Device and computer-implemented method for providing a synthetic logbook for testing a vehicle component or a vehicle

Abstract

The invention relates to a device and a computer-implemented method for providing a synthetic logbook for testing a vehicle component or a vehicle, wherein from a distribution across values of a variable which characterises a logbook entry, a value of the variable is drawn in particular at random (302), wherein the distribution represents values of the variable measured during journeys with real vehicles, preferably including journeys undertaken on different days, or is based on assumptions about values of the variable which would be measurable during journeys with real vehicles, preferably including journeys undertaken on different days, wherein for a journey, an entry which comprises the value is stored in the synthetic logbook (304), and the synthetic logbook containing the entry is provided (308).

Description

[0001] Description

[0002] title

[0003] Device and computer-implemented method for providing a synthetic logbook for testing a vehicle component or a vehicle

[0004] State of the art

[0005] The invention is based on a device and a computer-implemented method for providing a synthetic logbook for testing a vehicle component or a vehicle.

[0006] Disclosure of the invention

[0007] The device and the computer-implemented method for providing a synthetic logbook for testing a vehicle component or a vehicle according to the independent claims estimate synthetic logbooks from a small number of available or assumed mobility data in a region for a large number of users in the same region. The synthetic logbooks can be used, in particular, to estimate load distribution through simulation.

[0008] When it comes to determining the load distribution in the field, each user makes different journeys, meaning each user has a different logbook. This results in a different load for each user, meaning a different load spectrum. The load spectrum of all users leads to a load distribution in the field.

[0009] In some regions, user logbooks are available. However, in some regions, the user logbooks are unknown. In some regions, mobility distributions are available instead of logbooks. A mobility distribution indicates, for example, how a driver's trip lengths are distributed over their usage time. However, an assignment to the departure time is missing. The mobility distributions are obtained, for example, through measurements or surveys. If no mobility distributions are available, an assumption about the mobility distributions can be made. The mobility distribution is based on values ​​of variables that are characteristic of a logbook entry, measured during trips with real vehicles.

[0010] The computer-implemented method for providing a synthetic logbook for testing a vehicle component or a vehicle provides that a value of the variable is drawn, in particular randomly, from a distribution over values ​​of a variable that is characteristic of a logbook entry, wherein the distribution represents values ​​of the variable measured during journeys with real vehicles, preferably including journeys made on different days, or is based on assumptions about values ​​of the variable that would be measurable during journeys with real vehicles, preferably including journeys made on different days, wherein an entry comprising the value is stored in the synthetic logbook for a journey, and the synthetic logbook is provided with the entry. The testing comprises, for example, a test of the vehicle or the vehicle component.It may be intended to use the synthetic logbook as an input value for calculating an equivalent value. This value can be used, for example, to define a test or to compare different logbooks, particularly synthetic or actually measured ones. The method offers a Monte Carlo approach for generating the synthetic logbook. The synthetic logbook is based on real measurements or on assumptions about the measurements. The measurement of the distributions or assumptions about the distributions can, for example, be made in a market and used to generate synthetic logbooks in the same market for which few or only incomplete logbooks are available.The journeys, which preferably take place on different days, can be several self-contained journeys which take place at least in part on different days, and / or several journeys of a joint multi-day trip which take place at least in part on several consecutive days. Preferably, the distribution represents measured values ​​of the quantity for journeys with real vehicles including, preferably exclusively, on different consecutive days, or is based on assumptions about values ​​of the quantity that would be measurable for journeys with real vehicles including, preferably exclusively, different consecutive days. The use of such multi-day, aggregated data advantageously enables improved consideration of correlations and causal relationships between consecutive days.According to a particular embodiment, the distribution represents or includes values ​​of the quantity that were measured with real vehicles on several, at least partially different, days and / or trips lasting several days, or is based on assumptions about such values.

[0011] The size characterizes, for example, a journey length, a journey duration, a week number, a departure time, or a departure day.

[0012] It can be provided that the entry for the trip length and / or the trip duration is determined for the trip, with the entry for the week number and / or the departure time and / or the departure day being determined for the trip. A trip characterized by these entries makes it possible to generate a synthetic logbook for meaningful testing of a vehicle component or a vehicle with the least possible resource expenditure for determining and storing the synthetic logbook.

[0013] It can be provided that the entries are each determined from a respective distribution or that several of the entries are determined from a common multi-dimensional distribution, in particular that the departure time and the departure day are determined from a two-dimensional distribution of departure time and departure day. This means that the method processes individual distributions or multi-dimensional distributions or both. In an exemplary embodiment, a number of trips in a period is specified or, in particular, a number of trips in the period is randomly drawn from a distribution over the number of trips in a period, wherein the entry is determined in each case for the number of trips in the period and the entries determined for the number of trips in the period are stored in the synthetic logbook, wherein the synthetic logbook is provided with the entries for the number of trips in the period.

[0014] It can be provided that a length of the period is specified or, in particular, randomly drawn from a distribution of lengths of the period, whereby the synthetic logbook is provided for the length of the period. This means that the method provides a synthetic logbook for a variable period in which the test is carried out.

[0015] It may be provided that the entry for the trip is saved in the logbook in a randomly determined order with an entry for another trip.

[0016] It can be provided that, depending on the journey duration characterized by the extracted variable, the departure time characterized by the extracted variable, and the departure date characterized by the extracted variable, and depending on an entry for the journey duration, an entry for the departure time, and an entry for the departure date of another journey from the synthetic logbook, a check is carried out to determine whether there is a temporal overlap between the journey and the other journey. If there is a temporal overlap, no entry for the journey is saved in the logbook, or the entries for the other journey are deleted from the logbook, or at least one of the entries is changed such that there is no temporal overlap. This cleans up the synthetic logbook of entries that are unsuitable for testing.

[0017] It can be provided that an average driving speed is determined based on the entries for the journey duration and length of multiple journeys. For a single journey, a driving speed is determined based on the entry for the journey duration and length of the journey. The entry for the journey duration or length is corrected if the driving speed of the journey deviates from the average driving speed by more than a specified speed value. This avoids entries that lead to implausible driving speeds.

[0018] In one exemplary embodiment, the test is carried out using at least one trip from the synthetic logbook. It may be provided to use the synthetic logbook as an input value for calculating a value for defining a test or for comparing different, in particular synthetic or actually measured, logbooks.

[0019] A device for providing a synthetic logbook for testing a vehicle component or a vehicle, in particular for testing the vehicle component or the vehicle or for calculating a value for defining a test or for comparing different, in particular synthetic or actually measured, logbooks, comprises at least one processor and at least one memory, wherein the at least one memory comprises instructions executable by the at least one processor, upon execution of which instructions by the at least one processor, the device carries out the method.

[0020] A computer program comprises computer-readable instructions which, when executed by a computer, carry out on the computer the method for providing a synthetic logbook for testing a vehicle component or a vehicle.

[0021] A data structure for providing a synthetic logbook for testing a vehicle component or a vehicle provides that the data structure comprises data fields, wherein the data structure encodes in at least one of the data fields a distribution over values ​​of a quantity that is characteristic of a logbook entry, from which a value of the quantity can be drawn, in particular randomly, wherein the distribution represents values ​​of the quantity measured during journeys with real vehicles, preferably including journeys carried out on different, in particular consecutive, days, or is based on assumptions about values ​​of the quantity that would be measurable during journeys with real vehicles, preferably including journeys carried out on different, in particular consecutive, days, wherein the data structure encodes the synthetic logbook in several of the data fields, wherein one of the data fields comprises an entry that encodes the value of the quantity.

[0022] Further advantageous embodiments can be found in the following description and the drawing. The drawing shows:

[0023] Fig. 1 is a schematic representation of a device for providing a synthetic logbook for testing,

[0024] Fig. 2 exemplary distributions of a characteristic value for a logbook,

[0025] Fig. 3 is a flowchart showing steps of a method for providing the synthetic logbook for testing.

[0026] Figure 1 schematically shows a device 100 for providing a synthetic logbook for testing.

[0027] The device 100 comprises at least one processor 102 and at least one memory 104.

[0028] The at least one memory 104 comprises instructions executable by the at least one processor 102, upon execution of which instructions by the at least one processor 102, the device 100 executes a method for providing the synthetic logbook for testing.

[0029] The device 100 comprises, for example, a computer. A computer program executable by the computer comprises, for example, the instructions.

[0030] Figure 2 shows exemplary distributions of a characteristic variable for a logbook.

[0031] In the example, the testing is carried out over a period of time.

[0032] A first distribution 202 is a distribution across possible week numbers for departure. In the example, the first distribution 202 is a uniform distribution. A second distribution 204 is a distribution across departure days.

[0033] In the example, exemplary relative frequencies of trips on Mondays, Tuesdays, Wednesdays, Thursdays, Fridays, Saturdays and Sundays are shown as bars in this order from left to right.

[0034] A third distribution 206 is a distribution across departure times. In the example, the departure time is distributed across times between midnight and midnight. In the example, the frequency of the departure time is higher during the day than at night.

[0035] A fourth distribution, 208, is a distribution of trip lengths. In the example, the trip lengths are given in kilometers. In the example, shorter trip lengths are more common than longer trip lengths.

[0036] A fifth distribution 210 is a distribution of travel times. In the example, the travel times are given in minutes. In the example, shorter travel times are more common than longer travel times.

[0037] These distributions are examples of distributions of values ​​of a quantity that are characteristic of a logbook for a test.

[0038] Other sizes suitable for a test logbook may be provided. Other value formats may be provided.

[0039] The distributions are based on measurements or assumptions about them. The respective distribution represents measured values ​​of the respective quantity during journeys with real vehicles on different days or an assumption about values ​​of the quantity that would be measurable during journeys with real vehicles on different days.

[0040] In one example, the distributions are based on measured values ​​measured on different consecutive days. In one example, the distributions are based on assumptions about the values ​​that would be measurable on different consecutive days. The values ​​represent mobility data. The distributions are measured or assumed distributions of mobility data.

[0041] Two-dimensional or multidimensional distributions of values ​​of different sizes can be provided. For example, a two-dimensional distribution of departure time and departure day is provided.

[0042] Figure 3 shows a flowchart illustrating the steps of the method for preparing the synthetic logbook for testing. The method involves determining a trip in the synthetic logbook. The method is described using the example of a user with a predefined user ID. For a synthetic logbook that includes trips from multiple users, different user IDs are predefined or drawn from a distribution.

[0043] The method provides synthetic logbooks of different users using a Monte Carlo approach based on the measured or assumed distributions of mobility data. This allows a load spectrum distribution, which is important for reliability design, to be simulated much more accurately in situations where data availability is poor, making the use of real logbooks difficult or impossible.

[0044] In the example, the synthetic logbook includes an entry for each trip within a period, specifying the length, duration, departure time, and departure date. The period is divided into weeks. In the example, the synthetic logbook includes an entry for each trip indicating the week of the period in which the trip takes place. The synthetic logbook may include a unique trip identification for each trip. The synthetic logbook may include trips by different users, each identified by a unique user identification. An example synthetic logbook includes the following entries for each trip:

[0045] User identification, trip identification, week, day of the week, departure time, trip length, trip duration. The method includes a step 300.

[0046] In step 300, a period length is specified or drawn from a distribution of period lengths. In the example, the length is specified.

[0047] The length of the period is, for example, 52 weeks.

[0048] In step 300, a number of trips is specified or drawn from a distribution of the number of trips in the period. In the example, the number is randomly drawn from the distribution of numbers.

[0049] The number of trips is e.g. 400.

[0050] The method includes a step 302.

[0051] In step 302, a value of the respective variable is drawn from the respective distribution. The respective value is drawn randomly, for example.

[0052] In the example, values ​​for the variables trip length, trip duration, departure time, and departure day are drawn. It may be specified not to draw each of these variables. It may be specified to predefine one or more of these variables or not to use them.

[0053] It can be provided that a two-dimensional distribution of departure time and departure day is determined from the two-dimensional distribution of departure time and departure day.

[0054] In the example, the entry for the departure day is determined for the trip.

[0055] In the example, the entry for the departure time is determined for the trip.

[0056] In the example, the entry for the journey length is determined for the journey.

[0057] In the example, the entry for the journey duration is determined for the journey.

[0058] In the example, the entries are each determined from a respective distribution. It is possible to specify that several of the entries are determined from a common multidimensional distribution. It is possible to specify that the entries are drawn from user-specific distributions.

[0059] This allows correlations and causal relationships to be better considered. This allows the spread of a load spectrum distribution, which is important for reliability design, to be simulated much more accurately.

[0060] Step 304 is then executed.

[0061] In step 304, the entries for the trip, which include the respective value of the quantity, are stored in the synthetic logbook.

[0062] For example, the entries for this trip are stored in a randomly determined order with the entries for another trip in the logbook. Trip identification, for example, determines the order by consecutively numbering the trips.

[0063] In the example, the trips are randomly distributed over the period. For example, the week in which the trip takes place is randomly drawn from distribution 202. It may be planned to assume an even distribution of the possible week numbers for the week selection. For example, for a period of 52 weeks, the week number is determined between 1 and 52.

[0064] In the example, the user identification, the trip identification, the week, the day of the week, i.e. the departure day, the departure time, the trip length and the trip duration are stored.

[0065] It may be provided to repeat steps 302 to 304 for the number of trips. This means that the entry is determined for the number of trips in the period, and the entries for the number of trips in the period are stored in the synthetic logbook. This means that the synthetic logbook is provided with the entries for the number of trips in the period.

[0066] The method comprises a step 306. In step 306, for each of the trips of a user identification, depending on the trip duration characterized by the extracted variable and the departure characterized by the extracted variables (week number, departure day, departure time) and depending on an entry for the trip duration and an entry for the departure (week number, departure day, departure time) of another trip from the synthetic logbook, it is checked whether there is a temporal overlap of the trip with the other trip.

[0067] If there is a temporal overlap, for example, the entries of the other trip are deleted from the logbook, or at least one of the entries of the trip or the other trip is changed in such a way that there is no temporal overlap.

[0068] Alternatively, it can be provided that no entry is saved for the trip if there is a time overlap.

[0069] It can be provided that an average driving speed is determined depending on the entries for the journey duration and the journey length of several journeys. It can be provided that a driving speed is determined during the journey depending on the entry for the journey duration and the journey length of the journey. It can be provided that the entry for the journey duration or the journey length is corrected if the driving speed of the journey deviates from the average driving speed by more than a predetermined speed value. For example, the driving speed of the journey is reduced by increasing the journey duration or reducing the journey length if the driving speed of the journey is higher than the average driving speed by more than the predetermined speed.For example, if the speed of the trip is lower than the average speed by more than the specified speed, the speed of the trip is increased by reducing the trip duration or increasing the trip length. In this example, the speed is adjusted so that it is within the range of the specified speed around the average speed.

[0070] The method comprises a step 308. In step 308, the synthetic logbook with the entry is provided.

[0071] The synthetic logbook is provided, for example, for the length of the period.

[0072] Optionally, the test is carried out with at least one trip from the synthetic logbook.

[0073] It may be intended to use the synthetic logbook as an input value for calculating an equivalent value. This value can be used, for example, to define a test or to compare different synthetic or real-world measured logbooks.

[0074] It may be planned to store the synthetic logbook in a database of a simulation program for a virtual measurement campaign. It may be planned to use the synthetic logbook to estimate a load spectrum distribution.

[0075] It may be planned to conduct testing using synthetic logbooks for a market with poor data availability. This allows a virtual measurement campaign to be conducted even for countries with poor data availability, where the use of real logbooks is difficult or impossible. This allows the load spectrum distribution to be estimated using simulations even in the early stages, when no measured field data is available. The testing can cover a single vehicle component or a single vehicle. The risk of over- or under-dimensioning a vehicle component is reduced.

[0076] It may be possible to define multiple synthetic logbooks for multiple users. It may be possible for a synthetic logbook to be composed of synthetic logbooks from multiple users, each identified by a different user identification.

[0077] The synthetic logbooks of individual users do not have to exactly match individual real logbooks. The random process ensures that the total set of synthetic logbooks resembles the total set of real logbooks, and the load spectrum distribution sought for component design is realistically estimated across the synthetic logbooks.

[0078] A data structure may be provided to provide the synthetic logbook for testing the vehicle component or the vehicle.

[0079] The data structure includes, for example, data fields. The data structure encodes, in at least one of the data fields, the distribution over values ​​of the quantity that is characteristic of the logbook entry.

[0080] A value of the size can be drawn randomly from the distribution in the data structure.

[0081] The distribution in the data structure represents values ​​of the quantity measured during journeys with real vehicles or is based on assumptions about values ​​of the quantity measured during journeys with real vehicles.

[0082] The data structure encodes the synthetic logbook in several data fields. One of the data fields contains an entry that encodes the value of the variable.

Claims

Claims 1. A computer-implemented method for providing a synthetic logbook for testing a vehicle component or a vehicle, characterized in that a value of the variable is drawn, in particular randomly (302), from a distribution (204, 206, 208) over values ​​of a variable that is characteristic of a logbook entry, wherein the distribution (204, 206, 208) represents values ​​of the variable measured during journeys with real vehicles, preferably including journeys made on different days, or is based on assumptions about values ​​of the variable that would be measurable during journeys with real vehicles, preferably including journeys made on different days, wherein an entry comprising the value is stored in the synthetic logbook for a journey (304), and the synthetic logbook is provided with the entry (308).

2. Method according to claim 1, characterized in that the distribution (204, 206, 208) represents values ​​of the quantity measured during journeys with real vehicles carried out including, preferably exclusively, on different consecutive days, or is based on assumptions about values ​​of the quantity that would be measurable during journeys with real vehicles carried out including, preferably exclusively, on different consecutive days.

3. Method according to claim 1 or 2, characterized in that the variable characterizes a journey length, a journey duration, a week number, a departure time, or a departure day.

4. Method according to claim 3, characterized in that the entry for the journey length and / or the journey duration is determined (302) for the journey, wherein the entry for the week number and / or the departure time and / or the departure day is determined (302) for the journey.

5. Method according to claim 4, characterized in that the entries are each determined from a respective distribution (204, 206, 208) or that several of the entries are determined from a common multi-dimensional distribution (302), in particular that the departure time and the departure day are determined from a two-dimensional distribution of departure time and departure day.

6. Method according to one of the preceding claims, characterized in that a number of journeys in a period is predetermined or a number of journeys in the period is drawn, in particular randomly (300), from a distribution over numbers of journeys in a period, wherein the entry is determined in each case for the number of journeys in the period and the entries determined for the number of journeys in the period are stored in the synthetic logbook, wherein the synthetic logbook is provided with the entries for the number of journeys in the period (308).

7. The method according to claim 6, characterized in that a length of the period is predetermined or is drawn, in particular randomly, from a distribution over lengths of the period (300), wherein the synthetic logbook is provided for the length of the period (308).

8. Method according to one of the preceding claims, characterized in that the entry for the journey is stored in a randomly determined order with an entry for another journey in the logbook (304).

9. Method according to one of the preceding claims, characterized in that depending on the journey duration characterized by the extracted variable, the departure time characterized by the extracted variable and the departure day characterized by the extracted variable and depending on an entry for the journey duration, an entry for the departure time and an entry for the departure day of another journey from the synthetic logbook, it is checked (306) whether there is a temporal overlap between the journey and the other journey, wherein if there is a temporal overlap, no entry for the journey is saved in the logbook or the entries for the other journey are deleted from the logbook, or at least one of the entries is changed (306) in such a way that there is no temporal overlap.

10. Method according to one of the preceding claims, characterized in that an average driving speed is determined depending on the entries for the journey duration and the journey length of several journeys, wherein for a journey a driving speed is determined depending on the entry for the journey duration and the journey length of the journey, wherein the entry for the journey duration or the journey length is corrected (306) if the driving speed of the journey deviates from the average driving speed by more than a predetermined speed value 11. Method according to one of the preceding claims, characterized in that the test is carried out with at least one trip from the synthetic logbook (308) or that the synthetic logbook is used as an input value for calculating a value for defining a test or for comparing different, in particular synthetic or actually measured, logbooks.

12. Device (100) for providing a synthetic logbook for testing a vehicle component or a vehicle, in particular for testing the vehicle component or the vehicle or for calculating a value for defining a test or for comparing different, in particular synthetic or actually measured, logbooks, characterized in that the device (100) comprises at least one processor (102) and at least one memory (104), wherein the at least one memory (104) comprises instructions executable by the at least one processor (102), upon execution of which instructions by the at least one processor (102), the device (100) carries out the method according to one of claims 1 to 11.

13. A computer program, characterized in that the computer program comprises computer-readable instructions, the execution of which by a computer on the computer carries out the method according to one of claims 1 to 11.

14. Data structure for providing a synthetic logbook for testing a vehicle component or a vehicle, characterized in that the data structure comprises data fields, wherein the data structure encodes in at least one of the data fields a distribution (204, 206, 208) over values ​​of a quantity which is characteristic of a logbook entry, from which a value of the quantity can be drawn, in particular randomly, wherein the distribution (204, 206, 208) is carried out at, preferably including on different, in particular consecutive days A, represents values ​​of the quantity measured during journeys with real vehicles or is based on assumptions about values ​​of the quantity that would be measurable during journeys with real vehicles, preferably including journeys made on different, in particular consecutive, days, wherein the data structure encodes the synthetic logbook in several of the data fields, wherein one of the data fields comprises an entry that encodes the value of the quantity.

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