CN101425951A

CN101425951A - Vehicle body CAN bus control system

Info

Publication number: CN101425951A
Application number: CNA2007101340941A
Authority: CN
Inventors: 徐福芳
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-10-29
Filing date: 2007-10-29
Publication date: 2009-05-06

Abstract

An auto body CAN bus control system. The CAN bus technology substitute the digital serial communication protocol for traditional parallel wire control and possesses function of point-to-point, one point-to-multipoint and universal broadcasting transmission and achieves data resource sharing; The CAN reduces input demand for combined switch and other switch; current passing combined switch in traditional power supply system is supplied current for electricity consumer itself and amounts to several amp. to dozens of amp., while current is only several milliampere when changing to multi-path bus transmission system and accounts for one part per thousand of original current, thus reliability of parts is promoted; the electric appliances are generally connected by following strictly the SAEJ1939 communication protocol; the modularized, integrative and miniaturized structure facilitates batch production and spatial disposition; the new node can be directly hanged to bus when the CAN bus needed to be enlarged. It is subject to few cabling, enlarging and remodeling without developing and changing wiring harnesses, thereby simplifying production process and reducing production cost.

Description

Vehicle body CAN bus control system

Technical field:

The present invention relates to a kind of automobile bus control system, relate in particular to a kind of vehicle body CAN bus control system.

Background technology:

Develop rapidly along with the vehicle electric technology, electronic-controlled installation on the vehicle and electronics final controlling element are more and more, for example electronic fuel injection system, automatic speed-changing system, Active suspension, anti-lock brake system (ABS), air bag device and automatically controlled door and window device etc.These advanced functions make that intellectuality, comfortableness, the fail safe of automobile are more and more higher, the automotive electronics electric system is become become increasingly complex.Traditional vehicle electric system uses point-to-point single communication mode between the electronic installation, each electronic control unit all has a cover sensing and the wiring system of oneself, rare contact between them, must cause the vehicle body wiring huge and complicated like this, the lead length overall of a car surpasses more than the 2km, not only to consume a large amount of plain conductors, and because wiring is crisscross, also can cause serious electromagnetic interference, the fail safe reliability of the control system of automobile integral body is reduced, and the breakdown maintenance difficulty increases.

Goal of the invention:

The present invention seeks to make the large quantities of data message of automobile in different electronic units, to share, can make the car load wire harness of automobile reduce 60%～85%.Adopt a plurality of control modules to be articulated on the CAN bus,,, can not only increase substantially the fail safe and the reliability of automotive control system, be convenient to the increase and the renewal of automobile controlled function applicable to the Electronic Control of different vehicle by the single-chip microcomputer intelligent management.

Summary of the invention:

In order to overcome existing automobile combined switch above shortcomings, the invention provides a kind of vehicle body CAN bus control system.

The technical solution used in the present invention is:

The CAN bussing technique substitutes traditional parallel lead control with digitized serial communication protocol, and bus has point-to-point, some the multiple spot and the overall situation is broadcasted the function that transmits data, reaches data resource and shares:

1) the CAN bus adopts unique non-destructive bus arbitration technology, and priority node preferentially transmits data.

2) the CAN bus is each node of the many main websites bus node of other on network transmission at any time information, and is regardless of the principal and subordinate.

3) transmission rate of bus can be set according to customer requirements.

4) every hardwood data all have CRC check and other error detection measure.

The quantity and the distribution situation of 5) each input of bus, output module can be provided with flexibly according to actual instructions for use.

6) adopt modular construction, when system extension, main body need not change, and only needs partial alteration, has improved Vehicular system design and configuration flexibility, promptly can realize the variation and the expansion of whole vehicle functions easily by soft, the hardware change of network.

7) adopt two twisted-pair feeders to transmit as body data.

Advantage of the present invention:

By the present invention, can realize:

1) requirement to unit switch and the input of other switches reduces, the tradition electric power system is the supply current of electrical appliance itself by the electric current of unit switch, can reach several amperes to tens amperes, use the multiple bus transmission system instead and only have several milliamperes later on, be the one thousandth of original electric current, improved the reliability of parts;

2) SAE J1939 communication protocol is followed in strictness, realizes the generalization butt joint of electric equipment;

3) modularization, integrated, microminiaturized structure are convenient to tissue and are produced in batches and spatial placement;

When 4) the CAN bus need expand, can directly new node be hung on the bus, thereby cabling is few, system expands easily, and remodeling flexibly.Do not need to develop again and change the car load wire harness, simplify production technology, reduce production cost.

Description of drawings:

The present invention is described further below in conjunction with accompanying drawing:

Fig. 1 is the functional block diagram of CAN body control system;

Fig. 2 is automobile CAN-bus network topology structure figure;

Fig. 3 is a sedan limousine CAN bus electronic control system schematic diagram.

Embodiment:

Be example explanation the specific embodiment of the present invention with the Ou Manchong card below:

Network node is optimized in the body network system design, sends what concrete messages in the network, and data are respectively which node to be sent to which node from,

Modeling, emulation that the CANalyzer of network system Simulation Application Germany Vector Informatik company exploitation and CANoe software carry out system bus network node and whole system are to reduce the software development workload.

Each controller node of automatically controlled hardware development all need carry out stand-alone development at the characteristics of self, after controlled function realizes, utilize bus interface that other nodes of this real node and CANoe software simulation are connected, test the function of real node: as communication, error correction.Like this, the node of system is a concurrent development, can not be subjected to the influence of other node development procedures.

Automatically controlled software MATLAB/Simulink/Stateflow modeling and simulating, control strategy downloads among the Dspace rapid prototype development instrument MicroAutoBox through MIL, SIL, PIL test, carries out control strategy analysis and test.After ECU (Electrical Control Unit) machines, Simulink controlling models process model conversion through emulation testing, obtain the TargetLink model, but this model auto-scaling, code generate and provide the support to OSEK operating system, generating through code just can controlled tactful source code.

Bottom layer driving software adopts and manually writes, and develops the diagnostics interface of CAN bus with corresponding developing instrument: the demarcation interface of supporting the CCP agreement; Communication interface with CANOE development support J1939 agreement; ISO15765 failure diagnosis agreement based on CAN.

Hand-written code and automatic generating code are integrated in the integrated developing instrument CodeWarrior of MCU, execute file that generation can move and image file, image file turns back in the Targetlink model, just can generate the demarcation file, just can realize matching and calibration to electric-control system by CANape.But utilize MATLAB instrument generation model report file, make things convenient for software administration.Utilize the Dspace simulation hardware Simulator can be, particularly zero boundary's condition test to software test.

Claims

A kind of vehicle body CAN bus control system, it is characterized in that the CAN bussing technique substitutes the parallel lead control of tradition with digitized serial communication protocol, bus has point-to-point, a bit to the function of multiple spot and overall situation broadcasting transmission data, reaches data resource and shares:

1) the CAN bus adopts unique non-destructive bus arbitration technology, and priority node preferentially transmits data.

2) the CAN bus is each node of the many main websites bus node of other on network transmission at any time information, and is regardless of the principal and subordinate.

3) transmission rate of bus can be set according to customer requirements.

4) every hardwood data all have CRC check and other error detection measure.

The quantity and the distribution situation of 5) each input of bus, output module can be provided with flexibly according to actual instructions for use.

6) adopt modular construction, when system extension, main body need not change, and only needs partial alteration, has improved Vehicular system design and configuration flexibility, promptly can realize the variation and the expansion of whole vehicle functions easily by soft, the hardware change of network.

7) adopt two twisted-pair feeders to transmit as body data.