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The FlexRay bus is a modern standard used in the automotive industry. It offers deterministic message transmission with zero jitter while using time-triggered scheduling in the static segment. When several vehicle variants (i.e. different models and their versions) share the same signal, the car manufacturers require to schedule such signal at the same time in all vehicle variants. This requirement simplifies the signal traceability and diagnostics in different vehicle variants using the same platform and simplifies reuse of components and tools. In this paper, we propose a first fit based heuristic algorithm which creates the schedules for several vehicle variants at once, while transmitting a given signal at the same time in all the schedules. The scheduling algorithm also takes the time constraints as release dates and deadlines into account. Finally, different algorithm versions are compared on benchmark sets and low computational time demands are validated on large instances.

Sensors and actuators are the core components of all mechatronic systems used in a broad range of diverse applications. A relatively new and rapidly evolving area is the one of rehabilitation and assistive devices that comes to support and improve the quality of human life. Novel exoskeletons have to address many functional and cost-sensitive issues such as safety, adaptability, customization, modularity, scalability, and maintenance. Therefore, a smart variable stiffness actuator was developed. The described approach was to integrate in one modular unit a compliant actuator with all sensors and electronics required for real-time communications and control. This paper also introduces a new method to estimate and control the actuator's torques without using dedicated expensive torque sensors in conditions where the actuator's torsional stiffness can be adjusted by the user. A 6-degrees-of-freedom exoskeleton was assembled and tested using the technology described in this paper, and is introduced as a real-life case study for the mechatronic design, modularity, and integration of the proposed smart actuators, suitable for human–robot interaction. The advantages are discussed together with possible improvements and the possibility of extending the presented technology to other areas of mechatronics.

Modern in-vehicle networks are comprised of heterogeneous systems that use various communication protocols with different source clocks. Moreover, gateway systems are designed with additional features that ensure converted/forwarded data meet real-time constraints. In this paper, we propose a synchronization mechanism for FlexRay and Ethernet audio video bridging (AVB) network that guarantees a high quality-of-service. We also designed the corresponding embedded system based-gateway system. Moreover, we built an in-vehicle network environment that consists of FlexRay and Ethernet AVB networks using an embedded system, which is integrated and synchronized by the gateway. We evaluate the synchronization performance of the proposed method using the developed gateway by conducting experiments as well as a theoretical analysis. The results of the experiment show that the synchronization mechanism provides timing guarantees for the FlexRay network that are similar to those of the Ethernet AVB network.

Network operation of FlexRay Electronic Control Unit (ECU) in passenger cars is influenced by the significant number of parameters that have to be written into the ECU FlexRay controller. To keep the FlexRay network robust, the correct parameter values must be set in all ECUs of the FlexRay communication cluster. This is not a trivial task since particular ECUs are supplied by different manufacturers and any manufacturer can change some parameter either by mistake or even intentionally. The effect of such a change is generally unpredictable and can often be observed under specific operational conditions only. The most serious effect is a global FlexRay network failure, which usually leads to the fatal vehicle malfunction. Hence it was necessary to develop, implement and validate new dedicated measurement methods, enabling the evaluation of actual values of the most critical FlexRay parameters at the Open Systems Interconnection (OSI) data-link layer and thus the ECUs individual acceptances testing for system integrator verification purposes. As the mass production of FlexRay controllers is not applicable due to a lack of test specific features, deployment of these methods is enabled by utilization of unique FPGA-based FlexRay controller implementation. Proposed measurement methods are focused on parameters specifying the FlexRay wakeup protocol, FlexRay startup procedure, and the FlexRay synchronization mechanism. Each measurement method is described in detail, including its limits and prerequisites. All the developed methods were validated by experiments on real FlexRay networks and results are included in the paper. Two different types of FlexRay controller core (Freescale and Bosch E-Ray) were used in ECU under test (EUT) to eliminate the risk of measurement method dependence on a specific controller implementation.

FlexRay is a hybrid communication protocol tailored to the requirements in the automotive domain, supporting both time-triggered and event-triggered communication with high data-rates. The time-triggered static segment is commonly used for in-vehicle communication while the event-triggered dynamic segment is used for diagnostics and configuration. This paper addresses the problem of synthesizing schedules for the static FlexRay segment for asynchronous scheduling, following the design approach of current automotive architectures. Previous approaches largely focused on FlexRay 2.1 while the few existing approaches for FlexRay 3.0 are nonoptimal in several aspects. As a remedy, our framework makes use of all new features of version 3.0 while supporting the still predominantly used FlexRay 2.1, making it backward compatible. The following approaches are proposed: 1) a single-stage integer linear programming (ILP) approach that determines an optimal solution but does not scale; 2) a multistage ILP for combining previously generated subsystem schedules to a global schedule. It clearly improves the scalability but is not optimal. The multistage approach allows to integrate and convert existing FlexRay 2.1 schedules into a FlexRay 3.0 schedule which is important for legacy reasons, i.e., to reduce testing and certification efforts; 3) a greedy heuristic which scales well and obtains high quality solutions in comparison with the optimal solution, but is unsuitable to integrate existing schedules; and 4) metaheuristic approaches based on genetic algorithms or simulated annealing to evaluate the benefits of the proposed approaches.

The FlexRay bus is a communication standard used in the automotive industry. It offers a deterministic message transmission in the static segment following a time-triggered schedule. Even if its bandwidth is ten times higher than the bandwidth of controller area network (CAN), its throughput limits are going to be reached in high-class car models soon. A solution that could postpone this problem is to use an efficient scheduling algorithm that exploits both channels of the FlexRay. The significant and often neglected feature that can theoretically double the bandwidth is the possibility to use two independent communication channels that can intercommunicate through the gateway. In this paper, we propose a heuristic algorithm that decomposes the scheduling problem to the electronic control unit (ECU)-to-channel assignment subproblem, which decides which channel the ECUs should be connected to and the channel scheduling subproblem that creates static segment communication schedules for both channels. The algorithm is able to create a schedule for cases where channels are configured in the independent mode, as well as in the fault-tolerant mode or in cases where just part of the signals are fault tolerant. Finally, the algorithm is evaluated on real data and synthesized data, and the relation between the portion of fault-tolerant signals and the number of allocated slots is presented.

In this paper, we propose vehicle SoC fault diagnosis platform using FlexRay protocol in order to detect the faults of semiconductor control chip even after vehicle production. Before FlexRay protocol by sending NFI (Null Frame Indicator) bit among the header segment and a specific identifier in the payload segment of FlexRay frame, this technique can be distinguishable from normal mode and test mode. By using this technique, it is possible to detect the faults such as performance degradation of vehicle network system caused by the aging or several problems of vehicle semiconductor chip. Also high reliability and safety of vehicle can be maintained by using structural test for vehicle SoC fault detection.

Time-Triggered Communication helps readers build an understanding of the conceptual foundation, operation, and application of time-triggered communication, which is widely used for embedded systems in a diverse range of industries. This book assembles contributions from experts that examine the differences and commonalities of the most significant protocols including: TTP, FlexRay, TTEthernet, SAFEbus, TTCAN, and LIN. Covering the spectrum, from low-cost time-triggered fieldbus networks to ultra-reliable time-triggered networks used for safety-critical applications, the authors illustrate the inherent benefits of time-triggered communication in terms of predictability, complexity management, fault-tolerance, and analytical dependability modeling, which are key aspects of safety-critical systems. Examples covered include FlexRay in cars, TTP in railway and avionic systems, and TTEthernet in aerospace applications. Illustrating key concepts based on real-world industrial applications, this book: Details the underlying concepts and principles of time-triggered communication Explores the properties of a time-triggered communication system, contrasting its strengths and weaknesses Focuses on the core algorithms applied in many systems, including those used for clock synchronization, startup, membership, and fault isolation Describes the protocols that incorporate presented algorithms Covers tooling requirements and solutions for system integration, including scheduling The information in this book will be extremely useful to industry leaders who design and manufacture products with distributed embedded systems based on time-triggered communication. It will also benefit suppliers of embedded components or development tools used in this area. As an educational tool, this material can be used to teach students and working professionals in areas including embedded systems, computer networks, system architectures, dependability, real-time systems, and automotive, avionics, and industrial control systems.

This paper introduces a simulation-based approach for design and test of application software for timetriggered communication systems. The approach is based on the SIDERA simulation system that supports the time-triggered real-time protocols TTP and FlexRay. We present a software development platform for FlexRay based communication systems that provides an implementation of the AUTOSAR standard interface for communication between host application and FlexRay communication controllers. For validation, we present an application example in the course of which SIDERA has been deployed for development and test of software modules for an automotive project in the field of driving dynamics control.

FlexRay bus is considered as a more promising bus in the future with the performance of real-time, scalable, and fault-tolerant. In this paper we will design an electric vehicle battery management system (BMS) based on FlexRay bus, including the hardware design, the SoC estimation method, FlexRay protocol design and software development. The test bench experiment results show the system design is reasonable and feasible.Keywords- FlexRay, BMS, Li-ion battery,SoC, Design

Part I of this paper proposed a development process and a system platform for the development of autonomous cars based on a distributed system architecture. The proposed development methodology enabled the design and development of an autonomous car with benefits such as a reduction in computational complexity, fault-tolerant characteristics, and system modularity. In this paper (Part II), a case study of the proposed development methodology is addressed by showing the implementation process of an autonomous driving system. In order to describe the implementation process intuitively, core autonomous driving algorithms (localization, perception, planning, vehicle control, and system management) are briefly introduced and applied to the implementation of an autonomous driving system. We are able to examine the advantages of a distributed system architecture and the proposed development process by conducting a case study on the autonomous system implementation. The validity of the proposed methodology is proved through the autonomous car A1 that won the 2012 Autonomous Vehicle Competition in Korea with all missions completed.

In this paper, a 60 V tolerance transceiver with ESD (electrostatic discharge) protection is proposed for FlexRay-based communication systems. The FlexRay transceiver comprises three protective devices, including an over-voltage detector, high-voltage ESD devices, and high-voltage diodes. The over-voltage detector is in charge of detecting bus (BP and BM) status to distinguish whether any hazard has happened. If the over-voltage detector is activated, the FlexRay transceiver must be turned off for safety. The high-voltage ESD device uses a base-floating PNP serving as a bi-directional device. Besides, it can protect the FlexRay transceiver whenever it is short-circuited in positive or negative high voltages. Notably, the high-voltage diode will eliminate the negative leakage current when negative high voltage hazards appear in FlexRay channels. An experimental prototype is implemented using a 0.18 μm CMOS mixed-signal based generation II HV BCD process. The measurement results justify the functional correctness and 60 V tolerance of the proposed FlexRay transceiver design.

X-by-Wire system is a typical automotive network control system. The control of x-by-wire system depends on communication network (like CAN, TTCAN or FlexRay), it must meet not only the control performance, but also the real-time performance and reliability requirement. Network optimization in x-by-wire system is great significant for achieving these targets. In this paper, first task graph was designed for the x-by-wire system, and different control links were distinguished from the task graph. Then the network optimization algorithm was designed to implement message slot arrangement coordinated with task execution time in the control links, and the principle of the network optimization algorithm design is reducing the control link response time for the best effort. Through a typical car x-by-wire control system, we can see that the network optimization algorithm research has important guidance for the optimization of the system message transmission, and can improve the system's real-time performance.

An autonomous car is a self-driving vehicle that has the capability to perceive the surrounding environment and navigate itself without human intervention. For autonomous driving, complex autonomous driving algorithms, including perception, localization, planning, and control, are required with many heterogeneous sensors, actuators, and computers. To manage the complexity of the driving algorithms and the heterogeneity of the system components, this paper applies distributed system architecture to the autonomous driving system, and proposes a development process and a system platform for the distributed system of an autonomous car. The development process provides the guidelines to design and develop the distributed system of an autonomous vehicle. For the heterogeneous computing system of the distributed system, a system platform is presented, which provides a common development environment by minimizing the dependence between the software and the computing hardware. A time-triggered network protocol, FlexRay, is applied as the main network of the software platform to improve the network bandwidth, fault tolerance, and system performance. Part II of this paper will provide the evaluation of the development process and system platform by using an autonomous car, which has the ability to drive in an urban area.

For an Unmanned Aerial Vehicle (UAV) performing a mission, any failure of the flight control system can result in fatal disaster. Therefore, reliability requirement for UAV flight control system becomes increasingly important and then the redundancy technology is considered as a solution to enhance system reliability. This paper studies the designs of reliability, system architecture, and redundancy management logic for UAV flight control system. Therefore, a reliable federated architecture design for triple redundant UAV flight control system is introduced, in which the distributed hardware design combined with centralized software framework was adopted as well. The number of subsystems in the case study is more than that of centralized architecture and less for distributed architecture. Next, the fault detection and fault tolerant design can be achieved, and simultaneously the design problems associated with distributed software framework was reduced. Furthermore, by using the distributed hardware, system's reliability requirement of single hardware module was decreased. Consequently, the goal of high reliability for the entire system reached. Finally, FlexRay bus with time-trigger mechanism was chosen to simulate the communication of such a federated architecture designed. The experimental results show that the design is reasonable and satisfy the high reliability, high performance-price ratio and high expandability requirements of UAV flight control system.

International audience; We design state observers for nonlinear networked control systems (NCS) implemented over FlexRay. FlexRay is a communication protocol used in the automotive industry, which has the feature to switch between two scheduling rules during its communication cycles. These switches induce technical difficulties when modeling, designing and analysing observers for such systems compared to standard NCS. We present a solution based on the emulation approach. Given an observer in the absence of communication constraints, we implement it over the network and we provide sufficient conditions on the latter, to preserve the stability property of the observer. In particular, we provide explicit bounds on the maximal allowable transmission intervals , which adapt to the lengths of the segment associated to each scheduling rule. We assume that the plant dynamics and measurements are affected by noise and we guarantee an input-to-state stability property for the corresponding estimation error system. The overall system is modeled as a hybrid system and the analysis relies on the use of a novel hybrid Lyapunov function.

Flight control computer is very important for flight safety, while redundant flight control system can greatly enhance flight safety. In this paper, based on the existing flight control computer hardware architecture and comprehensive comparison of various types of buses, FlexRay bus is selected for data interaction. Through statistical analysis on the upstream and downstream data in the bus, treble-redundancy flight control computer system based on FlexRay bus is designed, in which data transmission is strictly in accordance with defined time slice. Finally, Semi-physical simulations are conducted. By comparing the output attitude angles and rudder values of three groups of UAVs, the results demonstrate the reliability of FlexRay bus and also illustrate that the designed treble-redundant fault-tolerant flight control computer based on FlexRay bus technology can improve the safety and reliability of UAV.

FlexRay protocol has been developed as the de-facto industry standard for next generation in-vehicle communication with high bandwidth, time-triggered architecture and dual-channel redundancy. However, it does not define a mechanism to handle the transient errors, which is frequent on the common-used twisted wire cable. Thereby, FlexRay is hindered for the application in safety-critical communications. This paper presents a detailed Prompt ReTransmission Mechanism (PRTM) with acknowledgement and retransmission scheme to recovery the transient errors in the more safety-critical time-triggered messages. Considering the feasibility, failure probability reduction and bandwidth optimization, the amount of error messages permitted to be retransmitted in one cycle and the number of acknowledgement transmission is important for failure probability reduction; the schedule of the messages for acknowledgement and retransmission should be studied to optimize the bandwidth utilization. An example is used for demonstrating the effectiveness of PRTM, which can not only greatly reduce the messages failure probability but accomplish the retransmission within one cycle, together with an extra design cost and a small bandwidth waste. With PRTM, FlexRay would be notably promoted in safety-critical applications.

Increasingly more software-based applications are being developed and deployed in modern vehicles. As a result, the extensibility of a system design has become an important issue in order to accommodate more future applications and update of existing ones on one hand and reduce the effort and cost of re-design, test and validation on the other. In this paper, we discuss the extensibility-driven design in the automotive E/E architecture. We explain the motivation for such a design objective and discuss the definition of extensibility metric and extensibility-driven design methods under two different setting, namely the system based on CAN bus and FlexRay bus. Based on these two examples, we illustrate the importance and advantages of extensibility-driven design in the automotive E/E architecture.

Flexibility, determinism, fault-tolerance and high-speed are features that make FlexRay networks one of the newest x-by wire communication systems. It offers reliable and real-time capable high-speed data transmission between components. In the same context, the real-time middleware, Data Distribution Service (DDS) is an appropriate alternative for the standard vehicular middleware. In the present paper, we have implemented a vehicle Simulink Blockset model, precisely the chassis domain. The proposed blockset corresponds to the Society of Automotive Engineers SAE benchmark model connected by the FlexRay Bus. We have chosen the Embedded Matlab tool for implementing this blockset. It permits us to generate C code for different blocks in order to validate the vehicle system design. In this paper, we have focused our interest on the Blockset Simulink implementation of the Active Frame Steering and Electronic Brake Control models. Then we have identified the DDS Data Readers and Data Writers adapted to this Blockset using the FlexRay Network.

Intelligent robots commonly adopt Network-Based Control Systems (NBCS). For control of a robot hand or a robot head, many sensor data and control commands need to be transmitted in real time, so they have necessitated communication systems with high transmission capability. Traditionally, CAN is widely used for intelligent robots, but it presents bandwidths that are too low for the control of a high performance system. In this paper, the relation between the transmission period and the performance of a multi-motor control system is analyzed, and a multi-motor control system for a human robot hand is implemented based on the FlexRay communication system, which is an emerging in-vehicle communication network system. FlexRay parameter optimization for a robot system is studied, and a real position control test is conducted, to validate the implemented system.

As vehicles become more intelligent, in-vehicle networking (IVN) systems such as controller area network (CAN) are essential for the convenience and safety of drivers. To expand the applicability of IVN systems, attention is currently being focused on chassis networking systems that require increased network capacity and real-time capabilities. FlexRay was developed to replace CAN protocol in chassis networking systems, to remedy the shortage of transmission capacity and unsatisfactory real-time transmission delay of conventional CAN. However, FlexRay network systems require a complex scheduling method, which is a barrier to their implementation as chassis networking systems. In particular, if we want to migrate from a CAN network to a FlexRay network using the well-defined CAN message database, which has been specifically constructed for chassis networking systems by automotive vendors, a new type of scheduling method is necessary to reduce scheduling efforts during the software development process. This paper presents a node-based scheduling method for easy migration from a CAN network to a FlexRay network system. To demonstrate the feasibility of the technique, its performance is evaluated in terms of various software complexity indices.

Nowadays, communication protocols are used in safety-critical automotive applications. Among the communication protocols, FlexRay, with real-time and reliable characters, is expected to become the communication backbone for future automotive systems. Therefore, a DC motor speed control system based on FlexRay network is presented in this paper to verify these characters. The following works have been done in this paper: study the FlexRay protocol specification, design the structure, programming, analyze the test results to get transmission delay time. Using the test system, FlexRay network was verified that message can be transferred quickly and correctly.

Spatially distributed systems which share communication resources have advantages such as lower implementation cost, better flexibility and reliability. When real-time distributed control applications make use of such architecture, the drawbacks are the networked-induced effects, which may severely degrade the controlled system performance. Efforts have been made by both communication and control communities to assess this problem: new control design techniques now consider explicitly the effects of these constraints, and some new communication protocols offer services to support the requirements from this kind of application. FlexRay is a protocol developed to support real-time safety-critical applications. In this study, a FlexRay network is built and an active suspension control is implemented in a distributed environment. The main goal is to analyse the impact the network-induced effects may bring to system performance.

Today, most of the innovation in the automotive domain is in the areas of electronics and software. Modern cars have already been transformed, from largely mechanical entities, to complex embedded systems running on four wheels. High-end cars currently have around 100 electronic control units (ECUs), each with one or more, possibly multicore, processors. These ECUs communicate using different communication buses such as CAN, FlexRay, LIN, and more recently also Ethernet, and are connected to various cameras, radars, ultrasonic sensors, and also to a host of actuators. Such architectures are used to run several millions of lines of software code spanning across safety-critical, driver assistance, comfort, and entertainment related applications.

This paper shows how the performance of an ESC(Electronic Stability Control) system can be affected by the selection of in-vehicle network protocols such as CAN or FlexRay. The vehicle control performance under ESC operation is analyzed by EILS(ECU-In-the-Loop Simulation). The experimental set-up for the EILS of the ESC system consists of two 32-bit microcontroller boards communicated with CAN or FlexRay protocols. A 7-DOF vehicle model and an ESC algorithm with 2-DOF reference vehicle model are implemented on each microcontroller respectively. It is shown by experimental results that the ESC system using the FlexRay protocol can achieve better performance than that using the CAN protocol for a fast and accurate lane changing.

The FlexRay protocol has emerged as the de facto standard for automotive communication systems, and it offers the advantages of both the event-triggered and time-triggered paradigms. To minimize bandwidth consumption (BC) in the static segment of the FlexRay communication cycle, we propose a frame-packing algorithm called BC minimizing with various periodic signals (BCMVPS), which is formulated as generalized integer linear programming that allows the packing of signals with different periods into a message frame. We also present the lower and upper bounds of the size of a static slot, as well as present a heuristic called BC best fit decreasing for linear frame selection for reducing the computing time of the BCMVPS algorithm. We compare the performance of the proposed algorithms with existing algorithms using the Society of Automotive Engineers benchmark data and GNU linear programming kit. The experimental results show that the BC of the proposed algorithms is less than that of the existing frame-packing algorithms.

Network Designer, which is suitable for the CAN, LIN and FlexRay design, is used to design the database of FlexRay according to the actual requirements, including the definition of nodes, messages and signals of FlexRay cluster and the design of communication schedule. And The Network Designer is able to export FIBEX. Import the database file which was well designed to the FlexRay Configuration Tool, then configurate the corresponding parameters of the software and combine it with MATLAB/Simulink to create RTIFlexRayConfig model. MicroAutoBox which is a tool of rapid control prototyping and Simulator which is a tool of hardwarein-the-loop simulation are used as two nodes of FlexRay to verify network performance by transmitting drivers input signals.

The In-Vehicle Network System is a main channel to transmit electronic signals among each automotive node. In order to share the node information from both of chassis and body networks in automobiles, the gateway system is used to realize the communication between CAN and FlexRay systems. In this paper, a modified gateway system based on the node mapping method, the node slotting method, and the corresponding operation algorithm will be proposed. Through the modified gateway system, repeated remodifying problems are solved that is changes of information or ID during transmitting information between CAN and FlexRay systems. Additionally, improvements in the reliability and the amalgamation of the In-Vehicle Network System are shown in this paper.

The transient effect of electromagnetic interference (EMI) produced by electronic equipments has been extensively studied. However, for the electric vehicles, speed changing also introduces considerable amount of interference. In this paper, we study the EMI influences, which include the interferences caused by the electronic switch and the vehicular engine, on the electric vehicular communications systems. The transmission quality of various standards is investigated, including FlexRay, and Control Area Network (CAN).

This paper mainly introduces FlexRay, a high speed, real-time and high reliability bus technology, and researches network topology structure and network communication protocol of FlexRay bus. Then this paper points out that the premise of analyzing FlexRay protocol is catching the bus data transmission, and designs a data acquisition and analysis system with FreeMASTER software and Tektronix TDS3012B digital phosphor oscilloscope. In order to verify the accuracy of the software FlexRay interface design, this paper also describes the analysis and verification procedure of the timing sequence of FlexRay bus. Lastly, this paper reminds of the application prospect of this system.

As vehicles become more intelligent for safety and convenience of drivers, in-vehicle networking systems such as controller are network (CAN) have been widely used due to increasing number of electronic control unit (ECU). Recently, FlexRay was developed to replace CAN protocol in chassis networking systems, to remedy the shortage of transmission capacity and unsatisfactory real-time transmission delay of conventional CAN. However, it is difficult for vehicle network designers to calculate platform configuration registers (PCR) and determine a base cycle or slot length of FlexRay. To assist vehicle network designers for designing FlexRay cluster, this paper presents automatic field bus exchange format (FIBEX) generation algorithm from CANdb information, which is de-facto standard database format for CAN. To design this program, structures of FIBEX, CANdb and relationship among PCR variables are analyzed.

This paper presents a FlexRay Transceiver (FRT) used in an in-vehicle network compliant with FlexRay physical layer standards. FlexRay is a new standard for data/signal communication among ECUs (electronic control unit) installed in a vehicle. FRT at least comprises two major blocks in the physical layer design: the data transmission block, i.e., Bus Driver (BD), which is used to generate signals on the bus and recognize the signal electrical characteristics on the bus; and the control block, i.e., Major Controller, which is in charge of data path, security, and safety. The proposed FRT design in this work is implemented using a typical [email protected] CMOS process. The total core area is 1.01x0.894mm^2 and the power consumption is 76.62mW at a 80MHz system clock.

This paper researches the FlexRay bus main features, communication mechanism and topological structure, and then applies the FlexRay bus to all-electronic computer interlocking system communication network structure. Considering the fail-safe principle ,The paper studies the node design and bus configuration based on all-electronic execution units core , It realizes safe and reliable data communication between the all-electronic execution units and the interlocking machine, the maintenance monitoring machine. At last with real-time comparision between the FlexRay bus and the CAN bus in all-electronic computer interlocking system. it indicates that the FlexRay bus meets the data communication requirements in the computer interlocking system.

Based on the issue of the communication between two FlexRay nodes, this paper proposes a new design straight by illustrating the mechanism with respect to the way of performing it by both hardware and software means. The important part of the mechanism is demonstrated in detail. The experiments through two Electronic Control Units (ECUs) show that the design can realize the communication between two FlexRay nodes well.

Till nowadays, the Controller Area Network (CAN) has been a de facto standard for communication in automotive applications. To meet the requirements of new high-end vehicular systems, new communication protocols such as the FlexRay Communication System and the CAN with Flexible Data-rate (CAN-FD) has been developed. In the near future, it is expected the coexistence of those protocols in the same vehicle, with electronic control units (ECUs) connected to different network buses exchanging information through gateways. In this paper we investigate the following problem: “how to schedule the communication in a vehicular system, considering that a message is transmitted through a network that is composed of CAN-FD, FlexRay and CAN segments interconnected by gateways.” We propose a method for the schedulability analysis of such systems, focusing on the case where a message is generated in a ECU connected to a CAN-FD segment is used by an ECU connected to a CAN bus.

Autonomous power system (APS) that exploits local renewable energy sources has potential to provide useful energy at lower costs when compared with conventional energy. Modern APS involves the control of renewable energy systems with intermittent power production; interaction with conventional energy generation; and management of energy storage and consumption. The system configuration of an APS is often complex due to the mix of energy generations and desire to optimize the utilization of the renewable energy. The fact that a large amount of data must be processed within a very short period of time makes the APS very challenging. In this paper, we introduce a modeling and simulation methodology to analyze autonomous power systems. We develop a simulation platform using VisualSim software package to create simulation programs. We model an APS for hybrid electrical vehicle (HEV) with solar energy, thermoelectricity, and conventional fuel energy using various communication mediums. Simulation results for solar panels are comparable with real results from a solar plant. The proposed simulation platform is easy and reliable to assess the components required in modern APSs. Regarding communication mediums, simulation results suggest that controller area network (CAN) bus outperforms FlexRay and Bluetooth.

Automotive communication systems are complex distributed systems. The design of the electrical physical layer (EPL) is a challenging task. Many parameters affect the signal integrity on the analog bus and the combination of parameter variations can lead to effects (e.g., signal reflections) which degrade the signal and compromise the system reliability. Model-based simulations have been widely proposed as the solution for the design, testing and verification of FlexRay networks. This paper proposes a model-based framework for the design and evaluation of FlexRay communication systems. The framework includes the development of FlexRay system components, the design of different network topologies and the simulation and analysis of EPL. The proposed framework has been developed and possible applications have been figured out. Furthermore, the validation of the proposed approach has been addressed. The validation focuses on the accuracy of the simulations in representing the analog signal on the bus, as well as the accuracy in representing the network timing characteristics. The validation exhaustively explores the system design space, achieving a rigorous analysis of the approach reliability: simulations of 40 different network topologies and 1,264 frames have been evaluated, by comparing simulation results with hardware measurements. The results demonstrate that the proposed framework accurately represents the hardware behavior, and it can be an useful toll during the design and early verification of FlexRay communication networks. Due to the lack of a formal validation approach for the validation of the electrical physical layer, the validation is valuable for the FlexRay community.

Network node designs of hardware system and software system based on in-vehicle FlexRay Bus were put forward. Structure and theory of node’s MCU, communication controller and Bus drive were analyzed. The simplest system of FlexRay Bus node was structured, and main files program, clock program, interruption program, and FlexRay Bus communication program were configured. The operation status of FlexRay Bus protocol was analyzed, and programs of receiving and transmitting data were designed. The experimental system based on MC9S12XF512 was established, and in development environment of CodeWarrior IDE, FlexRay Bus networks nodes communication was accomplished based on TDMA and FTDMA mechanism.

The domain of networked control systems (NCS) has traditionally been concerned with modeling and designing distributed controllers in the presence of control message loss, varying delay and jitter. Here, the characteristics of the network are assumed to be given and the focus has largely been on the controller. While this is meaningful in the context of control over wireless networks, where the network is assumed to be predesigned, in many other domains there is considerable flexibility in designing the network itself. For example, in an automotive architecture, distributed controllers are implemented on multiple electronic control units (ECUs) that communicate over CAN or FlexRay buses. The network design problem in this case consists of mapping control tasks to ECUs, and determining both the scheduling parameters for the ECUs as well as those for the communication buses. Given a choice of these parameters, the controller design problem is similar to that studied in NCS, i.e., that of designing/analyzing the controller. However, the joint design and optimization of the network and the controller gives rise to new research questions, that have neither been studied within the NCS, nor within the embedded systems domain. We refer to such systems as arbitrated networked control systems (ANCS) to emphasize the fact that the arbitration policy in the network also needs to be determined, and discuss recent results that have been obtained in the literature in this context.

In this paper we present an approach to timing analysis of applications communicating over a FlexRay bus, taking into consideration the specific aspects of the publish subscribe paradigm. We give an overview of works dealing with Data Distribution Service (DDS), scheduling over FlexRay and scheduling over the Control area Network (CAN). We are interesting in real time Quality of Service (QoS) for DDS. We specially focus on real time communication on static and dynamic FlexRay bus. We give our approach to calculate deadline on a DDS distribution using the equal Flexibility. We give also DDS and the task models for the computation.

Recently, FlexRay was developed to replace controller area network (CAN) protocol in chassis networking systems, to remedy the shortage of transmission capacity and unsatisfactory real-time transmission delay of conventional CAN. FlexRay network systems require correct synchronization and complex scheduling parameters. However, because platform configuration register (PCR) setting and message scheduling is complex and bothersome task, FlexRay is more difficult to implement in applications than CAN protocol. To assist a network designer for implementing FlexRay cluster, this paper presents an analysis of FlexRay platform configuration register and automatic generation program of PCR. To demonstrate the feasibility of the automatic generation program, we evaluated its performance using experimental testbed.

Today’s vehicles include a complex symbiosis of intelligent electronic systems and integrated mechanical structures. In-vehicle networks provide an efficient method of communication between the various electronic components in an automobile. The communication protocols discussed in this paper are Local Interconnect Network (LIN), Controller Area Network (CAN) and FlexRay. LIN is used in low speed applications, CAN are used in medium speed applications and FlexRay is used in high speed applications. A gateway is a network node used to transfer data from one communication protocol to another. Vector CANoe is an all-round tool for the development, testing and analysis of entire ECU networks and individual ECUs. Vector CANoe uses a 3-phase development process that assists the user from the planning of the distributed system to the implementation of it. In this paper we have explained how to create 3 different networks (LIN, CAN and FlexRay) and also designed a gateway so that the messages can be transferred between different communication protocols. To start with we tested the design of the gateway using simulations and subsequently we have connected the necessary hardware and diagnosed the messages.

Today need for deterministic high data rate and high through put communication protocols for security critical applications and safety applications constantly increases. We can find easily many such applications in the automotive industry. As concepts like x-by-wire with x belongs to drive, steer, brake, etc., where steering arms and brake pipes are replaced by electric wires and integrated circuits, more and more popular, robust and fail-safe communication is needed to realize such functionality. Failures of these critical systems will almost immediately lead to severe accidents, personal injury and great loss to the society in all aspects. FlexRay is an option for upgrading existing network systems using CAN in the automotive industry as well as other industrial control applications. It could also be used for new applications in industrial automation, where safety and reliability in a work environment is of utmost importance, due to its deterministic approach to communication of the messages. This is helped by the use of a two channel topology where each channel is able to work independently, but the two channels can also be used to communicate the same information and as such has built in redundancy [1]. This paper will introduce the key features of the FlexRay protocol in automobile and power (Electric) window sliding design and implementation.

Because the FlexRay protocol has more than 70 configuration parameters and these parameters correlate with each other, designing a FlexRay network is a complex and difficult task. In this study, we propose a design framework that optimizes the two main FlexRay network parameters that are highly relevant to the application algorithm. The design process is composed of two steps for optimizing parameters. In the first step, the static slot length is optimized using a frame-packing algorithm. This algorithm binds network signals into static frames based on their periods and signal groups. In the second step, the communication cycle length is optimally designed with frame-scheduling algorithm and worst-case reponse time analysis. Based on the frame-scheduling algorithm, the response times are analyzed. The proposed design framework was applied to a unified chassis control system as a case study, and the analytical results were verified.

The car can meet the high demand of the security and stability of the system by using FlexRay bus, while it also can implement optimization of the cost. The paper introduces a system of nodes’ communication based on FlexRay technology, and the system constructed two nodes which are composed of main processors, communication controllers and bus transceivers. The paper implements the transmission of data between main processors and communication controllers by EBI (external bus interface). It is succeed in implementing the communication process of receiving data and sending data among different nodes. The results show that the data completely correct while the data rate is 10Mbps. Therefore, it verifies the reliability and real-time communication of FlexRay. And it also means that the designed node will play a significant role in X-By-Wire.

Automotive bus systems like FlexRay or CAN transmit safety critical data. To ensure correct functionality under all circumstances, extensive investigations about signal integrity and EMC have to be performed. To be able to use simulation in this validation process, suitable models for the components of the bus systems have to be developed. This paper shows how a combined transceiver model for signal integrity and EMC investigations can be created. The model shows good results in comparison to measurement data.

Nowadays, distributed embedded systems are employed in many safety-critical applications such as X-by-Wire. These systems are composed of several nodes interconnected by a network. Studies show that a transient fault in the communication controller of a network node can lead to errors in the fault site node (called original errors) and/or in the neighbor nodes (called follow-up errors). The communication controller of a network node can be halted due to an error, which may be a follow-up error. In this situation, a follow-up error leads to halt the correct operation of a fault-free controller while the fault site node, i.e. the faulty controller, still continues its operation. In this paper, an analysis shows that the occurrence probability of follow-up errors in communication protocols is noticeable. Consequently, it is important to provide a technique to recognize the error's nature, i.e. original or follow-up in each node. This paper proposes a novel low-cost monitoring technique to differentiate follow-up errors from original errors. The proposed technique is based on monitoring the operational states of a communication controller. In this paper, this technique has been applied to the FlexRay protocol. However, it is applicable for all communication protocols having an FSM-based description such as FlexRay, TTP/C, and TT-Ethernet. To evaluate the monitoring technique, a FlexRay-based network including 4 nodes was designed and implemented. The low-cost monitoring technique was as well implemented inside each node of the network. A total of 135,600 transient bit-flip faults were injected in the communication controller of one node. The results showed that about 6.0% of injected faults lead to original errors. This figure for follow-up errors was about 6.1%. The results as well showed that the accuracy of the proposed technique to differentiate between the follow-up and original errors is about 97% at merely 1.4% hardware overhead. This level of accuracy and cost makes the proposed technique a feasible solution to enhance the reliability of communication controllers.

Since several years the automotive industry strives for dealing with the fast growing system complexity, the increasing safety requirements and the increasing cost constraints of electronic components. In this work, we focus on two approaches: the time-triggered architecture which precisely specifies the system and its components both in the value and in the time domain, and component-based development which provides a framework for describing the system structure in a formalized way. We discuss in this paper the relationships between these two concepts and review methods for performing analysis and validation on top of component-based development frameworks. This combination is illustrated by a method for layered test and diagnosis for FlexRay communication architectures.