Method and device for determining a mission profile of a motor vehicle

Abstract

The invention relates to a method for determining data characterizing a mission profile of a motor vehicle. The invention also relates to a computer device (100) implementing such a method. Figure for the abstract: 1

Description

Title of the invention: Method and device for determining a mission profile of a motor vehicle Technical field of the invention

[0001] The present invention relates to the field of computer systems for facilitating the design of motor vehicles. The invention relates in particular to a method for determining data characterizing a mission profile of a motor vehicle. The invention applies to the design of any type of motor vehicle, in particular land motor vehicles such as cars. State of the prior art

[0002] Automobile manufacturers have the constant aim of improving the longevity of vehicles, in particular of reducing the risk of breakdown at least during the first years of use of a vehicle. To achieve these goals, they base the design phase of vehicles and the dimensioning of their components on information, generally known as mission profiles, which provides information on the use made of the vehicles. Traditionally, this information is determined by using test vehicles equipped with means for recording driving data that are entrusted to a certain number of users or by questioning users on the use they make of the vehicles. However, such a way of constituting mission profiles has a certain number of drawbacks, in particular in terms of the reliability of the driving data obtained.Indeed, we cannot be sure that the users who are entrusted with vehicles dedicated to determining mission profiles or that those who are questioned have a use sufficiently representative of the general behavior of all users. Furthermore, we cannot be sure that driving data on the basis of which mission profiles are determined at a given moment remain valid over time since external factors can influence user behavior. Finally, this way of determining mission profiles involves a latency that slows down the design phase of the vehicles and expenses that influence their manufacturing cost. Summary of the invention

[0003] The invention aims to overcome these drawbacks. In particular, one objective of the invention is to provide means for enabling mission profiles to be determined more reliably. The invention also aims to accelerate the ability to determine mission profiles so as to promote the ability to size vehicle components more quickly and thus shorten the duration of the phase of vehicle design. The invention finally aims to reduce the manufacturing cost of vehicles. The invention thus seeks to improve the longevity of vehicles so as to minimize the consumption of raw materials.

[0004] In order to achieve these aims, the invention relates, according to a first aspect, to a method for determining, by a computer device, data characterizing a mission profile of a motor vehicle, the method comprising the steps of: i. obtaining data characterizing occurrences of use of a set of motor vehicles of a pre-established fleet of motor vehicles from data characterizing occurrences of use of the motor vehicles of said fleet of motor vehicles which have been previously received from the motor vehicles of said fleet of motor vehicles; ii. determine, based on the data obtained during step i), a set of criteria characteristic of an occurrence of use of a motor vehicle and a pre-established observation period, data characterizing, for each motor vehicle of said set of motor vehicles, characteristic values ​​of its occurrences of use; iii. determine, on the basis of the data determined during step ii) and pre-established extreme values, data characterizing, for each motor vehicle of said set of motor vehicles, a set of occurrences of use of interest; iv. determine data characterizing, for each occurrence of use of interest, normalized values ​​based on the data obtained during step ii); v. determine, for each vehicle of said set of motor vehicles, data characterizing N occurrences of use of interest selected randomly, N being a pre-established integer; vi. determine, based on the data obtained during step iv), data characterizing, for each characteristic criterion of a use of a motor vehicle, a value of a first percentile established with respect to the occurrences of use of interest and a value of a second percentile established with respect to the N occurrences of use of interest selected randomly vii. determine, for each vehicle of said set of vehicles and each characteristic criterion of the use of a motor vehicle, data characterizing a representativeness error value of the N occurrences of use selected randomly with respect to the occurrences of use of interest; viii. determine, for each vehicle of said set of vehicles, data characterizing a sample of occurrences of acceptable relevance of use based on the data determined during step vii) and a pre-established acceptable representativeness error value; and ix. determine the data characterizing a mission profile of a motor vehicle based on the data determined during step viii).

[0005] According to a variant, the set of criteria characteristic of an occurrence of use of a motor vehicle may comprise a criterion of distance traveled during the occurrence of use, a criterion of acceleration reached during the occurrence of use and a criterion of duration of the occurrence of use.

[0006] According to another variant, said characteristic values ​​of the occurrences of use of a motor vehicle of said set of determined motor vehicles may include a maximum acceleration value reached during each occurrence of use, a value of distance traveled during each occurrence of use and a value of duration of each occurrence of use.

[0007] According to yet another variant, said normalized values ​​can be determined as a function of a maximum acceleration value reached determined with respect to all the occurrences of use of interest, a minimum acceleration value determined with respect to all the occurrences of use of interest, a maximum distance traveled value determined with respect to all the occurrences of use of interest, a minimum distance traveled value determined with respect to all the occurrences of use of interest, a maximum duration value determined with respect to all the occurrences of use of interest and a minimum duration value determined with respect to all the occurrences of use of interest.

[0008] According to yet another variant, step viii) may comprise a step of determining the difference between the value of the second percentile and the value of the first percentile.

[0009] According to yet another variant, step viii) may comprise a step consisting of applying to said difference a pre-established weighting factor with regard to a criterion characteristic of a use of a motor vehicle considered.

[0010] According to yet another variant, step viii) may comprise a step consisting of determining the sum of a representativeness error value established with respect to a first criterion characteristic of a use of a motor vehicle and a representativeness error value established with respect to a second criterion characteristic of a use of a motor vehicle.

[0011] According to yet another variant, said observation period may correspond to one year.

[0012] According to a second aspect, the invention relates to a device for determining data characterizing a mission profile of a motor vehicle, the device comprising at least one information processing unit, comprising at least one processor, and a data storage medium, which are configured to implement a method as described above. Brief description of the figures

[0013] Other characteristics and advantages of the invention will appear on examining the detailed description below, and the appended figures, in which:

[0014] [Fig-1] is a diagram illustrating the context of the invention;

[0015] [Fig.2] is a functional diagram of a device according to the invention; and

[0016] [Fig.3] is a flowchart of the steps of a method according to the invention. Detailed description of the invention

[0017] [Fig.l] schematically illustrates the context of the invention. It shows in particular a device 100 for determining data characterizing a mission profile of a motor vehicle, which implements the method for determining data characterizing a mission profile of a motor vehicle according to the invention described below. The device 100 according to the invention continuously receives, by means of conventional mobile communication networks and protocols (e.g. 3 / 4 / 5G, ITS-G5, C-V2X, etc.), data characterizing occurrences of use of the vehicles of a fleet of vehicles 1, which includes a set of vehicles 2 each corresponding to the vehicle for which the data characterizing a mission profile of a motor vehicle are determined by the device 100 according to the invention during the implementation of the method according to the invention.Preferably, this data characterizing occurrences of use of the vehicles of the vehicle fleet 1 are stored in a database as soon as they are received from the vehicles of the vehicle fleet 1.

[0018] [Fig. 2] illustrates in detail the device 100 according to the invention. It is essentially a computer device, which comprises at least one information processing unit 101, with one or more processors, a data storage medium 102, on which is recorded in particular a program which comprises program code instructions for the execution of the steps of the method according to the invention described below, and an input and output interface 103 allowing the reception and transmission of data.

[0019] According to the invention, all the elements described above contribute to enabling the implementation of a method for determining data characterizing a mission profile of a motor vehicle, as described below in connection with [Fig.2].

[0020] [Fig.2] illustrates by means of a flowchart the steps of the method according to the invention.

[0021] According to a first step 201 of the method according to the invention, the device 100 according to the invention obtains data characterizing occurrences of use of a set of motor vehicles 2 of a fleet of motor vehicles pre-established from data characterizing occurrences of use of the motor vehicles of said fleet of motor vehicles 1 which have been previously received from the motor vehicles of said fleet of motor vehicles 1. Indeed, the device 100 according to the invention permanently receives data characterizing occurrences of use transmitted by each vehicle of the fleet of motor vehicles 1. However, this fleet of vehicles 1 includes in particular a set of vehicles 2 which each correspond to the vehicle for which it is desired to determine the mission profile.Data which identify this set of vehicles 2 relevant for the determination of the mission profile are pre-established and provided to the device 100 according to the invention prior to the implementation of the method, which uses them to extract from among all the data which it receives only those which have been transmitted by the set of vehicles which is relevant for the determination of the mission profile.

[0022] An occurrence of use of a vehicle within the meaning of the invention corresponds to a journey made or, more generally, to any episode of static or mobile use of a vehicle. Thus, the data which are obtained by the device 100 according to the invention during this first step of the method provide information, for example, on a change in speed or acceleration during a journey, a distance traveled during a journey or a time which has elapsed between the activation of the ignition of a vehicle and the switching off of the ignition.

[0023] Thus, at the end of this first step of the method, the device 100 according to the invention holds data transmitted by the set of vehicles 2 which is relevant for determining the mission profile.

[0024] According to a second step 202 of the method according to the invention, the device 100 according to the invention determines, as a function of the data which were obtained during the previous step, of a set of criteria characteristic of an occurrence of use of a motor vehicle and of a pre-established observation duration, which, for example, corresponds to one year, data characterizing, for each motor vehicle of said set of motor vehicles 2, characteristic values ​​of its occurrences of use. According to one embodiment, the criteria characteristic of an occurrence of use of a motor vehicle within the meaning of the invention comprise a criterion of distance traveled during the occurrence of use, a criterion of acceleration reached during the occurrence of use and a criterion of duration of the occurrence of use. Other criteria can be defined according to previously defined needs.Thus, the characteristic values ​​of the usage occurrences which are determined during this second step of the method contain, for example, for each vehicle and for each of its usage occurrences, a maximum acceleration value reached, a distance travelled value and a value. duration of each occurrence of use. Thus, with respect to a vehicle v; of the set of vehicles 2 and one of its occurrences of use j, the device 100 according to the invention determines, for example, values ​​such as v;(j) := [Max acceleration(j); average speed (j); driving time between two pre-established instantaneous speeds (j); duration (j); distance(j)]. The choice of these characteristic values ​​which are determined during this second step is pre-established according to types of values ​​considered relevant for the determination of a mission profile by a person skilled in the art.

[0025] Thus, at the end of this second step, the device 100 according to the invention has processed the data obtained during the first step to derive values ​​which characterize each occurrence of use of each vehicle of the set of vehicles 2 which occurred during the observation period as a function of usage criteria relevant for determining the mission profile.

[0026] According to a third step 203 of the method according to the invention, the device 100 according to the invention determines, as a function of the data determined during the second step and of pre-established extreme values, data characterizing, for each motor vehicle of said set of motor vehicles, a set of usage occurrences of interest. In other words, the device 100 according to the invention carries out during this third step a filtering of the usage occurrences of each vehicle of the set of vehicles 2 as a function of pre-established extreme values ​​in order to retain only some of these usage occurrences which are relevant for the determination of a mission profile. The usage occurrences of interest, those which are retained, are those for which, for example, the duration of the usage occurrence is less than eight hours or the distance traveled during the usage occurrence is non-zero.

[0027] Thus, at the end of this third step, the device 100 according to the invention therefore holds, for each vehicle of the set of vehicles 2, occurrences of use which are a priori the most relevant for determining the mission profile of a vehicle belonging to the set of vehicles 2.

[0028] According to a fourth step 204 of the method according to the invention, the device 100 according to the invention determines data characterizing, for each occurrence of use of interest determined during the previous step and for each vehicle of the set of vehicles 2, normalized values. This step advantageously makes it possible to subsequently compare on the same scale the statistics established with regard to different characteristic criteria of an occurrence of use of a vehicle. To do this, the device 100 according to the invention first establishes, for each vehicle of the set of vehicles 2 and for all its occurrences of use of interest, extrema of the characteristic values ​​which have been previously determined. completed during the second step. Thus, it determines, for example, data characterizing a maximum acceleration value reached determined with respect to all occurrences of use of interest, a minimum acceleration value determined with respect to all occurrences of use of interest, a maximum distance traveled value determined with respect to all occurrences of use of interest, a minimum distance traveled value determined with respect to all occurrences of use of interest, a maximum duration value determined with respect to all occurrences of use of interest and a minimum duration value determined with respect to all occurrences of use of interest.And to obtain the normalized values, the device 100 according to the invention determines, for each characteristic criterion of an occurrence of use of a motor vehicle, a ratio of the difference between the characteristic value and the minimum over all occurrences of use and the difference between the maximum over all occurrences of use of interest and the minimum of the value over all occurrences of use of interest. From the mathematical point of view, the device 100 according to the invention solves the equation below.

[0029] Normalized value = (characteristic value - minimum over all occurrences of use of interest) / (maximum over all occurrences of use of interest - minimum over all occurrences of use of interest).

[0030] Thus, at the end of this fourth step, each occurrence of use of each vehicle of the set of vehicles 2 is characterized by a set of normalized values ​​included in the interval [0; 1].

[0031] According to a fifth step 205 of the method according to the invention, the device 100 according to the invention determines, for each vehicle of said set of motor vehicles 2, data characterizing N occurrences of use of interest selected randomly, N being a pre-established integer. In other words, the device 100 according to the invention determines at this stage, for each vehicle of the set of vehicles 2, a subset of its occurrences of use of interest which were determined during the third step of the method.

[0032] According to a sixth step 206 of the method according to the invention, the device 100 according to the invention determines, as a function of the data obtained during the previous step, data characterizing, for each characteristic criterion of a use of a motor vehicle considered, a value of a first percentile established with respect to the occurrences of use of interest and a value of a second percentile established with respect to the N occurrences of use of interest selected randomly. In other words, for each vehicle of the set of vehicles 2 and for each characteristic criterion of an occurrence of use considered i, the device 100 according to the invention determines a value of a percentile Ci established with respect to all the occurrences of use of interest selected randomly. interest usage occurrences and a percentile value Cr, established with respect to only the interest usage occurrences randomly selected during the previous step.

[0033] According to a seventh step 207 of the method according to the invention, the device 100 according to the invention determines, for each vehicle of said set of vehicles and each characteristic criterion of the use of a motor vehicle, data characterizing a representativeness error value of the N randomly selected occurrences of use of interest with respect to all the occurrences of use of interest. Indeed, the device 100 according to the invention seeks at this stage to determine, for each vehicle of the set of vehicles 2 and for each characteristic criterion of the use of a motor vehicle, the representativeness of the N randomly selected occurrences of use of interest with respect to all the occurrences of use of interest. Otherwise, it seeks to determine whether the N randomly selected occurrences of interest are relevant for determining the mission profile.To do this, it calculates the difference between the value of a percentile established with respect to only the randomly selected occurrences of use of interest Crt and the value of a percentile established with respect to all occurrences of use of interest Ci.

[0034] According to an eighth step 208 of the method according to the invention, the device 100 according to the invention determines, for each vehicle of said set of vehicles 2, data characterizing a sample of occurrences of use of acceptable relevance as a function of the data determined during the previous step and of a pre-established acceptable representativeness error value. To do this, it preferentially applies to the difference determined during the step a pre-established weighting factor Wi with respect to a characteristic criterion of an occurrence of use of a motor vehicle, which advantageously makes it possible to give more or less importance to one criterion or another, and it adds together the values ​​obtained for all the characteristic criteria of a use of a vehicle considered.From a mathematical point of view, the device 100 according to the invention determines the overall representativeness error with regard to all the characteristic criteria of the use of a vehicle by solving the equation below.

[0035] criteria? Representativeness error - ot,- ■ ( Crf -C^

[0036] And if it establishes that the representativeness error is greater than the pre-established acceptable representativeness error value, which means that the representativeness of the N randomly selected occurrences of interest is not acceptable, the device 100 according to the invention repeats the three previous steps (i.e. random selection, calculation of percentiles, calculation of the difference of the percentiles) as well as this seventh step until that this is the case. At the end of this eighth step, the device 100 according to the invention has thus established, for each vehicle of the set of vehicles 2, a sample of occurrences of use of acceptable relevance.

[0037] According to a ninth step 209 of the method according to the invention, the device 100 according to the invention determines the data characterizing a mission profile of a motor vehicle as a function of the data determined during the previous step. In other words, it is as a function of the samples of occurrences of use of acceptable relevance determined during the previous step for each vehicle of the vehicle set 2 that the device 100 according to the invention finally determines the mission profile of the vehicle. The mission profile of the vehicle thus determined is therefore based on occurrences of use which best represent the behavior of the users of the vehicles of the vehicle set 2.

[0038] Thus, thanks to the method and the system according to the invention described above, a solution is provided for determining mission profiles more reliably. The ability to determine mission profiles is also accelerated so that the components of a vehicle can be dimensioned more quickly and thus shorten the duration of the vehicle design phase. By allowing the determination of mission profiles in an automated manner, the expenses related to this need of manufacturers, which influence the manufacturing cost of the vehicles, are also reduced. Thanks to these means, the longevity of the vehicles is improved and thus the consumption of raw materials is minimized.

Claims

1. Claims Method for determining, by a computer device, data characterizing a mission profile of a motor vehicle, characterized in that the method comprises the steps of: i. obtaining data characterizing occurrences of use of a set of motor vehicles of a pre-established fleet of motor vehicles from data characterizing occurrences of use of the motor vehicles of said fleet of motor vehicles which have been previously received from the motor vehicles of said fleet of motor vehicles; ii. determine, based on the data obtained during step i), a set of criteria characteristic of an occurrence of use of a motor vehicle and a pre-established observation duration, data characterizing, for each motor vehicle of said set of motor vehicles, characteristic values ​​of its occurrences of use; iii. determine, on the basis of the data determined during step ii) and pre-established extreme values, data characterizing, for each motor vehicle of said set of motor vehicles, a set of occurrences of use of interest; iv. determine data characterizing, for each occurrence of use of interest, normalized values ​​based on the data obtained during step ii); v. determine, for each vehicle of said set of motor vehicles, data characterizing N occurrences of use of interest selected randomly, N being an integer; vi. determine, based on the data obtained during step iv), data characterizing, for each characteristic criterion of a use of a motor vehicle, a value of a first percentile established with respect to the occurrences of use of interest and a value of a second percentile established with respect to the N occurrences of use of interest selected randomly; vii. determining, for each vehicle of said set of vehicles and each characteristic criterion of the use of a motor vehicle, data characterizing a representativeness error value of the N randomly selected use occurrences with respect to the use occurrences of interest; viii. determining, for each vehicle of said set of vehicles, data characterizing a sample of use occurrences of acceptable relevance based on the data determined during step vii) and a pre-established acceptable representativeness error value; and ix. determining the data characterizing a mission profile of a motor vehicle based on the data determined during step viii).

2. Method according to claim 1, characterized in that the set of criteria characteristic of an occurrence of use of a motor vehicle comprises a criterion of distance traveled during the occurrence of use, a criterion of acceleration reached during the occurrence of use and a criterion of duration of the occurrence of use.

3. Method according to one of the preceding claims, characterized in that said characteristic values ​​of the occurrences of use of a motor vehicle of said set of determined motor vehicles include a maximum acceleration value reached during each occurrence of use, a value of distance traveled during each occurrence of use and a value of duration of each occurrence of use.

4. Method according to one of the preceding claims, characterized in that said normalized values ​​are determined as a function of a maximum acceleration value reached determined with respect to all the occurrences of use of interest, a minimum acceleration value determined with respect to all the occurrences of use of interest, a maximum distance traveled value determined with respect to all the occurrences of use of interest, a minimum distance traveled value determined with respect to all the occurrences of use of interest, a maximum duration value determined with respect to all the occurrences of use of interest and of a minimum duration value determined with respect to all occurrences of use of interest.

5. Method according to one of the preceding claims, characterized in that step viii) comprises a step consisting of determining the difference between the value of the second percentile and the value of the first percentile.

6. Method according to claim 5, characterized in that step viii) comprises a step consisting of applying to said difference a pre-established weighting factor with regard to a characteristic criterion of a use of a motor vehicle considered.

7. Method according to one of the preceding claims, characterized in that step viii) comprises a step consisting of determining the sum of a representativeness error value established with respect to a first criterion characteristic of a use of a motor vehicle and a representativeness error value established with respect to a second criterion characteristic of a use of a motor vehicle.

8. Method according to one of the preceding claims, characterized in that said observation duration corresponds to one year.

9. Device (100) for determining data characterizing a mission profile of a motor vehicle, characterized in that said device comprises at least one information processing unit (101), comprising at least one processor, and a data storage medium (102), which are configured to implement a method according to any one of the preceding claims.

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