CN116248433A - CAN communication system, CAN communication method and working machine - Google Patents

Abstract

The invention relates to the field of engineering machinery, and provides a CAN communication system, a CAN communication method and an operation machine, wherein the CAN communication system comprises the following components: the controller comprises a plurality of controllers, a first switching device, a second switching device, a first trunk CAN line, a second trunk CAN line and branch CAN lines corresponding to the controllers; the plurality of controllers comprise an arbitration controller and a plurality of node controllers, wherein the arbitration controller is used for receiving respiratory signals sent by each node controller according to preset frequency, and sending switching signals to the first switching device and the second switching device when the respiratory signals are determined to meet line switching conditions; the first switching device and the second switching device control the first trunk CAN line or the second trunk CAN line to be switched to the access state based on the switching signal. The invention CAN effectively improve the stability and reliability of CAN communication.

Description

CAN communication system, CAN communication method and working machine

Technical Field

The invention relates to the technical field of engineering machinery, in particular to a CAN communication system, a CAN communication method and an operation machine.

Background

The CAN network is used as an information transmission and control mode capable of reducing the number of hard wires and enhancing the control precision, and has been greatly developed in the fields of engineering machinery, automobiles and the like, and has wide application. Taking engineering machinery as an example, the CAN network CAN be connected with an entire vehicle controller, an engine controller, a display controller, an air conditioner, a power distribution module, a key panel, an electric control handle, an electric control pedal and other electric components, so that CAN wires are generally distributed at positions of a cab, a radiator chamber, a main pump chamber, a main valve cabin and the like. For convenient assembly, CAN wires are commonly subjected to wire doubling crimping and even break the operation of crimping terminals when being arranged, so that the stability of CAN wire transmission is influenced. If the CAN network fails in the running process of the vehicle, the vehicle is caused to run abnormally if the CAN network is light, and the vehicle is out of control if the CAN network is heavy, so that the property and personal safety are endangered.

In the related art, a two-way CAN line is generally used to connect each controller for CAN communication, and all controllers support a two-way CAN channel and fault monitoring. And when a certain controller monitors that the corresponding CAN line has communication faults, all other controllers are requested to be switched to another CAN line for communication, so that communication interruption caused by CAN network faults is avoided. However, this method requires that all controllers support a two-way CAN channel, and for controllers such as an air conditioner controller, a key panel controller, and the like, which only include one way CAN channel, stability and reliability of communication cannot be ensured.

Disclosure of Invention

In view of the foregoing problems in the related art, the present invention provides a CAN communication system, a method, and a working machine.

The invention provides a CAN communication system, comprising: the controller comprises a plurality of controllers, a first switching device, a second switching device, a first trunk CAN line, a second trunk CAN line and branch CAN lines corresponding to the controllers; the first trunk CAN line and the second trunk CAN line are connected in parallel between the first switching device and the second switching device; the controllers are connected with the first trunk CAN line and the second trunk CAN line through the corresponding branch CAN lines; the plurality of controllers comprise an arbitration controller and a plurality of node controllers, and the arbitration controller is also connected with the first switching device and the second switching device;

The arbitration controller is used for receiving the breathing signals sent by each node controller according to the preset frequency, and sending switching signals to the first switching device and the second switching device when the breathing signals are determined to meet the line switching conditions;

the first switching device and the second switching device control the first trunk CAN line or the second trunk CAN line to be switched into an access state based on the switching signal.

According to the CAN communication system provided by the invention, the arbitration controller is particularly used for:

and if the respiratory signal sent by the target controller in each node controller is not received within the preset time, determining that the line switching condition is met, and if not, determining that the line switching condition is not met.

According to the CAN communication system provided by the invention, the arbitration controller is further used for:

and generating an alarm signal when the respiration signal sent by the node controller outside the target controller is not received within a preset time period and the respiration signal sent by the target controller is received.

The CAN communication system provided by the invention further comprises a display control device, wherein the display control device is connected with the arbitration controller;

The arbitration controller is further configured to generate status data of the first trunk CAN line or the second trunk CAN line based on the respiratory signal;

the arbitration controller is further configured to send at least one of the status data, the alert signal, and the switch signal to the display control device.

According to the CAN communication system provided by the invention, the branch CAN lines corresponding to the arbitration controller comprise a first branch CAN line and a second branch CAN line;

the arbitration controller is connected with the first trunk CAN line through the first branch CAN line and connected with the second trunk CAN line through the second branch CAN line.

According to the CAN communication system provided by the invention, the node controller comprises a first node controller and a second node controller;

the first node controller is connected with the first trunk CAN line and the second trunk CAN line through the corresponding branch CAN lines and the first switching device;

the second node controller is connected with the first trunk CAN line and the second trunk CAN line through the corresponding branch CAN line and the second switching device.

According to the CAN communication system provided by the invention, the first switching device comprises a first switch and a second switch which are arranged in an interlocking way, and a third switch and a fourth switch which are arranged in the interlocking way; the branch CAN line corresponding to the first node controller comprises a first positive CAN line and a first negative CAN line; the first positive CAN line is connected with the positive CAN line of the first trunk CAN line and the positive CAN line of the second trunk CAN line through the first switch and the second switch respectively; the first negative CAN line is connected with the negative CAN line of the first trunk CAN line and the negative CAN line of the second trunk CAN line through the third switch and the fourth switch respectively;

And/or the second switching device comprises a fifth switch and a sixth switch which are arranged in an interlocking way, and a seventh switch and an eighth switch which are arranged in an interlocking way; the branch CAN line corresponding to the second node controller comprises a second positive CAN line and a second negative CAN line; the second positive CAN line is connected with the positive CAN line of the first trunk CAN line and the positive CAN line of the second trunk CAN line through the fifth switch and the sixth switch respectively; the second negative CAN line is connected with the negative CAN line of the first trunk CAN line and the negative CAN line of the second trunk CAN line through the seventh switch and the eighth switch respectively.

According to the CAN communication system provided by the invention, the node controllers comprise at least one third node controller;

the branch CAN line corresponding to the third node controller comprises a third positive CAN line and a third negative CAN line;

one end of the third positive CAN line is connected with the corresponding third node controller, the other end of the third positive CAN line is connected with a first branch and a second branch which are arranged in parallel, the other end of the first branch is connected with the positive CAN line of the first trunk CAN line, and the other end of the second branch is connected with the positive CAN line of the second trunk CAN line;

One end of the third negative CAN line is connected with the corresponding third node controller, the other end of the third negative CAN line is connected with a third branch and a fourth branch which are arranged in parallel, the other end of the third branch is connected with the negative CAN line of the first trunk CAN line, and the other end of the fourth branch is connected with the negative CAN line of the second trunk CAN line.

The invention also provides a CAN communication method, which comprises the following steps:

receiving respiratory signals sent by each node controller according to preset frequency through an arbitration controller; the arbitration controllers and the node controllers are connected with the first trunk CAN line and the second trunk CAN line through corresponding branch CAN lines;

the arbitration controller sends a switching signal to the first switching device and the second switching device when determining that the line switching condition is met based on the respiratory signal; the first switching device and the second switching device control the first trunk CAN line or the second trunk CAN line to be switched into an access state based on the switching signal, and the first trunk CAN line and the second trunk CAN line are connected in parallel between the first switching device and the second switching device.

The invention also provides a working machine comprising a CAN communication system as described in any one of the above, or using a CAN communication method as described above.

According to the CAN communication system, the method and the operation machine, the arbitration controller, the plurality of node controllers, the first switching device, the second switching device and the first trunk CAN line and the second trunk CAN line which are connected in parallel between the first switching device and the second switching device are arranged, the arbitration controller is used for receiving the breathing signals sent by the node controllers according to the preset frequency, and sending the switching signals to the first switching device and the second switching device when the line switching conditions are met based on the breathing signals, so that the first trunk CAN line or the second trunk CAN line is controlled to be switched to an access state through the first switching device and the second switching device, communication CAN be carried out through the trunk CAN line switched to the access state in the first trunk CAN line and the second trunk CAN line, each node controller does not need to support a two-way CAN channel, fault monitoring is not needed, the stability and the reliability of CAN network are effectively ensured, and the safety of vehicle operation is further improved.

Meanwhile, when the circuit is switched, the structure of the whole CAN network is not changed, the requirement that the terminal resistor is arranged at two farthest ends CAN be still met, and the communication stability of the whole CAN network is further improved.

In addition, the invention only needs the arbitration controller to monitor faults, and each node controller only needs to send breathing signals according to preset frequency, so that the logic complexity of each node controller is greatly reduced, the risk of running errors of the node controllers is further reduced, and the running safety of vehicles is further improved.

Drawings

In order to more clearly illustrate the invention or the technical solutions of the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the invention, and other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a CAN communication system according to the invention;

FIG. 2 is a second schematic diagram of a CAN communication system according to the invention;

FIG. 3 is a third schematic diagram of the CAN communication system according to the invention;

FIG. 4 is a schematic diagram of a CAN communication system according to the invention;

FIG. 5 is a flow chart of the CAN communication method provided by the invention;

fig. 6 is a schematic structural diagram of an electronic device provided by the present invention;

reference numerals:

101: a first switching device; 102: a second switching device; 103: a first trunk CAN line; 104: a second trunk CAN line; 105: a branch CAN line; 106: an arbitration controller; 107: a node controller; 108: a first hard line; 201: a display control device; 202: arbitrating a CAN line; 203: a second hard line; 301: a first node controller; 302: a second node controller; 401: a first switch; 402: a second switch; 403: a third switch; 404: a fourth switch; 405: a first positive CAN line; 406: a first negative CAN line; 407: a first coil; 408: and a second coil.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is apparent that the described embodiments are some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The CAN communication system of the present invention is described below with reference to fig. 1 to 4. As shown in fig. 1, the CAN communication system of the present invention at least includes: a plurality of controllers, a first switching device 101, a second switching device 102, a first trunk CAN line 103, a second trunk CAN line 104, and a branch CAN line 105 corresponding to each controller; the first trunk CAN line 103 and the second trunk CAN line 104 are connected in parallel between the first switching device 101 and the second switching device 102; the controllers are connected with the first trunk CAN line 103 and the second trunk CAN line 104 through the corresponding branch CAN lines 105; the plurality of controllers includes an arbitration controller 106 and a plurality of node controllers 107, the arbitration controller 106 being further connected to the first switching device 101 and the second switching device 102;

the arbitration controller 106 is configured to receive a respiratory signal sent by each node controller 107 according to a preset frequency, and send a switching signal to the first switching device 101 and the second switching device 102 when it is determined that a line switching condition is met based on the respiratory signal;

the first switching device 101 and the second switching device 102 control the first trunk CAN line 103 or the second trunk CAN line 104 to switch to an access state based on the switching signal, and the trunk CAN line switched to the access state in the first trunk CAN line 103 and the second trunk CAN line 104 is used for completing communication between the plurality of controllers.

In this embodiment, the first trunk CAN line 103 may be a trunk CAN line used in a normal communication process of a vehicle, and the second trunk CAN line 104 may be a standby CAN line of the first trunk CAN line 103, for performing communication when the first trunk CAN line 103 fails, so as to avoid abnormal vehicle operation caused by the failure of the first trunk CAN line 103 in the vehicle operation process.

The first trunk CAN line 103 and the second trunk CAN line 104 are connected in parallel between the first switching device 101 and the second switching device 102, that is, two ends of the first trunk CAN line 103 (two farthest ends of the first trunk CAN line 103) are respectively connected with the first switching device 101 and the second switching device 102, and two ends of the second trunk CAN line 104 (two farthest ends of the second trunk CAN line 104) are also respectively connected with the first switching device 101 and the second switching device 102, so that switching of the first trunk CAN line 103 and the second trunk CAN line 104 CAN be controlled by the first switching device 101 and the second switching device 102, that is, a state when the whole vehicle CAN network is accessed. For example, when the first trunk CAN line 103 is controlled to switch to the access state, the second trunk CAN line 104 is controlled to be disconnected, and when the second trunk CAN line 104 is controlled to switch to the access state, the first trunk CAN line 103 is controlled to be disconnected, so that only one trunk CAN line of the first trunk CAN line 103 and the second trunk CAN line 104 is ensured to be in the access state at any time.

The first switching device 101 and the second switching device 102 may each include a plurality of switching devices, and the plurality of switching devices are controlled to switch in a linkage manner by a switching signal, so as to switch the first trunk CAN line 103 and the second trunk CAN line 104.

The controllers CAN be controllers which need to be communicated in the vehicle, any one of the controllers is connected with the first branch CAN line and the second branch CAN line through corresponding branch CAN lines 105, and each controller CAN communicate through a trunk CAN line in an access state in the first trunk CAN line 103 and the second trunk CAN line 104.

The plurality of controllers includes an arbitration controller 106 and a plurality of node controllers 107, the number of arbitration controllers 106 may be one, and the arbitration controller 106 may be electrically connected to the first switching device 101 and the second switching device 102 through a first hard wire 108 to transmit a switching signal to the first switching device 101 and the second switching device 102 when a line switching condition is satisfied. In which only one node controller 107 is illustrated in fig. 1. In addition, in this embodiment, the specific manner in which the arbitration controller 106 is in signal connection with the first trunk CAN line 103 and the second trunk CAN line 104, and the specific manner in which the node controller 107 is in signal connection with the first trunk CAN line 103 and the second trunk CAN line 104 are not particularly limited, and the connection manner in fig. 1 is only an alternative embodiment.

The respiration signal is a signal for indicating that the corresponding node controller 107 is in a power-on state, and may be a character or a character string of a preset type. Any of the plurality of node controllers 107 may send a respiration signal at a preset frequency, for example, the node controller 107 may send a respiration signal every 50 milliseconds.

The arbitration controller 106 obtains the breathing signal sent by each node controller 107 through the trunk CAN line and the corresponding branch CAN line 105 which are in the access state at the current moment, determines whether the line switching condition is met based on the breathing signal, and sends the switching signal to the first switching device 101 and the second switching device 102 when the line switching condition is met so as to control the first trunk CAN line 103 and the second trunk CAN line 104 to switch, so that the switching of the first trunk CAN line 103 and the second trunk CAN line 104 CAN be completed through the arbitration controller 106, the first switching device 101 and the second switching device 102, each node controller 107 does not need to support a two-way CAN channel, does not need to perform fault monitoring on a CAN network, and ensures the stability and reliability of CAN communication.

The specific manner in which the arbitration controller 106 determines whether the line switching condition is satisfied based on the respiratory signal may be determined according to actual requirements, for example, when no respiratory signal is received within a preset period of time, a trunk CAN line fault indicating that the current time is in an access state may be determined to satisfy the line switching condition; the line switching condition may also be determined to be satisfied when the respiration signal of the target controller in each node controller 107 is not received within the preset time period, otherwise, the line switching condition is determined not to be satisfied. It CAN be appreciated that when only the respiration signals of some of the node controllers 107 are received, it is determined that the branch CAN line 105 corresponding to the node controller 107 without the respiration signals has a fault, so that fault detection CAN be performed on the trunk CAN line and the branch CAN line 105 at the same time, and the abnormal running risk of the vehicle caused by the fault of the CAN network in the running process of the vehicle is further reduced.

As CAN be seen, in this embodiment, by setting the arbitration controller 106, the plurality of node controllers 107, the first switching device 101, the second switching device 102, and the first trunk CAN line 103 and the second trunk CAN line 104 connected in parallel between the first switching device 101 and the second switching device 102, and receiving the respiratory signal sent by each node controller 107 according to the preset frequency through the arbitration controller 106, and sending the switching signal to the first switching device 101 and the second switching device 102 when the line switching condition is determined to be met based on the respiratory signal, the first switching device 101 and the second switching device 102 are used for controlling the first trunk CAN line 103 or the second trunk CAN line 104 to switch to the access state, so that communication CAN be performed through the trunk CAN line 103 and the second trunk CAN line 104 switched to the access state, each node controller 107 does not need to support a two-way CAN channel, and also does not need to perform fault monitoring on the CAN network, stability and reliability of CAN communication are effectively ensured, and safety of vehicle running is further improved.

Meanwhile, in the prior art that two paths of CAN lines are connected with controllers, each path of CAN line is responsible for signal transmission of different controllers in normal communication, when one controller monitors that the corresponding CAN line has communication faults, all other controllers are required to be switched to the other path of CAN line for communication, so that the structure of the whole CAN network is changed in line switching, the requirement that terminal resistors are arranged at two farthest ends of a trunk CAN line cannot be met, and the instability of CAN communication is further increased.

In this embodiment, two furthest ends of the first trunk CAN line 103 may be respectively provided with a termination resistor, and two furthest ends of the second trunk CAN line 104 may also be respectively provided with a termination resistor, so that when it is detected that the first trunk CAN line 103 or the second trunk CAN line 104 fails to perform line switching, the structure of the whole vehicle CAN network will not change, and the requirement that the termination resistors are arranged at the two furthest ends of the trunk CAN line CAN still be met, thereby further improving the communication stability of the whole vehicle CAN network.

In addition, in the related art that adopts the two-way CAN line to connect each controller, each controller CAN be used as the arbitration controller 106, so that the logic complexity of the controller is increased, and the risk of the operation error of the controller is further increased due to the complexity. In this embodiment, only the arbitration controller 106 is needed to perform fault monitoring, and each node controller 107 only needs to send a respiratory signal according to a preset frequency, so that the logic complexity of each node controller 107 is greatly reduced, the risk of running errors of the node controllers 107 is further reduced, and the running safety of the vehicle is further improved.

In an exemplary embodiment, the arbitration controller 106 is specifically configured to:

If the respiratory signal sent by the target controller in each node controller 107 is not received within a preset time period, determining that the line switching condition is met, and if not, determining that the line switching condition is not met.

In this embodiment, the target controller in each node controller 107 may be the node controller 107 that plays a key role in the performance of the vehicle during operation, such as a whole vehicle controller, an engine controller, and the like. The preset time period may be set according to actual requirements, for example, may be set to 1 second.

If the arbitration controller 106 does not receive the respiratory signal sent by the target controller within the preset time, the condition of line switching is indicated to be satisfied, and if not, the condition of line switching is indicated not to be satisfied, so that fault monitoring and line switching CAN be effectively performed on the trunk CAN line while the running performance of the vehicle is ensured, and the running safety of the vehicle is further improved.

It CAN be understood that if the first trunk CAN line 103 is switched to the second trunk CAN line 104 and then the respiration signal sent by the target controller cannot be received within the preset time, the respiration signal CAN be switched back to the first trunk CAN line 103, if the line switching condition is met, it is indicated that both the first trunk CAN line 103 and the second trunk CAN line 104 have faults, or that the branch CAN line 105 corresponding to the target controller has faults, an alarm signal CAN be generated to remind related personnel of timely troubleshooting; if the line switching condition is not met after the first trunk CAN line 103 is switched back, communication is performed through the first trunk CAN line 103, and reliability of fault monitoring results is guaranteed.

In an exemplary embodiment, the arbitration controller 106 is further configured to:

and generating an alarm signal when the respiration signal sent by the node controller 107 outside the target controller is not received within a preset time period and the respiration signal sent by the target controller is received.

In this embodiment, if the arbitration controller 106 receives the respiration signal sent by the target controller within the preset time period, but does not receive the respiration signal sent by one or more node controllers 107 other than the target controller, it indicates that the corresponding branch CAN line 105 of the node controller 107 has a fault, and no line switching may be performed, so as to generate an alarm signal, so as to remind relevant personnel of timely troubleshooting, thereby implementing comprehensive monitoring on faults of the branch CAN line 105, the first trunk CAN line 103 and the second trunk CAN line 104, and further improving reliability of CAN communication.

In an exemplary embodiment, the display control device 201 is further included, and the display control device 201 is connected to the arbitration controller 106;

the arbitration controller 106 is further configured to generate status data of the first trunk CAN line 103 or the second trunk CAN line 104 based on the respiratory signal;

The arbitration controller 106 is further configured to send at least one of the status data, the alert signal, and the switch signal to the display control device 201.

In this embodiment, the display control device 201 may be a display controller of the vehicle itself. As shown in fig. 2, the arbitration controller 106 may be in signal connection with the display control device 201 through an arbitration CAN line 202, while the arbitration controller 106 may also be electrically connected with the display control device 201 through a second hard wire 203.

The arbitration controller 106 may generate status data of the first trunk CAN line 103 or the second trunk CAN line 104 based on the received respiration signals, e.g., the arbitration controller 106 may generate status data of the trunk CAN line of the first trunk CAN line 103 and the second trunk CAN line 104 that is in the access state at the current moment based on the received respiration signals.

The state data may be a fault state or a normal state, and the specific manner in which the arbitration controller 106 generates the state data based on the respiratory signal may be set according to actual requirements, for example, the arbitration controller 106 may determine whether the line switching condition is satisfied based on the respiratory signal, and generate the state data based on a determination result of whether the line switching condition is satisfied, when the line switching condition is satisfied, the state data of the trunk CAN line in the access state at the current moment is a fault state, and when the line switching condition is not satisfied, the state data of the trunk CAN line in the access state at the current moment is a normal state.

The arbitration controller 106 may also send at least one of status data, alarm signals, and switching signals to the display control device 201, so as to facilitate real-time monitoring and timely troubleshooting of the operating status of the vehicle CAN network by related personnel. It may be appreciated that the status data and the alarm signal may be transmitted to the display control device 201 through the arbitrated CAN line 202, and the switching signal may be transmitted to the display control device 201 through the second hard line 203, for example, when the arbitrated controller 106 determines that the line switching condition is met, the switching signal may be simultaneously sent to the first switching device 101, the second switching device 102 and the display control device 201 through the hard line, so that when the arbitrated CAN line 202 fails, the switching signal may also be sent to the display control device 201 through the hard line, so as to remind related personnel of timely troubleshooting, and by means of the redundant design of the arbitrated CAN line 202 and the hard line, the influence of the vehicle CAN network failure on the normal operation of the vehicle is further reduced.

In an exemplary embodiment, the tributary CAN lines 105 corresponding to the arbitration controller 106 include a first tributary CAN line and a second tributary CAN line;

the arbitration controller 106 is connected to the first trunk CAN line 103 via the first branch CAN line and to the second trunk CAN line 104 via the second branch CAN line.

In this embodiment, the arbitration controller 106 supports a dual-path CAN channel, and the branch CAN lines 105 corresponding to the arbitration controller 106 include a first branch CAN line and a second branch CAN line.

The arbitration controller 106 is in signal connection with the first trunk CAN line 103 through a first branch CAN line, that is, the positive CAN line of the first branch CAN line is in signal connection with the positive CAN line of the first trunk CAN line 103, and the negative CAN line of the first branch CAN line is in signal connection with the negative CAN line of the first trunk CAN line 103. Meanwhile, the arbitration controller 106 is further in signal connection with the second trunk CAN line 104 through a second branch CAN line, namely, the positive CAN line of the second branch CAN line is in signal connection with the positive CAN line of the second trunk CAN line 104, and the negative CAN line of the second branch CAN line is in signal connection with the negative CAN line of the second trunk CAN line 104, so that when the first trunk CAN line 103 is in an access state, the respiration signals sent by the node controllers 107 CAN be obtained through the first branch CAN line, and when the second trunk CAN line 104 is in an access state, the respiration signals sent by the node controllers 107 CAN be obtained through the second branch CAN line, the effectiveness of the obtained respiration signals is ensured, the accuracy of the trunk CAN line fault monitoring result is further improved, and the stability and reliability of the whole vehicle CAN network communication are further improved.

In an exemplary embodiment, as shown in fig. 3, the node controller 107 includes a first node controller 301 and a second node controller 302;

the first node controller 301 is connected to the first trunk CAN line 103 and the second trunk CAN line 104 through the corresponding branch CAN line 105 and the first switching device 101;

the second node controller 302 is connected to the first trunk CAN line 103 and the second trunk CAN line 104 via the respective branch CAN line 105 and the second switching device 102.

In this embodiment, the first node controller 301 and the second node controller 302 may be the node controllers 107 disposed at two farthest ends of the trunk CAN line, for example, the first node controller 301 may be an entire vehicle controller, and the second node controller 302 may be an engine controller.

The first node controller 301 may be connected to the first trunk CAN line 103 and the second trunk CAN line 104 through the respective branch CAN lines 105 and the first switching device 101, for example, the branch CAN line 105 corresponding to the first node controller 301 may include a first positive CAN line and a first negative CAN line, and the first positive CAN line may be respectively signal-connected to the positive CAN line of the first trunk CAN line 103 and the positive CAN line of the second trunk CAN line 104 through the first switching device 101 to control connection and disconnection of the first positive CAN line to the positive CAN line of the first trunk CAN line 103 and the positive CAN line of the second trunk CAN line 104 through the first switching device 101; the first negative CAN line CAN be respectively connected with the negative CAN line of the first trunk CAN line 103 and the negative CAN line of the second trunk CAN line 104 through the first switching device 101, so as to control connection and disconnection of the first negative CAN line with the negative CAN line of the first trunk CAN line 103 and the negative CAN line of the second trunk CAN line 104 through the first switching device 101.

The second node controller 302 may be connected to the first trunk CAN line 103 and the second trunk CAN line 104 through the corresponding branch CAN line 105 and the second switching device 102, for example, the branch CAN line 105 corresponding to the second node controller 302 may include a second positive CAN line and a second negative CAN line, and the second positive CAN line may be respectively connected to the positive CAN line of the first trunk CAN line 103 and the positive CAN line of the second trunk CAN line 104 through the second switching device 102, so as to control connection and disconnection of the second positive CAN line and the positive CAN line of the first trunk CAN line 103 and the positive CAN line of the second trunk CAN line 104 through the second switching device 102; the second negative CAN line CAN be respectively connected with the negative CAN line of the first trunk CAN line 103 and the negative CAN line of the second trunk CAN line 104 through the second switching device 102, so as to control connection and disconnection of the second negative CAN line with the negative CAN line of the first trunk CAN line 103 and the negative CAN line of the second trunk CAN line 104 through the second switching device 102.

When the first positive CAN line and the second positive CAN line are both connected with the positive CAN line of the first trunk CAN line 103 and the first negative CAN line and the second negative CAN line are both connected with the negative CAN line of the first trunk CAN line 103, the first trunk CAN line 103 is in an on state and the second trunk CAN line 104 is in an off state; when the first positive CAN line and the second positive CAN line are connected with the positive CAN line of the second trunk CAN line 104 and the first negative CAN line and the second negative CAN line are connected with the negative CAN line of the second trunk CAN line 104, the second trunk CAN line 104 is in an on state, and the first trunk CAN line 103 is in an off state, so that the switching of the first trunk CAN line 103 and the second trunk CAN line 104 is realized, the structure is simple, and the reliability of line switching is high.

In an exemplary embodiment, as shown in fig. 4, the first switching device 101 includes a first switch 401 and a second switch 402 that are disposed in an interlocking manner, and a third switch 403 and a fourth switch 404 that are disposed in an interlocking manner; the branch CAN line 105 corresponding to the first node controller 301 includes a first positive CAN line 405 and a first negative CAN line 406; the first positive CAN line 405 is connected to a positive CAN line CAN1+ of the first trunk CAN line 103 and a positive CAN line CAN2+ of the second trunk CAN line 104 through the first switch 401 and the second switch 402, respectively; the first negative CAN line 406 is connected with the negative CAN line CAN 1-of the first trunk CAN line 103 and the negative CAN line CAN 2-of the second trunk CAN line 104 through the third switch 403 and the fourth switch 404, respectively;

and/or the second switching device 102 includes a fifth switch and a sixth switch that are disposed in an interlocking manner, and a seventh switch and an eighth switch that are disposed in an interlocking manner; the branch CAN line 105 corresponding to the second node controller 302 includes a second positive CAN line and a second negative CAN line; the second positive electrode CAN line is connected with a positive electrode CAN line CAN1+ of the first trunk CAN line 103 and a positive electrode CAN2+ of the second trunk CAN line 104 through the fifth switch and the sixth switch respectively; the second negative CAN line is connected with the negative CAN line CAN 1-of the first trunk CAN line 103 and the negative CAN line CAN 2-of the second trunk CAN line 104 through the seventh switch and the eighth switch respectively.

In this embodiment, the branch CAN line 105 corresponding to the first node controller 301 includes a first positive CAN line 405 and a first negative CAN line 406, and the branch CAN line 105 corresponding to the second node controller 302 includes a second positive CAN line and a second negative CAN line.

The first switch 401 and the second switch 402 are interlocked, i.e. the second switch 402 is open when the first switch 401 is closed and the second switch 402 is closed when the first switch 401 is open. For example, the first switch 401 may be a normally closed relay, the second switch 402 may be a normally open relay, the first switch 401 and the second switch 402 share the first coil 407, when the first coil 407 is powered on, the first switch 401 is opened, the second switch 402 is closed, when the first coil 407 is powered off, the first switch 401 is closed, and the second switch 402 is opened, so as to realize an interlocking function.

The third switch 403 and the fourth switch 404 are interlocked, i.e. the fourth switch 404 is open when the third switch 403 is closed and the fourth switch 404 is closed when the third switch 403 is open. For example, the third switch 403 may be a normally closed relay, the fourth switch 404 may be a normally open relay, the third switch 403 and the fourth switch 404 share the second coil 408, when the second coil 408 is powered, the third switch 403 is opened, the fourth switch 404 is closed, when the second coil 408 is powered off, the third switch 403 is closed, and the fourth switch 404 is opened, so as to implement an interlocking function.

The specific structure of the second switching device 102 is the same as that of the first switching device 101. A fifth switch and a sixth switch Guan Husuo, i.e., the sixth switch is off when the fifth switch is closed and the sixth switch is on when the fifth switch is open. For example, the fifth switch may be a normally closed relay, the sixth switch may be a normally open relay, the fifth switch and the sixth switch Guan Gongyong are turned on when the third coil is powered, the sixth switch is turned off when the third coil is powered off, and the fifth switch is turned on when the third coil is powered off, and the sixth switch is turned off to realize the interlocking function.

The seventh switch and the eighth switch Guan Husuo are opened when the seventh switch is closed, and the eighth switch is closed when the seventh switch is opened. For example, the seventh switch may be a normally closed relay, the eighth switch may be a normally open relay, the seventh switch and the eighth switch Guan Gongyong are the fourth coil, the seventh switch is opened when the fourth coil is powered, the eighth switch is closed, the seventh switch is closed when the fourth coil is powered down, and the eighth switch is opened to achieve the interlock function.

The first positive CAN line 405 is connected with the positive CAN line CAN1+ signal of the first trunk CAN line 103 through a first switch 401, and the first positive CAN line 405 is also connected with the positive CAN line CAN2+ signal of the second trunk CAN line 104 through a second switch 402; the first negative CAN line 406 is connected with the negative CAN line CAN 1-signal of the first trunk CAN line 103 through the third switch 403, the first negative CAN line 406 is also connected with the negative CAN line CAN 2-signal of the second trunk CAN line 104 through the fourth switch 404, so that connection and disconnection of the branch CAN line 105 corresponding to the first node controller 301 and the first trunk CAN line 103 are controlled through the first switch 401 and the third switch 403, and connection and disconnection of the branch CAN line 105 corresponding to the first node controller 301 and the second trunk CAN line 104 are controlled through the second switch 402 and the fourth switch 404.

The second positive CAN line is connected with the positive CAN line CAN1+ signal of the first trunk CAN line 103 through a fifth switch, and the second positive CAN line is also connected with the positive CAN line CAN2+ signal of the second trunk CAN line 104 through a sixth switch; the second negative CAN line is connected with the negative CAN line CAN 1-signal of the first trunk CAN line 103 through a seventh switch, and is also connected with the negative CAN line CAN 2-signal of the second trunk CAN line 104 through an eighth switch, so that connection and disconnection of the branch CAN line 105 corresponding to the second node controller 302 and the first trunk CAN line 103 are controlled through the fifth switch and the seventh switch, and connection and disconnection of the branch CAN line 105 corresponding to the second node controller 302 and the second trunk CAN line 104 are controlled through the sixth switch and the eighth switch.

The switching signal may be a high level signal 1 and a low level signal 0 that are alternately set, that is, when the arbitration controller 106 determines that the line switching condition is satisfied, the output electrical signal is inverted in high-low level. The first coil 407, the second coil 408, the third coil and the fourth coil CAN be electrically connected with the arbitration controller 106 through the first hard wire 108, that is, the power supply and the power failure of the first coil 407, the second coil 408, the third coil and the fourth coil are synchronously controlled through switching signals, so that linkage control of the first switch 401, the second switch 402, the third switch 403, the fourth switch 404, the fifth switch, the sixth switch, the seventh switch and the eighth switch is realized, effective switching of the first trunk CAN line 103 and the second trunk CAN line 104 is realized, only one trunk CAN line 103 and the second trunk CAN line 104 at the same moment is ensured to be in an access state, the control is flexible and convenient, the reliability is high, the stability of CAN communication is further improved, and meanwhile, the first node controller 301 and the second node controller 302 do not need to support a two-way channel CAN.

In an exemplary embodiment, the node controllers 107 include at least one third node controller;

the branch CAN line 105 corresponding to the third node controller comprises a third positive CAN line and a third negative CAN line;

one end of the third positive CAN line is connected with the corresponding third node controller, the other end of the third positive CAN line is connected with a first branch and a second branch which are arranged in parallel, the other end of the first branch is connected with a positive CAN line CAN1+ of the first trunk CAN line 103, and the other end of the second branch is connected with a positive CAN line CAN2+ of the second trunk CAN line 104;

one end of the third negative CAN line is connected with the corresponding third node controller, the other end of the third negative CAN line is connected with a third branch and a fourth branch which are arranged in parallel, the other end of the third branch is connected with a negative CAN line CAN 1-of the first trunk CAN line 103, and the other end of the fourth branch is connected with a negative CAN line CAN 2-of the second trunk CAN line 104.

In the present embodiment, the third node controller is the node controller 107 that is not disposed at the two most distal ends of the trunk CAN line among the node controllers 107, that is, the third node controller is disposed between the first switching device 101 and the second switching device 102.

The branch CAN line 105 corresponding to the third node controller includes a third positive CAN line and a third negative CAN line. One end of the third positive CAN line is connected with a corresponding third node controller signal, the other end of the third positive CAN line is connected with a first branch and a second branch which are arranged in parallel, one end of the first branch, which is far away from the third positive CAN line, is connected with a positive CAN line CAN < 1+ > signal of the first trunk CAN line 103, and one end of the second branch, which is far away from the third positive CAN line, is connected with a positive CAN line CAN < 2+ > signal of the second trunk CAN line 104. One end of the third negative CAN line is connected with a corresponding third node controller signal, the other end of the third negative CAN line is connected with a third branch and a fourth branch which are arranged in parallel, one end of the third branch, which is far away from the third negative CAN line, is connected with a negative CAN line CAN 1-signal of the first trunk CAN line 103, and one end of the fourth branch, which is far away from the third negative CAN line, is connected with a negative CAN 2-signal of the second trunk CAN line 104, namely, communication signals output by the third node controller are simultaneously transmitted to the first trunk CAN line 103 and the second trunk CAN line 104, and the transmission of the signals is completed through the trunk CAN line in an access state in the first trunk CAN line 103 and the second trunk CAN line 104.

The CAN communication method provided by the invention is described below, and the CAN communication method described below is realized based on the CAN communication system described above, and the CAN communication method and the CAN communication system CAN be correspondingly referred to each other. As shown in fig. 5, the CAN communication method of the present invention at least includes the following steps:

s501, receiving respiratory signals sent by each node controller according to preset frequency through an arbitration controller; the arbitration controllers and the node controllers are connected with the first trunk CAN line and the second trunk CAN line through corresponding branch CAN lines;

s502, when the arbitration controller determines that the line switching condition is met based on the respiratory signal, the arbitration controller sends a switching signal to a first switching device and a second switching device; the first switching device and the second switching device control the first trunk CAN line or the second trunk CAN line to be switched into an access state based on the switching signal, and the first trunk CAN line and the second trunk CAN line are connected in parallel between the first switching device and the second switching device.

The invention also provides a working machine comprising the CAN communication system according to any of the embodiments, or the working machine uses the CAN communication method according to any of the embodiments.

In this embodiment, the work machine is a construction machine such as a crane, an excavator, or the like.

Fig. 6 illustrates a physical schematic diagram of an electronic device, as shown in fig. 6, which may include: processor 601, communication interface (Communications Interface) 602, memory 603 and communication bus 604, wherein processor 601, communication interface 602, memory 603 complete the communication between each other through communication bus 604. The processor 601 may invoke logic instructions in the memory 603 to perform a CAN communication method comprising: receiving respiratory signals sent by each node controller according to preset frequency through an arbitration controller; the arbitration controllers and the node controllers are connected with the first trunk CAN line and the second trunk CAN line through corresponding branch CAN lines;

the arbitration controller sends a switching signal to the first switching device and the second switching device when determining that the line switching condition is met based on the respiratory signal; the first switching device and the second switching device control the first trunk CAN line or the second trunk CAN line to be switched into an access state based on the switching signal, and the first trunk CAN line and the second trunk CAN line are connected in parallel between the first switching device and the second switching device.

Further, the logic instructions in the memory 603 described above may be implemented in the form of software functional units and may be stored in a computer readable storage medium when sold or used as a stand alone product. Based on this understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art or in a part of the technical solution, in the form of a software product stored in a storage medium, comprising several instructions for causing a computer device (which may be a personal computer, a server, a network device, etc.) to perform all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a random access Memory (RAM, random Access Memory), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

In another aspect, the present invention also provides a computer program product comprising a computer program stored on a non-transitory computer readable storage medium, the computer program comprising program instructions which, when executed by a computer, enable the computer to perform the CAN communication method provided by the above methods, the method comprising: receiving respiratory signals sent by each node controller according to preset frequency through an arbitration controller; the arbitration controllers and the node controllers are connected with the first trunk CAN line and the second trunk CAN line through corresponding branch CAN lines;

The arbitration controller sends a switching signal to the first switching device and the second switching device when determining that the line switching condition is met based on the respiratory signal; the first switching device and the second switching device control the first trunk CAN line or the second trunk CAN line to be switched into an access state based on the switching signal, and the first trunk CAN line and the second trunk CAN line are connected in parallel between the first switching device and the second switching device.

In yet another aspect, the present invention also provides a non-transitory computer readable storage medium having stored thereon a computer program which, when executed by a processor, is implemented to perform the above-provided CAN communication methods, the method comprising: receiving respiratory signals sent by each node controller according to preset frequency through an arbitration controller; the arbitration controllers and the node controllers are connected with the first trunk CAN line and the second trunk CAN line through corresponding branch CAN lines;

the arbitration controller sends a switching signal to the first switching device and the second switching device when determining that the line switching condition is met based on the respiratory signal; the first switching device and the second switching device control the first trunk CAN line or the second trunk CAN line to be switched into an access state based on the switching signal, and the first trunk CAN line and the second trunk CAN line are connected in parallel between the first switching device and the second switching device.

The apparatus embodiments described above are merely illustrative, wherein the elements illustrated as separate elements may or may not be physically separate, and the elements shown as elements may or may not be physical elements, may be located in one place, or may be distributed over a plurality of network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art will understand and implement the present invention without undue burden.

From the above description of the embodiments, it will be apparent to those skilled in the art that the embodiments may be implemented by means of software plus necessary general hardware platforms, or of course may be implemented by means of hardware. Based on this understanding, the foregoing technical solution may be embodied essentially or in a part contributing to the prior art in the form of a software product, which may be stored in a computer readable storage medium, such as ROM/RAM, a magnetic disk, an optical disk, etc., including several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the method described in the respective embodiments or some parts of the embodiments.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (10)

1. A CAN communication system, comprising: the controller comprises a plurality of controllers, a first switching device, a second switching device, a first trunk CAN line, a second trunk CAN line and branch CAN lines corresponding to the controllers; the first trunk CAN line and the second trunk CAN line are connected in parallel between the first switching device and the second switching device; the controllers are connected with the first trunk CAN line and the second trunk CAN line through the corresponding branch CAN lines; the plurality of controllers comprise an arbitration controller and a plurality of node controllers, and the arbitration controller is also connected with the first switching device and the second switching device;

The arbitration controller is used for receiving the breathing signals sent by each node controller according to the preset frequency, and sending switching signals to the first switching device and the second switching device when the breathing signals are determined to meet the line switching conditions;

the first switching device and the second switching device control the first trunk CAN line or the second trunk CAN line to be switched into an access state based on the switching signal.

2. The CAN communication system of claim 1, wherein the arbitration controller is configured to:

and if the respiratory signal sent by the target controller in each node controller is not received within the preset time, determining that the line switching condition is met, and if not, determining that the line switching condition is not met.

3. The CAN communication system of claim 2, wherein the arbitration controller is further configured to:

and generating an alarm signal when the respiration signal sent by the node controller outside the target controller is not received within a preset time period and the respiration signal sent by the target controller is received.

4. The CAN communication system of claim 3 further comprising a display control device, the display control device being coupled to the arbitration controller;

The arbitration controller is further configured to generate status data of the first trunk CAN line or the second trunk CAN line based on the respiratory signal;

the arbitration controller is further configured to send at least one of the status data, the alert signal, and the switch signal to the display control device.

5. The CAN communication system of any one of claims 1 through 4 wherein the tributary CAN lines to which the arbitration controller corresponds include a first tributary CAN line and a second tributary CAN line;

the arbitration controller is connected with the first trunk CAN line through the first branch CAN line and connected with the second trunk CAN line through the second branch CAN line.

6. The CAN communication system of any one of claims 1 through 4 wherein the node controllers include a first node controller and a second node controller;

the first node controller is connected with the first trunk CAN line and the second trunk CAN line through the corresponding branch CAN lines and the first switching device;

the second node controller is connected with the first trunk CAN line and the second trunk CAN line through the corresponding branch CAN line and the second switching device.

7. The CAN communication system of claim 6, wherein the first switching device includes first and second switches in an interlocked arrangement, and third and fourth switches in an interlocked arrangement; the branch CAN line corresponding to the first node controller comprises a first positive CAN line and a first negative CAN line; the first positive CAN line is connected with the positive CAN line of the first trunk CAN line and the positive CAN line of the second trunk CAN line through the first switch and the second switch respectively; the first negative CAN line is connected with the negative CAN line of the first trunk CAN line and the negative CAN line of the second trunk CAN line through the third switch and the fourth switch respectively;

and/or the second switching device comprises a fifth switch and a sixth switch which are arranged in an interlocking way, and a seventh switch and an eighth switch which are arranged in an interlocking way; the branch CAN line corresponding to the second node controller comprises a second positive CAN line and a second negative CAN line; the second positive CAN line is connected with the positive CAN line of the first trunk CAN line and the positive CAN line of the second trunk CAN line through the fifth switch and the sixth switch respectively; the second negative CAN line is connected with the negative CAN line of the first trunk CAN line and the negative CAN line of the second trunk CAN line through the seventh switch and the eighth switch respectively.

8. The CAN communication system of any one of claims 1 through 4 wherein the node controllers include at least one third node controller;

the branch CAN line corresponding to the third node controller comprises a third positive CAN line and a third negative CAN line;

one end of the third positive CAN line is connected with the corresponding third node controller, the other end of the third positive CAN line is connected with a first branch and a second branch which are arranged in parallel, the other end of the first branch is connected with the positive CAN line of the first trunk CAN line, and the other end of the second branch is connected with the positive CAN line of the second trunk CAN line;

one end of the third negative CAN line is connected with the corresponding third node controller, the other end of the third negative CAN line is connected with a third branch and a fourth branch which are arranged in parallel, the other end of the third branch is connected with the negative CAN line of the first trunk CAN line, and the other end of the fourth branch is connected with the negative CAN line of the second trunk CAN line.

9. A CAN communication method, comprising:

receiving respiratory signals sent by each node controller according to preset frequency through an arbitration controller; the arbitration controllers and the node controllers are connected with the first trunk CAN line and the second trunk CAN line through corresponding branch CAN lines;

The arbitration controller sends a switching signal to the first switching device and the second switching device when determining that the line switching condition is met based on the respiratory signal; the first switching device and the second switching device control the first trunk CAN line or the second trunk CAN line to be switched into an access state based on the switching signal, and the first trunk CAN line and the second trunk CAN line are connected in parallel between the first switching device and the second switching device.

10. A work machine, characterized in that it comprises a CAN communication system according to any one of claims 1 to 8 or that it uses a CAN communication method according to claim 9.

Images