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Description  |
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a driving environment surveillance apparatus for detecting obstacle in front of a running vehicle to inform a driver for easily recognizing the presence of the obstacles.
2. Description of the Prior Art
Conventionally, as the technologies of this kind, there are known an active type one (disclosed in Japanese Patent Publication (Kokoku) No. 60-4011 and so forth) in which a microwave or infrared laser light is transmitted and the reflected signal
from obstacles and so forth is received to detect the distance between vehicles, the presence of the obstacles, the relative distance, the relative speed, and so forth, and a passive type one (disclosed in Japanese Patent Publication (Kokoku) No.
63-38085, Japanese Patent Publication (Kokoku) No. 63-46363, Japanese Patent Publication (Kokai) No. 63-52300, and so forth) in which an image sensor is used to catch an object in front of the vehicle as an image data and so as to detect an obstacle
(including another vehicle) by means of image processing, whereby the distance to the obstacle is detected based on the principle of the triangulation by two sets of optical system. Both of these conventional technologies, although the systems are
different to each other, detect the presence or absence of an obstacle on the front periphery of the running own vehicle, the relative distance to the obstacle, and the relative speed, to output the distance data or the speed data to the driver of the
own vehicle.
FIG. 1 is a plan view showing a conventional driving environment surveillance apparatus disclosed in, for example, the Japanese Patent Publication (Kokoku) No. 61-6349. In the drawing, reference numeral 1 is a vehicle equipped with a laser radar
4, 2 is an obstacle (for example, a vehicle stopping on a side of a road) which is present on the left side in a travelling direction of the vehicle 1, and 3 is another obstacle (for example, a post box) which is present on the right side in the
travelling direction of the vehicle 1.
Also, reference numeral 4 means the laser radar which is provided in the most-front of the vehicle 1 to emit a light beam 6 so as to scan in the range of -10.degree.<.theta.<+10.degree. with respect to a center point of the front-end of
the vehicle. In the laser radar 4, a scanning interval .DELTA..theta. (i.e., an interval between adjacent light beams 6) is set at 0.1.degree..
A description will now be given of the operation.
When the laser radar 4 emits the light beam 6 sequentially starting from the most left end (N=0) toward the right side, the light beams 6 from N=g to N=i return to the vehicle 1 as reflected lights due to the presence of the obstacle 2, and the
laser radar 4 receives the reflected lights. In this connection, the laser radar 4 can not receive the light beam 6 for N=i+1 because of reflection by a side surface of the obstacle 2.
Here, it is assumed that P.sub.1 means a reflection point of the light beam 6 at the most right end (N=i) whose reflected light from the obstacle 2 can be received by the laser radar 4. Accordingly, a distance QP.sub.1 can be detected as
QP.sub.1 =R.sub.1 based upon a reflection time, and a distance P.sub.1 P.sub.3 (=y.sub.1) from P.sub.1 to the center line (the z-axis) of the vehicle can be expressed as follows:
where .theta..sub.i means a deflection angle of the light beam 6 for N=i (the deflection angle 8.sub.i being a known number for the laser radar 4). Further, it is assumed that P.sub.2 means a reflection point of the light beam 6 at the most left
end (N=g) whose reflected light from the obstacle 2 can be received by the laser radar 4. Thereby, it is similarly possible to detect a distance QP.sub.2 as QP.sub.2 =R.sub.2 based upon the reflection time. A distance P.sub.2 P.sub.4 (=y.sub.2) from
the point P.sub.2 to the center line (the z-axis) of the vehicle can be expressed as follows:
where .theta..sub.g means a deflection angle of the light beam 6 for N=g (the deflection angle .theta..sub.g being a known number for the laser radar 4). Accordingly, the recognition of the positions P.sub.1 and P.sub.2 enables recognition of
the relative distance or the azimuth from the vehicle 1 to the obstacle 2.
Detection of the obstacle 3 is identical with that of the obstacle 2, and a description thereof is omitted.
Since a detecting method in a height direction of the obstacles 2 and 3 is identical with that in the horizontal direction in principle, a description thereof is also omitted. In this connection, FIG. 2 shows the light beam 6 emitted from the
laser radar 4 to extend in the height direction.
The conventional driving environment surveillance apparatus is constructed as set forth above. Therefore, it is necessary to provide a fine interval .DELTA..theta. between the light beams 6 emitted from the laser radar 4 in order to detect the
relative distance or the azimuth from the vehicle 1 to the obstacles 2 and 3 with high accuracy. However, as the interval .DELTA..theta. between the light beams 6 becomes more fine, a longer time is required for detecting the obstacles 2 and 3. As a
result, there are problems in that, for example, real-time detected data of the obstacles 2 and 3 can not be provided, and the conventional apparatus is not practical for the vehicle in a running condition.
SUMMARY OF THE INVENTION
In view of the foregoing, it is an object of the present invention to provide a driving environment surveillance apparatus which enables high speed detection even in case of accurate detection of a relative distance and an azimuth to an obstacle
from a vehicle.
It is another object of the present invention to provide a driving environment surveillance apparatus which predicts and indicates an amount of movement of an obstacle so as to enable a driver to more accurately decide potential of collision.
It is still another object of the present invention to provide a driving environment surveillance apparatus in which a driver can easily and intuitively recognize a size and so forth of the obstacle.
It is a further object of the present invention to provide to a driving environment surveillance apparatus which can clearly display an obstacle which is small but may be seriously dangerous.
It is a further object of the present invention to provide to a driving environment surveillance apparatus which can inform a driver of presence of an obstacle even if a temporary error should occur in image processing.
According to the first aspect of the present invention, for achieving the above-mentioned objects, there is provided a driving environment surveillance apparatus which specifies a region where an obstacle is present depending upon an azimuth
detected by an obstacle detecting unit so as to derive a two-dimensional image corresponding to the specified region from an image detecting unit, and extracts the obstacle from the two-dimensional image to calculate a size index of the obstacle.
As stated above, in the driving environment surveillance apparatus according to the first aspect of the present invention, an image processing region limiting unit is provided to specify the region where an obstacle is present depending upon the
azimuth detected by the obstacle detecting unit so as to derive a two-dimensional image corresponding to the specified region from the image detecting unit. Thereby, an obstacle extracting unit on a subsequent stage only has to extract the obstacle from
only the two-dimensional image corresponding to the specified region, resulting in a reduced processing time. Further, the obstacle extracting unit is provided to extract the obstacle from the two-dimensional image so as to calculate the size index of
the obstacle. Therefore, the obstacle detecting unit may have detection accuracy to such a degree that presence of the obstacle can be detected (i.e., accuracy to such a degree that a position of the obstacle can accurately be recognized being
unnecessary), thereby considerably reducing a detection time as compared with a conventional apparatus.
According to the second aspect of the present invention, there is provided a driving environment surveillance apparatus which limits a region specified by an image processing region limiting unit according to a distance detected by an obstacle
detecting unit, and derives a two-dimensional image corresponding to the limited region from the image processing region limiting unit.
As stated above, in the driving environment surveillance apparatus according to the second aspect of the present invention, a correcting unit is provided to limit the region specified by the image processing region limiting unit according to the
distance detected by the obstacle detecting unit, and derive a two-dimensional image corresponding to the limited region from the image processing region limiting unit, thereby more reducing a processing time in an obstacle extracting unit on a
subsequent stage than would be in the first aspect of the present invention.
According to the third aspect of the present invention, there is provided a driving environment surveillance apparatus which predicts an amount of movement of an obstacle depending upon a distance and an azimuth currently detected by a first
driving environment output unit and previously detected distance and azimuth, and specifies a position where the obstacle is present in a real spacial coordinate with respect to a driving road of a vehicle depending upon the distance and the azimuth
currently detected by the first driving environment output unit so as to display a figure indicating a size index and the amount of movement of the obstacle at the specified positions.
As stated above, in the driving environment surveillance apparatus according to the third aspect of the present invention, a predicting unit is provided to predict the amount of movement of the obstacle depending upon the distance and the azimuth
currently detected by the first driving environment output unit and the previously detected distance and azimuth, and a second driving environment output unit is provided to specify the position where the obstacle is present in the real spacial
coordinate with respect to the driving road of the vehicle depending upon the distance and the azimuth currently detected by the first driving environment output unit so as to display the figure indicating the size index and the amount of movement of the
obstacle at the specified position. It is thereby possible to enable a driver to recognize to what extent the obstacle will move.
According to the fourth aspect of the present invention, there is provided a driving environment surveillance apparatus which indicates a size index and an amount of movement of an obstacle by sizes of circles, respectively, and indicates one of
the circles representing the amount of movement by a concentric circle positioned on an outer periphery of the other one of the circles representing the size index of the obstacle.
As stated above, in the driving environment surveillance apparatus according to the fourth aspect of the present invention, a driving environment output unit is provided to indicate the size index and the amount of movement of the obstacle by the
size of the circle, and indicate the circle representing the amount of movement by the concentric circle positioned on the outer periphery of the circle representing the size index of the obstacle. As a result, it is possible to enable a driver to
easily and intuitively recognize the size and so forth of the obstacle.
According to the fifth aspect of the present invention, there is provided a driving environment surveillance apparatus which predicts an amount of movement and a movement direction of an obstacle depending upon a distance and an azimuth currently
detected by a first driving environment output unit and previously detected distance and azimuth, and specifies one position where the obstacle is present depending upon the distance and the azimuth currently detected by the first driving environment
output unit and the other position where the obstacle will be present after the movement depending upon the amount of movement and the movement direction in a real spacial coordinate with respect to a driving road of a vehicle so as to display a figure
indicating a size index of the obstacle at the one position where the obstacle is present and another figure indicating the amount of movement at the other position where the obstacle will be present after the movement.
As stated above, in the driving environment surveillance apparatus according to the fifth aspect of the present invention, a predicting unit is provided to predict the amount of movement and the movement direction of the obstacle depending upon
the distance and the azimuth currently detected by the first driving environment output unit and the previously detected distance and azimuth, and a second driving environment output unit is provided to specify the one position where the obstacle is
present depending upon the distance and the azimuth currently detected by the first driving environment output unit and the other position where the obstacle will be present after the movement depending upon the amount of movement and the movement
direction in a real spacial coordinate with respect to the driving road of the vehicle so as to display the figure indicating the size index of the obstacle at the one position where the obstacle is present and another figure indicating the amount of
movement at the other position where the obstacle will be present after the movement. It is thereby possible to enable a driver to recognize to which direction and to what extent the obstacle will move.
According to the sixth aspect of the present invention, there is provided a driving environment surveillance apparatus which indicates a size index and an amount of movement of an obstacle by sizes of circles, respectively, and indicates a line
which could be a common tangent line for each circle.
As stated above, in the driving environment surveillance apparatus according to the sixth aspect of the present invention, a driving environment output unit is provided to indicate the size index and the amount of movement of the obstacle by the
sizes of the circles, respectively, and indicate the line which could be the common tangent line for each circle. As a result, it is possible to enable a driver to easily and intuitively recognize the size, the movement direction and so forth of the
obstacle.
According to the seventh aspect of the present invention, there is provided a driving environment surveillance apparatus which indicates a size index of an obstacle by a three-dimensional figure having a size according to the index.
As stated above, in the driving environment surveillance apparatus according to the seventh aspect of the present invention, a driving environment output unit is provided to indicate the size index of the obstacle by the three-dimensional figure
having the size according to the index. As a result, it is possible to enable a driver to easily and intuitively recognize the size of the obstacle.
According to the eighth aspect of the present invention, there is provided a driving environment surveillance apparatus which indicates a size index and an amount of movement of an obstacle by a three-dimensional figure having a size according to
the index and the amount of movement.
As stated above, in the driving environment surveillance apparatus according to the eighth aspect of the present invention, a driving environment output unit is provided to indicate the size index and the amount of movement of the obstacle by the
three-dimensional figure having the size according to the index and the amount of movement. As a result, it is possible to enable a driver to easily and intuitively recognize the size and so forth of the obstacle.
According to the ninth aspect of the present invention, there is provided a driving environment surveillance apparatus which extends a size index of an obstacle determined according to calculation in case the obstacle has a height greater than a
width thereof.
As stated above, in the driving environment surveillance apparatus according to the ninth aspect of the present invention, an obstacle extracting unit is provided to extend the size index of the obstacle determined according to the calculation in
case the obstacle has the height greater than the width thereof. As a result, it is possible to indicate an obstacle which is small but may be seriously dangerous in a large size.
According to the tenth aspect of the present invention, there is provided a driving environment surveillance apparatus which refers to a size index of an obstacle preset according to a distance to the obstacle in case the distance and an azimuth
to the obstacle are detected by an obstacle detecting unit, and an obstacle extracting unit outputs no size index of the obstacle, and outputs the size index of the obstacle corresponding to the distance detected by the obstacle detecting unit to a
driving environment output unit.
As stated above, in the driving environment surveillance apparatus according to the tenth aspect of the present invention, an obstacle extracting auxiliary unit is provided to refer to the size index of the obstacle preset according to the
distance to the obstacle in case the distance and the azimuth to the obstacle are detected by the obstacle detecting unit, and the obstacle extracting unit outputs no size index of the obstacle, and outputs the size index of the obstacle corresponding to
the distance detected by the obstacle detecting unit to the driving environment output unit. As a result, it is possible to inform a driver of presence of the obstacle even if a temporary error should occur in image processing.
According to the eleventh aspect of the present invention, there is provided a driving environment surveillance apparatus which outputs, instead of a size index of an obstacle outputted from an obstacle extracting auxiliary unit, a substitution
index having a greater value than that of the size index to a driving environment output unit in case an obstacle detecting unit detects a distance and an azimuth to the obstacle, and an obstacle extracting unit outputs no size index of the obstacle even
after the elapse of a predetermined time or more from the detection of the distance and the azimuth.
As stated above, in the driving environment surveillance apparatus according to the eleventh aspect of the present invention, a data substituting unit is provided to output, instead of the size index of the obstacle outputted from the obstacle
extracting auxiliary unit, the substitution index having a greater value than that of the size index to the driving environment output unit in case the obstacle detecting unit detects the distance and the azimuth to the obstacle, and the obstacle
extracting unit outputs no size index of the obstacle even after the elapse of the predetermined time or more from the detection of the distance and the azimuth. As a result, it is possible to inform a driver of presence of the obstacle even if a
temporary error should occur in image processing, and of potential of serious danger.
According to the twelfth aspect of the present invention, there is provided a driving environment surveillance apparatus in which, in case an obstacle detecting unit detects a distance and an azimuth to the obstacle, and an obstacle extracting
unit does not output a size index of an obstacle even after the elapse of a predetermined time period or more from the detection of the distance and the azimuth, it is decided that any malfunction occurs to indicate the occurrence of the malfunction.
As stated above, in the driving environment surveillance apparatus according to the twelfth aspect of the present invention, a malfunction indicating unit is provided to decide that any malfunction occurs so as to indicate the occurrence of the
malfunction in case the obstacle detecting unit detects the distance and the azimuth to the obstacle, and the obstacle extracting unit does not output the size index of the obstacle even after the elapse of the predetermined time period or more from the
detection of the distance and the azimuth. It is thereby possible to inform a driver of occurrence of error in image processing.
The above and further objects and novel features of the invention will more fully appear from the following detailed description when the same is read in connection with the accompanying drawing. It is to be expressly understood, however, that
the drawings are for purpose of illustration only and are not intended as a definition of the limits of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view showing a conventional driving environment surveillance apparatus;
FIG. 2 is a sectional view showing the conventional driving environment surveillance apparatus;
FIG. 3 is a block diagram showing a driving environment surveillance apparatus according to the embodiment 1 of the present invention;
FIG. 4 is a plan view showing the driving environment surveillance apparatus according to the embodiment 1 of the present invention;
FIG. 5 is an explanatory view illustrating presence of obstacles;
FIG. 6 is an explanatory view illustrating the presence of the obstacles;
FIG. 7 is an outline diagram showing outlines of the obstacles;
FIG. 8 is a display view showing the presence of the obstacles;
FIG. 9 is a block diagram showing a driving environment surveillance apparatus according to the embodiment 3 of the present invention;
FIG. 10 is a plan view illustrating positions where obstacles are present;
FIG. 11 is an explanatory view showing regions to derive two-dimensional images;
FIG. 12 is an explanatory view showing the regions to derive the two-dimensional images;
FIG. 13 is a block diagram showing a driving environment surveillance apparatus according to the embodiment 4 of the present invention;
FIG. 14A is a display view showing the presence of the obstacle;
FIG. 14B is a display view showing the presence of the obstacle;
FIG. 15 is a flowchart diagram showing the operation of the driving environment surveillance apparatus according to the embodiment 4 of the present invention;
FIG. 16 is a display view showing the presence of the obstacle;
FIG. 17 is a display view showing the presence of the obstacle;
FIG. 18 is a display view showing the presence of the obstacle;
FIG. 19 is a display view showing the presence of the obstacle;
FIG. 20 is a display view showing the presence of the obstacle;
FIG. 21 is a display view showing the presence of the obstacle;
FIG. 22 is a display view showing the presence of the obstacle;
FIG. 23 is a display view showing the presence of the obstacle;
FIG. 24 is a display view showing the presence of the obstacle;
FIG. 25 is a block diagram showing a driving environment surveillance apparatus according to the embodiment 9 of the present invention;
FIG. 26 is an outline diagram showing outlines of the obstacles;
FIG. 27 is a block diagram showing a driving environment surveillance apparatus according to the embodiment 10 of the present invention;
FIG. 28 is a graph diagram showing a relation between an index and a distance;
FIG. 29 is a display view showing the presence of the obstacle;
FIG. 30 is a block diagram showing a driving environment surveillance apparatus according to the embodiment 11 of the present invention;
FIG. 31 is a time chart diagram showing the movement of the obstacle;
FIG. 32 is a block diagram showing a driving environment surveillance apparatus according to the embodiment 12 of the present invention; and
FIG. 33 is a time chart diagram showing the movement of the obstacle.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of the invention will now be described in detail referring to the accompanying drawings.
Embodiment 1
A description will now be given of one embodiment of the present invention with reference to the drawings.
FIG. 3 is a block diagram showing a driving environment surveillance apparatus according to the embodiment 1 of the present invention, and FIG. 4 is a plan view showing the driving environment surveillance apparatus according to the embodiment 1
of the present invention. In the drawings, the same reference numerals are used for component parts identical with or equivalent to those in a conventional apparatus, and descriptions thereof are omitted.
Reference numerals 11 to 14 mean laser radars to scan any one of four divided peripheral regions I to IV in a travelling direction of a vehicle 1 so as to detect, if there are obstacles 2 and 20 in the scanning region, a relative distance and an
azimuth from the vehicle 1 to the obstacles 2 and 20. The laser radars 11 to 14 are mounted on front portions P.sub.1 to P.sub.4 of the vehicle 1, and respectively correspond to the regions I, II, III, and IV. An obstacle detecting unit 15 includes the
laser radars 11 to 14.
Reference numeral 16 means an image sensor (an image detecting unit) such as a CCD camera mounted on a position P.sub.5 immediately before a driver seat of the vehicle 1, for detecting two-dimensional images of the peripheral regions I to IV, 17
is an image processing region limiting unit for specifying a region where the obstacles 2 and 20 are present depending upon azimuths .theta..sub.1 to .theta..sub.4 detected by the laser radars 11 to 14 so as to derive the two-dimensional image
corresponding to the specified region from the image sensor 16, 18 is an obstacle extracting unit for extracting the obstacles 2 and 20 from the two-dimensional image provided by the image processing region limiting unit 17, and for calculating size
indexes S of the obstacles 2 and 20, and 19 is a driving environment output unit for specifying positions where the obstacles 2 and 20 are present in a real spacial coordinate with respect to a driving road of the vehicle 1 based upon the distances and
the azimuths detected by the laser radars 11 to 14 so as to display figures indicating the size indexes S of the obstacles 2 and 20 at the specified positions.
A description will now be given of the operation.
The laser radars 11 to 14 emit pulse-like laser light forward at a predetermined time interval, and receive the laser light reflected by the obstacles 2 and 20 as reflected light if the obstacles 2 and 20 are present in front of the vehicle to
measure the reflection time so as to detect the distances to the obstacles 2 and 20. Referring to FIG. 4, the obstacle 2 is present in the regions I and II, and the obstacle 20 is present in the region III. Hence, the laser radars 11, 12, and 13 can
receive the reflected light and the laser radar 14 receives no reflected light.
The laser radars 11 to 14 are mounted for each region so that the laser radar 11 outputs the azimuth .theta..sub.1 representative of the region I an azimuth signal when the laser radar 11 detects the obstacle. Accordingly, in case of FIG. 4, the
laser radars 11, 12, and 13 output respective azimuth signals .theta..sub.1, .theta..sub.2, and .theta..sub.3 since the laser radars 11 to 13 detect the obstacles.
For purpose of more specific discussion, a description will now be given of the operation with reference to a condition in front of the vehicle 1 as shown in FIG. 5. In FIG. 5, reference numerals 21 to 23 mean other vehicles corresponding to
obstacles.
Referring to FIG. 5, the obstacles 21 to 23 are present in the regions I and II so that the laser radars 11 and 12 receive the reflected light (the laser radars 13 and 14 receiving no reflected light because the obstacles 21 to 23 are absent in
the regions III and IV).
Therefore, the laser radars 11 and 12 measure the reflection times to determine the distances to the obstacles 21 to 23 so as to output signals indicating distances r.sub.1, r.sub.2, and r.sub.3 and the azimuths .theta..sub.1 and .theta..sub.2.
Further, the image processing region limiting unit 17 receives the signals indicating the azimuths .theta..sub.1 and .theta..sub.2 from the laser radars 11 and 12, thereby recognizing the presence of the obstacle 21 in the region I, and the
presence of the obstacles 22 and 23 in the region II.
Two-dimensional images in the regions I to IV are imaged by the image sensor 16. The image processing region limiting unit 17, however, derives only the two-dimensional images corresponding to the regions I and II from the image sensor 16 (see
FIG. 6) since no obstacle is present in the regions III and IV. Thereafter, the image processing region limiting unit 17 outputs the two-dimensional images corresponding to the regions I and II to the obstacle extracting unit 18 on a subsequent stage.
This is because the obstacle extracting unit 18 is operated to extract obstacles, and obstacle extracting processing becomes unnecessary in the region where any obstacle is not present absolutely.
Subsequently, the obstacle extracting unit 18 extracts the obstacles 21 to 23 from the two-dimensional images corresponding to the regions I and II, and calculates the size indexes S of the obstacles 21 to 23. In this case, the obstacles 21 to
23 are extracted by well-known image processing (i.e., basic image processing such as edge detection, or line connection), and a brief description will be given of the image processing hereinafter while a detailed description thereof is omitted.
In the image processing, the two-dimensional image is differentiated in horizontal and vertical directions for the edge extraction, and thereafter each vicinal point is connected to each other (line connection) in the extracted edge to provide a
visible outline of an object so as to regard the outline as the obstacle.
In order to decide a kind of the obstacle, there is provided an extraction frame corresponding to an outside dimension of, for example, the vehicle at a position where the obstacle such as the vehicle may be present based upon the distance data
provided from the laser radars 11 to 14. If the extraction frame is matched with the outline of the object, the outline of the object can be regarded as the obstacle such as the vehicle. Otherwise, the outline is regarded as a background object or the
other obstacle such as a road object.
On the other hand, the outlines of the obstacles 21 to 23 are provided as shown in FIG. 7 by the image processing, and the size index S of the obstacle can be calculated by each width x and height y of the obstacles 21 to 23. That is, the size
index S.sub.1 of the obstacle 21, the size index S.sub.2 of the obstacle 22, and the size index S.sub.3 of the obstacle 23 can be expressed as follows: ##EQU1##
As described above, the obstacle extracting unit 18 calculates the size indexes S.sub.1, S.sub.2, and S.sub.3 of the obstacles 21 to 23, and outputs them to the driving environment output unit 19. Therefore, the driving environment output unit
19 can specify the position where the obstacles 21 to 23 are present in the zeal spacial coordinate with respect to the driving road of the vehicle 1 depending upon the distances r.sub.1, r.sub.2, and r.sub.3 and the azimuths .theta..sub.1 and
.theta..sub.2 detected by the laser radars 11 and 12 (see FIG. 8).
In this case, since there is only one obstacle in the region I, the position of the obstacle 21 can be specified by the distance r.sub.1 and the azimuth .theta..sub.1. On the other hand, there are two obstacles in the region II so that the
driving environment output unit 19 decides a lateral relation between the positions of the obstacles 22 and 23 depending upon the two-dimensional image outputted from the image sensor 16, and specifies the positions of the obstacles 22 and 23 based upon
the resultant decision and the distances r.sub.2 and r.sub.3 to the obstacles 22 and 23.
Finally, as shown in FIG. 8, the driving environment output unit 19 indicates circles having radii proportional to the size indexes S.sub.1 to S.sub.3 of the obstacles 21 to 23 extracted by the obstacle extracting unit 18 at the specified
positions.
Thereby, a driver can recognize the positions and the sizes of the obstacles 21 to 23.
In the embodiment 1, it is possible to perform the image processing at a high speed, and provide real-time processing since the image processing region is limited. In case | | |
