Control system for snow-melting device

Abstract

To provide a control system for a snow-melting device capable of determining the presence or absence of snow cover with a simple mechanism by using an imaging device such as a camera for photographing a road surface.SOLUTION: A control system 10 for controlling a snow-melting device 50 installed on a road surface 90 comprises a camera 30 arranged to photograph a symbol unit 80 including fixed information drawn on the road surface 90, and a control unit 20 for acquiring an image photographed by the camera 30 and recognizing the information included in the symbol unit 80 from the image; the control unit 20 outputs a control signal to the snow-melting device 50 based on whether or not the information included in the symbol unit 80 in the image is recognized.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a control system for controlling a snow melting device that melts snow that has accumulated on a road surface. [Background technology]

[0002] In snowy regions, snow melting equipment is installed to continuously remove snow from roads during the winter to ensure safe passage for pedestrians and vehicles. By installing snow melting equipment on road surfaces, snow removal can be automated where necessary. However, snow melting equipment requires running costs such as electricity and fuel costs. For this reason, efforts are being made to reduce running costs by automating the control of the snow melting equipment's power management.

[0003] Known control systems for snow melting devices indirectly determine the presence or absence of snow by, for example, detecting road surface temperature or air temperature, or sensing snowfall in the atmosphere. If these methods determine that there is snow on the road surface, the control system turns on the snow melting device, and if they determine that there is no snow on the road surface, the control system turns off the snow melting device. However, control systems that use the above methods to determine the presence or absence of snow can result in false positives.

[0004] For this reason, in order to improve the accuracy of snow accumulation determination, a system is known in which a camera is installed to photograph the road surface and the presence or absence of snow is directly determined based on the images acquired by the camera. For example, a system in which a person monitors the images taken by the camera and remotely controls the power supply of a snow melting device depending on the presence or absence of snow is conceivable, but the need for manned monitoring makes this system expensive and difficult to implement, especially in small facilities.

[0005] There is also a known system that analyzes images captured by a camera using a trained model generated by machine learning, deep learning, etc. to determine whether or not snow has accumulated. Such a control system is disclosed, for example, in Patent Document 1. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 7246056 Summary of the Invention [Problem to be solved by the invention]

[0007] To create a trained model, it is necessary to prepare a large number of images with different road surface characteristics and conditions, as well as the presence or absence of snow. Road surface characteristics involve many factors, such as the color and material of the road, unevenness, and whether or not there is slope. Furthermore, road surface conditions can vary not only depending on whether there is snow, but also on whether or not there is sunshine and whether or not there is rain. For this reason, it is not easy to create a trained model that can accurately determine whether or not there is snow.

[0008] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a control system for a snow melting device that can determine the presence or absence of snow using a simple mechanism using an imaging device such as a camera that photographs the road surface. [Means for solving the problem]

[0009] In order to solve the above problem, the control system for a snow melting device of the present invention is a control system for controlling a snow melting device installed on a road surface, and is equipped with an imaging device positioned so as to be able to photograph a symbol portion containing certain information painted on the road surface, and a control unit that acquires an image photographed by the imaging device and recognizes the information contained in the symbol portion from the image, and the control unit outputs a control signal to the snow melting device based on whether or not the information contained in the symbol portion in the image can be recognized.

[0010] In the snow melting device control system according to the present invention, the symbol portion may be a barcode or a two-dimensional code containing the information.

[0011] In the snow melting device control system according to the present invention, the information included in the symbol portion may also include error correction information.

[0012] In addition, in the control system for a snow melting device according to the present invention, the snow melting device and the control system may each be connected to a communication network, and the control unit may output the control signal to the snow melting device via the communication network.

[0013] In addition, the control system for the snow melting device of the present invention may be equipped with a temperature sensor that detects the surface temperature of the road surface, and the control unit may be configured to modify the control signal according to the surface temperature of the road surface detected by the temperature sensor.

[0014] In addition, the control system for a snow melting device of the present invention may be configured so that the imaging device is positioned so as to be able to photograph each of the multiple symbol portions painted at multiple locations on the road surface, and the control unit may output a control signal to the snow melting device based on whether or not each of the information contained in the multiple symbol portions in the image can be recognized. [Effects of the Invention]

[0015] The snow melting device control system of the present invention can determine the presence or absence of snow using a simple mechanism that uses an imaging device to photograph the road surface and controls the snow melting device, which allows the snow melting device to operate only as needed when snow accumulates, thereby reducing running costs. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a perspective view showing the arrangement of a camera that constitutes the control system of this embodiment, a road surface having a symbol portion, and a snow melting device. [Figure 2] 1 is a block diagram showing the configuration of a control system and a snow melting device according to an embodiment of the present invention; [Figure 3] The diagrams show the symbol and a cross section of the road surface at the symbol location photographed by a camera. (a) shows the road surface with no snow, (b) shows the road surface with snow that lightly covers the symbol, and (c) shows the road surface with a thick layer of snow. [Figure 4]10(a) to 10(d) are plan views of the symbol portion according to the modified examples. [Figure 5] FIG. 10 is a block diagram showing the configuration of a control system and a snow melting device according to a modified example. [Figure 6] FIG. 10 is a perspective view showing the arrangement of a camera, a road surface having a symbol portion, and a snow melting device that constitute a control system according to a second modified example. DETAILED DESCRIPTION OF THE INVENTION

[0017] An embodiment of the present invention will be described in detail with reference to the drawings. A control system 10 of this embodiment transmits control signals to a snow melting device 50 that can melt snow on a road surface 90, and controls the operation of the snow melting device 50, including turning it on and off.

[0018] As shown in Fig. 1, a snow melting device 50 is installed on a road surface 90. The snow melting device 50 melts snow on the road surface 90 by heating, thereby exposing the snow-covered road surface 90. There are no limitations on the heating method of the snow melting device 50, but it may be, for example, an electric heating wire buried under the road surface 90, or piping for circulating hot water heated by a boiler or the like buried under the road surface. The snow melting device 50 is capable of melting snow within a certain range of the road surface 90.

[0019] A symbol portion 80 is drawn on the road surface 90. The symbol portion 80 can be drawn on the road surface 90 using road marking paint. However, the symbol portion 80 may be drawn by other means as long as a certain degree of durability on the road surface 90 is ensured. The symbol portion 80 is made up of figures, characters, etc. containing certain information. The symbol portion 80 in FIG. 1 is a two-dimensional code and contains character string information.

[0020] A support pole 32 is erected near the road surface 90, and a camera 30 is fixed to the upper end of the support pole 32 as an imaging device. The camera 30 is positioned so that it can capture an image of the area of ​​the road surface 90 including the symbol unit 80 from above. The symbol unit 80 can be positioned at any position on the road surface 90 that can be captured by the camera 30. When there is snow on the road surface 90, the control content of the control system 10 differs depending on the snow accumulation condition at the symbol unit 80, so it is preferable that the symbol unit 80 be positioned in a position where vehicles and pedestrians cannot enter.

[0021] 2, the control system 10 has a control unit 20, a camera 30, and a transmission unit 22. The camera 30 captures an image of the road surface 90 including the symbol portion 80 as described above. The control unit 20 acquires the image captured by the camera 30 and recognizes the information included in the symbol portion 80 from the acquired image. The transmission unit 22 transmits a control signal from the control unit 20 to the snow melting device 50.

[0022] The snow melting device 50 and the control system 10 are each connected to a communication network 60. The transmitter 22 can transmit a control signal to the snow melting device 50 via the communication network 60. The control system 10 is connected to the communication network 60 wirelessly. This allows for a reduction in the amount of wiring required when installing the control system 10. The snow melting device 50 may also be connected to the communication network 60 wirelessly. Note that the control system 10 and the snow melting device 50 may each be connected to the communication network 60 via a wire.

[0023] The control unit 20 acquires images from the camera 30 at regular intervals and determines whether or not the information contained in the symbol portion 80 in the image can be recognized. Whether or not the information can be recognized can be determined by whether or not the character string contained in the symbol portion 80, which is a two-dimensional code, can be decoded. The control unit 20 can be configured with a computer including a CPU, memory, storage device, etc.

[0024] As shown in FIG. 3(a), the symbol portion 80 drawn on the road surface 90 is exposed upward when there is no snow, and therefore the symbol portion 80 is clearly captured in the image captured by the camera 30. Therefore, the control unit 20 can decode the character string from the symbol portion 80 and recognize the contained information. As shown in FIG. 3(b), as snow 100 begins to accumulate on the road surface 90, the symbol portion 80 begins to be covered with the snow 100. Accordingly, the symbol portion 80 captured by the camera 30 gradually becomes blurred. Because the two-dimensional code that forms the symbol portion 80 contains error correction information, even if the image becomes blurred, the control unit 20 can still decode the character string and recognize the information to a certain extent. As shown in FIG. 3(c), as more snow 100 accumulates on the road surface 90, the symbol portion 80 is completely covered with the snow 100. In this case, the symbol portion 80 captured by the camera 30 becomes indistinguishable, and the character string cannot be decoded, so the control unit 20 cannot recognize the information. In reality, the control unit 20 changes from being able to recognize the information in the symbol section 80 to being unable to recognize it between the states of Figure 3(b) and Figure 3(c). The strength of the error correction information in the symbol section 80 can be set. If the strength of the error correction information is high, the character string can be decoded from the symbol section 80 even if it becomes more unclear. By adjusting the strength of the error correction information in the symbol section 80, the sensitivity of whether or not the information in the symbol section 80 can be recognized relative to the amount of snowfall can be adjusted.

[0025] The control unit 20 outputs a control signal to the snow melting device 50 based on whether or not the information contained in the symbol section 80 can be recognized in the image captured by the camera 30. The control unit 20 can output a control signal each time an image is acquired from the camera 30 at regular intervals. In this case, if the control unit 20 can recognize the information contained in the symbol section 80, it outputs a control signal to turn the snow melting device 50 off. If the control unit 20 cannot recognize the information contained in the symbol section 80, it outputs a control signal to turn the snow melting device 50 on.

[0026] The control unit 20 may output a control signal only if there is a change in whether or not information can be recognized between the previous image acquisition and the current image acquisition. As shown in Table 1 below, the control unit 20 can output a control signal to turn on the snow melting device 50 if it was able to recognize information from the symbol unit 80 when the previous image was acquired but was unable to recognize information from the symbol unit 80 when the current image was acquired, and can output a control signal to turn off the snow melting device 50 if it was unable to recognize information from the symbol unit 80 when the previous image was acquired but was able to recognize information from the symbol unit 80 when the current image was acquired. The control unit 20 does not output a control signal if it was unable to recognize information from the symbol unit 80 when the previous image was acquired or the current image was acquired, or if it was able to recognize information from the symbol unit 80 when the previous image was acquired or the current image was acquired.

[0027] [Table 1]

[0028] The control unit 20 may refer to the information recognition status when the previous two images were acquired, and output a control signal only if the information recognition status has changed and the information recognition status has changed twice consecutively. As shown in Table 2 below, if the control unit 20 was able to recognize information from the symbol unit 80 when the image before last was acquired, but was unable to recognize information from the symbol unit 80 when the previous image was acquired, and if the information is not recognized from the symbol unit 80 when the current image is acquired, the control unit 20 outputs a control signal to turn on the snow melting device 50 because the information recognition status has changed from the image before last to the image before last and there have been two consecutive changes in the information recognition status. If the control unit 20 was unable to recognize information from the symbol unit 80 when the image before last was acquired, but was able to recognize information from the symbol unit 80 when the previous image was acquired, and if the information is recognized from the symbol unit 80 when the current image is acquired, the control unit 20 outputs a control signal to turn off the snow melting device 50. If there is no change in whether or not the information can be recognized between the time before last and the previous time, or if there was a change in whether or not the information could be recognized between the time before last and the previous time but there is a change again between the previous time and the current time, the control unit 20 does not output a control signal. By referencing the past two times whether or not the information can be recognized in this way, it is possible to prevent the snow melting device 50 from being repeatedly turned on and off, such as at the beginning of snow accumulation or just before the completion of snow melting. It is also possible to prevent false detection when there is a temporary change in whether or not the information can be recognized due to factors other than snow accumulation.

[0029] [Table 2]

[0030] When the snow melting device 50 is in the off state and receives a control signal to turn it on from the control unit 20, it switches to the on state. When the snow melting device 50 is in the on state and receives a control signal to turn it on from the control unit 20, or when the snow melting device 50 is in the off state and receives a control signal to turn it off from the control unit 20, it maintains that state. When the snow melting device 50 is in the on state and receives a control signal to turn it off from the control unit 20, it switches to the off state.

[0031] In this way, the control unit 20 outputs a control signal for the snow melting device 50 based on whether the control unit 20 can recognize the information contained in the symbol unit 80 captured by the camera 30. Therefore, the control system 10 of this embodiment can determine the presence or absence of snow using a simple mechanism using the camera 30 capturing an image of the road surface 90 and control the snow melting device 50. This allows the snow melting device 50 to operate only as needed when snow accumulates, thereby reducing running costs. Furthermore, because the symbol unit 80 is a two-dimensional code containing error correction information, the snow melting device 50 can be turned on only after a certain amount of snow has accumulated. Therefore, the snow melting device 50 can be prevented from operating when there is only a small amount of snow that would melt naturally, further reducing the running costs of the snow melting device 50.

[0032] The symbol portion is not limited to a two-dimensional code, and can be any figure or character containing some information. As shown in FIG. 4(a), the symbol portion 83 may be a barcode. Since a barcode contains certain information, like a two-dimensional code, the control unit 20 can output a control signal to the snow melting device 50 based on whether or not the information contained in the symbol portion 83 in the image captured by the camera 30 can be recognized.

[0033] As shown in FIG. 4(b), the symbol section 84 may be characters. Because characters contain certain information, the control unit 20 can determine whether the information contained in the symbol section 84 can be recognized by character recognition. The characters may be numbers, or other types of characters such as hiragana, katakana, kanji, or the alphabet. The number of characters can also be set arbitrarily.

[0034] As shown in Fig. 4(c), the symbol portion 85 may be a geometric figure. In the case of the figure in Fig. 4(c), since the figure contains the information of triple concentric circles, the control unit 20 can determine whether or not the information contained in the symbol portion 85 can be recognized by image pattern recognition. The figure of the symbol portion 85 can be set arbitrarily, and may also be a combination of multiple figures.

[0035] As shown in Fig. 4(d), the symbol section 86 may be a picture. In the case of the picture in Fig. 4(d), since the picture contains information such as a picture of a car, the control unit 20 can determine whether or not the information contained in the symbol section 86 can be recognized by image pattern recognition. The picture in the symbol section 86 can be set arbitrarily, and may also be a combination of multiple pictures, figures, or characters, an AR marker, or the like.

[0036] A modified example of the control system will now be described. As shown in Fig. 5, in the control system 12, a temperature sensor 24 may be connected to the control unit 20 in addition to the camera 30. The temperature sensor 24 can measure the surface temperature of the area of ​​the road surface 90 photographed by the camera 30. The temperature sensor 24 can be an infrared camera or the like that can measure the surface temperature from a remote position. However, the temperature sensor 24 is not limited to this, and may also be a thermometer or the like that is installed on the road surface 90.

[0037] The control unit 20 can acquire the surface temperature of the road surface 90 from the temperature sensor 24 at any timing. When the control unit 20 acquires an image captured by the camera 30 and determines whether the information contained in the symbol unit 80 can be recognized, the control unit 20 can modify the control signal in accordance with the surface temperature of the road surface 90 acquired from the temperature sensor 24. For example, when the control unit 20 outputs a control signal to turn on the snow melting device 50 based on whether the information contained in the symbol unit 80 can be recognized, if the surface temperature of the road surface 90 is above a certain level, the control unit 20 can determine that snow accumulation has been erroneously detected and not output the control signal. The control unit 20 can also output a control signal to change the heating intensity of the snow melting device 50 in addition to turning it on and off. In this case, the control unit 20 can output a control signal to increase the heating intensity of the snow melting device 50 when the surface temperature of the road surface 90 acquired from the temperature sensor 24 is low, and output a control signal to decrease the heating intensity of the snow melting device 50 when the surface temperature of the road surface 90 is high. The control unit 20 may also make other modifications to the control signal in accordance with the surface temperature of the road surface 90 acquired from the temperature sensor 24.

[0038] In the control system 12, the control unit 20 and the snow melting device 50 are directly connected without going through a communication network. The connection between the control unit 20 and the snow melting device 50 may be wireless or wired. In this way, the control system 12 and the snow melting device 50 may be configured as a stand-alone type.

[0039] The snow melting device 50 may be configured to be able to heat multiple regions of the road surface 90. As shown in Fig. 6, the snow melting device 50 can heat either or both of a first region 55 and a second region 56 of the road surface 90. On the road surface 90, a symbol portion 80 is drawn in the first region 55, and a second symbol portion 81 is drawn in the second region 56. The camera 30 is disposed on the support 32 so as to be able to capture images of both the symbol portion 80 and the second symbol portion 81.

[0040] The control unit 20 outputs a control signal to the snow melting device 50 based on whether the information contained in the symbol unit 80 and the second symbol unit 81 in the image acquired from the camera 30 can be recognized. For the symbol unit 80 located in the first region 55 of the road surface 90, the control unit 20 outputs a control signal to turn off the snow melting device 50 if the information can be recognized from the image, and outputs a control signal to turn on the snow melting device 50 if the information cannot be recognized from the image. For the second symbol unit 81 located in the second region 56 of the road surface 90, the control unit 20 outputs a control signal to turn off the snow melting device 50 if the information can be recognized from the image, and outputs a control signal to turn on the snow melting device 50 if the information cannot be recognized from the image. This allows the snow accumulation to be determined for each region of the road surface 90 and the snow melting device 50 to be controlled. Even if the snow melting device 50 does not switch on and off for each region of the road surface 90, control such as adjusting the heating intensity may be performed based on whether multiple symbol units 80, 81 can be recognized.

[0041] Although the embodiments of the present invention have been described above, the application of the present invention is not limited to these embodiments and can be applied in various ways within the scope of its technical concept. In the above-described embodiments, the control unit 20 determines the presence or absence of snow based on whether or not it can recognize the information contained in the symbol portion 80 from the image acquired from the camera 30. However, a trained model created by machine learning or the like may also be used in conjunction with the image analysis to more accurately determine the presence or absence of snow. In the above-described embodiments, the imaging device is the camera 30, but any imaging device capable of recognizing the symbol portion 80 may be used, and the imaging device may be a two-dimensional code reader, a barcode reader, or the like. [Explanation of symbols]

[0042] 10. Control System 12 Control System 20 Control Unit 22 Transmitter 24 Temperature Sensor 30 Camera 32 Pillar 50 Snow melting equipment 60 Communication Network 80 Symbols 81 Second Symbol 90 Road surface

Claims

1. A control system for controlling a snow melting device installed on a road surface, an imaging device arranged to be able to photograph a symbol portion containing certain information painted on the road surface; a control unit that acquires an image captured by the imaging device and recognizes the information included in the symbol unit from the image, The control unit outputs a control signal to the snow melting device based on whether the information contained in the symbol portion in the image can be recognized.

2. The snow melting device control system according to claim 1 , wherein the symbol portion is a barcode or a two-dimensional code containing the information.

3. 3. The snow melting device control system according to claim 1, wherein the information included in the symbol portion includes error correction information.

4. The snow melting device and the control system are each connected to a communication network, 3. The control system for a snow melting device according to claim 1, wherein the control unit outputs the control signal to the snow melting device via the communication network.

5. a temperature sensor for detecting the surface temperature of the road surface; 3. The control system for a snow melting device according to claim 1, wherein the control unit modifies the control signal in accordance with the surface temperature of the road surface detected by the temperature sensor.

6. the imaging device is disposed so as to be able to capture images of the plurality of symbol portions painted at a plurality of locations on the road surface, The control system for a snow melting device according to claim 1 or 2, wherein the control unit outputs a control signal to the snow melting device based on whether each of the pieces of information included in the plurality of symbol portions in the image can be recognized.

Images