JP6252344B2 - Data recording apparatus and data recording program - Google Patents

Description

  The present invention relates to a data recording apparatus and a data recording program for recording data generated in a host vehicle.

  As the above data recording device, there is known a device that changes a sampling rate when data is recorded in accordance with a failure pattern (importance of a failure part) in order to save a recording capacity for recording data (for example, , See Patent Document 1).

JP 2007-41952 A

  However, in the above data recording apparatus, since the same sampling rate is set regardless of the degree of failure, unnecessary data is collected when the degree of failure is light, and the recording capacity is wasted. There was a point.

  Accordingly, in view of such problems, it is an object of the present invention to optimize a recording capacity when recording data in a data recording apparatus that records data generated in the host vehicle.

  In the data recording apparatus of the present invention, the data acquisition unit acquires a plurality of types of abnormality detection data among the generated data generated in the host vehicle, and the importance level setting unit includes at least an abnormality for each abnormality detection data. Based on the type of detection data, an importance level representing the importance of the abnormal part corresponding to the data is set. Further, the abnormality level setting means sets an abnormality level representing the degree of abnormality by using abnormality detection data and a model prepared in advance for each type of abnormality detection data for each abnormality detection data.

  Then, the recording parameter setting means sets a recording parameter, which is a parameter that affects the amount of data when the data is recorded in the recording unit, for each abnormality detection data, based on the importance level and the abnormality level. Causes the recording unit to record data in at least part of the generated data according to the recording parameters.

  According to such a data recording apparatus, since the recording parameter, which is a parameter that affects the data amount, is set in consideration of the importance indicating the importance of the abnormal part and the abnormality indicating the degree of abnormality, the data is recorded. The recording capacity can be optimized.

  In order to achieve the above object, the computer may be a data recording program for realizing each unit constituting the data recording apparatus. Further, the descriptions in the claims can be arbitrarily combined as much as possible. At this time, a part of the configuration may be excluded within a range in which the object of the invention can be achieved.

1 is a block diagram showing a schematic configuration of a data recording system 1 to which the present invention is applied. 3 is a flowchart showing a data recording process executed by a CPU 11 of the data recording apparatus 10. It is explanatory drawing which shows the calculation method of importance. It is explanatory drawing which shows an example of the importance map of a modification. It is explanatory drawing which shows the calculation method of an abnormality degree. It is explanatory drawing which shows the setting method of the parameter which affects data amount. It is explanatory drawing which shows an example of the collection timing of sensor data. It is explanatory drawing which shows an example of the setting method of the priority at the time of preserve | saving data. It is a flowchart which shows the data preservation | save process among data recording processes. In a modification, it is a graph which shows an example of the priority setting method. In a modification, it is explanatory drawing which shows the parameter setting method.

Embodiments according to the present invention will be described below with reference to the drawings.
[Configuration of this embodiment]
The data recording system 1 to which the present invention is applied is mounted on a vehicle (own vehicle) such as a passenger car, for example. Then, the data recording system 1 takes into account the importance of the importance of the abnormal part of the host vehicle and the degree of abnormality indicating the degree of abnormality, and changes the amount of data when recording the data. The recording capacity for recording can be optimized.

  Specifically, as shown in FIG. 1, the data recording system 1 includes a data recording device 10, various ECUs (electronic control devices) 21 to 24, and various sensors 25. The data recording device 10, the various ECUs 21 to 24, and the various sensors 25 are each connected to the communication line 5, and are configured to be able to communicate with each other.

  The various ECUs 21 to 24 include an engine ECU 21 that controls the engine of the host vehicle, a brake ECU 22 that controls the brake of the vehicle, a steering ECU 23 that controls the steering angle of the host vehicle, and the height of the host vehicle and the tilt of the host vehicle. The suspension ECU 24 and the like are provided. The various sensors 25 include a vehicle speed sensor that detects the traveling speed of the host vehicle, an acceleration sensor that detects acceleration applied to the host vehicle, a yaw rate sensor that detects the rotational angular velocity of the host vehicle, and the like.

  These ECUs 21 to 24 output the calculation results by themselves and the values from the sensors connected thereto to the communication line 5. Various sensors 25 output values detected by themselves to the communication line 5.

  The data recording device 10 is configured as a computer including a CPU 11 and a memory 12 such as a ROM and a RAM. The CPU 11 executes various processes to be described later based on the program recorded in the memory 12. The data recording device 10 records part of the data received via the communication line 5 in the memory 12 and holds it while executing such processing. The data recording apparatus 10 temporarily holds all received data in the memory 12 (at least as much as the absolute value | TS | of the storage start timing TS described later).

[Process of this embodiment]
In the data recording system 1 configured as described above, the CPU 11 of the data recording apparatus 10 performs the data recording process shown in FIG. The data recording process is a process of recording data in the memory 12 while taking into account the importance and abnormality of the received data. Further, the data recording process is a process that is started when the vehicle is turned on, for example, and thereafter repeatedly performed at regular intervals.

  In the data recording process, as shown in FIG. 2, first, data temporarily recorded in the memory 12 is input (S110). The data here indicates outputs from the ECUs 21 to 24 and the sensor 25.

  Subsequently, the variable k is set to 1 (S120). The variable k is a value for designating the type of abnormality to be detected (type of abnormality detection), and increases to the number K of types of abnormality detection prepared in advance in subsequent processing.

  Subsequently, importance calculation processing is performed (S130). Note that the processing of S130 to S165 is performed for each data set in advance as determination data for performing abnormality determination among the data temporarily recorded in the memory 12.

Here, the importance represents the importance of the abnormal part. Which part is the abnormal part is recognized by the ID for specifying the data type included in the determination data.
In the importance calculation process, as shown in FIG. 3A, first, the host vehicle speed v is acquired (S210). The own vehicle speed v is acquired from a vehicle speed sensor among the various sensors 25.

Subsequently, the importance y _k is calculated (S220). Here, importance y _k, as shown in FIG. 3 (b), are set function G _k of importance is set according to the type of abnormality detected, each of the function G _k, for example, FIG. As shown in FIG. 3 (c), it is a function corresponding to the vehicle speed v.

  In particular, the judgment data of the driving safety system (running safety system) related to power, steering, etc., which can affect the driving of the vehicle, is set to a relatively high importance regardless of the vehicle speed, and the vehicle speed increases. Then the importance becomes even higher.

  In addition, body judgment data related to door locks, power windows, air conditioners, etc., which are relatively important but have no effect on the driving of the vehicle, are less important than the judgment data for the driving safety system. It is set so as to be higher than entertainment-related determination data described later. Furthermore, entertainment-related determination data relating to audio, interior lighting, etc., which has no effect on vehicle travel and affects only passenger comfort, is set to be less important than body-based determination data.

  As shown in FIG. 3 (c), for example, the determination data for the entertainment system may be set so that the importance is constant regardless of the vehicle speed v. Also, as shown in FIG. 4, the importance may be a fixed value depending on the type of abnormality detection.

  When such processing ends, the importance calculation processing ends, and the flow returns to FIG. Then, an abnormality degree calculation process is performed (S140). Here, the degree of abnormality represents the degree of abnormality of the determination data.

  In the degree of abnormality calculation process, as shown in FIG. 5A, the degree of abnormality is obtained by using a model generated based on the distribution of normal data collected in advance and the input determination data. Ask. At this time, for example, a one-class SVM (support vector machine) may be used.

  Specifically, the Mahalanobis distance between the centroid position of the distribution of normal data and the determination data, or the observed centroid function that is a centroid function of the normal centroid function f (t) that is a centroid function of normal data and a plurality of determination data Using g (t),

とし、正常データの分布と判定用データとの距離ｄを求めればよい。

And the distance d between the distribution of normal data and the determination data may be obtained.

  When the distance d is obtained, the degree of abnormality s is obtained by applying the distance d to a preset function. For example, as shown in FIG. 5B, the degree of abnormality s may be a linear function or a quadratic function of the distance d. If the distance d is up to the normal distance threshold, the degree of abnormality s is set to zero. May be. At this time, a time series may be taken into consideration, such as increasing the weight of new data.

Subsequently, the data storage information is determined (S150). In this process, the type of data to be stored (the type of sensor data) using the importance y _k and the degree of abnormality s, the data storage start timing (TS _{k, m} ), the storage end timing (TE _{k, m} ), Alternatively, parameters that can affect the data amount such as the sampling period (SP _{k, m} ) are set.

For example, as shown in FIG. 6A, the type (SD _M ) of sensor data to be stored is set according to the type of failure determination (FD _K ), and based on these, data storage start timing is set. A function for setting (TS _{k, m} ), storage end timing (TE _{k, m} ), and sampling period (SP _{k, m} ) is selected. An example of the selected function is shown in the following equation.

ここで、データの保存開始タイミング（ＴＳ_k,m）やデータの保存終了タイミング（ＴＥ_k,m）は、図６（ｂ）に示すように、異常度ｓが高くなるにつれて、データ収集時間が長くなるよう設定される。なお、グラフ中の時刻０は、データを保存する旨のトリガ（異常度ｓが０でないこと）が発生した時刻を示す。

Here, the data storage start timing (TS _{k, m} ) and the data storage end timing (TE _{k, m} ), as shown in FIG. Set to be longer. Note that time 0 in the graph indicates the time at which a trigger to save data (abnormality s is not 0) occurs.

Also, storage end timing of the storage start timing and data of the data will also depend on the severity y _k, the data acquisition time as severity y _k increases the determination data is set to be longer. For example, the data storage start timing and the data storage end timing set according to the degree of abnormality s may be corrected according to the importance y _k .

In the example shown in FIG. 6B, when the degree of abnormality is 0, it indicates that data collection is not performed. The graph shown in FIG. 6B is an example of a map in a certain function F _{k, s} (s), and different maps may be prepared depending on the selected function.

The sampling period (SP _{k, m} ) may be set to be inversely proportional to the degree of abnormality s, for example. That is, the sampling period is set shorter as the degree of abnormality s and the degree of importance y _k become higher.

If set in this way, as shown in FIG. 7, the timing and sampling cycle for collecting data are individually set according to the type of sensor data (SD) to be stored.
Subsequently, it is determined whether or not it is time to save data (S155). If it is not time to save data (S155: NO), the process proceeds to S165 described later. If it is the timing to save the data (S155: YES), the data saving process is performed (S160).

In the data storage process, as shown in FIG. 8A, priority is set according to the importance y _k and the abnormality s of the determination data, and when the recording capacity of the memory 12 (DB) is insufficient. Overwrite the one with low priority. For example, as shown in FIG. 8B, when data is recorded in the memory 12, the higher the priority, the smaller the number is recorded, and the lower priority is deleted when the memory 12 overflows. .

  For details of the data storage process, as shown in FIG. 9, first, data information is acquired (S310). In this processing, in this processing, information on the importance level and abnormality level of the determination data, data storage start timing (acquisition start time), and data storage end timing (acquisition end time) is acquired.

  Subsequently, the data information is recognized as data to be recorded (S320), and the total data DBS in the memory 12 including this data is calculated (S330). Subsequently, the capacity DBmax of the memory 12 and the total data amount DBS are compared (S340).

  If the capacity DBmax of the memory 12 is equal to or greater than the total data amount DBS (S340: NO), the data storage process is terminated. If the capacity DBmax of the memory 12 is less than the total data amount DBS (S340: YES), the data relating to the importance level is rearranged, the data relating to the degree of abnormality is rearranged, and the data relating to the acquisition start time is rearranged (S350 to S370). To implement. That is, rearrangement is performed according to the above-described priorities, and new ones having higher priorities are given higher priorities.

  Subsequently, writing to the memory 12 is performed in descending order of priority (S380), and the data storage process is terminated. When such processing is completed, the process returns to FIG. 2 to determine whether or not the acquired data has been stored (that is, whether or not the data storage end timing has elapsed) (S165).

  If the data storage has not been completed (S165: NO), the process returns to S155. If the data storage is completed (S165: YES), the variable k is compared with the number K of types of abnormality detection (S170). If the variable k is less than the number K of types of abnormality detection (S170: NO), the variable k is incremented and the process returns to S130.

If the variable k matches the number K of types of abnormality detection (or more than that) (S170: YES), the data recording process is terminated.
[Effects of this embodiment]
In the data recording apparatus 10 (CPU 11) described in detail above, a plurality of types of abnormality detection data among the generated data generated in the host vehicle is acquired (S110), and at least for each abnormality detection data, Based on the type of abnormality detection data, an importance level representing the importance of the abnormal part corresponding to the data is set (S130). In addition, the data recording device 10 sets an abnormality level representing the degree of abnormality by using abnormality detection data and a model prepared in advance for each type of abnormality detection data for each abnormality detection data (S140). .

  Then, the data recording device 10 sets a recording parameter, which is a parameter that affects the amount of data when the recording unit records data, for each abnormality detection data based on the importance level and the abnormality level (S150). According to the recording parameters, at least a part of the generated data is recorded in the recording unit (S155, S160).

  According to such a data recording apparatus 10, since the recording parameter that is a parameter that affects the data amount is set in consideration of the importance indicating the importance of the abnormal part and the abnormality indicating the degree of abnormality, the data is stored. The recording capacity at the time of recording can be optimized.

In the data recording apparatus 10 described above, the degree of abnormality is set using a model set based on the distribution when the abnormality detection data is normal.
According to such a data recording apparatus 10, since the distribution is used when obtaining the degree of abnormality, the degree of abnormality can be appropriately obtained according to the distribution when the abnormality detection data is normal. In addition, the calculation of the degree of abnormality can be simplified.

In the data recording apparatus 10 described above, the degree of abnormality is set using the degree of divergence calculated from the model and abnormality detection data.
According to such a data recording apparatus 10, since the degree of abnormality is set using the degree of divergence, the processing when setting the degree of abnormality can be simplified.

In the data recording apparatus 10 described above, the degree of abnormality is set to 0 when the degree of divergence is less than a preset lower limit value.
According to such a data recording device 10, since the divergence degree when the divergence degree is less than the lower limit value is ignored, the calculation at this time can be simplified. In addition, the amount of stored data can be reduced.

In the data recording apparatus 10 described above, at least one of data type, data amount, sampling rate, and data acquisition range is set as a recording parameter.
According to such a data recording device 10, the data amount of data to be recorded can be reliably changed according to the importance level and the abnormality level.

  Further, in the data recording apparatus 10 described above, the presence / absence of a recordable area in the recording unit is determined. If there is no recordable area, the importance of the data recorded in the recording unit is higher than a preset threshold value. Select low data for overwriting. Then, according to the recording parameter, the data to be recorded is overwritten and recorded on the data selected as the overwriting target.

According to such a data recording apparatus 10, it is possible to make it difficult for important data to be overwritten when there is no recordable area.
Further, in the data recording apparatus 10 described above, an abnormality that makes it difficult for the vehicle to travel is set higher than an abnormality that is not related to the traveling of the vehicle.

According to such a data recording device 10, it is possible to record more data about an abnormality that makes it difficult for the vehicle to travel.
In the data recording apparatus 10 described above, the importance is set higher as the traveling speed of the host vehicle increases.

  That is, since the danger to the host vehicle increases as the traveling speed of the host vehicle increases, the importance is set high. According to such a data recording apparatus 10, it is possible to appropriately set the importance level.

[Other Embodiments]
The present invention is not construed as being limited by the above embodiment. Moreover, the aspect which abbreviate | omitted a part of structure of said embodiment as long as the subject could be solved is also embodiment of this invention. An aspect configured by appropriately combining the above-described plurality of embodiments is also an embodiment of the present invention. Moreover, all the aspects which can be considered in the limit which does not deviate from the essence of the invention specified only by the wording described in the claims are embodiments of the present invention. Further, the reference numerals used in the description of the above embodiments are also used in the claims as appropriate, but they are used for the purpose of facilitating the understanding of the invention according to each claim, and the invention according to each claim. It is not intended to limit the technical scope of

  For example, in the above embodiment, the importance is defined as a function of speed, but as shown in FIG. 10A, it may be a constant corresponding to the type of abnormality detection. Further, in the above embodiment, the priority is set high for the high importance, but as shown in FIG. 10B, the priority may be set by a comprehensive balance between the importance and the abnormality. Good. However, it is better to preferentially record only the driving data.

  In the above embodiment, the storage start timing TS and the storage end timing TE are variably set according to the degree of abnormality s. However, as shown in FIG. Good. The sampling rate f may be set using a function that increases the sampling rate (that is, shortens the sampling period) as the degree of abnormality s increases.

  In the above embodiment, the old data is set to be overwritten preferentially, but the overwriting area may be determined according to the type of abnormality detection. Specifically, a function H that outputs an importance level y with respect to the abnormality level s and the data acquisition time t is prepared in advance.

これによりデータベース（メモリ１２）内での重要度が時間方向で求まり、重要度の低いところから上書きすることができる。このようにすれば、有限容量において優先度の高い重要データを確実に保存することができる。また、比較的優先度の低いデータも効率的に保存することができる。

As a result, the importance in the database (memory 12) can be obtained in the time direction, and can be overwritten from a place with a low importance. In this way, important data with high priority in a finite capacity can be reliably stored. In addition, relatively low priority data can be efficiently stored.

[Correspondence between Configuration of Embodiment and Means of Present Invention]
The data recording apparatus 10 in the above embodiment corresponds to the data recording apparatus referred to in the present invention. In the embodiment, the process of S110 among the processes executed by the data recording apparatus 10 corresponds to the data acquisition means referred to in the present invention.

  Further, the process of S130 in the above embodiment corresponds to the importance setting means in the present invention, and the process of S140 in the above embodiment corresponds to the abnormality degree setting means in the present invention. Further, the process of S150 in the above embodiment corresponds to the recording parameter setting means referred to in the present invention, and the processes of S155 and S160 in the above embodiment correspond to the recording execution means referred to in the present invention.

  Further, the process of S340 in the above embodiment corresponds to the recordable area determining means in the present invention, and the processes in S350 to S380 in the above embodiment correspond to the overwrite target selecting means in the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Data recording system, 5 ... Communication line, 10 ... Data recording device, 11 ... CPU, 12 ... Memory, 21 ... Engine ECU, 22 ... Brake ECU, 23 ... Steering ECU, 24 ... Suspension ECU, 25 ... Various sensors.

Claims (11)

A data recording device (10) that is mounted on the host vehicle and causes the recording unit (12) to record data generated in the host vehicle.
Data acquisition means (S110) for acquiring a plurality of types of abnormality detection data among the generated data generated in the host vehicle;
Importance setting means (S130) for setting importance indicating the importance of the abnormal part to which the data corresponds, based on at least the type of the data for abnormality detection, for each abnormality detection data;
For each abnormality detection data, an abnormality degree setting means for setting an abnormality degree representing the degree of abnormality by using the abnormality detection data and a model prepared in advance for each type of abnormality detection data (S140). When,
For each of the abnormality detection data , a recording parameter that is a parameter that affects the amount of data when the recording unit records the abnormality detection data based on the importance level and the abnormality level of the abnormality detection data. Recording parameter setting means for setting (S150);
Recording execution means (S155, S160) for recording data in the recording unit at least a part of the generated data according to the recording parameters;
Equipped with a,
The recording parameter setting means includes, for each abnormality detection data, the amount of abnormality detection data to be recorded, the sampling rate, and the acquisition range when recording the abnormality detection data in the recording unit as the recording parameter. Set at least one of the
The recording parameter setting means sets the recording parameter for each abnormality detection data so that the amount of data changes according to the degree of abnormality of the abnormality detection data.
A data recording apparatus. The data recording apparatus according to claim 1, wherein
The data recording apparatus, wherein the abnormality level setting means sets the abnormality level using a model set based on a distribution when the abnormality detection data is normal. In the data recording device according to claim 1 or 2,
The data recording device, wherein the abnormality degree setting means sets the abnormality degree using a deviation degree calculated from the model and the abnormality detection data. The data recording apparatus according to claim 3, wherein
The data recording device according to claim 1, wherein the abnormality degree setting means sets the abnormality degree to 0 when the divergence degree is less than a preset lower limit value.   A data recording device (10) that is mounted on the host vehicle and causes the recording unit (12) to record data generated in the host vehicle.
  Data acquisition means (S110) for acquiring a plurality of types of abnormality detection data among the generated data generated in the host vehicle;
  Importance setting means (S130) for setting importance indicating the importance of the abnormal part to which the data corresponds, based on at least the type of the data for abnormality detection, for each abnormality detection data;
  For each abnormality detection data, an abnormality degree setting means for setting an abnormality degree representing the degree of abnormality by using the abnormality detection data and a model prepared in advance for each type of abnormality detection data (S140). When,
  Recording parameter setting means (S150) for setting a recording parameter, which is a parameter affecting the amount of data when the recording unit records data for each abnormality detection data, based on the importance and the abnormality ,
  Recording execution means (S155, S160) for recording data in the recording unit at least a part of the generated data according to the recording parameters;
  With
  The abnormality degree setting means sets the abnormality degree using a divergence degree calculated from a model set based on a distribution when the abnormality detection data is normal and the abnormality detection data,
  The degree of divergence is a distance between the center of gravity position of the distribution when the abnormality detection data is normal and the abnormality detection data.
  A data recording apparatus.   The data recording apparatus according to claim 5, wherein
  The abnormality degree setting means sets the abnormality degree to 0 when the deviation degree is less than a preset lower limit value.
  A data recording apparatus characterized by the above.   In the data recording device according to claim 5 or 6,
  The recording parameter setting means sets at least one of a data amount, a sampling rate, and a data acquisition range as the recording parameter.
  A data recording apparatus characterized by the above. In the data recording device according to any one of claims 1 to 7 ,
Recordable area determination means (S340) for determining the presence or absence of a recordable area in the recording unit;
When there is no recordable area, overwrite target selection means (S350 to S380) for selecting data whose importance is lower than a preset threshold value among data recorded in the recording unit as an overwrite target;
With
The data recording apparatus, wherein the recording execution unit overwrites and records data to be recorded on the data selected as the overwriting target according to the recording parameter. In the data recording device according to any one of claims 1 to 8 ,
The degree-of-importance setting means sets an abnormality that makes it difficult for the vehicle to travel in a higher order than an abnormality that is irrelevant to the traveling of the vehicle. The data recording apparatus according to any one of claims 1 to 9 ,
The data recording apparatus, wherein the importance level setting unit sets the importance level higher as the traveling speed of the host vehicle increases. The data recording program for functioning a computer as each means which comprises the data recording device of any one of Claims 1-10 .

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