JP2000314775A - Distance measuring equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To precisely discriminate whether it is a vehicle or a delineator, or discriminate among the vehicle, the delineator and a signboard. SOLUTION: Two separated section areas where photoreceiving intensity in every detection section by a laser radar range-finding part 10 for scanning horizontally a laser beam to measure a distance upto front-side object every plural detection sections is a prescribed value or more are detected, the two objects are determined to exist in parallel when luminescent intensity in a section between the two section areas reaches the maximum value, as a result instructed to intensify the luminescent intensity of the section between the two section areas to emit the laser beam, and the existence of a preceding vehicle is determined when the intensity does not reach the maximum value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a distance measuring device.

[0002]

2. Description of the Related Art Conventionally, as an apparatus for scanning an irradiation direction of a laser radar in a horizontal direction and detecting a position of an object based on a received light intensity and an irradiation angle, one disclosed in JP-A-9-264954 is disclosed. There is.

[0003]

However, the laser beam is strongly reflected by a roadside delineator and a reflector at the rear of the vehicle in front of the vehicle. However, the reflection of a vehicle body, especially a dark-colored body, is extremely small. When two separated strong reflection light receiving regions are detected, it is difficult to determine whether the light receiving region is a roadside delineator or a vehicle rear reflector.

The present invention has been made in view of such a conventional problem, and is capable of accurately determining whether a vehicle is a vehicle, a delineator, or a vehicle, a delineator, or a sign. It is an object of the present invention to provide a distance measuring device that can be performed well.

[0005]

According to the first aspect of the present invention, there is provided a distance measuring apparatus which scans a laser beam in a horizontal direction to form a plurality of detection sections. A laser radar distance measuring means for measuring a distance to a forward object every time, and detecting whether or not a light receiving intensity of each detection section by the laser radar distance measuring means is equal to or more than a predetermined value, and separating the two by a predetermined value or more. Detecting the partitioned area,
Control means for repeatedly instructing the laser radar ranging means to emit light with an increased light emission intensity of the section between the two section areas; and a light emission intensity of the section between the two section areas reaching a maximum value. It is characterized by having a preceding vehicle determining means for determining whether or not the preceding vehicle has been reached and, when the maximum value has not been reached, determining that the vehicle is a preceding vehicle.

According to a second aspect of the present invention, in the distance measuring apparatus according to the first aspect, the control means further includes a control unit for determining that all the light receiving intensities are lower than the predetermined value. When the light emission intensity of the vehicle reaches a maximum value, an instruction is given to make a determination by the preceding vehicle determining means.

A distance measuring apparatus according to a third aspect of the present invention is a laser radar distance measuring means for scanning a laser beam in a horizontal direction to measure a distance to a forward object for each of a plurality of detection sections. Detecting whether the received light intensity of each detection section by the laser radar distance measuring means is equal to or more than a predetermined value,
A control unit that detects two separated partitioned areas that are equal to or greater than a predetermined value, and repeats instructing the laser radar ranging unit to emit light with an increased emission intensity of the partitioned area between the two partitioned areas; It is characterized by having a delineator determining means for determining whether or not the luminous intensity of a section between two partitioned areas has reached a maximum value, and when reaching the maximum value, determining as a delineator.

According to a fourth aspect of the present invention, in the distance measuring apparatus according to the third aspect of the present invention, the control means may further include: all the sections for which the received light intensity is determined to be lower than the predetermined value. When the light emission intensity of the light source reaches the maximum value, an instruction is given to make a judgment by the delineator judgment means.

According to a fifth aspect of the present invention, there is provided a distance measuring apparatus, comprising: a laser radar distance measuring means for scanning a laser beam in a horizontal direction to measure a distance to a forward object for each of a plurality of detection sections. Detecting whether the received light intensity of each detection section by the laser radar distance measuring means is equal to or more than a predetermined value,
Control means for repeatedly detecting two separated divided areas which are equal to or more than a predetermined value and instructing the laser radar distance measuring means to emit light with increased light emission intensity of the divided area between the two divided areas; Calculating means for calculating the difference between the received light intensity and the emitted light intensity for each; range determining means for determining whether the value of the difference is one of three ranges, large, medium, and small; A front object determining unit that determines whether the vehicle is a preceding vehicle, a delineator, or a signboard by determining whether the vehicle is ahead or away from the vehicle.

According to a sixth aspect of the present invention, in the distance measuring apparatus according to the fifth aspect, the control means further comprises: all the sections for which the received light intensity is determined to be lower than the predetermined value. When the light emission intensity of the target object reaches a maximum value, an instruction is given to make a judgment by the front object judgment means.

According to a seventh aspect of the present invention, there is provided a distance measuring apparatus, comprising: a laser radar distance measuring means for scanning a laser beam in a horizontal direction to measure a distance to a forward object for each of a plurality of detection sections. Detecting whether the received light intensity of each detection section by the laser radar distance measuring means is equal to or more than a predetermined value,
Control means for repeatedly detecting two separated divided areas which are equal to or more than a predetermined value and instructing the laser radar distance measuring means to emit light with increased light emission intensity of the divided area between the two divided areas; Calculating a difference between the received light intensity and the emitted light intensity for each of the second predetermined values in which sections in which the difference is larger than a first predetermined value are continuous and the difference is larger than the first predetermined value; When a larger section is separated, a preceding vehicle determining means for determining a preceding vehicle is provided.

[0012] Further, an eighth invention according to claim 8 is characterized in that:
In the distance measuring apparatus according to a seventh aspect of the present invention, the control means further includes: when the light emission intensities of all the sections for which the light reception intensity is determined to be lower than the predetermined value become the maximum value, the preceding vehicle determination means. Instructing to make a determination based on

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a distance measuring device according to the present invention will be described below in detail with reference to the accompanying drawings.

(First Embodiment) FIG. 1 is a block diagram of a first embodiment of a distance measuring apparatus according to the present invention. First, the configuration will be described. Reference numeral 10 denotes a laser radar ranging unit having a scanning mechanism, which is arranged at the front of the vehicle such as a bumper and irradiates a pulsed laser beam toward the front of the vehicle and scans the irradiation direction in the horizontal direction. Then, a scanning angle is detected, and a distance is calculated for each scanning angle based on a time from a light transmission time to a light reception time to output distance data.

Reference numeral 20 denotes an arithmetic unit which outputs a distance measurement start command to the laser radar distance measurement unit 10, inputs distance data for each scanning angle from the laser radar distance measurement unit 10, and issues an alarm instruction. And a travel control command to a travel actuator 40 such as a throttle valve actuator or a brake actuator.

The calculation unit 20 includes an input / output circuit 21 connected to the laser radar distance measurement unit 10, an input / output circuit 22 connected to the notification unit 30 and the actuator 40, a RAM 23, and an RO.
M24 and CPU 25, each of which is a bus 26
Connected through.

Next, based on FIG. 2 and FIG.
The measurement routine executed by the CPU 25 will be described. FIG. 2 is a flowchart of the measurement routine, and FIG. 3 is an explanatory diagram of the processing contents of FIG. 3A shows a case where a preceding vehicle is present in front of the own vehicle (50 is a reflector in the figure), and FIG. This is an example in the case where the delineator 60 exists.

First, the measurement routine shown in FIG. 2 starts every predetermined time. Step S101 is initialization.
The light transmission intensity level Sn is set to 5. Where the argument n
Sets the horizontal irradiation range to 8 according to the scanning angle.
This is a section number when divided into 0, and setting the light transmission intensity level Sn to 5 means that the light transmission intensity levels of the sections 1 to 80 are all set to 5. The light transmission intensity level Sn is an intermediate value between 0 and 10.

In step S102, the laser radar distance measuring section 10 gives the section number n (1 to 80) and the light transmission intensity level Sn set in step S101 corresponding to the section number n.
By outputting (n = 1 to 80), the laser radar ranging unit 10 emits pulsed laser light at the scanning angle corresponding to the section number n (see FIG.
1), (a-2)).

In step S103, the light transmission intensity level Sn
Is received, and the received light intensity level Rn
(N = 1 to 80) are stored in the RAM 23 (see FIG.
2), (b-2)).

Step S104 is initialization, in which zero is set as the initial value of the counter CNT, zero is set as the light transmission flag Fsn, and 1 is set as the section number n.

In step S105, the received light intensity level Rn
It is determined whether (at first, R1) is equal to or less than a predetermined value Rth and the flag Fsn is zero. Here, the predetermined value Rth is a value by which the reflector or the delineator can be distinguished from the vehicle body or the signboard by the light receiving intensity level, and is set to 5 in this example.

The processing of steps S106 to S108 is performed for the section of YES in step S105, and the section number n is 80 in step S109 of the section of NO.
Is determined.

In step S106, the light transmission intensity level S
The value (= 6) obtained by adding 1 to 1 (= 5) is set as S1, and the next light transmission intensity level S1 is set (FIG. 3 (a-3), (b-
3)), if Sn is 10 or more in step S107,
Set Sn = 10 and set the flag Fsn to 1,
In step S108, the value of the counter CNT is increased by one.

That is, when it is determined that the light is not a reflector or a delineator based on the received light intensity level (YES in step S105), the light transmission intensity level S1 is increased by one, and if there is a possibility that the light is a reflector or a delineator, the transmission is performed. Without changing the value of the light intensity level S1, the process is repeated until the section number n becomes 80 (steps S110 and S11).
1).

If it is determined in step S110 that the section number n has become 80, that is, the next scan is performed in accordance with the received light intensity level Rn corresponding to the 80 section numbers in one horizontal scan. Transmission intensity level Sn
Is determined, the counter CN is determined in step S111.
It is determined whether T is zero.

In the case of NO in step S111, that is, when the scanning is performed once in the horizontal direction, the light receiving intensity level R
There is at least one section in which n is equal to or less than a predetermined value Rth, and all the light transmission intensity levels Sn of the section are 10
If not, the process returns to step S102 to output the updated light transmission intensity level Sn.

As shown in FIG. 3 (a-4), when the reflector of the laser beam is the preceding vehicle, the light receiving intensity level is increased by increasing the light transmitting intensity level of the section having the low light receiving intensity level. It rises, but does not rise in the case of the delineator (FIG. 3 (b-4)). In the case of the preceding vehicle, by further increasing the light transmission intensity level of the section having the low light reception intensity level (FIG. 3A-5), the light reception intensity level eventually reaches the predetermined value Rth (FIG. 3A). (A-
6)), in the case of the delineator, even if the light transmission intensity level is further increased (FIG. 3 (b-5)), the light reception intensity level Rn does not change (FIG. 3 (b-6)). Then, by further increasing the light transmission intensity level Sn, the light transmission intensity level Sn of the section corresponding to the portion where the object does not exist reaches the maximum value of 10.

If YES in step S111, that is, if the light transmission intensity levels Sn of all the sections where the light reception intensity level Rn is equal to or less than the predetermined value Rth have become 10, this routine is terminated and the recognition routine is completed. Start.

As described above, in the measurement routine, when scanning in the horizontal direction, the received light intensity level Rn is set to the predetermined value Rth.
If there is at least one of the following sections, and all the light transmission intensity levels Sn of the section have become 10, the processing shifts to the recognition routine.

The recognition routine will be described with reference to FIG. With the end of the routine in FIG. 2 as a trigger,
Start.

In step S201, the light transmission intensity level Sn
The light transmission intensity level Sn of the section between the sections having the lowest is 10
Is determined.

If it is not 10, the light transmission intensity level Sn
However, since an object exists at a position in front of the vehicle corresponding to the section between the lowest sections, it is determined that the vehicle is the preceding vehicle (step S202), and the distance to the preceding vehicle is used, for example,
In order to notify the driver when the distance to the preceding vehicle is equal to or less than a predetermined value, a command is output to a notifying unit 3 such as a buzzer, or the vehicle can follow the preceding vehicle while keeping the distance to the preceding vehicle constant. The torque control value is output to an actuator 4 such as a throttle actuator or a brake actuator.

If YES in step S201,
Since there is no object at a position in front of the vehicle corresponding to the section between the sections having the lowest light transmission intensity level Sn, it is determined that the object is a delineator (step S203), and the distance to the object is smaller than a predetermined value. Is also a delineator
Since it is not an obstacle during the travel of the vehicle, no notification is given.

As described above, according to the first embodiment, the detection section by the laser radar distance measuring section 10 that scans the laser beam in the horizontal direction and measures the distance to the front object for each of the plurality of detection sections. As a result of detecting two spaced-apart regions in which the received light intensity of each of the regions is equal to or more than a predetermined value, and instructing to emit laser light by increasing the light emission intensity of the region between the two-regions, a result is obtained. When the light emission intensity of the section of the vehicle reaches the maximum value, it is determined that two objects are present side by side, and when the light emission intensity does not reach the maximum value, it is determined that the vehicle is a preceding vehicle. It is possible to accurately determine whether the object ahead of the vehicle is a vehicle or a non-vehicle.

(Second Embodiment) Next, a second embodiment of the distance measuring apparatus according to the present invention will be described. The configuration shown in FIG. 1 and the measurement routine shown in FIG.
Since the third embodiment is the same as the first embodiment, a description thereof will be omitted, and a different part of the recognition routine will be described with reference to FIGS.

First, in step S301 in FIG. 5, a value Xn obtained by subtracting the light transmission intensity level Sn from the light reception intensity level Rn.
Ask for. The difference Xn takes a large value when reflected by a reflector or a delineator at the rear of the preceding vehicle, takes a medium value for the body or signboard of the preceding vehicle, and takes a small value when no object exists, By providing a threshold value between each of them, the preceding vehicle, the delineator, the signboard, and the absence of an object are determined. 3 (a-4), (b-
According to 7), in the case of a delineator or a reflector, Xn = 7
−5 = 2, and Xn = 5−7 = −
2 and Xn = 0-10 = −10 when there is no object. Here, the first threshold Xth1 is set to −3, and the second threshold Xth2 is set to 1. 6A shows a case of a preceding vehicle, FIG. 6B shows a case of a delineator, and FIG. 6C shows a case of a signboard.

In step S302, it is determined whether or not the difference Xn is equal to or greater than a first threshold value Xth1, and if NO in all sections, it is determined that no object exists (step S302).
303). Here, the first threshold value Xth1 is set to -3.

If YES in any of the sections in step S302, it is determined in step S304 whether or not the sections whose difference Xn is equal to or greater than the first threshold value Xth1 form a continuous integrated area.

In step S305, the difference Xn is set to the second threshold value Xth2 in the continuous integrated region.
It is determined whether or not it is smaller, and if YES, it is determined to be a signboard (step S306).

If NO in step S305, the difference Xn is set to the second threshold Xth in step S307.
It is determined whether or not two or more sections are continuous integrated areas. If it is determined that the sections are separated, it is determined that the vehicle is a preceding vehicle (step S308).

If NO in step S304, that is,
If the difference Xn is equal to or larger than the first threshold value Xth1, but those sections are separated, the difference Xn is determined in step S309.
If it is determined that there is a section where n is equal to or greater than the second threshold value Xth2, it is determined that the section is a delineator (step S3).
10).

This routine is terminated when it is determined that there is no object, the preceding vehicle, or the delineator, or when there is an unexpected situation such as YES in step S307 and NO in step S309.

According to the second embodiment, the received light intensity of each detection section by the laser radar distance measuring section 10 for scanning the laser beam in the horizontal direction and measuring the distance to the front object for each of the plurality of detection sections is measured. Detecting two separated section areas that are equal to or more than a predetermined value, instructing to increase the emission intensity of the section between the two section areas to emit laser light, and,
By comparing the value obtained by subtracting the light transmission intensity level Sn from the light reception intensity level Rn and two predetermined values, it is possible to distinguish not only the preceding vehicle and the delinator but also the signboard and the like.

[0045]

As described above in detail, according to the present invention, in particular, in the first or seventh invention, the preceding vehicle can be accurately determined, and in the third invention, the delineator can be accurately determined. it can. Further, in the fifth invention, there is an effect that the preceding vehicle, the delineator, and the signboard can be accurately distinguished. According to the second, fourth, sixth or eighth invention,
The accuracy of the determination can be further improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a first embodiment of a distance measuring device according to the present invention.

FIG. 2 is a flowchart of a measurement routine.

3A and 3B are explanatory diagrams of the processing contents of FIG. 2; FIG. 3A shows a case where a preceding vehicle exists in front of the host vehicle; FIG. This is an example of a case where a delineator exists.

FIG. 4 is a flowchart of a recognition routine according to the first embodiment.

FIG. 5 is a flowchart of a recognition routine according to the first embodiment.

6 is an explanatory diagram of the processing content of FIG. 5, (a) is a preceding vehicle,
(B) shows the case of a delineator, and (c) shows the case of a signboard.

[Description of Signs] 10 Laser radar ranging unit 20 Operation unit 21, 22 Input / output circuit 23 RAM 24 ROM 25 CPU 26 Bus 30 Notification unit 40 Actuator

Claims (8)

[Claims] 1. A laser radar distance measuring means for scanning a laser beam in a horizontal direction to measure a distance to an object in front of each of a plurality of detection sections, and a light receiving intensity of each of the detection sections by the laser radar distance measuring means is predetermined. Detects whether or not the distance is equal to or greater than a predetermined value, detects two separated divided areas that are equal to or greater than a predetermined value, and instructs the laser radar distance measuring means to increase the light emission intensity of the divided area between the two divided areas. A control unit that repeats the process of determining whether or not the light emission intensity of the section between the two section areas has reached a maximum value. A distance measuring device, comprising: vehicle determination means. 2. The distance measuring device according to claim 1, wherein the control unit further includes: a light-emitting element configured to determine whether a light-emitting intensity of all the sections determined to have a light-receiving intensity lower than the predetermined value becomes a maximum value. A distance measuring device for giving an instruction to make a determination by the preceding vehicle determining means. 3. A laser radar distance measuring means for scanning a laser beam in a horizontal direction to measure a distance to an object in front of each of a plurality of detection sections, and a light receiving intensity of each detection section by the laser radar distance measuring means is predetermined. Detects whether or not the distance is equal to or greater than a predetermined value, detects two separated divided areas that are equal to or greater than a predetermined value, and instructs the laser radar distance measuring means to increase the light emission intensity of the divided area between the two divided areas. Control means for repeating the operation, and determining whether or not the luminous intensity of the section between the two partitioned areas has reached a maximum value, and when reaching the maximum value, determining that the luminous intensity is a delineator. A distance measuring device, comprising: 4. The distance measuring device according to claim 3, wherein said control means further comprises: when the light emission intensities of all the sections for which the light reception intensity is determined to be lower than said predetermined value become the maximum value. A distance measuring device for giving an instruction to make a judgment by the delineator judging means. 5. A laser radar distance measuring means for scanning a laser beam in a horizontal direction to measure a distance to an object in front of each of a plurality of detection sections, and a light receiving intensity of each detection section by said laser radar distance measuring means is predetermined. Detects whether or not the distance is equal to or greater than a predetermined value, detects two separated divided areas that are equal to or greater than a predetermined value, and instructs the laser radar distance measuring means to increase the light emission intensity of the divided area between the two divided areas. Control means for calculating the difference between the received light intensity and the emitted light intensity for each section; and range determining means for determining whether the value of the difference is one of three ranges, large, medium, and small. In the range, by determining whether the sections are continuous or separated from each other, a preceding object determining means for determining whether the vehicle is a preceding vehicle, a delineator or a signboard, Distance measurement apparatus according to symptoms. 6. The distance measuring device according to claim 5, wherein the control unit further includes a control unit that determines whether the luminous intensities of all the sections for which the received light intensity is determined to be lower than the predetermined value become the maximum value. A distance measuring device for giving an instruction to make a judgment by the front object judging means. 7. A laser radar distance measuring means for scanning a laser beam in a horizontal direction to measure a distance to an object ahead in each of a plurality of detection sections, and a light receiving intensity of each of the detection sections by the laser radar distance measuring means is predetermined. Detects whether or not the distance is equal to or greater than a predetermined value, detects two separated divided areas that are equal to or greater than a predetermined value, and instructs the laser radar distance measuring means to increase the light emission intensity of the divided area between the two divided areas. And a calculating means for calculating the difference between the received light intensity and the emitted light intensity for each section, wherein the sections in which the difference is greater than a first predetermined value are continuous, and the difference is equal to the first section. A preceding vehicle determining means for determining a preceding vehicle when a section larger than a second predetermined value that is larger than a second predetermined value is separated; 8. The distance measuring device according to claim 7, wherein said control means further comprises: when the light emission intensities of all the sections for which the light reception intensity is determined to be lower than said predetermined value become the maximum value. A distance measuring device for giving an instruction to make a determination by the preceding vehicle determining means.