EP-4735848-A1 - METHOD FOR ESTIMATING THE VEHICLE-DISTRIBUTED LOAD RESULTING FROM THE PASSENGER IN THE VEHICLE

EP4735848A1EP 4735848 A1EP4735848 A1EP 4735848A1EP-4735848-A1

Abstract

Disclosed is a method for estimating the variation in the load of a mounted assembly on a vehicle, the variation being the result of a passenger boarding the vehicle, the method comprising the following steps: ♦ having the passenger board the vehicle; ♦ recording the internal temperature T in the fluidic cavity of an equipped mounted assembly; ♦ ascertaining the internal pressure P in the fluidic cavity of the equipped mounted assembly using a specified law of change; ♦ evaluating a variation in the volume ΔV of the equipped mounted assembly by means of the recorded internal temperature T and the ascertained internal pressure P using a model of a fluid in adiabatic transformation, the fluid having a perfect gas behavior; and ♦ estimating a variation in the load ΔZ carried by the n equipped mounted assembly using a second function comprising, as a parameter, the evaluated intermediate variation in volume ΔV and the flattening stiffness of the tire of the mounted assembly per unit volume K p .

Inventors

QUADRINI, MATTHIEU
MARTIN, DENIS
PERNOT, Alexandre
BERLIOUX, LOIC

Assignees

COMPAGNIE GENERALE DES ETABLISSEMENTS MICHELIN

Dates

Publication Date: 20260506
Application Date: 20240625

Claims (20)

1. Method for estimating the variation in load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle comprising the following steps: In the preliminary phase, - Equip each mounted assembly of the vehicle with at least one temperature sensor, said sensor being capable of measuring the internal temperature of the fluid cavity of the mounted assembly delimited by a pneumatic envelope and a wheel; - Determine the initial load ZI applied to each assembly fitted to the vehicle; - Determine the initial inflation pressure PI of the fluid cavity of each assembly fitted to the vehicle; - Determine the initial internal temperature Tl of the fluid cavity of each assembled assembly equipped with the vehicle; - Evaluate the initial volume VI of each assembled assembly equipped using a first function comprising as parameter the volume VO of the fluid cavity of the assembled assembly unloaded and inflated to the initial pressure PI and the flattening rigidity of the tire of the assembled assembly per unit of volume Kp, - Evaluate the number of moles of fluid n in the fluid cavity of each assembled assembly equipped from a model taking into account the inflation pressure PI, the initial volume VI, the temperature Tl; - Determine a law of evolution of the internal pressure P of the fluidic cavity from the internal temperature T during an adiabatic transformation for each assembly mounted, inflated and subjected to the load Zl, equipped with at least one temperature sensor; In the main phase: - Position at least one passenger in the vehicle; - Record the internal temperature T in the fluid cavity of each equipped assembly at an acquisition frequency Fl; - Determine the internal pressure P of the fluid cavity of at least one equipped assembly using the evolution law determined in the preliminary phase; - Evaluate an intermediate AV volume variation of each equipped assembly using the recorded internal temperature T and the internal pressure P determined at using a fluid model in adiabatic transformation, the fluid having ideal gas behavior; and - Estimate a load variation AZ carried by each mounted assembly equipped using a second function comprising as parameter the intermediate AV volume variation evaluated and the flattening rigidity of the tire of the mounted assembly per unit of volume Kp.
2. Method for estimating the variation in the load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle according to claim 1 in which, in the preliminary phase, the at least one mounted assembly equipped with the at least one axle of the vehicle comprising a pressure sensor capable of measuring the internal pressure of the fluid cavity, the method comprises, in the main phase, a step for recording the internal pressure P of the fluid cavity of the at least one mounted assembly equipped when at least the internal temperature T recorded changes direction of variation or after a duration TO corresponding to the end of the adiabatic transformation of the fluid and the method comprises a second step of evaluating the variation in intermediate volume AV2 of the at least one mounted assembly equipped taking into account the internal pressure P recorded, the internal temperature T recorded corresponds to the period of recording the internal pressure P using a fluid model in adiabatic transformation, the fluid having ideal gas behavior.
3. Method for estimating the load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle according to one of claims 1 to 2 in which, before the main step, each equipped mounted assembly is in a thermomechanically stabilized state.
4. Method for estimating the variation in the load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle according to one of claims 1 to 3 in which the temperature sensor and/or the pressure sensor are placed in a subspace of the closed fluid cavity delimited by the pneumatic casing and the wheel.
5. Method for estimating the variation in the load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle according to one of claims 1 to 4 in which the acquisition frequency Fl is between 0.1 Hz and 10 Hz.
6. Method for estimating the variation in the load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle according to one of claims 1 to 5 in which the determination of the initial volume V0 takes into account the geometry of a wheel rim and the geometry of an unloaded tire, mounted on a rim and inflated to a reference pressure PO, preferably the reference pressure PO is the initial pressure PI.
7. Method for estimating the variation in the load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle according to claim 6 in which the geometry of the tire and/or the geometry of the rim is determined using an identifier of the tire and/or the wheel of the equipped mounted assembly, preferably obtaining the identifier of said tire and/or said wheel is carried out by a radiofrequency interrogation of an electronic device located on the mounted assembly.
8. Method for estimating the variation in the load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle according to one of claims 1 to 7 in which the load Z of each equipped mounted assembly is estimated by a relationship according to the following formula: Z = K PP * P * A(F) = Kpp * P * (Fl - FO [MATH1] where Kpp is the flat tire rigidity of the assembled tire per unit volume.
9. Method for estimating the variation in load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle according to one of claims 1 to 8 in which the variation in AV volume of each equipped mounted assembly is estimated by solving the following differential equation: [MATH 2] , and with [MATH 3] , where P is the internal pressure, V is the internal volume and T is the internal temperature of the fluid cavity.
10. Method for estimating the number and location of passengers in a vehicle comprising the method for estimating the variation in load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle according to one of claims 1 to 9 in which, having determined a track value and a wheelbase value of the vehicle, as well as an average support point of a passenger on each seat of the vehicle, the method comprises the following steps; - Determination of the total load P generated by at least one passenger by adding together the load variations AZ carried by each mounted assembly equipped with the vehicle; - Determination of a center of gravity G of the total load P generated by the at least one passenger and obtaining the coordinates of the center of gravity G in a reference point R associated with the vehicle; - Determination of an average number of passengers N as the ratio between the total load Z generated by the at least one passenger and a reference number REF, preferably the reference number REF represents the average weight of an adult; Identification of the combinations of location on each seat of the vehicle and type of passenger respecting the average number of passengers N; - Determination of the coordinates of a center of gravity J of all passengers for each identified combination of passengers in the reference frame R; and Identification of the best possible identified combination minimizing the distance between the center of gravity G and the center of gravity J.
11. A method of estimating the number and location of passengers in a vehicle according to claim 10, in which the type of passenger is included in the group comprising an adult male, an adult female, an adolescent and a child.
12. System (2000) for implementing the method (1000) for estimating the variation in load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle according to one of claims 1 to 9 and or for implementing implementation of the method for estimating the number and location of passengers in a vehicle according to one of claims 10 to 11 comprising: - a vehicle (2001) capable of accommodating at least one passenger on a seat, each mounted assembly (2006) of which is equipped with an electronic device (2007); the electronic device (2007) comprising at least one temperature sensor, at least one electronic chip, at least one memory space capable of recording the signals from the sensor, and at least one first means of radiofrequency communication (2101) at least in transmission; at least one means of calculation (2002); and at least one means of display (2003) comprising at least one second means of radiofrequency communication (2102) at least in reception.
13. System (2000) for implementing the method (1000) for estimating the variation in load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle and/or for implementing the method for estimating the number and location of passengers of a vehicle according to claim 12 in which the system (2000) comprises an analysis means (2004) capable of analyzing a result at the output of the at least one calculation means (2002).
14. System (2000) for implementing the method (1000) for estimating the variation in load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle and/or for implementing the method for estimating the number and location of passengers of a vehicle according to one of claims 12 to 13 in which the at least one calculation means (2002) comprises at least a third radiofrequency communication means (2103) in transmission/reception.
15. System (2000) for implementing the method (1000) for estimating the variation in load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle and/or for implementing the method for estimating the number and location of passengers of a vehicle according to claim 14 in which the at least one analysis means (2004) comprising at least a fourth radiofrequency communication means (2104) in transmission/reception
16. System (2000) for implementing the method (1000) for estimating the variation in load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle and/or for implementing the method for estimating the number and location of passengers of a vehicle according to one of claims 12 to 15 in which the system (2000) comprises at least one reading means (2005) capable of at least reading data contained in the at least one memory space of the electronic device (2007) comprising at least one fifth communication means (2105) at least in reception.
17. System (2000) for implementing the method (1000) for estimating the variation in load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle and/or for implementing the method for estimating the number and location of passengers of a vehicle according to one of claims 12 to 16 in which part of the communication carried out by the communication means (2101, 2102, 2103, 2104, 2105) from and to the elements included in the group comprising the electronic device (2007), the at least one calculation means (2002), the at least one display means (2003), the at least one analysis means (2004) and the at least one reading means (2005) is carried out by UHF radiofrequency waves, preferably in BLE.
18. System (2000) for implementing the method (1000) for estimating the variation in load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle and/or for implementing the method for estimating the number and location of passengers in a vehicle according to one of claims 12 to 17 in which the at least one display means (2003) is included in the group comprising a telephone, a computer, a human-machine interface located on the vehicle (2001), preferably located on the instrument cluster of the vehicle (2001).
19. System (2000) for implementing the method (1000) for estimating the variation in load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle and/or for implementing the method for estimating the number and location of passengers of a vehicle according to one of claims 12 to 18 in which a part of the at least one reading means (2005) is located on the vehicle (2001).
20. System (2000) for implementing the method (1000) for estimating the variation in load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle and/or for implementing the method for estimating the number and location of passengers of a vehicle according to one of claims 12 to 19 in which a part of the at least one calculation means (2002) and/or a part of the at least one analysis means (2004) is located on the vehicle (2001), preferably located on the mounted assembly (2006).

Description

DESCRIPTION TITLE: METHOD FOR ESTIMATING THE LOAD DISTRIBUTED ON A VEHICLE DUE TO THE VEHICLE PASSENGER Field of invention [0001] The present invention relates to the field of real-time determination of the load variation generated by the boarding of passengers in the vehicle, in particular when the vehicle is stationary, making it possible to identify the number of passengers boarded and their location in the passenger compartment of the vehicle. Technological background [0002] Obtaining the variation in static load applied to a stationary vehicle makes it possible to determine the presence of people on board the vehicle. Indeed, determining the variation in load applied to inflatable systems such as mounted assemblies generally requires a balancing scale; it is not easy to determine this load outside of very specific loading locations. In order to evaluate the variation in load carried by the vehicle outside of these specific locations, it is possible to evaluate the load carried by each mounted assembly of the vehicle by indicating the footprint of the tire on the ground. Although a measurement using a static pressure quantification system is possible by inserting the measurement system between the mounted assembly and the ground, its implementation is not simple and the accuracy of the measurement is subject to the correct positioning of the measurement system. Another alternative is to evaluate the size of the contact area in rolling conditions by measuring the deformation of the tire around the wheel in order to determine the size of the contact area. Through a mathematical model, linking the type of tire, the inflation pressure and the external dimension of the footprint, we then go back to the variation of load applied to the tire casing. Unfortunately, this measurement is in rolling conditions. In addition, the precision of these measurements is delicate for very heavy loads where the deformation of the tire which determines the load variations tends to stabilize according to the circumferential direction on which the evolution of the measurement of the deformation of the tire casing generally relates. As a result, we cannot determine the number of passengers or their location in the vehicle before taking to the road. In conclusion, we cannot check that the seat belts of each person are properly fastened passenger or to adapt the belt restraint force to the type of passenger seated, i.e. an adult or a child for example. [0003] The objects and methods of the invention which follow aim to solve the problem of measuring the variation in load carried by the vehicle when passengers board the vehicle in the absence of a measuring system external to the vehicle, i.e. usable at any time without specific measuring means. In addition, this evaluation is carried out while the vehicle is stationary, making it possible to decide on the number of passengers and their location in the vehicle before any movement thereof. Description of the invention [0004] The invention relates to a method for estimating the variation in load carried by a mounted assembly of a vehicle generated by the boarding of at least one passenger in the stationary vehicle comprising the following steps: • In the preliminary phase, that is to say before boarding at least one passenger in the vehicle, • Equip each mounted assembly of the vehicle with at least one temperature sensor, said sensor being capable of measuring the internal temperature of the fluid cavity of the mounted assembly delimited by a pneumatic casing and a wheel; • Determine the initial load ZI applied to at least one mounted assembly equipped with the vehicle; • Determine the initial inflation pressure PI of at least one mounted assembly equipped with the vehicle; • Determine the initial internal temperature Tl of at least one mounted assembly equipped with the vehicle; • Evaluate the initial volume VI of each assembled assembly equipped at T using a first function comprising as parameter the volume V0 of the fluid cavity of the assembled assembly unloaded and inflated to the initial pressure PI and the flattening rigidity of the tire of the assembled assembly per unit of volume Kp • Evaluate the number of moles of fluid n in the fluid cavity of each assembled assembly equipped from a model taking into account the inflation pressure PI, the initial volume VI, the temperature Tl; • Determine a law of evolution of the internal pressure P of the fluid cavity from the internal temperature T during an adiabatic transformation for the at least one assembled assembly, inflated and subjected to the load Zl, equipped with at least one pressure sensor; • In the main phase, • Position at least one passenger in the vehicle; • Record the internal temperature T at the fluid cavity of each assembled assembly equipped at an acquisition frequency Fl; • Determine the internal pressure P of the fluid cavity of each equipped assembly using the evolution law determined in the preliminary pha