DE102015208294A1 - Data recorder and data logger - Google Patents

Abstract

In a data logger, data acquisition means acquires a variety of diagnostic data contained in data generated in a vehicle. Importance level setting means set an importance level indicating the importance of an abnormal part corresponding to each part of the diagnosis data based on the kind of the diagnosis data. Anomaly level adjustment means sets, for each part of the diagnostic data, a degree of anomaly indicative of an extent of the anomaly, using models created for each part of the diagnostic data and each type of diagnostic data. Recording parameter setting means sets, for each part of the diagnostic data, a recording parameter that influences the data size when a recording section is allowed to record data based on the degree of importance and the degree of anomaly. Recording means allows the recording section to record parts of the generated data according to the recording parameter.

Description

CROSS-REFERENCE TO A RELATED APPLICATION

This application is based on and claims the benefit of the prior art priority Japanese Patent Application No. 2014-95984 filed May 7, 2014, the disclosure of which is incorporated herein by reference.

background

(Technical field)

The present invention relates to a data recording apparatus which records data generated in an own vehicle and a data recording program.

(State of the art)

There is known a data recording apparatus which, according to an error pattern (importance of the error parts), changes the sampling rate when recording data to save storage capacity in recording the data (for example, refer to FIG JP-A-2007-41952 ).

However, since this data recording apparatus sets a similar sampling rate regardless of the extent of the error, data is unnecessarily collected when the extent of the error is small, and memory space is unnecessarily consumed.

BRIEF DESCRIPTION OF THE INVENTION

One embodiment provides a data logger that records data generated in a vehicle and can optimize the capacity of the memory in data logging.

As an aspect of this embodiment, a data recorder is installed in a vehicle and allows a recording section to record data generated in the vehicle. The device includes: data transfer means which receive a plurality of diagnostic data contained in the data generated in the vehicle; Importance level setting means that sets an importance level indicating the importance of an abnormal part corresponding to each part of the diagnosis data based on at least the type of the diagnosis data; Anomaly level adjusting means that sets, for each part of the diagnostic data, an abnormality level indicative of an extent of the anomaly by using models established for each part of the diagnostic data and each type of the diagnostic data; Recording parameter setting means which sets, for each part of the diagnosis data, a recording parameter which influences the data size when the recording section is allowed to record data based on the degree of importance and the degree of anomaly and recording means which allow the recording section according to the recording parameters, at least part of the generated data record.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

1 a block diagram showing a schematic configuration of a data recording system;

2 Fig. 10 is a flowchart showing a data recording operation performed by the CPU of a data logger;

3A . 3B and 3C are illustrations for explaining a method of calculating a degree of importance;

4 Fig. 12 is a diagram for explaining an example of importance-degree map allocation according to a modification;

5A and 5B Figures are illustrations for explaining a method of calculating an anomaly degree;

6A and 6B are illustrations for explaining a method of setting parameters;

7 Fig. 13 is a diagram for explaining an example of the timing of the collection of sensor data;

8A and 8B Figures are diagrams for explaining an example of a method of setting a priority level in storing data;

9 Fig. 10 is a flowchart showing a data storage operation in the data recording operation;

10A and 10B FIG. 15 is graphs illustrating an example of a method of setting a priority level according to a modification; FIG. and

11A and 11B Figures are diagrams for explaining a method of setting parameters according to a modification.

DETAILED DESCRIPTION OF THE PREFERRED

EMBODIMENTS

Embodiments of the present invention will now be described with reference to the accompanying drawings. It is noted that in the following embodiments, like reference numerals denote substantially equal parts.

(Structure of the Embodiment)

A data logging system 1 is installed in a car (own vehicle) such as a passenger vehicle. The data logging system 1 changes the data size when recording data, considering an importance level indicating the importance of an abnormal part of the own vehicle and a degree of abnormality indicating the amount of abnormality to optimize the recording data size.

Specially, as in 1 shown closes the data logging system 1 a data recorder 10 , various ECUs (electronic control units) 21 to 24 and different sensors 25 with a. The data recorder 10 , the electronic control units 21 to 24 and the sensors 25 are with a communication line 5 connected to communicate with each other.

The ECUs 21 to 24 include an engine control unit (engine-ECU) 21 with a, which controls the engine of the own vehicle, a brake control unit 22 , which controls the brakes of the own vehicle, a steering control unit 23 which controls a steering angle of the own vehicle, and a suspension control device 24 which controls the vehicle height of the own vehicle and the position of the own vehicle. The sensors 25 include a vehicle speed sensor that measures the speed of the own vehicle, an acceleration sensor that measures the acceleration of the own vehicle, and a yaw rate sensor that measures the angular velocity of the own vehicle.

The controllers 21 to 24 give calculation results thereof and values received from the sensors connected thereto on the communication line 5 , The sensors 25 give detected signals (sensing signals) on the communication line 5 out.

The data recorder 10 is configured as a computer that has a CPU 11 contains and a memory 12 , such as ROM or RAM. The CPU 11 performs various operations, which will be described later, based on a program (data recording program) stored in memory 12 is stored. While performing such processes, the data logger allows 10 the memory 12 the recording and caching of a portion of the data received over the communication link. It is noted that the data recorder 10 all at times received data in memory 12 contains (at least during the maximum value of | TS |, which is the absolute value of the memory start time TS, which will be described later).

(Process of the Embodiment)

In the data recording unit 1 , which is configured as described above, performs the CPU 11 in the data recorder 10 a data recording operation that is in 2 is shown. The data logging process allows the memory 12 Record data taking into account the degree of importance and the degree of anomaly of the received data. In addition, the data recording operation starts when power is supplied to the vehicle. Thereafter, the data recording operation is repeatedly performed with a constant period.

In the data recording process, as in 2 shown first in step S110, the CPU obtains 11 Data temporarily in the memory 12 are recorded. The data shows the output values of the control units 21 to 24 and the sensors 25 ,

Next, in step S120, the CPU resets 11 a variable k on 1. The variable k is a value for designating the kind of anomaly (the kind of abnormal condition) that is recognized and increases to the prepared number K, which is the number of types of abnormality conditions, in the later Process.

Next in step S130, the CPU performs 11 an importance level calculation process. It is noted that steps S130 through S165 are performed for each piece of data previously set as abnormality detection diagnosis data, and the diagnosis data in the temporarily recorded data in the memory 12 are included.

The degree of importance indicates the importance of an anomalous part. The abnormal part is classified by an ID for identifying the kind of the data. The ID is included in the diagnostic data.

In the importance level calculation process, as in 3A shown, the CPU gets 11 First, in step S210, the own vehicle speed v from the vehicle speed sensor of the sensors 25 ,

Next, in step S220, the CPU calculates 11 the degree of importance y _k . As in 3B As shown, such as the degree of importance y _k , the functions G _{k are set} according to the type of the kind of anomaly conditions. As an example, as in 3C shown, each of the functions G _{k is} a function of its own vehicle speed v.

Especially for the diagnostic data of the base functional systems, including a powertrain system, a steering system, a brake system, and the like, which may affect the safety of the traveling vehicle, the degree of importance is set to a relatively high value regardless of the vehicle speed. As the vehicle speed increases, the degree of importance increases.

In addition, for the diagnostic data of a body system including a door lock system, a power window system, an air conditioning system, and the like, which do not affect the vehicle driving safety but are relatively important, the importance level is set lower than that of the diagnosis data of the base function system and higher than that of the diagnosis data of an entertainment system , which will be described later. Further, for the diagnosis data of the entertainment system including an audio system, an internal vehicle lighting system and the like which does not affect the vehicle driving safety but only affects the convenience for the passengers, the importance level is set lower than that of the diagnosis data of the body system.

It should be noted that, as in 3C For example, for the diagnostic data of the entertainment system, the degree of importance may be set as if it were constant regardless of the vehicle speed v. In addition, as in 4 the degree of importance may be a fixed value according to the nature of the anomaly condition.

Upon completion of the above steps, the importance level calculation process ends and the data recording operation returns 2 back. Then, in step S140, the CPU performs 11 anomaly-degree calculation process for calculating the anomaly. The degree of anomaly indicates the extent of the abnormality of the diagnostic data.

In the anomaly level calculation process, as in 5A shown, the CPU calculates 11 an abnormality degree using a model based on the distribution of the diagnosis data previously collected under normal conditions and the received diagnosis data. In this case, for example, a classifying support vector machine (SVM) may be used.

In particular, the following expression is determined using Mahalanobis' generalized distance between the means of distributing the normal diagnostic data and the observed diagnostic data or a normal average function f (t) and an observed average function g (t). The normal average function f (t) is an average function of the normal diagnostic data. The observed average function g (t) is an average function of a large number of parts of the diagnostic data.

Here, the distance d between the distribution of the normal diagnostic data and those of the observed diagnostic data is calculated.

After the distance d is calculated, the input of the distance d to a predetermined function achieves an anomaly degree s of the function. For example, as in 5B As shown, the function may be a linear shape or a square shape at a distance d. If the distance d is not more than a normal limit, the degree of anomaly s = 0. The time sequence information may be taken into consideration. For example, the weight of new data can be increased.

Next, in S150, the CPU determines 11 Data storage information. In this process, the CPU puts 11 Parameters that can influence the data size, such as the type of data (type of sensor data), memory start time (TS _{k, m} ), memory stop time (TE _{k, m} ), and a sampling period (SP _{k, m} ), using the degree of importance y _k and the degree of anomaly s.

For example, as in function 6A is shown, the type of sensor data (SD _m ) to be stored depending on the type of abnormality condition (FD _k ) is set. Based on the type of anomaly conditions and the type of sensor data, the CPU selects 11 a function (F _{k, m} ) for setting the memory start time, the memory stop time, and the sampling period. An example of the function F _{k, m} is shown in the following expression: F _{k, m} (s): = [TS _{k, m} (s), TE _{k, m} (s), SP _{k, m} (s)]

As in 6B 1, the memory start time and the memory stop time are set so that the data collection time period becomes longer as the degree of anomaly s becomes higher. It should be noted that the time 0 in the graph indicates a time at which the trigger for storing data (the degree of abnormality s ≠ 0) is generated.

In addition, memory start time and memory stop time also depend on the degree of importance y _k . As the importance level y _{k of} the diagnostic data becomes higher, the data collection time period is lengthened. For example, the memory start time and the memory stop time, which are set depending on the degree of anomaly s, may be modified depending on the importance level y _k .

Additionally shows 6B in that data is not collected when the degree of anomaly is 0. The graph in 6B is an example of the function F _{k, m} . Each function F _{k, m} can be different.

In addition, the sampling period may be set, for example, as being inversely proportional to the degree of anomaly s. That is, as the degree of anomaly s and the degree of importance y _{k become} higher, the sampling period can be set smaller.

Below the setting described above are as in 7 2, the data collection time and the sampling period are individually set depending on the type of the sensor data being stored.

Next, in step S155, the CPU determines 11 Whether there is a recording timing or not If there is no recording timing (S155: NO), the process goes to the later-described step S165 continues. If the recording timing is present (S155: YES), the CPU performs 11 a data storage operation (S160).

In the data storage process, as in 8A shown, the CPU continues 11 a priority level, depending on the importance level y _k and the degree of abnormality s of the diagnostic data, and overwrites data having a lower priority level when the capacity of the memory 12 is not enough. For example, as in 8B shown, the CPU saves 11 Data that has a higher priority level, at the low-numbered address in memory 12 , If the memory 12 filled, clears the CPU 11 the data that has a low priority level.

The data storage process is explained in detail. As in 9 shown in step S310, the CPU receives 11 Data storage information. In this step, the CPU gets 11 Information about importance level, degree of anomaly, memory start time, and memory stop time.

Next, in step S320, the CPU inserts 11 Add the datastore information to the database. In step S330, the CPU calculates 11 the total data size (DBS) including the data in memory 12 , Next, in step S340, the CPU compares 11 the capacity of the memory 12 (DB _max ) with the total data size.

When the capacity of the memory 12 is equal to or greater than the total data size (S340: NO), the data storage operation is completed. When the capacity of the memory 12 is smaller than the total data size (S340: YES), in steps S350 to S370, the CPU sorts 11 the stored data based on level of importance, degree of anomaly, and memory start time. That is, the CPU 11 sorts the stored data by priority level as described above. For the plurality of data parts having the same priority level, a higher priority level is applied to the more recent data.

Next, in step S380, the CPU writes 11 the data in the order of priority in memory 12 and completes the data storage process. Upon completion of the data storage process, then returning to 2 In step S165, the CPU determines whether the obtained data has been stored or not (that is, whether or not the memory stop time has elapsed).

If the data has not been stored (S165: NO), the process returns to step S155. If the data has been stored (S165: YES) in step S170, the CPU compares 11 the variable k with the number K, which is the number of kinds of abnormal conditions. If the variable k is smaller than the number K (S170: NO), the CPU increases 11 the variable k, and the process returns to step S130.

If the variable k is equal to (or greater than) the number K (S170: YES), the CPU ends 11 the data recording process.

(Advantages of the embodiment)

The data recorder 10 (CPU 11 ) obtains many kinds of diagnostic data contained in the own vehicle generated data (S110), and sets an importance degree indicating the importance of an abnormal part corresponding to each part of the diagnostic data based on at least the kind of the diagnostic data (S130) , In addition, the data recorder represents 10 for each part of the diagnostic data, an abnormality degree indicating the extent of the abnormality by using the received diagnosis data and models prepared for each kind of the normal diagnosis data (S140).

The data recorder 10 For each part of the diagnostic data, sets a recording parameter that affects the data size when a recording section is allowed to record data based on the degree of importance and the degree of abnormality (S150). In addition, the data recorder allows 10 the recording section to record at least a part of the generated data according to the recording parameters (S155, S160).

As the data recorder 10 the recording parameters which influence the data size, taking into account a degree of importance which sets the importance of an abnormal part and an abnormality degree indicating an extent of the anomaly, the recording data size can be optimized.

In addition, the data recorder represents 10 the degree of anomaly using a model based on a distribution of the diagnostic data previously collected under normal conditions.

As the data recorder 10 the distribution used in the calculation of the degree of abnormality, the degree of abnormality can be suitably calculated according to the distribution of the diagnosis data which has been collected under normal condition. In addition, the anomaly level calculation can be simplified.

In addition, provides the data recorder 10 the degree of anomaly using a degree of divergence calculated by the model and the received diagnostic data.

As the data recorder 10 Adjust the degree of anomaly by using the degree of divergence, the process of adjusting the degree of anomaly can be simplified.

Additionally, if the degree of divergence is less than a predetermined lower limit, the data logger continues 10 the degree of anomaly to zero.

As the data recorder 10 ignoring the degree of divergence less than the lower limit, the calculation can be simplified. In addition, the data size can be reduced.

In addition, provides the data recorder 10 at least one of the types of data, the data size, a sampling rate, and a detection time range as a recording parameter.

The data recorder 10 can reliably change the data size to be recorded according to the degree of importance and the degree of anomaly.

In addition, the data recorder determines 10 the presence or absence of a recording area in the recording section. If no recording area exists, the data recorder selects 10 the data whose degree of importance is lower than a predetermined limit value out of the recorded data in the recording section as a destination to be overwritten. Then the data recorder overwrites 10 the data selected as the destination to be overwritten with the data to be recorded according to the recording parameters.

According to the data recorder 10 can prevent important data from being overwritten if there is no recording area.

In addition, the data recorder represents 10 the abnormality degree that is obtained when the abnormality affects the vehicle operational safety is higher in the priority degree than the degree of abnormality obtained when the abnormality does not affect the vehicle operational safety.

According to the data recorder 10 For example, larger data may be recorded when the vehicle is in a situation where the vehicle is difficult to operate.

In addition, the data recorder represents 10 the importance level higher as the speed of the own vehicle increases.

That is, since the own vehicle's risk increases as the own vehicle speed increases, the importance level is set higher. According to the data recorder 10 the degree of importance can be suitably adjusted.

Other Embodiments

It should be understood that the present application is not limited to the arrangement as described above, but any and all modifications, variations or equivalents which may occur to a person familiar with the art should be understood. are considered to fall within the scope of the present invention.

In the above embodiment, the degree of importance is defined as a function of the vehicle speed v. Anyway, like in 10A shown, the degree of importance can be a constant depending on the anomaly condition (FD _k ). In addition, in the above embodiment, the degree of priority becomes higher as the degree of importance becomes higher. However, as in 10B The degree of priority may be adjusted based on an appropriate balance between the degree of importance and the degree of anomaly. It should be noted that diagnostic data related to the base function systems are preferably recorded.

In addition, in the above embodiment, the memory start time (TS _{k, m} ) and the memory stop time (TE _{k, m} ) are variably set depending on the degree of abnormality s. However, as in 11A shown, these timings be set as constant. In addition, the sampling rate f can be set using a function in which the sampling rate increases (that is, the sampling period becomes smaller) as the degree of anomaly s increases.

In the above embodiment, older data is preferably overwritten. However, an overwritten area may be determined depending on the types of the anomaly conditions. In particular, a function H _{k, m may be} provided which outputs an importance level y _k based on the inputted anomaly degree S and the data acquisition time t. y _k = H _{k, m} (s, t), TS _{k, m} (s) ^{≦ ∀} t ^≦ TE _{k, m} (s)

In the above expression, y _k indicates the degree of importance, s indicates the degree of anomaly, and t indicates the data acquisition time.

Therefore, an importance level in the database (memory 12 ) in the direction of the time axis, and the diagnostic data having a low degree of importance can preferably be overwritten. Accordingly, important data having a higher priority level can be reliably stored in a finite capacity. In addition, the diagnostic data having a relatively low priority level can also be effectively stored.

(Relationship between Embodiment and Means of Invention)

The data recorder 10 in the above embodiment corresponds to a data recording device. In the above embodiment, step S110 corresponds to the data recording device 10 carried out, data transfer means (section).

The step S130 corresponds to importance level setting means (section). The step S140 corresponds to abnormality degree setting means (section). The step S150 corresponds to recording parameter setting means (section). Steps S155 and S160 correspond to recording means (section).

The step S340 corresponds to recording area determining means (section).

Steps S350 to S380 correspond to selection means for a destination (section) to be overwritten.

Hereinafter, aspects of the above-described embodiment will be summarized.

As an aspect of the embodiment, a data logger becomes 10 provided. Data transfer means (S110) obtains a plurality of kinds of diagnosis data included in the data generated in the vehicle. Importance level setting means (S130) sets an importance level indicating the importance of an abnormal part corresponding to each part of the diagnosis data based on at least the kind of the diagnosis data. Anomaly Wheel Adjustment means (S140) sets an abnormality degree for each part of the diagnostic data indicating an extent of the abnormality by using models created for each part of the diagnostic data and each type of the diagnostic data.

In addition, recording parameter setting means (S150) sets, for each part of the diagnostic data, a recording parameter that affects the data size when the recording section is allowed to record data based on the degree of importance and the degree of anomaly. Recording means (S155, S160) allow the recording section to record at least part of the generated data according to the recording parameters.

Since, according to the data recorder, the recording parameters affecting the data size are observed considering a degree of importance indicating the importance of an abnormal part, and an abnormality degree indicative of the degree of anomaly, the memory capacity in recording the data can be optimized.

It is noted that a data recording program may be provided which allows a computer to operate as any of the means of the data logger.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• JP 2014-95984 [0001]
• JP 2007-41952 A [0003]

Claims (9)

Data recorder ( 10 ) installed in a vehicle and a recording section ( 12 ) allows to record data generated in the vehicle, comprising: data transferring means (S110) for accepting a plurality of diagnosis data included in the data generated in the vehicle; Importance level setting means (S130) that sets an importance level indicating the importance of an abnormal part corresponding to each part of the diagnosis data based on at least the type of the diagnosis data; Abnormality degree setting means (S140) for each part of the diagnostic data setting a degree of abnormality indicating an abnormality amount using models created for each part of the diagnosis data and each kind of diagnosis data; Recording parameter setting means (S150) for each part of the diagnosis data, setting a recording parameter that influences the data size when allowing a recording section to record data based on the degree of importance and the degree of anomaly, and recording means (S155, S160) representing a recording section allow to record at least part of the generated data according to the recording parameter. A data recording apparatus according to claim 1, wherein the abnormality degree setting means sets the degree of anomaly by using a model based on the distribution of the diagnosis data which is collected under normal conditions. A data recording apparatus according to claim 1, wherein the abnormality degree setting means sets the degree of anomaly by using a degree of divergence calculated from the model and the diagnosis data. A data recording apparatus according to claim 3, wherein the abnormality degree setting means sets the degree of abnormality to 0 when the degree of divergence is smaller than a predetermined lower limit. A data recording apparatus according to claim 1, wherein the recording parameter setting means sets at least one type of data, the data size, a sampling rate and / or a detection time range. The data logger of claim 1, further comprising: Recording area determining means (S340) for determining the presence or absence of an area for recording in the recording section; and Target overwriting targeting means (S350 to S380) which selects data as a target to be overwritten whose degree of importance is less than a predetermined threshold value from the recorded data in the recording section if there is no recording area; the recording means overwrite the data selected as the destination to be overwritten in accordance with the recording parameters with the data to be recorded. A data recording apparatus according to claim 1, wherein the importance level setting means sets the degree of importance in an abnormal condition in which the vehicle is hard to operate higher than the degree of importance in an abnormal condition in which the vehicle operational safety is not impaired. A data recording apparatus according to claim 1, wherein the importance level setting means sets the degree of importance higher as the vehicle speed increases. A data recording program which allows a computer to operate as any of the means of the data recording apparatus of claim 1.

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