JPH11326518A - Obstacle detecting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an obstacle detecting apparatus by which an investigation range is expanded up to a traffic lane, to be changed, in addition to a traffic lane being run at present when a traffic laner is changed during a running operation and by which a preceding vehicle in another traffic lane is captured. SOLUTION: A transmitting element 4, a transmitting lens 5 and a lens movement mechanism 6 constitute an investigation-wave transmission part 2. In addition, the lens movement mechanism 6 can be moved in the direction of an arrow (a) and the direction of an arrow (b). When the transmitting lens 5 is moved in the direction of the arrow (a), investigation waves T are scanned in the right and left direction, and their scanning angle is changed by changing their movement width. On the other hand, when the transmitting lens 5 is moved to the direction of the arrow (b), the distance between itself and the transmitting element 4 is changed, and the beam angle of the investigation waves T is changed. Then, when an operation in which a driver changes a traffic lane is sensed by a turn signal indicator 13 or a steering angle sensor 14, an investigation range is expanded by the lens movement mechanism 6. A preceding vehicle which is running on a traffic laner on which the own vehicle is running and a preceding vehicle which is running on a traffic lane to which the own vehicle is going to move are captured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an obstacle detecting device suitable for use in, for example, an automatic speed control and an automatic stop control of a vehicle.

[0002]

2. Description of the Related Art In general, some vehicles have an automatic speed control (ASCD) used when cruising at a substantially constant speed like a highway. In this auto speed control, there is a speed control type auto speed control that cruises at a set predetermined speed, and a cruise at a speed that keeps the inter-vehicle distance with the preceding vehicle constant, and it is set when the preceding vehicle disappears There are two types: an auto speed control of an inter-vehicle distance control system that cruises at a predetermined speed.

[0003] In the automatic speed control of the following distance control system, the accelerator opening is controlled by an actuator so that the vehicle cruises at a speed at which the distance between the host vehicle and the preceding vehicle becomes constant. When the accelerator opening is closed, braking is automatically performed to reduce the speed, and when the inter-vehicle distance is widened, the accelerator is opened to accelerate and the inter-vehicle distance is always kept constant.

[0004] An obstacle detecting device is used as one of the methods for measuring the inter-vehicle distance from a preceding vehicle. The obstacle detecting device transmits a search wave in the traveling direction of the own vehicle. And a receiving means for receiving a reflected wave when the search wave transmitted from the transmitting means is reflected by a preceding vehicle serving as an obstacle, and measures a time from transmission of the search wave to reception of the reflected wave. In this way, the inter-vehicle distance is measured, and the relative speed with respect to the preceding vehicle is measured from the temporal change of the inter-vehicle distance.

[0005]

However, as described above, in the method of measuring the distance between vehicles by using a search wave according to the prior art, the search wave transmitted from the transmitting means is different from the direction of the own vehicle. Because the signal is transmitted in a fixed direction with a certain width, when the road turns into a curve or a slope, the vehicle ahead may be lost. Measure the distance.

For this reason, in the automatic speed control, when the preceding vehicle actually travels on the same lane even though the preceding vehicle is actually traveling on the same lane,
There is a case where the preceding vehicle cannot be detected because it deviates from the search range of the search wave. In this case, the automatic speed control temporarily switches from the following distance control to the speed control,
When a preceding vehicle is detected again after passing through a curve or a slope, the mode is switched to the following distance control. As a result, in a vehicle equipped with an automatic speed control as in the prior art, there is a problem that the control is switched every time the vehicle passes through a curve or a slope, and the speed of the vehicle changes, thereby deteriorating ride comfort.

Further, as described above, since the exploration wave transmitted from the transmitting means has a certain width and captures only the preceding vehicle on the same lane, for example, the preceding wave traveling on another lane I couldn't know the condition of the vehicle.

The present invention has been made in view of the above-mentioned problems of the prior art, and the present invention expands a search range to a lane to be changed in addition to the currently running lane when the lane is ahead during driving. It is an object of the present invention to provide an obstacle detecting device as described above.

[0009]

Means for Solving the Problems To solve the above-mentioned problems, an obstacle detection device adopted by the invention of claim 1 is:
Transmitting means for transmitting a search wave forward in the traveling direction of the vehicle, scanning means for scanning the search wave transmitted from the transmitting means at least in the left-right direction with respect to the traveling direction, and scanning by the scanning means Receiving means for receiving a reflected wave when the exploration wave is reflected by a forward obstacle, and controlling the scanning means when it is determined that an obstacle has been captured from the reflected wave received by the receiving means, from the transmitting means Following means for following the transmitted exploration wave in accordance with the movement of the obstacle, lane change sensing means for sensing an operation when the vehicle changes lanes, and when lane change operation is sensed by the lane change sensing means And a search range expanding means for changing one or both of the scanning angle of the search wave by the scanning means and the beam angle of the search wave by the transmission means to widen the search range. In the door.

With this configuration, when the reflected wave from the preceding vehicle, which is an obstacle, is received by the receiving means, the follow-up means sets the irradiation direction of the search wave so that the reflected wave can always be received by the receiving element. Can be controlled by swinging by the scanning means, so that the vehicle can follow the movement of the preceding vehicle, and can continue to follow the vehicle even when the vehicle passes through a curve or a slope.

When a lane change operation is detected by the lane change detecting means, the search range expanding means changes one or both of the scanning angle of the search wave by the scanning means and the beam angle of the search wave by the transmission means. By doing so, it is possible to widen the search range and catch the preceding vehicle traveling on the destination lane.

According to a second aspect of the present invention, the search range expanding means is configured to widen the angle at which the search wave scanned by the scanning means swings in the left-right direction.

With such a configuration, when the angle at which the scanning wave is swung in the left-right direction by the scanning means is widened, the search range of the search wave irradiated toward the front of the own vehicle can be widened. It is possible to capture the preceding vehicle within the search range.

According to a third aspect of the present invention, the search range enlarging means is configured to widen the angle at which the search wave transmitted by the transmitting means is irradiated forward.

With such a configuration, when the angle at which the search wave is emitted forward by the transmitting means is widened, the search range of the search wave emitted toward the front of the vehicle can be widened, A preceding vehicle within the search range can be captured.

According to a fourth aspect of the present invention, when the vehicle is traveling on the own lane, the following means follows the preceding vehicle traveling on the own lane, and the lane change of the own vehicle is completed by the lane change detecting means. Is detected, the vehicle follows the preceding vehicle traveling on the destination lane.

With such a configuration, when there is a preceding vehicle traveling in front of the own vehicle, the following means controls the scanning means so as to follow the search wave in accordance with the movement of the preceding vehicle. Therefore, even when the vehicle passes through a curve or a slope, the tracking by the exploration wave can be continued.
In addition, even after the lane change, the following operation can be performed on the preceding vehicle traveling on the destination lane.

According to a fifth aspect of the present invention, the lane change detecting means is activated when the vehicle changes lanes.
Alternatively, the steering angle sensor detects the steering angle of the steering wheel when the vehicle changes lanes.

With such a configuration, in order to detect a lane change of the vehicle, an existing direction indicator or a steering angle sensor detects the lane change by the own vehicle without separately providing a sensor or the like for the vehicle. can do.

According to the present invention, when the lane change detecting means detects that the lane change of the own vehicle is completed, the search range expanded by the search range expanding means is returned to the reduction side. Has been established.

With this configuration, when the own vehicle has completed the lane change, the search range expanded by the search range expanding means is returned to the reduction side again, and the preceding vehicle exists on the destination lane. If there is, the following means controls the scanning means to perform the following operation, and if there is no preceding vehicle on the destination lane, the scanning means performs scanning with the search wave.

According to a seventh aspect of the present invention, at least one of a relative position, an inter-vehicle distance, and a relative speed between the own vehicle traveling from the reflected wave received by the receiving means and a preceding vehicle traveling ahead of the own vehicle. Is provided as travel information calculating means.

With this configuration, it is possible to calculate at least one of the relative position, the inter-vehicle distance, and the relative speed between the own vehicle and an obstacle such as a preceding vehicle in the search range. The driver can recognize the information of the preceding vehicle traveling ahead.

According to an eighth aspect of the present invention, there is provided a notifying means for notifying the driving information calculated by the driving information calculating means.

[0025] With this configuration, the driver can obtain not only the preceding vehicle traveling on the same lane but also the traveling information of the relative position, the inter-vehicle distance, and the relative speed of the preceding vehicle traveling on the destination lane. Can be recognized from the notification means.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an obstacle detecting device according to an embodiment of the present invention will be described in detail with reference to FIGS.

Reference numeral 1 denotes a preceding vehicle detecting device as an obstacle detecting device mounted on the front side of the vehicle A. The preceding vehicle detecting device 1 includes a search wave transmitting unit 2, a lens moving mechanism 6, and a reflected wave receiving unit, which will be described later. 7 and a control unit 11. For convenience, a vehicle equipped with the preceding vehicle detection device 1 is referred to as a host vehicle A, a vehicle traveling in the same lane as the host vehicle A is referred to as a preceding vehicle B, and a vehicle traveling in another lane is referred to as a preceding vehicle C. .

Reference numeral 2 denotes a search wave transmitting unit as a transmitting means. The search wave transmitting unit 2 receives a search wave signal (for example, 0.1 to 1.0 M) according to a command from the control unit 11.
Hz) is connected to the output side of the transmitting circuit 3. The search wave transmitting unit 2 receives the search wave signal output from the transmission circuit 3 and transmits a laser diode L that generates a laser beam L and transmits the laser beam L generated from the transmitter element 4. The transmission lens 5 is configured to restrict diffusion by changing the wavelength and to change to the search wave T.

Reference numeral 6 denotes a lens moving mechanism which also serves as a scanning means and a search range enlarging means. The lens moving mechanism 6 is driven by a drive source (not shown) such as an electromagnetic actuator in accordance with a command from the control unit 11. 5 is moved in the vertical direction, the horizontal direction, and the front-back direction.

Here, as shown in FIG. 1, the lens moving mechanism 6 moves the transmitting lens 5 in the direction indicated by the arrow a (left-right direction) while keeping the distance between the transmitting lens 5 and the transmitting element 4 substantially constant.
As shown in FIG. 2, the search wave T is reciprocated in the search range of the scan angle θ1, for example, when the distance is 100 m.
Constitutes a scanning means for scanning at ± 2 m in the left-right direction.

Further, the lens moving mechanism 6 increases the moving width of the transmitting lens 5 moved in the direction of the arrow a in FIG. 1 by the lens moving mechanism 6 so that the probe wave T as shown in FIG. Scan angle when swinging in the horizontal direction
From θ to θ2, and the search wave T is
For example, the distance is increased to ± 20 m in the left-right direction at a distance of 100 m.

Further, as shown in FIG. 1, the lens moving mechanism 6 moves the transmitting lens 5 in the direction of arrow b (front-back direction), and adjusts the distance between the transmitting lens 5 and the transmitting element 4. As shown in FIG. 3, the beam angle when radiating the search wave T forward is changed from a narrow beam angle α to a wide beam angle β.
The irradiation range is expanded to ± 2 m in the left-right direction at a distance of 100 m, for example. Here, the narrow beam angle α is an angle formed by a linear beam that suppresses diffusion of the laser light L generated from the transmitting element 4.

On the other hand, when the beam angle is widened to a wide beam angle β, the search wave T becomes the scanning angle θ by the operation described later.
3, the search range of the search wave T is, as shown in FIG.
As in the case of swinging in step 2, the distance is ± 20 m in the horizontal direction at a distance of 100 m.

The beam angle of the probe wave T is made closer to α by moving the focal length of the transmitting lens 5 closer to the transmitter element 4 by the lens moving mechanism 6, and the beam angle of the probe wave T is moved away from this focal length. Can be β.

Reference numeral 7 denotes a reflected wave receiving section as a receiving means. The reflected wave receiving section 7 receives the reflected wave R when the search wave T transmitted from the search wave transmitting section 2 is reflected by the preceding vehicle B. r, and a plurality of photodiodes that detect the position of the reflected wave R by receiving the received wave r from the receiving lens 8 and output a received signal, specifically, for example, four And a receiving element 9 (see FIG. 4) composed of photodiodes 9A to 9D.

Here, a receiving circuit 10 for correcting the signal from the receiving element 9 and outputting the received signal to the control unit 11 is connected to the output side of the receiving element 9. The focal length of the receiving lens 8 is set such that the received wave r is focused on the surface of the receiving element 9.

As shown in FIGS. 4 and 5, the receiving element 9 is configured by arranging PIN type photodiodes 9A to 9D made of photoelectric conversion elements in a 2 × 2 square shape. Therefore, the photodiodes 9A to 9D
Are four areas where only one photodiode is detected among the photodiodes 9A to 9D and four areas where two photodiodes are detected, depending on the position where the received wave r is irradiated.
The number of detected areas is one. in this case,
Even with the four photodiodes 9A to 9D, the irradiation direction of the search wave T can be detected in nine types of areas (see Table 1).

[0038]

[Table 1]

Here, as shown in FIGS. 4 and 5, for example, when the reception signal is output only from the photodiode 9B, the area irradiated with the reception wave r is "5". In addition, the received signal has two photodiodes 9A and 9A.
When the signal is output from D, the area irradiated with the reception wave r 'is "2". Further, when the reception signal is output from the four photodiodes 9A, 9B, 9C, 9D, the area irradiated with the reception wave r ″ is “1”. Thus, the photodiodes 9A to 9A
Based on the received signals output from D, the range searched by the receiving element 9 through the receiving lens 8 can be divided into nine areas and detected.

Reference numeral 11 denotes a control unit. The control unit 11 is constituted by a microcomputer. On the input side, a lens moving mechanism 6, a receiving circuit 10 of a reflected wave receiving unit 7, a direction indicator 13 described later, a steering angle sensor 14 are provided. Is connected, and an alarm 15 and a monitor 1 are provided on the output side.
6 are connected. Also, the control unit 11
Is provided with a storage device 12, and in the storage device 12,
A preceding vehicle detection program as shown in FIGS. 6 and 7 is stored.

Reference numeral 13 denotes a direction indicator, and reference numeral 14 denotes a steering angle sensor. The direction indicator 13 and the steering angle sensor 14 are configured as lane change detecting means for detecting an operation when the vehicle A changes lanes.

Reference numeral 15 denotes an alarm device constituted by a buzzer, a lamp, and the like. The alarm device 15 warns a danger when, for example, the inter-vehicle distance to a preceding vehicle becomes short.

Reference numeral 16 denotes a monitor device provided in the vicinity of the driver's seat of the vehicle A as a notifying means. The monitor device 16 is composed of a liquid crystal, a HUD (head-up display) or the like, and is shown in FIGS. Thus, the calculation result of the inter-vehicle distance D or the relative speed ΔV between the own vehicle A and the preceding vehicles B and C is displayed.

Further, the control unit 11 includes:
A position detecting function for detecting the positions of the preceding vehicles B and C based on the reception signal output from the receiving element 9 of the reflected wave receiving unit 7, and the distance between the host vehicle A and the preceding vehicles B and C by the position detecting function. An inter-vehicle distance calculation function for calculating a distance, a relative speed calculation function for calculating a relative speed from a change in the inter-vehicle distance calculated by the inter-vehicle distance calculation function, and an alarm 15 when the preceding vehicle is determined to be too close An alarm actuating function for causing the vehicle to follow the preceding vehicle B by adjusting the irradiation direction of the search wave T by the lens moving mechanism 6 after receiving the received wave r by the receiving element 9 of the reflected wave receiving unit 7;
A search range expanding function for expanding the search range of the search wave T when the vehicle A changes lanes is provided.

The preceding vehicle detection device 1 according to the present embodiment
Is configured as described above. Next, FIGS. 8 and 9 show the preceding vehicle detection program shown in FIGS. 6 and 7 and the display of the monitor device 16, and FIG.
The operation will be described with reference to FIG. The arrows at the center of the own vehicle A and the preceding vehicle B indicate the traveling directions of the vehicles.

First, in step 1, the lens moving mechanism 6
The transmission lens 5 is moved in the left-right direction with a small moving width, and the search wave T having the beam angle α is swung at the scanning angle θ1 toward the front from the transmission lens 5 mainly on the lane in which the vehicle A travels. Let it.

In step 2, it is determined whether or not a received signal is output from the reflected wave receiving unit 7. If "YES" is determined, the process proceeds to step 3, and in step 3, scanning of the search wave T is performed. Stop.

Next, at step 4, it is determined whether or not the driver intends to change lanes based on a signal output from the direction indicator 13 or the steering angle sensor 14.

Here, as a specific example of determining the intention to change lanes, the direction indicator 13 is operated to the lane side to which the driver wants to move three seconds before changing lanes. It is determined that there is an intention to change lanes. The driver's intention to change lanes may be determined based on a signal output from the steering angle sensor 14.

If "YES" is determined in the step 4, the processing from the step 11 described later is performed, and the "NO"
When the determination is made, the tracking processing of steps 5 to 8 is performed.

That is, in step 5, the received signal is read again, and in step 6, which of the photodiodes 9 A to 9 D of the receiving element 9 has output the read received signal is output. Is determined, a specific area is calculated from the nine types of areas of the receiving element 9 and stored in the storage device 12.

In step 7, the inter-vehicle distance D and the relative speed ΔV from the vehicle A to the preceding vehicle B are calculated based on the area specified in step 6, and the results are stored in the storage device 12, and the lens moving mechanism 6 is operated. To follow the preceding vehicle B.

In step 8, it is determined whether or not the reflected wave R is received by the receiving element 9 through the receiving lens 8, and a receiving signal is output from the receiving element 9. If "YES", the process proceeds to step 8. 4 and the processing after step 4 is performed.

That is, the specific area of the preceding vehicle B is calculated by determining which of the photodiodes 9A to 9D the received signal is output, and is stored in the storage device 12. I do. Further, in step 7, the lens moving mechanism 6 is controlled based on the specific area to cause the preceding vehicle B to follow.

On the other hand, if “NO” is determined in step 8, it is determined that the preceding vehicle B has deviated from the range of the scanning angle θ 1 of the search wave T, and the process returns to step 1 and the transmission lens is transmitted by the lens moving mechanism 6. The search wave T is scanned by moving 5.

If "NO" is determined in the step 2, the preceding vehicle does not exist on the lane in which the own vehicle A travels. It is determined whether or not there is an intention to change lanes, depending on whether or not the driver has operated 13. Here, "NO"
When the determination is made, the process returns to step 1 to scan the search wave T at the scan angle θ1. On the other hand, “YES” in the step 9
If it is determined, the process proceeds to step 11.

Now, the processing after step 11 is the processing when it is determined that the vehicle A has an intention to change lanes.

First, in step 11, it is determined that the lane change operation has occurred regardless of the operation of scanning the search wave T at the scan angle θ1 and the operation of following the preceding vehicle B with the search wave T. Since this is the case (steps 4 and 9), before performing this processing, it is determined whether or not the preceding vehicle B is on the own lane in order to confirm the operation of the exploration wave T so far.

If "YES" is determined in step 11, it is determined that the exploration wave T is following the preceding vehicle B, and the process proceeds to step 12, where the beam angle is changed as shown in FIG. Is expanded by the lens moving mechanism 6 from α to β, and the scanning angle at which the search wave T swings from θ1 to θ3 to expand the search range.

On the other hand, if "NO" is determined in the step 11, it is determined that the search wave T has been scanned, and the process proceeds to a step 13. In the step 13, as shown in FIG.
With the beam angle set to α, the search range is expanded by expanding the scan angle at which the search wave T swings from θ1 to θ2 by the lens moving mechanism 6, and the process proceeds to step.

As described above, in any of steps 12 and 13
However, the exploration range by the exploration wave T is expanding.

At step 14, the received signal is read. At step 15, it is determined whether or not the received signal is output from the reflected wave receiving unit 7. If “YES” is determined, the process proceeds to step 16. In this step 16, the area where the preceding vehicles B and C are present is specified from the received signal, and the relative position, the inter-vehicle distance D and the relative speed ΔV from the own vehicle A to the preceding vehicles B and C are calculated from this area, This is stored in the storage device 12, and this traveling information is displayed on the monitor device 16 (see FIG. 8). Here, the relative position refers to a relative positional relationship between the lane in which the vehicle A is traveling and the lane in which the preceding vehicle is traveling.

In step 17, it is determined whether or not the lane change has been completed by determining whether or not the direction indicator 13 has been canceled (or whether or not the steering operation of the steering wheel has been returned by a signal from the steering angle sensor 14). This step 17 is performed until the lane change is completed.
Wait at. Then, when the lane change is completed, step 1
Move to 8.

In step 18, since the lane change of the own vehicle A has been completed, the preceding vehicle C traveling on the destination lane is set as the preceding vehicle B followed by the search wave T. In step 19, The beam angle returns from β to α, and returns to step 4 described above. And step 5 mentioned above
8, the operation of following the preceding vehicle B is performed.

On the other hand, if "NO" is determined in the step 15, even if the search range by the search wave T is expanded, no preceding vehicle exists on the road. The beam angle is returned from β to α, and the process returns to step 1. Then, the search wave T is changed to the scanning angle θ1.
Is performed in the range of.

As described above, in the preceding vehicle detecting device 1 according to the present embodiment, as shown in FIG. 10, after the preceding vehicle B is captured, the exploration wave T follows the preceding vehicle B. Then, as shown in FIG. 11, even if the preceding vehicle B is traveling on a curve, the exploration wave T can follow the traveling state of the preceding vehicle B, and the preceding vehicle B always keeps following the traveling state. Can be.

Further, if the lens moving mechanism 6 can adjust the exploration wave T not only in the left-right direction but also in the up-down direction, after the preceding vehicle B is captured, the preceding vehicle B passes on a slope. However, it is also possible to change the irradiation direction of the exploration wave T in the up-down direction and to follow it.

The transmitting lens 5 is held by a lens moving mechanism 6, and the transmitting lens 5 can be moved in the vertical direction, the horizontal direction, and the front and rear direction by the lens moving mechanism 6. Thus, the transmitting wave 5 is reciprocated in the left and right directions by the lens moving mechanism 6 so that the search wave T transmitted from the search wave transmitting unit 2 is scanned in the left and right direction with respect to the traveling direction of the vehicle A. Can be. Further, by adjusting the moving width of the transmitting lens 5 by the lens moving mechanism 6, for example, the search wave T can be scanned in two search ranges of the scan angles θ1 and θ2. Further, by causing the transmitting lens 5 to approach and separate from the transmitting element 4,
The search wave T can switch its beam angle from a narrow beam angle α to a wide beam angle β. As described above, by controlling the lens moving mechanism 6, the search range scanned by the search wave T can be adjusted.

Further, in this embodiment, when the search wave T is in the scanning operation of the preceding vehicle by the operation of the direction indicator 13 or the steering operation of the steering wheel performed by the driver as the intention to change lanes, the search wave T Scan angle T
The exploration range has been expanded. Accordingly, not only the lane in which the vehicle A travels, but also the left and right lanes can be set as the search range, and the preceding vehicle can be monitored by the search wave T including the left and right lanes.

On the other hand, when the search wave T is following the preceding vehicle traveling on the same lane, the search wave T is expanded by increasing the beam angle to β and scanning at the scan angle θ3, thereby causing The preceding vehicle traveling on another lane can be monitored by the search wave T while the preceding vehicle traveling on the vehicle is captured by the search wave T.

Thus, for example, when the vehicle A is going to move to the right lane, the relative position, the inter-vehicle distance D, the relative speed ΔV, etc. of the preceding vehicle C running on this lane can also be calculated. After the change is completed, the search wave T can be made to directly follow the preceding vehicle C, and the time spent for the scanning operation for following the preceding vehicle C by the scanning operation can be omitted.

Further, since the inter-vehicle distance D and the relative speed ΔV are stored in the storage device 12 in advance, it is possible to smoothly control the speed of the own vehicle A with respect to the preceding vehicle C while moving. It is possible to shift to a following operation.

The traveling information ahead of the vehicle A is shown in FIG.
As shown in FIG. 9, the preceding vehicle B,
Relative position of C with respect to own vehicle A, distance D between vehicles, relative speed Δ
V and the like are displayed, and the driver can know the traveling information in front of the vehicle through the monitor device 16, and the safety can be improved as compared with the visual confirmation.

Further, even when the search wave T is made to follow the preceding vehicle B traveling on the same lane, if the direction indicator 13 is operated to change the lane, the beam angle of the search wave T is reduced. The preceding vehicle C that spreads and scans and travels in another lane
, The traveling information of another lane can be obtained in a state where the operation of following the search wave T with respect to the preceding vehicle B is continued.

As shown on the monitor 16 in FIGS. 8 and 9, the preceding vehicle C located in the left lane has a relative speed ΔV of −20 km / h. Since the change is dangerous, the monitoring device 1
The safety of the traveling of the vehicle A can be enhanced by indicating the display of 6 and alerting the driver with an alarm 15 to alert the driver.

Thus, when the preceding vehicle detection device 1 according to the present embodiment is used for automatic speed control, the time between transmission of the search wave T and reception of the reflected wave R determines the connection between the own vehicle A and the preceding vehicle B. The inter-vehicle distance D is measured, and the cruise is controlled by controlling the speed so that the inter-vehicle distance D becomes a predetermined constant inter-vehicle distance.

At this time, once the preceding vehicle B is captured by the preceding vehicle detection device 1, the preceding vehicle B always follows the search wave T unless the preceding vehicle B leaves the traveling lane of the own vehicle A. Therefore, in the present embodiment, unlike the related art, the speed of the vehicle A during the auto speed control is stabilized without frequently switching the auto speed control from the inter-vehicle distance control to the speed control, and the riding comfort is improved. Can be improved.

Further, when the vehicle A attempts to change lanes, the search wave T transmitted from the search wave transmitter 2 can be expanded by increasing the scanning angle or the beam angle at which the search wave T swings. Since the search range is expanded, not only the preceding vehicle B traveling on the same lane but also the preceding vehicle C traveling on another lane can be captured, and the preceding vehicle C traveling on another lane can also be captured. In addition, it can be displayed on the monitor device 16.

Further, in this embodiment, since the direction indicator 13 or the steering angle sensor 14 is used for the lane change detecting means, the sensor and the like need not be separately attached to the vehicle.
The lane changing operation of the vehicle can be sensed using the existing direction indicator 13 or steering angle sensor 14 provided in the vehicle A.

In the embodiment, steps 12 and 13 in the flowchart shown in FIG. 7 are specific examples of the search range expanding means, and steps 19 and 20 are specific examples of the search range returning means. Further, although the scanning angle θ2 of the search wave T and the beam angle β of the search wave T are set to certain values, the present invention is not limited to this, and the search range may be set according to, for example, the vehicle speed.

In the embodiment, when the lane change is detected in the following operation, the beam angle of the search wave T is expanded from α to β, and the scanning angle for swinging the search wave T is changed from θ1 to θ1. Although the search range is expanded by expanding to θ3, the present invention is not limited to this, and the search range may be expanded by expanding only the beam angle of the search wave T.

Further, in the embodiment, the traveling information is described as being composed of three pieces of information of the relative position, the following distance, and the relative speed. However, any one of these pieces of information may be used, or two pieces of information may be used. . Furthermore, information other than these, for example, information such as the size and shape of the preceding vehicle may be used.

In the embodiment, the case where the present invention is used for the automatic speed control has been described as an example. However, it is needless to say that the present invention may be used for the automatic stop control instead.

Further, in the embodiment, the receiving element 9 is
Although the case where two photodiodes are arranged in 2 × 2 has been described, the present invention is not limited to this, and the number of photodiodes is arranged in 2 × 3, 3 × 3, 3 × 4,. In this case, the number of areas can be made larger than in the embodiment.

[0085]

As described above in detail, according to the first aspect of the present invention, when a reflected wave from a preceding vehicle, which is an obstacle, is received by the receiving means, the reflected wave is always received by the follow-up means. By using the scanning means to control the irradiation direction of the exploration wave so that it can be received by the vehicle, it can follow the movement of the preceding vehicle, and can continue to follow the vehicle even when passing through a curve or a sloping road. Is used for the automatic speed control, for example, the speed can be controlled so that the inter-vehicle distance between the own vehicle and the preceding vehicle becomes a predetermined constant inter-vehicle distance, and the riding comfort can be stabilized.

When the lane change detecting means detects the lane change operation, the search range expanding means changes one or both of the scan angle of the search wave by the scanning means and the beam angle of the search wave by the transmission means. By doing so, the search range is expanded, and the preceding vehicle traveling on another lane is captured. As a result, the exploration wave can follow the preceding vehicle after the lane change, and the time required to find and follow the preceding vehicle after moving can be shortened, and the operation can immediately proceed to the following operation.

According to a second aspect of the present invention, the exploration range expanding means includes:
The angle at which the search wave scanned by the scanning means is swung in the left-right direction is widened, and the invention according to claim 3 uses the search range expanding means to irradiate the search wave transmitted by the transmission means forward. Because the configuration was to widen the angle of
The search range by the search wave transmitted from the transmission means can be expanded, and a preceding vehicle within the search range can be captured.

According to the fourth aspect of the present invention, when the vehicle is traveling on the own lane, the following means follows the movement of an obstacle traveling on the own lane. When it is sensed that the change has been completed, the vehicle follows the movement of the obstacle traveling on the destination lane, so when there is a preceding vehicle traveling ahead of the own vehicle, the following means By controlling the scanning means, it is possible to follow the exploration wave according to the movement of the preceding vehicle,
Even when passing through a curve or a slope, the tracking by the exploration wave can be continued.

According to the fifth aspect of the present invention, the lane change detecting means is constituted by the direction indicator or the steering angle sensor for detecting the steering angle of the steering wheel. Therefore, the lane change detecting means is provided on the vehicle without separately attaching the sensor or the like to the vehicle. The lane change of the vehicle can be sensed using an existing turn signal or a steering angle sensor.

According to the sixth aspect of the present invention, the search range returning means for returning the search range expanded by the search range expanding means to the reduction side when the vehicle has completed the lane change is provided. When a preceding vehicle is present, the following operation is performed by the following device, and when there is no preceding vehicle on the destination lane, scanning of the search wave can be performed by the scanning device.

According to the seventh aspect of the present invention, at least one of a relative position, an inter-vehicle distance, and a relative speed between the own vehicle traveling from the reflected wave received by the receiving means and a preceding vehicle traveling ahead of the own vehicle. Is provided as the travel information, the driver can calculate at least one of the relative position, the inter-vehicle distance, and the relative speed between the own vehicle and an obstacle such as a preceding vehicle in the search range. Recognize and drive your car safely. In particular, when changing lanes, using the traveling information of the preceding vehicle traveling on another lane, if the preceding vehicle is traveling in the destination lane, the exploration wave follows the preceding vehicle by the following means. It is possible to quickly shift to the following operation even after the lane change.

According to the eighth aspect of the present invention, since the notifying means for notifying the driving information calculated by the driving information calculating means is provided, the driver can not only drive on the preceding vehicle traveling on the same lane but also on the destination lane. The traveling information of the relative position, the inter-vehicle distance, and the relative speed of the preceding vehicle traveling on the vehicle can be recognized, and the traveling safety of the own vehicle can be improved as compared with the visual confirmation.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing a preceding vehicle detection device according to an embodiment.

FIG. 2 is an explanatory diagram showing a state in which a search wave is transmitted from the own vehicle and a preceding vehicle is scanned.

FIG. 3 is an explanatory diagram showing a beam angle of a search wave.

FIG. 4 is an explanatory diagram of an array of photodiodes of a receiving element as viewed from the front.

FIG. 5 is an explanatory diagram of an area formed by receiving elements as viewed from the front.

FIG. 6 is a flowchart showing a preceding vehicle detection process according to the embodiment.

FIG. 7 is a flowchart showing a preceding vehicle detection process following the flowchart of FIG. 6;

FIG. 8 is a front view of the monitor device showing a state in which a relative position, an inter-vehicle distance, and a relative speed of a preceding vehicle traveling in another lane are displayed.

FIG. 9 is a front view of the monitor device showing a state in which a relative position, an inter-vehicle distance, and a relative speed of a preceding vehicle traveling in the same lane and another lane are displayed.

FIG. 10 is an explanatory diagram showing a state in which a preceding vehicle follows a search wave.

FIG. 11 is an explanatory diagram showing a follow-up state of a search wave when a preceding vehicle is traveling on a curve.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 preceding vehicle detection device (obstacle detection device) 2 search wave transmission unit (transmission unit) 4 transmission element 5 transmission lens 6 lens moving mechanism (scanning unit, search range expansion unit) 7 reflected wave reception unit (reception unit) 11 control Unit 13 Turn indicator (lane change detecting means) 14 Steering angle sensor (lane change detecting means) 16 Monitoring device (notifying means)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G08G 1/16 G08G 1/16 C

Claims (8)

[Claims] 1. A transmitting means for transmitting a search wave forward in a traveling direction of an own vehicle, a scanning means for scanning a search wave transmitted from the transmitting means at least in a left-right direction with respect to a traveling direction, and the scanning. Receiving means for receiving a reflected wave when the search wave scanned by the means is reflected by a forward obstacle, and controlling the scanning means when it is determined that the obstacle is captured from the reflected wave received by the receiving means. Tracking means for following an exploration wave transmitted from the transmitting means in accordance with movement of an obstacle; lane change detecting means for detecting an operation when the vehicle changes lanes; and lane change by the lane change detecting means. When an operation is sensed, the search range is expanded by changing one or both of the scan angle of the search wave by the scanning unit and the beam angle of the search wave by the transmission unit to expand the search range. Obstacle detection device configured as follows. 2. The obstacle detecting device according to claim 1, wherein the search range expanding means is configured to widen an angle when the search wave scanned by the scanning means swings in the left-right direction. 3. The obstacle detecting device according to claim 1, wherein the search range expanding means is configured to widen an angle when the search wave transmitted by the transmitting means is irradiated forward. 4. The following means follows a preceding vehicle traveling on the own lane while traveling on the own lane, and detects that the lane change of the own vehicle has been completed by the lane change detecting means. 4. The obstacle detection device according to claim 1, wherein the obstacle detection device is configured to sometimes follow a preceding vehicle traveling on a destination lane. 5. The lane change sensing means is constituted by a direction indicator operated when the own vehicle changes lanes, or a steering angle sensor for detecting a steering angle of a steering wheel when the own vehicle changes lanes. The obstacle detection device according to claim 1, 2, 3, or 4. 6. A search range return means for returning the search range expanded by the search range expansion means to the reduction side when the lane change detection means detects that the lane change of the own vehicle has been completed. Claims 1, 2, 3,
The obstacle detection device according to 4 or 5. 7. At least one of a relative position, an inter-vehicle distance, and a relative speed between a host vehicle traveling from the reflected wave received by the receiving means and a preceding vehicle traveling in front of the host vehicle as travel information. 7. The obstacle detecting device according to claim 1, further comprising running information calculating means for calculating. 8. The obstacle detecting device according to claim 7, further comprising a notifying unit for notifying the driving information calculated by the driving information calculating unit.