CN204256438U

CN204256438U - Automobile double CAN topological structure

Info

Publication number: CN204256438U
Application number: CN201420784195.9U
Authority: CN
Inventors: 何平国; 杨晶晶; 陈晓俊
Original assignee: Beiben Trucks Group Co Ltd
Current assignee: Beiben Trucks Group Co Ltd
Priority date: 2014-12-11
Filing date: 2014-12-11
Publication date: 2015-04-08
Anticipated expiration: 2024-12-11

Abstract

The utility model relates to a kind of automobile double CAN topological structure, belongs to the design field of automotive electronics and automobile safety system.This structure comprises power bus, Vehicle Body Bus, the first communication main line and second communication main line, described first communication main line and second communication main line redundancy each other, form main line bus, power bus and Vehicle Body Bus form branch line bus, power bus is connected by communicate with first respectively main line and second communication main line of the first gateway, Vehicle Body Bus is connected by communicate with first respectively main line and second communication main line of the second gateway, and the described first communicate main line and second communication main line is controller local area network's CAN.The utility model adopts dual CAN bus to devise a kind of automotive networking topological structure, can be used in the reliability that lifting CAN communicates in automotive control system, ensures the reliability of operation of automobile.

Description

Automobile double CAN topological structure

Technical field

The utility model relates to the design field of automotive electronics and automobile safety system, is specifically related to a kind of automobile double CAN topological structure.

Background technology

Along with automotive circuit diagram, the improving constantly of intelligence degree, the quantity of automobile electric control system constantly increases, the continuous lifting of automobile electric control system performance.Message exchange between each electric-control system gets more and more, thus wire harness is connected become very complicated, more difficult, the reliability of assembling maintenance is difficult to some row problems such as guarantee.Automotive networking bus system not only can be shared information, be saved wire harness, can also provide abundanter function, thus the value of improving product and competitive power, meet the demand of the aspect such as automobile reliability, comfortableness.

CAN (Controller Area Network, controller local area network) bus be German BOSCH company at 20th century the mid-80, the one communication of developing for the exchanges data solved between each electronic-controlled installation and control technology.The serial communication network that CAN is a kind of effective support distributed AC servo system and controls in real time, communication media is twisted-pair feeder, concentric cable or light transmitting fiber, and traffic rate can reach 1Mb/s.At present, CAN has become most widely used fieldbus in the world, and has derived the communication protocol SAEJ1939 being exclusively used in heavy truck fieldbus.

Although CAN self has stronger EDC error detection and correction ability, but for CAN vehicle, many important time real data are all exchanged by CAN network, once CAN network goes wrong, car load data cannot exchange, and cause vehicle cisco unity malfunction.

Utility model content

(1) technical matters that will solve

The technical problems to be solved in the utility model is: how to design a kind of automobile double CAN topological structure, can be applied to the reliability that lifting CAN communicates in automotive control system.

(2) technical scheme

In order to solve the problems of the technologies described above, the utility model provides a kind of automobile double CAN topological structure, comprise power bus, Vehicle Body Bus, first communication main line and second communication main line, described first communication main line and second communication main line redundancy each other, form main line bus, power bus and Vehicle Body Bus form branch line bus, power bus is connected by communicate with first respectively main line and second communication main line of the first gateway, Vehicle Body Bus is connected by communicate with first respectively main line and second communication main line of the second gateway, described first communication main line and second communication main line are controller local area network's CAN.

Preferably, the terminal resistance of described branch line bus and main line bus is arranged on two of every bar bus farthest on physical node.

(3) beneficial effect

The utility model adopts dual CAN bus to devise a kind of automotive networking topological structure, can be used in the reliability that lifting CAN communicates in automotive control system, ensures the reliability of operation of automobile.

Accompanying drawing explanation

Fig. 1 is the application schematic diagram of the utility model embodiment;

Fig. 2 is the hardware structure diagram of the node that the utility model embodiment is connected in use.

Embodiment

For making the purpose of this utility model, content and advantage clearly, below in conjunction with drawings and Examples, embodiment of the present utility model is described in further detail.

As shown in Figure 1, a kind of automobile double CAN of the utility model embodiment topological structure, comprise power bus 1 (being the high-speed bus for power drive system), Vehicle Body Bus 2 (being the low speed bus for bodywork system), first communication main line 3 and second communication main line 4, described first communication main line 3 (black line thicker in Fig. 1) and second communication main line 4 (in Fig. 1 relative first communicate the thinner black line of main line 3) redundancy each other, form main line bus, power bus 1 and Vehicle Body Bus structure 2 one-tenth branch line buses, power bus 1 is connected by communicate with first respectively main line 3 and second communication main line 4 of the first gateway, Vehicle Body Bus 2 is connected by communicate with first respectively main line 3 and second communication main line 4 of the second gateway, described first communication main line 3 and second communication main line 4 are controller local area network's CAN.Power bus 1, Vehicle Body Bus 2 can be CAN.

In the present embodiment, the terminal resistance of branch line bus and main line bus is arranged on two of every bar bus farthest on physical node.In use, described first gateway is arranged in chassis power plant module DGM 5 topological structure of the present embodiment.Described second gateway is arranged in car body control module BCM 6.The node that described power bus connects comprises anti-lock braking system abs controller, retarder RET, wheel box (TCU+WSK), engine controller EMS and automatic differential lock ADM.The node that described Vehicle Body Bus connects comprises central air-charging and air-discharging system CTIS, additional cooler AFC and rear chassis module RCM.The node that described first communication bus is connected with second communication bus comprises automotive diagnostic system and instrument IC.

As shown in Figure 2, wherein, each node adopts two-way CAN transceiver to the CAN network of same function to the hardware design of each node; Every road transceiver is connected respectively to the different CAN controller mouths of main control chip; Two-way CAN transceiver can work alone; The management of main control chip to two-way CAN is independently; When physical fault appears in a road CAN, main control chip automatically switches to another road CAN according to the agreement of correspondence and gets on.

In network, all node timed sending systems specify message to there is mark as node.When node in main line bus is as gateway, mark (Monitored message) is existed to all nodes in its subnet and monitors.Monitoring nodes in the main line bus mark that the message (Alive message) that sends of other node cycles exists as it on it.

Data acquisition rule between main line bus node is:

Under original state, as recipient, the node acquiescence in main line bus adopts all message on A channel to be information source, until the disappearance (its alive message time-out) of certain node on A channel detected.As sender, in main line bus, each node is responsible for same message to be sent to A channel and channel B simultaneously.

Node (such as M) in main line bus detects that on A channel existence mark (alive message) time-out of another node (such as N) on passage A or self (M) enter BUS OFF state on A channel, then ignore node (N) institute send out message and in automatic detection channel B node (N) send out message.If now in channel B this node (N) exist mark (alive message) exist time-out and in channel B node self (M) do not enter Bus-Off state, then node (M) obtains from channel B the message that node (N) sends immediately.

Node (M) in main line bus receive in channel B certain node (N) in channel B send out message while detect this node (N) on A channel exist mark (alive message) effectively and effective status continue to reach node N send out 3 times (node M is not in BusOff state on passage A) of Alive message cycle, then return to original state immediately.

If the existence mark of main line bus node on A channel and channel B (alive message) is all overtime or enter BusOff state, then judge that this node lacks in main line bus, monitor node record DTC code (can carry out reporting to the police at HMI interface for instrument).

If in main line bus receiving node (M) detect another node (N) on A channel feature message (the non-alive message) time-out sent out but node (N) exists mark (alive message) time-out (and node M is not in BusOff state on passage A), then receiving node (M) detects the existence mark (alive message) of monitored node (N) in channel B and the state of this feature message immediately.If in channel B there is mark (alive message) effectively (not time-out in node (N), and node M is not in BusOff state in channel B) and this feature message is effectively (not time-out), then adopt the data that in channel B, this feature message is corresponding.If now the existence mark of monitored node (N) invalid (alive message time-out) or this feature message time-out in channel B, use the default value of this feature message.If effective (maintenance " time-out " state sends 3 times of cycle more than Alive and node M is not in BusOff state on passage A) of the existence mark (alive message) of monitored node on A channel (N) detected in arbitrary situation and this feature message effective (maintenance " overtime " state exceedes 3 times that feature message sends the cycle), this feature message should be obtained at A channel.

Data acquisition rule between main line bus node and branch line bus node:

Between node (except the gateway on branch line) in branch line bus (hereinafter referred to as branch line), do not support mutual function for monitoring.On gateway collection branch line on branch line each node particular message (Monitored message) as these nodes online mark (" online " position) and form corresponding privately owned message and send on main line, this message is also defined as the Alive message of gateway simultaneously.Transmission cycle of this Alive message monitors by gateway on the branch road of place 2 times of the message cycle that in message, the transmission cycle is the shortest.

Under original state, the rule adopted when main line bus node (M) receives the feature message of a certain branch line node (P) is as follows:

On A channel:

If ● node (M) be not in Busoff state;

● and the gateway of node (P) place branch road send out Alive message time-out and non-timeout mode keep Alive message to send 3 times of cycle;

● and " online " position corresponding to Alive message interior joint P is effective;

● and node P send out message time-out and non-timeout mode keeps this feature message

3 times of transmission cycle;

When above-mentioned condition is met, node (M) gathers message from A channel, otherwise in channel B, test above-mentioned condition, if above-mentioned condition exists in channel B, then in channel B, gather message, otherwise node M uses the default value of message and does not gather message from any one passage.When node (M) does not gather message on A channel, and detect that above-mentioned condition is met on A channel, then should be switched on A channel immediately.

As can be seen from the above embodiments, the utility model adopts dual CAN bus to devise a kind of automotive networking topological structure for improving automotive control system reliability, by fail-safe analysis and verification experimental verification, confirm and adopt this topological structure to coordinate the functional node that it connects can promote the reliability that CAN communicates in automotive control system, the reliability of operation of guarantee automobile.

The above is only preferred implementation of the present utility model; should be understood that; for those skilled in the art; under the prerequisite not departing from the utility model know-why; can also make some improvement and distortion, these improve and distortion also should be considered as protection domain of the present utility model.

Claims

1. an automobile double CAN topological structure, it is characterized in that, comprise power bus, Vehicle Body Bus, first communication main line and second communication main line, described first communication main line and second communication main line redundancy each other, form main line bus, power bus and Vehicle Body Bus form branch line bus, power bus is connected by communicate with first respectively main line and second communication main line of the first gateway, Vehicle Body Bus is connected by communicate with first respectively main line and second communication main line of the second gateway, described first communication main line and second communication main line are controller local area network's CAN.

2. structure as claimed in claim 1, is characterized in that, the terminal resistance of described branch line bus and main line bus is arranged on two of every bar bus farthest on physical node.