FR3090520A1 - System for detecting the presence of a person occupying a rear seat of a vehicle - Google Patents

Abstract

System for detecting the presence of a person (1) occupying a rear seat (2) of a vehicle (3), comprising: - a vehicle starting device (3), of the hands-free type, intended to be activated by a first Bluetooth signal; - reception antennas (4a, 4b, 4c), arranged around the rear seats (2) to receive the first Bluetooth signal, and each comprising equipment (40) configured to transmit the measured power of the first Bluetooth signal received by the corresponding receiving antenna (4a, 4b, 4c); the equipment (40) being configured to communicate with each other via a second Bluetooth signal (S2); - a data processing unit (5), configured to: measure the link budgets of the second Bluetooth signal (S2) between the receiving antennas (4a, 4b, 4c), compare the measured link budgets to a reference situation where the rear seats (2) are free. Figure 1

Description

Description

Title of the invention: System for detecting the presence of a person occupying a rear seat of a vehicle

Technical area

The invention relates to the technical field of systems for detecting the presence of a person occupying a rear seat of a vehicle.

The invention finds particular application in the possibility of detecting the presence of a child left alone and of being able to warn the driver and / or the emergency authorities, for example to avoid a potentially fatal heat stroke.

State of the art

A system known from the prior art, in particular from document WO 2018/054823, comprises a detection unit which can include motion sensors, cameras or even ultrasonic sensors.

Such a prior art system is not entirely satisfactory insofar as it requires dedicated presence detection means, which adds an additional cost to the vehicle.

Statement of the invention

The invention aims to remedy all or part of the aforementioned drawbacks. To this end, the invention relates to a system for detecting the presence of a person occupying a rear seat of a vehicle, comprising:

- a vehicle starting device, of the hands-free type, intended to be activated by a first Bluetooth signal;

- reception antennas, arranged around the rear seats of the vehicle to receive the first Bluetooth signal, and each comprising equipment configured to transmit the measured power of the first Bluetooth signal received by the corresponding reception antenna; the devices being configured to communicate with each other via a second Bluetooth signal;

- a data processing unit, configured for:

measure the link budgets of the second Bluetooth signal between the receiving antennas, compare the measured link budgets to a reference situation where the rear seats of the vehicle are free.

[0006] Thus, such a system according to the invention makes it possible to detect the presence of a person occupying a rear seat of a vehicle using means used for starting the vehicle of the hands-free type, by Bluetooth activation. It is therefore not necessary to use dedicated detection means, contrary to the state of the art.

Detection can be carried out by the data processing unit by comparing the measured link budgets of the second Bluetooth signal (allowing communication between two antennas) to a reference situation where the rear seats of the vehicle are free. Indeed, a Bluetooth signal is an ultra high frequency radio wave, having a frequency of 2.4 GHz, and which makes it very sensitive to the human body. In other words, the second Bluetooth signal is greatly disturbed when a human body is present in the direction of propagation of the signal.

Definitions

- By "Bluetooth signal" means a signal using the "Bluetooth" communications standard, which is an ultra high frequency radio wave, having a frequency of 2.4 GHz.

- By "measured power" means the power in reception of the Bluetooth signal measured by the corresponding receiving antenna, that is to say the RSSI power ("Received Signal Strength Indication" in English).

- By "link budget" means a calculation to determine the quality of a link between two reception antennas, for example a signal to noise ratio.

- By "free" means that the rear seats are not occupied by a person.

The system according to the invention may include one or more of the following characteristics.

According to a characteristic of the invention, the reception antennas include first and second antennas each arranged on a center leg of the vehicle.

Thus, an advantage provided by such an arrangement is potentially obtaining significant and symmetrical coverage of the rear passenger compartment of the vehicle.

According to a characteristic of the invention, the first and second antennas are arranged at an upper end portion of the corresponding center leg.

According to a characteristic of the invention, the reception antennas comprise a third antenna arranged behind the rear seats of the vehicle, in a central position.

Thus, an advantage provided is to obtain, in conjunction with the first and second antennas, significant and symmetrical coverage of the rear passenger compartment of the vehicle.

According to a characteristic of the invention, the third antenna is arranged on the floor of the trunk of the vehicle.

According to a characteristic of the invention, the data processing unit is configured to measure:

- the link budget of the second Bluetooth signal between the third antenna and the first antenna;

- the link budget of the second Bluetooth signal between the third antenna and the second antenna.

Thus, an advantage provided is to be able to detect the presence of an occupant:

- the central office if the link budget between the third antenna and the first antenna is disturbed, and if the link budget between the third antenna and the second antenna is similarly disturbed;

- the seat located on the side of the first antenna if the link budget between the third antenna and the first antenna is disturbed;

- the seat located on the side of the second antenna if the link budget between the third antenna and the second antenna is disturbed.

The term "disturbed" means that the link budget does not comply with the reference situation where the rear seats of the vehicle are free.

According to a characteristic of the invention, the equipment of the receiving antennas is configured to communicate with each other by low energy Bluetooth.

According to a characteristic of the invention, the equipment of the receiving antennas is configured to communicate with the data processing unit by low energy Bluetooth.

According to a characteristic of the invention, the first Bluetooth signal is generated by a multifunction mobile.

The term "multifunction mobile" means a "Smartphone" in the English language. The invention also relates to a vehicle comprising a system according to the invention.

Brief description of the drawings

Other characteristics and advantages will appear in the detailed description of different embodiments of the invention, the presentation being accompanied by examples and references to the accompanying drawings.

[Fig.l]

Figure 1 is a schematic top view illustrating the operating principle of a system according to the invention. The arrows show the intravehicular communications, between the receiving antennas and between a receiving antenna and the data processing unit. The dotted lines show the disturbance of the second Bluetooth signal in the presence of a person in the rear of the vehicle.

Detailed description of the embodiments

Identical elements or ensuring the same function will have the same references for the different embodiments, for the sake of simplification.

An object of the invention is a system for detecting the presence of a person 1 occupying a rear seat 2 of a vehicle 3, comprising:

- a vehicle starting device 3, of the hands-free type, intended to be activated by a first Bluetooth signal;

- reception antennas 4a, 4b, 4c, arranged around the rear seats 2 of the vehicle 3 to receive the first Bluetooth signal, and each comprising equipment 40 configured to transmit the measured power of the first Bluetooth signal received by the reception antenna 4a, 4b, 4c corresponding; the equipment 40 being configured to communicate with each other via a second S2 Bluetooth signal;

- a data processing unit 5, configured for:

measure the link budgets of the second S2 Bluetooth signal between the reception antennas 4a, 4b, 4c, compare the link budgets measured with a reference situation where the rear seats 2 of the vehicle 3 are free.

Vehicle starting device

The first Bluetooth signal is advantageously generated by a multifunction mobile. The vehicle starting device can also have a hands-free access function to the vehicle 3 by the first Bluetooth signal generated by the multifunction mobile.

Reception antennas

The receiving antennas advantageously comprise first and second antennas 4a, 4b each arranged on a middle leg 6 of the vehicle 3. The first and second antennas 4a, 4b are advantageously arranged at an upper end portion of the middle leg 6 corresponding.

The receiving antennas advantageously comprise a third antenna 4c arranged behind the rear seats 2 of the vehicle 3, in a central position. The third antenna 4c is advantageously arranged on the floor 7 of the boot of the vehicle 3.

The equipment 40 of the receiving antennas 4a, 4b, 4c are advantageously configured to communicate with each other by low energy Bluetooth (BLE for "Bluetooth Low Energy" in English). The equipment 40 of the receiving antennas 4a, 4b, 4c are advantageously configured to communicate with the data processing unit 5 by Bluetooth at low energy.

Data processing unit

The data processing unit 5 is advantageously configured to measure:

- the link budget of the second S2 Bluetooth signal between the third antenna 4c and the first antenna 4a;

- the link budget of the second S2 Bluetooth signal between the third antenna 4c and the second antenna 4b.

[0040] Thus, when the vehicle is started, it is possible to detect the presence of a person 1 occupying:

the central rear seat 2 if the link budget between the third antenna 4c and the first antenna 4a is disturbed, and if the link budget between the third antenna 4c and the second antenna 4b is similarly disturbed;

- the rear seat 2 located on the side of the first antenna 4a if the link budget between the third antenna 4c and the first antenna 4a is disturbed;

- The rear seat 2 located on the side of the second antenna 4b if the link budget between the third antenna 4c and the second antenna 4b is disturbed.

The data processing unit 5 will carry out the measurements again when the vehicle 3 is locked in order to detect whether a person 1 remains in the vehicle 3.

The data processing unit 5 is advantageously integrated into the vehicle starting device 3, more precisely into its SDCM ("Smart Device Control Management") control unit.

The invention is not limited to the embodiments described. A person skilled in the art is able to consider their technically effective combinations, and to substitute equivalents for them.

Claims (1)

Claims [Claim 1] System for detecting the presence of a person (1) occupying a rear seat (2) of a vehicle (3), comprising: - a vehicle starting device (3), of the hands-free type, intended to be activated by a first Bluetooth signal; - reception antennas (4a, 4b, 4c), arranged around the rear seats (2) of the vehicle (3) to receive the first Bluetooth signal, and each comprising equipment (40) configured to transmit the measured power of the first signal Bluetooth received by the corresponding receiving antenna (4a, 4b, 4c); the equipment (40) being configured to communicate with each other via a second Bluetooth signal (S2); - a data processing unit (5), configured to: measure the link budgets of the second Bluetooth signal (S2) between the receiving antennas (4a, 4b, 4c), compare the measured link budgets to a reference situation where the rear seats (2) of the vehicle (3) are free. [Claim 2] System according to claim 1, in which the reception antennas (4a, 4b, 4c) comprise first and second antennas (4a, 4b) each arranged on a center leg (6) of the vehicle (3). [Claim 3] The system of claim 2, wherein the first and second antennas (4a, 4b) are arranged at an upper end portion of the corresponding center leg (6). [Claim 4] System according to claim 2 or 3, in which the reception antennas (4a, 4b, 4c) comprise a third antenna (4c) arranged behind the rear seats (2) of the vehicle (3), in a central position. [Claim 5] System according to claim 4, in which the third antenna (4c) is arranged on the floor (7) of the boot of the vehicle (3). [Claim 6] System according to claim 4 or 5, in which the data processing unit (5) is configured to measure: - the link budget of the second Bluetooth signal (S2) between the third antenna (4c) and the first antenna (4a); - the link budget of the second Bluetooth signal (S2) between the third antenna (4c) and the second antenna (4b). [Claim 7] System according to one of Claims 1 to 6, in which the equipment (40) of the reception antennas (4a, 4b, 4c) are configured to communicate with each other by low energy Bluetooth. [Claim 8] System according to one of Claims 1 to 7, in which the equipment (40) of the receiving antennas (4a, 4b, 4c) is configured to communicate with the data processing unit (5) by Bluetooth at low energy. [Claim 9] System according to one of Claims 1 to 8, in which the first Bluetooth signal is generated by a multifunction mobile. [Claim 10] Vehicle (3) comprising a system according to one of claims 1 to 9. 1/1