JP2016190574A - Diagnosis device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a diagnosis device which can specify a cause of abnormality easily.SOLUTION: A diagnosis device includes a structure for detecting abnormality by carrying out normal communication between a diagnosis object unit 2-1 and a reference unit 2-3 through a first CAN bus 2-29, and in addition, the diagnosis object unit includes a diagnosis data storage part 2-8, a reference data storage part 2-6, a comparison operation part 2-7, and a diagnosis result storage part 2-9 to achieve a diagnosis function. The diagnosis data storage part reads and stores diagnosis data transmitted from the reference unit by diagnosis communication with its own clock. The reference data storage part stores the predetermined reference data. The comparison operation part compares the diagnosis data read from the diagnosis data storage part and the reference data read from the reference data storage part. A diagnosis result obtained by the comparison is stored in the diagnosis result storage part.SELECTED DRAWING: Figure 1

Description

The present invention relates to a diagnostic apparatus for diagnosing the presence or absence of a communication abnormality inside a vehicle, for example.

  Conventionally, in a diagnostic apparatus using a CAN (Controller Area Network) as one of in-vehicle networks, a first unit and a second unit are connected by a CAN bus. When data is periodically transmitted from the first unit to the second unit, the data is divided into control data and the content of a transmission number counter (CAN PRUN (Program RUNning) signal). The first unit increments the content of the transmission number counter every time data is transmitted.

  The second unit determines whether or not the transmission number counter is normally incremented every time data is received. If the increment is not normal twice consecutively, it is determined that the system is abnormal. Further, the communication interruption is detected by determining whether the CAN PRUN signal has been normally received.

Japanese Patent Application Laid-Open No. 2000-156665

  As described above, in the conventional technique, a signal line abnormality such as communication interruption and an increment abnormality caused by internal hardware are not distinguished, and are detected as one defect. Therefore, for example, in the case of a temporary abnormality in which an abnormal state such as a clock shift does not continue, there is a problem that it takes time to reproduce the abnormality and it takes time to specify the cause.

  The subject of this invention is providing the diagnostic apparatus which can pinpoint the cause of abnormality easily.

  In order to solve the above-described problem, the diagnostic device according to the present invention realizes a diagnostic function in addition to a configuration in which an abnormality is detected by performing normal communication between the diagnostic target unit and the reference unit via the first CAN bus. The following configuration is provided. That is, the diagnosis target unit described above includes a diagnosis data storage unit, a first reference data storage unit, a comparison operation unit, and a diagnosis result storage unit. The diagnostic data storage unit reads and stores diagnostic data transmitted from the reference unit by diagnostic communication using its own clock. The first reference data storage unit stores predetermined reference data. The comparison operation unit compares the diagnostic data read from the diagnostic data storage unit with the reference data read from the first reference data storage unit. The diagnosis result obtained by the comparison by the comparison operation unit is stored in the diagnosis result storage unit.

  According to the present invention, the diagnosis target unit detects the presence or absence of abnormality by reading the diagnostic data transmitted from the reference unit by diagnostic communication with its own clock and comparing it with predetermined reference data. Therefore, it is possible to provide a diagnostic device that can easily identify the cause of the abnormality.

It is a figure which shows the structure of the diagnostic apparatus which concerns on Example 1 of this invention. It is a flowchart which shows operation | movement of the diagnostic target unit of the diagnostic apparatus which concerns on Example 1 of this invention. It is a flowchart which shows operation | movement of the reference | standard unit of the diagnostic apparatus which concerns on Example 1 of this invention. It is a figure for demonstrating operation | movement of the diagnostic apparatus which concerns on Example 1 of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram illustrating the configuration of the diagnostic apparatus according to the first embodiment of the present invention. This diagnostic apparatus includes two buses such as a first CAN bus 2-29 and a second CAN bus 2-30, and a diagnosis target unit (first ECU) 2-1 and a reference unit (third ECU) 2-3 have these two systems. Are connected by a CAN bus. The first CAN bus 2-29 is used to perform normal communication (communication other than diagnostic communication), and the second CAN bus 2-30 is used to perform diagnostic communication.

  FIG. 1 shows an example in which another unit (second ECU) 2-2 is connected to the first CAN bus 2-29, but this shows an example in which a conventional unit is used in combination. The other unit 2-2 is not directly related to the present invention. Therefore, the description of the unit 2-2 is omitted below.

  Next, the internal configuration of each of the diagnosis target unit 2-1 and the reference unit 2-3 will be described. Each unit is roughly divided into two functions such as “conventional function” and “diagnostic function according to the present invention (hereinafter simply referred to as“ diagnostic function ”).

  First, the part which implement | achieves a conventional function is demonstrated. The part that realizes the conventional function of the diagnosis target unit 2-1 includes a diagnosis unit 2-13 and a transceiver 2-16. The transceiver 2-16 controls transmission / reception of signals between the first CAN bus 2-29 and the diagnosis unit 2-13. The diagnosis unit 2-13 includes a signal detection unit 2-14 and an increment diagnosis unit 2-15. The signal detection unit 2-14 detects whether a signal received from the first CAN bus 2-29 via the transceiver 2-16 has been interrupted. The increment diagnosis unit 2-15 increments the content of a transmission number counter (not shown) every time data is transmitted, and sends the result to the first CAN bus 2-29 via the transceiver 2-16.

  The part that realizes the conventional function of the reference unit 2-3 includes a diagnosis unit 2-25 and a transceiver 2-28, as with the diagnosis target unit 2-1. The transceiver 2-28 controls transmission / reception of signals between the first CAN bus 2-29 and the diagnosis unit 2-25. The diagnosis unit 2-25 includes a signal detection unit 2-26 and an increment diagnosis unit 2-27. The signal detection unit 2-26 detects whether a signal received from the first CAN bus 2-29 via the transceiver 2-28 has been interrupted. The increment diagnosis unit 2-27 increments the content of a transmission number counter (not shown) every time data is transmitted, and sends the result to the first CAN bus 2-29 via the transceiver 2-28.

  Next, the part which implement | achieves a diagnostic function is demonstrated. First, the part which implement | achieves the diagnostic function of the diagnostic object unit 2-1 is demonstrated. The part for realizing the diagnosis function of the diagnosis target unit 2-1 includes a transceiver 2-4, a calculation unit 2-5, and a data request unit 2-10.

  The transceiver 2-4 controls transmission / reception of data between the second CAN bus 2-30, the arithmetic unit 2-5, and the data request unit 2-10.

  The data request unit 2-10 requests the reference unit 2-3 to transmit diagnostic data via the transceiver 2-4 and the second CAN bus 2-30 when diagnostic data is needed.

  The calculation unit 2-5 includes a reference data storage unit 2-6, a comparison calculation unit 2-7, a diagnostic data storage unit 2-8, a diagnostic result storage unit 2-9, a reference data time storage unit 2-11, and diagnostic data reception A time storage unit 2-12 is provided.

  The reference data storage unit 2-6 corresponds to the first reference data storage unit of the present invention, and stores the same reference data stored in advance in the reference data storage unit 2-24 of the reference unit 2-3. Yes. The reference data stored in the reference data storage unit 2-6 is read out by the comparison operation unit 2-7 and subjected to comparison operation.

  The diagnostic data storage unit 2-8 stores diagnostic data received from the reference unit 2-3 via the second CAN bus 2-30 and the transceiver 2-4. The diagnostic data stored in the diagnostic data storage unit 2-8 is read out by the comparison calculation unit 2-7 and subjected to comparison calculation.

  The reference data time storage unit 2-11 stores a reference data time t2, which is known data indicating the time required for normal transmission / reception with the reference unit 2-3.

  The diagnostic data reception time storage unit 2-12 stores the diagnostic data reception time t1 received from the reference unit 2-3 via the second CAN bus 2-30 and the transceiver 2-4.

  The comparison operation unit 2-7 compares the reference data read from the reference data storage unit 2-6 with the diagnostic data read from the diagnostic data storage unit 2-8. Further, the comparison calculation unit 2-7 compares the reference data time t2 read from the reference data time storage unit 2-11 with the diagnostic data reception time t1 read from the diagnostic data reception time storage unit 2-12. These comparison results are sent to the diagnostic result storage unit 2-9.

  The diagnosis result storage unit 2-9 is the result obtained by the comparison by the comparison operation unit 2-7, that is, the reference data read from the reference data storage unit 2-6 and the diagnosis data read from the diagnosis data storage unit 2-8. The diagnosis result obtained by comparison with is stored. The diagnosis result storage unit 2-9 stores a comparison result between the reference data time t2 read from the reference data time storage unit 2-11 and the diagnosis data reception time t1 read from the diagnosis data reception time storage unit 2-12.

  Next, the part which implement | achieves the diagnostic function of the reference | standard unit 2-3 is demonstrated. The part that implements this diagnostic function includes a transceiver 2-21 and a reference data transmission unit 2-22.

  The transceiver 2-21 controls data transmission / reception between the second CAN bus 2-30 and the reference data transmission unit 2-22. The reference data transmission unit 2-22 includes a signal generation unit 2-23 and a reference data storage unit 2-24.

  The signal generation unit 2-23 receives the reference data stored in the reference data storage unit 24 in response to a diagnosis data transmission request (diagnosis request) received from the second CAN bus 2-30 via the transceiver 2-21. Generate diagnostic data based on The diagnostic data generated by the signal generator 2-23 is transmitted to the diagnostic target unit 2-1 via the transceiver 2-21 and the second CAN bus 2-30.

  The reference data storage unit 2-24 corresponds to the second reference data storage unit of the present invention, and stores reference data used for generating diagnostic data. As described above, the reference data stored in the reference data storage unit 2-24 is read out by the signal generation unit 2-23 and used to generate diagnostic data.

  Next, the diagnostic operation of the diagnostic apparatus configured as described above will be described with reference to the flowcharts shown in FIGS. As shown in FIG. 2, in this diagnostic apparatus, the following three diagnoses are roughly divided.

  The first is “second CAN bus disruption diagnosis” for diagnosing whether or not communication is established by the second CAN bus 2-30 for diagnosis. The second is “clock abnormality diagnosis” for diagnosing a clock shift, which is one of abnormalities in which an abnormal state does not continue. The third is “conventional diagnosis” that has been conventionally performed, such as incremental diagnosis using the CAN PRUN signal.

  When the ignition key is turned on at the time of starting the vehicle, etc., it starts from the first diagnosis “second CAN bus disruption diagnosis”, followed by “clock abnormality diagnosis” and “conventional diagnosis” in order, for example, the ignition key is turned off. Each of these diagnoses is repeated until done.

Next, details of each diagnosis will be described. First, the “second CAN bus disruption diagnosis” will be described.
The second CAN bus disruption diagnosis is triggered by turning on the ignition key. When the second CAN bus interruption diagnosis is started, first, diagnosis data is requested to the reference unit (step S11). That is, the data request unit 2-10 of the diagnosis target unit 2-1 requests the reference unit 2-3 to transmit diagnostic data via the transceiver 2-4 and the second CAN bus 2-30.

  As shown in FIG. 3, the reference unit 2-3 receives a request for diagnostic data (step S31). That is, the reference unit 2-3 receives a request for diagnostic data sent from the diagnosis target unit 2-1. Next, the reference data is read (step S32). That is, the signal generation unit 2-23 reads the reference data serving as diagnostic data from the reference data storage unit 2-24.

  Next, diagnostic data is transmitted (step S33). That is, the signal generator 2-23 generates diagnostic data from the reference data read in step S32, and transmits the diagnostic data to the diagnostic target unit 2-1 via the transceiver 2-21 and the second CAN bus 2-30. Next, a timer is started (step S34). That is, in the reference unit 2-3, a timer (not shown) is started when diagnostic data is transmitted.

  On the other hand, as shown in FIG. 2, the diagnostic target unit 2-1 starts receiving diagnostic data (step S12). That is, the diagnosis target unit 2-1 starts receiving the diagnostic data sent from the reference unit 2-3 in response to the diagnostic data transmission request.

  Next, it is checked whether or not communication is established (step S13). That is, the diagnosis target unit 2-1 checks whether diagnosis data is received from the reference unit 2-3. If it is determined in step S13 that communication is not established, the content i of the NG counter is updated (step S14). That is, the content i of the NG counter is incremented (i = i + 1).

  Next, it is checked whether or not the content i of the NG counter is 5 or more (step S15). If it is determined in step S15 that the content i of the NG counter is 5 or more, it is determined that the communication of the second CAN bus 2-30 has been interrupted (step S16). That is, if communication is not established five times in succession, it is determined that diagnostic data has not been received for a certain period of time, it is determined that communication on the second CAN bus 2-30 has been interrupted, and the process ends.

  On the other hand, if it is determined in step S15 that the content i of the NG counter is not 5 or more, the process returns to step S11, and again from the diagnosis target unit 2-1 to the reference unit 2-3. A request for diagnostic data is made. Similarly, the diagnosis target unit 2-1 starts re-reception of the diagnosis data and checks again whether or not communication is established.

  On the other hand, in the reference unit 2-3, as shown in FIG. 3, after the timer is started (step S34), it is checked whether there is a re-request (step S35). If it is determined in step S35 that there is a re-request, the timer is reset (step S36). Thereafter, the process returns to step S32, and the above-described diagnosis data is transmitted.

  The above processing is the “second CAN bus interruption diagnosis”, and if it is determined that the second CAN bus interruption diagnosis is normal, the process proceeds to “clock abnormality diagnosis” in the next step.

  Next, “clock abnormality diagnosis” will be described. If it is determined in step S13 in FIG. 2 that communication has been established, a reception completion flag is transmitted (step S17). That is, the diagnosis target unit 2-1 transmits a reception completion flag to the reference unit 2-3 when receiving the diagnosis data.

  As shown in FIG. 3, the reference unit 2-3 receives a diagnostic data reception completion flag when it is determined in step S35 that there is no re-request (step S37). That is, the reference unit 2-3 receives the reception completion flag from the diagnosis target unit 2-1. Next, the timer is stopped (step S38). That is, the timer that was started when the diagnostic data was transmitted is stopped.

  Next, the diagnostic data reception time is calculated (step S39). That is, the signal generation unit 2-23 of the reference data transmission unit 2-22 calculates a diagnostic data reception time t1, which is a time required from its own transmission to reception by the other party. Next, the diagnostic data reception time is transmitted (step S40). That is, the signal generator 2-23 transmits the diagnosis data reception time t1 calculated in step S39 to the diagnosis target unit 2-1 via the transceiver 2-21 and the second CAN bus 2-30. Thereafter, the process returns to step S32.

  In the diagnosis target unit 2-1, as shown in FIG. 2, after the reception completion flag is transmitted in step S17, the received diagnostic data is recorded (step S18). That is, the diagnosis target unit 2-1 stores the received diagnosis data in the diagnosis data storage unit 2-8. Next, the diagnostic data reception time t1 is received (step S19). That is, the diagnosis target unit 2-1 receives the diagnosis data reception time t1 transmitted from the reference unit 2-3.

  Next, the diagnostic data reception time t1 is recorded (step S20). That is, the diagnosis target unit 2-1 records the received diagnosis data reception time t1 in the diagnosis data reception time storage unit 2-12. Next, the reference data time t2 is read (step S21). That is, the reference data time t2, which is known data indicating the time required for normal transmission / reception, is read from the reference data time storage unit 2-11.

  Next, it is checked whether or not the diagnostic data reception time t1 matches the reference data time t2 (step S22). If it is determined that they do not match, it is determined that the stationary clock system is abnormal (step S23). That is, since the time required for transmission / reception is equal to or longer than the prescribed time (reference data time t2), it is diagnosed that the diagnosis target unit 2-1 itself has a steady clock deviation, and the diagnosis result is stored in the diagnosis result storage unit 2-9. To be recorded. Thereafter, the process ends.

  If the diagnosis data reception time t1 and the reference data time t2 match in step S22, it is next checked whether or not the diagnosis data and reference data match (step S24). That is, the comparison calculation unit 2-7 reads out the diagnostic data recorded in the diagnostic data storage unit 2-8 and the reference data recorded in the reference data storage unit 2-6, and whether or not they match. Check out. If it is determined in step S24 that they do not match, it is determined that there is a sudden clock system abnormality (step S25). That is, although the diagnostic data is received at the specified time, the data does not match, so it is determined that a data misreading due to a sudden clock abnormality has occurred, and this is stored in the diagnostic result storage unit 2-9. Is recorded. Thereafter, the process ends.

  Note that the reference data storage unit 2-24 stores reference data that can vary the section that is not synchronized with the abnormal level of the clock to be detected. This reference data is diagnostic data that can vary the period of non-synchronization as indicated by reference numerals 5-1 and 5-2 in FIG. For example, when maximizing the non-synchronized period in CAN, there are two CAN communication rules: “synchronize at falling (1 → 0)” and “insert inverted bit when 5 bits of the same data continue” Considering the rule, “0000011111” is obtained.

  As an example, in the case of diagnostic data in which the period of non-synchronization as indicated by reference numeral 5-1 in FIG. 4A is maximum when the clock deviation is small, as indicated by reference numeral 5-2 in FIG. Deviations in the data reading timing of the diagnosis target unit 2-1 are accumulated without being corrected. As a result, as indicated by reference numeral 5-3 in FIG. 4A, the diagnostic data received by the diagnostic target unit 2-1 does not match the diagnostic data transmitted by the reference unit 2-3. A minute clock abnormality can be detected in the data content comparison diagnosis described above. In this way, the detection accuracy can be increased by using the data that maximizes the period of non-synchronization.

  Further, in the diagnosis data having a short period of non-synchronization as indicated by reference numeral 5-4 in FIG. 4B, the data reading timing of the diagnostic target unit is shifted as shown in reference numeral 5-5 in FIG. The deviation is corrected each time As indicated by reference numeral 5-6 in FIG. 4B, the diagnostic data received by the diagnostic target unit 2-1 coincides with the diagnostic data transmitted by the reference unit 2-3 as a result, and the clock abnormality cannot be detected. However, it is possible to know how much of the clock is abnormal by gradually increasing the period of not synchronizing and referring to the period of not synchronizing the diagnostic data when detecting the clock abnormality.

  If it is determined in step S24 described above that they match, it is determined that the clock is normal and the process proceeds to “conventional diagnosis”. In the conventional diagnosis, processing similar to the processing described in the background art section is executed. In the following, the same processes as those described in the background art column will be described with the same reference numerals used in the flowchart of FIG. First, it is checked whether or not the CAN PRUN signal has been normally received (step S51). Here, if it is determined that the signal is not normally received, it is determined that the communication interruption of the first CAN bus 2-29 has been detected (step S52). Thereafter, the process ends.

  On the other hand, if it is determined in step S51 that the signal has been normally received, it is next checked whether there is an increment abnormality (step S53). If it is determined that there is no increment abnormality, it is determined that the communication system is normal (step S54). Next, the content n of the NG counter is initialized to 0 (step S55), and then the process returns to step S51.

  On the other hand, if it is determined in step S53 that there is an increment abnormality, the content n of the NG counter is updated (n + 1) (step S56). Next, it is checked whether or not the content n of the NG counter is 2 or more (step S57). If it is determined that n is not 2 or more, the processing of step S11 is executed to execute the CAN bus interruption diagnosis again. Return. On the other hand, if it is determined in step S57 that the number is 2 or more, it is recognized that the increment has not been normally performed twice consecutively, and it is determined that the system is abnormal (step S58).

  As described above, by performing the clock abnormality diagnosis in addition to the conventional diagnosis, it is possible to easily and quickly detect an abnormality such as a clock shift and the like in which an abnormal state does not continue and communication returns to normal. . As a result, it is possible to perform a diagnosis that is stronger than the conventional diagnosis, and it is possible to improve reliability and maintainability.

  In addition, the reference unit 2-3 stores the same reference data as the reference data stored in the diagnosis target unit 2-1, and generates diagnosis data in response to a request from the diagnosis target unit 2-1. Transmit to unit 2-1. Thereby, it becomes easy to identify a unit that is an abnormal diagnosis target.

  Moreover, since the conventional diagnostic apparatus performs abnormality diagnosis between units connected to one CAN bus, it cannot identify a faulty part. In the diagnosis apparatus according to the first embodiment, the second CAN bus 2-30 with a guaranteed wiring system is used, and a diagnosis different from the diagnosis using the conventional first CAN bus 2-29 is performed. The status check can be simplified and maintainability is improved.

  In the diagnostic apparatus according to the first embodiment, the reference data stored in the reference data storage unit 2-24 can vary the interval in which synchronization is not achieved according to the level of the clock abnormality to be detected. This makes it possible to detect an abnormality such as a clock shift that does not continue the abnormal state and returns to normal communication.

  Furthermore, in the diagnosis apparatus according to the first embodiment, the time required for receiving the diagnosis time in the diagnosis target unit 2-1 matches the time required for reception (reference data time) stored in advance or received. Check whether the diagnostic data matches the stored reference data. As a result, it is possible to detect a steady clock abnormality or a sudden clock abnormality that always shifts.

  In the first embodiment, the case where there is one diagnosis target unit has been described. However, if the same configuration as that for realizing the diagnosis function of the diagnosis target unit is provided, a plurality of diagnosis target units can be provided. Can also be applied.

  Moreover, when performing the above-mentioned diagnosis other than the communication by CAN, the method of changing the frequency of diagnostic data is employable.

2-1 Unit to be diagnosed 2-3 Reference unit 2-6 Reference data storage unit 2-7 Comparison operation unit 2-8 Diagnostic data storage unit 2-9 Diagnostic result storage unit 2-11 Reference data time storage unit 2-12 Diagnosis Data reception time storage unit 2-23 Signal generation unit 2-24 Reference data storage unit 2-29 First CAN bus 2-30 Second CAN bus

Claims (6)

In the diagnostic device for detecting an abnormality by performing normal communication between the diagnosis target unit and the reference unit via the first CAN bus,
The diagnostic target unit is:
A diagnostic data storage unit that reads and stores diagnostic data transmitted from the reference unit by diagnostic communication with its own clock;
A first reference data storage unit for storing predetermined reference data;
A comparison operation unit that compares the diagnostic data read from the diagnostic data storage unit with the reference data read from the first reference data storage unit;
A diagnostic result storage unit for storing a diagnostic result obtained by the comparison by the comparison calculation unit;
A diagnostic apparatus comprising: The reference unit is
A second reference data storage unit that stores the same reference data as the reference data stored in the first reference data storage unit of the diagnostic target unit;
A signal generation unit that generates diagnostic data based on reference data read from the second reference data storage unit in response to a diagnosis request from the diagnosis target unit and transmits the diagnosis data to the diagnosis target unit by diagnostic communication;
The diagnostic apparatus according to claim 1, further comprising:   3. The diagnosis apparatus according to claim 1, wherein the diagnosis target unit and the reference unit are provided separately from the first CAN bus and are connected by a second CAN bus that performs diagnosis communication. .   3. The diagnostic apparatus according to claim 2, wherein the reference data stored in the second reference data storage unit can vary a section not synchronized in accordance with an abnormal level of a clock to be detected.   5. The diagnosis apparatus according to claim 4, wherein the diagnosis target unit confirms whether or not the diagnosis data received from the reference unit matches the reference data stored in the second reference data storage unit. . The diagnostic target unit is:
A diagnostic data reception time storage section for storing diagnostic data reception time which is a time required for reception from the reference unit;
A reference data time storage unit that stores reference data time that is known data indicating time required for normal transmission and reception with the reference unit;
The comparison operation unit checks whether the diagnostic data reception time read from the diagnostic data reception time storage unit matches the reference data time read from the reference data time storage unit. The diagnostic device described.

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