Method for evaluating the accuracy of a temperature measurement of the outside air of a motor vehicle.

Abstract

Method for evaluating the accuracy of a monitoring system for a motor vehicle battery cooling system; Method for evaluating the accuracy of an outside air temperature measurement of a motor vehicle, comprising: • a step of collecting observational data including: o a date and time of measurement of an outside temperature, o a temperature measured by a temperature sensor fitted to the vehicle, o a geographical position of the vehicle at the date and time of measurement determined by a vehicle geolocation system; • a step of acquiring a reference temperature provided by a meteorological service provision system, the reference temperature being determined based on the geographical position of the observational data and based on the date and time of the observational data; • then,a step comparing the difference between the temperature of the observed data and the reference temperature to a predefined threshold. Figure for the abstract: 1,

Description

Title of the invention: Method for evaluating the accuracy of a measurement of the temperature of the outside air of a motor vehicle.

[0001] The invention relates to a method for evaluating the accuracy of a measurement of the temperature of the outside air of a motor vehicle.

[0002] Measurements of the temperature of air outside the vehicle are frequently used for the operation of vehicle equipment, for example for the operation of air conditioning in the vehicle's passenger compartment.

[0003] For this purpose, vehicles are generally equipped with at least one temperature sensor capable of measuring an outside air temperature.

[0004] However, measurements from a sensor onboard the vehicle may be inaccurate in certain vehicle usage scenarios, for example, when the vehicle is parked in the sun. In this case, the lack of measurement accuracy can disrupt the operation of the vehicle's equipment. Furthermore, sensor aging can lead to measurement errors, including a significantly systematic shift in the measurements taken by the temperature sensor.

[0005] Alternative means of determining outside air temperature exist, for example, the use of remote weather service provision systems. However, determining the temperature of air outside the vehicle cannot depend solely on a device external to the vehicle. Indeed, there are vehicle use cases in which the vehicle's outside temperature cannot be provided by a remote service. This is the case, for example, when the vehicle is parked in a garage or traveling in a tunnel.

[0006] The object of the invention is to provide a method for evaluating the accuracy of an outside air temperature measurement of a motor vehicle, overcoming the above drawbacks and improving upon prior art methods for evaluating the accuracy of an outside air temperature measurement of a motor vehicle. In particular, the invention makes it possible to implement a simple and reliable method for evaluating and improving the accuracy of an outside temperature measurement.

[0007] To this end, the invention relates to a method for evaluating the accuracy of a measurement of the outside air temperature of a motor vehicle, comprising: • a step of collecting observational data including: o a date and time of measurement of an outside temperature, o a temperature measured by a temperature sensor fitted to the motor vehicle, o a geographical position of the motor vehicle at the date and time of measurement determined by a motor vehicle geolocation system, • a step of acquiring a reference temperature provided by a meteorological service delivery system, the reference temperature being determined based on the geographical location of the observation data and based on the date and time of the observation data, • then, a step of comparing a difference between the temperature of the observation data and the reference temperature to a predefined threshold.

[0008] In one embodiment, each observation data point of the motor vehicle further includes - a vehicle state defined as being parked with the engine off, parked with the engine running, or in motion, and / or - a level of sunlight measured by a sunlight sensor on the vehicle, and / or - the longitudinal speed of the motor vehicle, and the comparison step includes detection, based on the vehicle's condition and / or the level of sunlight and / or the longitudinal speed and / or the vehicle's location, - of a vehicle situation of a first type, in which the vehicle is located in a dark space, particularly in a garage, covered parking lot or tunnel, and - of a situation of the vehicle as being of a second type, in which the vehicle is parked in the sun.

[0009] In one embodiment, the evaluation method further includes a step of determining the accuracy of a temperature measurement, comprising, when the vehicle is in a situation of the first type at the time of measurement, a determination of the accuracy of a temperature measurement as being indefinite; when the vehicle is in a situation of the second type at the time of measurement, a determination of the accuracy of the temperature measurement as being: o of a first level of accuracy if an absolute value of a difference between the temperature measurement and the reference temperature is less than or equal to a first threshold, in particular less than or equal to 4 degrees; o otherwise, of an insufficient level of accuracy. otherwise, a determination of the accuracy of the temperature measurement as being of a second level of accuracy if an absolute value of a difference between the temperature measurement and the reference temperature is less than or equal to a second threshold, in particular less than or equal to 2 degrees, or otherwise, of an insufficient level of precision, the first threshold being greater than or equal to the second threshold.

[0010] In one embodiment, the acquisition, comparison and determination steps are executed by a centralized system communicating with the motor vehicle, and the method includes reception by the centralized system of observation data transmitted by the motor vehicle.

[0011] The invention further relates to a method for improving the accuracy of an outside temperature measurement of a motor vehicle, comprising: - a step of evaluating the accuracy of an outside air temperature measurement according to the invention, - a step of detecting a substantially constant difference, on the different observation data recorded by the motor vehicle, between an outside air temperature measured by the vehicle and a reference temperature provided by a meteorological service provision system, - then, if a substantially constant difference is detected, a step of systematically correcting the outside air temperatures measured by the vehicle according to the substantially constant difference detected.

[0012] In one embodiment, the improvement process includes acquisition, comparison and determination steps performed by a centralized system communicating with the motor vehicle; the process is performed by a centralized system communicating with the motor vehicle, and the systematic correction step includes a transmission to the motor vehicle of a systematic correction to be applied by the motor vehicle to the measured temperatures.

[0013] The invention further relates to a method for improving the accuracy of an outside temperature measurement of a set of motor vehicles, comprising: - a step of evaluating the accuracy of an outside air temperature measurement according to the invention, applied to each vehicle in the set; - a step of detecting a substantially constant difference, on the different observation data recorded by the vehicles in the set, between a temperature measured by a vehicle in the set and a reference temperature provided by a meteorological service provision system; - then, if a substantially constant difference is detected, a step of systematically correcting, by the vehicles in the set, the measured temperatures according to the substantially constant difference detected.

[0014] The invention further relates to a motor vehicle comprising the hardware and software means for implementing the steps of the evaluation process according to the invention and / or the steps of a process for improving the accuracy of a measurement of an outside temperature of a motor vehicle according to the invention, and / or the steps of a method for improving the accuracy of a measurement of an outside temperature of a set of motor vehicles according to the invention.

[0015] The invention further relates to a device for evaluating the accuracy of a measurement of the outside air temperature of a motor vehicle, the device comprising hardware and / or software elements implementing the method for evaluating the accuracy of a measurement of the outside air temperature of a motor vehicle according to the invention, in particular hardware and / or software elements designed to implement the method for evaluating the accuracy of a measurement of the outside air temperature of a motor vehicle according to the invention, and / or the device comprising means for implementing the method for evaluating the accuracy of a measurement of the outside air temperature of a motor vehicle according to the invention.

[0016] The invention further relates to a device for improving the accuracy of a measurement of the temperature of the outside air of a motor vehicle, the device comprising hardware and / or software elements implementing the method for improving the accuracy of a measurement of the temperature of the outside air of a motor vehicle according to the invention, in particular hardware and / or software elements designed to implement the method for improving the accuracy of a measurement of the temperature of the outside air of a motor vehicle according to the invention, and / or the device comprising means for implementing the method for improving the accuracy of a measurement of the temperature of the outside air of a motor vehicle according to the invention.

[0017] The invention further relates to a device for improving the accuracy of a measurement of the outside air temperature of a group of vehicles, the device comprising hardware and / or software elements implementing the method for improving the accuracy of a measurement of the outside air temperature of a group of vehicles, in particular hardware and / or software elements designed to implement the method for improving the accuracy of a measurement of the outside air temperature of a group of vehicles, and / or the device comprising means for implementing the method for improving the accuracy of a measurement of the outside air temperature of a group of vehicles.

[0018] The attached drawing represents, by way of example, an embodiment of an evaluation device according to the invention and an execution method of an evaluation process according to the invention.

[0019] Fig. 1 illustrates a high-level architecture of an enhancement device according to the invention.

[0020] The [Fig.2] is a flowchart of an execution method of a method for evaluating the accuracy of a measurement of an outside temperature of a motor vehicle according to the invention.

[0021] The [Fig.3] is a flowchart of an execution method of a method for improving the accuracy of an external temperature measurement of a motor vehicle according to the invention.

[0022] The [Fig.4] is a flowchart of an execution method of a method for improving the accuracy of an external temperature measurement of a set of motor vehicles according to the invention.

[0023] An example of a first embodiment of a device 80 for evaluating the accuracy of a measurement of an outside air temperature of a motor vehicle is described below with reference to [Fig.1].

[0024] In the first embodiment, the device 80 includes a centralized evaluation system 70 communicating with a local processing system 60 embedded in each of the vehicles 101, 102, 103 of a first set 100 of vehicles.

[0025] The first set of 100 vehicles may also be referred to as "fleet 100" in the remainder of the document.

[0026] The motor vehicles 101, 102, 103 of the fleet 100 can be a motor vehicle of any type, including a passenger vehicle, a utility vehicle, a truck or a public transport vehicle such as a bus or a shuttle.

[0027] Each vehicle in the fleet 100 is equipped with a temperature sensor 10 arranged to measure an outside temperature T_mes.

[0028] Indeed, the outside temperature information is generally transmitted via a sensor, the location of which varies depending on the type of vehicle. The temperature sensor may, for example, be located: - at the level of a front passenger exterior mirror, - or on the front of the vehicle, for example in an air intake upstream of a cooling exchanger, or on the bumper in the immediate vicinity of such an air intake.

[0029] In the remainder of this document, the term "outside temperature" is used to refer to the temperature of the outside air surrounding a motor vehicle. Furthermore, the term "outside temperature measurement" refers to a measurement, by the temperature sensor 10, of a temperature T_mes of the outside air surrounding the motor vehicle.

[0030] In the first embodiment, a centralized evaluation system 70 - collects observational data recorded by each vehicle 101, 102, 103 of fleet 100, each observational data point including an outside temperature measurement, - then uses observational data to assess the accuracy of measured temperatures, notably by comparing each outdoor temperature measurement to a reference temperature provided by a weather service delivery system 200.

[0031] In the remainder of the document, - the centralized assessment system 70 can be called "system 70" or "centralized system 70", or "centralized server 70" and - the local processing system 60 can be named "system 60" or "local system 60".

[0032] Each vehicle in the fleet 100 is further equipped with a means of communication 50 with the centralized server 70.

[0033] Each vehicle in the fleet 100 further includes a local evaluation device 60 with an accuracy of the monitoring system 30 of the cooling system 20.

[0034] In a second embodiment, the device 80 could include the local processing systems 60 of each vehicle in the fleet 100, without including a centralized system 70. In the second embodiment, the processing of observation data would be carried out locally in each vehicle in the fleet 100. For this purpose, the local processing system 60 of each vehicle in the fleet 100 would communicate with a meteorological service provision system 200 in order to compare each measurement of outside temperature to a reference temperature.

[0035] The invention further relates to a device 90 for improving the accuracy of an outside temperature measurement, comprising a device 80 for evaluating accuracy. The device 90 successively implements the following processes: - an evaluation of the accuracy of outside temperature measurements implemented by the device 80, - then, the detection of a substantially constant difference between an outside temperature measured by the vehicle and a reference temperature provided by a meteorological service provision system, - then, if a substantially constant difference is detected, a systematic correction of the measured temperatures according to the substantially constant difference detected.

[0036] As previously described, the first processing operation relating to the evaluation of the accuracy of measurements of an outside temperature can either be implemented locally in each vehicle of the fleet or be partially centralized in a centralized system 70. In one embodiment of the device 90, the processing operations of detection of a substantially constant deviation and systematic correction could also be implemented locally in each vehicle of the fleet.

[0037] Alternatively, the detection processes for a substantially constant deviation and systematic correction could be implemented in a centralized system 70 communicating with each vehicle in the fleet 100. This embodiment would advantageously allow processing of deviations observed over an entire fleet of vehicles to deduce a systemic drift of the sensor 10 in a given driving situation.

[0038] Thus, different modes of implementation of an architecture of the evaluation device 80 and the improvement device 90 are conceivable, depending on the choice of distribution of the processing carried out by each device, depending on whether a processing is implemented in each vehicle or in a centralized server.

[0039] In the remainder of the document, the first embodiment of the device 80 is described more specifically, in which the processing of observation data to evaluate the accuracy of the measured temperatures is carried out in the centralized server 70. Similarly, an embodiment of the device 90 is described in which the steps of detecting a deviation and systematically correcting a deviation are carried out in the centralized server 70.

[0040] The local processing system 60 of each vehicle 101, 102, 103 of the fleet 100 includes a memory 61 for recording observation data collected by the processing device 60. The observation data includes, for each measurement: - a date and time DH_mes measurement of an outside temperature, which can be provided by a clock on board the vehicle, - the outside temperature T_mes measured by a temperature sensor 10 fitted to the motor vehicle 101, 102, 103, - a geographical position POS_mes of the motor vehicle 101, 102, 103 at the date and time of measurement DH_mes, the position POS_mes being determined by a geolocation system 20 of the motor vehicle 101, 102, 103.

[0041] The date and time DH_mes and the geographical position POS_mes can be transmitted by the evaluation device 80 to a meteorological service provision system 200, the system 200 then transmitting in return a so-called reference temperature T_ref, measured at the date and time DH_mes and the geographical position POS_mes.

[0042] There is a first type of situation in which it is normal to observe a significant difference between the temperature T_mes measured by sensor 10 and a temperature T_ref from the meteorological service provision system 200. In particular, a first type of situation concerns situations in which The vehicle is located in a garage, covered parking lot, or tunnel. When an outside temperature measurement is taken while the vehicle is in such a situation, the air temperature surrounding the vehicle (measured in the garage, covered parking lot, or tunnel) may be completely different from a reference temperature provided by the Meteorological Services Provisioning System 200, as the reference temperature is measured outdoors and not inside the garage, covered parking lot, or tunnel. Therefore, temperature measurements taken while the vehicle is in such a situation must be excluded from the evaluation.

[0043] Furthermore, there is a second type of situation in which it is normal to observe a relatively large difference between a measurement T_mes from sensor 10 and a reference temperature T_ref. This second type of situation includes, in particular, a situation where the vehicle is parked in the sun. In this case, a first tolerance threshold SI will be applied to determine whether the difference between the measurement and the reference temperature corresponds to the desired accuracy; the first SI threshold could be, for example, 4 degrees Celsius.

[0044] When the vehicle is neither in a situation of the first type nor in a situation of the second type, a second tolerance threshold S2, lower than the first threshold SI, will be applied to determine whether the difference between the measurement and the reference temperature corresponds to the desired accuracy, the second threshold S2 being for example 2 degrees Celsius.

[0045] In order to be able to detect whether the vehicle is in one of the first or second types of situations, the observation data collected by the processing device 60 advantageously includes an observation of the following data at the date and time of measurement: - a vehicle ST_mes state defined as one of the following states: parked with engine off, parked with engine running, or in motion, and / or - a level of sunlight ENS_mes measured by a sunlight sensor 30 on the vehicle, and / or - a longitudinal speed VL_mes of the vehicle.

[0046] In one embodiment, the sunlight sensor 30 is located on the front windshield of the motor vehicle. Situations of the first type can be detected by comparing the sunlight level measured by the sensor 30 to a maximum threshold; the time of day can also be taken into account in the detection of a situation of the first type.

[0047] In addition, the level of sunlight ENS_mes and / or the longitudinal speed VL_mes of the vehicle can be used to detect a situation of the second type.

[0048] The invention further relates to a device 95 for improving the accuracy of an external air temperature measurement T_ext of a fleet 100 of vehicles. The device 95 interacts with a fleet of vehicles to improve the accuracy of temperature measurements on all vehicles in the fleet 100.

[0049] An embodiment of a method for evaluating the accuracy of an external temperature measurement of a motor vehicle 101, 102, 103 is described below with reference to [Fig.1].

[0050] In a first step E10, an observation OBS data point is collected, the observation OBS data point comprising: - a date and time DH_mes of measurement of an outside temperature T_mes, - an outside temperature T_mes measured by a temperature sensor 10 fitted to the motor vehicle 101, 102, 103, - a geographical position POS of the motor vehicle 101, 102, 103 at the date and time of measurement, determined by a geolocation system 20 of the motor vehicle 101, 102, 103, and optionally: - a vehicle ST_mes state defined as one of the following states: parked with engine off, parked with engine running, or in motion, and / or - a level of sunlight ENS_mes measured by the vehicle's sunlight sensor 30, and / or - a longitudinal speed VL_mes of the vehicle.

[0051] The vehicle state ST_mes and the longitudinal speed VL_mes can be determined from data from a navigation software and / or from data from an internal data network of the motor vehicle 101, 102, 103.

[0052] The observation data is then recorded in a local memory 61 of the motor vehicle.

[0053] In one embodiment, the E10 collection step is executed periodically, the iteration period being able to depend on the driving phase of the motor vehicle 101, 102, 103.

[0054] In addition, or alternatively, observational data are collected at times determined by the needs of the vehicle's equipment. For example, observational data can be measured when a user starts the cabin air conditioning.

[0055] According to one execution mode, the first data acquisition step E10 is iterated several times before proceeding to a second step E20 for acquiring a reference temperature. In an alternative execution mode, following the first step E10, the second step E20 could be performed directly.

[0056] In the embodiment described below, the collection step E10 includes a substep of transmitting observation data collected during step E10 to the centralized server 70 and the acquisition steps E20, comparison E30, and determination E35 are executed by a centralized system 70 communicating with the motor vehicle 101, 102, 103, and the method includes a reception by the centralized system 70 of observation data transmitted by the motor vehicle 101, 102, 103.

[0057] In step E20, for each OBS observation data collected during step E10, a reference temperature T_ref is acquired provided by a meteorological service provision system 200, the reference temperature T_ref being determined according to the geographical position POS_mes of the observation data and according to the date and time DH_mes of the OBS observation data.

[0058] Thus, in the described embodiment, step E20 includes sending a request from the centralized server 70 to a meteorological service provision system 200. The request contains information relating to the date, time and position of a temperature measurement taken by the sensor 10. The meteorological service provision system 200 transmits in response a reference temperature T_ref corresponding to the date, time and position which were transmitted to it by the centralized server.

[0059] Then, following the receipt of a reference temperature T_ref for each observation data OBS, we proceed to step E30 of comparison of a difference between the outside temperature T_mes of the observation data OBS and the reference temperature T_ref with a given threshold SI, S2.

[0060] Thus, in one embodiment, the accuracy of an outside temperature measurement by the motor vehicle is determined by a difference DT between the measured temperature and a reference temperature T_ref provided by the meteorological service provision system 200.

[0061] For this purpose, it is checked whether, at the time of the temperature measurement, the vehicle was in a particular situation likely to generate a significant difference between the temperature of an outside air measured by the vehicle and the reference temperature provided by the meteorological service provision system 200.

[0062] Thus, in step E30, it is first verified whether, at time T_mes when the measurement was taken, the vehicle was in the first type of situation. To do this, it is verified that the level of sunlight ENS_mes measured at time T_mes by a sunlight sensor 30 on the vehicle is greater than a first sunlight threshold. Advantageously, the first sunlight threshold is defined to allow the detection of observational data such as, at time T_mes of measurement of the temperature, the vehicle was in a dark space isolated from outside air, for example in a parking lot, garage or tunnel.

[0063] Thus, if the level of sunshine is below the first sunshine threshold, the observation data will not be taken into account in the evaluation of the reliability of a temperature measurement.

[0064] Then, in a second step, it is verified whether, at the time T_mes when the measurement was taken, the vehicle was in the second type of situation, that is, whether the vehicle was stationary and in the sun. To do this, it is verified whether the longitudinal speed of the vehicle is zero and whether the level of sunlight ENS_mes is greater than a second sunlight threshold. Advantageously, the second sunlight threshold corresponds to a significant level of sunlight.

[0065] Thus, if the level of sunlight is above the second sunlight threshold, and if the longitudinal speed of the vehicle is zero, then it is determined that at the time of the temperature measurement, the vehicle was in a situation of the second type. To assess the reliability of the measurement, it is verified that an absolute value of the difference between the measured temperature T_mes and the reference temperature T_ref is less than or equal to a first SI threshold, the first SI threshold being, for example, 4 degrees.

[0066] If, at the time of measurement of the temperature T_mes, the vehicle was neither in a situation of the first type, nor in a situation of the second type then it is verified that an absolute value of a difference between the temperature measurement T_mes and the reference temperature T_ref is less than or equal to a second threshold S2, the second threshold S2 being advantageously less than the first threshold SI, the second threshold S2 being able to be equal, for example, to 2 degrees.

[0067] Thus, the comparison step E30 allows for the implementation of a step E35 for determining the accuracy of a temperature measurement, comprising • when the vehicle is in a situation of the first type at the time of measurement DH_mes, a determination of the accuracy of a temperature measurement as being indefinite, • when the vehicle is in a situation of the second type at the time of measurement DH_mes, a determination of the accuracy of the temperature measurement as being (i) of a first level of accuracy if an absolute value of a difference between the measured temperature (T_mes) and the reference temperature (T_ref) is less than or equal to a first threshold (SI), in particular less than or equal to 4 degrees, (ii) otherwise, of an insufficient level of accuracy, • otherwise, a determination of the accuracy of the temperature measurement as being (i) a second level of precision if an absolute value of a difference between the measured temperature (T_mes) and the reference temperature (T_ref) is less than or equal to a second threshold (S2), in particular less than or equal to 2 degrees, (ii) otherwise, an insufficient level of precision, the first threshold (SI) being greater than or equal to the second threshold (S2).

[0068] An embodiment of a first method for improving the accuracy of an outside temperature measurement of a motor vehicle 101, 102, 103, is described below with reference to [Fig.3].

[0069] The improvement process according to the invention comprises an evaluation step E40 including the previously described steps E10, E20, E30, and E35. Following step E35, the accuracy of a measurement of the outside air temperature of a motor vehicle was determined. Advantageously, step E40 includes an iteration of steps E10, E20, E30, and E35, thus allowing for several determinations of the accuracy of an outside temperature measurement for a given vehicle.

[0070] When the accuracy of the temperature measurements is determined to be insufficient in step E40, an analysis can be carried out on the temperature measurement accuracies determined for a given vehicle. The analysis includes a detection step E50 of a substantially constant deviation DT, on the various observation data recorded by the motor vehicle, between a temperature measured by the vehicle and a reference temperature provided by a meteorological service provision system.

[0071] Then, if a substantially constant difference is detected, we proceed to step E60 of systematic correction of the temperatures measured by the vehicle according to the substantially constant difference DT detected.

[0072] A correction is said to be systematic when it consists, for a given vehicle, of applying the same corrective treatment to each measured temperature. For example, a systematic correction could be an increase or decrease of a given number of degrees Celsius in each temperature measured by the vehicle.

[0073] In one embodiment, steps E40, E50, and E60 are executed locally in each vehicle. Alternatively, steps E40, E50, and E60 may be partially executed in a centralized server 70 communicating with each of the vehicles; in particular, steps E50 and E60 may be executed in the centralized server 70. The systematic correction step E60 then includes transmitting to each vehicle a systematic correction to be applied by the vehicle to the measured temperatures. The systematic correction may vary from one vehicle to another.

[0074] Thus, in the event of a drift in the measurement of the outside temperature, the steps of the process executed in the centralized server 70 could make it possible to correct directly into each vehicle, via "Firmware over-the-air" (FOTA) technology, embedded software for vehicle systems consumes outside temperature information. Corrections to this embedded software could include, for example, applying a systematic correction to the measured outside temperature.

[0075] An embodiment of a second method for improving the accuracy of an outside temperature measurement of a set of 100 motor vehicles is described below with reference to [Fig. 4]. The improvement method then relates to an entire fleet of 100 vehicles: it consists of applying a systematic correction to all outside temperature measurements taken by the fleet of vehicles.

[0076] To this end, the second method comprises, - a step E70 for evaluating the accuracy of an external air temperature measurement T_ext, comprising the steps E10, E20, E30 and E35 previously described, applied to each vehicle in assembly 100, - a step E80 of detecting a substantially constant difference, on the different observation data recorded by the vehicles of the set 100, between a temperature measured by a vehicle of the set 100 and a reference temperature T_ref provided by a meteorological service provision system 200, - then, if a substantially constant difference is detected, a step E90 of systematic correction, by the vehicles of the set, of the temperatures measured according to the substantially constant difference detected.

[0077] Finally, the methods and devices according to the invention make it possible to improve the accuracy of an outside temperature measured by a sensor installed on a motor vehicle or each vehicle in a fleet of motor vehicles. The so-called reference data provided by a weather service delivery system do not replace measurements taken by the sensors installed on each vehicle. On the contrary, the reference data are used to verify the validity of the measurements taken by the sensor installed in each vehicle, and to detect significant discrepancies between the reference data and the sensor measurements.

[0078] The method for evaluating the accuracy of a temperature measurement is thus based on calculating the difference between a temperature measured by the temperature sensor onboard the vehicle and a reference temperature provided by meteorological services. A tolerance threshold is applied to this difference, which may vary depending on the driving conditions under which the measurements were taken by the onboard sensor. To this end, the method according to the invention includes identifying specific driving conditions that could distort the measurement, for example, a temperature measurement by the sensor while the vehicle is parked in the sun. When a driving condition is specific, the measurement is not not taken into account, or its accuracy is tested according to a more flexible evaluation criterion.

[0079] The invention further relates to a method and device for improving the accuracy of an external temperature measurement of a motor vehicle, enabling the systematic application of a correction to all measurements from a sensor of a given vehicle when a substantially constant error is detected in the temperature measurements from the sensor. Thanks to this method, the temperature measurements taken by the sensor of the vehicle in question can be corrected remotely without the need for physical intervention on the vehicle.

[0080] Similarly, the invention further relates to a method and device for improving the accuracy of an outside temperature measurement for a fleet of motor vehicles. This method advantageously allows for addressing discrepancies observed across an entire fleet of vehicles in order to detect and correct systemic drift in the temperature sensor, possibly within a given driving situation.

Claims

Demands

1. A method for evaluating the accuracy of a measurement (T_mes) of the temperature of the outside air of a motor vehicle (101, 102, 103), comprising • a step (E10) of collecting observational data (OBS) comprising o a date and time (DH_mes) of measurement of an outside temperature (T_mes), o a temperature (T_mes) measured by a temperature sensor (10) fitted to the motor vehicle (101, 102, 103), o a geographical position (POS_mes) of the motor vehicle (101, 102, 103) at the date and time of measurement (DH_mes), determined by a geolocation system (20) of the motor vehicle (101, 102, 103), • a step (E20) of acquiring a reference temperature (T_ref) provided by a meteorological service delivery system (200), the reference temperature (T_ref) being determined according to the geographical position (POS_mes) of the observation data (OBS) and according to the date and time (DH_mes) of the observation data (OBS), • then, a step (E30) of comparing a difference between the temperature (T_mes) of the observation data (OBS) and the reference temperature (T_ref) at a predefined threshold (SI, S2), each observation data point (OBS) of the motor vehicle (101, 102, 103) including further - a vehicle state defined as being parked with the engine off (ST1), parked with the engine running (ST2), or in motion (ST3), and / or - a level of sunlight (ENS) measured by a sunlight sensor (30) on the vehicle, and / or - a longitudinal speed (VL) of the motor vehicle (101, 102, 103), the comparison step (E30) comprising detection, based on the vehicle's condition and / or the level of sunlight and / or the longitudinal speed and / or the vehicle's location, of a vehicle situation of type 1, in which the vehicle is located in a dark space, particularly in a garage, covered parking lot, or tunnel, and of a vehicle situation of type 2, in which the vehicle is parked in the sun, the method further comprising a step (E35) for determining the accuracy of a temperature measurement, including • when the vehicle is in a situation of the first type at the time of measurement (DH_mes), a determination of the accuracy of a temperature measurement as being indefinite, • when the vehicle is in a situation of the second type at the time of measurement (DH_mes), a determination of the accuracy of the temperature measurement as being • a first level of precision if an absolute value of a difference between the measured temperature (T_mes) and the reference temperature (T_ref) is less than or equal to a first threshold (SI), in particular less than or equal to 4 degrees, • otherwise, of an insufficient level of precision, • otherwise, a determination of the accuracy of the temperature measurement as being • a second level of precision if an absolute value of a difference between the measured temperature (T_mes) and the reference temperature (T_ref) is less than or equal to a second threshold (S2), in particular less than or equal to 2 degrees, • otherwise, of an insufficient level of precision, the first threshold (SI) being greater than or equal to the second threshold (S2).

2. Evaluation method according to the preceding claim, characterized in that the acquisition (E20), comparison (E30) and stages of determination (E35) are performed by a centralized system (70) communicating with the motor vehicle (101, 102, 103), and in that the method includes a reception by the centralized system (70) of observation data transmitted by the motor vehicle (101, 102, 103).

3. A method for improving the accuracy of an outside temperature measurement of a motor vehicle (101, 102, 103), comprising: - a step (E40) of evaluating the accuracy of a measurement (T_mes) of an outside air temperature (T_ext) according to one of the preceding claims; - a step (E50) of detecting a substantially constant deviation (DT) on the different observation data recorded by the motor vehicle, between an outside air temperature (T_mes) measured by the vehicle and a reference temperature (T_ref) provided by a meteorological service provision system (200); - then, if a substantially constant deviation is detected, a step (E60) of systematically correcting the outside air temperatures measured by the vehicle according to the substantially constant deviation detected.

4. Improvement method according to the preceding claim, comprising acquisition (E20), comparison (E30) and determination (E35) steps performed by a centralized system (70) communicating with the motor vehicle (101, 102, 103), characterized in that it is performed by a centralized system (70) communicating with the motor vehicle (101, 102, 103), and in that the systematic correction step (E60) comprises a transmission to the motor vehicle of a systematic correction to be applied by the motor vehicle (101, 102, 103) to the measured temperatures.

5. Method for improving the accuracy of a measurement (T_mes) of an outside temperature of a set (100) of motor vehicles (101, 102, 103), comprising, - a step (E70) of evaluating the accuracy of a measurement (T_mes) of an outside air temperature (T_ext) according to one of claims 1 or 2, applied to each vehicle of the set (100), - a step (E80) of detecting a substantially constant deviation (DT) on the different observation data recorded by the vehicles of the set (100), between a temperature (T_mes) measured by a vehicle of the set (100) and a reference temperature (T_ref) provided by a meteorological service provision system (200), - then, if a substantially constant deviation (DT) is detected, a step (E90) of systematic correction, by the vehicles of the set (100), of the temperatures measured according to the substantially constant deviation (DT) detected.

6. Motor vehicle (101, 102, 103) characterized in that it comprises the hardware () and software means for implementing the steps of the evaluation process according to any one of claims 1 or 2 and / or the steps of a process for improving the accuracy of an outside temperature measurement of a motor vehicle according to any one of claims 3 or 4, and / or the steps of a process for improving the accuracy of an outside temperature measurement of a set (100) of motor vehicles according to claim 5.

7. Device (80) for evaluating the accuracy of a measurement of an outside air temperature (T_ext) of a motor vehicle, the device comprising hardware and / or software elements (10, 20, 30, 40, 50, 60, 61, 70, 100, 101, 102, 103) implementing the method according to one of claims 1 or 2.

8. Device (90) for improving the accuracy of a measurement of an outside air temperature (T_ext) of a motor vehicle, the device comprising hardware and / or software elements (10, 20, 30, 40, 50, 60, 61, 70, 80, 100, 101, 102, 103) implementing the method according to one of claims 3 or 4.

9. Device (95) for improving the accuracy of a measurement of an outside air temperature (T_ext) of a vehicle assembly (100), the device comprising hardware and / or software elements (10, 20, 30, 40, 50, 60, 61, 70, 80, 90, 100, 101, 102, 103) implementing the method according to claim 5.

Images