WO2009036834A1

WO2009036834A1 - Motor vehicle

Info

Publication number: WO2009036834A1
Application number: PCT/EP2008/006015
Authority: WO
Inventors: Oscar Iglesias Cid
Original assignee: Daimler Ag
Priority date: 2007-09-22
Filing date: 2008-07-23
Publication date: 2009-03-26
Also published as: DE102007045345A8; DE102007045345A1

Abstract

According to the invention, communication between electronic control devices in a motor vehicle takes place exclusively by means of a supply line structure. This is made possible by using a hybrid system: compared with conventional communication buses, the design of the electronic control devices is modified only in terms of the hardware, not the software. A transceiver transmits bits via the supply line structure, and all higher tasks defined in the open systems interconnection reference model of the International Organization for Standardization are performed by a microprocessor or microcontroller also known from conventional electronic control devices.

Description

motor vehicle

The invention relates to a motor vehicle and deals with the field of communication of electronic control units that has every motorized train today. Usually, the electronic control units communicate with each other via specific communication buses. In motor vehicles very specific communication bus systems are used. Nowadays, the most common is the CAN data bus (where CAN stands for Controller Area Network), the LIN data bus (where LIN stands for Local Interconnect Network), and the MOST optical data bus (where MOST stands for Media Oriented Systems Transport). For the future the use of Flexray data buses, of TTP data buses (where TTP stands for Time Triggered Protocol), and Firewire / USB data buses etc. is planned. For each type of communication or data bus, there are specific electronic control units that master the respective protocol.

Outside the field of motor vehicles, it is known to send data via (voltage) supply lines. This is also referred to by the English term "Powerline Communications", PLC for short.

It has already been considered to use PLC in motor vehicles. For example, patent documents of Robert Bosch GmbH are concerned with the subject matter. DE 101 42 408 A1 describes that in a motor vehicle communication via the supply lines can take place in the event of failure of the actual communication bus, if the control units are equipped with a PLC transceiver (where a transceiver is a transceiver). In DE 101 42 409 A1 it is described that a supply line structure in a motor vehicle can take place for the transmission of information between motor vehicle components, if the Supply line structure has separate, electrically isolated from the vehicle body supply lines as return lines from the components of at least one energy source of the motor vehicle.

In practice, a communication via supply lines has not yet been used in motor vehicles. One of several reasons for this is that so far no suitable protocols have been developed for all communication tasks. Different communication tasks, as they occur in the communication networks are described in the so-called OSI reference model (Open Systems Interconnection Reference Model) of the international standardization organization (ISO). The communication tasks are assigned to different layers. The sender and receiver have an instance for each layer, and the communication between instances associated with the same layer is via a predetermined protocol. It has proven to be problematic to develop protocols for all seven layers of the USI reference model that can be used in communication over the utility lines.

It is an object of the invention to show a way, how actually all communication can be done in a motor vehicle via the supply lines.

The object is achieved by a motor vehicle having the features according to claim 1.

Thus, the motor vehicle comprises a plurality of electronic control units, which are fed via a supply line structure with electrical energy, wherein in the motor vehicle, a separate bus for communication by the control units or with the control devices is provided, and wherein each control device, a transceiver for coupling of signals in the supply line structure and for coupling out signals from the supply line structure. The basic idea that can be dispensed with the separate communication bus or data bus, is that the transmitter-receiver shares the communication tasks of the electrical control unit with another unit. This happens because communication tasks according to at least the lowest layer of OSl reference model associated with the transceiver, which meets them according to a tuned to the use of the supply line structure as a communication bus operation. On the other hand, according to higher layers of the OSI reference model, the communication tasks are assigned to the further unit as the layer assigned to the transceiver, which fulfills the communication tasks associated therewith in accordance with a normal mode of operation when using communication buses other than supply line structures, in particular conventional communication buses used in motor vehicles.

In other words, it is a hybrid solution where the adaptation to the use of the communication line structure is only partial, namely in the lowest layer or multiple lower layers of the OSI reference model, so that only for this lowest layer (s) a suitable protocol must be provided, while otherwise on the known protocols, for example for CAN buses, etc. (see the list given at the beginning) can be made.

The invention makes it possible to actually dispense with a separate bus for communication. This saves costs for the bus cables themselves and for their installation.

The above-mentioned further unit is usually a microprocessor or a microcontroller, namely, such a microprocessor or microcontroller of the kind can be used, as it is used in commonly used on conventional motor vehicles communication buses connectable controllers or is commonly used. As a result, the development of the electronic control devices is particularly inexpensive, and it can be easily redesigned by an electronic control equipment supplier who typically builds them for use with a separate communication bus simply by replacing the transceiver. This can be expressed that the electronic control unit differs from conventional control units used in the use of a separate communication bus only in the hardware, but not in the software, because the software is stored on the microprocessor or microcontroller. Specifically, the microprocessor or microcontroller (ie the other unit) can thus operate as if it were intended for communication via a CAN data bus, a LIN data bus, a MOST optical data bus or a Flexray bus (with then associated other transmitter-receiver) , If other bus systems are used in the future, the further unit may also be provided for them, so that they do not have to be developed specifically for the realization of the invention, because then you have the above-mentioned cost advantage.

Of the seven layers of the OSI reference model, the transmitter-receiver in a particularly easy-to-implement embodiment can only be assigned the task of bit transmission - which corresponds to the lowest layer. The further unit preferably assumes the task of performing the tasks of all six higher layers of the OSI reference model.

Hereinafter, a preferred embodiment of the invention will be described with reference to the drawing which schematically shows an electronic control unit connected to a supply line structure as used in the present invention.

In the present invention, all communication is done by electronic control units (ECUs) via a power supply structure. The supply line structure serves to supply the electronic control device with a voltage sufficient for its operation. In a manner known per se, the electronic control unit has a microprocessor (μ P) or a microcontroller (// C).

This communicates with a transceiver (PLC transceiver), which is specially designed for the exchange of information about the supply line structure.

The electronic control unit differs from conventional control units, as used in motor vehicles, only by the transceiver, but not by the microprocessor or the microcontroller. Usually, the microprocessor or microcontroller performs higher communication tasks in the electronic control unit than the transceiver. In the present case, the transceiver merely has to perform the task of bit transmission via the supply line structure. This corresponds to layer 1 of the OSI reference model of the International Standardization Organization (ISO). The other higher layers for communication tasks according to the OSI reference model are the data link layer, the network layer, the transport layer, the session layer, the presentation layer, and the application layer. The tasks corresponding to these further layers are performed by the microprocessor or microcontroller. In this case, it is possible to link to known protocols, and only the protocol for the bit transmission, that is to say for the transceiver, must be specially adapted to the use of the supply line structure as the communication bus.

For example, you can build a CAN-PLC hybrid network, in which only the supply line structure is used as a communication bus and the electronic control unit, which is usually used in the use of CAN buses is rebuilt by the usual CAN transceiver (CAN Transceiver) is replaced by the new transceiver (PLC transceiver). For example, in conventional electronic CAN controllers, the CAN transceiver TEJA1054 is used, and this must only be replaced by a suitable PLC transceiver. But you can still use the CAN microcontroller in the electronic control unit.

In the same way, a MOST-PLC hybrid network can be set up: standard electronic control units for connection to MOST buses include a photodiode transmitter-receiver, and this only has to be replaced by a PLC transceiver. On the other hand, the electronic control unit commonly used for connection to MOST buses can also use the usual microcontroller, for example the OS8104, in the invention.

All this can be formulated briefly so that compared to conventional control devices in the invention, the hardware of the electronic control units is changed, the software is not, that is, what is programmed into the microprocessor or microcontroller. This can save the separate data bus lines and use only the utility line structure and has the effect of significant cost savings.

Claims

claims

1. Motor vehicle with a plurality of electronic control units (ECU) ₁ which are fed via a supply line structure (power supply) with electrical energy, wherein in the motor vehicle no separate bus for communication by the control units (ECU) or with the control units (ECU) is provided, and wherein each control unit (ECU) comprises a transceiver (PLC transceiver) for coupling signals into the power supply structure (power supply) and for coupling out signals from the power supply structure (power supply), wherein the transceiver (PLC transceiver), communication tasks of the electric control unit (ECU) with another unit (// P- // C) divides by communication tasks according to at least the lowest layer of the Open Systems Interconnection reference model of the international standardization organization (the OSI reference model) the transmitter Receivers (PLC transceivers) are assigned, they acc a function adapted to the use of the power supply structure as a communication bus, and by performing communication tasks according to higher layers of the OSI reference model than the further unit (// P- // C) associated with the transceiver (PLC transceiver). are assigned, the communication tasks assigned to it according to a different when using supply line structures Communication buses usual way of working met.

2. Motor vehicle according to claim 1, wherein the further unit is a microprocessor (μ P) or microcontroller (// C) is the way it is used in connectable to conventional communication buses used in motor vehicles control units.

3. Motor vehicle according to claim 1 or 2, wherein the further unit (μ P- μ C) operates as if it were for communication via a Controller Area Network data bus, a Local Interconnect Network data bus, a Media Oriented Systems Transport optical data bus and / or a Flexraybus provided.

4. Motor vehicles according to one of the preceding claims, wherein the transceiver (PLC transceiver) perceives only the task of bit transmission.