University of Warwick institutional repository: http://go.warwick.ac.uk/wrap A Thesis Submitted for the Degree of EngD at the University of Warwick http://go.warwick.ac.uk/wrap/41852 This thesis is made available online and is protected by original copyright. Please scroll down to view the document itself. Please refer to the repository record for this item for information to help you to cite it. Our policy information is available from the repository home page. Engineering Doctorate Innovation Report Design of In-Vehicle Networked Control System Architectures through the Use of New Design to Cost and Weight Processes Christopher Patrick Quigley This work has been submitted in partial fulfilment of the requirements for the degree of Doctor of Engineering (EngD) Warwick Manufacturing Group, University of Warwick 30 th November 2011 1 Abstract Over the last forty years, the use of electronic controls within the automotive industry has grown considerably. In-vehicle network technologies such as the Controller Area Network (CAN) and Local Interconnect Network (LIN) are used to connect Electronic Control Units (ECU) together, mainly to reduce the amount of wiring that would be required if hardwired integration were used. Modern passenger cars contain many networks, which means that for the architecture designer, there is an almost overwhelming number of choices on how to design/partition the system depending on factors such as cost, weight, availability of ECUs, safety, Electro-Magnetic Compatibility (EMC) etc. Despite the increasing role played by in-vehicle networks in automotive electrical architectures, its design could currently be described as a “black art”. Not only is there an almost overwhelming number of choices facing the designer, but there is currently a lack of a quantifiable process to aid decision making and there is a dearth of published literature available. NetGen is a software tool used to design CAN/J1939, LIN and FlexRay networks. For the product to remain competitive, it is desirable to have novel features over the competition. This report describes a body of work, the aim of which was to research in-vehicle network design processes, and to provide an improvement to such processes. The opportunities of customer projects and availability of customer information resulted in the scope of the research focusing on the adoption of LIN technology and whether the adoption of it could reduce the cost and weight of the target architecture. The research can therefore be seen to address two issues: firstly the general problem of network designers needing to design in-vehicle network based architectures balancing the needs of many design targets such as cost, weight etc, and secondly the commercial motivation to find novel features for the design tool, 2 NetGen. The outcome of the research described in this report was the development of design processes that can be used for the selection of low cost and weight automotive electrical architectures using coarse information, such as that which would be easily available at the very beginning of a vehicle design programme. The key benefit of this is that a number of candidate networked architectures can be easily assessed for their ability to reduce cost and weight of the electrical architecture. 3 Acknowledgements I would like to acknowledge the help from others in the completion of the Engineering Doctorate. I would like to thank my academic supervisors Peter Jones and Ross McMurran and my industrial mentor Paul Faithfull for their helpful comments and guidance throughout the project. Finally I would like to thank my partner Libby Hayward for proof reading final drafts of submissions and this report. Declaration This report is the original work by the author, parts of which have been published elsewhere, as stated in the text. 4 Contents 1. INTRODUCTION ........................................................................................... 13 1.1. The Sponsoring Company – Rapicore ............................................................. 14 1.2. The Product – NetGen ..................................................................................... 15 1.3. Distributed System Development Using NetGen ............................................ 17 1.4. NetGen – Competitor Analysis ........................................................................ 22 1.5. NetGen – Current Sales and Distribution Strategy .......................................... 24 1.6. NetGen – Requirement for Improvement ........................................................ 26 1.7. Aim of Research .............................................................................................. 26 1.8. Flow of Doctorate Submissions ....................................................................... 28 1.9. Flow of this Report .......................................................................................... 32 2. LITERATURE SURVEY ................................................................................ 35 2.1. Trends in Automotive Electronic Systems Integration .................................... 35 2.2. Automotive In-Vehicle Networking Technologies for Control ....................... 39 2.2.1. Controller Area Network Based Technologies ................................................ 39 2.2.2. Local Interconnect Network (LIN) .................................................................. 42 2.2.3. Emergence of High Speed Time Triggered Automotive Control Networks ... 44 2.2.4. Other Emerging Automotive Control Networks .............................................. 50 2.2.5. Multimedia Automotive Networks .................................................................. 52 2.2.6. The Future of Automotive Control Networks .................................................. 54 2.3. Adoption of Control Networks in Other Vehicle Applications ....................... 61 2.4. Processes Used for Designing the Electrical Architecture of Distributed Automotive Control Systems ........................................................................... 63 2.4.1. Design of Network Schedules and Dealing with the Multi-Supplier Problem 64 2.4.2. Designing an Automotive Electrical Architecture to a Target Cost ................ 66 2.5. Which Network Technology is Most Cost Effective? ..................................... 69 3. CAR DOOR SYSTEM LIN BASED HARNESS – CASE STUDY ............... 72 3.1. Case Study Overview ....................................................................................... 72 3.2. Case Study – Main Outcomes .......................................................................... 90 4. PROCESSES FOR ARCHITECTURE SELECTION ..................................... 94 4.1. Architecture Design to Cost Process................................................................ 94 4.2. Architecture Design to Weight Process ......................................................... 101 5. MICROCONTROLLER MEMORY CAPABILITY ASSESSMENT AND VARIANT SELECTION ............................................................................... 105 5.1. ROM and RAM Capability Relationship within a Microcontroller Family .. 106 5.2. Estimation of LIN Communications Stack ROM and RAM Requirements .. 111 5.3. Microcontroller Family ROM/RAM Capability Assessment Process ........... 116 5.4. Microcontroller Variant Selection By ROM/RAM Requirement Estimation 122 6. SPORTSCAR BODY CONTROL ELECTRICAL ARCHITECTURE DESIGN – CASE STUDY ............................................................................ 126 6.1. Case Study – Overview .................................................................................. 126 6.2. Case Study – Main Outcomes ........................................................................ 145 7. CONCLUSION AND RECOMMENDATIONS FOR FURTHER WORK . 147 7.1. Conclusion ..................................................................................................... 147 7.2. Recommendations for Further Work ............................................................. 151 7.2.1. Potential Future Exploitation of Research Findings ...................................... 151 7.2.2. Embedded Software Memory Requirements Modelling ............................... 153 7.2.3. Adaptation of Processes to Other Network Technologies and Applications . 154 7.2.4. Automatic Rule-Based Optimisation of Architecture Design ....................... 154 5 8. REFERENCES .............................................................................................. 155 6 Table of Figures Figure 1 : Example screen shot of the NetGen LIN tool ............................................. 18 Figure 2 : Example LIN schedule screen shot of the NetGen LIN tool ....................... 18 Figure 3 : The NetGen code generation interface ........................................................ 21 Figure 4 : Warwick Control Toolset for ECU development (McLaughlin et al, 2010) ...................................................................................................................................... 24 Figure 5 : Top level process developed during the engineering doctorate .................. 29 Figure 6 : Suggested reading order of the Engineering Doctorate submissions and key outcomes ...................................................................................................................... 31 Figure 7: Stand alone ECUs (No Integration).............................................................. 35 Figure 8: Hard-wired ECU Integration .......................................................................