kvalitativ karaktär som är baserad på en deduktiv forskningsmetod. Den teoretiska referensramen är uppdelat i två sektioner, vari den första är baserad på vetenskapliga artiklar och böcker och den andra från lagkrav. Empiriska data har samlats från intervjuer på fallstudieföretaget och metoden som har använts för att analysera materialet är tematisk analys. Slutsats: Denna studie konkluderar att övergången från Euro VI till CARB lagkrav resulterar i omfattande förändringar för företagets OBD process och bringar organisationsförändringar inom företaget. Det kommer att finnas ett behov av att etablera nya processer och nya arbetssätt inom organisationen som kan leda till omfattande samordningsproblem som bör has i åtanke. Sammanfattningsvis är det av yttersta vikt att ta hänsyn till de organisationsförändringarna som förväntas uppstå i och med denna förändring och inte enbart fokusera på att implementera en ny process.
10

Data-based on-board diagnostics for diesel-engine NOx-reduction aftertreatment systems

Atharva Tandale (15351352) 27 April 2023 (has links)
<p>The NOx conversion efficiency of a combined Selective Catalytic Reduction and</p> <p>Ammonia Slip Catalyst (SCR-ASC) in a Diesel Aftertreatment (AT) system degrades with</p> <p>time. A novel model-informed data-driven On-Board Diagnostic (OBD) binary classification</p> <p>strategy is proposed in this paper to distinguish an End of Useful Life (EUL) SCR-ASC catalyst</p> <p>from Degreened (DG) ones. An optimized supervised machine learning model was used for the</p> <p>classification with a calibrated single-cell 3-state Continuous Stirred Tank Reactor (CSTR)</p> <p>observer used for state estimation. The method resulted in 87.5% classification accuracy when</p> <p>tested on 8 day-files from 4 trucks (2 day-files per truck; 1 DG and 1 EUL) operating in realworld on-road conditions.</p>

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