JP2021109604A - Fitting state detection device - Google Patents

Abstract

To accurately detect a fitting state of webbing of an occupant.SOLUTION: A fitting detection device 30 photographs reflection light of first infrared rays IrA emitted from a first light source 32A by a camera 34A, and photographs reflection light of second infrared rays IrB emitted from a light source 32B by a camera 34B. A detection controller 36 detects a webbing fitting state of an occupant D from a difference image between the photographed image of the first infrared rays IrA and the photographed image of the second infrared rays IrB. A webbing 14 fit to the crew member D is provided with a mark 46 for absorbing the first infrared rays IrA. Thereby, the mark 46 of the webbing 14 can be accurately detected from the difference image between the photographed image of the first infrared rays IrA and the photographic image of the second infrared rays IrB, which can accurately detect whether or not the occupant D properly fits the webbing 14.SELECTED DRAWING: Figure 1

Description

The present invention relates to a wearing state detecting device that detects a webbing wearing state of an occupant.

In Patent Document 1, a pattern that allows the seatbelt itself and the seatbelt extension direction to be recognized is attached to the seatbelt by using a material that reflects infrared rays. Further, the occupant monitoring device of Patent Document 1 photographs an occupant seated on a seat with an infrared camera, identifies a seatbelt included in the captured image, and estimates the seatbelt wearing state of the occupant.

Japanese Unexamined Patent Publication No. 2018-118671

By the way, some materials used for occupant's clothing reflect not only visible light but also infrared light (infrared light). Therefore, even if a material that reflects infrared rays is used for the seat belt, it may be difficult to accurately identify the seat belt from the infrared photographed image depending on the design and pattern of the occupant's clothing.

The present invention has been made in view of the above facts, and an object of the present invention is to provide a wearing state detecting device capable of accurately detecting the wearing state of a webbing of an occupant.

The wearing state detection device of the first aspect is the irradiation means for irradiating each of the first infrared rays and the second infrared rays having different wavelengths from the front of the seat on which the occupant sits toward the seat, and the webbing of the seat belt device. From the first optical characteristic unit provided on the front surface when the occupant seated in the seat has the peak wavelength of the optical characteristic of light absorption or light reflection as the wavelength of the first infrared ray, and the irradiation means. From the imaging means that images each of the first infrared ray and the second infrared ray that is irradiated and reflected from the front of the seat, and the difference image between the photographed image of the first infrared ray and the photographed image of the second infrared ray, the said A detection means for detecting the wearing state of the webbing of the occupant seated in the seat is provided.

In the first aspect, the mounting state detection device of the second aspect is provided on the surface of the webbing opposite to the first optical characteristic portion, and has optical characteristics corresponding to the optical characteristics of the first optical characteristic portion. Includes a second optical characteristic section in which the wavelength of the peak of is the wavelength of the second infrared ray.

In the second correspondence, the mounting state detection device of the third aspect has the first difference image obtained by subtracting the second infrared captured image from the first infrared captured image as the difference image, and the detection means. The wearing state of the webbing is detected by using the second difference image obtained by subtracting the photographed image of the first infrared ray from the photographed image of the second infrared ray.

In the wearing state detection device of the first aspect, each of the first infrared rays and the second infrared rays having different wavelengths is irradiated from the front of the seat on which the occupant is seated toward the seat by the irradiation means, and is irradiated and reflected from the irradiation means. Each of the first infrared ray and the second infrared ray to be imaged is imaged from the front of the seat by the imaging means. Further, the detection means detects the wearing state of the webbing of the occupant seated in the seat from the difference image between the photographed image of the first infrared ray and the photographed image of the second infrared ray.

Here, in the webbing of the seatbelt device, the wavelength of the peak of the optical characteristics of light absorption or light reflection is set to the wavelength of the first infrared ray on the front surface (surface) when the occupant seated in the seat wears it. A first optical characteristic unit is provided. Therefore, when the optical characteristic of the first optical characteristic unit is the light absorption characteristic, the occupant seated in the seat wears the webbing, and the first infrared ray captured image is provided with the first optical characteristic unit provided on the webbing. Does not appear. Further, when the optical characteristic of the first optical characteristic portion is the light reflection characteristic, the first optical characteristic portion provided on the webbing becomes brighter in the captured image of the first infrared ray than the captured image of the second infrared ray. appear. That is, when the first optical characteristic portion has the light absorption characteristic, the captured image of the first infrared ray is an image in which the portion of the first optical characteristic portion is omitted, and when the first optical characteristic portion has the light reflection characteristic, the first image is obtained. In the 1-infrared photographed image, the portion of the first optical characteristic portion becomes a bright image.

As a result, regardless of the material, pattern, and design of the occupant's clothing, the first light absorption part of the webbing can be easily detected from the difference image between the photographed image of the first infrared ray and the photographed image of the second infrared ray, and the occupant's clothing can be detected. The wearing state of the webbing can be detected accurately.

In the mounting state detection device of the second aspect, the wavelength of the peak of the optical characteristic corresponding to the optical characteristic of the first optical characteristic portion is the second infrared ray on the surface (back surface) opposite to the first optical characteristic portion of the webbing. A second optical characteristic unit having a wavelength of is provided.

Therefore, when the first optical characteristic portion and the second optical characteristic portion each have light absorption characteristics, the first infrared ray is photographed in the state of wearing the webbing in which the first optical characteristic portion on the surface is on the front side. The first optical characteristic unit can be detected from the image. Further, in the mounted state of the webbing in which the second optical characteristic portion on the back surface is on the front side, the second optical characteristic portion can be detected from the captured image of the second infrared ray. As a result, the twist of the webbing can be detected, and the webbing wearing state of the occupant can be detected more accurately from the difference image between the captured image of the first infrared ray and the captured image of the second infrared ray.

In the wearing state detection device of the third aspect, as the difference image, the first difference image obtained by subtracting the second infrared image from the first infrared image and the first infrared image obtained by subtracting the second infrared image from the second infrared image are obtained. The wearing state of the webbing is detected using the subtracted second difference image. As a result, even if the webbing is twisted in front of the occupant's body so that a part of the front surface and a part of the back surface are on the front side, the wearing state of the webbing can be detected more accurately.

It is a block diagram which shows the schematic structure of the wearing detection device which concerns on this embodiment. (A) is a front view of a main part of a vehicle showing a seatbelt device, and (B) is a schematic view showing a main part of a webbing. It is a diagram which shows the outline of the light absorption characteristic of a light absorption member. It is a flow chart which shows the outline of the attachment detection process which concerns on this Embodiment. (A) to (C) are schematic views showing a webbing wearing state, a photographed image and a difference image according to the webbing wearing state, respectively, (A) is a proper webbing wearing state, and (B) is a slip joint. The side-twisted webbing wearing state and (C) show each of the twisted webbing wearing states in the shoulder belt portion. It is a block diagram which shows the schematic structure of the driver monitor system which concerns on the modification. It is the schematic which shows each of the webbing wearing state which provided the mark which has the light reflection characteristic on the webbing, the photographed image and the difference image according to the webbing wearing state.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
The seatbelt device 10 as the occupant protection device according to the present embodiment is provided in the seat 12 on which an occupant (driver or the like) is seated in the vehicle. FIG. 1 shows a side view of the main part of the seat 12 as viewed from the inside in the vehicle width direction, and FIG. 2A shows a front view of the main part of the seat 12 as viewed from the front side of the vehicle. In FIG. 2B, the main part of the seatbelt device 10 is shown in a schematic view. In the drawings, the front of the vehicle is indicated by an arrow FR, the inside in the vehicle width direction is indicated by an arrow IN, and the upper portion is indicated by an arrow UP. Further, in the present embodiment, the driver's seat among the front seats will be described as an example of the seat 12, but the seat 12 may be another seat such as a passenger seat or a rear seat.

As shown in FIGS. 1 and 2 (A), in the seat 12, the seat back 12B is attached to the rear side portion of the seat cushion 12A and the front side is directed to the front side of the vehicle, and the occupant D seated on the seat 12 The body is turned to the front of the vehicle. The front side of the seat 12 is not limited to the front side of the vehicle, and the front side may face inward in the vehicle width direction.

As shown in FIG. 2A, the seatbelt device 10 is a three-point type, and the seatbelt device 10 has a long strip-shaped webbing 14 for occupant restraint, a webbing winding device 16, and a webbing winding device 16. A buckle device 18 is provided. The webbing take-up device 16 is fixed to the vehicle body at the lower end of the center pillar (not shown) outside the vehicle width direction of the seat 12, and the webbing 14 is one end side in the longitudinal direction of the webbing take-up device 16. It is wound up from the base end side and stored so that it can be pulled out.

A slip joint 20 is arranged above the webbing take-up device 16, and the slip joint 20 is attached to the upper part of the center pillar. The webbing 14 drawn from the webbing winding device 16 is wound around the slip joint 20 and folded back. Further, in the webbing 14, the tip portion folded back by the slip joint 20 is locked to the anchor plate 22, and the anchor plate 22 is fixed to the vehicle body (may be the frame of the seat 12) at the lower part of the center pillar. There is.

As shown in FIGS. 1 and 2 (A), the buckle device 18 is composed of a buckle 24 and a tongue 26 engaged with the buckle 24, and the buckle 24 is a vehicle body (inward in the vehicle width direction of the seat 12). It may be the frame of the seat 12). Further, a webbing 14 is slidably inserted between the slip joint 20 and the anchor plate 22 in the tongue 26.

In the seatbelt device 10, the occupant D seated on the seat 12 grips the tongue 26, pulls out the webbing 14 from the webbing take-up device 16, and engages the tongue 26 with the buckle 24, so that the webbing 14 is attached to the occupant D. Will be done. Further, the webbing take-up device 16 urges the webbing 14 worn by the occupant D in the take-up direction. As a result, the slack of the webbing 14 is removed so that the webbing 14 is brought into close contact with the body of the occupant D, and the occupant D is restrained by the webbing 14 in a protective manner in an emergency such as a vehicle emergency. The seatbelt device 10 has a configuration in which the webbing take-up device 16 is arranged inside the seat back 12B near the shoulder portion of the seat 12, and the webbing 14 is pulled out from the upper portion of the shoulder portion of the occupant D. May be good.

In the proper mounting state of the webbing 14 on the occupant D, the surface 50A of the webbing 14 is the front side of the shoulder belt portion 14A extending from the shoulder portion to the waist portion of the occupant D. FIG. 2B shows the back surface 50B side of the shoulder belt portion 14A of the webbing 14.

As shown in FIG. 2B, the webbing 14 is twisted at the portion on the slip joint 20 side, so that the back surface 50B of all or part of the shoulder belt portion 14A of the webbing 14 is directed to the front side. This is an example of an improperly attached state (non-attached state).

On the other hand, the vehicle is provided with a mounting detection device 30 as a mounting state detection device according to the present embodiment. The wearing detection device 30 targets the webbing 14 worn by the occupant D seated in the seat 12 as a detection target, and detects the wearing state of the webbing 14 of the occupant D. FIG. 1 shows a schematic configuration of the mounting detection device 30 in a block diagram.

As shown in FIG. 1, the wearing detection device 30 includes an illuminator 32 as an irradiation means, a camera 34 as an imaging means, and a detection controller (wearing detection ECU) 36 including the detection means. The illuminator 32 is arranged on the front side of the seat 12, and the illuminator 32 irradiates the seat 12 with infrared Ir of a predetermined wavelength which is invisible light, and the illuminator 32 and the occupant D seated in the seat 12 occupy the illuminator 32. Illuminates the webbing 14 worn by D.

An image sensor such as a CMOS sensor or a CCD sensor is used in the camera 34. The camera 34 is arranged on the front side of the seat 12, and the camera 34 is irradiated toward the seat 12, and the infrared Ir (infrared Ir) reflected by the webbing 14 worn by the occupant D together with the occupant D seated in the seat 12. (Reflected light) is imaged.

The illuminator 32 and the camera 34 are arranged on the windshield glass (not shown) of the vehicle and mounted on the ceiling. It is sufficient that the illuminator 32 irradiates at least the upper body of the occupant D seated in the seat 12 (for example, above the waist portion) with infrared Ir, and the camera 34 can image at least the upper body of the occupant D seated in the seat 12. The illuminator 32 and the camera 34 may be mounted on the instrument panel 28 as long as they do not obstruct the view of the occupant D, and one of the illuminator 32 and the camera 34 may be mounted on the ceiling. The other may be attached to the instrument panel 28.

Near infrared rays (infrared rays having a wavelength of about 770 nm to about 3 μm) are applied to the wearing detection device 30 as infrared Irs, and the first infrared IrA and the first infrared rays IrA having different wavelengths as infrared Irs are applied to the wearing detection device 30. 2 Infrared IrB is used. In the present embodiment, the wavelength λA of the first infrared IrA is 850 nm (λA = 850 nm), and the wavelength λB of the second infrared IrB is 940 nm (λB = 940 nm).

As the illuminator 32, an illuminator 32A that emits the first infrared IrA and an illuminator 32B that emits the second infrared IrB are used, and a light emitting diode (LED) or the like can be applied to the illuminators 32A and 32B. The illuminator 32 may have a configuration in which the illuminator 32A and the illuminator 32B are integrated, and the first infrared IrA and the second infrared IrB are individually emitted (lit).

A camera 34A that captures an image of the first infrared IrA and a camera 34B that captures an image of the second infrared IrB are applied to the camera 34. The camera 34A is provided with a filter through which the first infrared IrA is transmitted, and the camera 34B is provided with a filter through which the second infrared IrB is transmitted.

In the mounting detection device 30, the reflected light of the first infrared ray IrA emitted from the illuminator 32A toward the seat 12 is imaged by the camera 34A, and the reflection of the second infrared ray IrB emitted from the illuminator 32B toward the seat 12 is captured. The light is imaged by the camera 34B. The mounting detection device 30 may be configured to capture each of the reflected light of the first infrared ray IrA and the reflected light of the second infrared ray IrB by using one camera 34. Further, the cameras 34A and 34B do not have to be provided with a filter for transmitting infrared rays. In these cases, the detection controller 36 may extract images of the frequency (wavelength) components of the first infrared IrA and the second infrared IrB from the captured image.

The detection controller 36 is formed with an image pickup control unit 38, an image processing unit 40 as an image processing means, a difference image generation unit 42 as a difference image generation means, and a determination unit 44 as a determination means. The detection controller 36 is provided with a microcomputer (not shown) in which a CPU, RAM, ROM, storage as a non-volatile memory, an input / output interface, and the like are connected to a bus. In the detection controller 36, the program stored in the ROM and the storage is read by the CPU and executed while being expanded in the RAM, so that the imaging control unit 38, the image processing unit 40, the difference image generation unit 42, and the determination unit 44 are executed. The function is realized.

Each of the illuminator 32 (32A, 32B) and the camera 34 (34A, 34B) is connected to the detection controller 36. The image pickup control unit 38 of the detection controller 36 controls the cameras 34A and 34B to take an image in synchronization with the light emission of the illuminators 32A and 32B. At this time, the image pickup control unit 38 irradiates the first infrared IrA from the illuminator 32A, images the reflected light of the first infrared IrA by the camera 34A, irradiates the second infrared IrB from the illuminator 32B, and irradiates the camera. The reflected light of the second infrared IrB is imaged by 34B.

The captured images of the cameras 34A and 34B are output to the image processing unit 40. The image processing unit 40 captures each of the captured image of the first infrared IrA captured by the camera 34A and the captured image of the second infrared IrB captured by the camera 34B, and performs predetermined image processing for each of the captured images. To execute. Further, the image processing unit 40 normalizes each of the captured image of the first infrared IrA and the captured image of the second infrared IrB so that the brightness level of each captured image becomes the same. As a result, the image processing unit 40 generates the first infrared image PA in which the captured image of the first infrared IrA is normalized, and also generates the second infrared image PB in which the captured image of the second infrared IrB is normalized. do.

The difference image generation unit 42 uses the first infrared image PA and the second infrared image PB, extracts the difference from the other using one as the background image, and generates the difference image DP obtained by binarizing the extracted image. do. The difference image DP may be generated after each of the first infrared image PA and the second infrared image PB is binarized, and is two with respect to the difference image of the first infrared image PA and the second infrared image PB. It may be digitized.

Here, the difference image generation unit 42 generates a first difference image DPA obtained by extracting the difference of the background image from the first infrared image PA with the second infrared image PB as the background image as the difference image DP. Further, the difference image generation unit 42 generates a second difference image DPB obtained by extracting the difference of the background image from the second infrared image PB with the first infrared image PA as the background image as the difference image DP. As a result, the first difference image DPA and the second difference image DPB are generated from the first infrared image PA and the second infrared image PB, and are output to the determination unit 44.

The determination unit 44 uses the first difference image DPA and the second difference image DPB to determine whether or not the webbing 14 is attached from the image of the webbing 14, and whether or not the webbing 14 is in an appropriate attached state. Judgment is made and the judgment result is output.

On the other hand, as shown in FIG. 2A, a marker and a mark 46 as a first optical characteristic portion are arranged on the webbing 14 of the seatbelt device 10. When the occupant D wears the webbing 14, the mark 46 is formed on the surface 50A (the surface opposite to the occupant D) of the shoulder belt portion 14A in a substantially band shape along the longitudinal direction of the webbing 14.

Further, as shown in FIG. 2B, a marker and a mark 48 as a second optical characteristic portion are arranged on the webbing 14. The mark 48 is formed on the back surface 50B of the shoulder belt portion 14A in a substantially band shape along the longitudinal direction of the webbing 14.

For marks 46 and 48, an optical characteristic member having an optical characteristic having a light reflection characteristic or a light absorption characteristic with respect to infrared rays having a specific wavelength in the infrared region and having a peak of the optical characteristic at a specific wavelength is used. Has been done. In the present embodiment, the light absorption characteristic is applied as the optical characteristic of the marks 46 and 48, and the mark 46 and 48 are light absorption members (infrared rays) having a peak of the light absorption characteristic (infrared absorption characteristic) in the infrared ray of a specific wavelength. Absorption member) is used. FIG. 3 is a schematic diagram showing a change in absorption degree with respect to wavelength as a light absorption characteristic of a near-infrared absorbing material (light absorbing member) that absorbs near-infrared rays (light) in a specific wavelength region of the near-infrared region. Has been done.

As shown in FIG. 3, the maximum absorption wavelength at which the peak of the light absorption characteristic is about 754 nm for the light absorption member CM-A, about 807 nm for the light absorption member CM-B, about 853 nm for the light absorption member CM-C, and light. The absorption member CM-D is about 911 nm, the light absorption member CM-E is about 956 nm, and the light absorption member CM-F is about 1014 nm (1.014 μm).

Here, for the mark 46 on the surface 50A of the webbing 14, a light absorbing member CM-C in which the wavelength of the peak of the light absorption characteristic is close to (substantially the same as) the wavelength λA of the first infrared IrA is used. Further, for the mark 48 on the back surface 50B of the webbing 14, a light absorbing member CM-E in which the wavelength of the peak of the light absorption characteristic is close to (substantially the same as) the wavelength λB of the second infrared IrB is used.

The marks 46 and 48 may be formed by using a material containing the light absorbing members CM-C and CM-E and applying the material to the webbing 14, and the marks 46 and 48 are formed so as to coat the webbing 14 with the material. The material may be woven into the webbing 14 to form the material. Further, for the marks 46 and 48, a thermocompression bonding sheet is used, and a material including the light absorbing members CM-C and CM-E may be attached to the webbing 14 by thermocompression bonding.

Further, the marks 46 and 48 are not limited to strips, and may be provided so as to form various patterns and patterns such as a striped pattern and a check pattern, and the marks 46 and 48 may be colored and colorless. (The color of the material of the webbing 14 appears). Further, the mark 46 and the mark 48 may form different colors, patterns or patterns, and the front surface 50A and the back surface 50B of the webbing 14 may be provided so as to be identifiable by the occupant D. As a result, the webbing 14 can be given a design.

The mounting detection device 30 configured in this way is made operable by the electric power supplied from the power source of the vehicle. FIG. 4 is a flow chart showing an outline of the detection process executed by the detection controller 36 when the mounting detection device 30 operates.

When the occupant D who got on the vehicle sits on the seat 12, he wears the webbing 14 of the seatbelt device 10. The detection controller 36 of the wearing detection device 30 starts the detection process at the timing set to detect the webbing wearing state of the occupant D, and determines the webbing wearing state of the occupant D.

The detection process for determining the webbing wearing state of the occupant D may be started when an ignition switch (not shown) is turned on so that the vehicle can travel. Further, when the seat 12 is provided with a seat switch (not shown) for detecting the seating of the occupant D, the detection process may be started when the seat switch is turned on. Further, when the buckle device 18 of the seatbelt device 10 is provided with a buckle switch (not shown) for detecting whether or not the tongue 26 is engaged with the buckle 24, the detection process is performed by the buckle switch. It may be started by detecting that the buckle 24 is engaged. The detection process may be terminated by detecting that the occupant D has properly attached the webbing 14, and is set in advance after detecting that the occupant D has properly attached the webbing 14. It may be repeatedly executed every time, and the wearing state of the webbing 14 may be monitored.

In the flowchart of FIG. 4, an image is taken using the first infrared IrA in step 100, and an image is taken using the second infrared IrB in the next step 102. In the imaging using the first infrared IrA, the reflected light of the first infrared IrA is imaged by the camera 34A while the illuminator 32A is made to emit light and the seat 12 is illuminated with the first infrared IrA. Further, in the imaging using the second infrared IrB, the reflected light of the second infrared IrB is imaged by the camera 34B while the illuminator 32B is made to emit light to illuminate the seat 12 with the second infrared IrB.

In step 104, image processing is performed on the captured images of the first infrared IrA and the second infrared IrB. As a result, the first infrared image PA and the second infrared image PB are generated.

In the next step 106, a difference image DP using the first infrared image PA and the second infrared image PB is generated. As the difference image DP, at least the first difference image DPA with the second infrared image PB as the background image is generated. Further, as the difference image DP, a second difference image DPB using the first infrared image PA as a background image is generated. After that, in step 108, the determination unit 44 determines the webbing wearing state of the occupant D using the difference image DP (first difference image DPA and second difference image DPB).

5 (A) to 5 (C) show the webbing wearing state of the occupant D seated in the seat 12, the first infrared image PA, the second infrared image PB, and the difference image DP (at least one of the difference image DPA and DPB). ) Are schematically shown. In the drawings, the stronger the reflected light (the brighter it is), the blacker it is, and the weaker the reflected light (the darker it is), the whiter it is.

Here, FIG. 5A corresponds to a state in which the webbing 14 is properly mounted, FIG. 5B corresponds to a state in which the shoulder belt portion 14A of the webbing 14 is inverted, and FIG. 5C corresponds to a state in which the shoulder belt portion 14A of the webbing 14 is inverted. , It corresponds to the twisted state in the middle part of the shoulder belt part 14A of the webbing 14. Further, in FIG. 5B, a material having a property of absorbing infrared rays is used for the occupant D's clothing 52, and in FIG. 5C, infrared rays are applied to substantially the entire occupant D's clothing 54 (at least the front surface). A material having the property of absorbing infrared rays is used.

As shown in FIG. 5A, in the proper mounting state of the webbing 14, the shoulder belt portion 14A has a substantially straight line at an angle, and the surface 50A of the shoulder belt portion 14A on which the mark 46 is formed is on the front side. Therefore, the first infrared IrA emitted from the illuminator 32A is absorbed at the mark 46 (the reflection of the first infrared IrA is suppressed at the mark 46). Further, in the portion other than the mark 46, the reflection of the first infrared IrA occurs. As a result, in the first infrared image PA imaged using the first infrared IrA, the image density (brightness of the first infrared IrA) differs between the mark 46 portion and the portion other than the mark 46.

On the other hand, the second infrared IrB emitted from the illuminator 32B is reflected without being absorbed even at the mark 46. Therefore, in the second infrared image PB imaged using the second infrared IrB, the entire image density (brightness) is substantially the same.

As a result, the mark 46 on the webbing 14 appears in the first difference image DPA obtained by subtracting the background image from the first infrared image PA with the second infrared image PB as the background image. By comparing this mark 46 with a preset template, it is possible to determine whether or not the webbing wearing state of the occupant D is appropriate. For example, if the mark 46 on the first difference image DPA is diagonally substantially straight, it is determined that the webbing mounting state is appropriate.

On the other hand, when the mark 46 on the first difference image DPA is a greatly curved image (not shown), the webbing 14 worn by the occupant D is greatly bent, and there is a problem in the webbing wearing state. It is determined that there is (the webbing wearing state is not appropriate).

Further, when the occupant D is not equipped with the webbing 14 (when the webbing is not attached), not only the second infrared IrB but also the first infrared Ir is not absorbed. Therefore, neither the mark 48 nor the mark 46 appears in either the first difference image DPA or the second difference image DPB, so it is determined that the webbing wearing state is not appropriate (webbing is not mounted).

As shown in FIG. 5B, when the slip joint 20 side of the shoulder belt portion 14A of the webbing 14 worn by the occupant D is twisted, the back surface 50B of the shoulder belt portion 14A on which the mark 48 is formed is formed. It will be on the front side. Therefore, at the mark 48 of the webbing 14, the first infrared IrA emitted from the illuminator 32A is reflected, but the second infrared IrB emitted from the illuminator 32B is absorbed (at the mark 48, the second infrared IrB is absorbed). Reflection is suppressed).

Further, a general infrared absorbing material having light absorption characteristics in the infrared region (particularly the near infrared region) absorbs infrared rays in substantially the entire range of the near infrared region. Therefore, when the pattern 52A having the infrared ray absorbing characteristic is formed on the clothes 52 of the occupant D, each of the first infrared ray IrA irradiated from the illuminator 32A and the second infrared ray IrB irradiated from the illuminator 32B It is absorbed by the pattern 52A of the clothing 52 and reflected by the portion other than the pattern 52A.

As a result, in each of the first infrared image PA imaged using the first infrared IrA and the second infrared image PB imaged using the second infrared IrB, the portion of the clothing 52 other than the pattern 52A and the pattern 52A The image density (brightness of the image) is different between and. Further, in the first infrared image PA imaged using the first infrared IrA, the image densities are similar between the mark 48 portion and the portion other than the mark 48, but the second infrared image IrB imaged using the second infrared IrB. In the infrared image PB, the image density (brightness of the second infrared IrB) is different between the portion of the mark 48 and the portion other than the mark 48.

In each of the first infrared image PB and the second infrared image PB, the image density of the pattern 52A is different from that of the surroundings, so that the first difference image DPA and the first infrared image PA with the second infrared image PB as the background image are obtained. In each of the second difference images PB used as the background image, the pattern 52A is offset. In FIG. 5B, the illustration of the first difference image DPA is omitted.

On the other hand, since the image density of the mark 48 portion in the second captured image PB is different from that of the surroundings, the mark 48 appears in the second difference image DPB using the first infrared image PA as the background image. As a result, the determination unit 44 determines that the webbing 14 is not properly mounted. Further, when the mark 48 appears in the second difference image DPB, the determination unit 44 can determine that the webbing 14 worn by the occupant D is twisted on the slip joint 20 side. Moreover, even if the occupant D is wearing the clothes 52 on which the pattern 52A using the infrared absorbing material is formed, the wearing state of the webbing 14 can be properly determined.

As shown in FIG. 5C, when a twist occurs in the middle portion of the shoulder belt portion 14A of the webbing 14 worn by the occupant D, the shoulder side of the occupant D becomes the surface 50A on which the mark 46 is formed. The waist side of the occupant D is the back surface 50B on which the mark 48 is formed. Therefore, the mark 46 of the webbing 14 absorbs the first infrared IrA emitted from the illuminator 32A, and the mark 48 of the webbing 14 absorbs the second infrared IrB emitted from the illuminator 32B. Further, when the garment 54 of the occupant D has the infrared absorption characteristic, each of the first infrared IrA irradiated from the illuminator 32A and the second infrared IrB irradiated from the illuminator 32B is absorbed by the garment 54.

As a result, in each of the first infrared image PA imaged using the first infrared IrA and the second infrared image PB imaged using the second infrared IrB, the image densities are in the clothes 54 and around the clothes 54. (Brightness of the image) is different. Further, in the first infrared image PA imaged using the first infrared IrA, the image densities are similar between the mark 48 portion and the portion other than the mark 48, but the second infrared image IrB imaged using the second infrared IrB. In the infrared image PB, the image density (brightness of the second infrared IrB) is different between the portion of the mark 48 and the portion other than the mark 48.

Therefore, in each of the first infrared image PB and the second infrared image PB, the image density of the clothing 54 is different from the surroundings, so that the clothing 54 portion is offset in each of the first difference image DPA and the second difference image DPB. .. Further, a mark 46 appears on the shoulder side portion of the occupant D on the first difference image DPA, and a mark 48 appears on the waist side portion of the occupant D on the second difference image DPA.

In the determination unit 44, the mark 46 appears on the shoulder side of the occupant D in the first difference image DPA, but the mark 46 does not appear on the waist side of the occupant D, so that the mark 46 is properly set. Assuming that it does not appear, it is determined that the mounting state of the webbing 14 of the occupant D is not appropriate. Further, in the determination unit 44, the mark 46 appears in the first difference image DPA and the mark 48 appears in the second difference image DPB, so that it can be determined that the webbing 14 is twisted in the shoulder belt unit 14A.

In FIG. 4, if the webbing wearing state of the occupant D is appropriate, an affirmative determination is made in step 110 and the process proceeds to step 112, and a webbing wearing detection indicating that the webbing wearing state of the occupant D is appropriate is output.

If the webbing mounting state of the occupant D is not appropriate, a negative determination is made in step 110 and the process proceeds to step 114. In this step 114, a webbing non-attachment detection indicating that the webbing attachment state of the occupant D is not properly output is output.

In FIG. 4, when the webbing mounting state of the occupant D is appropriate, the mounting detection process ends. Further, when the webbing wearing state of the occupant D is not appropriate (webbing is not worn), the wearing detection process is repeated at predetermined time intervals.

An example of the output destination of the wearing detection device 30 in the webbing wearing state is the seatbelt device 10. When the seatbelt device 10 receives the webbing non-wearing detection of the occupant D from the wearing detection device 30, the seatbelt device 10 requests the vehicle side to turn on the seatbelt non-wearing warning lamp (not shown) provided on the instrument panel 28. .. Further, the seatbelt device 10 may request the vehicle side to ring the webbing buzzer without a seatbelt. As a result, the seatbelt non-wearing warning lamp lights up or blinks on the instrument panel 28, or the seatbelt non-wearing warning buzzer sounds, so that the occupant D can be urged to properly fasten the webbing 14.

Further, when the seatbelt device 10 receives the webbing 14 wearing detection of the occupant D from the wearing detection device 30, the seatbelt device 10 requests the vehicle side to turn off the seatbelt non-wearing warning lamp and stop the seatbelt non-wearing warning buzzer.

As a result, in the seatbelt device 10, the wearing state of the webbing 14 of the occupant D can be detected by the wearing detection device 30, so that, for example, the buckle switch for detecting the engagement between the buckle 24 and the tongue 26 in the buckle device 18 can be omitted. .. Moreover, the seatbelt device 10 can detect the illegal attachment of the webbing 14 in which the webbing 14 is not properly attached even though the buckle switch is turned on.

Further, in the vehicle, by using the detection result of the wearing detection device 30, for example, when the occupant D is not in the proper webbing wearing state, the running start can limit the running speed and the like.

Further, in the detection controller 36, when it is detected that the webbing is not attached, the occupant D is not wearing the webbing 14, the slip joint 20 side of the webbing 14 is twisted, or the shoulder belt portion 14A is twisted. Can detect if it is. Therefore, by notifying the occupant D of the non-webbing state caused by the twist of the webbing 14 (for example, announcing), it is possible to urge the occupant D to return the twist generated in the webbing 14 and bring the webbing 14 into an appropriate wearing state. ..

As described above, in the mounting detection device 30, the first infrared IrA and the second infrared IrB having a wavelength different from that of the first infrared IrA are used, and a mark 46 for absorbing the first infrared IrA is provided on the surface 50A of the webbing 14. ing. Further, the mounting detection device 30 captures the reflected light of the first infrared IrA and the second infrared IrB, and determines the webbing mounting state from the captured image. As a result, the webbing wearing state can be accurately detected regardless of the material of the occupant D's clothing, the pattern of the clothing, and the like. Moreover, since the wearing detection device 30 uses the first infrared Ir and the second infrared IrB having different wavelengths, the webbing is performed even if the occupant D wears clothes 52 and 54 having light absorption characteristics in the infrared region. The wearing state can be detected accurately.

Further, a mark 48 for absorbing the second infrared IrB is provided on the back surface 50B of the webbing 14. As a result, the mounting detection device 30 can accurately detect whether or not the webbing 14 mounted by the occupant D is twisted.

Further, in the mounting detection device 30, the first infrared image PA obtained by imaging the reflected light of the first infrared IrA and the second infrared image PB obtained by imaging the reflected light of the second infrared IrB are obtained. The difference image DPA and the second difference image DPA are generated to detect the webbing wearing state. As a result, the wearing detection device 30 can detect the twist of the webbing 14 even if the webbing 14 is twisted in the shoulder belt portion 14A.

On the other hand, in the mounting detection device 30 of the present embodiment, the reflected light of the first infrared ray IrA is imaged by the illuminating device 32A and the camera 34A, and the reflected light of the second infrared ray IrB is imaged by the illuminating device 32B and the camera 34B. However, as at least one of the captured image of the first infrared ray and the captured image of the second infrared ray, the captured image of another device or system provided in the vehicle may be used.

When the vehicle is equipped with a driver monitor system that captures the reflected light of infrared rays, the wearing state detection device is connected to the driver monitor system and captures one of the first infrared rays and the second infrared rays from the driver monitor system. You may get it. Further, the mounting state detection device may be incorporated in the driver monitor system. FIG. 6 shows a schematic configuration of a driver monitor system 62 provided with a mounting detection unit 60 that constitutes a detection means in the mounting state detection device in a block diagram.

As shown in FIG. 6, the driver monitor system 62 is provided with an illuminator 32, a camera 34, and a monitor ECU 64, and the illuminator 32 and the camera 34 are connected to the monitor ECU 64. The monitor ECU 64 is formed with an image pickup control unit 66 instead of the image pickup control unit 38, and a mounting detection unit 60 and a driver monitor unit 68. The mounting detection unit 60 is formed with an image processing unit 40 and a difference image. A generation unit 42 and a determination unit 44 are formed.

The monitor ECU 64 includes a microcomputer (not shown) in which a CPU, a ROM, a RAM, a non-volatile storage, and an input / output interface are connected by a bus. In the monitor ECU 64, the CPU reads a predetermined program stored in the ROM and the storage and executes it while expanding the program in the RAM, so that the image pickup control unit 66, the driver monitor unit 68, and the mounting detection unit 60 (image processing unit 40, difference) are executed. Each function as the image generation unit 42 and the determination unit 44) is realized.

The illuminator 32 irradiates the first infrared IrA and the second infrared IrB toward the occupant D as a driver who is seated in the seat 12. The camera 34 is provided with an infrared transmissive filter, and the camera 34 is an infrared Ir (first infrared IrA and second infrared IrA) reflected from the upper body including the head (face portion) of the occupant seated in the seat 12. IrB) is imaged.

The image pickup control unit 66 captures the reflected infrared light used by the driver monitor unit 68 and the mounting detection unit 60 by controlling the light emission of the illuminator 32 and the image pickup of the camera 34. The driver monitor unit 68 uses a captured image captured by one of the first infrared IrA and the second infrared IrB (for example, the second infrared IrB). Further, the mounting detection unit 60 uses captured images captured by the first infrared IrA and the second infrared IrB.

The imaging control unit 66 performs imaging using the second infrared IrB at preset intervals (time intervals) and the like. The driver monitor unit 68 uses a photographed image using the second infrared IrB to extract preset feature points of each part from the image of the head (face) of the occupant D, and assigns the feature points to each of the extracted feature points. Based on this, the state diagnosis of the occupant D, which determines the state of the occupant D including the orientation of the face of the occupant D, is performed.

As the condition diagnosis of the occupant D, various conditions of the occupant D such as whether or not the occupant D is looking aside by determining the direction of the face of the occupant D and whether or not the physical condition of the occupant D can concentrate on driving are determined. Can be applied. Further, the driver monitor unit 68 can apply various methods for diagnosing the state of the occupant D.

On the other hand, the mounting detection unit 60 requests imaging using the first infrared IrA at a timing set to detect the webbing mounting state of the occupant D. As a result, the image pickup control unit 66 performs the image pickup using the first infrared ray IrA during the image pickup using the second infrared ray IrB.

The mounting detection unit 60 captures the captured image captured by using the first infrared IrA and the captured image captured by using the second infrared IrB for the driver monitor unit 68, and mounts the webbing of the occupant D. Determine the status.

In this way, in the driver monitor system 62, the mounting detection unit 60 is formed in the monitor ECU 64, and the driver monitor unit 68 is provided with an irradiation means that emits infrared rays having a wavelength different from that of the infrared rays, so that the occupant D is mounted on the webbing. The state can be detected accurately. As a result, the number of parts and the cost for detecting the webbing mounting state of the occupant D can be suppressed.

In this embodiment and the modified example, the light absorption characteristic is applied as the optical characteristic to each of the marks 46 and 48. However, a light reflecting member having a light reflecting characteristic as an optical characteristic may be applied to the first optical characteristic unit and the second optical characteristic unit. In this case, a light reflecting member having a wavelength of the peak of the light reflection characteristic similar to the wavelength of the first infrared ray is applied to the first optical characteristic portion, and the wavelength of the peak of the light reflection characteristic is applied to the second optical characteristic portion. A light reflecting member having the same wavelength as that of the second infrared ray may be applied.

FIG. 7 shows FIG. 5 (C) in a state where the mark 46A as the first optical characteristic portion is arranged on the front surface 50A and the mark 48A as the second optical characteristic portion is provided on the back surface 50B in the shoulder belt portion 14A of the webbing 14. ), Each of the images is schematically shown. In FIG. 6, a material having a property of reflecting infrared rays is used on substantially the entire (at least the front surface) of the clothing 54A of the occupant D.

The mark 46A strongly reflects the first infrared IrA emitted from the illuminator 32A, and the mark 48 strongly reflects the second infrared IrB emitted from the illuminator 32B. As a result, in the first infrared image PA, the portion of the mark 46A becomes brighter (blacker) than the periphery (for example, the portion of the mark 48A), and in the second infrared image PB, the portion of the mark 48A is the periphery (for example, the mark 46A). It becomes brighter than the part). As a result, the mark 46A can be properly discriminated in the first difference image DPA, and the mark 48A can be properly discriminated in the second difference image DPB.

Here, the clothes 54A of the irradiation occupant D has a reflection characteristic for infrared rays, so that the clothes 54A appear bright as the mark 46A in the first infrared image PA and as bright as the mark 48A in the second infrared image PB. appear. Therefore, the background image is subtracted from the first infrared image PB with the second infrared image PB as the background image and the background image subtracted from the first infrared image PA, and the first infrared image PA as the background image. In each of the second differential image DPBs, the clothing 54A is offset.

As a result, the mark 46A appears in the first difference image DPA at the portion where the mark 46A of the webbing 14 is on the front side. Further, in the portion where the mark 48A of the webbing 14 is on the front side, the mark 48A appears in the second difference image DPB.

Therefore, even when the mark 46A in which the peak wavelength in the reflection characteristic is the same as the wavelength of the first infrared IrA and the mark 48A in which the peak wavelength in the reflection characteristic is the same as the wavelength of the second infrared IrB are used, the occupant D The webbing wearing state can be properly determined. Moreover, even if the occupant D wears a garment 54A made of a material that reflects infrared rays and there is a portion that reflects infrared rays around the webbing 14, the webbing wearing state of the occupant D can be appropriately determined.

In the present embodiment and modifications described above, the marks 46, 46A as the first optical characteristic unit that reflects or absorbs the first infrared IrA on the webbing 14, and the second optical that absorbs or reflects the second infrared IrB. Marks 48 and 48A are provided as characteristic parts. However, the webbing need only be provided with a first optical characteristic portion at least on the surface (the surface opposite to the occupant in the proper mounting state of the webbing), whereby at least the occupant is properly wearing the webbing. It can detect whether it is in a state or not.

10 ... Seatbelt device, 14 ... Webbing, 30, 60 ... Wearing detection device (wearing state detection device), 32 (32A, 32B) ... Illuminator (irradiation means), 34 (34A, 34B) ... camera (imaging means), 36 ... detection controller (detection means), 46, 46A ... mark (first optical characteristic unit), 48, 48A ... mark (second optical characteristic unit) ), 60 ... Wearing detection unit (detection means).

Claims (3)

Irradiation means for irradiating each of the first infrared rays and the second infrared rays having different wavelengths from the front of the seat on which the occupant sits toward the seat, and
In the webbing of the seatbelt device, the first optical characteristic is provided on the front surface when the occupant seated in the seat is worn, and the peak wavelength of the optical characteristic of light absorption or light reflection is the wavelength of the first infrared ray. Department and
An imaging means that images each of the first infrared ray and the second infrared ray that are irradiated and reflected from the irradiation means from the front of the seat.
A detection means for detecting the wearing state of the webbing of the occupant seated in the seat from the difference image between the photographed image of the first infrared ray and the photographed image of the second infrared ray.
A mounting state detection device equipped with. The second optical is provided on the surface of the webbing opposite to the first optical characteristic portion, and the wavelength of the peak of the optical characteristic corresponding to the optical characteristic of the first optical characteristic portion is the wavelength of the second infrared ray. The mounting state detection device according to claim 1, which includes a characteristic unit. The detection means subtracts the captured image of the first infrared ray from the captured image of the first infrared ray and the captured image of the second infrared ray as the difference image. The mounting state detection device according to claim 2, wherein the mounting state of the webbing is detected by using the second difference image.

Images