JP2003107159A - Axial deviation adjusting device in object detection device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make performable the aiming of an object detection device only by a simple software processing without the necessity of a mechanical aiming mechanism. SOLUTION: As shown in Fig. (A), when an axis Lr in a detection area of an object detection device Sr is deviated downwardly, the detection device is not likely to detect a sign board, etc., at higher positions than a road surface but likely to detect droppings, etc., on the road surface. In this case, a problem of detecting droppings, etc., on the road surface can be solved by lowering the sensitivity for a short distance as shown Fig. 9 (B). In contrast, when the axis Lr is deviated upwardly, there is no possibility to detect droppings, etc., on the road surface but a sign board, etc., at higher positions then the road surface. In this case, a problem of detecting a sign board can be solved by lowering the sensitivity for a long distance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmitting means for transmitting an electromagnetic wave toward a predetermined detection region, a receiving means for receiving a reflected wave in which the electromagnetic wave transmitted by the transmitting means is reflected by an object, and a receiving means. The present invention relates to a vehicle object detection device including an object recognition unit that recognizes an object when the received intensity of a received reflected wave is equal to or higher than a predetermined threshold value, and particularly to a device that adjusts a vertical axis deviation.

[0002]

2. Description of the Related Art When a radar device used for an ACC system (adaptive cruise control system), a Stop & Go system (congestion tracking system), an inter-vehicle warning system, etc. is mounted on a vehicle, the object detection axis of the radar device is previously set. If you do not correctly point in the set direction, the system will not work because it will incorrectly detect an oncoming vehicle in the next lane and will not work, or it will only detect the road surface, overpass, and signboard and not the preceding vehicle. The problem occurs.

Japanese Patent Laid-Open No. 2000-258527 discloses that
The radar device is supported on the stay fixed to the vehicle body through a plurality of bolts so that the angle of the radar device can be adjusted, and the bolt is adjusted so that the deviation angle between the traveling direction of the vehicle and the optical axis of the radar device is less than a predetermined value. It is described that the radar device is rotated to mechanically aim the radar device.

Further, Japanese Patent Laid-Open No. 9-178856 discloses that
When selecting a part of the scanning range of the radar device installed in the vehicle and setting the detection range, set the detection range so that the detection position of the reference reflector by the radar device matches the previously stored reference position. Describes that the aiming is performed by adjusting the direction of the detection range.

[0005]

By the way, the above-mentioned Japanese Patent Application Laid-Open No. 2
The one described in Japanese Patent Application Publication No. 000-258527 requires a mechanical aiming mechanism that supports the radar device for the stay fixed to the vehicle body through a plurality of bolts so that the angle can be adjusted. However, there is a problem in that it is disadvantageous in terms of space, and that it not only takes a lot of time and labor for aiming work, but also the accuracy of aiming work is limited.

Further, although the technique described in Japanese Patent Laid-Open No. 9-178856 can perform aiming by software processing of a computer without the need for a mechanical aiming mechanism, it does not affect the scanning range of the radar device. There has been a problem that the calculation processing for selecting a part and setting the detection range becomes large in scale, and the calculation load of the computer increases.

The present invention has been made in view of the above circumstances, and an object of the present invention is to make it possible to aim an object detecting apparatus by a simple software process without requiring a mechanical aiming mechanism.

[0008]

In order to achieve the above object, according to the invention described in claim 1, a transmitting means for transmitting an electromagnetic wave toward a predetermined detection region, and an electromagnetic wave transmitted by the transmitting means. An object detection device for a vehicle, comprising: receiving means for receiving a reflected wave reflected by an object; and object recognizing means for recognizing the object when the reception intensity of the reflected wave received by the receiving means is equal to or higher than a predetermined threshold value. In, the axis deviation detecting means for detecting the axial deviation of the transmitting means and the receiving means with respect to the vehicle in the vertical direction, and the threshold value for changing the threshold value to compensate the axis deviation when the axis deviation detecting means detects the axis deviation. There is proposed an axis deviation adjusting device in an object detecting device for a vehicle, comprising: a changing unit.

According to the above construction, the receiving means receives the reflected wave in which the electromagnetic wave transmitted by the transmitting means is reflected by the object, and when the receiving intensity of the reflected wave is equal to or higher than a predetermined threshold value, the object recognizing means causes the object to recognize. When the axial deviation detecting means detects the vertical axial deviation of the transmitting means and the receiving means with respect to the vehicle, the threshold changing means changes the threshold so as to compensate for the axial deviation. It is possible to aim the object detection device by a simple software process that merely changes the threshold value without requiring a mechanism.

According to the invention described in claim 2,
In addition to the structure of claim 1, the axis deviation detecting means detects the axis deviation based on a difference in received intensity of reflected waves from at least two reference reflecting objects that are evenly arranged in the vertical direction with respect to the vehicle direction. There is proposed an axis deviation adjusting device in an object detecting device for a vehicle, which is characterized by detecting.

According to the above construction, the axis deviation detecting means detects the axis deviation based on the difference in the reception intensity of the reflected waves from at least two reference reflecting objects arranged evenly in the vertical direction with respect to the direction of the vehicle. Therefore, it is possible to easily and reliably detect the vertical axis deviation.

According to the invention described in claim 3,
In addition to the configuration of claim 1 or claim 2, there is provided a distance calculation means for calculating a distance to an object based on a time difference between a transmission timing by the transmission means and a reception timing by the reception means, and the axis deviation detection means is upward. There is proposed an axis deviation adjusting device in an object detecting device for a vehicle, wherein the threshold value changing means increases the threshold value at a long distance when the axis deviation is detected.

According to the above construction, when the axial deviation detecting means detects the upward axial deviation, the threshold changing means raises the threshold at a long distance, so that a signboard or the like above the road surface is erroneously detected as an object. It can be avoided.

According to the invention described in claim 4,
In addition to the configuration of claim 3, when the axis deviation detecting means detects an upward axis deviation, the threshold changing means increases the threshold at a long distance and lowers the threshold at a short distance. An axis deviation adjusting device in a vehicle object detecting device is proposed.

According to the above arrangement, the threshold value changing means further lowers the threshold value at a short distance, so that the ability to detect an object at a short distance can be enhanced. At this time, since the shaft is in an upwardly offset state, even if the ability to detect an object at a short distance is enhanced, it is possible to avoid erroneously detecting a falling object on the road surface as an object.

According to the invention described in claim 5,
In addition to the configuration of claim 1 or claim 2, a distance calculation means for calculating a distance to an object based on a time difference between a transmission timing by the transmission means and a reception timing by the reception means is provided, and the axis deviation detection means is downward. There is proposed an axis deviation adjusting device in an object detecting device for a vehicle, wherein the threshold value changing means raises the threshold value at a short distance when the axis deviation is detected.

According to the above construction, when the axial deviation detecting means detects the downward axial deviation, the threshold changing means raises the threshold at a short distance, so that a falling object on the road surface is prevented from being erroneously detected as an object. can do.

According to the invention described in claim 6,
In addition to the structure of claim 5, when the axial deviation detecting means detects downward axial deviation, the threshold changing means increases the threshold at a short distance and lowers the threshold at a long distance. An axis deviation adjusting device in a vehicle object detecting device is proposed.

According to the above construction, the threshold value changing means further lowers the threshold value at a long distance, so that the ability to detect an object at a long distance can be enhanced. At this time, since the axis is in the downward axis shift state, it is possible to prevent the signboard or the like above the road surface from being erroneously detected as an object even if the ability to detect an object at a long distance is improved.

According to the invention described in claim 7,
In addition to the configuration according to claim 3 or 5, the axis deviation detecting means is capable of detecting the axis deviation amount, and the threshold value changing means increases the threshold value in proportion to the axis deviation amount. An axis deviation adjusting device in an object detecting device is proposed.

With the above arrangement, the axis deviation detecting means can detect the axis deviation amount, and the threshold value changing means raises the threshold value in proportion to the axis deviation amount detected by the axis deviation detecting means. It is possible to more surely avoid erroneously detecting a signboard or the like or a fallen object on the road surface as an object.

The light transmitting section 1 and the light receiving section 3 of the embodiment correspond to the transmitting means and the receiving means of the present invention, respectively, and the targets 37L and 37R of the embodiment correspond to the reference reflecting object of the present invention.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below based on the embodiments of the present invention shown in the accompanying drawings.

1 to 16 show an embodiment of the present invention. FIG. 1 is a block diagram of an object detecting device, FIG. 2 is a perspective view of the object detecting device, and FIG. 3 is a target detection distance and reception intensity. Of FIG. 4 and the threshold values A and B for determining the target, FIG. 4 is a diagram showing a state in which the detection area is viewed from the side when the threshold value A is adopted, and FIG. 5 is a case where the threshold value B is adopted. FIG. 6 is a diagram showing a state in which the detection area is viewed from the side, FIG. 6 is a graph showing the relationship between the detection distance and the reception intensity of the target, and thresholds C and D for determining the target. FIG. 7 is a case where the threshold C is adopted. Diagram showing the state of the detection area viewed from the side,
FIG. 8 is a diagram showing a state in which the detection region is viewed from the side when the threshold value D is adopted, FIG. 9 is a diagram showing an adjustment method when the axis of the detection region is shifted downward, and FIG. 10 is a diagram showing the detection region. The figure which shows the adjustment method when an axis line is shifted upwards, FIG.
Is a diagram showing the positional relationship between the object detection device and the left and right targets of the target jig, FIG. 12 is a side view of the target jig, FIG. 13 is a view in the direction of arrow 13 of FIG. 12, and FIG. FIG. 15 is a second partial diagram of a flowchart for explaining the operation, and FIG. 16 is a claim correspondence diagram.

As shown in FIGS. 1 and 2, an object detection device S for detecting the distance and direction of an object in front of the vehicle.
r is composed of a light sending unit 1, a light sending scanning unit 2, a light receiving unit 3, and a distance measurement processing unit 5. The light transmitting unit 1 includes a laser diode 11 that integrally includes a light transmitting lens, and a laser diode drive circuit 12 that drives the laser diode 11. The light transmission scanning unit 2 includes a light transmission mirror 13 that reflects the laser output from the laser diode 11.
And a motor 15 for reciprocally rotating the light-transmitting mirror 13 about the vertical axis 14, and a motor drive circuit 16 for controlling the drive of the motor 15. The light-transmitting beam emitted from the light-transmitting mirror 13 has a vertically long and narrow pattern with a limited horizontal width, which reciprocates in the left-right direction at a predetermined cycle to scan an object.

The light receiving section 3 includes a light receiving lens 17, a photodiode 18 for receiving a reflected wave converged by the light receiving lens 17 and converting it into an electric signal, and a light receiving amplifier circuit 19 for amplifying an output signal of the photodiode 18. Prepare

The distance measurement processing unit 5 communicates with the control circuit 24 that controls the laser diode drive circuit 12 and the motor drive circuit 16 and the external ECU 29 such as the ACC system and the Stop & Go system.
A counter circuit 27 for counting the time from the laser light transmission to the light reception, and a central processing unit 28 for calculating the distance to the object and the direction of the object.

Thus, the vertically elongated light-transmitting beam becomes a momentary detection area, and this detection area moves right and left in the entire detection area to scan the object. Then, the distance to the object is detected based on the time from when the light-transmitting beam is sent to when the reflected wave reflected by the object is received, and the instantaneous detection area The direction of the object is detected based on the direction.

FIGS. 4 and 5 show a state in which the detection area of the object detection device Sr is viewed from the side. The shaded lines drawn in the elliptical region with different densities in five levels show the reception intensity of the reflected wave from the target. The darker the shaded region, the stronger the received intensity of the reflected wave. . The intensity of reception of the reflected wave is strongest on the axis Lr of the object detection device Sr, becomes weaker as it goes up and down, and becomes stronger as it gets closer to the object detection device Sr and gets weaker as it goes away from it.

Reference symbols a to j indicate the positions of the ten targets in the detection area and its vicinity. The five short-range targets a to e have the same distance from the object detection device Sr, but the reception intensity thereof is strongest at the target c on the axis Lr of the object detection device Sr, and the targets b and d.
Is next strongest, and targets a and e are weakest. The five long-distance targets f to j have the same distance from the object detection device Sr, but their reception intensity is the same.
The target h on the axis Lr is the strongest, the targets g and i are the strongest, and the targets f and j are the weakest.

The horizontal axis of FIG. 3 indicates the ten targets a to
j represents the distance and the vertical axis represents the reception intensity. Lines A and B are thresholds of reception intensity for detecting an object, and targets a to j whose reception intensity exceeds the threshold A or the threshold B are detected. Even with the same target,
As the distance from the object detection device Sr increases, the reflected wave becomes weaker and the reception intensity decreases. Therefore, the thresholds A and B are set so that the reception intensity decreases as the distance increases.

Threshold value A at which the sensitivity of the object detection device Sr becomes high
Is adopted, eight targets b, c, d, f, g, h, i, j above the threshold A are detected, and two targets a and e below the threshold A are detected. Not detected (see Figure 4). If the threshold B that reduces the sensitivity of the object detection device Sr is adopted, the six targets b above the threshold B,
c, d, g, h, i are detected and are below the threshold B 4
The individual targets a, e, f, j are not detected (see FIG. 5). In this way, by changing the threshold value, the sensitivity with which the object detection device Sr detects the target can be adjusted.

In FIGS. 4 and 5, the axis L of the detection area is shown.
Although the lengths in the r direction are shown as the same for convenience, in actuality, when the threshold value B having low sensitivity is adopted, the length Lr direction of the detection area is larger than that when the threshold value A having high sensitivity is adopted. Is shortened. However, the axis Lr of the detection area
Since the length in the direction of 100 m is practically sufficient, if the length in the direction of the axis Lr of the detection region corresponding to the reference threshold value (threshold value with the highest sensitivity) is set to about 130 m to 140 m, The axis L of the detection area when the threshold is changed
Even if the length in the r direction decreases, the detection area of 100 m can be secured.

The difference between the threshold values A and B shown in FIG. 3 is constant irrespective of the distance in the direction of the axis Lr, but as in the threshold value C of FIG. If it is raised, as shown in FIG.
Only one target c of ~ e is detected, and all five targets f ~ j are detected at a long distance. On the contrary, if the sensitivity at a short distance is made high and the sensitivity at a long distance is made low like the threshold value D in FIG. 6, all the five targets a to e are detected at the short distance as shown in FIG. , And only three targets g, h, i of the five targets f to j are detected at a long distance.

As shown in FIG. 9A, the object detection device S
If the axis Lr of the detection area of r is shifted downward, there is no risk of detecting a signboard or the like at a high position from the road surface, but there is a risk of detecting a fallen object or the like on the road surface. In this case,
By reducing the sensitivity at a short distance, it is possible to eliminate the problem of detecting a fallen object on the road surface, as shown in FIG. 9B. It should be noted that if the sensitivity at a long distance is increased in addition to the sensitivity at a short distance as in the case of the threshold value C described above, the ability to detect an object at a long distance can be enhanced. in this case,
Since the axis Lr is shifted downward, there is no risk of detecting a signboard or the like above the road surface at a long distance.

As shown in FIG. 10 (A), when the axis Lr of the detection area of the object detection device Sr is displaced upward, there is no risk of detecting a fallen object on the road surface, but it is at a high position from the road surface. There is a risk of detecting signs and the like. In this case, by lowering the sensitivity at a long distance, the result shown in FIG.
As shown in, it is possible to solve the problem of detecting a signboard or the like located at a high position from the road surface. The above-mentioned threshold D
As described above, if the sensitivity at a short distance is made high in addition to the sensitivity at a long distance being lowered, the ability to detect an object at a short distance can be enhanced. In this case, since the axis Lr is deviated upward, there is no possibility of detecting a falling object on the road surface at a short distance.

As described above, by simply changing the threshold value for determining the sensitivity of the object detecting device Sr without actually adjusting the direction of the axis Lr of the object detecting device Sr attached to the vehicle, the software of the computer can be simplified. The object detection device Sr can be substantially aiming only by making a simple change, and the cost for providing a mechanical aiming mechanism,
Not only the weight and space are reduced, but also the time required for aiming work can be shortened and the accuracy of aiming work can be improved.

As shown in FIG. 16, the axis deviation adjusting device of the object detecting apparatus Sr includes an object recognizing means M1, an axis deviation detecting means M2, a threshold changing means M3, and a distance calculating means M4.

The object recognition means M1 compares the reception intensity of the reflected wave of the object detection device Sr with a predetermined threshold value and recognizes an object having a reception intensity equal to or higher than the threshold value. The axis deviation detecting means M2 detects an axis deviation of the object detecting device Sr using a target jig 31 for aiming described later. The distance calculation means M4
The distance to the object is detected based on the time from the transmission of the transmission beam of the object detection device Sr to the reception of the reflected wave of the transmission beam reflected by the object. The threshold value changing means M3 changes the threshold value by which the object recognizing means M1 recognizes the object based on the axis deviation state detected by the axis deviation detecting means M2 and the distance to the object calculated by the distance calculating means M4. The object recognition means M1 is caused to aim the object detection device Sr.

Next, the object detection device Sr by changing the threshold value
The aiming method will be specifically described.

As shown in FIGS. 11 to 13, a target jig 31 for aiming is a support column 3 which is erected on a base 32.
3, a pair of targets 37L and 37R composed of reflectors are provided at both ends of an arm 36 rotatably provided on the lifting member 34 via a horizontal rotation shaft 35. To be Target 3
The reflector shapes of 7L and 37R can be arbitrarily selected such as a quadrangle or a circle.

When the object detecting device Sr is mounted on the axis Lv of the vehicle, the target jig 31 having the above structure is used.
Is installed at a position 5 m forward of the extension of the axis Lv,
The height of the rotary shaft 35 is the same as the height of the axis Lv 65.
The height of the elevating member 34 is adjusted to be 0 mm. The left side target 37L is the left side 6 of the vehicle axis Lv.
00 mm, the upper side 150 mm, the right side target 37R is 600 mm on the right side of the vehicle axis Lv, and the lower side 150
The rotational position of the arm 36 is adjusted so that the arm 36 is positioned at mm. Assuming that the object detection device Sr is mounted at a correct angle with respect to the vehicle, the axis Lv of the vehicle and the axis Lr of the object detection device Sr match, and the pair of left and right targets 37L and 37R are set to the object by the above setting. The center position of the detection area of the detection device Sr (that is, the object detection device Sr
(The position of the axis line Lr) of FIG.

Next, the procedure of the aiming work of the object detection device Sr will be described with reference to FIGS. 14 and 15.

First, in step S1, a vertical aiming mode for aiming the object detecting device Sr in the vertical direction is selected, and in step S2, the object detecting device Sr operates to detect the targets 37L and 37R of the target jig 31.
At this time, the number of targets detected in step S5 is two, the distance of the target is within a predetermined range in step S7, the width of the target is within a predetermined range in step S9, and the left and right sides of the target in step S11. If the position is within the predetermined range and the target is stopped in step S13, it is determined that the setting of the vehicle and the target jig 31 is normal, and the process proceeds to step S17.

If the number of targets detected in step S5 is not two, a target number error code is output in step S6. If the target distance is not within the predetermined range in step S7, the target distance is determined in step S8. If an error code is output and the target width is not within the predetermined range in step S9, the target width error code is output in step S10, and the target width error code is output in step S1.
If the left / right position of the target is not within the predetermined range in step 1, the target left / right position error code is output in step S12, and if the target is not stopped in step S13, the target movement error code is output in step S14. Also, the correction of the setting of the target jig 31 is prompted.

When the setting of the vehicle and the target jig 31 is normal, the reflection level (reception intensity) of the left target 37L is calculated in step S17, and the reflection level (reception intensity) of the right target 37R is calculated in step S18. To calculate. The reflection level is calculated as any of 15 levels. Then, in step S19, the reflection level of the left target 37L is higher than the reflection level of the right target 37R, and step S2
If 0 is “reflection level difference> 1”, it is determined in step S21 that the axis Lr of the object detection device Sr is pointing above the axis Lv of the vehicle, and the subsequent steps S22 to S22.
At 28, correction is performed by changing the threshold value.

That is, in step S22, "reflection level difference≤≤
If it is "4", the threshold at a long distance is increased by one step in step S23. If "the reflection level difference ≤ 8" at step S24, the threshold at a long distance is increased by two steps in step S25, and "step S26" is performed. If the reflection level difference ≦ 12 ”, the threshold at long distance is increased by 3 steps in step S27, and step S26 is performed.
If “difference in reflection level> 12”, the threshold value at a long distance is increased by 4 steps in step S28. In this way, when the axis Lr of the object detection device Sr is pointing upwards above the axis Lv of the vehicle, the threshold value at a long distance is increased to reduce the sensitivity, so that the signboard located at a high position from the road surface. It is possible to solve the problem of detecting the like.

On the other hand, if the reflection level of the left side target 37L is less than or equal to the reflection level of the right side target 37R in step S19, and if "reflection level difference <-1" in step S29, then in step S30 the object detecting device is detected. It is determined that the axis line Lr of Sr is lower than the axis line Lv of the vehicle, and the correction by changing the threshold value is executed in the subsequent steps S31 to S37.

That is, in step S31, "reflection level difference ≥
-4 ", the short-range threshold is set to 1 in step S32.
Step up, if "reflection level difference ≥ -8" in step S33, step up the threshold at a short distance by 2 steps in step S34, and if "reflection level difference ≥ -12" in step S35, close in step S36. The threshold for distance is increased by 3 steps, and if the "reflection level difference <-12" in step S35, the threshold for long distance is increased by 4 steps in step S37. In this way, when the axis Lr of the object detection device Sr is directed downward from the axis Lv of the vehicle, the threshold value at a short distance is increased to reduce the sensitivity to detect a falling object on the road surface. It is possible to eliminate the trouble.

Then, in step S20, "reflection level difference≤≤
1 ”or“ reflection level difference ≧ − ”in step S29.
When it becomes "1", the aiming of the object detection device Sr is terminated.

As a concrete method for changing the threshold value, the following various modes can be considered. The threshold value at a predetermined distance (for example, a short distance is 5 m to 30 m and a long distance is 50 m to 90 m) is uniformly increased or decreased. The number of threshold value tables corresponding to the distances is set, and the threshold value is increased or decreased based on the table corresponding to the reflection level difference. The threshold value (the threshold value A) serving as a reference is calculated by adding a coefficient (function of level difference and distance), and the threshold value is changed from a short distance to a long distance.

Although a detailed description of the procedure of the aiming work in the left-right direction of the object detection device Sr is omitted, the object is located at the center position in the left-right direction of the pair of left and right targets 37L, 37R detected by the object detection device Sr. Detector S
The axis Lr of r may be aligned.

Although the embodiments of the present invention have been described in detail above, the present invention can be modified in various ways without departing from the scope of the invention.

For example, although the object detection device Sr of the embodiment uses a laser radar, a millimeter wave radar may be used.

Further, the structure of the target jig 31 is not limited to that of the embodiment, and the target may be provided on the two columns whose left-right intervals can be adjusted so that the targets can be vertically adjusted.

Further, in the embodiment, the threshold value is changed according to the magnitude of the axis deviation amount, but the threshold value may be changed by detecting only the presence or absence of the axis deviation. In this case, if the axis deviation does not disappear with one adjustment, the adjustment may be repeated until the axis deviation disappears.

[0057]

As described above, according to the invention described in claim 1, the receiving means receives the reflected wave in which the electromagnetic wave transmitted by the transmitting means is reflected by the object, and the receiving intensity of the reflected wave is predetermined. When the object recognizing means recognizes an object when it is equal to or more than the threshold value of, when the axial deviation detecting means detects an axial deviation of the transmitting means and the receiving means with respect to the vehicle in the vertical direction,
Since the threshold value changing unit changes the threshold value so as to compensate for the axis deviation, it is possible to aim the object detection device by a simple software process that only changes the threshold value without requiring a mechanical aiming mechanism. It will be possible.

According to the invention described in claim 2,
Since the axis deviation detecting means detects the axis deviation based on the difference in the reception intensity of the reflected waves from at least two reference reflecting objects evenly arranged in the vertical direction with respect to the direction of the vehicle, the axis deviation in the vertical direction is detected. It can be detected easily and reliably.

According to the invention described in claim 3,
When the axis deviation detecting means detects an upward axis deviation, the threshold value changing means raises the threshold value at a long distance, so that a signboard or the like above the road surface can be prevented from being erroneously detected as an object.

According to the invention described in claim 4,
Further, since the threshold value changing means lowers the threshold value at a short distance, the ability to detect an object at a short distance can be improved. At this time, since the shaft is in an upwardly offset state, even if the ability to detect an object at a short distance is enhanced, it is possible to avoid erroneously detecting a falling object on the road surface as an object.

According to the invention described in claim 5,
When the axis deviation detecting means detects the downward axis deviation, the threshold value changing means raises the threshold value at a short distance, so that it is possible to avoid erroneously detecting a falling object on the road surface as an object.

According to the invention described in claim 6,
Further, since the threshold value changing means lowers the threshold value in a long distance, it is possible to enhance the ability to detect an object in a long distance. At this time, since the axis is in the downward axis shift state, it is possible to prevent the signboard or the like above the road surface from being erroneously detected as an object even if the ability to detect an object at a long distance is improved.

According to the invention described in claim 7,
The axis deviation detection means can detect the axis deviation amount, and the threshold value changing means raises the threshold value in proportion to the axis deviation amount detected by the axis deviation detection means. It is possible to more reliably avoid erroneous detection as an object.

[Brief description of drawings]

FIG. 1 is a block diagram of an object detection device.

FIG. 2 is a perspective view of an object detection device.

FIG. 3 is a graph showing a relationship between a target detection distance and a reception intensity, and thresholds A and B for determining a target.

FIG. 4 is a view showing a state in which a detection area is viewed from a side when a threshold value A is adopted.

FIG. 5 is a diagram showing a state in which a detection area is viewed from a side when a threshold B is adopted.

FIG. 6 is a graph showing a relationship between a target detection distance and a reception intensity, and thresholds C and D for determining a target.

FIG. 7 is a diagram showing a state in which a detection area is viewed from a side when a threshold C is adopted.

FIG. 8 is a diagram showing a state in which a detection region when a threshold D is adopted is viewed from the side.

FIG. 9 is a diagram showing an adjustment method when the axis of the detection area is shifted downward.

FIG. 10 is a diagram showing an adjustment method when the axis of the detection area is shifted upward.

FIG. 11 is a diagram showing a positional relationship between the object detection device and the right and left targets of the target jig.

FIG. 12: Side view of target jig

FIG. 13 is a view in the direction of arrow 13 in FIG.

FIG. 14 is a first partial diagram of a flowchart for explaining the operation.

FIG. 15 is a second partial diagram of a flowchart for explaining the operation.

FIG. 16: Claim correspondence diagram

[Explanation of symbols]

1 Light transmitter (transmitting means) 3 Light receiving part (reception means) 37L target (reference reflective object) 37R target (reference reflective object) M1 object recognition means M2 Axis deviation detection means M3 threshold change means M4 distance calculation means

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G08G 1/16 G01S 17/88 AF term (reference) 5H180 AA01 CC03 CC07 CC14 CC30 LL01 LL04 5J070 AB24 AC02 AD02 AE01 AF03 AH14 AK02 AK22 5J084 AA05 AB01 AC02 AD01 BA01 BA04 BA11 BA36 BB02 BB04 BB21 CA25 CA31 CA53 EA04 EA07

Claims (7)

[Claims] 1. A transmitting means (1) for transmitting an electromagnetic wave toward a predetermined detection area, and a receiving means (3) for receiving a reflected wave of the electromagnetic wave transmitted by the transmitting means (1) reflected by an object.
And an object recognition means (M1) for recognizing an object when the reception intensity of the reflected wave received by the reception means (3) is equal to or higher than a predetermined threshold, the transmission means for the vehicle ( 1) and the axis shift detecting means (M2) for detecting the axis shift in the vertical direction of the receiving means (3) and the axis shift detecting means (M2) for compensating for the axis shift when the axis shift is detected. An axis deviation adjusting device in an object detecting device for a vehicle, comprising: a threshold changing means (M3) for changing a threshold. 2. The axis deviation detecting means (M2) is based on a difference in reception intensity of reflected waves from at least two reference reflecting objects (37L, 37R) arranged vertically above and below the vehicle direction. The axis deviation adjusting device in the object detecting device for a vehicle according to claim 1, wherein the axis deviation is detected. 3. A distance calculation means (M) for calculating a distance to an object based on a time difference between a transmission timing of the transmission means (1) and a reception timing of the reception means (3).
4. The method according to claim 1, further comprising 4), wherein when the axial deviation detecting means (M2) detects an upward axial deviation, the threshold value changing means (M3) raises the threshold value at a long distance. 2. The axis deviation adjustment device in the vehicle object detection device according to item 2. 4. The threshold value changing means (M3) increases the threshold value at a long distance and lowers the threshold value at a short distance when the axis deviation detecting means (M2) detects an upward axis deviation. The axis deviation adjusting device in the vehicle object detecting device according to claim 3. 5. A distance calculation means (M) for calculating a distance to an object based on a time difference between a transmission timing of the transmission means (1) and a reception timing of the reception means (3).
4. The method according to claim 1, further comprising 4), wherein the threshold value changing means (M3) raises the threshold value at a short distance when the axis deviation detecting means (M2) detects a downward axis deviation. 2. The axis deviation adjustment device in the vehicle object detection device according to item 2. 6. The threshold value changing means (M3) increases the threshold value at a short distance and lowers the threshold value at a long distance when the axis deviation detecting means (M2) detects a downward axis deviation. The axis deviation adjusting device in the vehicle object detecting device according to claim 5. 7. The axis deviation detecting means (M2) is capable of detecting the axis deviation amount, and the threshold value changing means (M3) raises the threshold value in proportion to the axis deviation amount. An axis deviation adjusting device in the vehicle object detecting device according to claim 5.