JP2024066260A - measuring device - Google Patents

Abstract

[Problem] The amount of deflection of a road surface is measured on a moving vehicle. [Solution] The measurement device includes a plurality of measurement units arranged in front of and behind the vehicle in the traveling direction, each of which measures the shape of the road surface by a light cutting method while the vehicle is moving, one measurement unit measuring the road surface in a loaded state and the other measurement units measuring the road surface in an unloaded state, and a calculation unit that calculates the difference between the measurement results by the plurality of measurement units as the amount of deflection. [Selected Figure] Figure 1

Description

The present invention relates to a measuring device.

Damage to pavement is assessed based on two aspects: the surface condition (road surface properties) and the strength of the structure (soundness). For soundness, deflection measurements using FWD are commonly used to assess (estimate) the amount of instantaneous deflection of the road surface by dropping a weight on it.

A method of measuring road surfaces using a moving vehicle is also known. For example, a device is known in which an optical cutting method imaging means captures images along the longitudinal direction of a roadway via a road surface imaging means, and a road surface profile generating means generates corrected image information by correcting the inclination of the captured image information using the inclination information based on the captured image information, inclination information, and movement information, and then arranges the corrected image information using the movement information, identifies vertical movement information of the road surface imaging means from the image content of the overlapping area, cuts out a part of the corrected image information to generate extracted image information, and corrects the height of the corrected image using the vertical movement information from the corrected image information, sequentially arranges the extracted image information, and combines them to generate a road surface profile (Patent Document 1).

WO2014/170989

The deflection measurement using the FWD mentioned above is an evaluation at a specific point, and it is not possible to measure continuously in the direction of travel on the road. In addition, since the measurement must be performed in a stationary state, there are issues such as lane restrictions.

In the above-mentioned Patent Document 1, measurements based on the light-section method are performed on a moving vehicle, but there is no disclosure of measuring the amount of deflection of the road surface.

Therefore, the objective of the present invention is to measure the amount of deflection of the road surface while a vehicle is moving.

The first aspect of the present invention is a measuring device that is attached to a vehicle, the measuring device including a plurality of measuring units arranged at the front and rear of the vehicle in the traveling direction, each measuring unit measuring the shape of the road surface by a light cutting method while the vehicle is traveling, one measuring unit measuring the road surface in a loaded state and the other measuring units measuring the road surface in an unloaded state, and a calculation unit that calculates the difference between the measurement results by the plurality of measuring units as the amount of deflection.

In the second aspect of the present invention, in the first aspect, the calculation unit obtains values for the positions of the wheels on the outside line side of the road surface and the wheels on the center line side from profile data representing relative height obtained from the measurement results by the measurement unit that measures the road surface in an unloaded state, obtains values for the positions of the wheels on the outside line side of the road surface and the wheels on the center line side from the profile data obtained from the measurement results by the measurement unit that measures the road surface in a loaded state, calculates a time interval from the traveling speed and the installation interval of the measurement devices, calculates the difference in values for the positions of the wheels on the outside line side of the road surface and the wheels on the center line side during the time interval as the deflection amount, and records the positioning results by the positioning device that measures the position of the vehicle in association with the deflection amount.

In a third aspect of the present invention, in the first or second aspect, the measurement unit measures the shape of the road surface by photographing a marker formed on the road surface by irradiation with a slit laser oscillator from an oblique direction.

The present invention makes it possible to measure the amount of deflection of the road surface while the vehicle is moving.

FIG. 2 is a functional block diagram showing a measurement device. FIG. 2 is a side view of a vehicle in which some components of the measuring device are incorporated. FIG. 1 is a perspective view illustrating a light-section method applied to an embodiment. FIG. 4 is a functional block diagram showing a calculation unit of the measurement device. 4 is a flowchart showing a measurement processing routine performed by the measurement device. FIG. 13 is a diagram showing an example of a deflection curve representing continuously calculated deflection amounts;

Below, an embodiment of the measuring device according to the present invention will be described with reference to the drawings.

(Configuration of the measuring device)
FIG. 1 is a functional block diagram showing a measurement device 100.

Figure 2 is a side view of a vehicle 1 in which some of the components of the measuring device 100 are incorporated.

The measuring device 100 is composed of a first measuring unit 2A, a second measuring unit 2B-1, 2B-2 provided in the vehicle 1, a positioning unit 11, a detection unit 12, and each functional unit provided outside the vehicle 1. Each functional unit provided outside the vehicle 1 is composed of a control unit 10, a calculation unit 13, a memory unit 101, a display unit 102, and an input unit 103. The control unit 10, the calculation unit 13, the memory unit 101, the display unit 102, and the input unit 103 are composed of hardware and software of a personal computer.

The control unit 10 controls each process carried out within the personal computer.

The data measured by the first measurement unit 2A provided in the vehicle 1, the data measured by the second measurement units 2B-1 and 2B-2, the data measured by the positioning unit 11, and the data detected by the detection unit 12 are input to the personal computer via a storage medium or via information communication means such as the Internet. Note that an embodiment in which some or all of the control unit 10, calculation unit 13, storage unit 101, display unit 102, and input unit 103 are mounted on the vehicle 1 is also possible.

Vehicle 1 is a work vehicle based on a work truck used, for example, for road maintenance work.

The first measuring unit 2A is provided on the bottom surface of the vehicle 1 forward of the rear wheels (e.g., the bottom surface of the center between the front wheels (two axles) and the rear wheels) so as to face the road surface 4.

The second measuring units 2B-1 and 2B-2 are installed on the underside of the front and rear wheels of the vehicle 1 so as to face the road surface 4.

The first measurement unit 2A photographs the markers formed on the road surface by irradiation with a slit laser oscillator from an oblique direction to measure the shape of the road surface in an unloaded state. Specifically, the first measurement unit 2A measures the height of each position in the traveling direction of the road surface 4 for the wheels OWP on the outer line side of the road surface 4 and the wheels IWP on the center line side. The height of each position in the traveling direction of the road surface 4 is obtained using the light cutting method. Here, the "road surface in an unloaded state" refers to a road surface outside the range of influence of the wheel load stress caused by the wheels.

The second measurement units 2B-1 and 2B-2 photograph markers formed on the road surface by irradiation with a slit laser oscillator from an oblique direction for each position of the wheel OWP on the outer line side of the road surface 4 and the wheel IWP on the center line side, and measure the shape of the road surface in a loaded state. Specifically, the second measurement unit 2B measures the height of each position in the traveling direction of the road surface 4 before and after the ground contact position of the rear wheel for each position of the wheel OWP on the outer line side of the road surface 4 and the wheel IWP on the center line side. The height of each position in the traveling direction of the road surface 4 is obtained using the light cutting method. Here, the "road surface in a loaded state" refers to a road surface that has been deformed by the wheel load stress caused by the wheels.

Specifically, the first measurement unit 2A includes a first slit laser oscillator 21A and a first image capture unit 22A.

Figure 3 is a perspective view illustrating the light-section method applied to the embodiment.

The first slit laser oscillator 21A oscillates a slit laser. The first slit laser oscillator 21A is attached to the vehicle 1 so that it can irradiate the road surface from above with a slit-shaped slit laser that is parallel to the traveling direction 41 of the vehicle 1. A linear marker 42 that is parallel to the traveling direction of the road surface is formed on the road surface by the irradiation of the slit laser.

The first imaging unit 22A is attached to the vehicle 1 so that it can capture images from an oblique direction relative to the road surface, so that the linear marker 42 fits within the imaging area.

Therefore, according to the principle of the light-section method, if the road surface is flat along the road travel direction, the first image capture unit 22A captures the linear marker 42 as a straight line, and if the road surface is uneven along the road travel direction, the first image capture unit 22A captures the linear marker 42 as a distorted line with unevenness.

The second measurement unit 2B, like the first measurement unit 2A, is configured to include a second slit laser oscillator 21B and a second image capture unit 22B. The second slit laser oscillator 21B and the second image capture unit 22B have the same configuration as the first slit laser oscillator 21A and the first image capture unit 22A, so a description thereof will be omitted.

The positioning unit 11 measures the traveling position of the vehicle 1, for example, using a GPS (Global Positioning System).

The detection unit 12 detects the traveling speed of the vehicle 1, for example, using a vehicle speed sensor.

The calculation unit 13 calculates the difference between the measurement results by the first measurement unit 2A and the second measurement unit 2B as the amount of deflection.

Specifically, as shown in FIG. 4, the calculation unit 13 includes a profile measurement unit 131, a value acquisition unit 132, a difference calculation unit 133, a recording unit 134, and an evaluation unit 135.

The profile measurement unit 131 generates profile data representing the relative height of each position on the road surface in the direction of travel based on data obtained by photographing the linear markers 42 using the first measurement unit 2A. The profile measurement unit 131 also generates profile data representing the relative height of each position on the road surface in the direction of travel based on data obtained by photographing the linear markers 42 using the second measurement units 2B-1 and 2B-2.

Specifically, as described below, relative vertical movement information in the direction of travel of the first image capture unit 22A is generated from each captured image, which serves as material for generating the road surface profile.

First, the images captured by the first image capture unit 22A are corrected to images captured from a specific, predetermined angle using tilt information from the first image capture unit 22A, thereby correcting each captured image to a state in which it was captured from a reference angle.

The relative height displacement in the traveling direction of the first image capturing unit 22A that captured the correction image is calculated from the positional deviation in the direction perpendicular to the traveling direction of each position of the marker 42 included in the correction image, and relative vertical movement information in the traveling direction of the first image capturing unit 22A is generated.

Then, the relative vertical movement information in the direction of travel of the first imaging unit 22A generated from each captured image is sequentially arranged and combined to generate profile data.

In addition, as described below, relative vertical movement information in the direction of travel of the second image capture unit 22B is generated from each captured image, which serves as material for generating the road surface profile.

First, the images captured by the second image capturing unit 22B-1 and the second image capturing unit 22B-2 are corrected to a corrected image captured from a predetermined specific angle using the tilt information of the second image capturing unit 22B-1 and the second image capturing unit 22B-2, thereby correcting each captured image to a state in which it was captured from a reference angle. In addition, a connected corrected image is generated by connecting the corrected images of the second image capturing unit 22B-1 and the second image capturing unit 22B-2.

The relative height displacement in the traveling direction of the second image capturing units 22B-1 and 22B-2 that captured the combined correction image is calculated from the positional deviation in the traveling direction of each position of the marker 42 included in the combined correction image in the direction perpendicular to the traveling direction, and relative vertical movement information in the traveling direction of the second image capturing units 22B-1 and 22B-2 is generated.

Then, the relative vertical movement information in the direction of travel of the second imaging unit 22B-1 and the second imaging unit 22B-2 generated from each captured image is sequentially arranged and combined to generate profile data.

The value acquisition unit 132 acquires profile data obtained by shape measurement using the light cutting method in the first measurement unit 2A, which measures the road surface that is not loaded, for each position of the wheels OWP on the outer line side of the road surface and the wheels IWP on the center line side.

In addition, the value acquisition unit 132 acquires profile data obtained by shape measurement using the light cutting method in the second measurement unit 2B, which measures the road surface in a loaded state, for each position of the wheels OWP on the outer line side of the road surface and the wheels IWP on the center line side.

The difference calculation unit 133 calculates a time interval from the traveling speed detected by the detection unit 12 and the distance between the first measurement unit 2A and the second measurement unit 2B, and calculates the difference between the two profile data for the position of the wheel OWP on the outer line side of the road surface as the amount of deflection during that time interval, and calculates the difference between the two profile data for the position of the wheel IWP as the amount of deflection.

The recording unit 134 records the amount of deflection calculated for each position of the wheels OWP on the outer side of the road surface and the wheels IWP on the center line side in the memory unit 101, linking it to the GPS positioning results.

As a result, the deflection amount calculated continuously for each position (each measurement line) of the wheel OWP on the outer side line of the road surface and the wheel IWP on the center line side is stored in the memory unit 101.

The evaluation unit 135 calculates an evaluation value of the pavement soundness from a deflection curve that represents the amount of deflection calculated continuously for each position (each measurement line) of the wheels OWP on the outer side line of the road surface and the wheels IWP on the center line side of the road surface. For example, the evaluation value is calculated so that the more locations where the amount of deflection is equal to or greater than a threshold, the lower the pavement soundness.

(Operation of the measuring device)
Next, the operation of the measuring device 100 will be described with reference to FIG.

First, a vehicle 1 equipped with the measuring device 100, specifically, for example, a patrol vehicle used for daily patrol work, is driven on a road surface 4, and an instruction to start measurement is given via the input unit 103.

When measurement begins, the first measurement unit 2A photographs the markers 42 formed on the road surface by irradiation from the first slit laser oscillator 21A from an oblique direction at each time, measures the shape of the road surface, and stores the results in the memory unit 101.

The second measurement unit 2B photographs the marker 42 formed on the road surface by irradiation from the second slit laser oscillator 21B from an oblique direction at each time, measures the shape of the road surface, and stores the results in the memory unit 101.

The positioning unit 11 measures the traveling position of the vehicle 1 at each time, for example, using GPS (Global Positioning System), and stores the position in the memory unit 101.

The detection unit 12 detects the traveling speed of the vehicle 1 for each time, for example, using a vehicle speed sensor, and stores the detected speed in the memory unit 101.

The profile measurement unit 131 generates profile data representing the relative height of each position in the direction of travel on the road surface for each position of the wheels OWP on the outer line side of the road surface 4 and the wheels IWP on the center line side at each time based on the data of the linear markers 42 photographed by the first measurement unit 2A, and stores the data in the memory unit 101.

The profile measurement unit 131 also generates profile data representing the relative height of each position in the direction of travel on the road surface for each position of the wheels OWP on the outer line side of the road surface 4 and the wheels IWP on the center line side of the road surface 4 at each time based on the data of the linear markers 42 photographed by the second measurement unit 2B, and stores the data in the memory unit 101.

Then, the measurement device 100 executes the measurement process shown in FIG. 6.

In step S100, the value acquisition unit 132 acquires profile data generated for each position of the wheels OWP on the outer line side of the road surface 4 and the wheels IWP on the center line side of the road surface 4 for the first measurement unit 2A.

In step S102, the value acquisition unit 132 acquires profile data generated for each position of the wheels OWP on the outer line side of the road surface 4 and the wheels IWP on the center line side of the road surface 4 for the second measurement unit 2B.

In step S104, the value acquisition unit 132 acquires the traveling position of the vehicle 1 at each time.

In step S106, the difference calculation unit 133 calculates the time interval for each time from the driving speed and the interval between the first measurement unit 2A and the second measurement unit 2B.

In step S108, the difference calculation unit 133 calculates the difference between the two profile data for the position of the wheel OWP on the outer line side of the road surface as the amount of deflection for each time at the time interval calculated in step S106 above, and calculates the difference between the two profile data for the position of the wheel IWP as the amount of deflection.

In step S110, the recording unit 134 records the deflection amount calculated for each position of the wheel OWP on the outer side line of the road surface and the wheel IWP on the center line side for each time in the memory unit 101, linking it to the GPS positioning results.

In step S112, the evaluation unit 135 calculates an evaluation value of the pavement soundness from the deflection curve representing the deflection amount calculated continuously for each position (each measurement line) of the wheel OWP on the outer line side of the road surface and the wheel IWP on the center line side, displays it on the display unit 102, and ends the measurement process. For example, as shown in FIG. 6, the evaluation value is calculated so that the more points where the deflection amount is equal to or greater than the threshold, the lower the pavement soundness. FIG. 6 shows an example in which the deflection curve representing the deflection amount calculated continuously for the wheel OWP on the outer line side of the road surface has points where the deflection amount is large, and the evaluation value of the pavement soundness of the road surface is calculated to be low.

As described above, according to the measuring device 100 of this embodiment, one measuring unit arranged at the front and rear of the vehicle in the traveling direction measures the road surface in a loaded state, and the other measuring unit measures the road surface not in a loaded state, and the difference between the measurement results by the measuring units is calculated as the amount of deflection, thereby making it possible to measure the amount of deflection of the road surface while the vehicle is moving.

The present invention is not limited to the above-described embodiment, and various modifications and applications are possible without departing from the spirit of the invention.

1 Vehicle 2A First measurement unit 2B Second measurement unit 4 Road surface 10 Control unit 11 Positioning unit 12 Detection unit 13 Calculation unit 21A First slit laser oscillator 21B Second slit laser oscillator 22A First imaging unit 22B Second imaging unit 42 Marker 100 Measurement device 101 Memory unit 131 Profile measurement unit 132 Value acquisition unit 133 Difference calculation unit 134 Recording unit 135 Evaluation unit

Claims (4)

In a measuring device mounted on a vehicle,
A plurality of measurement units are arranged in front of and behind the vehicle in the traveling direction, each of which measures the shape of a road surface by a light cutting method while the vehicle is traveling, one measurement unit measures the road surface in a loaded state, and the other measurement units measure the road surface in an unloaded state;
A calculation unit that calculates a difference between the measurement results by the plurality of measurement units as a deflection amount;
A measuring device comprising: The measuring device according to claim 1, wherein the one measuring unit is disposed in front of and behind the rear wheel of the vehicle, and measures the shape of the road surface in front of and behind the ground contact position of the rear wheel. The calculation unit is
From the measurement results by the measurement unit that measures the road surface in an unloaded state, profile data is obtained that represents the relative heights of the wheels on the outer line side of the road surface and the wheels on the center line side of the road surface;
From the measurement results of a measurement unit that measures a road surface under a load, the profile data is obtained for each position of the wheels on the outer line side of the road surface and the wheels on the center line side of the road surface;
a time interval is calculated from the traveling speed and the installation interval of the measuring devices, and a difference in the profile data for the position of the wheel on the outer line side of the road surface and a difference in the profile data for the position of the wheel on the center line side of the road surface are calculated as the deflection amount during the time interval;
2. The measuring device according to claim 1, wherein the amount of deflection is recorded in association with a positioning result obtained by a positioning device that measures the position of the vehicle. 4. The measuring device according to claim 1, wherein the measuring unit measures the shape of the road surface by photographing a marker formed on the road surface by irradiation with a slit laser oscillator from an oblique direction.