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The hundreds of electronic control devices used in an automotive system can effectively communicate with one another, thanks to an in-vehicle network (IVN) like FlexRay. Even though every node in the network will be running on its local clock, a global notion of time is essential. The clock synchronisation algorithm accomplishes this global time between the nodes in FlexRay. In this era of self-driving cars, the vehicle’s safety is paramount. For the vehicle to operate safely and smoothly, timely communication of information is critical, and the clock synchronisation algorithm plays a vital role in this. It is essential to formally test the clock synchronisation algorithm’s correctness. This paper attempts to model and verify the clock synchronisation algorithm of FlexRay using formal methods, which in turn enhance the reliability of safety-critical automotive systems. The clock synchronisation is modelled as a network of six timed automata in the UPPAAL model checker. Three system models were developed, a model for an ideal clock, another for a drifting clock, and a third model considering propagation delay. The precision of the clocks is verified to be within the prescribed limits. Simulation studies are also conducted on the model to ensure that the clock’s drift is always within the precision. [ABSTRACT FROM AUTHOR]

Today's vehicles have become increasingly complex, as consumers demand more features and better quality in their cars. Most of these new features require additional electronic control units (ECU) and software control, constantly pushing back the limits of existing architectures and design methodologies. Indeed, modern automobiles have a larger number of critical time functions distributed and running simultaneously on each ECU. Data Distribution Service (DDS) is a publish/subscribe middleware specified by the international consortium Object Management Group (OMG), which makes the information available in real time, while offering a rich range of quality of service (QoS) policies. In this paper, we propose a new methodology to integrate DDS in automotive application. We evaluate the performance of our new design by testing the fulfillment of real time QoS requirements. We also compare the performance of the vehicle application when using FlexRay and Ethernet networks. Computations prove that the use of DDS over Gigabit Ethernet (GBE) is promising in the automotive field. [ABSTRACT FROM AUTHOR]

The FlexRay protocol provides deterministic and fault-tolerant communication for automotive applications with stringent requirements regarding reliability and real-time performance. But the lack of intrinsic security mechanisms makes FlexRay vulnerable to spoofing and DoS attacks while existing features are not sufficient to assure reliable communication in the presence of adversaries. Since adding cryptography mandates for secret shared keys, providing secure key establishment techniques is critical in assuring the intended security objectives. In this paper we propose a backward compatible key agreement scheme for FlexRay communication based on intrinsic characteristics of the FlexRay physical layer. In particular, we determine that the symbol window is suitable for implementing a covert channel based on physical properties of the bus which allows us to bootstrap a secure session key between two nodes or to re-enforce existing shared keys. We evaluate and discuss the performance of software-based implementations of the proposed mechanism on two different automotive embedded platforms relying only on the application level. [ABSTRACT FROM AUTHOR]

The Automotive Industry sector and automotive allied firms have grown significantly far above the expectations in recent years, and their expectations from undergraduates/postgraduates are peaking up every moment. The Automotive Industry pioneers such as Bosch, Mercedes, Continental, Delphi, and many more expect industry-ready graduates, so that they can put them on the project directly without spending much time on the OJT's(On Job Training). This would greatly reduce the time to market their products. The automotive industry is looking for skilled engineers having strong hands-on experience in embedded C, Model-Based Design & development, communication protocols like CAN, LIN, Flexray, and exposure to modern industry tools like CANalyzer/Busmaster and VMLAB. To address the industry needs stated above, at an institute level every student undergo automotive electronics theory course along with automotive electronics lab as a part of the curriculum during the sixth semester but this does not completely fill the gap, therefore, an Advanced Automotive Course called as "VAPs" is conducted only for the automotive industry placed students after the completion of the graduate program. The paper details about the VAPs conducted for the automotive industry placed graduates. This course greatly helped the students to crack the post-placement test conducted by the industry, and it also has significantly reduced the training programs conducted in the industry. VAPs indirectly boosted the placement count. [ABSTRACT FROM AUTHOR]

FlexRay offers high-speed reliable transmission in the vehicle domain. Thus, it is one of the most popular in-vehicle communication protocols for the applications that are safety-critical or applications with very low transmission time requirement. Due to the real-time constraint, the worst case end-to-end delay (EED) for such applications transmitting over a shared bus must be known. This paper addresses the problem of computation of EED for a given set of tasks with precedence constraint and corresponding messages, which are scheduled with slot multiplexing for event-triggered communication over the dynamic segment of FlexRay. First, computing precise delay has been shown to be an intractable problem. Subsequently, motivated by the intractability, an efficient estimation technique has been proposed to compute approximate EED. Unlike the common practice of considering the network in isolation, we present a comprehensive timing analysis, which considers the effects of task execution as well. Moreover, EED is allowed to be greater than interactivation time of task graph. The extensive simulation has been performed on the test cases generated with uniform as well as normal distribution. Note to Practitioners—In the past few decades, due to the large-scale use and sophistication of automotive electronic systems, various in-vehicle communication networks and protocols are also evolving. FlexRay is one such in-vehicle communication protocol, which provides the mechanism for the fault-tolerant high-speed communication over FlexRay bus. FlexRay is widely being employed for safety-critical applications in the automotive domain. For such applications, often the timing constraint is imposed with a bound on the worst case EED. Thus, timing properties of the designed network must be verified before applying it on the real domain such that the worst case EED for the propagation of an event at sensor end to actuator end is known. The proposed estimation technique can be used to compute approximate EED for an application scheduled with other applications over the dynamic segment of FlexRay. In addition, various guidelines for designing the network in order to reduce overestimation have also been presented. [ABSTRACT FROM AUTHOR]

In order to improve the bandwidth utilization, this paper researched on optimization of the static segment of FlexRay based on slot multiplexing. It encoded the transmitted signal into a message frame, and transformed the problem into a constrained packing problem. It encapsulated the signal with multiple relationships into a message frame and solved it by BFD algorithm. Based on this, it put forward a method that could maximize the bandwidth and minimize the number of frame ID. Finally, the verification object was the FlexRay chassis synthesis control and safety system. Experimentally, the proposed algorithm increases the bandwidth utilization by 18.7%, reduces the proportion of FID in each communication cycle by 90.47%, and increases the static time slot utilization in the cycle by 41.52%. [ABSTRACT FROM AUTHOR]

We designed a Simulink vehicle blockset in order to integrate safety, reliability, best condition of luxury and comfort in modern models by adding or modifying some old algorithms, implemented as application layer components. The proposed blockset corresponds to the Society of Automotive Engineers benchmark which is normally connected by the CAN bus that we replaced by the FlexRay bus. We used the Embedded MATLAB tool for implementing this blockset in order to generate a portable C standard code. To connect the designed sub-blocks together, we applied the real-time middleware data distribution service (DDS) and the FlexRay protocol. In this paper, we focused our interest on the implementation of the Simulink blockset with its different sub-blocks and we then identified their DDS entities and their QoS profiles. We also calculated the worst-case response time, based on the full scheduling model, which served to configure the DDS deadline QoS and the FlexRay protocol parameters. [ABSTRACT FROM AUTHOR]

Recently, the authors have proposed a scalable holistic scheduling approach for time-triggered applications on FlexRay, under end-to-end deadline and data dependency constraints. This approach divides the problem to two sub-problems that can be solved separately. The first sub-problem optimally schedules the set of messages to minimize number of used slots, and with respect to information exchanges between tasks and messages, end-to-end deadlines and FlexRay protocol constraints. The second sub-problem optimally schedules the set of tasks to minimize tasks response times, with respect to the solution returned by the first sub-problem. In this paper, our goal is to increase the scalability of our solution to each sub-problem. We propose a greedy heuristic approach for the first sub-problem that can find feasible solutions at a low runtime cost. In addition, to resolve assignment conflicts, we apply rescheduling the conflicted application with offset modification and priority promotion procedures. Furthermore, we show that the task scheduling in the second sub-problem can be divided into K independent child sub-problems, where K is the number of ECUs. Our experiments show high scalability and efficiency of our approaches comparing with our optimization-based approaches in the previous work. [ABSTRACT FROM AUTHOR]

Due to properties of flexibility, adaptiveness, error tolerance, and time-determinism performance, the FlexRay communication protocol has been widely used to investigate robot systems and new generation of automobiles. In this paper, with the FlexRay communication protocol, the tracking problem of a class of cyber-physical systems are investigated by developing a general hybrid model, in which an emulation controller is utilized. Based on the proposed hybrid model, some sufficient conditions are established to guarantee the convergence of tracking errors. Then, the maximum allowable transmission interval (MATI) of the static/dynamic segment is obtained with a more general formula than the ones in some the previous works. The obtained MATI over the FlexRay communication network can be adjusted via the appropriate length of the static/dynamic segment, which reflects the flexibility of FlexRay. Finally, the results are verified by considering the tracking problem of a single-link robot arm system as well as the stabilization of a batch reactor system. [ABSTRACT FROM AUTHOR]

The portfolio of models offered by car manufacturing groups often includes many variants (i.e., different car models and their versions). With such diversity in car models, variant management becomes a formidable task. Thus, there is an effort to keep the variants as close as possible. This simple requirement forms a big challenge in the area of communication protocols. When several vehicle variants use the same signal, it is often required to simultaneously schedule such a signal in all vehicle variants. Furthermore, new vehicle variants are designed incrementally in such a way as to maintain backward compatibility with the older vehicles. Backward compatibility of time-triggered schedules reduces expenses relating to testing and fine-tuning of the components that interact with physical environment (e.g., electromagnetic compatibility issues). As this requirement provides for using the same platform, it simplifies signal traceability and diagnostics, across different vehicle variants, besides simplifying the reuse of components and tools. This paper proposes an efficient and robust heuristic algorithm, which creates the schedules for internal communication of new vehicle variants. The algorithm provides for variant management by ensuring compatibility among the new variants, besides preserving backward compatibility with the preceding vehicle variants. The proposed method can save about 20% of the bandwidth with respect to the schedule common to all variants. Based on the results of the proposed algorithm, the impact of maintaining compatibility among new variants and of preserving backward compatibility with the preceding variants on the scheduling procedure is examined and discussed. Thanks to the execution time of the algorithm, which is less than one second, the network parameters like the frame length and cycle duration are explored to find their best choice concerning the schedule feasibility. Finally, the algorithm is tested on benchmark sets. [ABSTRACT FROM AUTHOR]

On-board data exchange systems evolve with the development of vehicles. These are specialized constructions created from scratch to meet the specific tasks of modern control systems. The article presents the basic milestones in the evolution of telecommunications buses in vehicles from the beginning of their creation to the present day with the identification of areas that are the starting point in new directions of their development. [ABSTRACT FROM AUTHOR]

Recently, FlexRay was developed to replace the controller area network (CAN) protocol in the chassis network systems to provide high-speed data transmission as well as hardware redundancy for safety. However, FlexRay network design is more complicated than with CAN protocol, which has been an in-vehicle network (IVN) standard for car manufacturers for decades, because the FlexRay has many parameters such as the base cycle or slot lengths. To simplify the FlexRay network design and assist vehicle network designers in configuring a FlexRay network, this paper presents an automatic field bus exchange format (FIBEX) generation method for migration from the CAN message description format such as the DBC format to the FlexRay FIBEX format. The automatic FIBEX generation method is examined by simulating a chassis networking system using a DBC benchmark tool, which demonstrates the feasibility of the system and the reduction in workload for network designers. [ABSTRACT FROM AUTHOR]

One of the most dynamic industries nowadays is the automotive industry. It has dramatically changed from safe, comfortable, and equipped with many entertainment systems to connected autonomous vehicles during the last decade. Although the "Connected Autonomous vehicles" trend dramatically influences the economy, it increases automation and connectivity. Consequently, vehicles can be considered an Internet of Things (IoT) network. Accordingly, the cyberattack surface is more significant, with many vulnerabilities. Considering the fundamental security weakness of automotive onboard networks, besides their superimposing, we firmly believe that a unified security solution is required to resolve the current automotive security problem. This paper proposes an automotive security solution called Generic Automotive Security Suit (GASS). (GASS) is designed to be a practical security solution deployed in the complicated automotive environment. In addition, it defines a standard secure inter-communication between onboard networks. We also introduce the Lightweight Generic Authentication Protocol (LXAP) as the building block of the GASS. We address different security scenarios which face the industry nowadays. The new proposed system does not affect the complexity level of the automotive network. In addition, our simulation results have shown that the LXAP enables security preservation over vehicles' complex networks. [Display omitted] [ABSTRACT FROM AUTHOR]

Due to the development of the Internet of Vehicles (IoV) and advanced driver-assistance systems (ADAS), the Ethernet has become one of the most important communication protocols for the future of automotive networks. This is because the existing communication protocols (such as FlexRay) do not provide sufficiently high bandwidth requirements. The main challenge for the automotive industry will be to transfer and extend standard IP and Ethernet into vehicles and still fulfill the automotive requirements. The automotive gateway not only links two or more protocols and exchanges the data using each, but also monitors and ensures functional safety. This paper proposes a FlexRay/Ethernet gateway by considering the development conditions of embedded systems and the security in the field of vehicle networking. The proposed method is implemented on the Field Programmable Gate Array (FPGA) system to evaluate running time and to analyze the overhead of the security mechanism. For one-to-one mapping logic, the execution times of FlexRay to the Ethernet path and Ethernet to FlexRay path are constant, at 4.67 μs and 6.71 μs, respectively. In particular, cybersecurity can be integrated as an extension of the gateway with low latency and power consumption.

FlexRay is becoming the in-vehicle communication network of the next generation. In this study, the main contents are the FlexRay network static segment scheduling algorithm and optimization strategy, improve the scheduling efficiency of vehicle network and optimize the performance of communication network. The FlexRay static segment characteristic was first analyzed, then selected bandwidth utilization as the performance metrics to scheduling problem. A signal packing method is proposed based on Next Fit Decreasing (NFD) algorithm. Then Frame ID (FID) multiplexing method was used to minimize the number of FIDs. Finally, experimental simulation by CANoe. FlexRay software, that shows the model can quickly obtain the message schedule of each node, effectively control the message payload size and reduced bus payload by 16.3%, the number of FID drops 53.8% while improving bandwidth utilization by 32.8%. [ABSTRACT FROM AUTHOR]

Modern vehicles employ a large amount of distributed computation and require the underlying communication scheme to provide high bandwidth and low latency. Existing communication protocols like Controller Area Network (CAN) and FlexRay do not provide the required bandwidth, paving the way for adoption of Ethernet as the next generation network backbone for in-vehicle systems. Ethernet would co-exist with safety-critical communication on legacy networks, providing a scalable platform for evolving vehicular systems. This requires a high-performance network gateway that can simultaneously handle high bandwidth, low latency, and isolation; features that are not achievable with traditional processor based gateway implementations. We present VEGa, a configurable vehicular Ethernet gateway architecture utilising a hybrid FPGA to closely couple software control on a processor with dedicated switching circuit on the reconfigurable fabric. The fabric implements isolated interface ports and an accelerated routing mechanism, which can be controlled and monitored from software. Further, reconfigurability enables the switching behaviour to be altered at run-time under software control, while the configurable architecture allows easy adaptation to different vehicular architectures using high-level parameter settings. We demonstrate the architecture on the Xilinx Zynq platform and evaluate the bandwidth, latency, and isolation using extensive tests in hardware. [ABSTRACT FROM AUTHOR]