WO2024116256A1

WO2024116256A1 - Occupant detection device

Info

Publication number: WO2024116256A1
Application number: PCT/JP2022/043836
Authority: WO
Inventors: 章仁大西
Original assignee: 三菱電機株式会社
Priority date: 2022-11-29
Filing date: 2022-11-29
Publication date: 2024-06-06

Abstract

An occupant detection device (10) comprises: a camera unit (11) that includes an infrared camera (11b) which captures an image of the vehicle interior (51) of a vehicle (50), and an infrared illuminator (12) that radiates light toward the imaging range of the infrared camera (11b); an infrared illuminator (13) that radiates light toward the imaging range of the infrared camera (11b); and a radio wave sensor (14) that is provided integrally with the infrared illuminator (13) and detects an occupant (P) in the vehicle interior (51).

Description

Occupant detection device

This disclosure relates to an occupant detection device.

Conventionally, occupant detection devices have been provided that use cameras and various sensors to detect the status of occupants in a vehicle. In such occupant detection devices, for example, a structure that uses both a camera and a radio wave sensor is conceivable. Furthermore, when a camera is provided, a lighting device is required to illuminate the camera.

Incidentally, Patent Document 1 discloses a room lamp structure that integrates a radar module that detects occupants and a lighting module that shines light into the vehicle interior.

JP 2021-117202 A

In the above passenger detection device, when the angle of view of the camera is widened in order to expand the camera's imaging range, the number of illuminators must be increased in accordance with the expanded angle of view in order to obtain appropriate illuminance. Also, in the above passenger detection device, when properly illuminating a subject that is located far away from the camera, the number of illuminators must be increased.

Generally, the camera and illuminators are provided together as a camera unit. However, as mentioned above, if an attempt is made to expand the imaging range of the camera, the number of illuminators in the camera unit increases, leading to an increase in the size of the camera unit. To solve this problem, it is conceivable to separate the illuminators from the camera unit and install the separated illuminators in a different location within the vehicle cabin.

In contrast, the room lamp structure disclosed in Patent Document 1 is an integrated structure that combines a radar module for detecting occupants and a lighting module for shining light into the vehicle interior. This room lamp structure does not combine a radar module with a camera illuminator.

The present disclosure has been made to solve the problems described above, and aims to provide an occupant detection device that can ensure appropriate illumination for occupants while preventing the camera unit from becoming too large.

The occupant detection device disclosed herein includes a camera unit having a camera that captures an image of the interior of the vehicle cabin and a first illuminator that irradiates light toward the imaging range of the camera, a second illuminator that irradiates light toward the imaging range of the camera, and a radio wave sensor that is integral with the second illuminator and detects occupants in the cabin.

According to this disclosure, it is possible to ensure appropriate illumination for the occupants while preventing the camera unit from becoming too large.

1 is a side view of a vehicle equipped with an occupant detection device according to a first embodiment. 1 is a plan view of a vehicle equipped with an occupant detection device according to a first embodiment; 2 is a front view of a camera unit in the occupant detection device according to the first embodiment. FIG. 11 is a side view of a vehicle equipped with an occupant detection device according to a second embodiment. FIG. 11 is a plan view of a vehicle equipped with an occupant detection device according to a second embodiment. FIG. FIG. 1 is a side view of a vehicle equipped with a conventional occupant detection device. FIG. 11 is a front view of a camera unit in a conventional occupant detection device. FIG. 11 is a side view of a vehicle equipped with another conventional occupant detection device. FIG. 13 is a front view of a camera unit in another conventional occupant detection device.

To explain this disclosure in more detail, the form for implementing this disclosure will be described below with reference to the attached drawings.

Embodiment 1.
An occupant detection device 10 according to a first embodiment will be described with reference to FIGS. 1 to 3. FIG.

FIG. 1 is a side view of a vehicle 50 equipped with an occupant detection device 10 according to embodiment 1. FIG. 2 is a plan view of a vehicle 50 equipped with an occupant detection device 10 according to embodiment 1. FIG. 3 is a front view of a camera unit 11 in an occupant detection device 10 according to embodiment 1. Note that FIG. 2 shows a state in which the roof (ceiling 53) has been removed from the vehicle 50.

The vehicle 50 shown in FIG. 1 is equipped with a DMS (Driver Monitoring System) or OMS (Occupant Monitoring System) that monitors the status of an occupant P aboard the vehicle 50 using, for example, a camera and various sensors. The vehicle 50 also has an occupant detection device 10 that constitutes the DMS or OMS. The occupant detection device 10 detects an occupant P aboard the vehicle 50, and the DMS or OMS uses the detection results of the occupant detection device 10.

As shown in Figures 1 and 2, the occupant detection device 10 has a camera unit 11,

infrared illuminators

12, 13, and a radio wave sensor 14. In order to expand the monitoring function of, for example, a DMS or OMS, the occupant detection device 10 expands the imaging range of the camera unit 11 to the entire interior 51 of the vehicle 50, and complements the blind spots of the imaging range of the camera unit 11 with detection by the radio wave sensor 14. At this time, the occupant detection device 10 minimizes the number of

infrared illuminators

12, 13 by devising an arrangement of the

infrared illuminators

12, 13. The infrared illuminator 12 constitutes the first illuminator, and the infrared illuminator 13 constitutes the second illuminator.

The vehicle 50 has, for example, three rows of seats in the passenger compartment 51. Inside the passenger compartment 51, there are a driver's seat 52a and a passenger seat 52b which form the first row of seats, three rear seats 52c which form the second row of seats, and the two rearmost seats 52d which form the third row of seats. A passenger P who is the subject of the photograph can be seated in the driver's seat 52a, the passenger seat 52b, the rear seats 52c, and the rearmost seats 52d. A ceiling 53 is formed above the passenger compartment 51.

As shown in FIG. 1, the camera unit 11 is provided, for example, at the center in the vehicle width direction at the front edge of the ceiling 53. The camera unit 11 may also be provided on the dashboard, the rearview mirror, the overhead console, the A-pillar, etc.

As shown in FIG. 3, the camera unit 11 has one housing 11a, one infrared camera 11b, and one or more infrared illuminators 12.

The housing 11a is supported at the center of the vehicle width direction at the front edge of the ceiling 53 via a mounting plate (not shown) or the like. The housing 11a is rectangular when viewed from the front (when viewed from inside the vehicle compartment 51).

The infrared camera 11b captures images of the interior of the vehicle compartment 51. This infrared camera 11b is provided on the front side of the housing 11a, approximately in the center in the vehicle width direction. In this case, the infrared camera 11b is fixed so that it faces the rear side of the vehicle body. Note that the front side of the housing 11a is the surface that faces the inside of the vehicle compartment 51. In this way, by capturing images of the interior of the vehicle compartment 51, the infrared camera 11b is able to capture images of the conditions of the occupants P seated in the driver's seat 52a, passenger seat 52b, rear seat 52c, and rearmost seat 52d.

Furthermore, the infrared camera 11b has an image sensor 11c and a camera lens 11d. The camera lens 11d is arranged to cover the image sensor 11c from the front. The infrared camera 11b has an imaging range that includes the driver's seat 52a, the passenger seat 52b, the rear seat 52c, and the rearmost seat 52d. The angle of view of the infrared camera 11b is, for example, in the range of 100 degrees to 170 degrees.

The infrared illuminators 12 are used to illuminate the infrared camera 11b. The infrared illuminators 12 are provided on the front side of the housing 11a. For example, two infrared illuminators 12 are arranged on each side of the infrared camera 11b in the vehicle width direction. The illumination range 12a produced by the irradiation of these two infrared illuminators 12 is set to include the entire imaging range of the infrared camera 11b.

For example, the length of the illumination range 12a of the infrared illuminator 12 in the vehicle's fore-and-aft direction ranges from the driver's seat 52a and passenger seat 52b to the rear seat 52c. In addition, the illumination range 12a in the vehicle width direction of the infrared illuminator 12 includes the entire width of the passenger compartment 51.

The radio wave sensor 14 detects the state of the occupant P present in the vehicle compartment 51. This radio wave sensor 14 is, for example, a millimeter wave radar.

One radio wave sensor 14 and one or more infrared illuminators 13 are fixed together via a fixing member (not shown) or the like. These are fixed together and provided near the camera unit 11 on the ceiling 53. The infrared illuminators 13 and radio wave sensors 14 are disposed, for example, on the rear side of the vehicle body relative to the camera unit 11.

The infrared illuminator 13 is used to illuminate the infrared camera 11b. This infrared illuminator 13 and the infrared illuminator 12 provided in the camera unit 11 have the same configuration and function. The

infrared illuminators

12, 13 are, for example, LEDs (Light Emitting Diodes) and laser light sources. The infrared illuminators 13 are arranged, for example, one on each side of the radio wave sensor 14 in the vehicle width direction. The illumination range 13a produced by the irradiation of these two infrared illuminators 13 is set to include the entire imaging range or a portion of the imaging range of the infrared camera 11b.

Next, the effects of the occupant detection device 10 according to the first embodiment will be explained while comparing it with the conventional occupant detection device shown in Figures 6 to 9.

FIG. 6 is a side view of a vehicle 50 equipped with a conventional occupant detection device. FIG. 7 is a front view of a camera unit 11A in a conventional occupant detection device. FIG. 8 is a side view of a vehicle 50 equipped with another conventional occupant detection device. FIG. 9 is a front view of a camera unit 11B in another conventional occupant detection device.

The conventional occupant detection device shown in FIG. 6 detects only the state of an occupant (driver) P seated in the driver's seat 52a. As shown in FIG. 6 and FIG. 7, the conventional occupant detection device includes a camera unit 11A. This camera unit 11A includes a housing 11a, an infrared camera 11b, and two infrared illuminators 12.

In the conventional occupant detection device shown in FIG. 6, the angle of view of the infrared camera 11b is set, for example, in the range of 40 degrees to 60 degrees. The irradiation angle of the infrared illuminator 12 is set to approximately the same angle as the above-mentioned angle of view. The irradiation distance of the infrared illuminator 12 is set to a short distance corresponding to the distance from the camera unit 11A to the driver's seat 52a. In this case, the camera unit 11A can easily obtain the necessary illuminance for the imaging range 11e of the infrared camera 11b, which includes the driver's seat 52a. For this reason, in the camera unit 11A, it is sufficient that the infrared illuminator 12 is simply provided in close proximity to the infrared camera 11b.

The conventional occupant detection device shown in FIG. 8 has an imaging range 11e that is larger than the imaging range 11e of the conventional occupant detection device shown in FIG. 6. The conventional occupant detection device shown in FIG. 8 detects, as subjects, the states of occupants P seated in, for example, the driver's seat 52a, the passenger seat 52b, and the rear seat 52c. As shown in FIG. 8 and FIG. 9, the conventional occupant detection device includes a camera unit 11B. This camera unit 11B includes a housing 11a, an infrared camera 11b, and six infrared illuminators 12.

In other words, in the conventional occupant detection device shown in FIG. 8, the number of infrared illuminators 12 needs to be increased as the imaging range 11e of the infrared camera 11b expands. This makes the size of camera unit 11B larger than the size of camera unit 11A. As a result, the conventional occupant detection device shown in FIG. 8 results in an increase in the size of camera unit 11B.

In contrast, as shown in Figures 1 to 3, in the occupant detection device 10 according to embodiment 1, when the number of infrared illuminators 12 is increased in order to expand the imaging range 11e of the infrared camera 11b, the occupant detection device 10 disperses the

infrared illuminators

12, 13 between the camera unit 11 and the radio wave sensor 14. As a result, the occupant detection device 10 can make the size of the camera unit 11 smaller than the size of the camera unit 11B.

As described above, the occupant detection device 10 according to the first embodiment includes a camera unit 11 having an infrared camera 11b that captures an image of the interior of the vehicle cabin 51 of the vehicle 50 and an infrared illuminator 12 that irradiates light toward the imaging range of the infrared camera 11b, an infrared illuminator 13 that irradiates light toward the imaging range of the infrared camera 11b, and a radio wave sensor 14 that is integral with the infrared illuminator 13 and detects an occupant P in the vehicle cabin 51. As a result, the occupant detection device 10 can ensure appropriate illuminance for the occupant P while preventing the camera unit 11 from becoming too large.

Embodiment 2.
The occupant detection device 20 according to the second embodiment will be described with reference to Fig. 4 and Fig. 5. Fig. 4 is a side view of a vehicle 50 equipped with the occupant detection device 20 according to the second embodiment. Fig. 5 is a plan view of the vehicle 50 equipped with the occupant detection device 20 according to the second embodiment. Note that components having the same functions as those described in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The occupant detection device 20 according to the second embodiment has a structure in which the integrated infrared illuminator 13 and radio wave sensor 14 are moved toward the rear of the vehicle body compared to the structure of the occupant detection device 10 according to the first embodiment.

The integrated infrared illuminator 13 and radio wave sensor 14 are positioned in the center of the vehicle width direction, rearward of the driver's seat 52a and passenger seat 52b on the ceiling 53. Figures 5 and 6 show an example in which the integrated infrared illuminator 13 and radio wave sensor 14 are positioned directly above the rear seat 52c on the ceiling 53. The integrated infrared illuminator 13 and radio wave sensor 14 may also be positioned directly above the rearmost seat 52d on the ceiling 53.

In the occupant detection device 20, within the illumination range 12a of the infrared illuminator 12 provided on the camera unit 11, the portion toward the rear of the vehicle body that is farther away from the infrared illuminator 12 is prone to insufficient illumination. Therefore, the occupant detection device 20 positions the integrated infrared illuminator 13 and radio wave sensor 14 toward the rear of the vehicle body, so that the area where illumination is insufficient due to the infrared illuminator 12 can be supplemented by illumination from the infrared illuminator 13.

As described above, in the occupant detection device 20 according to the second embodiment, the infrared illuminator 13 and the radio wave sensor 14 are integrally arranged and positioned directly above the rear seat 52c or the rearmost seat 52d, which is located rearward of the driver's seat 52a. Therefore, the occupant detection device 20 can supplement the areas of the illumination range 12a of the infrared illuminator 12 that are insufficiently illuminable by illumination from the infrared illuminator 13.

Furthermore, within the scope of this disclosure, it is possible to freely combine the embodiments, modify any of the components of each embodiment, or omit any of the components of each embodiment.

The occupant detection device according to the present disclosure is suitable for use in occupant detection devices, etc., because the second illuminator, which is different from the first illuminator, and the radio wave sensor 14 are integrally provided, making it possible to prevent the camera unit from becoming too large.

10, 20 Occupant detection device, 11, 11A, 11B Camera unit, 11a Housing, 11b Infrared camera, 11c Image sensor, 11d Camera lens, 11e Imaging range, 12, 13 Infrared illuminator, 12a, 13a Illumination range, 14 Radio wave sensor, 50 Vehicle, 51 Vehicle interior, 52a Driver's seat, 52b Passenger seat, 52c Rear seat, 52d Rearmost seat, 53 Ceiling, P Occupant.

Claims

a camera unit including a camera for capturing an image of an interior of a vehicle and a first illuminator for emitting light toward an imaging range of the camera;
A second illuminator that irradiates light toward an imaging range of the camera;
an electric wave sensor provided integrally with the second illuminator, the electric wave sensor detecting an occupant in the vehicle compartment.
The occupant detection device according to claim 1 , wherein the second illuminator and the radio wave sensor are integrally provided at a central portion of a ceiling of the vehicle compartment in a vehicle width direction.
The second illuminator and the radio wave sensor, which are integrally provided, are disposed rearward of the vehicle body relative to the camera unit.
3. The occupant detection device according to claim 2.
The occupant detection device according to claim 1 , wherein the second illuminator and the radio wave sensor are disposed in a rearward direction of a driver's seat provided in the vehicle interior.
The occupant detection device according to claim 4, wherein the second illuminator and the radio wave sensor are disposed integrally with each other immediately above a rear seat located rearward of the driver's seat in the vehicle body.
The occupant detection device according to any one of claims 1 to 5, wherein the camera unit is provided at a front edge of a ceiling of the vehicle compartment at a central portion in a vehicle width direction.