Byteflight

Abstract: Flexible time division multiple access (FTDMA) is a medium access mechanism that some modern popular networks for use in passenger vehicles, such as Byteflight and FlexRay, rely on. Its development was driven explicitly by the new needs of automotive x-by-wire systems, which could not be satisfied by the existing solutions. The FTDMA technique was conceived primarily to overcome the limitations of controller area network and, in particular, for supporting high performance real-time communications. Even though this access scheme is mainly suitable for asynchronous transmissions, it can be adopted profitably for synchronous exchanges as well. In this paper, the main features of FTDMA are analyzed, and its performance is evaluated for different kinds of communications that have to be supported in today's vehicles.

Abstract: This paper compares the emerging time-triggered protocols that will find use in automotive control networks. At present there is no de facto standard in the automotive industry for in-vehicle networking based on the time-triggered model. As the industry is pushing towards incorporating X-by-wire technology (X standing for steer, brake, shift, etc.) for future cars, car manufacturers are working towards agreeing industry standards for X-by-wire control system applications. Currently there are four protocols based on the time-triggered paradigm which are competing for the X-by-wire automotive market. These protocols are TTCAN, TTP/C, Flex Ray and Byteflight.

Abstract: Byteflight is a high performance communication network conceived for the use in passenger vehicles, which features the advantages of both the synchronous and asynchronous transmission schemes. Its development was driven by the new needs of automotive systems, which could not be satisfied by the existing solutions. In this paper, the main features of Byteflight are analysed - pointing out its advantages and drawbacks - and its performance is evaluated for the different kinds of communications that have to be supported in today's vehicles as well as in advanced automated manufacturing systems.

Abstract: There is a clear trend in automobile development towards using electronic systems instead of mechanical components and towards realizing an increasing number of convenience and safety functions while at the same time taking into consideration the environment. Consequently, vehicle electronics are becoming increasing complex and the number of functions, sensors, and actuators is growing fast. These requirements cannot be met with a central control unit. The solution is to network the various electronic modules using a high-performance data bus. This makes it possible to reduce the complexity of the wiring and to make multiple use of sensor data in order to integrate the individual functions in such a way that they form an intelligent overall vehicle. The high-performance bus required to make this possible is now available: Together with the companies Motorola, ELMOS, Infineon and Tyco EC, BMW AG has developed the byteflight high-performance data bus for safety-related applications. Fully integrated, inexpensive electronic components are already available for the construction of a complete bus system based on fiber optics technology. The first application in highvolume automobile production will start within the next year and will include passive-safety and body functions.