Abstract: A method for the hands-free access to a motor vehicle (V) is combined with a method for monitoring tire pressure. More particularly, wheel units (20, 21, 22, 23) belonging to the tire pressure recognition system detect the cessation of low frequency LF transmissions caused by the recognition of a badge B paired with the vehicle in order to trigger the measurement via the wheel units of the pressure and temperature values prevailing in each tire of the vehicle. These pressure and temperature measurements are sent to a central unit (14), which is mounted on the vehicle, so as to provide the driver with this information. The temperature and pressure measurements are transmitted to the central unit as soon as the measurements have been taken, irrespective of whether or not the driver has entered the vehicle.

Abstract: A method for self-calibrating, while a vehicle is moving, an accelerometer mounted on a wheel of the vehicle so that its plane of maximum sensitivity is secant with the axis of rotation of the wheel. The average value and on the other hand the amplitude of the signal representative of the acceleration Acc-read delivered by the accelerometer are calculated first, for an established speed of the vehicle, based on measurements performed by the accelerometer during a time window corresponding to the time needed for the wheel to complete n rotations, with n>1, then the values of the gain C1 and of the offset C2 of the accelerometer are determined by resolving the system of two equations with two unknown values: ?2R=C1×(average value of Acc-read)+C2 2 g=C1×(amplitude of Acc-read) with: ? the speed of rotation of the wheel, R the radius of the wheel.

Abstract: In a system for monitoring the pressure of the tires of a vehicle, it is proposed to compensate the raw data of the parameters of the tires only if the comparison of the successive raw data of at least one reference parameter exhibits a deviation, in absolute value, greater than a determined threshold of variation. In a TPMS monitoring system, each wheel unit includes sensors for measuring the parameters of pressure, temperature and acceleration, and elements of storage and autonomous power supply, in conjunction with a processor. The raw data provided by the sensors are stored, compensated and transmitted as finalized data by a radiofrequency emission circuit to a central unit. It is proposed that the wheel unit also includes, in a processing module, comparison elements, external to the processor, for comparing between successive raw data of one and the same parameter that are provided by the measurement sensors.

Abstract: A method (2) for detecting the malfunctioning of a sensor (11) of the pressure of a gas inside a tire of a vehicle includes at least a step (20) of determining whether a predefined gas temperature variation detection criterion is verified. If a temperature variation is detected, the method (2) includes a step (21) of determining whether a predefined criterion for detection of the variation of the pressure, measured by the pressure sensor (11), is verified. If a pressure variation is not detected, the method (2) includes a step (22) of notifying that a malfunction of the pressure sensor (11) has been detected. A device for detecting the malfunctioning of a sensor (11) of the pressure of a gas inside a tire of a vehicle is also described.

Abstract: A device (20) for charging a portable element (10) having a receiving antenna (Ar) for charging by induction, the charging device (20) includes: a charging surface (Sc); a plurality of emitting antennas (A1, A3); a layer of ferromagnetic material (30) placed beneath the plurality of emitting antennas (A1, A3); an electronic circuit; a plurality of resonators (R1, R2 . . . Ri): having a resonance frequency substantially equal to the emission frequency of the antennas, placed between the plurality of antennas and the charging surface, and suitable, when they are activated, for reflecting the magnetic field (B) emitted by the antennas, and connected to the electronic circuit in order to be deactivated individually, according to a criterion of positioning of the receiving antenna relative to the resonators.

Abstract: A method for determining a pivoting angle (?) of a wheel unit (12) mounted onto a snap-in inflation valve (10) includes the following three phases: observation of a curve representing the effect of gravity on the radial acceleration Ames of a wheel of the vehicle on a sensing axis Y? which is related to the wheel unit and is not parallel to the axis of rotation of the wheel, by spectrum analysis of the gravity curve at a sampling frequency Fs greater than an assumed rotation speed ? of the wheel, deduction of the actual rotation speed ? of the wheel, and determination of the pivoting angle ? according to the formula cos ? ? ? = A mes _ ? 2 ? × R , where ? is the actual angular speed deduced from the observation of the curve, Ames is a mean value of the corrected radial acceleration, and R is a standardized radius of the wheel.

Abstract: A charging bench includes three coils that partially overlap, in superposed planes. An electrical feed makes it possible to supply the coils with an AC current from the mains. A portable device to be charged is placed on the upper side of this charging bench. This device includes a winding intended to receive the electrical charging, and a ferrite protective screen. One of the coils (Bb) is selected to emit the magnetic charging flux toward the mobile phone. The selection is carried out via the emission of a series of pulses by at least one of the coils and comparison of return signals with a reference threshold. This comparison also enables one of the other coils (Ba, Bc) to be selected or both of these other two coils (Ba, Bc) to be used to receive a flux for communicating information originating from the portable device to be charged.

Abstract: Method of controlling the drifting of a low-frequency LFO circuit in a wheel unit of a tire pressure monitoring system, each wheel unit including temperature and pressure sensors in conjunction with a signal control circuit, the sensors being activated according to an LFO circuit time base integrated into the control circuit. An RF emission circuit of each wheel unit transmits data stored in a memory and an identifier of the unit to a central unit. The emission circuit is regulated by a high-precision clock. In each wheel unit, a variation between a measured temperature and a reference temperature is compared with a variation threshold and a drift between the periods of the time base of the LFO circuit and of the clock is determined. The drift is used to adjust the time base to the period of the clock if the temperature variation ?Ti is greater than this threshold ?T.

Abstract: An inductive charging device (20) for a portable apparatus for an automobile vehicle including at least one charging antenna (70) for inductive charging of the WPC type having a cut-out at its center (62) together with one communication antenna (60) for near-field communication of the NFC type, situated around the at least one charging antenna, along the sides of the charging device (Z1, Z2, Z3, Z4) and including at least one winding, the device being such that: on at least one of the sides of the charging device, the communication antenna forms at least one loop (B) having at least one crossing point (61) on its base, the communication antenna having at least an upper part (63) surrounding the center of the cut-out of the charging antenna, the upper part of the loop of the communication antenna surrounding the center of the cut-out has at least one winding.

Abstract: In a system for monitoring the pressure of the tires of a vehicle, it is proposed to compensate the raw data of the parameters of the tires only if the comparison of the successive raw data of at least one reference parameter exhibits a deviation, in absolute value, greater than a determined threshold of variation. In a TPMS monitoring system, each wheel unit includes sensors for measuring the parameters of pressure, temperature and acceleration, and elements of storage and autonomous power supply, in conjunction with a processor. The raw data provided by the sensors are stored, compensated and transmitted as finalized data by a radiofrequency emission circuit to a central unit. It is proposed that the wheel unit also includes, in a processing module, comparison elements, external to the processor, for comparing between successive raw data of one and the same parameter that are provided by the measurement sensors.

Abstract: A method (2) for detecting the malfunctioning of a sensor (11) of the pressure of a gas inside a tire of a vehicle includes at least a step (20) of determining whether a predefined gas temperature variation detection criterion is verified. If a temperature variation is detected, the method (2) includes a step (21) of determining whether a predefined criterion for detection of the variation of the pressure, measured by the pressure sensor (11), is verified. If a pressure variation is not detected, the method (2) includes a step (22) of notifying that a malfunction of the pressure sensor (11) has been detected. A device for detecting the malfunctioning of a sensor (11) of the pressure of a gas inside a tire of a vehicle is also described.

Abstract: Method of controlling the drifting of a low-frequency LFO circuit in a wheel unit of a tire pressure monitoring system, each wheel unit including temperature and pressure sensors in conjunction with a signal control circuit, the sensors being activated according to an LFO circuit time base integrated into the control circuit. An RF emission circuit of each wheel unit transmits data stored in a memory and an identifier of the unit to a central unit. The emission circuit is regulated by a high-precision clock. In each wheel unit, a variation between a measured temperature and a reference temperature is compared with a variation threshold and a drift between the periods of the time base of the LFO circuit and of the clock is determined. The drift is used to adjust the time base to the period of the clock if the temperature variation ?Ti is greater than this threshold ?T.

Abstract: A method of detecting the motion of a vehicle (13) of which at least one wheel unit (11) of said vehicle is equipped with a motion detection element (D) that generates a motion signal (20) when the vehicle is in motion, including: establishing (19) a collection of characteristics of parasitic signals (Sp) stored in the wheel unit; comparing each motion signal (20) from the wheel unit (11) against the collection (19) of parasitic signals (Sp) stored in memory; and sending to a vehicle central processing unit (17) only those wheel unit signals (16) that are not present in the collection of parasitic signals.

Abstract: A method for self-calibrating, while a vehicle is moving, an accelerometer mounted on a wheel of the vehicle so that its plane of maximum sensitivity is secant with the axis of rotation of the wheel. The average value and on the other hand the amplitude of the signal representative of the acceleration Acc-read delivered by the accelerometer are calculated first, for an established speed of the vehicle, based on measurements performed by the accelerometer during a time window corresponding to the time needed for the wheel to complete n rotations, with n>1, then the values of the gain C1 and of the offset C2 of the accelerometer are determined by resolving the system of two equations with two unknown values: ?2R=C1×(average value of Acc-read)+C2 2 g=C1×(amplitude of Acc-read) with: ? the speed of rotation of the wheel, R the radius of the wheel.

Abstract: A method for locating the longitudinal position, either on the front chassis or on the rear chassis of a vehicle, of wheels (2) equipped with an electronic module (6) (or called wheel unit) designed to emit, to a central processing unit mounted on the vehicle, signals representative of operating parameters of each wheel. Each wheel (2) is equipped with a sensor (16) for measuring values representative of the norm of the Earth's magnetic field projected into the plane of the wheel, series of values measured simultaneously by the various sensors (16), representative of the variations of the norm of the Earth's magnetic field measured by each of the sensors, are compared so as to reveal a phase shift between the series, and the guiding wheels (2) are identified as being the wheels equipped with the sensors (16) originating the series of values in phase advance.

Abstract: A method for locating the longitudinal position of wheels (2, 3, 5, 6) of a vehicle (1) in which each wheel is fitted with a tangential measurement sensor (16) suitable for delivering measurement signals including a carrier of amplitudes and frequencies that are a function of the vibratory impacts sustained by the tangential measurement sensor. According to the invention, also, the amplitudes of the carrier of the signals in a frequency band corresponding to the frequencies of the explosions of the engine (M) are measured, the signals are compared so as to identify the signals of which the carriers have, for identical frequencies, maximum amplitudes, and the wheels (2, 3) that are the source of the signals of which the carriers have maximum amplitudes are located as corresponding to the wheels (2, 3) mounted on the driveshaft (4).

Abstract: A method for determining, while a vehicle is traveling, the length of the footprint on the ground of a tire (7) including a metal belt, fitted to a rim (6) of a wheel of the vehicle. According to the invention, this method includes mounting a magnetic sensor (16) on the rim (6) and analyzing the signal representing the magnetic field measured by the magnetic sensor, so as to detect the variations of the magnetic field resulting from the deformations sustained by a circumferential zone of the tire (7) situated opposite the magnetic sensor (8) when, respectively, the circumferential zone enters into contact with the ground and leaves the ground.

Abstract: The invention relates to a method for determining, while a vehicle is traveling, the length of the footprint on the ground of a tire (7) comprising a metal belt, fitted to a rim (6) of a wheel of said vehicle. According to the invention, this method consists in mounting a magnetic sensor (16) on the rim (6) and in analyzing the signal representing the magnetic field measured by said magnetic sensor, so as to detect the variations of the magnetic field resulting from the deformations sustained by a circumferential zone of the tire (7) situated opposite the magnetic sensor (8) when, respectively, said circumferential zone enters into contact with the ground and leaves the ground.

Abstract: A method of detecting the motion of a vehicle (13) of which at least one wheel unit (11) of said vehicle is equipped with a motion detection element (D) that generates a motion signal (20) when the vehicle is in motion, including: establishing (19) a collection of characteristics of parasitic signals (Sp) stored in the wheel unit; comparing each motion signal (20) from the wheel unit (11) against the collection (19) of parasitic signals (Sp) stored in memory; and sending to a vehicle central processing unit (17) only those wheel unit signals (16) that are not present in the collection of parasitic signals.