JP2022038917A - Vehicle weight measuring device and vehicle weight measuring method - Google Patents

Abstract

To provide a vehicle weight measuring device that can more accurately measure the weight of a vehicle traveling on a structure.SOLUTION: A vehicle weight measuring device includes: a displacement amount calculation unit that calculates the amount of displacement of a structure based on an image obtained by an imaging unit photographing a grating pattern provided on the structure; an axle information generation unit that generates axle information including entry time at which the axles of the vehicle enter the structure and exit time at which the axles of the vehicle exit from the structure; and a vehicle weight calculation unit that calculates the weight of the vehicle based on the calculated amount of displacement of the structure, the generated axle information, and influence line data indicating displacement at respective points of the structure when a reference vehicle travels on the structure.SELECTED DRAWING: Figure 9

Description

The present invention relates to a vehicle weight measuring device and a vehicle weight measuring method.

In Patent Document 1, among the image data in which the image pickup unit captures and outputs a plurality of grid patterns provided on the measurement object at predetermined time intervals, each image in a plurality of image processing areas in which the grid pattern is reflected is shown. A measuring device for calculating the displacement of the grid pattern between two time points is described for the data. According to this measuring device, the movement of an object to be measured such as a bridge girder of a bridge can be easily measured.

JP-A-2015-141151A

However, the measuring device described in Patent Document 1 cannot grasp what kind of vehicle is passing through the bridge, and cannot accurately measure the vehicle weight.

One aspect of the vehicle weight measuring device according to the present invention is
A displacement amount calculation unit that calculates the displacement amount of the structure based on an image obtained by capturing a grid pattern provided on the structure by the imaging unit.
An axle information generation unit that generates axle information including an approach time in which each axle of a vehicle enters the structure and an exit time in which each axle of the vehicle exits the structure.
The weight of the vehicle is calculated based on the calculated displacement amount of the structure, the generated axle information, and the influence line data indicating the displacement of each point of the structure when the reference vehicle travels on the structure. Vehicle weight calculation unit and
including.

One aspect of the vehicle weight measuring method according to the present invention is
The imaging unit calculates the displacement amount of the structure based on the image obtained by capturing the grid pattern provided on the structure.
Axle information including the approach time when each axle of the vehicle enters the structure and the exit time when each axle of the vehicle exits the structure is generated.
The weight of the vehicle is calculated based on the calculated displacement amount of the structure, the generated axle information, and the influence line data indicating the displacement of each point of the structure when the reference vehicle travels on the structure. do.

The figure for demonstrating the outline of the vehicle weight measuring system using the vehicle weight measuring apparatus of 1st Embodiment. The figure which shows an example of a grid pattern. The figure which shows the other example of a grid pattern. The figure for demonstrating the principle of displacement measurement using a grid pattern. The figure for demonstrating the principle of displacement measurement using a grid pattern. The figure which shows an example of influence line data. Explanatory drawing of WIM. The figure which shows the example of the vehicle of 4 axes. The figure which shows the structural example of the vehicle weight measuring apparatus of 1st Embodiment. The flowchart which shows the procedure of the vehicle weight measurement method of 1st Embodiment. The flowchart which shows the procedure of the displacement amount calculation process. The figure for demonstrating the outline of the vehicle weight measuring system using the vehicle weight measuring apparatus of 2nd Embodiment. The figure which shows the structural example of the vehicle weight measuring apparatus of 2nd Embodiment. The flowchart which shows the procedure of the vehicle weight measurement method of 2nd Embodiment. The figure for demonstrating the outline of the vehicle weight measuring system using the vehicle weight measuring apparatus of 3rd Embodiment. The figure which shows the structural example of the vehicle weight measuring apparatus of 3rd Embodiment. The flowchart which shows the procedure of the vehicle weight measurement method of 3rd Embodiment. The figure for demonstrating the outline of the vehicle weight measuring system using the vehicle weight measuring apparatus of 4th Embodiment. The figure which shows an example of the acceleration detected at the time of entering and leaving a vehicle. The figure which converted the acceleration amplitude of each time of FIG. 19 into acceleration intensity. The figure which binarized the acceleration intensity of FIG. 20 with a predetermined threshold value. The figure which slides the pattern of the exit time with respect to FIG. The figure which shows the structural example of the vehicle weight measuring apparatus of 4th Embodiment. The flowchart which shows the procedure of the vehicle weight measurement method of 4th Embodiment. The figure for demonstrating the outline of the vehicle weight measuring system using the vehicle weight measuring apparatus of 5th Embodiment. The figure which shows the structural example of the vehicle weight measuring apparatus of 5th Embodiment. The flowchart which shows the procedure of the vehicle weight measurement method of 5th Embodiment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The embodiments described below do not unreasonably limit the content of the present invention described in the claims. Moreover, not all of the configurations described below are essential constituent requirements of the present invention.

1. 1. First Embodiment 1-1. Outline of a Vehicle Weight Measuring System Using a Vehicle Weight Measuring Device FIG. 1 is a diagram for explaining an outline of a vehicle weight measuring system using the vehicle weight measuring device 1 of the first embodiment. The vehicle weight measuring device 1 measures the weight of the vehicle 7 traveling on the bridge, which is the structure 4.

As shown in FIG. 1, the grid pattern 3 is arranged on the surface of the structure 4. For example, the grid pattern 3 is arranged near the central portion of the structure 4 in the direction in which the vehicle 7 travels. The grid pattern 3 may be placed on the surface of the structure 4 by affixing, printing, or projecting the grid pattern 3 to the surface of the structure 4. Further, the lattice pattern 3 may be arranged on the surface of the structure 4 by processing the surface of the structure 4.

The image pickup unit 2 has an image pickup element such as a CCD (Charge-Coupled Device) image sensor, and the image pickup element generates an image corresponding to the light incident from the grid pattern 3 or the like arranged in the structure 4. The image pickup unit 2 may be, for example, a digital camera. The image pickup unit 2 may be included in the vehicle weight measuring device 1.

When the vehicle 7 travels on the structure 4, the structure 4 bends and is displaced. The vehicle weight measuring device 1 calculates the displacement amount of the structure 4 based on the image obtained by the imaging unit 2 taking the grid pattern 3.

FIG. 2 is a diagram showing an example of the grid pattern 3. In the grid pattern 3 shown in FIG. 2, black regions are arranged at a constant pitch d in the x and y directions orthogonal to each other, and the region between any two black regions is white. In other words, the grid pattern 3 is a two-dimensional grid pattern in which white grids are arranged at a pitch d in the x-direction and the y-direction. Further, the luminance of the grid pattern 3 changes in a sinusoidal shape with the pitch d as a period in the x-direction and the y-direction.

FIG. 3 is a diagram showing another example of the grid pattern 3. The grid pattern 3 may be a one-dimensional grid pattern in which black regions and white regions are alternately arranged at a constant pitch in one direction as in P1 to P4 of FIG. Further, the grid pattern 3 may be a two-dimensional grid pattern in which square or round black regions are arranged at a constant pitch in two directions between white regions as shown in P5 and P7 of FIG. Further, the grid pattern 3 may be a two-dimensional grid pattern in which white regions are arranged at a constant pitch in two directions as shown in P6 and P8 of FIG. Further, the grid pattern 3 may be a pattern having a rectangular wave-like luminance distribution at a constant pitch, as in P1, P2, P5 to P8 in FIG. Alternatively, the grid pattern 3 may be a pattern having a sinusoidal luminance distribution at a constant pitch, as in P3 and P4 of FIG.

In the present embodiment, the vehicle weight measuring device 1 acquires an image in which the image pickup unit 2 captures the grid pattern 3. Then, the vehicle weight measuring device 1 generates a plurality of moire fringe images for the grid pattern 3 by the sampling moire method based on the acquired images. Further, the vehicle weight measuring device 1 generates a phase distribution of moire fringes by a phase shift method based on a plurality of generated moire fringe images with respect to the grid pattern 3, and obtains a phase distribution of moire fringes of the grid pattern 3. Based on this, the amount of displacement of the structure 4 is calculated.

Further, in the vehicle weight measuring device 1, the image pickup unit 2 enters the structure 4, and each axle of the vehicle 7 enters the structure 4 based on an image obtained by photographing the vehicle 7 exiting the structure 4. Generates axle information including the time and the exit time for each axle of the vehicle 7 to exit the structure 4.

Then, the vehicle weight measuring device 1 is based on the calculated displacement amount of the structure 4, the generated axle information, and the influence line data indicating the displacement of each point of the structure 4 when the reference vehicle travels on the structure 4. Then, the weight of the vehicle 7 is calculated. Specifically, the vehicle weight measuring device 1 calculates the weight of the vehicle 7 by WIM (Weigh-In-Motion) described later. The reference vehicle is a vehicle whose weight is known in advance.

1-2. Principle of displacement measurement using a grid pattern The principle of displacement measurement using a grid pattern 3 will be described with reference to FIGS. 4 and 5.

FIG. 4 is a diagram showing a process of generating a phase distribution of moire fringes of the grid pattern 3 when the displacement of the portion of the structure 4 in which the grid pattern 3 is arranged is zero. In FIG. 4, the dots in (a) indicate the positions of the pixels of the image of the grid pattern 3 included in the image information generated by the image pickup unit 2. Here, it is assumed that the image pickup unit 2 captures an image of the grid pattern 3 having 52 pixels in the x direction in the horizontal direction and 3 pixels in the y direction in the vertical direction. (B) shows the grid pattern 3.

(C) is an image of the grid pattern 3 of (b). When the lattice pattern 3 has a luminance distribution that changes in a sinusoidal shape for each pitch in the x direction, the luminance value of the image in (c) also changes in a sinusoidal shape for each pitch in the x direction. Further, even when the lattice pattern 3 has a luminance distribution that changes in a rectangular wave shape for each pitch in the x direction, the luminance value of each pixel is the luminance value of a plurality of pixels around it depending on the characteristics of the image sensor possessed by the image pickup unit 2. Since it is an integrated image, the luminance value of the image in (c) changes in a pseudo-sine wave shape for each pitch in the x direction. In (b), the grid pattern 3 is a one-dimensional grid pattern in which grids are arranged in the x direction, but when the grid pattern 3 is a two-dimensional grid pattern, the image of the grid pattern 3 is smoothed in the y direction. , (C), an image of a one-dimensional grid pattern in which grids are arranged in the x direction can be obtained.

(D) is a thinned-out image obtained by thinning out the pixels of the other three rows with respect to the image of (c), leaving one row of pixels every four rows from the pixels of the first row in the x direction. (E) is a thinned-out image obtained by thinning out the pixels of the other three rows with respect to the image of (c), leaving one row of pixels every four rows from the pixels of the second row in the x direction. (F) is a thinned-out image obtained by thinning out the pixels of the other three rows with respect to the image of (c), leaving one row of pixels every four rows from the pixels of the third row in the x direction. (G) is a thinned-out image obtained by thinning out the pixels of the other three rows with respect to the image of (c), leaving one row of pixels every four rows from the pixels of the fourth row in the x direction.

(H) is a moire fringe image obtained by smoothing the thinned image of (d) and interpolating the thinned pixels. (I) is a moire fringe image obtained by smoothing the thinned image of (e) and interpolating the thinned pixels. (J) is a moire fringe image obtained by smoothing the thinned image of (f) and interpolating the thinned pixels. (K) is a moire fringe image obtained by smoothing the thinned image of (g) and interpolating the thinned pixels.

In this way, four moire fringe images (h) to (k) can be obtained from the image (c) by the sampling moire method. The moire fringe images of (h) to (k) each have a sinusoidal luminance value in the x direction, and their phases differ by π / 2.

(L) is a moire fringe image obtained by averaging the luminance values of each pixel of the four moire fringe images (h) to (k).

Generally, the luminance value of the coordinates (x, y) in the nth moire fringe image among the N moire fringe images having different phases by 2π / N is expressed by the equation (1). N is an integer of 2 or more, and n is any integer of 0 or more and N-1 or less. In the equation (1), I _a (x, y) is the luminance amplitude of the moire fringes, and I _b (x, y) is the background luminance. As shown in FIG. 4, when the four moire fringe images of (h) to (k) can be obtained from the image of (c), in the formula (1), N = 4, n = 0,1,2, As 3, the brightness values I ₀ (x, y), I ₁ (x, y), I ₂ (x, y), and I ₃ (x, y) of the four moire fringe images are calculated.

The phase distribution of moiré fringes is generated by the phase shift method based on N moiré fringe images. That is, the phase of the moire fringes at the coordinates (x, y) is calculated by the equation (2) using the luminance values of the coordinates (x, y) in the N moire fringe images represented by the equation (1). To.

In FIG. 4, the phase θ (x, y) of the moire fringes in the moire fringe image of (l) is set to N = 4, and the luminance values of the four moire fringe images in the equation (2) are I ₀ (x, y), I. It is calculated by substituting ₁ (x, y), I ₂ (x, y), and I ₃ (x, y). The phase θ (x, y) is a value from −π to π that is periodically repeated. The smaller the difference between the pitch of the grid pattern 3 and the N pitch of the pixels, the longer the period of the phase θ (x, y).

FIG. 5 is a diagram showing a process of generating a phase distribution of moire fringes of the grid pattern 3 when the portion of the structure 4 in which the grid pattern 3 is arranged is displaced by Δx in the x direction. Since the process of generating the phase distribution of the moire fringes in FIGS. 5 (a) to 5 (l) is the same as that in FIGS. 4 (a) to (l), the description thereof will be omitted.

Comparing (b) of FIG. 5 with (b) of FIG. 4, the lattice pattern 3 is displaced by Δx in the x direction due to the displacement of the structure 4. Therefore, the phase θ (x, y) of the moire fringes in FIG. 5 (l) is also different from the phase θ (x, y) of the moire fringes in FIG. 4 (l). Then, the displacement amount Δx of the position of the structure 4 corresponding to the coordinates (x, y) can be calculated from the phase difference Δθ (x, y). In FIG. 5, (m) is an image of the difference between the moire fringe image of FIG. 4 (l) and the moire fringe image of FIG. 5 (l), and the phase difference Δθ (x, y) is. It corresponds to the phase of the image of FIG. 5 (m).

Here, when (b) of FIG. 5 is compared with (b) of FIG. 4, the lattice pattern 3 is slightly deviated, whereas (l) of FIG. 5 is compared with (l) of FIG. The image is greatly deviated, and the phase difference Δθ (x, y) becomes large. That is, the vehicle weight measuring method using the grid pattern 3 has high measurement sensitivity of the displacement of the structure 4.

When the grid pattern 3 is a two-dimensional grid pattern, the image of the grid pattern 3 is smoothed in the x direction to obtain an image of the one-dimensional grid pattern in which the grids are arranged in the y direction. Then, by the same principle as in FIG. 5, the displacement amount Δy in which the portion of the structure 4 in which the lattice pattern 3 is arranged is displaced in the y direction is also calculated.

In the present embodiment, in order for the vehicle weight measuring device 1 to accurately calculate the displacement amount due to the bending of the structure 4 when the vehicle 7 travels on the structure 4, the grid pattern 3 is set in the x direction or the y direction. It is preferable that the vehicle 7 is arranged so as to be perpendicular to the traveling surface of the vehicle 7.

1-3. Vehicle Weight Calculation Method Next, a method of calculating the weight of the vehicle 7 traveling on the structure 4 by WIM will be described.

The vehicle weight measuring device 1 uses the displacement amount of the structure 4 due to the traveling of the vehicle 7, the axle information, and the influence line data indicating the displacement of each point of the structure 4 when the reference vehicle travels on the structure 4. Based on this, the weight of the vehicle 7 is calculated by WIM.

FIG. 6 is a diagram showing an example of influence line data. The horizontal axis of FIG. 6 indicates the length of the structure 4. The vertical axis of FIG. 6 shows the vertical displacement of the structure 4. The waveform shown in FIG. 6 shows the influence line data. The waveform of FIG. 6 shows the displacement of the deflection at an arbitrary point of the structure 4 when a reference vehicle whose weight is known in advance, such as a 1t vehicle, travels on the structure 4, for example, the center of the span of the structure 4. It shows the displacement of the deflection in the part. The influence line data is created in advance before the vehicle weight measuring device 1 starts measuring, and is stored in the storage circuit of the vehicle weight measuring device 1.

FIG. 7 is a diagram illustrating a WIM method and a calculation result based on the influence line data. The horizontal axis of FIG. 7 represents time, and the vertical axis represents the amount of vertical displacement of the structure 4. When the vehicle 7 whose weight is to be calculated travels on the structure 4, the vehicle weight measuring device 1 determines the displacement amount of the portion of the structure 4 in which the grid pattern 3 is arranged, which is suitable for the sampling moire method described above. Calculate in series. The waveform A1 in FIG. 7 represents the time-series data of the displacement amount of the structure 4.

The vehicle weight measuring device 1 arranges the influence line data obtained in advance according to the number of axes of the vehicle 7. For example, when the vehicle 7 is a four-axis vehicle as shown in FIG. 8, the vehicle weight measuring device 1 arranges the four influence line data shown in A21 to A24. When arranging the influence line data, the vehicle weight measuring device 1 uses the approach time and the exit time of each axle of the vehicle 7 with respect to the structure 4, and the length of the horizontal axis of the influence line data shown in FIG. Convert to the time axis.

In the example of FIG. 7, the first axle of the vehicle 7 entered the structure 4 at time ti1 and exited the structure 4 at time to1. Therefore, the influence line data A21 corresponding to the first axis is arranged so that the entry time ti1 and the exit time to1 are the end points. The same applies to the second to fourth axles, and the influence line data A22 to A24 are arranged based on the entry times ti2 to ti4 and the exit times to2 to to4 of each axle.

The influence line data represents the displacement when a vehicle having a predetermined weight, for example, a vehicle of 1 ton as described above, travels. Therefore, when the weight of the j-th axle of the vehicle 7 is Wj for each integer j of 1 to 4, the displacement amount of the structure 4 by the j-th axle is Wj times the influence line data. That is, the displacement amount due to the first axle is represented by A31 obtained by multiplying A21 by W1. Similarly, the displacement amount due to the second axle is A32, which is W2 times A22, the displacement amount due to the third axle is A33, which is W3 times A23, and the displacement amount due to the fourth axle is A33. It is A34 obtained by multiplying A24 by W4.

The displacement amount U by the vehicle 7 is the total of A31 to A34 and is represented by the equation (3).

In the example of FIG. 7, the waveform A4 represents the displacement amount U obtained by the equation (3).

In the present embodiment, the vehicle weight measuring device 1 has a small error between the waveform A4 representing the displacement amount U obtained by using the influence line data and the waveform A1 representing the displacement amount calculated by using the grid pattern 3. As described above, the axle weights W1 to W4 of each axle are calculated. Specifically, the vehicle weight measuring device 1 can calculate W1 to W4 by using a mathematical method such as the least squares method. Then, the vehicle weight measuring device 1 calculates W1 + W2 + W3 + W4, which is the total axle load, as the weight of the vehicle 7.

1-4. Configuration of Vehicle Weight Measuring Device FIG. 9 is a diagram showing a configuration example of the vehicle weight measuring device 1 of the first embodiment. As shown in FIG. 9, the vehicle weight measuring device 1 includes a processing circuit 100, a storage circuit 110, an operation unit 120, and a communication unit 130. The vehicle weight measuring device 1 may be configured such that a part of the components of FIG. 9 is omitted or changed, or another component is added.

The processing circuit 100 executes the vehicle weight measurement program 111 stored in the storage circuit 110, acquires image information captured and generated by the image pickup unit 2, and calculates the weight of the vehicle 7 based on the acquired image information. Perform the processing. In addition, the processing circuit 100 performs various processing according to the operation signal from the operation unit 120, processing for controlling the communication unit 130 for data communication with the external device 8, and the like. The processing circuit 100 is, for example, a CPU (Central Processing Unit) or a DSP (D).
It is realized by igital Signal Processor). The image pickup unit 2 may be included in the vehicle weight measuring device 1.

By executing the vehicle weight measurement program 111, the processing circuit 100 functions as an image information acquisition unit 101, a displacement amount calculation unit 102, an axle information generation unit 103, and a vehicle weight calculation unit 104. That is, the vehicle weight measuring device 1 includes an image information acquisition unit 101, a displacement amount calculation unit 102, an axle information generation unit 103, and a vehicle weight calculation unit 104.

The image information acquisition unit 101 acquires the image information generated by the image pickup unit 2.

The displacement amount calculation unit 102 calculates the displacement amount of the structure 4 based on the image obtained by the imaging unit 2 taking the grid pattern 3 arranged on the structure 4. In the present embodiment, the displacement amount of the structure 4 is calculated by the sampling moire method described above using the image of the grid pattern 3 included in the image information acquired by the image information acquisition unit 101. Specifically, first, the displacement amount calculation unit 102 generates a plurality of moire fringe images with respect to the image of the grid pattern 3. In the present embodiment, the displacement amount calculation unit 102 generates a plurality of thinned-out images different from each other by sampling some pixels and thinning out the other pixels with respect to the lattice pattern 3, and the plurality of thinned-out images are thinned out. The image is interpolated to generate a plurality of moire fringe images. For example, as described with reference to FIGS. 4 and 5, the displacement amount calculation unit 102 generates four moire fringe images having different phases from the image of the grid pattern 3. Next, the displacement amount calculation unit 102 generates a phase distribution of moire fringes by a phase shift method based on a plurality of moire fringe images with respect to the grid pattern 3. For example, as described with reference to FIGS. 4 and 5, the displacement amount calculation unit 102 uses the above equation (2) to determine the phase θ (x,) of the moiré fringes based on the four moiré fringe images for the grid pattern 3. y) is generated. Finally, the displacement amount calculation unit 102 calculates the displacement amount of the structure 4 based on the phase distribution of the moire fringes with respect to the grid pattern 3. Using the table information stored in the displacement amount calculation unit 102, for example, the storage circuit 110 in advance, which defines the correspondence between the phase distribution of the moire fringes with respect to the grid pattern 3 and the displacement amount of the structure 4, the structure 4 is used. The displacement amount of may be calculated.

The axle information generation unit 103 generates axle information including the approach time when each axle of the vehicle 7 enters the structure 4 and the exit time when each axle of the vehicle 7 exits the structure 4. In the present embodiment, the axle information generation unit 103 generates axle information based on an image of the vehicle 7 in which the image pickup unit 2 enters the structure 4 and exits the structure 4. Specifically, the axle information generation unit 103 uses the image of the vehicle 7 entering the structure 4 included in the image information acquired by the image information acquisition unit 101, and each axle of the vehicle 7 enters the structure 4. Find the approach time to do. Further, the axle information generation unit 103 uses the image of the vehicle 7 exiting from the structure 4 included in the image information acquired by the image information acquisition unit 101, and the exit time when each axle of the vehicle 7 exits from the structure 4. Ask for.

In the vehicle weight calculation unit 104, the displacement amount of the structure 4 calculated by the displacement amount calculation unit 102, the axle information generated by the displacement amount calculation unit 102, and the reference vehicle stored in the storage circuit 110 are the structure 4. The weight of the vehicle 7 is calculated based on the influence line data 112 indicating the displacement of each point of the structure 4 when traveling on. In the present embodiment, the vehicle weight calculation unit 104 calculates the weight of the vehicle 7 by the above-mentioned WIM. Specifically, the vehicle weight calculation unit 104 arranges the influence line data 112 for each axle by using the entry time and the exit time of each axle included in the axle information, and the influence line arranged for each axle. Axis of each axle using a mathematical method such as the least squares method so that the error between the amount of displacement obtained using the data 112 and the amount of displacement of the structure 4 calculated by the displacement amount calculation unit 102 becomes small. Calculate the weight. Then, the vehicle weight measuring device 1 calculates the total axle load as the weight of the vehicle 7.

The storage circuit 110 includes a ROM (Read Only Memory) and a RAM (Random Access) (not shown).
Memory). The ROM stores various programs such as the vehicle weight measurement program 111 and predetermined data such as the influence line data 112, and the RAM is used as a work area of the processing circuit 100 and the programs and data read from the ROM. , The data input from the operation unit 120, the data generated by the processing circuit 100, and the like are stored.

The operation unit 120 is an input device composed of operation keys, button switches, and the like, and outputs an operation signal corresponding to the operation by the user to the processing circuit 100.

The communication unit 130 performs various controls for establishing data communication between the processing circuit 100 and the external device 8. For example, the communication unit 130 may transmit the information on the weight of the vehicle 7 calculated by the processing circuit 100 to the external device 8, and the external device 8 may receive the information on the weight of the vehicle 7 and display it on the display unit. ..

In addition, at least a part of the processing circuit 100 may be realized by dedicated hardware. Further, the vehicle weight measuring device 1 may be a single device or may be composed of a plurality of devices.

1-5. Vehicle Weight Measurement Method FIG. 10 is a flowchart showing a procedure of the vehicle weight measurement method of the first embodiment. In addition, in FIG. 10, the order of a plurality of steps may be changed as appropriate.

As shown in FIG. 10, first, in the image information acquisition step S1, the vehicle weight measuring device 1 acquires the image information generated by the image information acquisition unit 101 taken by the image pickup unit 2.

Next, in the vehicle weight measuring device 1, in the displacement amount calculation step S2, the displacement amount calculation unit 102 takes a picture of the grid pattern 3 arranged on the structure 4, and the image pickup unit 2 takes a picture of the structure 4. Calculate the displacement of. Specifically, the displacement amount calculation unit 102 calculates the displacement amount of the structure 4 based on the image of the grid pattern 3 included in the image information acquired in the step S1.

Next, the vehicle weight measuring device 1 is based on an image of the vehicle 7 in which the axle information generation unit 103 enters the structure 4 and exits the structure 4 in the axle information generation step S3. And generate axle information. Specifically, the axle information generation unit 103 uses the image of the vehicle 7 entering the structure 4 included in the image information acquired in step S1, and the approach time when each axle of the vehicle 7 enters the structure 4. Ask for. Further, the axle information generation unit 103 obtains the exit time when each axle of the vehicle 7 exits from the structure 4 by using the image of the vehicle 7 exiting from the structure 4 included in the image information acquired in the step S1.

Next, in the vehicle weight calculation step S4, the vehicle weight measuring device 1 uses the vehicle weight calculation unit 104 in the displacement amount of the structure 4 calculated in the step S2, the axle information generated in the step S3, and the storage circuit 110. The weight of the vehicle 7 is calculated based on the stored influence line data 112 indicating the displacement of each point of the structure 4 when the reference vehicle travels on the structure 4.

The vehicle weight measuring device 1 repeats steps S1 to S4 until the measurement of the weight of the vehicle 7 traveling on the structure 4 is completed (N in step S5).

FIG. 11 is a flowchart showing the procedure of the displacement amount calculation step S2 of FIG. As shown in FIG. 11, first, in step S21, the displacement amount calculation unit 102 generates a plurality of moire fringe images for the image of the grid pattern 3 included in the image information acquired in step S1 of FIG. ..

Next, in step S22, the displacement amount calculation unit 102 generates a phase distribution of moire fringes by a phase shift method based on the plurality of moire fringe images generated in step S21.

Finally, in step S23, the displacement amount calculation unit 102 calculates the displacement amount of the structure 4 based on the phase distribution of the moire fringes generated in step S22.

1-6. Action effect According to the vehicle weight measuring device 1 or the vehicle weight measuring method of the first embodiment described above, the displacement amount of the structure 4 is calculated based on the image of the grid pattern 3 arranged on the structure 4. , The weight of the vehicle 7 can be calculated more accurately from the calculated displacement amount of the structure 4 by using the axle information including the approach time and the exit time of each axle of the vehicle 7 with respect to the structure 4 and the influence line data. can.

In particular, according to the vehicle weight measuring device 1 or the vehicle weight measuring method of the first embodiment, one imaging unit 2 photographs the grid pattern 3 for calculating the displacement amount of the structure 4 and generates the axle information. Since it is also used for photographing the vehicle 7 for the purpose, the cost of the vehicle weight measuring system using the vehicle weight measuring device 1 can be reduced.

2. 2. 2nd Embodiment Hereinafter, regarding the vehicle weight measuring apparatus 1 of the 2nd embodiment, the same components as those of the 1st embodiment are designated by the same reference numerals, and the description overlapping with the 1st embodiment is omitted or simplified. The contents different from the first embodiment will be described.

FIG. 12 is a diagram for explaining an outline of a vehicle weight measuring system using the vehicle weight measuring device 1 of the second embodiment. In the first embodiment, one image pickup unit 2 photographs the vehicle 7 that enters the grid pattern 3 and the structure 4 and exits from the structure 4, but as shown in FIG. 12, in the second embodiment, , The first image pickup unit 2a photographs the grid pattern 3, and the second image pickup unit 2b different from the first image pickup unit 2a photographs the vehicle 7 that enters the structure 4 and exits from the structure 4.

The first image pickup unit 2a has an image pickup element such as a CCD image sensor, and the image pickup element generates an image according to the light incident from the grid pattern 3 or the like arranged in the structure 4. The first image pickup unit 2a may be, for example, a digital camera. The first image pickup unit 2a may be included in the vehicle weight measuring device 1.

When the vehicle 7 travels on the structure 4, the structure 4 bends and is displaced. The vehicle weight measuring device 1 calculates the displacement amount of the structure 4 based on the image obtained by the first imaging unit 2a taking the grid pattern 3. In the second embodiment, the arrangement of the grid pattern 3 and the calculation method of the displacement amount of the structure 4 are the same as those in the first embodiment, and thus the description thereof will be omitted.

The second image pickup unit 2b has an image pickup element such as a CCD image sensor, and the image pickup element generates an image corresponding to the light incident from the vehicle 7 or the like that enters the structure 4 and exits from the structure 4. The second image pickup unit 2b may be, for example, a digital camera. The second image pickup unit 2b may be included in the vehicle weight measuring device 1.

In the vehicle weight measuring device 1, the second imaging unit 2b enters the structure 4, and each axle of the vehicle 7 enters the structure 4 based on an image of the vehicle 7 exiting the structure 4. Generates axle information including the time and the exit time for each axle of the vehicle 7 to exit the structure 4.

Then, the vehicle weight measuring device 1 is based on the calculated displacement amount of the structure 4, the generated axle information, and the influence line data indicating the displacement of each point of the structure 4 when the reference vehicle travels on the structure 4. Then, the weight of the vehicle 7 is calculated by WIM. In the second embodiment, the method for calculating the weight of the vehicle 7 is the same as that in the first embodiment, and thus the description thereof will be omitted.

FIG. 13 is a diagram showing a configuration example of the vehicle weight measuring device 1 of the second embodiment. As shown in FIG. 13, in the vehicle weight measuring device 1 of the second embodiment, the processing circuit 100 is displaced by the image information acquisition unit 101 by executing the vehicle weight measuring program 111 stored in the storage circuit 110. It functions as a quantity calculation unit 102, an axle information generation unit 103, and a vehicle weight calculation unit 104. That is, the vehicle weight measuring device 1 includes an image information acquisition unit 101, a displacement amount calculation unit 102, an axle information generation unit 103, and a vehicle weight calculation unit 104. Since the function of the vehicle weight calculation unit 104 is the same as that of the first embodiment, the description thereof will be omitted.

The image information acquisition unit 101 acquires the first image information generated by the first image pickup unit 2a. In addition, the image information acquisition unit 101 acquires the second image information generated by the second image pickup unit 2b.

The displacement amount calculation unit 102 calculates the displacement amount of the structure 4 based on the image taken by the first imaging unit 2a of the grid pattern 3 arranged on the structure 4. In the present embodiment, the displacement amount of the structure 4 is calculated by the sampling moire method described above using the image of the grid pattern 3 included in the first image information acquired by the image information acquisition unit 101.

The axle information generation unit 103 generates axle information including the approach time when each axle of the vehicle 7 enters the structure 4 and the exit time when each axle of the vehicle 7 exits the structure 4. In the present embodiment, the axle information generation unit 103 generates axle information based on an image of the vehicle 7 in which the second image pickup unit 2b enters the structure 4 and exits the structure 4. Specifically, the axle information generation unit 103 uses the image of the vehicle 7 entering the structure 4 included in the second image information acquired by the image information acquisition unit 101, and each axle of the vehicle 7 is the structure 4. Find the approach time to enter. Further, the axle information generation unit 103 uses the image of the vehicle 7 exiting from the structure 4 included in the second image information acquired by the image information acquisition unit 101, and each axle of the vehicle 7 exits from the structure 4. Find the exit time.

Since the functions of the storage circuit 110, the operation unit 120, and the communication unit 130 are the same as those in the first embodiment, the description thereof will be omitted.

FIG. 14 is a flowchart showing the procedure of the vehicle weight measuring method of the second embodiment. In addition, in FIG. 14, the order of a plurality of steps may be changed as appropriate. As shown in FIG. 14, first, in the vehicle weight measuring device 1, in the first image information acquisition step S101, the image information acquisition unit 101 acquires the first image information photographed and generated by the first image pickup unit 2a. ..

Next, in the vehicle weight measuring device 1, in the second image information acquisition step S102, the image information acquisition unit 101 acquires the second image information photographed and generated by the second image pickup unit 2b.

Next, in the displacement amount calculation step S103, the vehicle weight measuring device 1 has a structure based on an image obtained by the displacement amount calculation unit 102 and the first imaging unit 2a taking a picture of the grid pattern 3 arranged on the structure 4. The displacement amount of the object 4 is calculated. Specifically, the displacement amount calculation unit 102 calculates the displacement amount of the structure 4 based on the image of the grid pattern 3 included in the first image information acquired in the step S101. The detailed procedure of the displacement amount calculation step S103 is as shown in FIG.

Next, in the vehicle weight measuring device 1, in the axle information generation step S104, the axle information generation unit 103 captures an image of the vehicle 7 in which the second imaging unit 2b enters the structure 4 and exits the structure 4. Generates axle information based on. Specifically, the axle information generation unit 103 uses the image of the vehicle 7 entering the structure 4 included in the second image information acquired in the step S102, and each axle of the vehicle 7 enters the structure 4. Find the approach time. Further, the axle information generation unit 103 uses the image of the vehicle 7 exiting from the structure 4 included in the second image information acquired in the step S102 to set the exit time at which each axle of the vehicle 7 exits from the structure 4. Ask.

Next, in the vehicle weight calculation process S105, the vehicle weight measuring device 1 is used in the vehicle weight calculation unit 104, the displacement amount of the structure 4 calculated in the process S103, the axle information generated in the process S104, and the storage circuit 110. The weight of the vehicle 7 is calculated based on the stored influence line data 112 indicating the displacement of each point of the structure 4 when the reference vehicle travels on the structure 4.

The vehicle weight measuring device 1 repeats steps S101 to S105 until the measurement of the weight of the vehicle 7 traveling on the structure 4 is completed (N in step S106).

According to the vehicle weight measuring device 1 or the vehicle weight measuring method of the second embodiment described above, the displacement amount of the structure 4 is calculated based on the image of the grid pattern 3 arranged on the structure 4, and the vehicle The weight of the vehicle 7 can be calculated more accurately from the calculated displacement amount of the structure 4 by using the axle information including the approach time and the exit time of each axle of 7 with respect to the structure 4 and the influence line data.

In particular, according to the vehicle weight measuring device 1 or the vehicle weight measuring method of the second embodiment, the first imaging unit 2a for photographing the grid pattern 3 may photograph the vehicle 7 entering and exiting the structure 4. Even in an environment where it is not possible, the weight of the vehicle 7 can be calculated by the second imaging unit 2b taking a picture of the vehicle 7 entering and exiting the structure 4. Alternatively, according to the vehicle weight measuring device 1 or the vehicle weight measuring method of the second embodiment, since it is not necessary for the first imaging unit 2a to photograph the vehicle 7, the grid pattern 3 is photographed with a high resolution to obtain the vehicle 7. The weight of the car can be calculated with high accuracy.

3. 3. 3rd Embodiment Hereinafter, regarding the vehicle weight measuring device 1 of the 3rd embodiment, the same components as those of the 1st embodiment or the 2nd embodiment are designated by the same reference numerals, and the same as those of the 1st embodiment or the 2nd embodiment. The duplicated description will be omitted or simplified, and the contents different from those of the first embodiment and the second embodiment will be mainly described.

FIG. 15 is a diagram for explaining an outline of a vehicle weight measuring system using the vehicle weight measuring device 1 of the third embodiment. In the second embodiment, the first imaging unit 2a photographs the grid pattern 3, and the first imaging unit 2a photographs the vehicle 7 in which the second imaging unit 2b enters the structure 4 and exits the structure 4. However, as shown in FIG. 15, in the third embodiment, the first image pickup unit 2a photographs the grid pattern 3, and the second image pickup unit 2b different from the first image pickup unit 2a enters the structure 4. 7 is photographed, and the vehicle 7 in which the third image pickup unit 2c different from the first image pickup unit 2a and the second image pickup unit 2b exits from the structure 4 is photographed.

When the vehicle 7 travels on the structure 4, the structure 4 bends and is displaced. The vehicle weight measuring device 1 calculates the displacement amount of the structure 4 based on the image obtained by the first imaging unit 2a taking the grid pattern 3. In the third embodiment, the arrangement of the grid pattern 3 and the calculation method of the displacement amount of the structure 4 are the same as those in the first embodiment, and thus the description thereof will be omitted.

The second image pickup unit 2b has an image pickup element such as a CCD image sensor, and the image pickup element generates an image according to the light incident from the vehicle 7 or the like entering the structure 4. The second image pickup unit 2b may be, for example, a digital camera. The second image pickup unit 2b may be included in the vehicle weight measuring device 1.

The third image pickup unit 2c has an image pickup element such as a CCD image sensor, and the image pickup element generates an image corresponding to the light incident from the vehicle 7 or the like exiting from the structure 4. The third image pickup unit 2c may be, for example, a digital camera. The third imaging unit 2c may be included in the vehicle weight measuring device 1.

The vehicle weight measuring device 1 is based on an image of a vehicle 7 in which the second image pickup unit 2b enters the structure 4 and an image of a vehicle 7 in which the third image pickup unit 2c exits the structure 4. , Generates axle information including the approach time when each axle of the vehicle 7 enters the structure 4 and the exit time when each axle of the vehicle 7 exits the structure 4. Specifically, the vehicle weight measuring device 1 obtains the approach time at which each axle of the vehicle 7 enters the structure 4 based on an image obtained by photographing the vehicle 7 in which the second imaging unit 2b enters the structure 4. Based on the image of the vehicle 7 exiting from the structure 4 by the third imaging unit 2c, the exit time at which each axle of the vehicle 7 exits from the structure 4 is obtained.

Then, the vehicle weight measuring device 1 is based on the calculated displacement amount of the structure 4, the generated axle information, and the influence line data indicating the displacement of each point of the structure 4 when the reference vehicle travels on the structure 4. Then, the weight of the vehicle 7 is calculated by WIM. In the third embodiment, the method for calculating the weight of the vehicle 7 is the same as that in the first embodiment, and thus the description thereof will be omitted.

FIG. 16 is a diagram showing a configuration example of the vehicle weight measuring device 1 of the third embodiment. As shown in FIG. 16, in the vehicle weight measuring device 1 of the third embodiment, the processing circuit 100 is displaced by the image information acquisition unit 101 by executing the vehicle weight measuring program 111 stored in the storage circuit 110. It functions as a quantity calculation unit 102, an axle information generation unit 103, and a vehicle weight calculation unit 104. That is, the vehicle weight measuring device 1 includes an image information acquisition unit 101, a displacement amount calculation unit 102, an axle information generation unit 103, and a vehicle weight calculation unit 104. Since the function of the displacement amount calculation unit 102 is the same as that of the second embodiment, the description thereof will be omitted. Since the function of the vehicle weight calculation unit 104 is the same as that of the first embodiment, the description thereof will be omitted.

The image information acquisition unit 101 acquires the first image information generated by the first image pickup unit 2a. In addition, the image information acquisition unit 101 acquires the second image information generated by the second image pickup unit 2b. Further, the image information acquisition unit 101 acquires the third image information generated by the third image pickup unit 2c.

The axle information generation unit 103 generates axle information including the approach time when each axle of the vehicle 7 enters the structure 4 and the exit time when each axle of the vehicle 7 exits the structure 4. In the present embodiment, the axle information generation unit 103 captures an image of the vehicle 7 in which the second image pickup unit 2b enters the structure 4 and an image of the vehicle 7 in which the third image pickup unit 2c exits the structure 4. And, based on, the axle information is generated. Specifically, the axle information generation unit 103 uses the image of the vehicle 7 entering the structure 4 included in the second image information acquired by the image information acquisition unit 101, and each axle of the vehicle 7 is the structure 4. Find the approach time to enter. Further, the axle information generation unit 103 uses the image of the vehicle 7 exiting from the structure 4 included in the third image information acquired by the image information acquisition unit 101, and each axle of the vehicle 7 exits from the structure 4. Find the exit time.

Since the functions of the storage circuit 110, the operation unit 120, and the communication unit 130 are the same as those in the first embodiment, the description thereof will be omitted.

FIG. 17 is a flowchart showing the procedure of the vehicle weight measuring method of the third embodiment. In addition, in FIG. 17, the order of a plurality of steps may be changed as appropriate. As shown in FIG. 17, first, in the vehicle weight measuring device 1, in the first image information acquisition step S201, the image information acquisition unit 101 acquires the first image information photographed and generated by the first image pickup unit 2a. ..

Next, in the vehicle weight measuring device 1, in the second image information acquisition step S202, the image information acquisition unit 101 acquires the second image information photographed and generated by the second image pickup unit 2b.

Next, in the vehicle weight measuring device 1, in the third image information acquisition step S203, the image information acquisition unit 101 acquires the third image information photographed and generated by the third image pickup unit 2c.

Next, in the displacement amount calculation step S204, the vehicle weight measuring device 1 has a structure based on an image obtained by the displacement amount calculation unit 102 and the first imaging unit 2a taking a picture of the grid pattern 3 arranged on the structure 4. The displacement amount of the object 4 is calculated. Specifically, the displacement amount calculation unit 102 calculates the displacement amount of the structure 4 based on the image of the grid pattern 3 included in the first image information acquired in the step S201. The detailed procedure of the displacement amount calculation step S204 is as shown in FIG.

Next, in the vehicle weight measuring device 1, in the axle information generation step S205, the axle information generation unit 103 captures an image of the vehicle 7 in which the second imaging unit 2b enters the structure 4 and exits the structure 4. Generates axle information based on. Specifically, the axle information generation unit 103 uses the image of the vehicle 7 entering the structure 4 included in the second image information acquired in the step S202, and each axle of the vehicle 7 enters the structure 4. Find the approach time. Further, the axle information generation unit 103 uses the image of the vehicle 7 exiting from the structure 4 included in the third image information acquired in the step S203 to set the exit time at which each axle of the vehicle 7 exits from the structure 4. Ask.

Next, in the vehicle weight calculation step S206, the vehicle weight measuring device 1 uses the vehicle weight calculation unit 104 in the displacement amount of the structure 4 calculated in the process S204, the axle information generated in the process S205, and the storage circuit 110. The weight of the vehicle 7 is calculated based on the stored influence line data 112 indicating the displacement of each point of the structure 4 when the reference vehicle travels on the structure 4.

The vehicle weight measuring device 1 repeats steps S201 to S206 until the measurement of the weight of the vehicle 7 traveling on the structure 4 is completed (N in step S207).

According to the vehicle weight measuring device 1 or the vehicle weight measuring method of the third embodiment described above, the displacement amount of the structure 4 is calculated based on the image of the grid pattern 3 arranged on the structure 4, and the vehicle The weight of the vehicle 7 can be calculated more accurately from the calculated displacement amount of the structure 4 by using the axle information including the approach time and the exit time of each axle of 7 with respect to the structure 4 and the influence line data.

In particular, according to the vehicle weight measuring device 1 or the vehicle weight measuring method of the third embodiment, the first imaging unit 2a for photographing the grid pattern 3 may photograph the vehicle 7 entering and exiting the structure 4. Even in an environment where it is not possible, the weight of the vehicle 7 can be measured by the second imaging unit 2b photographing the vehicle 7 entering the structure 4 and the third imaging unit 2c photographing the vehicle 7 exiting the structure 4. Can be calculated. Alternatively, according to the vehicle weight measuring device 1 or the vehicle weight measuring method of the third embodiment, since it is not necessary for the first imaging unit 2a to photograph the vehicle 7, the grid pattern 3 is photographed with a high resolution to obtain the vehicle 7. The weight of the car can be calculated with high accuracy.

4. Fourth Embodiment Hereinafter, regarding the vehicle weight measuring apparatus 1 of the fourth embodiment, the same components as those of the first embodiment are designated by the same reference numerals, and the description overlapping with the first embodiment is omitted or simplified. The contents different from the first embodiment will be described.

FIG. 18 is a diagram for explaining an outline of a vehicle weight measuring system using the vehicle weight measuring device 1 of the fourth embodiment. In the first embodiment, the image pickup unit 2 photographs the vehicle 7 that enters the lattice pattern 3 and the structure 4 and exits from the structure 4, but as shown in FIG. 18, in the fourth embodiment, the image pickup is performed. Part 2 photographs the grid pattern 3, the first acceleration sensor 5a detects the acceleration generated by the vehicle 7 entering the structure 4, and the second acceleration sensor 5b detects the acceleration generated by the vehicle 7 leaving the structure 4. do.

When the vehicle 7 travels on the structure 4, the structure 4 bends and is displaced. The vehicle weight measuring device 1 calculates the displacement amount of the structure 4 based on the image obtained by the imaging unit 2 taking the grid pattern 3. In the fourth embodiment, the arrangement of the grid pattern 3 and the calculation method of the displacement amount of the structure 4 are the same as those in the first embodiment, and thus the description thereof will be omitted.

The first acceleration sensor 5a is provided at the first end of the structure 4 into which the vehicle 7 enters, and detects the acceleration generated by the vehicle 7 entering the structure 4. The first acceleration sensor 5a may be, for example, a MEMS acceleration sensor using a MEMS (Micro Electro Mechanical Systems) oscillator, or a crystal acceleration sensor using a crystal oscillator.

The second acceleration sensor 5b is provided at the second end of the structure 4 where the vehicle 7 exits, and detects the acceleration generated by the vehicle 7 exiting the structure 4. The second acceleration sensor 5b may be, for example, a MEMS acceleration sensor or a crystal acceleration sensor.

The vehicle weight measuring device 1 has an approach time at which each axle of the vehicle 7 enters the structure 4 and each of the vehicles 7 based on the output signal of the first acceleration sensor 5a and the output signal of the second acceleration sensor 5b. Generates axle information including the exit time when the axle exits the structure 4. Specifically, the vehicle weight measuring device 1 obtains the approach time when each axle of the vehicle 7 enters the structure 4 based on the output signal of the first acceleration sensor 5a, and uses the output signal of the second acceleration sensor 5b as the approach time. Based on this, the exit time at which each axle of the vehicle 7 exits from the structure 4 is obtained.

Then, the vehicle weight measuring device 1 is based on the calculated displacement amount of the structure 4, the generated axle information, and the influence line data indicating the displacement of each point of the structure 4 when the reference vehicle travels on the structure 4. Then, the weight of the vehicle 7 is calculated by WIM. In the fourth embodiment, the method for calculating the weight of the vehicle 7 is the same as that in the first embodiment, and thus the description thereof will be omitted.

Next, a method of generating axle information by the vehicle weight measuring device 1 of the fourth embodiment will be described with reference to FIGS. 19 to 22. FIG. 19 shows the acceleration on the approach side of the vehicle 7 detected by the first acceleration sensor 5a and the exit of the vehicle 7 detected by the second acceleration sensor 5b when the four-axis vehicle 7 travels on the bridge which is the structure 4. It is a figure which shows an example of the acceleration of a side.

The vehicle weight measuring device 1 calculates the acceleration intensity when each axle enters the structure 4 based on the output signal of the first acceleration sensor 5a, and each axle has a structure based on the output signal of the second acceleration sensor 5b. Calculate the acceleration intensity when exiting from the object 4. FIG. 20 is a diagram in which the acceleration amplitude at each time in FIG. 19 is converted into an acceleration intensity. In the example of FIG. 20, the acceleration intensity is increased when each axle of the vehicle 7 enters or exits the structure 4.

Then, the vehicle weight measuring device 1 sets the time when the acceleration intensity calculated based on the output signal of the first acceleration sensor 5a exceeds a predetermined threshold value, and the approach time when each axle enters the structure 4 in order from the leading axle. Get as. Further, the vehicle weight measuring device 1 sets the time when the acceleration intensity calculated based on the output signal of the second acceleration sensor 5b exceeds a predetermined threshold value, and the exit time when each axle exits the structure 4 in order from the first axle. Get as. FIG. 21 is a diagram in which the acceleration intensity of FIG. 20 is binarized at a predetermined threshold value. In the example of FIG. 21, the entry time and exit time for each structure 4 of the four axles are acquired.

Further, the vehicle weight measuring device 1 compares the approach time pattern and the exit time pattern of each axle, determines whether or not the two patterns are due to the same vehicle 7, and is based on the same vehicle 7. If it is determined to be, the axle information including the entry time and the exit time of each axle of the vehicle 7 is generated. Since the distance between the axles does not change when the vehicle 7 travels, if the speed at which the vehicle 7 travels on the structure 4 is constant, the pattern of the approach time and the pattern of the exit time will match. For example, the vehicle weight measuring device 1 slides one of the two patterns so as to match the entry time and the exit time of the first axle, and the difference between the entry time and the exit time of each of the second and subsequent axles. If all of the two patterns are equal to or less than a predetermined threshold value, it is determined that the two patterns are due to the same vehicle 7, and if not, it is determined that the two patterns are not due to the same vehicle 7. FIG. 22 is a diagram in which the pattern of the exit time is slid so as to match the entry time and the exit time of the leading axle with respect to FIG. 21. Note that FIG. 22 is enlarged in the horizontal axis direction with respect to FIG. 21. In the example of FIG. 22, the pattern of the entry time of the four axles into the structure 4 and the pattern of the exit time of the four axles from the structure 4 are substantially the same, and the two patterns are the same vehicle 7. It is determined that this is due to.

FIG. 23 is a diagram showing a configuration example of the vehicle weight measuring device 1 of the fourth embodiment. As shown in FIG. 23, in the vehicle weight measuring device 1 of the fourth embodiment, the processing circuit 100 displaces the image information acquisition unit 101 by executing the vehicle weight measuring program 111 stored in the storage circuit 110. It functions as a quantity calculation unit 102, an axle information generation unit 103, a vehicle weight calculation unit 104, and a sensor signal acquisition unit 105. That is, the vehicle weight measuring device 1 includes an image information acquisition unit 101, a displacement amount calculation unit 102, an axle information generation unit 103, a vehicle weight calculation unit 104, and a sensor signal acquisition unit 105. Since the functions of the image information acquisition unit 101, the displacement amount calculation unit 102, and the vehicle weight calculation unit 104 are the same as those in the first embodiment, the description thereof will be omitted.

The sensor signal acquisition unit 105 acquires the output signal of the first acceleration sensor 5a and the output signal of the second acceleration sensor 5b.

The axle information generation unit 103 generates axle information including the approach time when each axle of the vehicle 7 enters the structure 4 and the exit time when each axle of the vehicle 7 exits the structure 4. In the present embodiment, the axle information generation unit 103 generates axle information based on the output signal of the first acceleration sensor 5a and the output signal of the second acceleration sensor 5b. Specifically, the axle information generation unit 103 obtains the approach time at which each axle of the vehicle 7 enters the structure 4 based on the output signal of the first acceleration sensor 5a acquired by the sensor signal acquisition unit 105. Further, the axle information generation unit 103 obtains the exit time when each axle of the vehicle 7 exits from the structure 4 based on the output signal of the second acceleration sensor 5b acquired by the sensor signal acquisition unit 105.

Since the functions of the storage circuit 110, the operation unit 120, and the communication unit 130 are the same as those in the first embodiment, the description thereof will be omitted.

FIG. 24 is a flowchart showing the procedure of the vehicle weight measuring method of the fourth embodiment. In addition, in FIG. 24, the order of a plurality of steps may be changed as appropriate. As shown in FIG. 24, first, in the image information acquisition step S301, the vehicle weight measuring device 1 acquires the image information generated by the image information acquisition unit 101 taken by the image pickup unit 2.

Next, in the vehicle weight measuring device 1, in the sensor signal acquisition step S302, the sensor signal acquisition unit 105 acquires the output signal of the first acceleration sensor 5a and the output signal of the second acceleration sensor 5b.

Next, in the vehicle weight measuring device 1, in the displacement amount calculation step S303, the displacement amount calculation unit 102 takes a picture of the grid pattern 3 arranged on the structure 4, and the image pickup unit 2 takes a picture of the structure 4. Calculate the displacement of. Specifically, the displacement amount calculation unit 102 calculates the displacement amount of the structure 4 based on the image of the grid pattern 3 included in the image information acquired in the step S301. The detailed procedure of the displacement amount calculation step S303 is as shown in FIG.

Next, in the axle information generation step S304, the vehicle weight measuring device 1 has the axle information generation unit 103 based on the output signal of the first acceleration sensor 5a and the output signal of the second acceleration sensor 5b. To generate. Specifically, the axle information generation unit 103 obtains the approach time at which each axle of the vehicle 7 enters the structure 4 based on the output signal of the first acceleration sensor 5a acquired in the step S302. Further, the axle information generation unit 103 obtains the exit time when each axle of the vehicle 7 exits from the structure 4 based on the output signal of the second acceleration sensor 5b acquired in the step S302.

Next, in the vehicle weight calculation process S305, the vehicle weight measuring device 1 tells the vehicle weight calculation unit 104 the displacement amount of the structure 4 calculated in the process S303, the axle information generated in the process S304, and the storage circuit 110. The weight of the vehicle 7 is calculated based on the stored influence line data 112 indicating the displacement of each point of the structure 4 when the reference vehicle travels on the structure 4.

The vehicle weight measuring device 1 repeats steps S301 to S305 until the measurement of the weight of the vehicle 7 traveling on the structure 4 is completed (N in step S306).

According to the vehicle weight measuring device 1 or the vehicle weight measuring method of the fourth embodiment described above, the displacement amount of the structure 4 is calculated based on the image of the grid pattern 3 arranged on the structure 4, and the vehicle The weight of the vehicle 7 can be calculated more accurately from the calculated displacement amount of the structure 4 by using the axle information including the approach time and the exit time of each axle of 7 with respect to the structure 4 and the influence line data.

In particular, according to the vehicle weight measuring device 1 or the vehicle weight measuring method of the fourth embodiment, an environment in which the imaging unit 2 that captures the grid pattern 3 cannot photograph the vehicle 7 that enters or exits the structure 4. Even so, the first acceleration sensor 5a detects the acceleration generated by the vehicle 7 entering the structure 4, and the second acceleration sensor 5b detects the acceleration generated by the vehicle 7 exiting the structure 4. The weight of 7 can be calculated. Alternatively, according to the vehicle weight measuring device 1 or the vehicle weight measuring method of the fourth embodiment, since the imaging unit 2 does not need to photograph the vehicle 7, the grid pattern 3 is photographed at a high resolution to obtain the weight of the vehicle 7. Can be calculated with high accuracy.

5. Fifth Embodiment Hereinafter, regarding the vehicle weight measuring device 1 of the fifth embodiment, the same components as those of the first embodiment are designated by the same reference numerals, and the description overlapping with the first embodiment is omitted or simplified. The contents different from the first embodiment will be described.

FIG. 25 is a diagram for explaining an outline of a vehicle weight measuring system using the vehicle weight measuring device 1 of the fifth embodiment. In the first embodiment, the image pickup unit 2 photographs the vehicle 7 that enters the lattice pattern 3 and the structure 4 and exits from the structure 4, but as shown in FIG. 25, in the fifth embodiment, the image pickup is performed. Part 2 photographs the lattice pattern 3, the first strain gauge 6a detects the strain caused by the vehicle 7 entering the structure 4, and the second strain gauge 6b detects the strain caused by the vehicle 7 leaving the structure 4. do.

When the vehicle 7 travels on the structure 4, the structure 4 bends and is displaced. The vehicle weight measuring device 1 calculates the displacement amount of the structure 4 based on the image obtained by the imaging unit 2 taking the grid pattern 3. In the fifth embodiment, the arrangement of the grid pattern 3 and the calculation method of the displacement amount of the structure 4 are the same as those in the first embodiment, and thus the description thereof will be omitted.

The first strain gauge 6a is provided at the first end of the structure 4 into which the vehicle 7 enters, and the resistance value changes according to the strain generated by the vehicle 7 entering the structure 4.

The second strain gauge 6b is provided at the second end of the structure 4 from which the vehicle 7 exits, and the resistance value changes according to the strain generated by the vehicle 7 exiting from the structure 4.

The vehicle weight measuring device 1 has an approach time at which each axle of the vehicle 7 enters the structure 4 and the vehicle 7 based on the signal obtained by the first strain gauge 6a and the signal obtained by the second strain gauge 6b. Generates axle information including the exit time when each axle of the above exits the structure 4. Specifically, the vehicle weight measuring device 1 has an approach time at which each axle of the vehicle 7 enters the structure 4 based on the first strain information such as the voltage value converted from the resistance value of the first strain gauge 6a. Is obtained, and the exit time at which each axle of the vehicle 7 exits from the structure 4 is determined based on the second strain information such as the voltage value converted from the resistance value of the second strain gauge 6b.

Then, the vehicle weight measuring device 1 is based on the calculated displacement amount of the structure 4, the generated axle information, and the influence line data indicating the displacement of each point of the structure 4 when the reference vehicle travels on the structure 4. Then, the weight of the vehicle 7 is calculated by WIM. In the fourth embodiment, the method of calculating the weight of the vehicle 7 is the same as that of the first embodiment, and thus the description thereof will be omitted.

FIG. 26 is a diagram showing a configuration example of the vehicle weight measuring device 1 of the fifth embodiment. As shown in FIG. 26, in the vehicle weight measuring device 1 of the fifth embodiment, the processing circuit 100 displaces the image information acquisition unit 101 by executing the vehicle weight measuring program 111 stored in the storage circuit 110. It functions as a quantity calculation unit 102, an axle information generation unit 103, a vehicle weight calculation unit 104, and a strain information acquisition unit 106. That is, the vehicle weight measuring device 1 includes an image information acquisition unit 101, a displacement amount calculation unit 102, an axle information generation unit 103, a vehicle weight calculation unit 104, and a strain information acquisition unit 106. Since the functions of the image information acquisition unit 101, the displacement amount calculation unit 102, and the vehicle weight calculation unit 104 are the same as those in the first embodiment, the description thereof will be omitted.

The strain information acquisition unit 106 acquires first strain information such as a signal obtained from the first strain gauge 6a, for example, a voltage value converted from the resistance value of the first strain gauge 6a. Further, the strain information acquisition unit 106 acquires a signal obtained from the second strain gauge 6b, for example, a second strain information such as a voltage value converted from the resistance value of the second strain gauge 6b.

The axle information generation unit 103 generates axle information including the approach time when each axle of the vehicle 7 enters the structure 4 and the exit time when each axle of the vehicle 7 exits the structure 4. In the present embodiment, the axle information generation unit 103 generates axle information based on the signal obtained from the first strain gauge 6a and the signal obtained from the second strain gauge 6b. Specifically, the axle information generation unit 103 obtains the approach time at which each axle of the vehicle 7 enters the structure 4 based on the first strain information acquired by the strain information acquisition unit 106. Further, the axle information generation unit 103 obtains the exit time when each axle of the vehicle 7 exits from the structure 4 based on the second strain information acquired by the strain information acquisition unit 106.

Since the functions of the storage circuit 110, the operation unit 120, and the communication unit 130 are the same as those in the first embodiment, the description thereof will be omitted.

FIG. 27 is a flowchart showing the procedure of the vehicle weight measuring method of the fifth embodiment. In addition, in FIG. 27, the order of a plurality of steps may be changed as appropriate. As shown in FIG. 27, first, in the image information acquisition step S401, the vehicle weight measuring device 1 acquires the image information generated by the image information acquisition unit 101 taken by the image pickup unit 2.

Next, in the vehicle weight measuring device 1, in the strain information acquisition step S402, the strain information acquisition unit 106 obtains the first strain information, which is a signal obtained from the first strain gauge 6a, and the signal obtained from the second strain gauge 6b. The second strain information is acquired.

Next, in the vehicle weight measuring device 1, in the displacement amount calculation step S403, the displacement amount calculation unit 102 takes a picture of the grid pattern 3 arranged on the structure 4, and the image pickup unit 2 takes a picture of the structure 4. Calculate the displacement of. Specifically, the displacement amount calculation unit 102 calculates the displacement amount of the structure 4 based on the image of the grid pattern 3 included in the image information acquired in the step S401. The detailed procedure of the displacement amount calculation step S403 is as shown in FIG.

Next, in the axle information generation step S404, the vehicle weight measuring device 1 is based on the signal obtained by the axle information generation unit 103 by the first strain gauge 6a and the signal obtained by the second strain gauge 6b. Generate axle information. Specifically, the axle information generation unit 103 obtains the approach time at which each axle of the vehicle 7 enters the structure 4 based on the first strain information acquired in the step S402. Further, the axle information generation unit 103 obtains the exit time when each axle of the vehicle 7 exits from the structure 4 based on the second strain information acquired in the step S402.

Next, in the vehicle weight calculation step S405, the vehicle weight measuring device 1 uses the vehicle weight calculation unit 104 in the displacement amount of the structure 4 calculated in the process S403, the axle information generated in the process S404, and the storage circuit 110. The weight of the vehicle 7 is calculated based on the stored influence line data 112 indicating the displacement of each point of the structure 4 when the reference vehicle travels on the structure 4.

The vehicle weight measuring device 1 repeats steps S401 to S405 until the measurement of the weight of the vehicle 7 traveling on the structure 4 is completed (N in step S406).

According to the vehicle weight measuring device 1 or the vehicle weight measuring method of the fifth embodiment described above, the displacement amount of the structure 4 is calculated based on the image of the grid pattern 3 arranged in the structure 4, and the vehicle The weight of the vehicle 7 can be calculated more accurately from the calculated displacement amount of the structure 4 by using the axle information including the approach time and the exit time of each axle of 7 with respect to the structure 4 and the influence line data.

In particular, according to the vehicle weight measuring device 1 or the vehicle weight measuring method of the fifth embodiment, an environment in which the imaging unit 2 that captures the grid pattern 3 cannot photograph the vehicle 7 that enters or exits the structure 4. Even so, by detecting the strain caused by the vehicle 7 entering the structure 4 by the first strain gauge 6a and detecting the strain caused by the vehicle 7 leaving the structure 4 by the second strain gauge 6b, the vehicle. The weight of 7 can be calculated. Alternatively, according to the vehicle weight measuring device 1 or the vehicle weight measuring method of the fifth embodiment, since the imaging unit 2 does not need to photograph the vehicle 7, the grid pattern 3 is photographed with a high resolution to obtain the weight of the vehicle 7. Can be calculated with high accuracy.

6. Modifications The present invention is not limited to the present embodiment, and various modifications can be carried out within the scope of the gist of the present invention.

For example, in each of the above embodiments, a road bridge is taken as an example of a bridge as a structure 4, but the bridge may be a railway bridge. Further, in each of the above embodiments, the bridge is taken as an example of the structure 4, but the structure 4 may be deformed by the movement of the vehicle.

The above-described embodiments and modifications are merely examples, and the present invention is not limited thereto. For example, it is also possible to appropriately combine each embodiment and each modification.

The present invention includes substantially the same configurations as those described in the embodiments (eg, configurations with the same function, method and result, or configurations with the same purpose and effect). The present invention also includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. Further, the present invention includes a configuration having the same action and effect as the configuration described in the embodiment or a configuration capable of achieving the same object. Further, the present invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

The following contents are derived from the above-described embodiments and modifications.

One aspect of the vehicle weight measuring device is
A displacement amount calculation unit that calculates the displacement amount of the structure based on an image obtained by capturing a grid pattern provided on the structure by the imaging unit.
An axle information generation unit that generates axle information including an approach time in which each axle of a vehicle enters the structure and an exit time in which each axle of the vehicle exits the structure.
The weight of the vehicle is calculated based on the calculated displacement amount of the structure, the generated axle information, and the influence line data indicating the displacement of each point of the structure when the reference vehicle travels on the structure. Vehicle weight calculation unit and
including.

According to this vehicle weight measuring device, from the displacement amount of the structure calculated based on the image of the grid pattern using the axle information including the entry time and the exit time for the structure of each axle of the vehicle and the influence line data. The weight of the vehicle can be calculated more accurately.

In one aspect of the vehicle weight measuring device,
The axle information generation unit is
The image pickup unit may generate the axle information based on an image of the vehicle entering the structure and exiting the structure.

According to this vehicle weight measuring device, one imaging unit is also used for photographing the grid pattern for calculating the displacement amount of the structure and photographing the vehicle for generating the axle information, so that the vehicle weight measuring system The cost can be reduced.

In one aspect of the vehicle weight measuring device,
The imaging unit is used as the first imaging unit.
The axle information generation unit is
A second imaging unit different from the first imaging unit may generate the axle information based on an image of the vehicle entering and exiting the structure.

According to this vehicle weight measuring device, even in an environment where the first image pickup unit that captures the grid pattern cannot photograph the vehicle entering and exiting the structure, the second image pickup unit captures the structure. The weight of the vehicle can be calculated by photographing the vehicle entering and exiting. Alternatively, according to this vehicle weight measuring device, since it is not necessary for the first imaging unit to photograph the vehicle, the weight of the vehicle can be calculated with high accuracy by photographing the grid pattern with high resolution.

In one aspect of the vehicle weight measuring device,
The imaging unit is used as the first imaging unit.
The axle information generation unit is
An image of the vehicle in which a second image pickup unit different from the first image pickup unit enters the structure and a third image pickup unit different from the first image pickup unit and the second image pickup unit are taken from the structure. The axle information may be generated based on an image of the vehicle leaving the vehicle.

According to this vehicle weight measuring device, the second imaging unit enters the structure even in an environment where the first imaging unit that captures the grid pattern cannot photograph the vehicle entering and exiting the structure. The weight of the vehicle can be calculated by taking a picture of the vehicle to be used and the third imaging unit taking a picture of the vehicle leaving the structure. Alternatively, according to this vehicle weight measuring device, since it is not necessary for the first imaging unit to photograph the vehicle, the weight of the vehicle can be calculated with high accuracy by photographing the grid pattern with high resolution.

In one aspect of the vehicle weight measuring device,
The axle information generation unit is
The output signal of the first accelerometer provided at the first end of the structure into which the vehicle enters and the output signal of the second accelerometer provided at the second end of the structure from which the vehicle exits. And, the axle information may be generated based on.

According to this vehicle weight measuring device, the first acceleration sensor enters the structure even in an environment where the image pickup unit that captures the lattice pattern cannot photograph the vehicle entering or leaving the structure. The weight of the vehicle can be calculated by detecting the acceleration generated by the vehicle and the second acceleration sensor detecting the acceleration generated by the vehicle exiting the structure. Alternatively, according to this vehicle weight measuring device, since the image pickup unit does not need to photograph the vehicle, the weight of the vehicle can be calculated with high accuracy by photographing the grid pattern with high resolution.

In one aspect of the vehicle weight measuring device,
The axle information generation unit is
Obtained by a signal obtained by a first strain gauge provided at the first end of the structure into which the vehicle enters and by a second strain gauge provided at the second end of the structure from which the vehicle exits. The axle information may be generated based on the signal to be generated.

According to this vehicle weight measuring device, a vehicle that enters the structure by the first strain gauge even in an environment where the image pickup unit that captures the lattice pattern cannot photograph the vehicle that enters or exits the structure. The weight of the vehicle can be calculated by detecting the strain caused by the strain and detecting the strain caused by the vehicle exiting the structure by the second strain gauge. Alternatively, according to this vehicle weight measuring device, since the image pickup unit does not need to photograph the vehicle, the weight of the vehicle can be calculated with high accuracy by photographing the grid pattern with high resolution.

One aspect of the vehicle weight measurement method is
The imaging unit calculates the displacement amount of the structure based on the image obtained by capturing the grid pattern provided on the structure.
Axle information including the approach time when each axle of the vehicle enters the structure and the exit time when each axle of the vehicle exits the structure is generated.
The weight of the vehicle is calculated based on the calculated displacement amount of the structure, the generated axle information, and the influence line data indicating the displacement of each point of the structure when the reference vehicle travels on the structure. do.

According to this vehicle weight measurement method, from the amount of displacement of the structure calculated based on the image of the grid pattern using the axle information including the entry time and the exit time for the structure of each axle of the vehicle and the influence line data. The weight of the vehicle can be calculated more accurately.

1 ... Vehicle weight measuring device, 2 ... Imaging unit, 3 ... Lattice pattern, 4 ... Structure, 5a ... First acceleration sensor, 5b ... Second acceleration sensor, 6a ... First strain gauge, 6b ... Second strain gauge, 7 ... Vehicle, 8 ... External device, 100 ... Processing circuit, 101 ... Image information acquisition unit, 102 ... Displacement amount calculation unit, 103 ... Axle information generation unit, 104 ... Vehicle weight calculation unit, 105 ... Sensor signal acquisition unit, 106 ... Strain information acquisition unit, 110 ... Storage circuit, 111 ... Vehicle weight measurement program, 112 ... Influence line data, 120 ... Operation unit, 130 ... Communication unit

Claims (7)

A displacement amount calculation unit that calculates the displacement amount of the structure based on an image obtained by capturing a grid pattern provided on the structure by the imaging unit.
An axle information generation unit that generates axle information including an approach time in which each axle of a vehicle enters the structure and an exit time in which each axle of the vehicle exits the structure.
The weight of the vehicle is calculated based on the calculated displacement amount of the structure, the generated axle information, and the influence line data indicating the displacement of each point of the structure when the reference vehicle travels on the structure. Vehicle weight calculation unit and
Including vehicle weight measuring device. In claim 1,
The axle information generation unit is
A vehicle weight measuring device in which the image pickup unit generates axle information based on an image of a vehicle that enters the structure and exits the structure. In claim 1,
The imaging unit is used as the first imaging unit.
The axle information generation unit is
A vehicle weight measuring device in which a second imaging unit different from the first imaging unit generates axle information based on an image of the vehicle entering and exiting the structure. In claim 1,
The imaging unit is used as the first imaging unit.
The axle information generation unit is
An image of the vehicle in which a second image pickup unit different from the first image pickup unit enters the structure and a third image pickup unit different from the first image pickup unit and the second image pickup unit are taken from the structure. A vehicle weight measuring device that generates the axle information based on an image of the vehicle leaving the vehicle. In claim 1,
The axle information generation unit is
The output signal of the first accelerometer provided at the first end of the structure into which the vehicle enters and the output signal of the second accelerometer provided at the second end of the structure from which the vehicle exits. A vehicle weight measuring device that generates the axle information based on the above. In claim 1,
The axle information generation unit is
Obtained by a signal obtained by a first strain gauge provided at the first end of the structure into which the vehicle enters and by a second strain gauge provided at the second end of the structure from which the vehicle exits. A vehicle weight measuring device that generates the axle information based on the signal to be generated. The imaging unit calculates the displacement amount of the structure based on the image obtained by capturing the grid pattern provided on the structure.
Axle information including the approach time when each axle of the vehicle enters the structure and the exit time when each axle of the vehicle exits the structure is generated.
The weight of the vehicle is calculated based on the calculated displacement amount of the structure, the generated axle information, and the influence line data indicating the displacement of each point of the structure when the reference vehicle travels on the structure. How to measure the vehicle weight.

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