WO2005075248A1

WO2005075248A1 - Vehicle mounted monitor

Info

Publication number: WO2005075248A1
Application number: PCT/JP2004/017387
Authority: WO
Inventors: Mitsuyoshi Nagao; Hidenori Sato
Original assignee: Murakami Corporation
Priority date: 2004-02-10
Filing date: 2004-11-24
Publication date: 2005-08-18
Also published as: JP2005225250A

Abstract

A vehicle mounted monitor comprising a lens (21) which can take a first focal length for short distance used for imaging a rain drop adhering to a vehicle, and a second focal length for long distance used for imaging the periphery of the vehicle. A camera section (2) can switch the focal length of the lens (21) between the first focal length and second focal length. A rain drop detecting section (32) detects the presence/absence of a rain drop based on an image taken by the camera section (2) with the first focal length, and a monitoring section (32) monitors the periphery of the vehicle based on an image picked up by the camera section (2) with the second focal length. Since detection of a rain drop and monitoring of the periphery of the vehicle can be carried out by one camera section, the cost and the installation space can be reduced.

Description

In-vehicle monitoring device

Technical field

The present invention relates to an in-vehicle monitoring device applicable to vehicles such as automobiles, and more particularly to an in-vehicle monitoring device for detecting raindrops and monitoring the periphery of the vehicle. Background art

[0002] In recent years, a vehicle-mounted monitoring device using a camera unit having an imaging unit such as a CCD (Charge Coupled Device) has been mounted on vehicles such as automobiles. Conventionally, as such an in-vehicle monitoring device, a device that detects raindrops and a device that monitors the periphery of an automobile are known. The following discloses the related art.

Patent document 1: Japanese Patent Application Laid-Open No. 2001-206201 (paragraphs 0026-0029, FIG. 1, 03) Patent Document 2: Japanese Patent Application Laid-Open No. 2001-153969 (paragraphs 0014-0018, FIG. 1)

Patent Document 3: JP 2001-147278 A (paragraphs 0017—0022, 01)

Patent Document 4: Japanese Patent Application Laid-Open No. 2001-141838 (paragraphs 0013-0017, FIG. 1)

Patent Document 5: JP-A-2000-355260 (paragraphs 0013-0017, 01)

Patent Document 6: JP-A-2002-347517 (paragraphs 0015-0019, FIG. 2)

[0003] Among them, one that detects raindrops, for example, captures an image of a front window (window shield) of an automobile using a camera unit, and uses the image obtained by the camera unit to detect raindrops attached to the front window. Is generally known to be configured to detect According to such a device, it is possible to automatically detect raindrops and to operate a front wiper or the like based on the detection.

[0004] On the other hand, as a device for monitoring the periphery of a vehicle, a configuration is adopted in which a camera unit is used to image the periphery of the vehicle, and an image obtained by the camera unit is used to monitor the periphery of the vehicle. Things are known. According to such an apparatus, an obstacle or the like existing around the automobile can be detected by using the camera unit.

[0005] In the above-mentioned conventional in-vehicle monitoring device, it is possible to detect raindrops and monitor the vicinity of the vehicle based on the image captured by the camera unit. This force In order to have two functions, such as detection of raindrops and monitoring around the car, it was necessary to mount two camera units on the car. This is because the camera used for detecting raindrops needs to set the focal length of the lens closer (short), while the camera used for monitoring surroundings has a longer focal length ( It is necessary to set it longer. Therefore, there is a problem that the cost increases and the space for installing the camera unit is required for two vehicles. The present invention has been made in view of such problems of the related art.

Disclosure of the invention

[0006] An on-vehicle monitoring device as one aspect of the present invention includes a first focal length for a short distance for imaging the surface of a vehicle, and a second focal length for a long distance for imaging the periphery of the vehicle. A camera unit capable of switching the focal length of the lens between the first focal length and the second focal length, and a camera unit capable of switching the focal length of the lens to the first focal length. A raindrop detector that detects whether raindrops are attached to the surface of the vehicle based on an image captured by the camera unit with the focal length set, and a focal length of the lens that is set to the second focus. A monitoring unit that monitors the periphery of the vehicle based on an image captured by the camera unit at a distance.

[0007] According to such an on-vehicle monitoring device, the camera unit captures the first focal length for a short distance for capturing the surface of the vehicle (raindrops attached to it) and the periphery of the vehicle. The lens has a second focal length for a long distance, and by switching the focal length of this lens to the first focal length or the second focal length, the raindrops adhering to the vehicle can be reduced. It is possible to take an image and also to take an image around the vehicle. Therefore, by switching to a desired focal length, one camera section can obtain both the far and near images. Then, the raindrop detection unit detects the presence or absence of raindrops based on the image captured by the camera unit at the first focal length, and the monitoring unit based on the image captured by the camera unit at the second focal length. The surroundings of the vehicle are monitored. In this way, an image necessary for detecting raindrops and monitoring the surroundings of the vehicle can be captured by a single camera unit, and the two functions provided by a single powerful camera unit that were previously impossible An in-vehicle monitoring device is obtained. As a result, low cost daggers can be achieved, and installation space can be reduced. it can.

[0008] The on-vehicle monitoring device may further include a driving unit that switches between the first focal length and the second focal length. Thereby, the switching between the first focal length and the second focal length can be smoothly performed by the driving means.

[0009] The on-vehicle monitoring device including the driving unit further includes a switching control unit that performs switching between the first focal length and the second focal length by the driving unit at predetermined intervals. It may be something. As a result, the detection of raindrops and the monitoring of the surroundings of the vehicle can be automatically performed alternately, so that one of the functions is performed, for example, when the driver or the like forgets to set. It can be prevented from being lost.

[0010] The on-vehicle monitoring device according to another aspect of the present invention includes at least two areas: a short-distance area for imaging the surface of the vehicle and a long-distance area for imaging the periphery of the vehicle. A camera unit that includes a lens having a subject area, and simultaneously captures the two subject areas via the lens; and a camera that captures the short-distance area and the long-distance area from an image captured by the camera unit. A specifying unit that specifies an image, a raindrop detecting unit that detects whether raindrops are attached to the surface of the vehicle based on the image specified as the short-distance area by the specifying unit, A monitoring unit that monitors the periphery of the vehicle based on the image specified as the long-distance area by the specifying unit.

[0011] According to such an in-vehicle monitoring device, the camera unit uses the lens for imaging the short-distance region for imaging the surface of the vehicle (raindrops attached thereto) and the periphery of the vehicle. It has at least two subject areas, one for the long-distance area and the other for the long-distance area. Since the two subject areas are simultaneously imaged via the lens, the short-distance area and the long-distance area The images of and can always be obtained simultaneously by one imaging. Therefore, it is not necessary to provide a special drive mechanism or the like in the camera unit, and the cost can be reduced.

[0012] According to the present invention, the detection of raindrops and the monitoring of the periphery of the vehicle can be performed by a single camera unit, so that cost reduction can be achieved and installation space can be reduced. It is possible to obtain a vehicle-mounted monitoring device that can be used.

[0013] The aspects and advantages of the invention described above, as well as other advantages and further features, are set forth in the detailed description of exemplary and non-limiting embodiments of the invention, described below with reference to the accompanying drawings. A detailed explanation will be even more evident.

Brief Description of Drawings

FIG. 1 is a schematic diagram showing an automobile equipped with an on-vehicle monitoring device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a schematic configuration of a vehicle-mounted monitoring device according to a first embodiment.

FIG. 3 (a) is a perspective view of a camera unit used in a vehicle-mounted monitoring device, and FIG. 3 (b) is a partially omitted cross-sectional view of the camera unit.

FIG. 4 is a time chart showing switching between a wide position and a tele position.

FIG. 5 is a diagram schematically showing an image at a wide position.

FIG. 6 is a diagram schematically showing an image at a telephoto position.

FIG. 7 is a perspective view of a camera unit used in an in-vehicle monitoring device according to a second embodiment of the present invention.

FIG. 8 is a block diagram showing a schematic configuration of a vehicle-mounted monitoring device according to a second embodiment.

FIG. 9 is a diagram schematically showing an image captured by a camera unit of the vehicle-mounted monitoring device according to the second embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description, the same elements will be denoted by the same reference symbols, without redundant description.

[0016] (First embodiment)

An on-vehicle monitoring device according to a first embodiment of the present invention will be described with reference to FIGS. As shown in FIGS. 1 and 2, an in-vehicle monitoring device 1 according to the present embodiment includes a camera unit 2, a control unit 3 that controls the operation of the camera unit 2, and an image captured by the camera unit 2. And a display unit 4 for displaying, based on the image captured by the camera unit 2, detection of raindrops and monitoring of the periphery of the vehicle C (white line detection, etc.) as described later. ! /

As shown in FIG. 1, the camera unit 2 is installed near a stay of an inner mirror (not shown) of a vehicle C such as an automobile, and a lens 21 is provided in front of the vehicle C (front direction: as shown in FIG. 1). To the left). Therefore, the camera unit 2 is configured to capture an image in front of the vehicle C through the front window FW. As shown in FIG. 3 (a), the camera unit 2 incorporates an image pickup device such as a CCD, a focal length control unit 23c described later, and a processing unit 24 (both shown in FIG. 2). A housing 22; a lens 21 provided at the front of the housing 22 and having at least two focal lengths; and a focal length driving unit for switching between the two focal lengths by rotating the lens 21. 23 (drive means).

As shown in FIG. 3 (b), the lens 21 is fixed to the housing 22 and provided with a fixed cylinder 21a having a male screw formed on the outer periphery and an incident lens 21b provided at the tip end. A female screw screwed to the outer periphery of the cylinder 21a has a movable cylinder 21c formed on the inner periphery. Such a moving cylinder 21c is configured to be screwed and attached to the fixed cylinder 21a so that it can advance and retreat in the optical axis direction of the fixed cylinder 21a (vertical direction on the paper surface of FIG. 1) by its own rotation. , At least the first focal length L1 (wide position: the state shown by the solid line in FIG. 3 (b), the same applies hereinafter) and the second focal length L2 (telephoto position: shown by the dashed line in FIG. 3 (b)) (Hereafter the same), two focal lengths can be taken. On the outer periphery of the movable cylinder 21c, a gear portion 21d is formed over the entire periphery, which meshes with a gear portion 23b of a focal length driving portion 23 described later. In addition, a lens group (lens unit) including a lens or a plurality of lenses (not shown) is arranged inside the fixed cylinder 21a and the movable cylinder 21c.

In the present embodiment, at the wide position L1, the front window FW (see FIG. 1) near the front of the lens 21 is set to be in focus, and at the tele position L2, the vehicle C ( (See Fig. 1) so that it is focused in front of other vehicles traveling in front of vehicle C (positions where white lines on the road are projected, etc.). Therefore, at the wide position L1, raindrops adhering to the front window FW (surface of the vehicle C) can be imaged, and at the tele position L2, other vehicles or vehicles traveling ahead of the vehicle C and roads can be photographed. White lines and the like can be imaged.

As shown in FIG. 3 (b), the focal length driving section 23 has a stepping motor 23a serving as a rotation drive source of the moving cylinder 21c, and a gear section 23b driven by the stepping motor 23a. ing. The stepping motor 23a is driven under the control of a focal length control unit 23c (see FIG. 2) provided in the housing 22, and the focal length control unit 23c is connected to the wide position L1 or the wide position L1. The moving cylinder 21c of the lens 21 moves to the telephoto position L2. A signal for driving the stepping motor 23a is transmitted. When the driving of the stepping motor 23a is controlled by the control of the focal length control unit 23c, the moving cylinder 21c of the lens 21 is moved to the wide position L1 or the tele position L2 in accordance with the rotation of the gear unit 21d.

The image captured at the wide position L1 or the telephoto position L2 is sent to the control unit 3 (see FIGS. 1 and 2) after being processed by the processing unit 24 (see FIG. 2) of the camera unit 2. You.

As shown in FIG. 2, the control unit 3 has a switching control unit 31 and an image processing unit 32 (functioning as a raindrop detection unit and a monitoring unit). The switching control unit 31 sends a signal for controlling the imaging to the camera unit 2. Upon receiving the signal from the switching control unit 31, the focal length control unit 23c of the camera unit 2 changes the focal length. The drive of the drive unit 23 is controlled. The control by the control unit 3 is performed in a preset mode, for example, a mode in which the wide position L1 and the tele position L2 are alternately switched at predetermined time intervals as shown in FIG. By performing such control, the switching between the wide position L1 and the tele position L2 is performed automatically and alternately, and the detection of raindrops described later and the monitoring of the periphery of the vehicle C are performed with high reliability. Becomes possible. As the predetermined time interval for the switching, for example, a force that sets the wide position L1 to 1 second and the tele position L2 to 5 seconds can be set as appropriate.

Further, as shown in FIG. 2, the control unit 3 receives an input of an induction switch signal (IG SW signal) 31a and a speed signal 31b as external inputs, and performs control corresponding to these inputs. Has been established. Various modes can be considered as the control related to the induction switch signal 31a. For example, when the engine (not shown) of the vehicle C is stopped, this is detected and the lens 21 of the camera unit 2 is detected only at the wide position L1. Is set to be set. This is because, for example, when the engine is stopped, there is almost no need to monitor the surroundings of the vehicle C. Therefore, by fixing the lens 21 of the camera unit 2 at the wide position L1, detection corresponding to raindrops (linked with detection) Operating an external device such as a wiper). In addition, various modes can be considered as the drive control related to the speed signal 31b.For example, during low-speed running such as slow driving, this is detected and the lens 21 of the camera unit 2 is set only at the wide position L1. Control as described above. This is, for example, When traveling at low speeds, there is almost no need to perform white line detection or the like. Therefore, by fixing the lens 21 of the force camera unit 2 at the wide position L1, detection corresponding to raindrops can be performed smoothly.

[0025] The image processing unit 32 processes an image sent from the camera unit 2, and processes an image captured at the guide position L1 and an image captured at the tele position L2. With two routines. When the lens 21 of the camera unit 2 is set to the wide position L1, image processing for detecting raindrops is performed based on the image captured by the camera unit 2. As the image processing, for example, as shown in FIG. 5, the image including the raindrop R is filtered (average value filter) to remove noise, and at the same time, to extract the edge of the strong edge area on the image. A method of detecting a raindrop R by performing a binary dagger process or the like on the extracted region. It should be noted that various other known techniques can be employed for the image processing related to the detection of the raindrop R.

When the lens 21 of the camera unit 2 is set at the telephoto position L2, as shown in FIG. 6, a white line H on the road is detected based on the image E2 captured by the camera unit 2. Perform image processing to perform. As the image processing, for example, differential processing is performed on the acquired image as shown in FIG. 6 to generate a differential image in which a boundary (Etsu) having a difference in luminance value in a vertical direction or an oblique direction appears. In addition, there is a method of detecting the white line H by performing a process such as searching for an error point. It should be noted that various other known techniques can be employed for image processing related to the detection of the white line H. Further, by detecting the movement of the same point as an optical flow from two consecutive images captured by the camera unit 2, processing such as monitoring the approach of another vehicle CA can be performed.

[0027] The control (mode) by the control unit 3 can be arbitrarily selected by operating an operation switch (not shown), a remote controller, and the like provided around the driver's seat S (see FIG. 1). is there. As a result, it can be used as the in-vehicle monitoring device 1 in a mode or the like according to the driver's preference.

[0028] The display unit 4 is installed at an appropriate position around the driver's seat S (see Fig. 1), and is capable of displaying the images El and E2 (see Figs. 5 and 6). The display unit 4 includes a means for notifying the driver of the detection of raindrop R or the detection of another vehicle CA, such as when detecting the other vehicle CA. For example, it is possible to provide a notifying means by emitting a voice or an alarm sound, or a notifying means such as blinking a display screen (not shown) of the display unit 4. In addition, as such a notification means, in addition to the one provided along with the display unit 4, a notification tool such as a speed or a lamp may be provided at an appropriate position around the driver's seat S.

[0029] Next, the operation of the vehicle-mounted monitoring device 1 will be described with reference to the drawings as appropriate.

First, an ignition switch (not shown) is operated to turn on the induction switch, and an ignition switch signal 31a (see FIG. 2) is sent to the switching control unit 31 of the control unit 3. The device 1 is activated, and the switching control unit 31 of the control unit 3 sends a control signal to the camera unit 2. In this case, when the speed of the vehicle C is a slow speed including a stop state, the speed signal 31b is input to the control unit 3, and the focal length of the lens 21 of the camera unit 2 is set to the wide position L1. A signal is sent from the control unit 3 so as to be set.

Thus, the lens 21 of the camera unit 2 is set at the wide position L1, and the camera unit 2 captures an image for detecting the raindrop R. The captured image is sent to the image processing unit 32 of the control unit 3 via the processing unit 24 of the camera unit 2, and image processing for detecting the raindrop R is performed. When the raindrop R is detected, the driver is notified of the detection by the above-described notification means or the like, and the wiper, the wiper, and the like are operated. In this case, the operating speed of the wiper can be set so as to change depending on the amount of raindrop R detected per unit area.

After that, when the speed of the vehicle C increases, the speed signal 31b is no longer input to the control unit 3, and the switching control unit 31 performs the predetermined mode, for example, the predetermined interval as shown in FIG. Sends a signal so that the camera unit 2 takes a picture in a mode in which the wide position L1 and the tele position L2 are alternately switched. In response to this, the lens 21 of the camera unit 2 moves to the wide position L1 and the tele position L2 (see FIG. 3 (b)), and the images at the respective positions as shown in FIGS. Images are taken at intervals. The captured image is sent from the image processing unit 24 of the camera unit 2 to the image processing unit 32 of the control unit 3, and the image processing unit 32 performs image processing based on each image in a separate routine. You.

[0033] Thus, detection of raindrop R, detection of white line H, and the like (monitoring around vehicle C) are alternately repeated. Then, when the raindrop R is detected, the fact is notified by the notification means or the like. When a diver is notified and the white line H is detected, the information is used to determine, for example, driving conditions (driving situation program processing to avoid dangers, etc.) The results can be reported to the driver, and the trends of other vehicles CA (see Fig. 5) can be monitored and the results can be reported to the driver.

An image captured by the camera unit 2, in particular, an image E 2 (see FIG. 6) at the tele position L 2 (see FIG. 3B) can be displayed on the display unit 4. This allows the driver to check the monitoring status on the display unit 4.

In the present embodiment, as shown in FIG. 1, the camera unit 2 is provided with a force provided in the vicinity of a stay of an inner mirror (not shown) near the front window FW, for example, one of the left and right outer mirrors. Alternatively, it can be provided at both positions, or can be provided at a position where the rear of the vehicle C can be imaged. In this case, the camera units 2 are provided at a plurality of positions, and the images obtained from these units are subjected to image processing so that monitoring around the vehicle C is performed in a complex manner.

[0036] According to such an on-vehicle monitoring device 1, the camera unit 2 includes the short-distance wide position L1 (first focal length) for imaging the raindrop R (see FIG. 5) attached to the vehicle C. , And FIG. 3 (b)), and a lens 21 that can take a long-distance tele position (second focal length) L2 for imaging the periphery of the vehicle C. By switching the distance to the wide position L1 or the tele position L2, it is possible to image the raindrops R attached to the vehicle C (see Fig. 5) and to image the surroundings of the vehicle C (see Fig. 6). Can be. Therefore, by switching to the desired focal length, one camera unit 2 can obtain both the far and near images.

The image processing unit (raindrop detection unit) 32 detects the presence or absence of a raindrop R (see FIG. 5) based on the image captured by the camera unit 2 at the wide position L1. 3), the periphery of the vehicle C is monitored based on the image captured by the camera unit 2 at the tele position L2.

[0038] As described above, an image necessary for detecting the raindrop R and monitoring the periphery of the vehicle C can be captured by the single camera unit 2, and the powerful camera unit 2 that can be realized in the past is not required. An on-vehicle monitoring device 1 having two functions is obtained. With this, it is possible to achieve low cost dani In addition, the installation space can be reduced.

Further, switching between the wide position L 1 and the tele position L 2 can be smoothly performed by the focal length driving unit 23 of the camera unit 2.

Further, switching between the wide position L1 and the tele position L2 by the focal length driving unit 23 can be performed at predetermined time intervals by the switching control unit 31, and the detection of the raindrop R and the monitoring of the periphery of the vehicle C can be performed. It can be done automatically and alternately. As a result, it is possible to prevent one of the functions from being stopped due to, for example, the driver forgetting to set the function. The switching between the wide position L1 and the tele position L2 can also be performed manually.

(Second Embodiment)

An on-vehicle monitoring device according to a second embodiment of the present invention will be described with reference to FIGS. The difference between the vehicle monitoring device 5 of the present embodiment (see FIG. 8) and the first embodiment is that, as shown in FIG. The point is that a bifocal lens that can simultaneously image a body is used.

In FIG. 7, the lens 11 of the camera unit 10 includes a short-distance region K1 for imaging a raindrop R (see FIG. 9) attached to the front window FW of the vehicle C (see FIG. 1), and a vehicle C (see FIG. 9). It has at least two subject regions, a long-distance region K2 for imaging the periphery of (see FIG. 1). As a result, images in the two subject areas can be simultaneously captured by the camera unit 10.

The image captured by the camera unit 10 is sent to the image processing unit 32 of the control unit 3 via the processing unit 24 of the camera unit 10 as shown in FIG. Image processing such as detection of the white line H (both refer to FIG. 9) is performed. In this case, the image sent from the camera unit 10 is one in which both the far and near images are combined into one image (see FIG. 9). That is, the upper half is an image based on the short distance area K1, and the lower half is an image based on the long distance area K2. Image processing based on such an image is generally performed as follows.

First, on the image, the image of the short-distance region K1 and the image of the long-distance region K2 are separated (cut out), and the above-described detection of the raindrop R is performed for each separated image. Image processing for detecting the white line H (monitoring). Snow That is, the detection of the raindrop R is performed based on the image of the short-distance area Kl on the upper half side, and the image processing for monitoring is performed based on the long-distance area K2 on the lower half side. Note that the switching control unit 31 is simplified because it does not require a control circuit for switching between the wide position L1 and the telescopic position L2 as described in the first embodiment.

[0045] According to such a vehicle monitoring device 5, the camera unit 10 has a short-range area (see FIG. 7) in which the lens 11 captures the raindrop R attached to the front window FW of the vehicle C. ) It has at least two object areas K1 and a long-distance area K2 for imaging the periphery of the vehicle C (see Fig. 7), and simultaneously images these two object areas via the lens 11. As a result, the images of the short-distance region K1 and the long-distance region K2 can always be obtained simultaneously by one imaging. Therefore, it is not necessary to provide a special drive mechanism or the like in the camera section 10, and the cost can be reduced. The lens 11 may be provided with three or more object regions. This case can be dealt with by performing image processing for each area.

As described above, the exemplary embodiments of the present invention have been described with reference to the drawings. Various modifications may be made to these embodiments without departing from the spirit and scope of the present invention as defined in the appended claims. Modifications and changes are possible.

Claims

The scope of the claims

[1] A lens which can have a first focal length for a short distance for imaging the surface of a vehicle and a second focal length for a long distance for imaging the periphery of the vehicle, A camera unit capable of switching a focal length of a lens between the first focal length and the second focal length; and an image captured by the camera unit with the focal length of the lens being the first focal length. A raindrop detecting unit that detects whether or not the force of the raindrops adhering to the surface of the vehicle based on the image that

A monitoring unit that monitors the periphery of the vehicle based on an image captured by the camera unit with the focal length of the lens set to the second focal length;

An on-vehicle monitoring device comprising:

2. The in-vehicle monitoring device according to claim 1, further comprising a driving unit configured to switch the focal length of the lens between the first focal length and the second focal length.

3. The vehicle according to claim 2, further comprising a switching control unit that switches the first focal length and the second focal length by the driving unit at a predetermined time interval. Monitoring device.

[4] A lens having at least two subject areas, a short-distance area for imaging the surface of the vehicle and a long-distance area for imaging the periphery of the vehicle, and A camera section for simultaneously capturing two subject areas,

A specifying unit that specifies an image of the short-distance area and the long-distance area from an image captured by the camera unit;

A raindrop detecting unit that detects whether or not the force that the raindrops adhere to the surface of the vehicle based on the image specified as the short-distance area by the specifying unit;

A monitoring unit that monitors the periphery of the vehicle based on the image specified as the long-distance area by the specifying unit;

An on-vehicle monitoring device comprising: