CN115378754A

CN115378754A - CAN communication redundancy method and communication device

Info

Publication number: CN115378754A
Application number: CN202110557716.1A
Authority: CN
Inventors: 裴建龙
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-05-21
Filing date: 2021-05-21
Publication date: 2022-11-22
Also published as: WO2022242314A1

Abstract

The application provides a CAN communication redundancy method and a communication device, wherein the method comprises the following steps: the multi-path CAN channel is respectively connected with a plurality of network nodes; and when detecting that a first CAN channel in the plurality of CAN channels has a fault, controlling a multiplexer to switch the CAN channel connected with the first network node to a first backup CAN channel, wherein the first CAN channel comprises the CAN channel connected with the first network node. The technical scheme can reduce the cost of a communication system and the complexity of communication devices while ensuring the reliability of network communication in a vehicle.

Description

CAN communication redundancy method and communication device

Technical Field

The present application relates to the field of communications, and more particularly, to a method and a communication apparatus for CAN communication redundancy.

Background

In designing network communication in an automobile, in order to ensure reliability of communication, redundancy design of Controller Area Network (CAN) communication is generally performed. However, in the case of the redundant design, although the reliability of the network communication system is improved, the problems of cost increase, complex in-vehicle wiring structure, and the like are inevitably brought about.

Therefore, how to reduce the cost of the in-vehicle CAN communication system and the complexity of the in-vehicle harness structure while ensuring reliable communication becomes a technical problem to be solved.

Disclosure of Invention

The application provides a CAN communication redundancy method and a communication device, and the technical scheme CAN reduce the cost of an in-vehicle communication system and the complexity of an in-vehicle wiring harness structure while ensuring reliable in-vehicle communication.

In a first aspect, a method for CAN communication redundancy is provided, the method comprising: the multi-path CAN channel is respectively connected with a plurality of network nodes; and when detecting that a first CAN channel in the plurality of CAN channels has a fault, controlling a multiplexer to switch a CAN channel connected with a first network node to a first backup CAN channel, wherein the first CAN channel comprises a CAN channel connected with the first network node.

Based on the embodiment of the application, one backup channel is designed for a plurality of CAN channels, and when the CAN channel connected with the first network node breaks down, the multiplexer CAN be controlled to switch the CAN channel connected with the first network node to the first backup CAN channel. According to the technical scheme, the backup of multiple CAN channels CAN be realized through one backup CAN channel, so that the reliability of communication in the vehicle CAN be ensured, and the cost of a communication system in the vehicle and the complexity of a wiring harness structure in the vehicle CAN be reduced.

With reference to the first aspect, in certain implementations of the first aspect, the controlling the multiplexer to switch the CAN channel connected to the first network node to the first backup CAN channel when detecting that a first CAN channel of the multiple CAN channels has a fault includes: and controlling the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first CAN channel and connect the bidirectional switch to the first backup CAN channel.

Based on the embodiment of the application, the multiplexer comprises a plurality of bidirectional switches, and when the CAN channel corresponding to one of the external network nodes is detected to have a fault, the switching from the fault CAN channel to the backup channel CAN be realized by controlling the disconnection and connection of the bidirectional switches.

With reference to the first aspect, in certain implementations of the first aspect, the controlling the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first CAN channel and connect to the first backup CAN channel includes: and sending first switching indication information to the multiplexer, wherein the first switching indication information is used for indicating the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first CAN channel and connect the bidirectional switch to the first backup CAN channel.

Based on the embodiment of the application, when the CAN channel needs to be switched, the switching indication information is sent to the multiplexer to indicate the switching from the fault channel to the backup channel.

With reference to the first aspect, in certain implementations of the first aspect, the method further includes: when detecting that a second CAN channel in the plurality of CAN channels has a fault, determining the priority of the first CAN channel and the priority of the second CAN channel; and when the priority of the second CAN channel is greater than that of the first CAN channel, controlling the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first backup CAN channel, disconnect the bidirectional switch corresponding to the second network node from the second CAN channel, and connect the bidirectional switch corresponding to the second network node to the first backup CAN channel.

Based on the embodiment of the application, when the two CAN channels are detected to have faults, the CAN channel with high priority is switched to the backup channel, so that the communication reliability of important data is ensured.

With reference to the first aspect, in certain implementations of the first aspect, the determining the priority of the first CAN channel and the second CAN channel includes: and determining the priority of the first CAN channel and the second CAN channel according to the data transmitted by the first CAN channel and the second CAN channel.

Based on the embodiment of the application, the priority of the CAN channel CAN be judged through the data transmitted in the CAN channel, so that the communication reliability of important data CAN be ensured.

With reference to the first aspect, in certain implementation manners of the first aspect, the controlling the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first backup CAN channel, disconnect the bidirectional switch corresponding to the second network node from the second CAN channel, and connect the bidirectional switch corresponding to the second network node to the first backup CAN channel includes: and sending second switching indication information to a multiplexer, wherein the second switching indication information is used for indicating the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first backup CAN channel, disconnect the bidirectional switch corresponding to the second network node from the second CAN channel, and connect the bidirectional switch corresponding to the second network node to the first backup CAN channel.

With reference to the first aspect, in certain implementation manners of the first aspect, the first CAN channel includes at least two CAN channels, a priority of a CAN channel connected to the first network node is greater than a priority of a CAN channel connected to a third network node, and the CAN channel connected to the third network node is a channel of the at least two CAN channels except for the CAN channel connected to the first network node.

Based on the embodiment of the application, when the first CAN channel comprises a plurality of CAN channels, the priority of the CAN channel connected with the first network node is higher, so that the communication reliability of important data is ensured.

With reference to the first aspect, in certain implementations of the first aspect, the method further includes: and when detecting that a third CAN channel in the multi-channel CAN channels has a fault, controlling the multi-channel selector to switch the CAN channel connected with a third network node from the third CAN channel to a second backup CAN channel, wherein the second backup CAN channel and the first backup CAN channel are different CAN channels.

Based on the embodiment of the application, the technical scheme designs two backup channels, so that the reliability of communication in the vehicle can be improved.

With reference to the first aspect, in certain implementations of the first aspect, the method further includes: when detecting that a fourth CAN channel in the plurality of CAN channels has a fault, determining the priority of the first CAN channel, the priority of the third CAN channel and the priority of the fourth CAN channel; when the priority of the fourth CAN channel is greater than that of the first CAN channel and the priority of the first CAN channel is greater than that of a third CAN channel, controlling the multiplexer to disconnect the third network node from the second backup CAN channel and switch the CAN channel connected with the fourth network node from the fourth CAN channel to the second backup CAN channel; or when the priority of the fourth CAN channel is greater than that of the first CAN channel and the priority of the first CAN channel is less than that of the third CAN channel, controlling the multiplexer to disconnect the first network node from the first backup CAN channel and switch the CAN channel connected with the fourth network node from the fourth CAN channel to the first backup CAN channel.

Based on the embodiment of the application, under the condition that two backup channels exist, the two CAN channels with high priority levels are switched to the two backup channels, so that the communication reliability of important data in a vehicle is ensured.

In a second aspect, a method of CAN communication redundancy is provided, the method comprising: the multi-path CAN channel is respectively connected with a plurality of network nodes; when the CAN channels in the plurality of paths of CAN channels are detected to have faults, determining the priorities of the CAN channels; and controlling a multiplexer to respectively switch the two CAN channels with high priority in the at least two CAN channels to the two backup CAN channels.

In the embodiment of the application, two backup CAN channels are designed for the communication system, and when a plurality of CAN channels simultaneously break down, the two CAN channels with high priority CAN be respectively switched to the two backup channels.

Since the importance degree of the data transmitted by each CAN channel CAN be different, the technical scheme is favorable for ensuring the communication reliability of the important data.

In a third aspect, a communication apparatus is provided, which includes: a memory to store instructions; a processor for reading the instructions, which when executed by the processor, cause the communication device to perform the steps of: the multi-path CAN channel is respectively connected with a plurality of network nodes; and when detecting that a first CAN channel in the plurality of CAN channels has a fault, controlling a multiplexer to switch a CAN channel connected with a first network node to a first backup CAN channel, wherein the first CAN channel comprises a CAN channel connected with the first network node.

With reference to the third aspect, in certain implementations of the third aspect, the multiplexer includes a plurality of bidirectional switches in one-to-one correspondence with the plurality of network nodes, and the instructions, when executed by the processor, cause the communication apparatus to perform the steps of: and controlling the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first CAN channel and connect the bidirectional switch to the first backup CAN channel.

With reference to the third aspect, in certain implementations of the third aspect, the instructions, when executed by the processor, cause the communication apparatus to perform: and sending first switching indication information to the multiplexer, wherein the first switching indication information is used for indicating the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first CAN channel and connect the bidirectional switch to the first backup CAN channel.

With reference to the third aspect, in certain implementations of the third aspect, the instructions, when executed by the processor, cause the communication apparatus to perform the steps of: when a second CAN channel in the plurality of CAN channels is detected to have a fault, determining the priority of the first CAN channel and the priority of the second CAN channel; and when the priority of the second CAN channel is greater than that of the first CAN channel, controlling the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first backup CAN channel, disconnect the bidirectional switch corresponding to the second network node from the second CAN channel, and connect the bidirectional switch corresponding to the second network node to the first backup CAN channel.

With reference to the third aspect, in certain implementations of the third aspect, the instructions, when executed by the processor, cause the communication apparatus to perform the steps of: and determining the priority of the first CAN channel and the second CAN channel according to the data transmitted by the first CAN channel and the second CAN channel.

With reference to the third aspect, in certain implementations of the third aspect, the instructions, when executed by the processor, cause the communication apparatus to perform: and sending second switching indication information to a multiplexer, wherein the second switching indication information is used for indicating the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first backup CAN channel, disconnect the bidirectional switch corresponding to the second network node from the second backup CAN channel, and connect the bidirectional switch corresponding to the second network node to the first backup CAN channel.

With reference to the third aspect, in some implementation manners of the third aspect, the first CAN channel includes at least two CAN channels, a priority of a CAN channel connected to the first network node is greater than a priority of a CAN channel connected to a third network node, and a CAN channel connected to the third network node is a channel of the at least two CAN channels except for the CAN channel connected to the first network node.

With reference to the third aspect, in certain implementations of the third aspect, the instructions, when executed by the processor, cause the communication apparatus to perform the steps of: and when detecting that a third CAN channel in the multi-channel CAN channels has a fault, controlling the multi-channel selector to switch the CAN channel connected with a third network node from the third CAN channel to a second backup CAN channel, wherein the second backup CAN channel and the first backup CAN channel are different CAN channels.

With reference to the third aspect, in certain implementations of the third aspect, the instructions, when executed by the processor, cause the communication apparatus to perform the steps of: when detecting that a fourth CAN channel in the plurality of CAN channels has a fault, determining the priority of the first CAN channel, the priority of the third CAN channel and the priority of the fourth CAN channel; when the priority of the fourth CAN channel is greater than that of the first CAN channel and the priority of the first CAN channel is greater than that of a third CAN channel, controlling the multiplexer to disconnect the third network node from the second backup CAN channel and switch the CAN channel connected with the fourth network node from the fourth CAN channel to the second backup CAN channel; or when the priority of the fourth CAN channel is greater than that of the first CAN channel and the priority of the first CAN channel is less than that of the third CAN channel, controlling the multiplexer to disconnect the first network node from the first backup CAN channel and switch the CAN channel connected with the fourth network node from the fourth CAN channel to the first backup CAN channel.

In a fourth aspect, a communication apparatus is provided, including: a memory to store instructions; a processor for reading the instructions, which when executed by the processor, cause the communication device to perform the steps of: the multi-path CAN channel is respectively connected with a plurality of network nodes; when the CAN channels in the plurality of paths of CAN channels are detected to have faults, determining the priorities of the CAN channels; and controlling a multiplexer to respectively switch the two CAN channels with high priority in the at least two CAN channels to the two backup CAN channels.

In a fifth aspect, a chip is provided, which includes a processor and a communication interface, wherein the communication interface is configured to receive a signal and transmit the signal to the processor, and the processor processes the signal, so that the method for CAN communication redundancy as described in the first aspect and any possible implementation manner thereof is performed.

In a sixth aspect, a chip is provided, the chip comprising a processor and a communication interface for receiving a signal and transmitting the signal to the processor, the processor processing the signal such that the method of CAN communication redundancy as described in the second aspect above is performed.

In a seventh aspect, a computer-readable storage medium is provided, in which computer instructions are stored, and when the computer instructions are executed on a computer, the method for CAN communication redundancy as described in the first aspect and any one of its possible implementations is executed.

In an eighth aspect, there is provided a computer readable storage medium having stored therein computer instructions which, when run on a computer, cause the method of CAN communication redundancy as described in the second aspect above to be performed.

In a ninth aspect, there is provided a computer program product comprising computer instructions which, when run on a computer, cause a method of CAN communication redundancy as described in the first aspect and any one of its possible implementations to be performed.

A tenth aspect provides a computer program product comprising computer instructions which, when run on a computer, cause the method of CAN communication redundancy as described in the second aspect above to be performed.

Drawings

Fig. 1 is a schematic diagram of a CAN communication system architecture provided in an embodiment of the present application.

Fig. 2 is a schematic diagram of another CAN communication system architecture provided in the embodiment of the present application.

Fig. 3 is a schematic diagram of another CAN communication system architecture provided in the embodiment of the present application.

Fig. 4 is a schematic flowchart of a method for CAN communication redundancy according to an embodiment of the present application.

Fig. 5 is a schematic flowchart of another method for CAN communication redundancy according to an embodiment of the present application.

Detailed Description

The technical solution in the present application will be described below with reference to the accompanying drawings.

The technical scheme of the embodiment of the application can be applied to an in-vehicle communication system of the automobile.

As shown in fig. 1, the

external network nodes

100a and 100b communicate with a communication device 100, the communication device 100 may include a Micro Control Unit (MCU) 110, the MCU 110 may include a plurality of CAN controllers therein, and the communication device 100 may further include a plurality of CAN transceivers.

One CAN channel CAN comprise a CAN transceiver and a CAN controller. Referring to fig. 1, external network node 110a is connected via bus 101a to a CAN channel that includes CAN transceiver 102a and CAN controller 103a. When receiving data, the CAN transceiver 102a receives data from the bus and transmits the data to the CAN controller 103a; when transmitting data, the CAN transceiver 102a receives the coded signal transmitted by the CAN controller 103a, converts the coded signal into a differential signal, and transmits the differential signal to the network node 100a through the bus 101 a.

For example, the

external network nodes

100a and 100b may be any functional unit or device that CAN be accessed through a CAN bus, such as an engine control unit, an electric power steering control unit, and an air conditioning control unit.

In order to ensure the stability of the CAN communication system, the CAN communication is designed redundantly, referring to fig. 1, the communication device 100 designs a backup channel a for the external network node 100a, where the backup channel a includes a CAN transceiver 104a and a CAN controller 105a, the external network node 100a is connected to the backup channel a through a bus 106a, and when the CAN channel connected to the external network node 100a normally fails, the external network node 100a CAN be switched to the backup channel a.

It should be understood that in the embodiment of the present application, one CAN controller corresponds to one CAN transceiver.

Alternatively, one CAN controller may correspond to a plurality of CAN transceivers, and when a CAN channel fails, the CAN transceiver may fail, the CAN controller may fail, or the bus may fail, etc.

For the external network node B, the design of the backup channel B is also carried out, and when the CAN channel accessed by the external network node B fails, the backup channel B CAN be switched to, so that the reliability of network communication in the vehicle CAN be improved.

The external network node in fig. 1 is respectively connected to the two CAN channels through two buses, and in some embodiments, the external network node may also be connected to the two CAN channels through one bus.

It CAN be seen that, for each external network node, the communication device 100 performs a backup design on the CAN channel thereof, and although the reliability of the in-vehicle network communication CAN be improved, when there are many external network nodes in the vehicle, the in-vehicle network topology becomes complicated, the wiring harness deployment thereof is also very complicated, and in addition, the design of the backup channel is performed for each network node, which further increases the communication cost.

In view of this, the embodiment of the present application provides a method and a communication device for CAN communication redundancy, and the technical scheme CAN reduce the cost of an in-vehicle communication system and the complexity of an in-vehicle wiring harness structure while ensuring reliable in-vehicle communication.

The method and communication apparatus for CAN communication redundancy in the embodiment of the present application will be described below with reference to fig. 2 to 5.

As shown in fig. 2, the communication device 200 may include an MCU210, a plurality of CAN transceivers, and a multiplexer 230, the MCU210 may include a plurality of CAN controllers therein, and the multiplexer 230 may include a selector 231 and a plurality of bidirectional switches, each bidirectional switch corresponding to one external network node.

Alternatively, the CAN controller may also exist as a separate device without being in the MCU210, which is not limited in the embodiment of the present application.

Referring to fig. 2, an external network node a is connected to a bidirectional switch A0 through a bus, and A0 is connected to an access point A1 of a CAN transceiver 221 so that the external network node a is connected into a CAN channel through the bidirectional switch A0. When the CAN channel a to which the external network node a is connected fails, the bidirectional switch A0 is disconnected from A1 and connected to the access point A2 of the CAN transceiver 225 in the backup channel, so that the external network node CAN be connected to the CAN backup channel.

Specifically, when the MCU210 detects a failure of the CAN transceiver 221 or the CAN controller 211, the MCU210 initializes the backup channel and sets the receiving and sending of the backup channel data as a full mirror image of the CAN channel a connected to the external network node a; after the initialization of the backup channel is completed, the MCU210 sends a switching indication message to the selector 231 in the multiplexer 230; after receiving the switching instruction information, the selector 231 controls the bidirectional switch A0 to disconnect from the access point A1 of the CAN transceiver 221 in the CAN channel a and connect A0 to the access point A2 of the CAN transceiver 225 of the backup channel, thereby completing the switching from the failed channel to the backup channel.

Likewise, the external network node B is connected to the bidirectional switch B0 through a bus, and B0 is connected to the access point B1 of the CAN transceiver 222, so that the external network node B is connected into the CAN channel through the bidirectional switch B0. When the CAN channel to which the external network node B is connected fails, the bidirectional switch B0 is disconnected from B1 and connected to the access point B2 of the CAN transceiver 225 in the backup channel, so that the external network node CAN be connected to the CAN backup channel.

Specifically, when the MCU210 detects a failure of the CAN transceiver 222 or the CAN controller 214, the MCU210 initializes the backup channel and sets the reception and transmission of the backup channel data as a full mirror image of the CAN channel B connected to the external network node B; after the initialization of the backup channel is completed, the MCU210 sends a switching indication message to the selector 231 in the multiplexer 230; after receiving the switching instruction information, the selector 231 controls the bidirectional switch B0 to disconnect from the access point B1 of the CAN transceiver 222 in the CAN channel B and connect B0 to the access point B2 of the CAN transceiver 225 in the backup channel, thereby completing the switching from the failed channel to the backup channel.

For the external network node C and the external network node D, the description of the external network node a and the external network node B may be referred to, and details are not repeated for brevity.

In the embodiment of the present application, a backup channel is designed for a plurality of external communication nodes, the backup channel includes a CAN transceiver 225 and a CAN controller 213, the CAN transceiver 225 has four access points A2, B2, C2, and D2, which respectively correspond to four external network nodes, and when a CAN channel connected to one of the four external network nodes fails, the switching from the failed CAN channel to the backup channel CAN be completed through a bidirectional switch in the multiplexer.

It should be understood that, in the embodiment of the present application, four external network nodes are taken as an example for illustration, but this should not limit the present application at all, and in practical applications, the number of the external network nodes may not be specifically limited.

The above describes a case where the CAN channel to which one of the plurality of external network nodes is connected fails, and in some examples, it may happen that the CAN channel to which the plurality of network nodes are connected fails.

Possible fault situations of the CAN channel are:

the first situation is as follows:

and under the condition that the CAN channel corresponding to one network node is detected to be in fault and the CAN channel corresponding to the network node is switched to the backup channel, the CAN channel corresponding to the other network node is detected to be in fault.

For example, when the CAN channel corresponding to the external network node a fails (e.g., the CAN transceiver 211 fails), the MACU210 sends a switching indication message to the multiplexer, controls the bidirectional switch A0 to be disconnected from the switch A1, and connects the switch A0 to the switch A2, at this time, the external network node a is already connected to the backup channel, and in this case, the MCU210 detects that the CAN transceiver 222 fails again.

Case two:

and simultaneously detecting that the CAN channels corresponding to the multi-path network nodes have faults.

For example, when the CAN controller 211 and the CAN controller 214 fail, the CAN channel a and the CAN channel B corresponding to the CAN controller may fail.

For the possible failure situation of the CAN channels, in the embodiment of the present application, when the communication system is initially designed, the priority of each path of the CAN channel is formulated according to the importance of data transmitted in each path of the CAN channel, and when a plurality of CAN channels fail, the CAN channel with a high priority is preferentially switched to the backup channel according to the priority of each path of the CAN channel.

For case one above:

because the priority sequence of each path of CAN channel is already established when the communication system is initially designed, the priority of the CAN channel corresponding to the network node which is currently connected with the backup channel and the later detected priority of the CAN channel corresponding to the other network node CAN be judged at the moment. If the priority of the CAN channel corresponding to the network node which is currently connected with the backup channel is higher than the later detected priority of the CAN channel corresponding to the other network node, continuing to keep the current state; if the priority of the CAN channel corresponding to the network node which is currently connected with the backup channel is smaller than the priority of the CAN channel corresponding to the other detected network node, disconnecting the network node which is currently connected with the backup channel from the backup channel, and connecting the other detected network node to the backup channel.

For example, a CAN channel a to which the external network node a is connected fails, and the network node a is already connected to the backup channel, and at this time, it is detected that a CAN channel B corresponding to the external network node B fails. If the priority of the CAN channel A is higher than that of the CAN channel B, the current state is kept, and if the priority of the CAN channel A is lower than that of the CAN channel B, the connection between the external network node A and the backup channel is disconnected, and the external network node B is connected to the backup channel.

For case two above:

when the multiple CAN channels are detected to have faults, the external network node corresponding to the CAN channel with the highest priority in the multiple faulty CAN channels CAN be connected to the backup channel so as to complete the switching from the faulty CAN channel to the backup channel.

For example, it is detected that the CAN channel a and the CAN channel B have a fault at the same time, and if the priority of the CAN channel a is greater than that of the CAN channel B, the external network node corresponding to the CAN channel a is connected to the backup channel. If the data transmitted in the CAN channel a is the data of the vehicle engine control unit and the data transmitted in the CAN channel B is the data for adjusting the air conditioner in the vehicle, the data of the vehicle engine control unit is obviously more important than the data for adjusting the air conditioner in the vehicle.

Based on the embodiment of the application, a plurality of external network nodes are respectively connected to a plurality of CAN channels through the bidirectional switches in the multiplexer, one path of backup channel is designed, and when the CAN channel corresponding to one of the external network nodes is detected to have a fault, the switching from the fault CAN channel to the backup channel CAN be realized by controlling the disconnection and connection of the bidirectional switches. The technical scheme can not only ensure the reliability of the communication in the vehicle, but also reduce the cost of the communication system in the vehicle and the complexity of the wiring harness structure in the vehicle.

Further, when the two CAN channels are detected to have faults, the CAN channel with the high priority is switched to the backup channel, so that the communication reliability of important data is guaranteed.

The above describes a situation in which one backup channel is designed in the CAN communication system, and the following describes a situation in which two backup channels are designed in the CAN communication system with reference to fig. 3.

As shown in fig. 3, the communication device 300 may include an MCU210, a plurality of CAN transceivers, and a multiplexer 230, and the MCU210 may include a plurality of CAN controllers therein. The multiplexer 230 may include a selector 231 and a plurality of switches, each corresponding to an external network node.

Different from the communication apparatus 200, two backup channels are designed in the communication apparatus 300, which are respectively the backup channel a including the CAN controller 213 and the CAN transceiver 225, and the backup channel b including the CAN controller 216 and the CAN transceiver 226.

Referring to fig. 3, the CAN transceiver 225 in the backup channel a has four access points A2, B2, C2, and D2, respectively, and the CAN transceiver 226 in the backup channel B has four access points A3, B3, C3, and D3, respectively, corresponding to four external network nodes, respectively.

In case the communication device 3 has two backup paths, possible failure situations are:

the first situation is as follows:

and detecting that one CAN channel has a fault.

Case two:

and detecting that the two CAN channels have faults.

Case three:

and simultaneously detects that more than two CAN channels have faults.

Case four:

and detecting that the two CAN channels have faults, and detecting that the one CAN channel has faults under the condition that the network nodes corresponding to the two faulty CAN channels are connected to the two backup channels respectively.

For situation one above:

because the communication system is provided with two CAN backup channels, when one of the normally used CAN channels is detected to have a fault, the network node corresponding to the fault CAN channel CAN be connected to one of the two backup channels.

Illustratively, the order in which the two backup tunnels are used may be set in the system. Or, the sequence of the two backup channels is not limited, and one of the two backup channels is randomly selected when in use.

Taking the external network node a as an example, under a normal condition, the external network node a is connected to the access point A1 of the CAN transceiver 221 by default through the switch A0, and at a certain time, when the MCU210 detects that the CAN channel a connected to the external network node a has a fault, the switch A0 may be disconnected from the switch A1, and the switch A0 may be connected to the point A2 or the point A3, so that the CAN channel connected to the external network node may be switched from the faulty CAN channel a to the backup channel.

For example, when the CAN channel a connected to the external network node a fails, the switch A0 is disconnected from the switch A1 and connected to the switch A2, and then the CAN channel connected to the external network node is the backup channel a.

For case two above:

because the communication system is provided with two CAN backup channels, when the two CAN backup channels are detected to have faults, network nodes corresponding to the two faulty CAN channels CAN be respectively connected to the two backup channels.

In a possible implementation manner, the two CAN backup channels fail successively, for example, when the external network node a is already connected to one backup channel, the MCU210 detects that the CAN channel B connected to the network node B fails, and connects the network node B to the other backup channel.

In another possible implementation manner, if the two CAN backup channels fail at the same time, the network nodes corresponding to the two failed CAN channels are connected to the two backup channels, respectively.

For case three above:

when the communication system is initially designed, the priority of each path of CAN channel CAN be formulated according to the importance of data transmitted in each path of CAN channel, and when more than two paths of CAN channels are detected to have faults, the network nodes corresponding to the two paths of fault CAN channels with large priority CAN be selected to be connected to the two paths of backup CAN channels according to the priority of the more than two paths of fault CAN channels.

For case four above:

when the communication system is initially designed, the priority of each CAN channel is formulated according to the importance of data transmitted in each CAN channel, and when the two CAN channels are detected to have faults, the network nodes corresponding to the two failed CAN channels are respectively connected to two backup channels, and if the CAN channels are detected to have faults, whether the current state is kept or the network nodes corresponding to the detected failed CAN channels are connected to one backup channel CAN be determined through the priority sequence of the three failed CAN channels.

For example, if the CAN channels a and B connected by default to the network nodes a and B have a fault, and the network nodes a and B have also been connected to two backup channels, respectively, for example, the network node a is connected to the backup channel a, and the network node B is connected to the backup channel B, at this time, the MCU210 detects that the CAN channel C connected by default to the network node C has a fault, and the MCU210 may make a decision according to the priority of the CAN channels a, B and C.

And if the priority of the CAN channel C is smaller than the priorities of the CAN channel A and the CAN channel B, keeping the current state.

If the priority of the CAN channel C is greater than that of the CAN channel A and the priority of the CAN channel A is greater than that of the CAN channel B, disconnecting the network node B from the backup channel B and connecting the network node C to the backup channel B.

If the priority of the CAN channel C is greater than that of the CAN channel A and the priority of the CAN channel A is less than that of the CAN channel B, disconnecting the network node A from the backup channel a and connecting the network node C to the backup channel a.

Based on this application embodiment, a plurality of external network nodes are connected to a plurality of CAN passageway respectively through the switch in the multiplexer to two way backup channels have been designed, when detecting that one of them or two external network nodes correspond to the CAN passageway breaks down, the switching of trouble CAN passageway to backup channel is realized to disconnection and connection of accessible control switch. The technical scheme can not only ensure the reliability of the communication in the vehicle, but also reduce the cost of the communication system in the vehicle and the complexity of the wiring harness structure in the vehicle.

Furthermore, when more than two CAN channels are detected to have faults, the two CAN channels with high priority are switched to the two backup channels, so that the communication reliability of important data is guaranteed.

Fig. 4 is a schematic flowchart of a method for CAN redundant communication according to an embodiment of the present disclosure. As shown in fig. 4, the method may include steps 410 through 420.

And 410, establishing connection with a plurality of network nodes by a plurality of CAN channels respectively.

Each path of CAN channel CAN comprise a CAN controller and a CAN transceiver, the multiple paths of CAN channels are respectively connected with the multiple network nodes, and the multiple network nodes CAN be understood to be respectively communicated with the CAN transceivers in the multiple paths of CAN channels through buses.

For example, the CAN transceiver receives data transmitted by the network node through the bus and transmits the data to the CAN controller.

The network node may be an engine control unit, an electric power steering control unit, an air conditioning control unit, etc.

And 420, when detecting that a first CAN channel in the plurality of CAN channels has a fault, controlling the multiplexer to switch the CAN channel connected with the first network node to a first backup CAN channel, wherein the first CAN channel comprises the CAN channel connected with the first network node.

The first CAN channel may include one CAN channel or a plurality of CAN channels.

The multiplexer may include a plurality of bidirectional switches, each bidirectional switch corresponds to one of the CAN channels, each bidirectional switch is connected to one of the CAN channels in normal communication by default in a normal case, and another access point to which each bidirectional switch may be connected is an access point of the first backup CAN channel. When the CAN channel connected with the first network node fails, the multiplexer CAN be controlled to switch the CAN channel connected with the first network node to the first backup CAN channel.

Based on the embodiment of the application, a backup channel is designed for a plurality of CAN channels, and when the CAN channel connected with the first network node fails, the multiplexer CAN be controlled to switch the CAN channel connected with the first network node to the first backup CAN channel. According to the technical scheme, the backup of multiple CAN channels CAN be realized through one backup CAN channel, so that the reliability of communication in the vehicle CAN be ensured, and the cost of a communication system in the vehicle and the complexity of a wiring harness structure in the vehicle CAN be reduced.

Optionally, the multiplexer includes a plurality of bidirectional switches, the plurality of bidirectional switches correspond to the plurality of network nodes one to one, and when it is detected that a first CAN channel of the plurality of CAN channels has a fault, the controlling the multiplexer switches the CAN channel connected to the first network node to a first backup CAN channel includes: and controlling the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first CAN channel and connect the bidirectional switch to the first backup CAN channel.

In this embodiment, the CAN channel connected to the first network node is the first CAN channel.

Illustratively, referring to fig. 2, the multiplexer 230 includes a plurality of bidirectional switches A0, B0, C0, and D0. The first network node may be a network node a, the CAN channel connected to the network node a is a CAN channel a, and when it is detected that the CAN channel a has a fault, the multiplexer 230 is controlled to disconnect the bidirectional switch corresponding to the network node a from the CAN channel a and connect the bidirectional switch to the backup channel.

Optionally, the controlling the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first CAN channel and connect the bidirectional switch to the first backup CAN channel includes: and sending first switching indication information to the multiplexer, wherein the first switching indication information is used for indicating the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first CAN channel and connect the bidirectional switch to the first backup CAN channel.

For example, referring to fig. 2, the first backup CAN channel may be the backup channel in fig. 2, and includes a CAN controller 213 and a CAN transceiver 225, the first network node may be a network node a, when it is detected that the CAN channel a connected to the network node a has a fault, the MCU210 sends a first switching indication message to the multiplexer, and after receiving the first switching indication message, the selector 231 in the multiplexer 230 controls the switch A0 to disconnect from the A1 and connect to the A2, so as to complete the switching from the faulty CAN channel to the first backup CAN channel.

Optionally, the method may further comprise steps 430 to 440:

430, when detecting that a second CAN channel in the plurality of CAN channels has a fault, determining the priority of the first CAN channel and the second CAN channel.

For example, referring to fig. 2, the first CAN channel may be a CAN channel a to which a network node a is connected, and the second CAN channel may be a CAN channel B to which a network node B is connected. When the network node A firstly breaks down and the CAN channel A is switched to the first backup channel, the CAN channel B connected with the network node B is detected to break down, the priority of the CAN channel A and the priority of the CAN channel B CAN be judged at the moment, and the switching strategy is determined according to the priority of the CAN channel A and the priority of the CAN channel B.

440, when the priority of the second CAN channel is greater than the priority of the first CAN channel, controlling the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first backup CAN channel, disconnect the bidirectional switch corresponding to the second network node from the second CAN channel, and connect the bidirectional switch corresponding to the second network node to the first backup CAN channel.

Illustratively, as stated in step 430, when the priority of the CAN channel B is greater than the priority of the CAN channel a, it is determined that the CAN channel B is switched to the first backup channel, the multiplexer is controlled to disconnect the bidirectional switch A0 corresponding to the network node a from the point A2, disconnect the bidirectional switch B0 corresponding to the network node B from the point B1, and connect the B0 to the point B2. Thus, the connection of the network node B to the backup tunnel is completed.

Specifically, switching instruction information may be sent to the multiplexer to instruct it to perform the above-described switching operation.

Optionally, when the priority of the second CAN channel is less than the priority of the first CAN channel, the current state may be maintained, i.e. the connection of the first network node with the first backup channel is maintained.

Optionally, the determining the priority of the first CAN channel and the second CAN channel includes:

and determining the priority of the first CAN channel and the second CAN channel according to the data transmitted by the first CAN channel and the second CAN channel.

For example, when the communication system initially relates to the vehicle, the priority of each CAN channel CAN be set according to the importance of the data to be transmitted by each CAN channel, for example, the priority of the CAN channel for transmitting the vehicle engine control data is higher than the priority of the CAN channel for transmitting and adjusting the vehicle air conditioner data.

According to the technical scheme, the CAN channel with high priority is switched to the backup channel, so that the communication reliability of important data is guaranteed.

Optionally, the controlling the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first backup CAN channel, disconnect the bidirectional switch corresponding to the second network node from the second backup CAN channel, and connect the bidirectional switch corresponding to the second network node to the first backup CAN channel includes:

and sending second switching indication information to a multiplexer, wherein the second switching indication information is used for indicating the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first backup CAN channel, disconnect the bidirectional switch corresponding to the second network node from the second CAN channel, and connect the bidirectional switch corresponding to the second network node to the first backup CAN channel.

In this embodiment, when it is determined that the second network node is connected to the first backup tunnel, second switching indication information may be sent to the multiplexer to indicate it to switch.

Optionally, the first CAN channel includes at least two CAN channels, a priority of the CAN channel connected to the first network node is higher than a priority of the CAN channel connected to the third network node, and the CAN channel connected to the third network node is a channel of the at least two CAN channels other than the CAN channel connected to the first network node.

In this embodiment, the first CAN channel may include multiple CAN channels. For example, the first CAN channel includes two CAN channels, that is, if a failure of the two CAN channels is detected, the CAN channel connected to the first network node with the higher priority is switched to the first backup channel, thereby facilitating to ensure the communication reliability of important data.

Optionally, when it is detected that a third CAN channel of the multiple CAN channels has a fault, the multiplexer is controlled to switch the third CAN channel connected to a third network node to a second backup CAN channel, where the second backup CAN channel is a different CAN channel from the first backup CAN channel.

In this embodiment, the communication system has two backup tunnels. For example, referring to fig. 3, the first network node may be a network node a, the third network node may be a network node B, and after the CAN channel a connected to the first network node is switched to the first backup CAN channel, and a failure of the CAN channel B corresponding to the network node B is detected, the CAN channel connected to the network node B may be switched to the second backup CAN channel.

In the case of two backup CAN channels, the order of use of the two backup CAN channels may be set, for example, when only one CAN channel fails, the first backup CAN channel is preferentially used.

Optionally, when a fourth CAN channel of the multiple CAN channels is detected to have a fault, determining priorities of the first CAN channel, the third CAN channel and the fourth CAN channel;

when the priority of the fourth CAN channel is greater than that of the first CAN channel and the priority of the first CAN channel is greater than that of a third CAN channel, controlling the multiplexer to disconnect the third network node from the second backup CAN channel and switch the CAN channel connected with the fourth network node from the fourth CAN channel to the second backup CAN channel; or

And when the priority of the fourth CAN channel is greater than that of the first CAN channel and the priority of the first CAN channel is less than or equal to that of the third CAN channel, controlling the multiplexer to disconnect the first network node from the first backup CAN channel and switch the CAN channel connected with the fourth network node from the fourth CAN channel to the first backup CAN channel.

Illustratively, referring to fig. 3, the first network node may be a network node a, the first CAN channel is a CAN channel a to which the network node a is connected, the third network node may be a network node B, the second CAN channel is a CAN channel B to which the network node B is connected, the fourth network node may be a network node C, and the third CAN channel is a CAN channel C to which the network node C is connected. When the CAN channels originally connected with the network node A and the network node B are in fault and are respectively switched to the two backup CAN channels, the CAN channel C connected with the network node C is detected to be in fault, and at the moment, switching decision CAN be carried out according to the priority levels of the CAN channel A, the CAN channel B and the CAN channel C.

For example, when the priority of the CAN channel C is greater than that of the CAN channel a and the priority of the CAN channel a is greater than that of the CAN channel B, the multiplexer is controlled to disconnect the switch B0 of the network node B from the switch B3, disconnect the switch C0 corresponding to the network node C from the switch C1, and connect the switch C0 to the switch C3, so that the network node C CAN be connected to the backup CAN channel.

When the priority of the CAN channel C is greater than that of the CAN channel A and the priority of the CAN channel A is less than that of the CAN channel B, the multiplexer is controlled to disconnect the switch A0 of the network node A from the switch A2, disconnect the switch C0 corresponding to the network node C from the switch C1 and connect the switch C0 to the switch C2, so that the network node C CAN be connected to the backup CAN channel.

And when the priority of the CAN channel C is smaller than the priority of the CAN channel A and the priority of the CAN channel B, keeping the current state, namely continuously keeping the connection between the network node A and the backup channel and the connection between the network node B and the backup channel.

The technical scheme is favorable for ensuring the communication reliability of important data.

Fig. 5 is a schematic flowchart of another method for CAN redundant communication according to an embodiment of the present application.

As shown in fig. 5, the method may include steps 510 to 530.

And 510, establishing connection between the multiple CAN channels and the multiple network nodes respectively.

This step 510 may refer to the related description in step 410, and is not described again for brevity.

And 520, when the condition that at least two CAN channels in the plurality of CAN channels have faults is detected at the same time, determining the priority of the at least two CAN channels.

When the multi-path CAN channel is detected to have faults, switching decision CAN be carried out according to the priority of the multi-path CAN channel.

And 530, controlling a multiplexer to respectively switch the two CAN channels with high priority levels in the at least two CAN channels to the two backup CAN channels.

Embodiments of the present application further provide a communication apparatus, including a processing unit, configured to execute the method for CAN communication redundancy as described in any of the above.

The embodiment of the present application further provides a communication apparatus, including a memory, configured to store instructions; a processor for reading the instructions, which when executed by the processor, cause the communication device to perform a method of CAN communication redundancy as described in any one of the above.

Embodiments of the present application further provide a chip, where the chip includes a processor and a communication interface, where the communication interface is configured to receive a signal and transmit the signal to the processor, and the processor processes the signal, so that the method for CAN communication redundancy as described in any of the above is performed.

Embodiments of the present application also provide a computer-readable storage medium comprising computer instructions that, when executed on a communication device, cause the communication device to perform a method of CAN communication redundancy as described in any of the above.

Embodiments of the present application also provide a computer program product comprising computer instructions that, when executed on a computer, cause a method of CAN communication redundancy as described in any of the above to be performed.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one type of logical functional division, and other divisions may be realized in practice, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one position, or may be distributed on multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a read-only memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method of CAN communication redundancy, comprising:

the multi-path CAN channel is respectively connected with a plurality of network nodes;

and when detecting that a first CAN channel in the plurality of CAN channels has a fault, controlling a multiplexer to switch the CAN channel connected with the first network node to a first backup CAN channel, wherein the first CAN channel comprises the CAN channel connected with the first network node.

2. The method of claim 1, wherein the multiplexer comprises a plurality of bidirectional switches, the plurality of bidirectional switches are in one-to-one correspondence with the plurality of network nodes, and wherein controlling the multiplexer to switch the CAN channel connected to the first network node to the first backup CAN channel when a failure of a first CAN channel of the plurality of CAN channels is detected comprises:

and controlling the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first CAN channel and connect the bidirectional switch to the first backup CAN channel.

3. The method of claim 2, wherein said controlling the multiplexer to disconnect the bi-directional switch corresponding to the first network node from the first CAN channel and to connect to the first backup CAN channel comprises:

and sending first switching indication information to the multiplexer, wherein the first switching indication information is used for indicating the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first CAN channel and connect the bidirectional switch to the first backup CAN channel.

4. The method according to any one of claims 1-3, further comprising:

when detecting that a second CAN channel in the plurality of CAN channels has a fault, determining the priority of the first CAN channel and the priority of the second CAN channel;

and when the priority of the second CAN channel is greater than that of the first CAN channel, controlling the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first backup CAN channel, disconnect the bidirectional switch corresponding to the second network node from the second CAN channel, and connect the bidirectional switch corresponding to the second network node to the first backup CAN channel.

5. The method of claim 4, wherein the determining the priority of the first CAN channel and the second CAN channel comprises:

6. The method of claim 4 or 5, wherein said controlling the multiplexer to disconnect the corresponding bidirectional switch of the first network node from the first backup CAN channel, to disconnect the corresponding bidirectional switch of the second network node from the second CAN channel, and to connect the corresponding bidirectional switch of the second network node to the first backup CAN channel comprises:

7. The method of claim 1 wherein the first CAN channel comprises at least two CAN channels, wherein the CAN channel connected to the first network node has a priority greater than the priority of the CAN channel connected to a third network node, and wherein the CAN channel connected to the third network node is one of the at least two CAN channels other than the CAN channel connected to the first network node.

8. The method of claim 1, further comprising:

and when detecting that a third CAN channel in the multi-channel CAN channels has a fault, controlling the multi-channel selector to switch the CAN channel connected with a third network node from the third CAN channel to a second backup CAN channel, wherein the second backup CAN channel and the first backup CAN channel are different CAN channels.

9. The method of claim 8, further comprising:

when detecting that a fourth CAN channel in the plurality of CAN channels has a fault, determining the priority of the first CAN channel, the priority of the third CAN channel and the priority of the fourth CAN channel;

And when the priority of the fourth CAN channel is greater than that of the first CAN channel and the priority of the first CAN channel is less than that of the third CAN channel, controlling the multiplexer to disconnect the first network node from the first backup CAN channel and switch the CAN channel connected with the fourth network node from the fourth CAN channel to the first backup CAN channel.

10. A method of CAN communication redundancy, comprising:

when the CAN channels in the plurality of paths of CAN channels are detected to have faults, determining the priorities of the CAN channels;

and controlling a multiplexer to respectively switch the two CAN channels with high priority in the at least two CAN channels to the two backup CAN channels.

11. A communications apparatus, comprising:

a memory to store instructions;

a processor for reading the instructions, which when executed by the processor, cause the communication device to perform the steps of:

and when detecting that a first CAN channel in the plurality of CAN channels has a fault, controlling a multiplexer to switch a CAN channel connected with a first network node to a first backup CAN channel, wherein the first CAN channel comprises a CAN channel connected with the first network node.

12. The apparatus of claim 11, wherein the multiplexer comprises a plurality of bidirectional switches, the plurality of bidirectional switches in one-to-one correspondence with the plurality of network nodes, and wherein the instructions, when executed by the processor, cause the communication apparatus to perform the steps of:

and controlling the multiplexer to disconnect the bidirectional switch corresponding to the first network node from the first CAN channel and connect the bidirectional switch corresponding to the first network node to the first backup CAN channel.

13. The apparatus of claim 12, wherein the instructions, when executed by the processor, cause the communication apparatus to perform the steps of:

14. The apparatus according to any of claims 11-13, wherein the instructions, when executed by the processor, cause the communication apparatus to perform the steps of:

when a second CAN channel in the plurality of CAN channels is detected to have a fault, determining the priority of the first CAN channel and the priority of the second CAN channel;

15. The apparatus of claim 14, wherein the instructions, when executed by the processor, cause the communication apparatus to perform the steps of:

16. The apparatus of claim 14, wherein the instructions, when executed by the processor, cause the communication apparatus to perform the steps of:

17. The apparatus of claim 11 wherein the first CAN channel comprises at least two CAN channels, wherein a CAN channel connected to the first network node has a priority greater than a CAN channel connected to a third network node, and wherein a CAN channel connected to the third network node is one of the at least two CAN channels other than the CAN channel connected to the first network node.

18. The apparatus of claim 11, wherein the instructions, when executed by the processor, cause the communication apparatus to perform the steps of:

19. The apparatus of claim 18, wherein the instructions, when executed by the processor, cause the communication apparatus to perform the steps of:

when the priority of the fourth CAN channel is greater than that of the first CAN channel and the priority of the first CAN channel is greater than that of a third CAN channel, controlling the multiplexer to disconnect the third network node from the second backup CAN channel and switch the CAN channel connected with the fourth network node from the fourth CAN channel to the second backup CAN channel; or alternatively

20. A communications apparatus, comprising:

a memory to store instructions;

and controlling a multiplexer to respectively switch the two CAN channels with high priority levels in the at least two CAN channels to the two backup CAN channels.

21. A computer readable storage medium comprising computer instructions stored therein which, when run on a computer, cause the method of CAN communication redundancy of any of claims 1-9 or 10 to be performed.