JP7522301B2 - Vehicle control device - Google Patents

Description

The present invention relates to an on-board control device mounted in a vehicle.

It is known that the increase in the number of on-board control devices installed in vehicles is partially preventing fuel economy improvement due to the increase in weight of the on-board control device itself and the vehicle harness that connects the on-board control devices.

In order to reduce the weight of the vehicle harness between the on-board control device and the on-board electrical load, an actuator control device is known in which the on-board control device is placed near the on-board electrical load or is integrated with the on-board electrical load.

Also known is an on-vehicle control device that integrates a plurality of on-vehicle control devices mounted on a vehicle, and further integrates some of the functions of an actuator control device.

The integrated on-board control device calculates the operation amount of the vehicle electrical load based on external input information, and instructs the actuator control device on the operation amount via a communication line, or receives information from the actuator control device. This allows the vehicle harness connecting the integrated on-board control device and the actuator control device to be limited to power lines and communication lines, reducing the amount of vehicle harness.

If the amount of communication between the integrated vehicle control device and the actuator control device increases, the increase in the weight of the vehicle harness can be kept to a minimum by simply adding more communication lines.

On the other hand, since the integrated on-board control device and the actuator control device are connected only by a communication line, technology is needed to ensure reliability in order to keep the vehicle system in a safe state even if a failure occurs in the communication line. One such technology is described in Patent Document 1.

Patent Document 1 describes a technique aimed at providing an in-vehicle communication system that can improve the reliability of the system when a communication failure occurs in a part of the in-vehicle system.

JP 2009-029237 A

However, in the technology described in the above Patent Document 1, when a communication failure occurs in one communication bus of the vehicle system, communication is limited to switching to another communication bus where no communication failure occurs, and there is no sufficient consideration given to ensuring high reliability even when a communication failure occurs. In other words, the technology described in Patent Document 1 has a problem in that there is no consideration given to ensuring high reliability of communication data when a communication failure occurs while suppressing the vehicle harness weight due to the addition of communication lines between the on-board control devices.
The object of the present invention is to solve such technical problems and to provide an on-board control device that can suppress an increase in the weight of the vehicle harness and improve the reliability of the on-board communication system even if a communication failure occurs in part of the on-board communication system.

In order to achieve the above object, the present invention is configured as follows.

A vehicle control device includes a plurality of communication modules each having a non-arbitration communication unit that performs communication in a non-arbitration communication method and an arbitration communication unit that performs communication in an arbitration communication method, each of which is connected to a plurality of communication buses that are connected to other control devices, and a communication control unit that is capable of switching whether each of the plurality of communication circuits communicates via the non-arbitration communication unit or the arbitration communication unit, and the communication control unit is configured to switch the communication between the non-arbitration communication unit and the arbitration communication unit when no failure occurs in the plurality of communication buses. The communication control unit switches to communication via a communication unit, and before starting communication via the non-arbitration communication unit and the arbitration communication unit of each of the multiple communication modules, the non-arbitration communication function of the non-arbitration communication unit and the arbitration communication function of the arbitration communication unit are set in advance, and a diagnostic data transmission period is set in a transmission blank period for communication via the non-arbitration communication unit, and the communication control unit diagnoses whether a failure has occurred that prevents data from being sent or received during the diagnostic data transmission period, and switches from communication via the non-arbitration communication unit to communication via the arbitration communication unit based on the diagnosis result .

According to the present invention, it is possible to provide an in-vehicle control device that can suppress an increase in the weight of a vehicle harness and can improve the reliability of an in-vehicle communication system even if a communication failure occurs in part of the in-vehicle communication system.

1 is a schematic configuration diagram of a system including an on-vehicle control device to which the present invention is applied; FIG. 2 is an internal configuration diagram of the on-board control device according to the first embodiment. FIG. 2 is an internal configuration diagram of the on-board control device according to the first embodiment. FIG. 2 is an internal configuration diagram of the on-board control device according to the first embodiment. FIG. 2 is an internal configuration diagram of the on-board control device according to the first embodiment. FIG. 2 is an internal configuration diagram of the on-board control device according to the first embodiment. FIG. 11 is an internal configuration diagram of an on-board control device according to a second embodiment. FIG. 13 is an explanatory diagram of a database according to the third embodiment. FIG. 13 is an explanatory diagram of a database according to the third embodiment. FIG. 13 is a diagram of a comparative example for explaining Example 4. FIG. 13 is an explanatory diagram of a fourth embodiment. FIG. 13 is an explanatory diagram of a fourth embodiment. 13 is an operation time chart in the fifth embodiment. 23 is an operation flowchart according to the sixth embodiment. FIG. 13 is a block diagram according to a sixth embodiment. 23 is an operation flowchart according to the seventh embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of an on-board control device according to the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are given the same reference numerals, and duplicated description will be omitted.

As an example, an on-board control device according to the present invention is applied to a vehicle control system including an on-board control device 10 and an actuator control device 20 shown in Fig. 1. In the vehicle control system shown in Fig. 1, a microcomputer 30 of the on-board control device 10 calculates a control amount of a vehicle electric load (not shown) based on various information, and transmits a command to the actuator control device 20 having the microcomputer 30 via a communication circuit 40 and a communication bus 50.

That is, the multiple communication circuits 40 are connected to the communication bus 50 and transmit and receive control signals. The actuator control device 20 controls the above-mentioned vehicle electrical loads and transmits control information to the vehicle control device 10 via the communication bus 50.

Example 1
FIG. 2 is a diagram showing an internal configuration of the on-board control device 10 according to the first embodiment of the present invention.

In FIG. 2 , the on-vehicle control device 10 is a so-called ECU (Electronic Control Unit), and includes a microcomputer (abbreviation of “microcontroller”) 30 and a communication circuit 40 .

The communication circuit 40 is a communication circuit capable of performing, for example, CAN communication, which is commonly used in the on-board control device 10 .

In order to communicate with other control devices via the communication circuit 40 , the microcomputer 30 includes a calculation unit 100 , a communication method switching unit 110 , a communication module 120 , and a fault diagnosis result unit 150 .

The communication method switching unit 110 switches between two communication methods built into a communication module (described later) by operating a changeover switch 110a and a changeover switch 110b based on the fault state of the communication bus 50 stored in the fault diagnosis result unit 150.

The communication module 120 includes a non-arbitration communication unit 130 and an arbitration communication unit 140. The non-arbitration communication unit 130 is a communication unit that performs, for example, one-to-one transmission-only communication or reception-only communication, and transmits and receives only transmission and reception data to and from the communication bus 50 (shown in FIG. 1). In the non-arbitration communication unit 130, the communication baud rate can be set arbitrarily.

That is, for example, it is possible to set a communication baud rate that is two or three times as fast as the communication baud rate defined in the CAN communication standard.

The arbitration communication unit 140 is a communication unit that performs, for example, one-to-many, many-to-one, and many-to-many transmission and reception communication, and transmits and receives arbitration data that determines synchronization and priority of communication timing in addition to transmission and reception data, to the communication bus 50. In addition, in the arbitration communication unit 140, the communication baud rate is set to a communication baud rate specified in a conventional communication standard, for example, the CAN communication standard, in order to perform arbitration processing.

There are at least two communication modules 40, each connected to one of the multiple communication circuits 40, and each of the multiple communication modules 40 performs send-only communication using a non-arbitration communication method or receive-only communication using a non-arbitration communication method, and has a non-arbitration communication unit 130 that communicates control signals, and an arbitration communication unit 140 that communicates control signals using the arbitration communication method.

The calculation unit 100, the communication method switching unit 110, and the old book diagnosis result unit 150 constitute a communication control unit, and the communication control units 100, 110, and 150 diagnose whether a failure has occurred that prevents the transmission and reception of control signals by the multiple communication circuits 40, and based on the diagnosis results, select either communication of control signals by the non-arbitration communication unit 130 or communication of control signals by the arbitration communication unit 140.

Next, a communication control process of the non-arbitration communication method by the on-board control device 10 of the first embodiment will be described with reference to FIG.

When the communication bus 50 is normal and has no fault such as a broken wire, information that the communication bus is normal is stored in the fault diagnosis result 150. Based on the information in the new fault diagnosis result 150, the communication method switching unit 110 selects the non-arbitration communication unit 130 for the two communication modules 120. In other words, both the changeover switch 110a and the changeover switch 110b are set to the non-arbitration communication unit 130 side.

The calculation section 100 of the microcomputer 30 performs communication by setting one of the two communication modules 120 for transmission-only communication and the other for reception-only communication, based on the state of the communication method switching section 110.

In other words, when the communication control units 100, 110, and 150 select communication of control signals by the non-arbitration communication unit 130, the two communication modules 120 operate exclusively for transmission processing and reception processing, respectively.

Compared to communication via the arbitration communication unit 140, communication via the non-arbitration communication unit 130 transmits and receives only transmit and receive data that does not contain arbitration data to the communication bus 50, so that more transmit data or receive data can be transmitted and received on the communication bus 50. In other words, the transmit-only processing of non-arbitration communication can be performed under a high communication bus load state, allowing for faster communication.

Next, the communication control process of the arbitration communication method by the on-board control device 10 of the first embodiment will be described in detail with reference to FIG. 3 and FIG.

When one of the two communication buses 50 connected to each of the two communication circuits 40 is in a fault state, for example, a fault such as a broken wire, the calculation unit 100 diagnoses whether or not a fault has occurred that prevents the communication circuit 40 from sending or receiving a control signal, detects the fault state, and stores information that the communication bus has failed in the fault diagnosis result unit 150. Based on the information from the fault diagnosis result unit 150, the communication method switching unit 110 selects the arbitration communication unit 140 for the two communication modules 120.

The calculation unit 100 of the microcomputer 30 performs transmission and reception processing using only the communication module connected to the non-faulty communication bus 50 of the two communication modules 120, based on the state of the communication method switching unit 110. That is, in the case of the state shown in Fig. 3, the changeover switch 110a on the communication module 40 side connected to the non-faulty communication bus 50 is switched from the state shown in Fig. 3 to the arbitration communication unit 140 side. In the case of the state shown in Fig. 4, the changeover switch 110b on the communication module 40 side connected to the non-faulty communication bus 50 is switched from the state shown in Fig. 4 to the arbitration communication unit 140 side.

Compared to communication via the non-arbitration communication unit 130, communication via the arbitration communication unit 140 does not allow high-speed communication because it includes arbitration data other than the transmitted and received data. However, on the other hand, it is possible to perform and continue transmitting and receiving processing operations for control signals on a single communication bus 50, that is, between the vehicle control unit 10 and the actuator control unit 20, while ensuring high reliability.

The on-vehicle control device 10 and other control devices whose operations are controlled by the on-vehicle control device 10 are connected via a communication bus 50, and the vehicle harness can be limited to the communication bus 50, thereby suppressing an increase in the weight of the vehicle harness. Furthermore, if a failure occurs in the communication bus 50, a non-failed communication bus is used for arbitration communication, so that reliability that keeps the vehicle system in a safe state can be ensured even if a fault occurs in the communication bus 50.

Next, a system in which a plurality of on-vehicle control devices and an actuator control device are connected will be described with reference to FIGS.

5 is a diagram for explaining a system in which two on-board control devices are connected in the embodiment 1. The operation when a failure occurs in the communication bus 50 is similar to the examples shown in FIGS.

In FIG. 5, the on-vehicle control device 10 is connected, via a communication circuit 40 of the on-vehicle control device 10, to a communication circuit 40 of an actuator control device 20 which also serves as an on-vehicle control device.

The non-arbitration type transmission data transmitted from the on-board controller 10 to the actuator controller 20 is received via the non-arbitration communication unit 130 of the actuator controller 20, and the arbitration type transmission data is received via the arbitration communication unit 140 of the actuator controller 20. The transmission data transmitted from the actuator controller 20 to the on-board controller 10 is also received via the non-arbitration communication unit 130 or the arbitration communication unit 140 of the on-board controller 10 in the same manner as described above.

Fig. 6 is a diagram illustrating a system in which two actuator control devices 20A and 20B are connected as an on-vehicle control device, in comparison with Fig. 5. The on-vehicle control device 10 is provided with two communication modules 120, and data is transmitted and received between the actuator control devices 20A and 20B. Transmission and reception of transmission data and reception data is performed via the non-arbitration communication unit 130 or arbitration communication unit 140 of each control device, as described above.

In the systems shown in Figures 5 and 6, as in the examples described in Figures 2 to 4, it is possible to suppress an increase in the weight of the vehicle harness, and to ensure reliability in which the vehicle system is kept safe even if a failure occurs in the communication bus 50.

From the above, when the communication bus 50 is in a normal state, it is possible to send and receive more data than with conventional CAN communication by using the non-arbitration communication method of the communication module 120 using the CAN communication circuit.

In addition, if the communication bus 50 is in a faulty state, the other non-faulty communication bus 50 can be used to continue transmission and reception between the vehicle control device and the actuator control device by using the arbitration communication method of the communication module 120.

As a result, it is possible to suppress an increase in the weight of the vehicle harness without adding a communication bus to send and receive communication data volumes greater than those of the conventional CAN communication standard, and it is possible to ensure the reliability of the in-vehicle communication system even if a communication failure occurs in part of the in-vehicle communication system.

Example 2
Next, a second embodiment of the on-vehicle control device according to the present invention will be described.

The on-board control device 10 according to the second embodiment is different from the first embodiment in that it takes into consideration the influence of a delay in switching from the non-arbitrated communication method in normal operation to the arbitrated communication method in the event of a failure. In other respects, the first embodiment and the second embodiment have the same configuration.

Specifically, the second embodiment is an example in which the communication method can be switched in a timely manner when a failure occurs by performing initial settings of each communication module setting unit (described later) before starting communication.

In other words, before the calculation unit 100 included in the communication control unit starts communication of control signals by the non-arbitration communication unit 130 and the arbitration communication unit 140 of the communication module 120, the calculation unit 100 sets the non-arbitration communication function of the non-arbitration communication unit 130 of the communication module 120 and the arbitration communication function of the arbitration communication unit 140 in advance.

FIG. 7 is a diagram showing an internal configuration of an on-board control device 10 according to a second embodiment of the present invention.

As shown in FIG. 7 , the on-board control device 10 of the second embodiment further includes a power switch monitor unit 250 that monitors the start-up signal of the on-board control device 10 .

The vehicle battery 200 is connected to the on-board control device 10 via a power switch 210, and power from the vehicle battery 200 is input to a power supply circuit 220 and a power switch monitor unit 250. The power switch monitor unit 250 outputs the result of monitoring the power switch 210 that it detects to the microcomputer 30. The microcomputer 30 checks the value output from the power switch monitor unit 250 and determines the state of the power switch 210.

For example, if the output value of the power switch monitor unit 250 is High, it is determined that the power switch 210 is in an energized state, and if the output value of the power switch monitor unit 250 is Low, it is determined that the power switch 210 is in an OFF state. The power supply circuit 220 also generates a power supply voltage used inside the in-vehicle control device 10, and supplies the power supply voltage to the microcomputer 30, for example.

Generally, various functional modules are built into the microcomputer 30, and before each functional module is operated, information for operating the functional module must be set in advance. In the communication module 120 included in the second embodiment, for example, communication baud rate, transmission only, reception only, etc. must be set before starting communication.

After the power switch 210 is energized, a power supply voltage is supplied from the power supply circuit 220 to the microcomputer 30, and the microcomputer 30 is started, the calculation unit 100 of the microcomputer 30 checks the output value of the power switch monitor unit 250 and determines that the control device 10 has been started. After that, before starting communication, the calculation unit 100 sets information required for the operation of the communication module 120 in the communication module setting unit A230 and the communication module setting unit B240 provided in each of the two communication modules 120. In other words, immediately after the on-board control device 10 is started, the calculation unit 100 sets information (functions) required for the operation of the communication module 120 in the communication module setting unit A230 and the communication module setting unit B240.

In contrast, if the communication module setting unit A230 and the communication module setting unit B240 are set immediately before use is started after communication has started, then if a failure occurs in the communication bus 50 after communication has started and before the start of the setting or if a failure occurs in the communication bus 50 during the setting period, the communication method will be switched to the arbitration communication method in which the arbitration communication unit 140 operates. In this case, a problem occurs in that communication processing cannot be performed during the period in which the communication module setting unit B240 is being set.

To address the above problem, as described above, the information required for the operation of the communication module 120 is set in the communication module setting unit A230 and the communication module setting unit B240 immediately after the vehicle control device 10 is started up. In the event of a failure in the communication bus 50, the communication baud rate, etc. have already been set in the communication module setting unit B240, so that the communication method can be switched from the non-arbitrated communication method to the arbitrated communication method in a timely manner.

According to the on-board control device 10 of the second embodiment, in addition to obtaining the same operational effects as those of the first embodiment, in addition to performing initial settings in the communication module setting units A230 and B240 before starting communication, when a failure occurs in the communication bus 50, it is not necessary to set the communication module setting unit B240 of the arbitration communication unit 140 of the communication module 120, and the time during which communication processing cannot be performed can be shortened. As a result, it becomes possible to switch the communication method in a timely manner.

Example 3
Next, a third embodiment of the on-vehicle control device will be described with reference to FIGS. 8A and 8B. FIG.

The on-board control device 10 of the third embodiment is different from the first embodiment in that it takes into consideration the influence of a delay in switching from the non-arbitrated communication method in normal operation to the arbitrated communication method in the event of a failure. The other points and configuration are the same as those of the first embodiment.

Specifically, in the third embodiment, the priority of transmission and reception processing in each communication method is determined in advance before starting communication, so that the communication method can be switched in a timely manner when a failure occurs. The effects of the third embodiment are similar to those of the second embodiment.

8A and 8B show a database for determining the priority of the transmission/reception process of the microcomputer 30 in the third embodiment. The calculation unit 100 included in the communication control unit has a database in which the priority of the transmission/reception process of the data transmitted/received by the arbitration communication unit 140 is set. The arbitration communication unit 140 performs the transmission/reception process of the control signal, which is data, according to the priority set in the database.

FIG. 8A shows the non-arbitration communication method and the arbitration communication method of the transmission processing database, and FIG. 8B shows the non-arbitration communication method and the arbitration communication method of the reception processing database.

8A shows the priority of transmission data in the arbitration communication system. The priority is determined in the order of data a, data b, and data c, and the transmission cycle is 5 ms for data a, 10 ms for data b, and 20 ms for data c.

8B, the priority of received data in the arbitration communication system is set. The priority is determined in the order of data 1, data 2, and data 3, and the reception cycle is 10 ms for data 1, 20 ms for data 2, and 20 ms for data 3.

Compared with the non-arbitration communication method, the arbitration communication method requires the priority of transmitted and received data to be determined in advance, and the priority of transmitted and received data in the arbitration communication method is stored, for example, in the microcomputer 30. When a failure occurs in the communication bus 50, the arbitration communication unit 140 can process data according to the predetermined priority without the need to calculate the priority each time a failure occurs.

According to the on-board control device 10 of the third embodiment, in addition to obtaining the same operational effects as those of the first and second embodiments described above, by determining the priority of data transmitted and received by the arbitration communication method before starting communication, when a failure occurs in the communication bus 50, it is not necessary to set the priority in the communication processing via the arbitration communication unit 240 of the communication module 120, and the time during which communication processing cannot be performed can be shortened. As a result, it becomes possible to switch the communication method in a timely manner.

Example 4
Fourth Embodiment Next, an on-vehicle control device according to a fourth embodiment will be described with reference to FIGS.

The on-board control device according to the fourth embodiment differs from the above-described first embodiment in that it further considers shortening the time required to detect a fault state of the communication bus 50. Other configurations of the fourth embodiment are similar to those of the first embodiment.

FIG. 9 is a diagram of a comparative example for explaining the fourth embodiment, and is a time chart for explaining the operation of the on-board control device 10 according to the first embodiment described above.

Figure 9 shows a time chart (Figure 9(A)) of data transmitted from the vehicle control device 10 to the actuator control device 20 by the non-arbitration communication unit 130, and a time chart (Figure 9(B)) of data received from the actuator control device 20 to the vehicle control device 10, with time T100 to time T220 indicating the period of each transmitted and received data.

9A, in the transmission process from the on-board brake device 10 to the actuator control device 20, transmission data A, B, and C required for the actuator control device 20 are transmitted in the period from time T100 to time T110. The period from time T110 to time T120 is a transmission blank period in which no transmission process is performed.

For example, even if a communication bus failure occurs at time T400 between time T110 and time T120, that is, a state occurs in which transmission processing from the vehicle control device 10 to the actuator control device 20 cannot be performed correctly, using a general communication bus failure detection method described later in FIG. 11, the vehicle control device 10 is not performing transmission processing during this period, and a communication bus failure that occurs between time T110 and time T120 can only be detected after time T120, and the failure cannot be detected in a timely manner.

Fig. 10 is a time chart for explaining the operation of the on-board control device 10 according to the fourth embodiment. The data transmission process of the on-board control device 10 and the actuator control device 20 between time T100 and time T110 shown in Fig. 10(A) and between time T200 and time T210 shown in Fig. 10(B) is the same as that explained in Fig. 9. The fourth embodiment differs from the first embodiment in that a diagnostic data transmission period for the purpose of early detection of a communication bus failure is provided between time T110 and time T120.

10, when a communication bus failure occurs at time T400, the diagnostic data transmission period is from time T110 to time T120, and the on-board controller 10 detects that normal transmission is not possible and recognizes that the communication bus 50 is in a fault state. Also, the actuator controller 20 detects that diagnostic data that should be received between time T110 and time T120 is not normally received and recognizes that the communication bus 50 is in a fault state.

In other words, the vehicle control device 10 and the actuator control device 20 can detect a failure in the communication bus 50 at timing T400, which is earlier than the end time T120 of the diagnostic data transmission period, and can switch the non-arbitrated transmission-only communication from the actuator control device 20 to the vehicle control device 10 to the arbitrated communication method of transmission and reception communication.

Fig. 11 is an internal block diagram of the communication circuit 40 of the on-board control device 10. In Fig. 11, when the communication bus 50 is in a normal state, when the microcomputer 30 transmits data from the TX circuit 41 of the communication circuit 40, the transmission data is input to the microcomputer 30 via the RX circuit 42 of the communication circuit 40.

On the other hand, when a failure occurs on the communication bus 50, even if data is transmitted from the TX circuit 41 of the communication circuit 40 via the communication bus 50, the transmission data input from the RX circuit 42 of the communication circuit 40 to the microcomputer 30 is a fixed value that depends on the failure of the communication bus 50. In other words, the microcomputer 30 can check the state of the communication bus 50 by checking the data transmitted from the TX circuit 41 of the communication circuit 40 and the transmission data received by the RX circuit 42 of the communication circuit 40.

The operation of the communication circuit 40 of the on-vehicle control device 10 is the same as the operation of the communication circuit 40 of the actuator control device 20, and the actuator control device 20 can perform the same fault diagnosis.

In other words, a diagnostic data transmission period is set for the communication of control signals by the non-arbitration communication unit 130, and the communication control unit diagnoses whether a failure has occurred that prevents control signals from being sent or received during the diagnostic data transmission period, and based on the diagnosis results, switches from communication of control signals by the non-arbitration communication unit 130 to communication of control signals by the arbitration communication unit 140.

According to the fourth embodiment, in addition to being able to obtain the same effect as the first embodiment, by performing communication for diagnosing the transmission and reception data during the transmission blank period, it is possible to reduce the time required to detect a fault condition in the communication bus 50.

The fourth embodiment is also applicable to the first to third embodiments.

Example 5
Next, a fifth embodiment of the present invention will be described with reference to FIG.

The in-vehicle control device 10 of the present embodiment 5 is different from the above-described embodiment 4 in that it detects a failure on the communication bus 50 during transmission of communication data and considers switching the communication method between a plurality of control devices. Other configurations of the embodiment 5 are similar to those of the embodiment 4.

In Example 5, the calculation unit 100 included in the communication control unit has a fault detection function that detects a fault in the control signal received by the non-arbitration communication unit 130, and when the calculation unit 100 included in the communication control unit detects a fault in the control signal received by the non-arbitration communication unit 130, it switches from communication of the control signal by the non-arbitration communication unit 130 to communication of the control signal by the arbitration communication unit 140.
FIG. 12 is a time chart illustrating the operation of the on-board control device 10 according to the fifth embodiment.

Figure 12 shows a time chart (Figure 12 (A)) of data transmitted from the vehicle control device 10 to the actuator control device 20, and a time chart (Figure 12 (B)) of data received from the actuator control device 20 to the vehicle control device 10, with times T100 to T220 indicating the periods of each transmitted and received data.

In the transmission process from the in-vehicle control device 10 to the actuator control device 20, necessary transmission data is transmitted to the actuator control device 20 during the period from time T100 to time T110. If a failure occurs on the communication bus 50 at the timing of time T400 during this period, communication will be interrupted during the transmission of communication data from the in-vehicle control device 10. If communication is interrupted during the transmission of communication data, the actuator control device 20 detects a failure on the communication bus 50 by, for example, failure detection using a CRC of the communication data or failure detection using an inability to receive communication data within a certain period of time, and receives a failure communication in the received data after time T400. After that, an initialization process is performed at time T210 to switch the communication method from the non-arbitration method to the arbitration method, and communication between the actuator control device 20 and the in-vehicle control device 10 using the arbitration communication method is resumed.

FIG. 12 shows an example of an occurrence in which reception of received data is not possible due to a failure of the communication bus 50. However, even in the event of a failure of something other than the communication bus 50, for example, the communication IC of the non-arbitration communication unit 130, it is possible to perform an initialization process to switch the communication method from the non-arbitration method to the arbitration method, and to resume communication using the arbitration communication method.

According to the present embodiment 5, it is possible to obtain the same effect as in the embodiment 1, and in addition, it is also possible to detect failures in the communication IC other than failures on the communication bus 50 during the transmission of communication data, and to switch the communication method between multiple control devices.

Example 6
Sixth embodiment Next, an on-board control device 10 according to a sixth embodiment will be described with reference to FIG.

If communication using the non-arbitration communication method is not possible, communication is performed by switching to the arbitration communication method using a separate communication circuit. However, if the arbitration communication method unit 140 is malfunctioning and the non-arbitration communication unit 130 also malfunctions, there is a problem that it will become impossible to communicate with other control devices.

Therefore, the sixth embodiment is characterized in that it is confirmed that arbitration communication can be performed immediately after power-on of the in-vehicle control device 10. Note that other configurations of the sixth embodiment are the same as those of the first embodiment, and therefore are not illustrated.

13 is executed immediately after the power supply of the in-vehicle control device 10 is turned on. First, in step S100, the calculation unit 100 of the microcomputer 30 executes various initialization processes. In step S110, the communication method switching unit 110 is set to the arbitration communication method executed by the arbitration communication unit 140, and transmission and reception processes are performed to execute an initial communication diagnosis process.

Specifically, transmission data in the arbitration communication method is transmitted from the on-board controller 10 to the actuator controller 20. In addition, transmission data in the arbitration method is transmitted from the actuator controller 20 to the on-board controller 10.

In step S120, it is determined whether the above-mentioned arbitration communication has been performed correctly between the two control devices 10 and 20, that is, whether the transmission and reception process of the control signal by the arbitration communication unit 140 is normal. If it is determined that the arbitration communication unit 140 is normal and the arbitration communication has been performed correctly, the process proceeds to step S130, the communication method of the in-vehicle control device 10 is changed from the arbitration method to the non-arbitration method, the process immediately after power-on is completed, and communication of the control signal by the non-arbitration communication unit 130 is started.

In step S120, if it is determined that the arbitration communication unit 140 is not normal and the arbitration communication is not being performed correctly, the process proceeds to step S140.

In step S140, a failure flag is set to indicate that the arbitration communication process has not been performed correctly. When the failure flag is set, the microcomputer 30 of the in-vehicle control device 10 causes the display device (display unit) 70 to display that the arbitration communication process has not been performed correctly, as shown in FIG. 14. This allows the user to recognize that the arbitration communication process has not been performed correctly, and when communication using the non-arbitration communication method has failed, the user can recognize in advance that communication using the arbitration communication method cannot be performed either. When the process of step S140 is completed, the process proceeds to step S130.

According to this embodiment 6, in addition to being able to obtain the same effect as in embodiment 1, by checking in advance whether communication is possible using the arbitration communication method immediately after power-on of the vehicle control device 10, it is possible to avoid a situation in which communication is unexpectedly impossible using the non-arbitration communication method and the arbitration communication method.

(Example 7)
Seventh embodiment Next, an on-board control device 10 according to a seventh embodiment will be described with reference to Fig. 15. The circuit configuration of the on-board control device 10 is similar to that of the first embodiment, and therefore is not shown in the drawings.

When communication using the non-arbitration communication method is not possible, the method is switched to the arbitration communication method in another communication circuit, and communication is performed, and transmission and reception processing between the control devices is stopped in the communication circuit incapable of performing non-arbitration communication.

Furthermore, if a failure occurs in a communication circuit network that uses the arbitrated communication method, there is a problem that it becomes impossible to communicate with other control devices because the sending and receiving processes between control devices are stopped in communication circuits that cannot perform non-arbitrated communication.

Therefore, in the seventh embodiment, in a communication circuit in which non-arbitration communication was not possible, a check is periodically made to see whether transmission and reception processing can be resumed, and if it is possible to resume, non-arbitration communication is resumed.

In other words, the communication control unit including the calculation unit 100 diagnoses whether a failure has occurred that prevents the transmission and reception of control signals, and if a failure has occurred, switches from communication via the non-arbitration communication unit 130 to communication via the arbitration communication unit 140, and after a certain period of time has elapsed, determines whether communication via the non-arbitration communication unit 130 is possible, and if it determines that communication via the non-arbitration communication unit 130 is possible, resumes communication via the non-arbitration communication unit 130.

The flowchart shown in Figure 15 shows a scheduled task processing that is executed at regular intervals in the calculation unit 100 included in the communication control unit after the initialization processing following power-on of the vehicle control device 10 in Example 7 is completed.

First, in step S200, regular control processing is performed for various controls such as setting a failure flag for the communication bus 50 that is faulty, and the process proceeds to step S210. In step S210, it is confirmed whether a communication bus failure flag that disables communication by the non-arbitration communication method has been set. If the communication bus failure flag has not been set, the process proceeds to step S220, where a communication bus failure diagnosis is performed.

In step S220, for example, it is diagnosed that communication data cannot be transmitted or received, and the process proceeds to step S230.

In step S230, it is determined (diagnosed) whether or not a communication bus failure has occurred. If a communication bus failure has not occurred, the scheduled task processing is completed.
If a communication bus failure has occurred, the process proceeds to step S240.

In step S240, transmission and reception processing of the communication circuit network connected to the communication network in which the communication bus failure has occurred is stopped, and the process proceeds to step S250.

In step S250, the communication mode of the communication circuit network in which no communication bus failure has occurred is switched from non-arbitration communication to arbitration communication, and the process proceeds to step S260.

In step S260, a communication mode switching status record indicating that the communication mode of the communication circuit network in which no communication bus failure has occurred has been switched (a communication bus failure flag is set), and the process proceeds to step S270.

In step S270, communication is resumed on the communication circuit network where no communication bus failure has occurred. Thereafter, the scheduled control process is performed at regular intervals.

After the lapse of a certain period of time, if it is determined in step S210 that the communication bus failure flag is set, the process proceeds to step S280.

In step S280, a process is performed to check whether transmission processing is possible through the communication circuit network connected to the communication network in which the communication bus failure has occurred, and the process proceeds to step S290.

In step S290, a process is performed to check whether reception processing is possible on the communication circuit network connected to the communication network in which the communication bus failure has occurred, and the process proceeds to step S300.

In step S300, it is confirmed whether the transmission and reception processes have been performed correctly in steps S280 and S290. If the transmission and reception processes have been performed correctly, the process proceeds to step S310, and the transmission and reception processes in the non-arbitration communication method in the scheduled task are resumed. If the transmission and reception processes have not been performed correctly in step S300, the processing of the scheduled task shown in FIG. 15 is completed. Thereafter, the scheduled control process is performed periodically.

According to the seventh embodiment, in addition to being able to obtain the same effects as those of the first embodiment, when a failure occurs in non-arbitrated communication, the communication is switched to arbitrated communication, a transmission/reception check is performed to see whether non-arbitrated communication can be resumed in the communication circuit network where communication was stopped, and if transmission/reception is possible, transmission/reception is resumed. As a result, when a failure occurs in the communication circuit network using the arbitrated communication method, it becomes possible to communicate with other control devices in the non-arbitrated method.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design modifications can be made without departing from the spirit of the present invention as set forth in the claims.

10: on-vehicle control device, 20: actuator control device, 30: microcomputer, 40: communication circuit, 41: TX circuit, 42: RX circuit, 50: communication bus, 100: calculation unit, 110: communication method switching unit, 120: communication module, 130: non-arbitration communication unit, 140: arbitration communication unit, 150: fault diagnosis result unit, 200: battery, 210: power switch, 220: power circuit, 230: communication module setting unit A, 240: communication module setting unit B, 250: power switch monitor unit

Claims (9)

A plurality of communication circuits are connected to a plurality of communication buses connected to other control devices, respectively, and perform communication with the other control devices;
a plurality of communication modules connected to the plurality of communication circuits, each of which has a non-arbitration communication unit for performing communication in a non-arbitration communication method and an arbitration communication unit for performing communication in an arbitration communication method;
a communication control unit capable of switching whether each of the plurality of communication circuits communicates via the non-arbitration communication unit or the arbitration communication unit;
having
The communication control unit
When no failure occurs in the plurality of communication buses, switching is made to communication by the non-arbitration communication unit ;
When a failure occurs in any of the plurality of communication buses, switching is made so that communication is performed by the arbitration communication unit of the communication module connected to a communication circuit connected to a communication bus that is not experiencing a failure among the plurality of communication circuits ;
before starting communication by the non-arbitration communication unit and the arbitration communication unit of each of the plurality of communication modules, a non-arbitration communication function of the non-arbitration communication unit and a arbitration communication function of the arbitration communication unit are set in advance;
In the communication by the non-arbitration communication unit, a diagnostic data transmission period is set in a transmission blank period,
The communication control unit diagnoses whether a failure has occurred that prevents data from being sent or received during the diagnostic data transmission period, and switches from communication via the non-arbitration communication unit to communication via the arbitration communication unit based on the diagnosis results. The on-board control device according to claim 1 ,
An in-vehicle control device characterized in that, when the communication control unit selects communication via the non-arbitration communication unit, each of the plurality of communication modules operates exclusively for transmission processing or exclusively for reception processing. The on-board control device according to claim 1 ,
The in-vehicle control device, wherein the non-arbitration communication unit performs a transmission-only process for non-arbitration communication under a high communication bus load state. The on-board control device according to claim 1 ,
The in-vehicle control device, wherein the arbitration communication unit performs a transmission/reception process for communication by the arbitration communication unit. The on-board control device according to claim 1 ,
the communication control unit has a database in which a priority of data transmitted and received by the arbitration communication unit is set,
The vehicle-mounted control device, wherein the arbitration communication unit performs data transmission and reception processing in accordance with the priority set in the database. The on-board control device according to claim 1 ,
the communication control unit has a failure detection function for detecting a defect in the data received by the non-arbitration communication unit,
The vehicle-mounted control device, wherein the communication control unit, when detecting an error in the data received by the non-arbitration communication unit, switches communication from the non-arbitration communication unit to communication by the arbitration communication unit. The on-board control device according to claim 1 ,
Further comprising a display unit,
The communication control unit
before starting communication by the non-arbitration communication unit and the arbitration communication unit, determining whether or not data transmission and reception processing by the arbitration communication unit is normal, and when determining that the arbitration communication unit is normal, starting communication by the non-arbitration communication unit;
When it is determined that the arbitration communication unit is not normal, the display unit displays a message indicating that arbitration communication processing has not been performed correctly. The on-board control device according to claim 1 ,
The communication control unit
An in-vehicle control device characterized by diagnosing whether a failure has occurred that prevents data from being sent or received, and if a failure has occurred, switching from communication via the non-arbitration communication unit to arbitration communication via the arbitration communication unit, and after a certain period of time has elapsed, determining whether communication via the non-arbitration communication unit is possible, and if it is determined that communication via the non-arbitration communication unit is possible, resuming communication via the non-arbitration communication unit. The on-board control device according to claim 1 ,
An on-vehicle control device, characterized in that data is transmitted and received by two or more of the on-vehicle control devices.

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