JP2000074655A - Method and device for measuring road-surface roughness distribution - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for measuring a road-surface roughness distribution wherein the partial rough distribution of a road surface is acquired. SOLUTION: A device for measuring a road-surface roughness distribution is provided with an antenna 13 which emits a measurement wave 11 toward a road-surface 12 and receives a scattering wave which is generated when the measurement wave 11 is reflected on the roughness of the road-surface 12 and scattered, rotating means 20 and 21 which rotate the antenna 13 in the plane orthogonal in the emission direction of the measurement wave 11, a transmitting/receiving means 16 which generates and amplifies the measurement wave while amplifies the received scattered wave, a processing means 22a for processing the scattered wave amplified by the transmitting/receiving means 16, a storage means 22B which stores the result of the processing means 22A while related to the rotation angle of the antenna 13, and a parameter formation means 23a wherein the stored content in the storage means 22b is compared with a pre-set content to calculate the compared result for forming a parameter related to a road-surface roughness distribution.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a road surface unevenness distribution measuring apparatus and a measuring method for measuring the distribution of minute unevenness on a road surface by emitting a measurement wave such as a polarized wave composed of a microwave or a millimeter wave. It is about the method.

[0002]

2. Description of the Related Art Fine unevenness on road surface (road surface unevenness distribution)
Has a significant effect on the safe driving of vehicles. In other words, the smaller the road surface, the smaller the frictional resistance to the tire,
It becomes slippery and reduces the driving safety and braking performance of the brake. In recent years, various types of safety support systems have been proposed for safe driving of vehicles. Among them, information on road surface unevenness distribution closely related to slipperiness of the road surface is one of essential factors. One.

Meanwhile, as one of means for measuring the distribution of such road surface irregularities, a scattered wave which radiates a polarized wave composed of a millimeter wave or a microwave to a site to be measured on the road surface and reflects and scatters the reflected waves on the irregularities. Among them, there is known a road surface unevenness distribution measuring device and a measuring method, in which a scattered wave returning to a polarized light source is received, and the intensity of the scattered wave is measured to determine the unevenness distribution state.

FIG. 5 shows a conventional apparatus for measuring the unevenness of the road surface. An antenna 13 that emits the polarized wave 11 is provided on a support 14 standing on the ground. This antenna
13 is in a plane parallel to the emission direction of the polarized wave 11 by an axis 14a parallel to the Y axis.
As shown by, it is provided on the support base 14 so as to be rotatable in the ZX plane.

The antenna 13 has a horizontal direction (FIG. 5).
The antennas 13a and 13b made of conductors extend in the direction parallel to the Y-axis direction and the direction perpendicular to the Z-axis direction (in the direction parallel to the Z-axis direction), and are generated and amplified by the transmission / reception unit 16 connected to the antenna 13. Horizontal and vertical polarizations
a and 13b are fired toward the road surface 12.

The polarized wave 11 emitted from the antenna 13 toward the road surface 12 is reflected and scattered on unevenness of the road surface. Of the scattered waves, the horizontally polarized wave and the vertically polarized scattered wave returned to the antenna 13 are reflected. Are received by the antennas 13a and 13b, respectively. Such transmission / reception operations are performed a plurality of times by changing the angle of the antenna 13 variously between the angles θ1 and θ2 between the emission direction of the polarized wave 11 and the road surface 12.

[0007] The scattered waves received at each angular position of the antenna 13 are amplified by the transmission / reception device 16 and sent to the control device 18 via the communication cable 17. The control device 18 processes the amplified scattered wave and obtains a measurement result of the road surface unevenness in a certain area based on the preset contents.

In this case, the angle θ between the launch direction of the polarized wave 11 and the road surface 12 and the intensity curve of the received scattered wave are measured for the vertically polarized wave and the horizontally polarized wave, and the result is subjected to an inverse estimation process. ,
For example, an input is made to an algorithm process using a neuro to extract parameters related to the unevenness of the road surface 12. In the inverse estimation neural algorithm, when a parameter relating to unevenness is determined, a model formula for radio wave scattering on a random surface is known for the intensity of the scattered wave in that case (for example, in 1994, ARTEKHOU).
"Microwave Scattering and Emission Mode" published by SUE
ls and Their Applications, page 63, Equation 2.3), and using this model equation to create training data for the neuro-algorithm, it is possible to easily perform inverse estimation.

[0009]

However, the above-described conventional apparatus and method for measuring road surface unevenness distribution use the intensity of the scattered wave obtained every time the antenna 13 is rotated by a predetermined angle in the direction of arrow A in FIG. Since the road surface unevenness distribution is obtained, it is not possible to obtain an average height difference from the reference surface of the road surface on which the polarized wave 11 is emitted when the antenna 13 is located at the predetermined angle position. That is, the road surface
There is a disadvantage that only 12 partial unevenness distributions can be obtained. The unevenness of the road surface 12 changes slightly even partially due to snow accumulation, freezing, volume of sand or gravel, etc.
It is not sufficient to obtain the unevenness distribution in only one direction (in this case, only the X direction in FIG. 5).

The present invention has been made in view of the above problems, and provides a measuring apparatus and a measuring method of a road surface unevenness distribution capable of obtaining a partial unevenness distribution of a road surface on which a polarized wave is emitted from an antenna. The purpose is to:

[0011]

According to a first aspect of the present invention, there is provided an apparatus for measuring the unevenness of a road surface, wherein the measuring wave is emitted toward a road surface and the measuring wave is transmitted to the road surface. An antenna for receiving the scattered wave that returns to the emission source of the measurement wave among the scattered waves reflected and scattered by the unevenness, and a rotation unit that rotates the antenna in a plane orthogonal to the emission direction of the measurement wave And transmitting and receiving means for generating and amplifying the measurement wave to be emitted connected to the antenna and amplifying the received scattered wave, and processing means for processing the scattered wave amplified by the transmitting and receiving means,
A storage unit that stores the processing result processed by the processing unit in association with the rotation angle of the antenna, and compares the content stored in the storage unit with a preset setting content, and performs an arithmetic process on the comparison result. And a parameter forming means for forming a parameter relating to the road surface unevenness distribution. With this configuration, since a plurality of measurement waves are emitted at different angles to a part of the road surface, the measurement is performed based on the relationship between the rotation angle position of the antenna and the processing result of the scattered wave for each angle measurement wave. It is possible to obtain a detailed unevenness distribution on a partial road surface where waves are emitted.

According to a second aspect of the present invention, in the first aspect of the invention, the measurement wave is a polarized wave.

According to a third aspect of the present invention, in the second aspect of the invention, the polarized waves emitted from the antenna are two kinds of orthogonal polarized waves. With this configuration, the unevenness distribution can be easily obtained by a known neuro-algorithm process.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the antenna is rotatable in a plane parallel to the emission direction of the measurement wave and perpendicular to the road surface. The rotation driving means is provided. With this configuration, it is possible to obtain a detailed distribution of unevenness in a measurement area of a road surface having a constant width and length.

According to a fifth aspect of the present invention, in the method for measuring a road surface unevenness distribution, a measurement wave is emitted toward a road surface from an antenna positioned at a predetermined rotation angle position in a plane orthogonal to the emission direction of the measurement wave. A step of emitting a measurement wave, a step of receiving a scattered wave in which the measurement wave is reflected and scattered on unevenness of a road surface, a processing step of processing the received scattered wave to obtain a predetermined processing result, and the processing result And a storage step of storing in association with the rotation angle of the antenna that emits the measurement wave, and rotating the antenna by a predetermined angle in a plane perpendicular to the emission direction of the measurement wave, from the emission step to the storage step A parameter for forming a parameter related to road surface unevenness distribution by repeating the antenna rotation step and comparing the content stored in the storage step with the preset setting content, and calculating and processing the comparison result. And it is characterized in that it comprises a data forming process. According to such a method, a plurality of measurement waves can be emitted at different angles with respect to a part of the road surface. Therefore, the measurement is performed based on the relationship between the rotation angle position of the antenna and the processing result of the scattered wave for each measurement wave. It is possible to obtain a detailed unevenness distribution on a partial road surface where waves are emitted.

According to a sixth aspect of the present invention, in the fifth aspect of the invention, the measurement wave is a polarized wave.

According to a seventh aspect of the present invention, in the sixth aspect of the invention, the polarized wave emitted from the antenna is:
It is characterized by two types of orthogonally polarized waves. With this configuration, the unevenness distribution can be easily obtained by a known neuro-algorithm process.

According to an eighth aspect of the present invention, in the invention according to any one of the fifth to seventh aspects, the antenna is rotated in a plane parallel to the direction of emission of the polarized wave and perpendicular to the road surface. The process from the firing step to the parameter forming step is repeated for each rotation angle to obtain a road surface unevenness distribution in a certain area. With such a method, a detailed distribution of unevenness can be obtained in a measurement area of a road surface having a certain width and length.

[0019]

Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic view of an apparatus for measuring a road surface unevenness distribution according to an embodiment of the present invention, and FIG. 2 is a circuit block diagram of the measuring apparatus in this embodiment. In the apparatus for measuring the road surface unevenness distribution shown in FIG. 1, the same members and the same portions as those in the conventional example are denoted by the same reference numerals, and detailed description thereof will be omitted.

An antenna 13 for emitting a polarized wave 11 as a measurement wave
Is mounted on a support base 14 erected on the ground.
In the conventional apparatus for measuring the unevenness of the road surface shown in FIG. 5, the antenna 13 is mounted on the support base 14 so as to be rotatable in a YZ plane parallel to the direction of emission of the polarized light. Are different in that they are fixedly mounted on the support base 14 so that the angle formed by the polarization 11 with respect to the road surface 12 maintains a constant angle θ. On the other hand, in the present invention, the antenna 13 is rotatably mounted on a plane orthogonal to the emission direction of the polarized wave 11. (The direction of rotation of the antenna 13 is indicated by an arrow B in the figure).

That is, the antenna 13 is attached to the transmission / reception device 16 as transmission / reception means via the rotating shaft 20, and is rotated by a predetermined angle by a rotation driving body 21 such as a stepping motor or a servomotor, and positioned at the rotation angle position. It is designed to be fixed. The drive and stop of the rotary drive 21 are performed based on a command signal output from the control device 18. The rotation shaft 20 and the rotation driver 21 constitute a rotation unit that rotates the antenna 13 in a plane perpendicular to the emission direction of the polarized wave 11.

The antenna 13 is a Cassegrain antenna having a focal point on the axis of the rotating shaft 20.
The two antennas 13a and 13b which are orthogonal to the radial direction are extended. In this embodiment, two orthogonal polarizations 11 generated and amplified by the transmission / reception device 16 are transmitted through the antenna 13
a and 13b are directed toward the road surface 12 at a predetermined angle θ.

The transmitting / receiving device 16 has a transmitting unit 19 for generating and amplifying a polarized wave, and a receiving unit 15 for amplifying a received radio wave and transmitting it to a control device 18 as a video signal.
Reference numeral 17 denotes a communication cable for transmitting and receiving various signals between the transmission / reception device 16 and the control device 18. The launch unit
The polarization generated at 19 may be a millimeter wave or a microwave of about 36 G ·, and the output of the antenna 13 may be about 10 mW.

The control unit 18 extracts only scattered waves reflected and scattered on the road surface unevenness distribution from the video signal transmitted from the receiving unit 15, and converts the scattered waves into, for example, a digital signal representing the intensity of the scattered waves. Processing unit as processing means for converting to signals
A signal processing unit 22 comprising a memory 22b as storage means for storing the processing result of the processing unit 22a in association with the rotation angle position of the antenna 13; A memory 23b as storage means for storing a large number of relationships between the rotation angle position and the unevenness distribution of 13; and comparing the processing results stored in the memory 23b with learning contents stored in advance in the memory 23b.
And a data processing unit 23 having an unevenness distribution parameter forming unit 23a as a parameter forming means for estimating the unevenness distribution of the road surface 12 using a known neuro-algorithm process similar to the conventional example.

Next, the method for measuring the road surface unevenness distribution according to the present invention will be described together with the operation of the road surface unevenness distribution measuring apparatus shown in FIGS. FIG. 3 is a flowchart illustrating the method for measuring the road surface unevenness distribution according to the present invention. The emission unit 19 (see FIG. 2) of the transmission / reception device 16 (see FIG. 1) generates and amplifies the polarization to be emitted from the antenna 13 and sends it to the antenna 13 (step S1). Polarization from antennas 13a and 13b of antenna 13
11 is fired toward the road surface 12 (step S2).

At this time, the rotation driver 21 holds the antenna 13 at a predetermined rotation angle position. After transmitting and receiving the polarized wave 11 to the antenna 13 for a certain time, the transmitting and receiving device 16 switches the circuit to the receiving unit 15 side, stops the emission of the polarized wave 11 from the antenna 13, and is reflected and scattered by the unevenness of the road surface 12 Of the scattered waves, the scattered waves that have returned to the antenna 13
a and 13b (step S3).

The receiving unit 15 amplifies the received radio wave and transmits it as a video signal to the signal processing unit 22 (step S).
4). The signal processing unit 22 extracts only the scattered wave reflected and scattered on the road surface unevenness from the video signal in the processing unit 22a, and converts the scattered wave into a digital signal representing the intensity of the scattered wave, for example. The result of the conversion is stored in the memory 22b in association with the rotation angle position of the antenna 13 (step S
5).

Next, after the reception of the scattered wave is completed, the control unit 18
Outputs a command signal to the rotation driver 21, rotates the antenna 13 by a predetermined angle (for example, 15 degrees), and fixes the antenna 13 at the rotation angle position (step S6). Thereafter, the operations of steps S1 to S6 are repeated until the rotation angle of the antenna 13 reaches a predetermined angle (for example, 180 degrees) (step S7).

After all the above operations are completed, the controller 18 compares the processing results stored in the memory 22b with the learning contents stored in the memory 23b of the data processing unit 23 (step S8).

FIG. 4 is a graph showing the processing results (the relationship between the scattered wave intensity data and the rotation angle position of the antenna 13) stored in the memory 22b. As shown in the figure, it can be seen that the data of the intensity σ of the scattered wave and the rotation angle position Φ of the antenna 13 have a fixed relationship. The unevenness distribution parameter forming unit 23a predicts the unevenness distribution of the road surface 12 from the collation result using a neuro algorithm process (step S9). It is desirable that the learning data stored in the memory 23b be as large as possible in order to make the prediction result by the neuro-algorithm process as accurate as possible.

Although one embodiment of the present invention has been described, the present invention is not limited to the above embodiment. For example, in the above embodiment, two orthogonal
Although it has been described that one polarized wave 11 is emitted, only one of the polarized waves 11 may be emitted. Also,
The measurement wave is not limited to the polarization, and may be a light wave having a predetermined wavelength. Further, a rotation drive unit that enables the antenna 13 to rotate in a plane parallel to the emission direction of the polarized wave 11 and perpendicular to the road surface 12 may be provided.

With such a configuration, the antenna 13 is rotated by a predetermined angle in the plane, and the above operation is repeated for each rotation angle position to obtain a partial unevenness distribution on the road surface 12. It is possible to obtain a detailed uneven distribution in a certain area of the road surface 12 having a width and a length.

[0033]

Since the present invention is configured as described above, it is possible to obtain a partial unevenness distribution on the road surface from which the measurement wave is emitted, and it is possible to obtain the road surface due to snow, freezing, volume of sand and gravel, and the like. It is also possible to sufficiently cope with a partial change of the antenna, and by providing a rotation drive means that makes the antenna rotatable in a plane parallel to the emission direction of the measurement wave and perpendicular to the road surface. In addition, there is an effect that a detailed road surface unevenness distribution can be obtained in a region having a certain width and length in addition to the partial unevenness distribution.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing a state at the time of measuring a road surface unevenness distribution according to an embodiment of the present invention.

FIG. 2 is a circuit block diagram of an embodiment of the present invention.

FIG. 3 is a flowchart at the time of measuring a road surface unevenness distribution according to the embodiment of the present invention.

FIG. 4 is a graph showing a relationship between intensity data of scattered waves stored in the memory and a rotation angle position of the antenna.

FIG. 5 is a schematic perspective view of one example of a conventional road surface unevenness distribution measuring device of the same type as the present invention.

[Explanation of symbols]

 11 Measurement wave (Polarized wave) 12 Road surface 13 Antenna 13a, 13b Antenna 14 Support 15 Receiver 17 Communication cable 18 Controller 20 Rotary shaft 21 Rotary driver 22 Signal processor 22a Processor 22b Memory 23 Data processor 23a Roughness distribution Parameter formation unit 23b Memory

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G01S 13/88 G01S 13/88 Z F-term (Reference) 2F067 AA45 CC10 EE04 GG09 HH02 JJ02 KK08 LL02 MM02 NN07 NN08 QQ08 RR00 RR12 RR30 RR44 UU36 2F069 AA60 BB24 DD19 GG04 GG08 GG58 GG63 GG72 GG73 JJ10 JJ26 NN00 NN08 NN13 5J070 AA01 AA14 AC12 AD01 AD05 AD15 AE07 AF01 AH20 AJ13 AK22

Claims (8)

[Claims] An antenna that emits a measurement wave toward a road surface and receives the scattered wave that returns to the emission source of the measurement wave among the scattered waves that are reflected and scattered by the measurement wave on the road surface. Rotating means for rotating the antenna in a plane orthogonal to the emission direction of the measurement wave, transmission and reception means for generating and amplifying the measurement wave to be emitted connected to the antenna and amplifying the received scattered wave, Processing means for processing the scattered wave amplified by the transmitting and receiving means, and storage means for storing the processing result processed by the processing means in association with the rotation angle of the antenna,
Road surface unevenness, comprising: comparing the content stored in the storage means with a preset setting content; and performing arithmetic processing on the comparison result to form a parameter relating to the road surface unevenness distribution. Distribution measuring device. 2. The apparatus according to claim 1, wherein the measurement wave is a polarized wave. 3. The road surface unevenness distribution measuring apparatus according to claim 1, wherein the polarized waves emitted from the antenna are two kinds of orthogonal polarized waves. 4. The apparatus according to claim 1, further comprising: a rotation drive unit that makes the antenna rotatable in a plane parallel to the emission direction of the measurement wave and perpendicular to the road surface. The measuring device for road surface unevenness distribution according to any one of the above. 5. A step of emitting a measurement wave from an antenna positioned at a predetermined rotation angle position in a plane orthogonal to the emission direction of the measurement wave toward a road surface, and A receiving step of receiving a scattered wave that is reflected and scattered; a processing step of processing the received scattered wave to obtain a predetermined processing result; and storing the processing result and the rotation angle position of the antenna in association with each other. And an antenna rotating step of rotating the antenna by a predetermined angle in a plane perpendicular to the emission direction of the measurement wave, repeating the emission step to the storage step at the rotation angle position, and stored in the storage step. A parameter forming step of comparing the content with a preset setting content, and performing an arithmetic processing on the matching result to form a parameter relating to the road surface unevenness distribution. Measurement method of surface unevenness distribution. 6. The method according to claim 5, wherein the measurement wave is a polarized wave. 7. The road surface unevenness distribution measuring apparatus according to claim 6, wherein the polarized waves emitted from the antenna are two kinds of orthogonal polarized waves. 8. The antenna is rotated in a plane parallel to the direction of emission of polarized waves and perpendicular to the road surface, and the process from the launching step to the parameter forming step is repeated for each nuclear rotation angle so as to form a fixed area. The method for measuring a road surface unevenness distribution according to any one of claims 5 to 7, wherein a road surface unevenness distribution is obtained.