With ever increasing contents (safety, driver assistance, infotainment, etc.) in today's automotive systems that rely on electronics and software, the supporting architecture is integrated by a complex set of heterogeneous data networks. A modern automobile contains up to 100 ECUs and several heterogeneous communication buses (such as CAN, FlexRay, etc.), exchanging thousands of signals. The automotive Original Equipment Manufacturers (OEMs) and suppliers face a number of challenges such as reliability, safety and cost to incorporate the growing functionalities in vehicles. Additionally, reliability, safety and cost are major concerns for the industry.
One of the important challenges in automotive design is the efficient and reliable transmission of signals over communication networks such as CAN and CAN-FD. With the growing features in automotives, the OEMs already face the challenge of saturation of bus bandwidth hindering the reliability of communication and the inclusion of additional features. In this dissertation, we study the problem of optimization of bandwidth utilization (BU) over CAN-FD networks. Signals are transmitted over the CAN/CAN-FD bus in entities called frames. The signal-to-frame-packing has been studied in the literature and it is compared to the bin packing problem which is known to be NP-hard.
By carefully optimizing signal-to-frame packing, the CAN-FD BU can be reduced. In Chapter 3, we propose a method for offset assignment to signals and show its importance in improving BU. One of our contributions for an industrial setting is a modest improvement in BU of about 2.3%. Even with this modest improvement, the architecture's lifetime could potentially be extended by several product cycles, which may translate to saving millions of dollars for the OEM. Therefore, the optimization of signal-to-frame packing in CAN-FD is the major focus of this dissertation. Another challenge addressed in this dissertation is the reliable mapping of a task model onto a given architecture, such that the end-to-end latency requirements are satisfied. This avoids costly redesign and redevelopment due to system design errors. / Ph. D. / Automobiles today are equipped with a variety of advanced features, such as adaptive cruise control, lane departure warning systems, information and entertainment systems, etc. These advanced features rely on electronics and software. A modern automobile consists of up to 100 computer systems that are interconnected by several buses (in-vehicle communication networks), exchanging thousands of signals (which are data entities such as sensor data, control commands, etc.). The addition of new functionalities means additional complexity and more demand of existing resources such as bus bandwidth. The automotive companies face a number of challenges such as reliability, safety and cost to incorporate the growing features in vehicles with the limited resources. In this dissertation, we study the problem of optimization of bandwidth utilization (BU) over a communication bus used in automotives. In Chapter 3, we show that for an automobile company even a modest improvement in BU of about 2.3% could potentially extend the bus architecture’s lifetime by several product cycles. This may translate to saving millions of dollars for the company. Therefore, the optimization of bandwidth utilization over a communication bus is the major focus of this dissertation. Another problem addressed in this dissertation is the reliable mapping of a software model onto a given architecture (for an automotive system), such that the timing requirements are satisfied. This avoids costly redesign and redevelopment due to system design errors.
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/82839 |
| Date | 16 April 2018 |
| Creators | Joshi, Prachi |
| Contributors | Electrical and Computer Engineering, Zeng, Haibo, Shukla, Sandeep K., Ravi, Sekharipuram Subramaniam, Hsiao, Michael S., Vullikanti, Anil Kumar S., Yang, Yaling |
| Publisher | Virginia Tech |
| Source Sets | Virginia Tech Theses and Dissertation |
| Detected Language | English |
| Type | Dissertation |
| Format | ETD, application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
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