JPH0979847A - On board distance measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure a distance with fixed accuracy regardless of the distance to an object by setting the positions of cauculation areas in the vertical direction not at equal intervals but at narrower intervals on the upper side and at wider intervals on the lower side. SOLUTION: In image data (monitoring area data) photographed by CCD sensors 10, 12, a coefficient area setting means 15 sets the intervals of calculation areas so that the basic intervals 3 of lines in the photographing direction in an actual space are equal to each other, but the intervals in the vertical direction between the upper end and the lower end are set so that the intervals of the lines become narrower as the distances become far on a monitoring screen 4, in the measurement objective range 1. A calculation area data extraction means 14 extracts image data of a plurality of calculation area parts set by the means 15, a comparison means 16 compares the data at every calculation area, and the distance to an objective obstacle is calculated by a means 18, based on the compared data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an on-vehicle distance measuring device, and more particularly to an on-vehicle distance measuring device for measuring a distance to an obstacle in front of the vehicle using a plurality of calculation areas set in image data. Regarding measuring device.

Vehicle-mounted distance measuring devices are used for vehicle-mounted rear-end collision warning devices and inter-vehicle distance sensors. In addition to automobiles, mobile objects can be used for general transportation equipment such as motorcycles and ships.

[0003]

2. Description of the Related Art Conventionally, various types of rear-end collision warning devices and inter-vehicle distance sensors have been proposed.

For example, there is a method of performing stereo image processing and performing matching with 9 × 9 pixels for 480 × 512 pixels on each of the left and right sides. In addition, the white line detection processing is performed on the image captured by the image capturing means by the dedicated ECU, and the two target lines on the left and right of the lane on which the vehicle is traveling are extracted to determine the target range, and the obstacle is further detected. There is a method in which the detection of is detected by a scanning type laser radar.

In this example, the white line recognition processing recognizes the white line by extracting the contour line after performing spatial differentiation processing on the picked-up image to emphasize the edge of the gradation difference.

Further, as a method of recognizing an image in front of the vehicle by image processing, an edge part having a large gradation difference (luminance difference) in the vertical direction is extracted from the captured image and binarized. There is a method in which a vehicle traveling ahead of the host vehicle is recognized based on the characteristics of the label after the processing such as labeling.

Further, a method has been proposed in which a captured image is divided into a plurality of calculation areas and a vehicle in front of the own vehicle is recognized based on the measurement result of each calculation area.

[0008]

However, in the method of recognizing the front vehicle using the plurality of calculation areas, the far portion in the imaging direction is roughly captured, and therefore the accuracy of the object of distance measurement must be improved. It is necessary to reduce the calculation area. However, if the number of monitoring lines and the number of monitoring windows are increased, extra processing time is required and it becomes difficult to measure the distance in real time. As described above, the method of measuring the distance to the vehicle in front by using the plurality of calculation areas has a disadvantage that there is a certain limit in improving the recognition accuracy.

[0009]

An object of the present invention is to improve the inconvenience of the conventional example, and in particular, in a method of measuring the distance to a target object for each of a plurality of calculation areas in image data, regardless of the distance to the target object. It is an object of the present invention to provide an in-vehicle distance measuring device capable of measuring a distance with a constant accuracy.

[0010]

Therefore, in the present invention, as the first means, two image pickup means for picking up an image of the front of the vehicle and image data (monitor area data) picked up by these image pickup means are used. Calculation area setting means for setting a plurality of calculation areas, a calculation area data extracting means for extracting image data of a plurality of calculation area parts set by the calculation area setting means, and a calculation area data extracting means for extracting image data Comparing means for comparing the calculation area data for each calculation area, and distance calculating means for calculating the distance to the target obstacle for each comparison data based on the comparison data extracted by the comparing means. Moreover, the calculation area setting means sets the vertical distance of the calculation area between the upper end and the lower end in the measurement target range of the image data at equal intervals in the imaging direction in the real space imaged by the imaging means. Vertical calculation area position setting function (first area setting function)
Equipped with.

In the first means, the calculation area setting means sets the vertical position of the calculation area at a narrow interval on the upper side and at a wide interval on the lower side instead of at equal intervals. Therefore,
The location where the calculation area data is extracted is fine for obstacles far away, and coarse for obstacles approaching. Therefore, distance measurement is performed according to the size of the image of the obstacle.

As a second means, in addition to the matters for specifying the first means, the calculation area setting means measures the image data at intervals which are equal to each other in the image pickup direction in the real space imaged by the image pickup means. Horizontal calculation area position setting function (second area setting function) that sets the horizontal interval of the calculation area between the left edge and the right edge for the target range
Equipped with.

As a third means, in addition to the matter for specifying the first means, the calculation area setting means is provided with a setting height (h) of the image pickup means, a viewing angle (θ) of the image pickup means, and the image pickup. It has a function of calculating the position of the calculation area of the image data based on the depression angle (α−θ / 2) of the means.

As a fourth means, in addition to the matters for specifying the third means, the distance calculation means determines the length from the installation position of the image pickup means determined for each calculation area to the position of the road imaged in the calculation area. Based on the information, when the distance measurement result in each calculation area by the distance calculation means is longer than the length information, an error processing unit that makes the distance measurement result in the calculation area an error is additionally provided.

As a fifth means, in addition to the matter for specifying the third means, the distance calculating means calculates the height of the obstacle in the real space based on each distance measurement result determined for each calculation area. Equipped with an obstacle height calculation function.

The present invention aims to achieve the above-mentioned object by each of these means.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a vehicle-mounted distance measuring device according to the present invention. The vehicle-mounted distance measuring device has two imaging means (CC
D sensor) 10, 12 and these CCD sensors 10, 1
Image data captured by 2 (monitoring area data)
Calculation area setting means 15 for setting a plurality of calculation areas, calculation area data extraction means 14 for extracting image data of a plurality of calculation area portions set by the calculation area setting means 15, and the calculation area data A comparison means 16 for comparing the calculation area data extracted by the extraction means 14 for each calculation area, and this comparison means 16
Distance calculating means 18 for calculating the distance to the target obstacle for each comparison data based on the comparison data extracted by
And

CCD cameras 10 and 12 as image pickup means
Is the first CCD camera 10 installed on the left side of the vehicle.
And a second CCD camera 12 installed on the right side of the vehicle. The two CCD cameras 10 and 12 are 70 [m
m] installed at a distance.

As shown in FIG. 2, calculation area setting means 1
Reference numeral 5 is an interval that is equal in the imaging direction in the real space captured by the CCD sensors 10 and 12, and sets a vertical interval of the calculation area between the upper end and the lower end in the measurement target range of the image data. The vertical calculation area position setting function 20 is provided.

Further, the calculation area setting means 15 similarly sets a horizontal interval of the calculation area between the left end and the right end of the measurement target range of the image data at equal intervals in the imaging direction in the real space. The horizontal calculation area position setting function 22 for setting is provided.

This will be described in detail.

The present embodiment measures the distance to an obstacle in front of the host vehicle (such as a vehicle traveling in front) using a multi-stage remote sensor. FIGS. 3 and 4 show the principle of distance measurement by the multi-stage remote sensor. It is an explanatory view for explaining.

FIG. 3 shows the first and second CCD sensors 10,
It is a figure which shows an example of the image data (monitoring area data) from 12. Here, the data captured by each CCD sensor is referred to as image data, and the data corresponding to the measurement target range 1 in this image data is referred to as monitoring area data. The calculation area data extracting means 14 extracts calculation area data from each of these monitoring area data. In the example shown in FIG. 3, for the monitoring area data 10a imaged by the first CCD sensor, the monitoring line 14b is set to 5
Book, monitoring window 14c for each monitoring line 14b
5 are provided at equal intervals on the monitoring area data.

Here, one monitoring window 14c of each monitoring line 14b is used as a calculation area 14a.
In the example shown in FIG. 3, since the setting by the calculation area setting means 15 is not performed, the 25 calculation areas 14a are positioned at equal intervals on the monitoring area data.

The calculation area data extraction means 14 cuts out the calculation area data from the monitoring area data for each calculation area. Here, since the image data is monochrome data having a plurality of gradations (luminances), the calculation area data is as shown in FIG.
As shown in (A) and (B), the luminance data is obtained. Also, the difference in hue of the color data may be compared.

When the edge of the target object is imaged in the calculation area 14a, the calculation area data is different due to the difference in the installation positions of the CCD sensors 10 and 12, as shown in FIG.

As shown in FIG. 4C, the comparison means 16 calculates the calculation area data by the first CCD sensor 10 and the calculation area data by the second CCD sensor 12 for the corresponding calculation area 14a at the same position. Compare with. For example, comparing the positions where the maximum brightness is
Comparison data 1 as shown in FIG. 4C for each calculation area
6a can be obtained.

The distance calculating means 18 calculates the distance to the object on the basis of the triangulation principle based on the comparison data 16 shown in FIG. 4 (C). The number of distance measurement results is the same as the number of calculation areas in which the object is imaged.

With the settings of the monitoring line and the monitoring window shown in FIG. 3, the distance is coarse for a distant object, and the edge is so small that an edge cannot be extracted well for a near object. In order to eliminate this inconvenience, in this embodiment, the calculation area data extracting means 14 is provided with the calculation area setting means 15.

FIG. 5 is a side view showing the positional relationship during measurement. The imaging range 2 for the road 5 is the CCD sensor 1
It is uniquely determined by the depression angle of 0 and 12, the viewing angle, and the installation height. Calculation area 14 defined in monitoring area data
A region between a top end and a bottom end of a is a measurement target range 1 on the road.

When the measurement target range 1 is divided into equal intervals in the image pickup direction, it becomes as shown in FIG. In the example shown in the figure, four lines are divided by five lines arranged at the reference interval 3. The intervals between the lines based on the reference intervals in the measurement target range 1 are not equal on the imaging surfaces of the CCD sensors 10 and 12.

Assuming that the monitor screen 4 parallel to the image pickup planes of the CCD sensors 10 and 12 is as shown in FIG. 5, on the monitor screen 4, the distance between the lines becomes narrower as the measurement distance becomes longer.

Therefore, if the calculation areas defined in the monitoring area data are set at equal intervals on the monitoring area data,
It is coarse for obstacles with a long measurement distance, while too fine for close obstacles with a short measurement distance.

Such a relationship also occurs in the horizontal direction. FIG. 6 is a plan view showing the positional relationship during measurement. Figure 6 is a view from the top of the measurement process (right half).
On the monitor screen 4, the window positions are symmetrical and the window intervals are narrowed toward the center.

The calculation area setting means 15 sets the vertical and horizontal intervals of the calculation area 14a defined in the monitoring area data. That is, the calculation area 14a is set at the interval ratio on the monitor screen 4 shown in FIGS. Hereinafter, an example of a method of calculating the interval ratio on the monitor screen 4 by the calculation area setting means 15 will be described.

7 to 9 show calculation area setting means 15
FIG. 8 is an explanatory diagram for explaining a process of calculating a vertical interval of the calculation area 14a according to FIG.

As shown in FIG. 7, CCD sensors 10, 1
The viewing angle of 2 is θy, and the CCD sensor 1 at the focus position
The height of 0 and 12 is h. The viewing angle θy here corresponds to the measurement target range 1 shown in FIG. 5 instead of the maximum imaging range.

Further, an origin C is defined as an intersection point between the road and a straight line passing through the position closest to the CCD sensors 10 and 12 and the focus position in the measurement target range 1 on the road. The angle formed by the road and the straight line is α. CCD sensor 10,
The depression angle of 12 is α-θy / 2 [degree]. The straight line is
Most CCD sensors 10 and 12 in measurement range 1 on the road
It is a straight line that passes through a position far from and the focus position.

According to the definition shown in FIG. 7, the CCD sensor 1
The coordinates of the focus positions of 0 and 12 are (k, h). Although it is simply shown here for the sake of explanation, an inverted image is actually projected on the imaging surface 11.

In the coordinates shown in FIG. 7, the straight line is expressed by the following equation, and the straight line is expressed by the following equation.

[0041]

[Equation 1]

[0042]

[Equation 2]

In the equation, first, the angle formed by the straight line and the road is α-θy, so the inclination of the straight line is tan (α-θ
y). Therefore, the value a of y when the value of x is k is calculated for the line -1 that passes through the origin C with the same inclination as the straight line. Therefore, the straight line is expressed by the equation.

Then, a straight line passing through the origin C and parallel to the image pickup surface 11 is expressed by the following equation. This straight line is the monitor screen 4 shown in FIG.

[0045]

(Equation 3)

The angle formed by the straight lines is (180-θ
Since y) / 2, the slope of the straight line is as shown in the equation.

Next, as shown in FIG. 8, the measurement object range 1 is divided into n pieces at the reference interval b. Here, a straight line connecting the j-th line counted from the origin and the focus position (k, h) will be described. First, a straight line -1, which is parallel to the straight line and passes through the origin C, is represented by the following expression -1 (4).

[0048]

(Equation 4)

First, the length of the measurement object range 1 is expressed using a formula representing a straight line, and when this is divided into n, the length of the reference interval b is expressed (Formula-1 (1)). Further, the length c from the origin C to the j-th line is defined by the expression -1 (2).

Since the slope of the straight line is represented by h / (c + k), -1 is represented by the expression -1 (3). If this is rearranged, it will become Formula-1 (4).

Since the value d of y when x is k can be expressed by this expression-1 (4), the straight line is expressed by the following expression.

[0052]

(Equation 5)

Next, as shown in FIG. 9, the coordinates of the intersection B between the straight lines are calculated. When the intersection of the straight line and the straight line is A, the ratio of the length AB to the length AC is the ratio of the vertical interval of the calculation area defined in the monitoring area data.

Since the value of y is equal at each intersection, the coordinates of each intersection are defined by simultaneous equations. First, the intersection A is expressed by the equation (5) and the intersection B is expressed by the equation (6). .

[0055]

(Equation 6)

Further, the length AB is expressed by the equation (7) and the length AC
Is expressed by equation (8).

[0057]

(Equation 7)

The calculation area setting means 15 (vertical calculation area position setting function 20) obtains the position of the calculation area 14a in the vertical direction by the above-mentioned equations. In practice, the reference interval b is determined according to the number of monitoring lines 14b, and the formula is defined for each monitoring line 14b. Next, the ratio of AB and AC is calculated for each line, and the position of the monitoring line 14b is calculated by this ratio.

Here, since the positions of other monitoring lines are determined by the number of pixels from the position (origin) of the uppermost monitoring line defined in the monitoring area data, the number of pixels in the vertical direction of the monitoring area data is 256 [dots. ], The calculation area setting means 15 obtains the number of pixels from the origin by the equation (9).

[0060]

(Equation 8)

In this way, the calculation area setting means 15
The installation height (h) of the CCD sensors 10 and 12 and the CC
The positions of the plurality of calculation areas 14a set in the monitoring area data are calculated based on the viewing angles (θy) of the D sensors 10 and 12 and the depression angle (α-θy / 2) of the imaging unit. In the present embodiment, the calculation is performed by defining each straight line with the coordinates having the intersection of the straight line and the road as the origin, but a different method may be used.

For example, the length from the focal point of the straight line to the road may be obtained and the length ratio of each straight line may be obtained.

Next, an example of setting a monitoring window by the calculation area setting means 15 will be described with reference to FIG. Here, the width of the measurement target range in the left-right direction with respect to the traveling direction of the host vehicle is determined according to the purpose of distance measurement. Hereinafter, half of this width is W. The range to be measured in the left-right direction is the width of one lane of a general road because only the traveling lane of the host vehicle is a problem when measuring the inter-vehicle distance (degree of danger). Further, the width in the traveling direction of the road on which the vehicle is traveling may be set as the measurement target range in accordance with the overall processing capacity of the CCD sensors 10 and 12. In this case, the width of the road on which the vehicle is traveling is acquired from a navigation system or a traffic information system such as an optical beacon. Further, the maximum size of the obstacle to be measured may be set in advance, and the measurement target range may be set based on the maximum size obstacle to be recognized.

In the example shown in FIG. 10, the CCD sensor 10,
The horizontal viewing angle of 12 is θx. Further, a plurality of straight lines from the centers of the CCD sensors 10 and 12 to the imaging target range 2W are set as straight lines corresponding to the respective monitoring windows 14c. x
The coordinates indicate the position of the CCD sensors 10 and 12 in the image pickup direction, and the y coordinate indicates the position in the left-right direction when the image pickup direction is the front. A straight line (1) corresponding to the end of the monitoring line 14b determined according to the viewing angle θx of the CCD sensors 10 and 12 is
0). This is the first straight line, and the next straight line with a reference interval b in the traveling direction of the vehicle on the road is
1). In this way, similar to the case shown in FIG. 8, consider n straight lines corresponding to the number of monitoring windows 14c.
If the straight line (10) is the i-th straight line, the straight line (11) becomes i
It becomes the + 1st. First, to define line (11),
Considering an intersection between (10) and the outside of the measurement target range 2W, a straight line orthogonal to the x-axis and including the intersection is assumed to be the y-axis here. The intersection of this y-axis and x-axis is point E.

The straight line (11) is a straight line that connects the intersection of the i-th line and the outside of the measurement target range with the focal position. First, the straight line (11) will be described as the second straight line.

The straight line (10) is expressed by the following equation (10).

[0067]

[Equation 9]

Therefore, as shown in FIG. 11, the distance from the center of the CCD cameras 10 and 12 to the point E is represented. Further, if the straight line (11) is the second straight line, the distance from the point E to the illustrated point F is represented by the distance b, and the straight line (1
If 1) is i-th, it is indicated by the distance ib. With this definition, as shown in FIG. 11, the slope of the straight line (11) is Wi
, And the i-th straight line (11) is expressed by the following equation (11).

[0069]

(Equation 10)

In the equation (11), y when the value of x is 0
The value (Wi) of is expressed by the following equation (12). When Wi is calculated for each i-th straight line, each monitoring window 14b
Is calculated.

Therefore, if the number of pixels in the horizontal direction of the monitoring area data is 512 [dots], the i-th window position can be obtained by the following equation (13).

[0072]

(Equation 12)

As described above, the calculation area setting means 15 (horizontal calculation area position setting function) sets the horizontal position of the calculation area 14a in accordance with the width in the real space.

When the position of the calculation area is set by the method described with reference to FIGS. 7 to 10, it becomes as shown in FIG. In the example shown in FIG. 12, the intervals of the monitoring lines are narrower in the upper part of the monitoring area data, while the intervals become wider toward the lower end. As a result, distances can be measured with great accuracy for distant obstacles, and distances for approaching obstacles are measured in a large calculation area. Can be obtained.
This calculation area is set by the left and right CCD sensors 1.
The same position is set for the monitoring area data output from 0 and 12.

Next, a method of checking the distance measurement result will be described. In the method of setting the calculation area 14a shown in FIG. 12, the distance to the road in the real space imaged for each monitoring line 14b is known. That is, the intersection of the i-th line and the road shown in FIG. 8 is the CCD sensor 10, 1 in the real space.
What [m] is from 2 is calculated from the value of the height h and the like. Obstacles always have height, so the actual distance measurement result is
It should be shorter than the distance on the road defined by this surveillance line.

Therefore, the distance calculating means 18 uses the distance calculating means 18 based on the length information from the installation position of the CCD sensor determined for each calculation area 14a to the position of the road imaged in the calculation area. Each calculation area 14
When the distance measurement result in a is longer than the length according to the length information, an error processing unit 19 that makes the distance measurement result in the calculation area an error is additionally provided.

The error processing section 19 effectively captures a case where distance measurement is not accurately performed due to noise or the like, and further,
It is possible to find out when the depression angle of the camera is deviated from side to side.

Next, a method of calculating the height of the obstacle whose distance has been measured in the real space will be described. Here, the distance calculation means 18 has an obstacle height calculation function for calculating the height of the obstacle in the real space based on each distance measurement result determined for each calculation area. The obstacle height calculation function calculates the height of the obstacle for each calculation area based on the above formula and the distance measurement result.

FIG. 13 is an explanatory diagram showing coordinates when the height of the obstacle is calculated. In FIG. 3, the height is the z coordinate,
The image pickup direction of the CCD sensor shown in FIGS. 7 and 10 is defined as an x coordinate, and the direction orthogonal to the image pickup direction shown in FIG. 10 is defined as ay coordinate. Here, in the i-th monitoring window shown in FIG. 12, the obstacle is caught at the j-th line, and the measured value is X.
The case will be described as an example. At this time, the CCD sensor 1
If 0 and 12 are oriented in the negative direction of the measured value X from the position (k, 0, h), the x coordinate of the obstacle is −X. Of course, the x coordinate may be accurately calculated from the formula. Furthermore, the value of y when this X is substituted into the formula is z
Coordinates. As a result, the position of the obstacle in the real space is known.

Further, the value of y when the measured value X is substituted into the equation (11) becomes the y coordinate shown in FIG. Therefore, i
The actual coordinates of the obstacle whose distance has been measured in the j-th line in the th monitoring window are given by the following equation (14). Thus, when the height of the obstacle is known for each calculation area, the approximate shape of the obstacle can be obtained as coordinates in the real space. Therefore, this outline shape information can be used as a material for determining what the obstacle is.

[0081]

(Equation 13)

Next, an inter-vehicle distance warning device using the on-vehicle distance measuring device according to this embodiment will be described. The inter-vehicle distance warning device recognizes the vehicle ahead, then calculates the distance from the vehicle position to the recognized vehicle, and further, based on the running state of the vehicle and the distance to the vehicle ahead, the vehicle progresses. The degree of danger in the direction is judged and an external display such as an alarm is given.

FIG. 14 is a block diagram showing the structure of an inter-vehicle distance warning device. The inter-vehicle distance warning device includes two CCD sensors 10 and 12, and a control unit 30 (signal processing box) that performs obstacle recognition processing using the above-described calculation area.

Further, the control means 30 captures the steering angle of the steering wheel of the own vehicle and outputs it to the control means 30, and the braking state of the own vehicle and outputs it to the control means 30. And a brake sensor 40.
Further, a vehicle speed sensor, a sensor for capturing a turn signal, or the like may be provided together.

The control means 30 issues a warning regarding the inter-vehicle distance to the obstacle based on the distance measurement result of the obstacle and the traveling state of the host vehicle. The control unit 30 determines, for example, that a warning is given if braking is not performed within a certain distance.

Further, the control means 30 is provided with a speaker 32 for outputting an alarm, a display section 34 for outputting an alarm message and the like, and an input section 36 for inputting various settings.

In the inter-vehicle distance warning device, first, the distance is measured for each calculation area based on the monitoring area data from the CCD sensors 10 and 12. When an obstacle is found by this distance measurement, it is determined whether or not to warn the inter-vehicle distance based on the outputs from the steering wheel steering angle sensor 38 and the brake sensor 40.

[0088]

Since the present invention is constructed and functions as described above, according to this, the calculation area setting means sets the vertical positions of the calculation area at a narrow interval on the upper side and at a lower interval on the lower side. Since the calculation area data extraction means extracts the calculation area data at a fine interval for distant obstacles and at a rough interval for approaching obstacles, the calculation area data extraction means sets the distance to the target object. Despite the fact that the edge portion of the obstacle of a certain size is imaged, the distance calculation means can evenly measure the obstacle within the measurement target range, thus improving the accuracy of image processing. The distance can be measured in detail without the need. As described above, it is possible to provide an excellent vehicle-mounted distance measuring device that has not been available in the related art and can measure the distance with a constant accuracy regardless of the distance to the object.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of calculation area setting means shown in FIG.

FIG. 3 is an explanatory diagram showing an example of a calculation area defined by image data (monitoring area data) imaged by the CCD sensor shown in FIG. 1, and FIG. 3A is a monitoring area by the first CCD sensor. FIG. 3B is a diagram showing data, and is an example of monitoring area data by the second CCD sensor.

4A and 4B are explanatory diagrams for explaining a processing example of the comparison unit shown in FIG. 1, FIG. 4A is a diagram showing an example of calculation area data by the first CCD sensor, and FIG. Is a diagram showing an example of calculation area data by the second CCD sensor, and FIG. 4C is a diagram showing an example of comparison data.

FIG. 5 is an explanatory diagram showing a relationship when the measurement target range and the position of the calculation area are viewed from the side surface.

FIG. 6 is an explanatory diagram showing the relationship when the measurement target range and the position of the calculation area are viewed from above.

FIG. 7 is a first explanatory diagram illustrating a process of calculating a vertical position of a calculation area.

FIG. 8 is a second explanatory diagram for explaining a process of calculating the vertical position of the monitoring Eliu.

FIG. 9 is a third explanatory diagram for explaining the process of calculating the vertical position of the calculation area.

FIG. 10 is a first explanatory diagram for explaining a process of calculating a horizontal position of a calculation area.

FIG. 11 is a second explanatory diagram for explaining the process of calculating the horizontal position of the calculation area.

12 is an explanatory diagram showing an example of monitoring area data in which a calculation area is set by the calculation area setting means shown in FIG.

FIG. 13 is an explanatory diagram showing coordinates when the height of an obstacle is calculated by the distance calculating means shown in FIG.

14 is a block diagram showing a configuration of an inter-vehicle distance warning device using the vehicle-mounted distance measuring device shown in FIG.

[Explanation of symbols]

 10 First CCD Sensor (Imaging Means) 12 Second CCD Sensor (Imaging Means) 14 Calculation Area Data Extracting Means 15 Calculation Area Setting Means 16 Comparing Means 18 Distance Calculating Means 20 Vertical Calculating Area Position Setting Functions 22 Horizontal Calculating Area position setting function

[Equation 11]

Claims (5)

[Claims] 1. A pair of image pickup means for picking up an image of the front of the vehicle, a calculation area setting means for setting a plurality of calculation areas for image data picked up by these image pickup means, and a setting by the calculation area setting means. Calculation area data extracting means for extracting image data of a plurality of calculated calculation area portions, comparison means for comparing the calculation area data extracted by the calculation area data extracting means for each calculation area, and extraction by the comparison means Distance calculation means for calculating the distance to the target obstacle for each of the comparison data based on the compared data, and the calculation area setting means are equal in the imaging direction in the real space imaged by the imaging means. The interval in the vertical direction of the calculation area between the upper end and the lower end in the measurement target range of the image data. Vehicle distance measuring apparatus characterized by having a vertical calculation area position setting function for setting. 2. A calculation area between the left end and the right end of the measurement target range of the image data, wherein the calculation area setting means has equal intervals in the imaging direction in the real space imaged by the imaging means. The vehicle-mounted distance measuring device according to claim 1, further comprising a horizontal calculation area position setting function for setting a horizontal interval of the. 3. The calculation area setting means sets an installation height (h) of the image pickup means and a viewing angle (θ) of the image pickup means.
And the function of calculating the position of the calculation area of the image data based on the depression angle of the image pickup means. 4. The distance calculation means calculates each distance based on length information from the installation position of the image pickup means determined for each calculation area to the position of the road imaged in the calculation area. 4. The vehicle-mounted device according to claim 3, further comprising an error processing unit for making the distance measurement result in the calculation area an error when the distance measurement result in the area is longer than the length according to the length information. Distance measuring device. 5. The distance calculation means has an obstacle height calculation function for calculating the height of the obstacle in real space based on the distance measurement results determined for each calculation area. The vehicle-mounted distance measuring device according to claim 3.