Vehicle control system and abnormality diagnosis method

Abstract

To provide a vehicle control system suppressing a processing load to determine whether or not synchronization abnormality occurs.SOLUTION: A vehicle control system comprises a master ECU and an abnormality diagnosis section which determines whether or not synchronization abnormality occurs between the master ECU and a slave ECU. The abnormality diagnosis section causes the master ECU and the slave ECU to transmit and receive signals and acquires time information. The slave ECU calculates delay time in transmission based on the acquired time information. The abnormality diagnosis section: determines presence or absence of a frequency drift (S110); determines presence or absence of an offset drift based on a difference obtained by subtracting the delay time from a second time and a first time (S140) when determining the absence of the frequency drift (Yes in S110); and determines an occurrence of the synchronization abnormality (S160) when determining the presence of the frequency drift (No in S110) or when determining the presence of the offset drift (No in S140).SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] This invention relates to a vehicle control system and an abnormality diagnosis method.

Background Art

[0002] Patent Document 1 discloses an abnormality detection device that detects a deviation in time information among a plurality of devices connected via a network.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a vehicle control system, a plurality of electronic control units are interconnected by a network. In the vehicle control system, advanced vehicle control is achieved by coordinating each electronic control unit. Therefore, the vehicle control system needs to monitor whether there is an abnormality in the synchronization of time information between each electronic control unit. The process for determining such a synchronization abnormality is repeatedly executed in parallel with the vehicle control process. Therefore, it is desired to minimize the processing load.

Means for Solving the Problems

[0005] Hereinafter, the means for solving the above problems and their effects will be described. A vehicle control system for solving the above problems includes a master electronic control unit that outputs reference first-time information, and a plurality of slave electronic control units connected to the master electronic control unit via a network. This vehicle control system controls the vehicle by coordinating the master electronic control unit and the plurality of slave electronic control units. This vehicle control system includes an abnormality diagnosis unit that determines whether or not a synchronization abnormality has occurred between the first-time information and second-time information, which is time information in the slave electronic control unit. The vehicle control system transmits and receives signals between the master electronic control unit and the slave electronic control unit, and when a first signal is transmitted from the master electronic control unit to the slave electronic control unit, the first time, which is the first-time information, the second time, which is the second-time information when the slave electronic control unit receives the first signal, the third time, which is the second-time information when a second signal is transmitted from the slave electronic control unit to the master electronic control unit in response to receiving the first signal, the fourth time, which is the first-time information when the master electronic control unit receives the second signal, the fifth time, which is the first-time information when a third signal is transmitted from the master electronic control unit to the slave electronic control unit in response to receiving the second signal, and the sixth time, which is the second-time information when the slave electronic control unit receives the third signal, are obtained. Further, the vehicle control system calculates a transmission delay time between the master electronic control unit and the slave electronic control unit based on the third time, the fourth time, the fifth time, and the sixth time. Further, the abnormality diagnosis unit determines whether or not there is a cycle deviation, which is a deviation between the clock cycle in the master electronic control unit and the clock cycle in the slave electronic control unit, based on a processing cycle in the master electronic control unit, which is a difference obtained by subtracting the previously acquired first time from the first time, and a processing cycle in the slave electronic control unit, which is a difference obtained by subtracting the previously acquired second time from the second time.Further, when the abnormality diagnosis unit determines that there is no such cycle deviation, the abnormality diagnosis unit executes determining the presence or absence of an offset deviation based on the difference obtained by subtracting the delay time from the second time and the first time. Further, when the abnormality diagnosis unit determines that there is such a cycle deviation or determines that there is such an offset deviation, the abnormality diagnosis unit executes determining that the synchronization abnormality has occurred.

[0006] Further, an abnormality diagnosis method for solving the above problems is an abnormality diagnosis method in a vehicle control system that includes a master electronic control unit that outputs first time information serving as a reference, a plurality of slave electronic control units connected to the master electronic control unit via a network, and an abnormality diagnosis unit, and controls a vehicle by causing the master electronic control unit and the plurality of slave electronic control units to cooperate with each other, in which the abnormality diagnosis unit determines whether or not a synchronization abnormality has occurred between the first time information and second time information that is time information in the slave electronic control unit.

[0007] This abnormality diagnosis method includes steps of transmitting and receiving signals between the master electronic control unit and the slave electronic control unit, and obtaining a first time which is the first time information when a first signal is transmitted from the master electronic control unit to the slave electronic control unit, a second time which is the second time information when the first signal is received by the slave electronic control unit, a third time which is the second time information when a second signal is transmitted from the slave electronic control unit to the master electronic control unit in response to receiving the first signal, a fourth time which is the first time information when the second signal is received by the master electronic control unit, a fifth time which is the first time information when a third signal is transmitted from the master electronic control unit to the slave electronic control unit in response to receiving the second signal, and a sixth time which is the second time information when the third signal is received by the slave electronic control unit. Further, this abnormality diagnosis method includes a step of calculating, by the slave electronic control unit, a transmission delay time between the master electronic control unit and the slave electronic control unit based on the third time, the fourth time, the fifth time, and the sixth time. Further, this abnormality diagnosis method includes a step of determining, by the abnormality diagnosis unit, the presence or absence of a cycle deviation which is a deviation between the clock cycle of the master electronic control unit and the clock cycle of the slave electronic control unit based on a processing cycle of the master electronic control unit which is a difference obtained by subtracting the previously obtained first time from the first time, and a processing cycle of the slave electronic control unit which is a difference obtained by subtracting the previously obtained second time from the second time. Further, this abnormality diagnosis method includes a step of determining, by the abnormality diagnosis unit, the presence or absence of an offset deviation based on a difference obtained by subtracting the delay time from the second time and the first time when it is determined that there is no cycle deviation. Further, this abnormality diagnosis method includes a step of determining, by the abnormality diagnosis unit, that a synchronization abnormality has occurred when it is determined that there is a cycle deviation or when it is determined that there is an offset deviation.

[0008] The above vehicle control system can determine offset deviation without considering the influence of cycle deviation. Therefore, the calculation becomes easier. For this reason, according to the above vehicle control system, the processing load for determining whether or not a synchronization abnormality has occurred can be suppressed.

[0009] Also, according to the above abnormality diagnosis method, the processing load for determining whether or not a synchronization abnormality has occurred can be similarly suppressed.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0011] Hereinafter, an embodiment of the vehicle control system will be described with reference to FIGS. 1 to 4. FIG. 1 schematically shows the configuration of a vehicle control system 100 mounted on a vehicle such as an automobile.

[0012] <Configuration of Vehicle Control System 100> As shown in FIG. 1, the vehicle control system 100 is configured by interconnecting a plurality of electronic control units via a network. Hereinafter, the electronic control unit will be referred to as an ECU. The network in the vehicle control system 100 is, for example, Ethernet (registered trademark).

[0013] In FIG. 1, as a plurality of ECUs, a master ECU 10, a plurality of slave ECUs 20, and a validator ECU 30 are shown. Each ECU includes a processor and a memory. The memory includes a memory that stores a program executed by the processor and a memory that temporarily stores data. The vehicle control system 100 realizes advanced vehicle control by coordinating these plurality of ECUs connected via the network. Therefore, the vehicle control system 100 needs to monitor whether there is an abnormality in the synchronization of time information between each ECU. The process for determining such a synchronization abnormality is repeatedly executed in parallel with the vehicle control process.

[0014] As shown in FIG. 1, the network in the vehicle control system 100 is composed of a switch ECU 40 and a bus 50. The master ECU 10, each slave ECU 20, and the validator ECU 30 are each connected to the switch ECU 40 via the bus 50.

[0015] The master ECU 10 outputs reference first time information. Each slave ECU 20 is connected to the switch ECU 40 via the bus 50. Each slave ECU 20 obtains time information through signal exchange with the master ECU 10 and calculates the transmission delay time pDelay in the network. Then, the second time information after performing time synchronization using the delay time pDelay is output. The calculation of the delay time pDelay will be described later.

[0016] Each slave ECU 20 is an ECU that realizes various functions of the vehicle. For example, the slave ECU 20 is an engine ECU that controls the engine. The slave ECU 20 is a motor generator ECU that controls the motor generator. The slave ECU 20 is a brake ECU that controls the brake. The slave ECU 20 is a multimedia ECU that controls the car navigation system. The slave ECU 20 is a driving assistance ECU that realizes advanced driving assistance. The slave ECU 20 is a drive recorder ECU that controls the drive recorder.

[0017] The validator ECU 30 functions as an abnormality diagnosis unit that determines whether or not a synchronization abnormality has occurred between the first time information in the master ECU 10 and the second time information in the slave ECU 20.

[0018] <Diagnosis of Synchronization Abnormality> In the vehicle control system 100, signals are periodically exchanged between the master ECU 10 and the slave ECU 20, and each obtains the time information when the signal is transmitted and when the signal is received. Then, the validator ECU 30 periodically determines whether or not a synchronization abnormality has occurred between the first time information and the second time information.

[0019] <Flow of Signal Exchange for Abnormality Diagnosis> FIG. 2 is a sequence diagram showing the flow of signal exchange between each ECU related to abnormality diagnosis for determining whether or not a synchronization abnormality has occurred. The vehicle control system 100 periodically executes this sequence during operation in parallel with the processing related to vehicle control to execute an abnormality diagnosis for determining the presence or absence of a synchronization abnormality. This sequence is executed by the validator ECU 30, the master ECU 10, and each of the plurality of slave ECUs 20.

[0020] As shown in FIG. 2, in this sequence, first, the master ECU 10 transmits the first signal Sync to the slave ECU 20. The master ECU 10 acquires the first time information at the first time when the first signal Sync is transmitted as the first time t_1. As described above, the first time information is the time information that serves as a reference in vehicle control and time synchronization. And the first time information is the time information measured by the master ECU 10. The slave ECU 20 that receives the first signal Sync acquires the second time information at the second time when the first signal Sync is received as the second time t_2. Note that the second time information is the time information measured by the slave ECU 20.

[0021] Also, when the master ECU 10 transmits the first signal Sync to the slave ECU 20, it transmits the fourth signal FoUp to the slave ECU 20. Here, the time stamp of the first time t_1 is transmitted as the fourth signal FoUp. By receiving the fourth signal FoUp, the slave ECU 20 acquires the information of the first time t_1.

[0022] When receiving the first signal Sync, the slave ECU 20 transmits the second signal Req to the master ECU 10. The slave ECU 20 acquires the second time information at the second time when the second signal Req is transmitted as the third time t_3. The master ECU 10 that receives the second signal Req acquires the first time information at the first time when the second signal Req is received as the fourth time t_4.

[0023] When receiving the second signal Req, the master ECU 10 transmits the third signal Resp to the slave ECU 20. The master ECU 10 acquires the first time information at the first time when the third signal Resp is transmitted as the fifth time t_5. The slave ECU 20 that receives the third signal Resp acquires the second time information at the second time when the third signal Resp is received as the sixth time.

[0024] When the master ECU 10 sends the third signal Resp to the slave ECU 20, the master ECU 10 sends the fifth signal RespFoUp to the slave ECU 20. Here, the time stamp of the fourth time t_4 and the time stamp of the fifth time t_5 are sent as the fifth signal RespFoUp. By receiving the fifth signal RespFoUp, the slave ECU 20 acquires the information of the fourth time t_4 and the information of the fifth time t_5.

[0025] When acquiring the sixth time t_6 and receiving the fifth signal RespFoUp, the slave ECU 20 calculates the delay time pDelay. The delay time pDelay is the time of signal transmission delay between the master ECU 10 and the slave ECU 20. The slave ECU 20 calculates the delay time pDelay based on the third time t_3, the fourth time t_4, the fifth time t_5, and the sixth time t_6. Specifically, in the calculation process of the delay time pDelay, the slave ECU 20 calculates a first difference which is the difference obtained by subtracting the third time t_3 from the sixth time t_6. Also, the slave ECU 20 calculates a second difference which is the difference obtained by subtracting the fourth time t_4 from the fifth time t_5. Then, the slave ECU 20 calculates a quotient obtained by dividing the difference obtained by subtracting the second difference from the first difference by 2. This quotient is the delay time pDelay.

[0026] The master ECU 10 that has sent the fifth signal RespFoUp to the slave ECU 20 sends the master timing record message MTRM to the validator ECU 30. The master timing record message MTRM includes the sequence ID of the sent first signal Sync, the time stamp of the first time t_1, the time stamp of the fourth time t_4, and the time stamp of the fifth time t_5. Also, the master timing record message MTRM includes a self-diagnosis status indicating whether the master ECU 10 is operating normally.

[0027] The slave ECU20 that calculates the delay time pDelay transmits a slave timing record message STRM to the validator ECU30. The slave timing record message STRM includes the ID of the slave ECU20, the sequence ID of the received first signal Sync, the sequence ID of the received fourth signal FoUp, and the sequence ID of the received fifth signal RespFoUp. Further, the slave timing record message STRM includes the time stamp of the second time t_2, the time stamp of the third time t_3, and the time stamp of the sixth time t_6. Furthermore, the slave timing record message STRM includes the value of the delay time pDelay and the self-diagnosis status indicating whether the slave ECU20 is operating normally.

[0028] The validator ECU30 that has received the master timing record message MTRM and the slave timing record message STRM executes an abnormality diagnosis routine R10.

[0029] <Abnormality diagnosis routine> As shown in FIG. 3, when starting the abnormality diagnosis routine R10, the validator ECU30 first calculates a cycle deviation in the process of step S100. Specifically, the validator ECU30 calculates a third difference obtained by subtracting the first time t_1 acquired in the previous sequence execution from the first time t_1 acquired in the current sequence execution. This third difference corresponds to the processing cycle in the master ECU10. Also, the validator ECU30 calculates a fourth difference obtained by subtracting the second time t_2 acquired in the previous sequence execution from the second time t_2 acquired in the current sequence execution. This fourth difference corresponds to the processing cycle in the slave ECU20. Then, the validator ECU30 calculates the absolute value of the difference obtained by subtracting the fourth difference from the third difference. This absolute value is the value corresponding to the cycle deviation.

[0030] When the phase shift is calculated in this way, the validator ECU 30 proceeds with the process to step S110. And in the process of step S110, the validator ECU 30 determines whether there is a phase shift. Specifically, the validator ECU 30 determines that there is a phase shift when the absolute value calculated is greater than or equal to the threshold value. This threshold value is a value for determining that there is a phase shift based on the fact that the absolute value is greater than or equal to this threshold value. The magnitude of this threshold value is set based on the range that can be tolerated as the magnitude of the phase shift.

[0031] When the validator ECU 30 determines that there is a phase shift, that is, when the result of the phase shift diagnosis indicates an abnormality (step S110: NO), the process proceeds to step S160. In this case, the validator ECU 30 determines that a synchronization abnormality has occurred, and in the process of step S160, notifies the master ECU 10 and each slave ECU 20 that a synchronization abnormality has occurred. As shown in FIG. 2, the validator ECU 30 transmits a notification message NM to the master ECU 10 and each slave ECU 20 in this abnormality diagnosis routine R10. The notification message NM is a message for notifying the result of the abnormality diagnosis by the validator ECU 30. The notification message NM includes information indicating the state of the master ECU 10 and information on the presence or absence of a synchronization abnormality with each slave ECU 20. That is, in the process of step S160, the validator ECU 30 transmits a notification message NM including information indicating that a synchronization abnormality has occurred between the master ECU 10 and the slave ECU 20 to the master ECU 10 and each slave ECU 20.

[0032] On the other hand, when the validator ECU 30 determines that there is no cycle deviation, that is, when the result of the cycle deviation diagnosis indicates normality (step S110: YES), the process proceeds to step S130. Then, in the process of step S130, the validator ECU 30 calculates the offset between the first time information and the second time information. Specifically, the validator ECU 30 calculates the fifth difference obtained by subtracting the delay time pDelay from the second time t_2. Then, the validator ECU 30 calculates the absolute value of the difference obtained by subtracting this fifth difference from the first time t_1. This absolute value is the offset.

[0033] After calculating the offset in this way, the validator ECU 30 proceeds to step S140. Then, in the process of step S140, the validator ECU 30 determines the presence or absence of an offset deviation. Specifically, the validator ECU 30 determines that there is an offset deviation when the calculated offset value is equal to or greater than the threshold value. This threshold value is a value for determining that there is an offset deviation based on the fact that the offset value is equal to or greater than this threshold value. The magnitude of this threshold value is set based on the range that can be tolerated as the magnitude of the offset deviation.

[0034] When the validator ECU 30 determines that there is an offset deviation, that is, when the result of the offset deviation diagnosis indicates abnormality (step S140: NO), the process proceeds to step S160. Also in this case, the validator ECU 30 determines that a synchronization abnormality has occurred, and in the process of step S160, notifies the master ECU 10 and each slave ECU 20 that a synchronization abnormality has occurred. That is, the validator ECU 30 transmits a notification message NM including information indicating that a synchronization abnormality has occurred between the master ECU 10 and the slave ECU 20 to the master ECU 10 and each slave ECU 20.

[0035] On the other hand, when the validator ECU 30 determines that there is no offset shift, that is, when the result of the offset shift diagnosis indicates normality (step S140: YES), the process proceeds to step S150. In this case, the validator ECU 30 determines that no synchronization anomaly has occurred, and in the process of step S150, notifies the master ECU 10 and each slave ECU 20 that no synchronization anomaly has occurred. That is, the validator ECU 30 transmits a notification message NM including information indicating that no synchronization anomaly has occurred between the master ECU 10 and the slave ECU 20 to the master ECU 10 and each slave ECU 20.

[0036] After transmitting the notification message NM to the master ECU 10 and each slave ECU 20 through the process of step S150 or the process of step S160 in this way, the validator ECU 30 temporarily ends this routine.

[0037] In the vehicle control system 100, in this way, the presence or absence of a synchronization anomaly is monitored by repeatedly executing the sequence shown in FIG. 2. <Frame Format> FIG. 4 schematically shows the format of a frame 200 used for data communication between the validator ECU 30 and the master ECU 10 and for data communication between the validator ECU 30 and each slave ECU 20. The master timing record message MTRM, the slave timing record message STRM, and the notification message NM are transmitted by the frame 200 according to this format.

[0038] As shown in FIG. 4, the frame 200 includes a first field 60 and a second field 70. Information such as an IP address and a UDP header is stored in the first field 60. The second field 70 is divided into a PDU header 71 and a PDU payload 75. Further, the PDU payload 75 is divided into a common field 76 and an individual field 77.

[0039] The master timing record message MTRM is a frame 200 that stores in the individual field 77 the sequence ID of the first transmitted signal Sync, the timestamp of the first time t_1, the timestamp of the fourth time t_4, and the timestamp of the fifth time t_5.

[0040] The slave timing record message STRM is a frame 200 that stores the following information in the individual field 77. · The ID of the slave ECU20, the sequence ID of the received first signal Sync, the sequence ID of the fourth signal FoUp, and the sequence ID of the fifth signal RespFoUp.

[0041] · The timestamp of the second time t_2, the timestamp of the third time t_3, and the timestamp of the sixth time t_6. · The value of the delay time pDelay and the self-diagnosis status indicating whether the slave ECU20 is operating normally.

[0042] And the notification message NM is a frame 200 that stores in the individual field 77 the information indicating the state of the master ECU10 and the information on the presence or absence of synchronization anomalies between each slave ECU20.

[0043] <Operation of this Embodiment> Synchronization anomalies may occur due to the overlap of cycle deviation and offset deviation. Note that cycle deviation is the deviation between the clock cycle in the master ECU10 and the clock cycle in the slave ECU20. And offset deviation is the offset between the first time information and the second time information that occurs even when the clock cycles are aligned. That is, offset deviation is the deviation between the execution timing of the process in the master ECU10 and the execution timing of the process in the slave ECU20 excluding the deviation of the clock cycle.

[0044] In the above-described vehicle control system 100, after determining that there is no cycle deviation, the validator ECU 30 determines the presence or absence of offset deviation using the fifth difference obtained by subtracting the delay time pDelay from the second time t_2. The fifth difference obtained by subtracting the delay time pDelay from the second time t_2 should be equal to the value of the first time t_1 when there is no cycle deviation or offset deviation and no synchronization abnormality occurs.

[0045] After determining that there is no cycle deviation, the validator ECU 30 determines the presence or absence of offset deviation based on the fifth difference and the first time t_1. That is, with this calculation method, it is not necessary to consider the influence of cycle deviation in determining the presence or absence of offset deviation.

[0046] In this way, the vehicle control system 100 first executes the determination of the presence or absence of cycle deviation, and after determining that there is no cycle deviation, determines the presence or absence of offset deviation. Then, when the validator ECU 30 determines that there is a cycle deviation or determines that there is an offset deviation, it determines that a synchronization abnormality has occurred.

[0047] <Effect of this Embodiment> (1) The vehicle control system 100 can determine the offset deviation without considering the influence of cycle deviation. Therefore, the calculation becomes easy. Therefore, according to the vehicle control system 100, the processing load for determining whether a synchronization abnormality has occurred can be suppressed.

[0048] (2) As shown in FIG. 2, the vehicle control system 100 executes a step of transmitting and receiving signals between the master ECU 10 and the slave ECU 20 to obtain the first time t_1 to the sixth time t_6. Then, the slave ECU 20 executes a step of calculating the transmission delay time pDelay between the master ECU 10 and the slave ECU 20 based on the third time t_3, the fourth time t_4, the fifth time t_5, and the sixth time t_6.

[0049] The validator ECU 30 executes a step of determining the presence or absence of a cycle deviation, which is the deviation between the clock cycle in the master ECU 10 and the clock cycle in the slave ECU 20, based on the third difference and the fourth difference (step S110).

[0050] Then, when the validator ECU 30 determines that there is no cycle deviation (step S120: YES), it executes a step of determining the presence or absence of an offset deviation based on the fifth difference and the first time t_1 (step S140).

[0051] Then, when the validator ECU 30 determines that there is a cycle deviation (step S110: NO) or determines that there is an offset deviation (step S140: NO), it executes a step of determining that a synchronization abnormality has occurred (step S160).

[0052] According to such an abnormality diagnosis method, the processing load for determining whether a synchronization abnormality has occurred as described in (1) can be suppressed. (3) The slave ECU 20 calculates a first difference obtained by subtracting the third time t_3 from the sixth time t_6 and a second difference obtained by subtracting the fourth time t_4 from the fifth time t_5. Then, the slave ECU 20 calculates the quotient obtained by dividing the difference obtained by subtracting the second difference from the first difference by 2 as the delay time pDelay. The vehicle control system 100 can thus calculate the delay time pDelay.

[0053] (4) The validator ECU 30 determines that there is a cycle deviation when the absolute value of the difference obtained by subtracting the fourth difference from the third difference is greater than or equal to a threshold value. Thereby, the validator ECU 30 can determine that there is a cycle deviation when the deviation between the third difference obtained by subtracting the previously acquired first time t_1 from the first time t_1 and the fourth difference obtained by subtracting the previously acquired second time t_2 from the second time t_2 is greater than or equal to a predetermined level.

[0054] (5) When the absolute value of the difference obtained by subtracting the fifth difference from the first time t_1 is greater than or equal to the threshold value, the slave ECU 20 determines that there is an offset deviation. Thereby, the validator ECU 30 can determine that there is an offset deviation when the deviation between the fifth difference obtained by subtracting the delay time pDelay from the second time t_2 and the first time t_1 is greater than or equal to a predetermined level.

[0055] <Modified Example> This embodiment can be implemented with the following modifications. This embodiment and the following modified examples can be implemented in combination with each other as long as they do not technically conflict.

[0056] · In the above embodiment, an example in which the master ECU 10, each slave ECU 20, and the validator ECU 30 are connected to the switch ECU 40 via the bus 50 is shown. The configuration of the vehicle control system 100 is not limited to such a configuration.

[0057] For example, as shown in FIG. 5, the vehicle control system 100 may have a configuration in which the master ECU 10 includes a time master unit 11 and a switch unit 14. The time master unit 11 is, for example, a virtual machine configured on the master ECU 10 and is a functional unit that functions in the same manner as the master ECU 10 in the above embodiment. Further, the switch unit 14 is a virtual machine configured on the master ECU 10 and is a functional unit that functions in the same manner as the switch ECU 40 in the above embodiment.

[0058] Also, as shown in FIG. 6, the vehicle control system 100 may have a configuration in which the master ECU 10 includes a time master unit 11, a switch unit 14, and a validator unit 13. The validator unit 13 is, for example, a virtual machine configured on the master ECU 10 and is a functional unit that functions in the same manner as the validator ECU 30 in the above embodiment.

[0059] Even when these configurations are adopted, the same effects as those of the above embodiment can be obtained. ·In the above embodiment, an example was shown in which it was determined that there was a cycle deviation based on the fact that the absolute value of the difference obtained by subtracting the fourth difference from the third difference was equal to or greater than the threshold value. In contrast, the cycle deviation determination method may be any method that determines that there is a cycle deviation when the deviation between the processing cycle in the master ECU 10 and the processing cycle in the slave ECU 20 is equal to or greater than a predetermined level. Therefore, the cycle deviation determination method is not limited to the method exemplified in the above embodiment. For example, a method may be adopted in which it is determined that there is a cycle deviation based on the fact that the value of the ratio of the third difference to the fourth difference does not fall within an allowable range centered on 1.0.

[0060] ·In the above embodiment, an example was shown in which it was determined that there was an offset deviation based on the fact that the absolute value of the difference obtained by subtracting the fifth difference from the first time t_1 was equal to or greater than the threshold value. In contrast, the offset deviation determination method may be any method that determines that there is an offset deviation when the deviation between the fifth difference obtained by subtracting the delay time pDelay from the second time t_2 and the first time t_1 is equal to or greater than a predetermined level. Therefore, the offset deviation determination method is not limited to the method exemplified in the above embodiment. For example, a method may be adopted in which it is determined that there is an offset deviation based on the fact that the value of the ratio of the first time t_1 to the fifth difference does not fall within an allowable range centered on 1.0.

Explanation of Signs

[0061] 10…Master ECU, 11…Time master unit, 13…Validator unit, 14…Switch unit, 20…Slave ECU, 30…Validator ECU, 60…First field, 70…Second field, 71…PDU header, 75…PDU payload, 76…Common field, 77…Individual field, 100…Vehicle control system, 200…Frame

Claims

1. A vehicle control system comprising: a master electronic control unit that outputs reference first time information; and a plurality of slave electronic control units connected to the master electronic control unit via a network, wherein the master electronic control unit and the plurality of slave electronic control units cooperate to control a vehicle, further comprising an abnormality diagnosis unit that determines whether or not a synchronization abnormality has occurred between the first time information and second time information which is time information in the slave electronic control unit, wherein the slave electronic control unit, sends and receives signals between the master electronic control unit and the slave electronic control unit, and obtains a first time which is the first time information when a first signal is sent from the master electronic control unit to the slave electronic control unit, a second time which is the second time information when the first signal is received by the slave electronic control unit, a third time which is the second time information when a second signal is sent from the slave electronic control unit to the master electronic control unit in response to receiving the first signal, a fourth time which is the first time information when the second signal is received by the master electronic control unit, a fifth time which is the first time information when a third signal is sent from the master electronic control unit to the slave electronic control unit in response to receiving the second signal, and a sixth time which is the second time information when the third signal is received by the slave electronic control unit, calculates a transmission delay time between the master electronic control unit and the slave electronic control unit based on the third time, the fourth time, the fifth time, and the sixth time, wherein the abnormality diagnosis unit, determines whether there is a cycle deviation which is a deviation between the clock cycle in the master electronic control unit and the clock cycle in the slave electronic control unit based on a processing cycle in the master electronic control unit which is a difference obtained by subtracting the previously acquired first time from the first time, and a processing cycle in the slave electronic control unit which is a difference obtained by subtracting the previously acquired second time from the second time, and determines whether there is an offset deviation based on a difference obtained by subtracting the delay time from the second time and the first time only when it is determined that there is no cycle deviation. When it is determined that there is a cycle deviation or when it is determined that there is an offset deviation, determining that the synchronization abnormality has occurred, and executing the determination Vehicle control system

2. The slave electronic control unit calculates the quotient obtained by dividing by 2 the difference obtained by subtracting the second difference obtained by subtracting the fourth time from the fifth time from the first difference obtained by subtracting the third time from the sixth time as the delay time The vehicle control system according to claim 1

3. The abnormality diagnosis unit determines that there is a cycle deviation when the deviation between the cycle of the process in the master electronic control unit, which is the difference obtained by subtracting the previously acquired first time from the first time, and the cycle of the process in the slave electronic control unit, which is the difference obtained by subtracting the previously acquired second time from the second time, is equal to or greater than a predetermined level The vehicle control system according to claim 1

4. The abnormality diagnosis unit determines that there is an offset deviation when the deviation between the difference obtained by subtracting the delay time from the second time and the first time is equal to or greater than a predetermined level The vehicle control system according to claim 1

5. An abnormality diagnosis method in a vehicle control system including a master electronic control unit that outputs first time information as a reference, a plurality of slave electronic control units connected to the master electronic control unit via a network, and an abnormality diagnosis unit, and controlling the vehicle by coordinating the master electronic control unit and the plurality of slave electronic control units, wherein the abnormality diagnosis unit determines whether or not a synchronization abnormality has occurred between the first time information and second time information that is time information in the slave electronic control unit Transmit and receive signals between the master electronic control unit and the slave electronic control unit, and the first time which is the first time information when the first signal is transmitted from the master electronic control unit to the slave electronic control unit, the second time which is the second time information when the slave electronic control unit receives the first signal, the third time which is the second time information when the slave electronic control unit transmits a second signal to the master electronic control unit in response to receiving the first signal, the fourth time which is the first time information when the master electronic control unit receives the second signal, the fifth time which is the first time information when the master electronic control unit transmits a third signal to the slave electronic control unit in response to receiving the second signal, and the sixth time which is the second time information when the slave electronic control unit receives the third signal, and the slave electronic control unit obtains them; The slave electronic control unit calculates the transmission delay time between the master electronic control unit and the slave electronic control unit based on the third time, the fourth time, the fifth time, and the sixth time; Based on the cycle of processing in the master electronic control unit which is the difference obtained by subtracting the previously acquired first time from the first time, and the cycle of processing in the slave electronic control unit which is the difference obtained by subtracting the previously acquired second time from the second time, the abnormality diagnosis unit determines the presence or absence of the cycle deviation which is the deviation between the clock cycle in the master electronic control unit and the clock cycle in the slave electronic control unit; Only when it is determined that there is no cycle deviation, based on the difference obtained by subtracting the delay time from the second time and the first time, the abnormality diagnosis unit determines the presence or absence of offset deviation; When it is determined that there is a cycle deviation or when it is determined that there is an offset deviation, the abnormality diagnosis unit determines that the synchronization abnormality has occurred; Abnormality diagnosis method.

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