JP2001331790A - Crew detecting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a crew detecting system which is simple in structure, reliable and capable of detecting the presence/absence and the seating state of a screw speedily and precisely. SOLUTION: In a crew detection system 10, a circular template is used in a crew detection computer 20 and a circular part on image data of an assistant driver's seat 52 picked up by a CCD camera 12 is extracted. Based on the size and the position of this circular part, the position of the head 72 of the crew 70 in a vehicle 50 is detected. Since the head 72 of the crew 70 keeps a circle though the posture of the crew 70 is changed, the position of the head 72 of the crew 70 is detected speedily and precisely by extracting the circular part directly from the image data. When plural circular parts are extracted, one circular part of the highest propriety corresponding to the head 72 of the crew 70 is specified based on the sizes and positions of the circular parts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an occupant detection system for detecting the presence and absence of an occupant in a vehicle.

[0002]

2. Description of the Related Art As an airbag device, not only an airbag device of a type in which a bag is deployed in front of an occupant seated in a driver's seat, but also a front and side of a passenger seat provided on the side of the driver's seat. A so-called passenger airbag device, a side-impact airbag device, and the like, in which the bag body is deployed by the user, have been devised.

By the way, for example, regarding the above-described passenger airbag device, it is better not to operate the airbag device when there is no occupant in the passenger seat or depending on the physique or sitting posture of the occupant sitting in the passenger seat. The case is conceivable. Further, for example, an airbag device for a passenger seat is generally provided on an instrument panel (dashboard) in front of a passenger seat. However, depending on a distance between an occupant seated on a seat and the instrument panel, the airbag device may be provided. There may be cases where it is better not to operate.

Here, as a method of determining whether or not the airbag device can be operated, there are a method using a load sensor and a method using image processing.

In the method using a load sensor, a load sensor array is built in the seat surface, and the presence or absence of an occupant and an abnormal posture are detected by obtaining a load distribution to determine whether the airbag is activated. However, in such a conventional method, since the sensor is directly subjected to a load, the detection accuracy may not be maintained due to aging, hardening at a low temperature, or an external destruction factor (such as immersion of a beverage). There was a problem.

In the method using image processing, a CCD is used.
Preprocessing such as edge processing is performed on an image captured by a camera or the like, and the presence or absence of an occupant and the seating state are detected based on the image data to determine whether the airbag is activated.
However, in such a conventional method, since the shape of the occupant projected on the image changes due to the change in the occupant's posture, it is difficult to directly detect the seating position of the occupant,
There is a problem that the processing program and the like become complicated and the processing time is long.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above facts, and has as its object to provide an occupant detection system having a simple structure, high reliability, and capable of determining the presence or absence of an occupant and a seating state quickly and accurately. Is the purpose.

[0008]

In order to achieve the above object, an occupant detection system according to the first aspect of the present invention uses an imaging means provided in a vehicle cabin and a circular template having a predetermined size. A circular portion corresponding to the circular template on the image data in the vehicle interior based on the image captured by the imaging unit is extracted, and the position of the occupant's head in the vehicle interior can be detected based on the extraction result. And processing means.

In the occupant detection system according to the first aspect of the invention, for example, when the occupant in the passenger seat is detected by the imaging means arranged near the map lamp in the vehicle, the image on the passenger seat is captured by the imaging means. Is done. The captured image is output to the processing means as image data.

In the processing means to which the image data has been inputted, a circular portion corresponding to the circular template on the image data is extracted using a circular template of a predetermined size. If no circular portion is extracted on the image data, it is detected that no occupant is present on the passenger seat (vehicle compartment). On the other hand, when a circular portion is extracted on the image data, the position of the circular portion on the image data (for example, the center position of the circle on the coordinates stored in advance in the processing means corresponding to the imaging range) is detected. You. Further, when the position of the circular portion on the image data is detected, the processing means detects the position of the occupant's head in the vehicle interior (the position where the occupant is present) based on the detected position.

Therefore, for example, if the detection result is output to the airbag ECU, the airbag EC
At U, it is determined whether or not the airbag device can be operated based on the input signal.

Here, the shape of the head of the occupant in the image data is maintained in a high correlation with the circular template even if the head is moved due to a change in the posture of the occupant. By extracting and detecting the position, the position of the occupant's head can be detected. In particular, when the imaging means is disposed obliquely above the occupant near the map lamp or the like, the correlation between the occupant's head and the circular template is higher, so that the position of the occupant's head is detected more effectively. be able to.

Therefore, by detecting the occupant's head that keeps a circular shape even when the occupant's posture changes, the processing time is short, and the occupant can be detected with high accuracy.

Further, since the imaging means and the processing means are not in contact with the occupant or the like and do not utilize physical deformation, there is a low possibility of deterioration over time, hardening at low temperatures, and a decrease in detection accuracy due to external destruction factors. .

As described above, the occupant detection system according to the first aspect has a simple structure and high reliability, and can quickly and accurately determine the presence or absence of the occupant and the seating state.

The occupant detection system according to a second aspect of the present invention is the occupant detection system according to the first aspect, wherein the processing means can use a plurality of circular templates having different sizes. When a plurality of circular portions are extracted on the image data, the occupant of the occupant is compared by comparing the plurality of circular portions based on the position of each circular portion on the image data and the size of the template used for detection. One circular part corresponding to the head can be specified,
When the identification is performed, a comparison unit that outputs the identification result to the processing unit is provided.

In the occupant detection system according to the second aspect, since the processing means uses a plurality of circular templates having different sizes, all the circular portions on the image data corresponding to these circular templates are extracted. Thus, when a plurality of circular portions exist on the image data, the positions of the plurality of circular portions on the image data (hereinafter, referred to as position data) are respectively detected. The plurality of detected position data and the data of the size of each circular template used for extraction (hereinafter referred to as size data) are transferred to the comparing means.

In the comparing means to which the plurality of position data and the size data have been transferred, one circular portion corresponding to the head of the occupant is determined by comparing a plurality of circular portions based on each position data and size data. Specified. That is,
Of the plurality of extracted circular portions, the size of the circular portion at the extraction position on the image data is most appropriate for the size of the circular portion when the occupant's head is imaged at that position. One tall circular portion is identified as a circle corresponding to the occupant's head.

When one circular portion is specified, the specified result is output to the processing means. In the processing means, the position of the head of the occupant in the vehicle interior is detected based on the position and size of the one specified circular portion.

Therefore, a method of extracting only a corresponding circular portion by using one circular template having a fixed size, or using a plurality of circular templates, but each time a circular portion is extracted, the size of the circular portion is increased. Like the method of determining whether or not the circular portion corresponds to the head of the occupant based solely on the change in the size of the circular portion due to a change in the distance of the occupant's head to the imaging means. There is no. Also, do not compare each circular portion as in the method of determining whether or not the circular portion corresponds to the head of the occupant based on the position and size of the circular portion each time each circular portion is extracted. (For example, if the first extracted circular portion is erroneously specified as corresponding to the occupant's head, and the subsequent processing proceeds, all circular portions are present despite the presence of the circular portion corresponding to the occupant's head. Is determined not to correspond to the occupant's head).

As described above, the occupant detection system according to the second aspect has a simple structure and higher reliability, and can quickly and accurately determine the presence / absence of the occupant and the seating state.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG.

FIG. 1 is a perspective view and a block diagram showing a part of a vehicle 50 to which an occupant detection system 10 according to an embodiment of the present invention is applied. The occupant detection system 10 applied to the vehicle 50 is configured to detect the presence or absence of an occupant on the passenger seat 52 and the seating state.

Here, the occupant detection system 10 includes a CCD camera 12 as imaging means. As shown in FIG. 1, the CCD camera 12 has a map lamp 5 provided at the front end of a roof 54 of the vehicle 50 and at the center in the left-right direction.
6, it is arranged facing the passenger seat 52. Thus, the CCD camera 12 captures an image of the passenger seat 52 from obliquely above.

The CCD camera 12 is electrically connected to an occupant detection computer 20 which constitutes processing means and comparison means. Thus, the image data captured by the CCD camera 12 is transmitted to the occupant detection computer 20.

The occupant detection computer 20 is arranged at an appropriate position on the vehicle 50 and has a storage device (ROM) (not shown). The ROM is provided with coordinate data (hereinafter simply referred to as coordinate data) corresponding to the imaging range of the CCD camera 12 and a plurality of circular templates having different sizes.
By extracting a circular portion on the image data transmitted from the CD camera 12 and detecting its position and size, the vehicle 50
A template matching program 24 for detecting the position of the occupant's head in the vehicle, a comparison program for comparing a plurality of circular portions extracted by the template matching program and identifying one circular portion corresponding to the occupant's head 26. Judgment to determine the seating state of the occupant 70 based on the detection result of the occupant's head position (seating position) in the vehicle 50 by the template matching program, and to output an operation rejection signal to an airbag ECU 30 described later in a predetermined case A program 28 and an occupant detection program 22 for controlling the CCD camera 12 while integrating and executing the programs are stored (see FIG. 2). Further, the occupant detection computer 20 includes a CPU (not shown) for executing the above-described programs.

As shown in FIG. 1, the occupant detection computer 20 is electrically connected to a CPU 32 that constitutes an airbag ECU 30 installed at an appropriate position in the vehicle 50. A signal corresponding to the determination result is output to the CPU 32.

The CPU 32 of the airbag ECU 30
Are electrically connected to the front collision sensor 34 and the side collision sensors 36 and 38 provided on the left and right sides of the vehicle 50.
The front collision sensor 34 and each of the side collision sensors 36 and 38 are configured to transmit a detection signal to the CPU 32 when detecting a deceleration or a load that is equal to or more than a predetermined value. Further, the CPU 32 of the airbag ECU 30 is
It is also electrically connected to an activation device 40 provided in 30. Thereby, basically, each sensor 34, 36,
CPU 32 that has received the detection signal from
0 is activated.

The starting device 40 includes an ignition device 42 for the driver's seat front airbag device, an ignition device 44 for the driver's seat side airbag device, an ignition device 46 for the front passenger seat airbag device, Ignition device 48 for airbag device for seat side collision
Is electrically connected to Each ignition device 42, 44, 4
6, 48 can be individually operated by the activation device 40, and ignites the igniting agent provided in each airbag device. Thereby, each ignition device ignites the igniting agent, so that the gas generating agents respectively housed in the inflators (not shown) of each airbag device are burned, and a large amount of gas is instantaneously generated. . Further, bags (not shown) are disposed in a folded state at predetermined positions near the inflator of each airbag device, and each bag is inflated by the pressure of gas generated by each inflator to expand in front of the occupant 70. , At a predetermined position such as the side.

Next, the operation of the present embodiment will be described with reference to the flowchart of the occupant detection program shown in FIG.

The occupant detection system 10, for example, inserts an ignition key into a key cylinder, and when an accessory (for example, audio or power window) of the vehicle 50 is operable or the engine is started, the occupant detection system 10 The detection computer 20 is activated to activate the occupant detection program 22 previously stored in the occupant detection computer 20, and the occupant detection computer 20 makes the CCD camera 12 operable.

In the occupant detection computer 20 in which the occupant detection program 22 is activated, first, in step 102, an image pickup signal is output to the CCD camera 12. When this imaging signal is input to the CCD camera 12, the CCD camera 1
2 captures an image on the passenger seat 52. CCD camera 12
Performs image capturing, the image on the passenger seat 52 is read as image data in step 104.

When the image data is read, step 10
At 6, the template matching program 24 is operated, and one circular template to be used is selected from a plurality of circular templates having different sizes. When the circular template is selected, in step 108, the circular template is moved up, down, left, and right on the image data, thereby extracting a corresponding circular portion on the image data.

As a result of the work of extracting the circular portion, in step 110, it is determined whether or not a circular portion corresponding to the circular template used in step 106 has been extracted. If it is determined in step 110 that the circular portion has been extracted, the size of the circular template used in step 112 and the center position on the coordinate data of the extracted circular portion (hereinafter referred to as circular data) are stored. ,
Proceed to step 114. On the other hand, if it is determined in step 110 that the circular portion has not been extracted, step 112
And the process proceeds to step 114 as it is.

In step 114, it is determined whether or not there is another circular template which is set in the template matching program in advance and is not used. If it is determined that there is another circular template, the process returns to step 106,
The above series of operations is repeated. On the other hand, when it is determined that there is no other circular template (all the set circular templates have been used), the process proceeds to step 116.

In step 116, it is determined whether or not the circular data is stored in step 112. If it is determined that the circular data has not been stored, the process proceeds to step 126 of the determination program 28 described later. on the other hand,
If it is determined that the circular data is stored, step 11
Proceeding to 8, it is determined whether or not the number of circular data stored in step 118 is one. If it is determined that the number of the stored circular data is one, step 12 is performed as it is.
Go to 0. On the other hand, if it is determined that there are a plurality of stored circular data, the process proceeds to step 128 of the comparison program 26, which will be described later.
After one circular portion is identified in step 12
Go to 0.

In step 120, the transferred circular data (only one circular data stored in step 112, or the center position on the coordinate data of the circular portion specified only in step 130 and the used circular template Based on the size, the head position (seating position) of the occupant in the vehicle 50 is detected, and the template matching program 24 ends.

When the head position of the occupant is detected, the determination program is operated in step 122, and the seating state of the occupant is determined based on the head position of the occupant in the vehicle 50.

When the seating state of the occupant 70 is determined, it is determined in step 124 whether or not each of the airbag devices for the passenger seat is operable. That is, it is determined whether or not the operation of the ignition device 46 of the front passenger seat airbag device and the activation of the ignition device 48 of the front passenger seat airbag device should be prohibited. When it is determined that both the ignition device 46 of the front passenger seat airbag device and the ignition device 48 of the front passenger seat airbag device should not be prohibited from operating, the determination program 2
8 is terminated as it is and the occupant detection program 22
Is also terminated.

On the other hand, the ignition device 46 of the front seat airbag device and the ignition device 4 of the front passenger seat airbag device
If it is determined that one or both of the operations of the airbag device 8 should be prohibited, the process proceeds to step 126, and an operation rejection signal corresponding to the airbag device whose operation is to be prohibited is output to the airbag ECU 30. . If it is determined in step 116 that the circular portion is not stored, it is determined that the occupant 70 does not exist on the passenger seat 52.
An operation rejection signal for both the ignition device 6 and the ignition device 48 of the passenger side collision airbag device is output to the airbag computer 30. When the operation rejection signal is output in step 126, the determination program 28 ends and the occupant detection program 22 ends.

The operation of the comparison program 26 when it is determined in step 118 that a plurality of circular portions have been stored will be described.

In step 128, the comparison program 26
Is operated, and the size at the center position (center position on the coordinate data) of each of the plurality of stored circular portions (the size of the circular template used for extracting the circular portions)
Are compared. When each circular part is compared, step 1
At 30, one circular portion corresponding to the head of the occupant is specified based on the comparison result. In other words, the size of the circular portion at the center position on coordinate data (the extracted position on the image data) of the extracted circular portions among the stored circular portions is the position of the occupant's head. One circular part having the highest validity corresponding to the size of the circular part when the part is imaged is specified as a circle corresponding to the head of the occupant. When the head of the occupant is specified, the comparison program 26 is terminated, and as described above, step 120 of the template matching program 24 is executed.
Proceed to.

Here, an example of extraction of a circular portion on image data and comparison of the circular portion will be described with reference to FIG.

FIG. 3 shows a passenger seat 52 using the CCD camera 12.
The image data 80 obtained by capturing the upper part is shown as an example. On this image data 80, images of the occupant 70 sitting on the passenger seat 52 and its head 72, the roof 54, the instrument panel 58, the door 60, the A pillar 62, the center pillar 64, the seat belt 66, etc. Is projected.

Based on the image data 80, step 106 of the above-described template matching program 24 is executed.
In step 114, a circular portion is extracted.

That is, after the circular template A is selected in step 106, the circular template A is extracted on the image data 80 by moving the circular template A up, down, left and right in step 108. As a result, a circular portion corresponding to the circular template A is extracted at the left end of the image data 80 at the center in the vertical direction.
At 12, the circular data of the circular portion (the center position on the image data 80 and the size of the circular template A used) are stored.

In step 114, it is determined that there is another circular template, and the process returns to step 106. When circular template B is selected in step 106, the circular template B is moved up, down, left, and right on the image data 80. Perform circular part extraction. As a result, in step 108, a circular portion corresponding to the template B is extracted at the lower end of the image data 80 at the center in the left-right direction,
In step 112, the circular data of the circular portion is stored.

After all, in the example of FIG. 3, two circular data corresponding to the two circular templates are stored, and these circular data are transferred to the comparison program 26. A comparison is made based on the center position above and the size of each of the templates A and B.
One circular portion corresponding to 2 is specified.

As described above, the circular portion corresponding to the circular template A is located at the left end of the image data 80 at the center in the vertical direction, and the circular portion corresponding to the circular template B is located at the lower end of the image data 80 at the center in the horizontal direction. positioned. Here, since the CCD camera 12 is disposed in the map lamp 56 (see FIG. 1), it is known that the images projected to the left and above the image data 80 are farther away from the CCD camera 12. . Therefore, step 128
In the comparison, the circular portion corresponding to the circular template A has an appropriate size with respect to the distance to the CCD camera 12 and the position thereof is appropriate, while the circular portion corresponding to the circular template B has the same size as the CCD camera 12. Is small in spite of the short distance. From this comparison result, since the circular portion corresponding to the circular template A has the highest validity corresponding to the head 72 of the occupant 70,
In step 130, one circular portion corresponding to the circular template A is specified, and the process proceeds to step 120 of the template matching program 24.

Further, after the position of the head 72 of the occupant 70 in the vehicle 50 is specified in Step 120 based on the circular data of one circular portion corresponding to the circular template A, Step 122 of the determination program 28 Is used to determine the sitting state of the occupant 70. In the case of this example, it is determined that the occupant 70 is normally seated, and it is determined in step 124 that it is not necessary to output the operation rejection signal to the airbag device. Thus, the determination program 28 is terminated and the occupant detection program 22 is terminated.

In the present embodiment, the occupant detection system 10 is configured to detect the presence or absence of the occupant 70 on the passenger seat 52 and the seating state. However, the present invention is not limited to this. The configuration may be such that the presence or absence of the occupant of the seat and the seating state are detected, and the detection result may be provided to the operation and prohibition of the operation of the airbag device for the driver's seat or the operation and prohibition of the operation of other devices. Further, the occupant detection system may be applied to a part or all of the driver seat, the passenger seat, and the rear seat of the vehicle 50 at the same time. In this case, for example, CCD
It is also possible to widen the imaging range of the camera or add a swing mechanism so that one CCD camera and an occupant detection computer can detect occupants in a plurality of seats.

In the present embodiment, the CCD camera 1
2 is arranged in the map lamp 56, but the present invention is not limited to this. For example, it may be arranged in the upper end of the A pillar 62 or in the vicinity of the sun visor. Note that C
It is desirable that the CD camera 12 is disposed with the imaging range fixed obliquely above the occupant to be detected. Further, the imaging means is not limited to a CCD camera, and may be, for example, a vidicon or a CMOS camera.

Further, in the present embodiment, template matching is performed using raw image data. However, the present invention is not limited to this. For example, before performing template matching, pre-processing of image data may be performed. Edge processing or the like may be performed.

Furthermore, in this embodiment, the seating state of the occupant 70 is determined in step 122, but this is omitted, and the airbag device is directly detected from the position of the head 72 of the occupant 70 in the vehicle 50. It is good also as a structure which judges whether the operation | movement of is possible. With this configuration, the occupant detection computer can be simplified, and is effective when data on the seated state such as the occupant's posture is not required (for example, when only determination of whether or not the airbag device is operable is performed).

As described above, the occupant detection system 10 according to the present embodiment has high reliability, and can quickly and accurately determine the presence or absence of the occupant and the seating state. In particular, since the head of the occupant maintaining the circular portion is directly detected even when the occupant's posture changes, the processing time is short and highly accurate occupant detection is possible.

[0056]

As described above, the occupant detection system according to the present invention has high reliability and can quickly and accurately determine the presence / absence of an occupant and the seated state.

[Brief description of the drawings]

FIG. 1 is a perspective view and a block diagram showing a part inside a vehicle to which an occupant detection system according to an embodiment of the present invention is applied.

FIG. 2 is a flowchart of an occupant detection program in the occupant detection system according to the embodiment of the present invention.

FIG. 3 is a plan projection view on a passenger seat showing an example of extraction of a circular portion on image data in the occupant detection system according to the embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 10 occupant detection system 12 CCD camera (imaging means) 20 occupant detection computer (processing means, comparing means) 24 template matching program (processing means) 26 comparison program (comparing means) 30 airbag computer 50 vehicle 52 passenger seat 56 map lamp 70 Crew 80 image data

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Seiwa Otaki 3-260 Toyota, Oguchi-cho, Niwa-gun, Aichi Prefecture F-term in Tokai Rika Electric Works, Ltd. (Reference) 3D054 AA03 AA14 AA21 EE10 EE11 EE14 EE25 EE31 FF16 5B057 AA16 BA02 CA12 CA16 CB18 DC33 5C054 AA05 CA04 CC03 CE11 ED07 FC15 FF07 HA30 5L096 BA02 BA04 CA02 HA08 JA09

Claims (2)

[Claims] An image pickup means provided in a vehicle interior, and a circle corresponding to the circular template on image data in the vehicle interior based on an image taken by the image pickup means using a circular template of a predetermined size. Processing means for extracting a portion and detecting a position of the occupant's head in the vehicle cabin based on the extraction result. 2. The processing means is capable of using a plurality of circular templates having different sizes. When the processing means extracts a plurality of circular portions on the image data, By comparing the plurality of circular portions based on the position of the circular portion and the size of the template used for extraction, it is possible to specify one circular portion corresponding to the head of the occupant. The occupant detection system according to claim 1, further comprising: a comparison unit that outputs the identification result to the processing unit.