JP2020180437A - Road surface evaluation system, road surface evaluation method, and road surface evaluation program - Google Patents

Abstract

To provide a road surface evaluation system that can grasp how a road surface changes over the passage of time.SOLUTION: A road surface evaluation system comprises: a storage unit that stores imaging data acquired from an imaging unit in association with position data; and a data processing unit that reads the imaging data and the position data from the storage unit. The data processing unit includes: a parameter calculation unit that calculates a travel vector indicating a travel direction of an inspection vehicle at the time when the imaging data is captured from an amount of change in the position data at prescribed time intervals; and a data retrieval unit that refers to the position data associated with the plurality of imaging data stored in the storage unit and the travel vector, determines a similarity of each, and reads comparison source imaging data and comparison destination imaging data in which the road surface of the same location is imaged from the storage unit.SELECTED DRAWING: Figure 1

Description

The present invention relates to a road surface evaluation system, a road surface evaluation method, and a road surface evaluation program.

Conventionally, there is known a road surface evaluation system that images the condition of the road surface on which a vehicle travels, detects dents, steps, cracks, etc. generated on the road surface, and evaluates (determines) the road surface condition based on the degree thereof.
As such a road surface evaluation system, Patent Document 1 below discloses a configuration in which vibration during traveling of a vehicle is detected by an acceleration sensor to determine the state of the road surface.

Japanese Unexamined Patent Publication No. 2013-79889

However, although such a road surface evaluation system can evaluate the condition of the road surface at the time of inspection, it has not been possible to grasp how the road surface changes over time in the regular inspection. ..

Therefore, an object of the present invention is to provide a road surface evaluation system capable of grasping how the road surface changes over time with the passage of time.

In order to solve the above problems, the road surface evaluation system of the present invention is mounted on an inspection vehicle traveling on the road surface to be inspected, and the inspection vehicle obtains imaging data acquired from an imaging unit that images the state of the road surface around the vehicle. The data processing unit includes a storage unit that stores the position data indicating the position of the image in association with the position data acquired from the positioning system, and a data processing unit that reads the imaging data and the position data from the storage unit. It was associated with a parameter calculation unit that calculates a progress vector indicating the traveling direction of the inspection vehicle at the time when the imaging data was imaged from the amount of change in the data at predetermined time intervals, and a plurality of imaging data stored in the storage unit. It is provided with a data search unit that refers to the position data and the progress vector, determines the similarity between them, and reads the comparison source imaging data and the comparison destination imaging data in which the road surface at the same location is imaged from the storage unit. Road surface evaluation system.

Further, the parameter calculation unit sets a position threshold in which a range of a predetermined position is added to the position data associated with the comparison source imaging data, and an angle in which a range of a predetermined angle is added to the traveling vector. A threshold is set, and the data search unit uses the imaging data having the position data within the position threshold and the progress vector within the angle threshold as the comparison destination imaging data having high similarity to the comparison source imaging data. It may be read from the storage unit.

Further, the imaging unit may be arranged at the center in the left-right direction in front of the inspection vehicle so as to face the front of the inspection vehicle.

Further, the data processing unit includes a data correction unit that corrects the imaging data read by the data search unit, and the data correction unit sets a three-dimensional virtual area in the imaging data and of each vertex that partitions the three-dimensional virtual area. By using the coordinates to calculate the viewpoint information indicating the position of the viewpoint of the imaging data, and using the viewpoint information, the comparison destination imaging data is geometrically corrected so as to be the viewpoint of the comparison source imaging data. The comparison destination correction imaging data to be compared with the comparison source imaging data may be generated.

Further, in the road surface evaluation method of the present invention, the computer mounts on the inspection vehicle traveling on the road surface to be inspected, and obtains the imaging data acquired from the imaging unit that images the state of the road surface around the vehicle. A storage step of associating the position data indicating the position with the position data acquired from the positioning system and storing the position data in the storage unit, and a data processing step of reading the imaging data and the position data from the storage unit are executed. The data processing step includes a parameter calculation step of calculating a progress vector indicating the traveling direction of the inspection vehicle at the time when the imaging data is captured from the amount of change of the position data at predetermined time, and a parameter calculation step in the storage unit. The comparison source imaging data and the comparison destination imaging data in which the road surface at the same location is imaged by referring to the stored position data associated with the plurality of imaging data and the traveling vector to determine the similarity between them. It includes a data search step to be read from the storage unit.

Further, in the road surface evaluation program of the present invention, the image data obtained from the imaging unit which is mounted on the inspection vehicle traveling on the inspection target road surface and images the state of the road surface around the vehicle is obtained by the inspection vehicle. A storage function for storing the position data indicating the position in the storage unit in association with the position data acquired from the positioning system for specifying the position, and a data processing function for reading the imaging data and the position data from the storage unit are realized. The data processing function includes a parameter calculation function that calculates a progress vector indicating the traveling direction of the inspection vehicle at the time when the imaging data is captured from the amount of change of the position data at predetermined time, and a storage unit. The comparison source imaging data and the comparison destination imaging data in which the road surface at the same location is imaged by referring to the stored position data associated with the plurality of imaging data and the traveling vector to determine the similarity between them. It has a data search function to read from the storage unit.

In the road surface evaluation system of the present invention, the data search unit refers to the position data associated with the imaging data and the progress vector of the inspection vehicle, and compares a plurality of imaging data stored in the storage unit. As a result, the data search unit can read the comparison source imaging data and the comparison destination imaging data in which the road surface at the same location is imaged from the storage unit. Therefore, by confirming and comparing the comparison source imaging data and the comparison destination imaging data, for example, when the comparison destination imaging data is taken after the comparison source imaging data, the time passes. It is possible to grasp how the road surface changes over time.

It is a figure explaining the outline of the road surface evaluation system of this invention. It is a block diagram which shows the structure of the road surface evaluation system shown in FIG. It is a figure explaining the image pickup range by the image pickup part shown in FIG. It is a figure which shows the structure of the attribute data including the position data. It is a figure which shows an example of the display content by the display part shown in FIG. It is a figure which shows another example of the display content by the display part shown in FIG. (A) It is a figure explaining the elevation-depression angle of an image pickup part, and (b) it is a figure explaining a three-dimensional virtual area. It is a figure explaining the calibration of the imaging part. It is a flow chart which shows the process which the data search unit reads the data stored in the storage unit. It is a flow chart which shows the process which the data correction part performs geometric correction.

(System configuration)
The road surface evaluation system 1 according to the embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the road surface evaluation system 1 according to the present embodiment images the state of a portion of the road surface on which the inspection vehicle 100 travels, which is located in front of the inspection vehicle 100, and has dents, steps, and the like formed on the road surface. It is a system that detects cracks and evaluates (determines) the road surface condition based on the degree of cracks.
FIG. 1 is a diagram illustrating an outline of the road surface evaluation system 1 of the present invention.

The road surface evaluation system 1 travels while capturing the state of the road surface in front of the inspection vehicle 100 with the action camera 10, and acquires the position information of the action camera 10 that changes from moment to moment by the positioning system 12. The acquired imaging data and position information are input to the operation terminal 20 via various storage media such as a communication means or a flash memory. Thereby, the state of the road surface to be inspected set on the map can be confirmed by displaying it on the operation terminal 20.

The operation terminal 20 is a personal computer provided with a display device (display unit 26) and an input device (keyboard, etc.). The operation terminal 20 is not limited to a fixed terminal, and may be a mobile terminal such as a smartphone or a tablet.

Inside the operation terminal 20, a plurality of imaging data are stored in the storage unit 21. Of these imaging data, the data search unit 23 searches for the comparison source imaging data and the comparison destination imaging data.
Then, the data correction unit 25 performs geometric correction on the comparison destination imaging data to make it easy to compare the comparison source imaging data and the comparison destination imaging data, and displays the data on the display unit 26. Each of these processes will be described in detail separately.

The communication means is a technical means for connecting the road surface evaluation system 1 and the operation terminal 20 to each other, and although it is a wireless communication means in the illustrated example, it may be a wired communication means.
Specifically, the communication means are wireless LAN (wireless LAN: WLAN), wide area network (wide area network: WAN), ISDNs (integrated service digital networks), wireless LANs, LTE (long term evolution), LTE (long term evolution). 4th generation (4G), 5th generation (5G), CDMA (code division network access), WCDMA (registered trademark), Ethernet (registered trademark) and the like.

Further, the communication means is not limited to these examples, for example, the public switched telephone network (Public Switched Telephone Network: PSTN), Bluetooth (registered trademark), Bluetooth Low Energy, optical line, ADSL. (Asymmetric Digital Subscriber Line) A line, a satellite communication network, or the like may be used, and any communication means may be used.

Further, the communication means may be, for example, NB-IoT (Narrow Band IoT) or eMTC (enhanced Machine Type Communication). NB-IoT and eMTC are wireless communication methods for IoT, and are communication means capable of long-distance communication at low cost and low power consumption.

Moreover, the communication means may be a combination of these. Further, the communication means may include a plurality of different communication means in which these examples are combined.
For example, the communication means may include a wireless network by LTE and a wired network such as an intranet which is a closed network.

Next, the configuration of the road surface evaluation system 1 will be described with reference to FIG. FIG. 2 is a block diagram showing the configuration of the road surface evaluation system 1.
As shown in FIG. 2, the road surface evaluation system 1 includes an action camera 10 and an operation terminal 20. The action camera 10 includes an imaging unit 11, a positioning system 12, and a transmitting unit 13.

The action camera 10 is mounted on the inspection vehicle 100, and the image pickup unit 11 captures the state of the road surface around the vehicle. The action camera 100 refers to a camera provided with a positioning system 12 and capable of detecting a change in position when moving while taking an image.
The action camera 10 is arranged at the center in the left-right direction in front of the inspection vehicle 100 so as to face the front of the inspection vehicle 100.

The elevation / depression angle of the imaging unit 11 is an angle at which a predetermined point in front of the imaging unit 11 is located at the center of the imaging range in the vertical direction.
Specifically, in front of the imaging unit 11, the imaging unit 11 has a predetermined horizontal distance between a point to be imaged in the central portion in the vertical direction of the imaging range and directly below the imaging unit 11. The elevation and depression angles are set.

It is customary to carry out road inspections within an inspection range of 10 m, and in this embodiment, half of that, 5 m, is set as the inspection range. In order to photograph the road surface in this inspection range without excess or deficiency, 5 m was set as a predetermined distance. The size of the predetermined distance can be changed arbitrarily.
In the present embodiment, as described above, the predetermined distance is 5 m. In this case, as shown in FIG. 3, a point 5 m from the imaging unit 11 is located at the center of the imaging range in the vertical direction. Here, FIG. 3 is a diagram for explaining an imaging range by the imaging unit 11 shown in FIG.

As shown in FIG. 2, the positioning system 12 acquires position data indicating the position of the action camera 10. A GPS system can be adopted as the positioning system 12.
The position data acquired by the positioning system 12 includes at least longitude information and latitude information. The position data may include altitude information.

The transmission unit 13 is an interface that transmits the image pickup data acquired by the image pickup unit 11 and the position information acquired by the positioning system 12 to the operation terminal 20 using the network described above.

The operation terminal 20 includes a storage unit 21, a data processing unit 22, a display unit 26, and a receiving unit 27.
The storage unit 21 has a function of storing various control programs required for the road surface evaluation system 1 to operate. The storage unit 21 is realized by various storage media such as HDD, SSD, and flash memory.

By executing the control program stored in the storage unit 21, the data processing unit 22 realizes each function to be realized as the road surface evaluation system 1. Each function referred to here includes a storage function, a display function, a parameter calculation function, a data search function, and a data correction function as functions realized by the data processing unit 22.

The storage unit 21 stores the imaging data acquired by the imaging unit 11 in association with the position data. The storage unit 21 stores attribute data including position data for each frame of the imaging data. The structure of the attribute data will be described with reference to FIG. FIG. 4 is a diagram showing attribute data including position data.

As shown in FIG. 4, in the attribute data, position information, moving distance, traveling speed, and traveling vector are stored in association with the shooting time indicating the frame number of the imaging data.
The shooting time refers to the time when each frame constituting the moving image is imaged. In this embodiment, 60 frames are imaged per second. Therefore, the shooting time is every 0.16 seconds. The number of frames per second can be changed arbitrarily.

The position information is latitude information and longitude information acquired by the positioning system 12. In the attribute data, the position information for each shooting time is stored in accordance with the change in the position of the vehicle that changes from moment to moment.
The moving distance refers to the moving distance from the shooting start point at the corresponding shooting time, and is a value calculated based on the position information.

The traveling speed indicates the traveling speed of the inspection vehicle 100 at the corresponding shooting time. The traveling speed is a value calculated by the shooting time and the moving distance.
The travel vector indicates the traveling direction of the inspection vehicle 100 at the corresponding shooting time. The progress vector is the position information at the reference shooting time (for example, ss.032) and the shooting time (ss.096) after a predetermined time (for example, 0.64 seconds) from this shooting time (for example, ss.032). It is obtained by comparing with the position information. The predetermined time does not have to be 0.64 seconds and can be set arbitrarily.

The display unit 26 is a monitor device that displays the imaging data and the position data stored in the storage unit 21. The contents displayed on the display unit 26 will be described with reference to FIGS. 5 and 6.
FIG. 5 is a diagram showing an example of display contents by the display unit 26 shown in FIG. FIG. 6 is a diagram showing another example of the display content displayed by the display unit 26 shown in FIG.

As shown in FIG. 5, a moving image display unit 26A for reproducing captured data is provided on the left side of the display unit 26. A reference line is displayed on the moving image display unit 26A as a reference for the distance from the imaging unit 11. The distance from the image pickup unit 11 to the reference line can be arbitrarily changed.
The imaged data can be arbitrarily operated by the inspector to perform forward or reverse feed, or to select the imaged data at a predetermined imaging time.

A map display unit 26B is provided on the right side of the moving image display unit 26A. On the map display unit 26B, a map showing the position where the imaging data displayed on the moving image display unit 26A is captured is displayed. The position of the inspection vehicle 100 acquired by the positioning system 12 is indicated by an icon on the map.
The icon indicating the position of the inspection vehicle 100 moves on the map as the imaging data displayed on the moving image display unit 26A advances. The latitude and longitude, which are the position information at this time, are displayed on the lower side of the map display unit 26B.

As shown in FIG. 6, when a damaged part of the road surface is confirmed in the imaging data, the damaged part can be processed and the damaged part can be marked.
At this time, the marked portion can be confirmed on the map. As a result, the damaged part can be easily confirmed by looking at the entire map.

The data processing unit 22 is a computer that controls each unit of the road surface evaluation system 1, and may be, for example, a central processing unit (CPU), a microprocessor, an ASIC, an FPGA, or the like. The data processing unit 22 is not limited to these examples, and may be any computer as long as it controls each unit of the road surface evaluation system 1.

As shown in FIG. 2, the data processing unit 22 includes a data search unit 23, a parameter calculation unit 24, and a data correction unit 25.
The data search unit 23 reads the imaging data and the position data from the storage unit 21 and displays them on the display unit 26. The data search unit 23 can search the imaging data stored in the storage unit 21 by inputting, for example, an inspection route identification number, a shooting date and time, etc. input by the user to the operation terminal 20.

Further, in the present embodiment, the data search unit 23 determines the similarity between the position data stored in correspondence with the plurality of imaging data stored in the storage unit 21 and the progress vector. Then, the data processing unit 22 has a function of reading the comparison source imaging data and the comparison destination imaging data in which the road surface of the same location is imaged from the storage unit 21. This function will be described in detail below.

The parameter calculation unit 24 calculates a travel vector indicating the traveling direction of the inspection vehicle 100 at the time when the imaging data is captured from the amount of change in the position data at predetermined time intervals.
The travel vector indicates the direction in which the inspection vehicle 100 faces. Then, since the action camera 10 faces the front of the inspection vehicle 100, the direction in which the imaging unit 11 is capturing is specified by specifying the traveling vector.

The parameter calculation unit 24 calculates the progress vector at the reference time by comparing the position information at the reference time with the position information after a predetermined time. The calculated progress vector is stored in the storage unit 21 as a part of the attribute data.
Then, the data search unit 23 refers to the position data associated with the imaging data and the progress vector, and reads the comparison source imaging data and the comparison destination imaging data from the storage unit 21.

Here, the comparison source imaging data and the comparison destination imaging data each refer to still image data for each unit frame constituting the moving image data acquired by the imaging unit 11.
The comparison source imaging data refers to imaging data at a reference time. The reference time may be the present or a predetermined date and time in the past.
The comparison destination imaging data refers to imaging that is compared with the comparison source imaging data, and refers to data in which a portion of the comparison source imaging data that is particularly desired to be observed is captured. The comparison destination imaging data may be data that is older than the comparison source imaging data, or may be future data.

The parameter calculation unit 24 sets a position threshold value by adding a predetermined position range to the position data associated with the comparison source imaging data. As a predetermined position range, for example, a range of ± 0.5 m can be set. The value of the predetermined position range can be changed arbitrarily.

Further, the parameter calculation unit 24 sets an angle threshold value by adding a predetermined angle range to the progress vector. As the predetermined angle range, for example, a range of ± 15 ° can be set. The value in the predetermined angle range can be changed arbitrarily.
Then, the data search unit 23 compares the imaging data stored in the storage unit 21 with the imaging data having the position data within the position threshold and the progress vector within the angle threshold with high similarity to the comparison source imaging data. It is read from the storage unit 21 as the pre-image data.

The data correction unit 25 geometrically corrects the imaging data read by the data search unit 23. By geometrically correcting the imaging data by the data processing unit 22, it is possible to match the viewpoints of a plurality of imaging data acquired by imaging while the traveling vehicle is traveling.
As a result, it is possible to acquire the corrected comparison destination imaging data with high distinctiveness of the damaged portion, as if the fixed point observation was performed from the same observation point as the comparison source imaging data. The geometric correction process by the data correction unit 25 will be described in detail with reference to FIGS. 7 and 8. FIG. 7A is a diagram for explaining the elevation / depression angle of the imaging unit 11, and FIG. 7B is a diagram for explaining a three-dimensional virtual area. FIG. 8 is a diagram illustrating calibration of the imaging unit 11.

As shown in FIG. 7A, the imaging unit 11 is set so that the point 5 m ahead is at the center of the angle of view. At this time, the imaging unit 11 can image the region having a triangle in FIG. 7 (b).
Then, the data correction unit 25 sets a three-dimensional virtual area for the imaged data. The three-dimensional virtual area is an area defined in front of the inspection vehicle 100, and refers to an area outlined in FIG. 7B.

Specifically, the position of the imaging unit 11 is set as the origin, and the region from the origin to a predetermined distance forward and the region to both ends in the left-right direction of the road is defined as a three-dimensional virtual region. That is, the three-dimensional virtual area includes a range that has not been imaged by the imaging unit 11.
The three-dimensional virtual area is defined by the first vertex, the second vertex, the third vertex, and the fourth vertex. The distance between the first vertex and the second vertex is 5 m (predetermined distance). The distance between the first vertex and the fourth vertex is 4 m, and the distance between the first vertex and the origin is 2 m. The predetermined distance between the first vertex and the second vertex does not have to be 5 m, and the distance between the first vertex and the origin does not have to be 2 m. That is, the size of the three-dimensional virtual area can be changed arbitrarily.

The data correction unit 25 calculates the viewpoint information indicating the position of the viewpoint of the imaging data by using the coordinates of each vertex that divides the three-dimensional virtual area. At this time, the data correction unit 25 records the coordinate information of each vertex of the three-dimensional virtual area by using the position information acquired from the positioning system 12 at the time of shooting, and sets the coordinates that define the three-dimensional virtual area in the imaging data. It is memorized in the added state.

As shown in FIG. 8, as a calibration, it is confirmed at which position each vertex defining the three-dimensional virtual area is located in the imaging data.
Specifically, the relationship between the pixel coordinates in the imaging data and the spatial coordinates obtained with the actual imaging unit 11 as the origin is confirmed. At this time, the first and fourth vertices located behind may not be imaged.

Next, the data correction unit 25 uses the viewpoint information (viewpoint coordinates and line-of-sight direction) to perform geometric correction on the comparison destination imaging data so as to be the viewpoint of the comparison source imaging data, thereby performing the comparison source imaging. Generate comparison destination correction imaging data to be compared with the data.
In this process, the data correction unit 25 calculates the viewpoint information (viewpoint coordinates and line-of-sight direction) using the coordinate information of each vertex of the three-dimensional virtual area with respect to the comparison source imaging data. Next, the data correction unit 25 calculates the viewpoint information (viewpoint coordinates and line-of-sight direction) using the coordinate information of each vertex of the three-dimensional virtual area with respect to the comparison destination imaging data.
Next, the data correction unit 25 uses the viewpoint information of the comparison destination imaging data and the viewpoint information of the comparison source imaging data to project a projection for matching the viewpoint of the comparison destination imaging data with the viewpoint of the comparison source imaging data. Calculate the transformation matrix.

Then, the data correction unit 25 performs geometric correction on the comparison destination imaging data so as to be the viewpoint of the comparison source imaging data. At this time, geometric correction is performed on all the pixels constituting the comparison destination imaging data by using the projective transformation matrix calculated in advance. As a result, the comparison destination correction imaging data is generated in which the viewpoint matches the comparison source imaging data and the comparison is easy.
Since the comparison source data and the viewpoint information of the comparison destination correction imaging data corrected in this way match, for example, by performing overlay processing, it is possible to accurately grasp the state of secular change.

(Processing flow)
Next, the processing flow of the road surface evaluation system 1 will be described with reference to FIGS. 9 and 10. FIG. 9 is a flow chart showing a process of reading the data stored in the storage unit 21 by the data search unit 23, and FIG. 10 is a flow chart showing a process of performing geometric correction by the data correction unit 25. First, a process of reading the data stored in the storage unit 21 by the data search unit 23 will be described.

As shown in FIG. 9, first, the imaging unit 11 acquires imaging data (S101). At this time, the inspection vehicle 100 travels on the evaluation route as the defined route area.
Imaging data can be acquired by imaging the state of the road surface ahead by the imaging unit 11 while traveling on the evaluation route. The action camera 10 has the camera position and elevation / depression angle set in advance before traveling.

Next, the positioning system 12 acquires the position information (S102). The positioning system 12 acquires position information including at least latitude and longitude from GPS satellites 30. Then, the transmitting unit 13 transmits the imaging data and the position information (S103), and the receiving unit 27 receives the imaging data and the position information (S104).
The data processing unit 22 stores the imaging data and the position information in the storage unit 21 (S105: storage step). At this time, the position information is stored as attribute information for each shooting time.

Next, the parameter calculation unit 24 calculates each parameter including the progress vector (S106: parameter calculation step). The progress vector is calculated for each imaging data for each imaging time. Each parameter is a moving distance, a traveling speed, a traveling vector, and the coordinates of each vertex in the three-dimensional virtual area. Each of these parameters is stored in the storage unit 21 as attribute data as shown in FIG.

Next, the parameter calculation unit 24 calculates the position threshold value (S107). The position threshold is calculated for each imaging data for each imaging time. A predetermined position range used for calculating the position threshold value can be arbitrarily set. The parameter calculation unit 24 stores the calculated position threshold value in the storage unit 21.

Next, the parameter calculation unit 24 calculates the angle threshold value (S108). The angle threshold value is calculated for each imaging data for each imaging time. The predetermined angle range used for calculating the angle threshold value can be arbitrarily set. The parameter calculation unit 24 stores the calculated angle threshold value in the storage unit 21.

Next, the data search unit 23 reads the comparison source imaging data (S109: data search step). The comparison source imaging data is specified and searched by information such as the shooting time and the evaluation route input by the user.
The comparison source imaging data may be, for example, the latest imaging data or past imaging data. The comparison source imaging data is, for example, imaging data including a portion having an adverse effect on the function of the road surface such as a dent called a pothole formed on the road surface. Then, by comparing the comparison source imaging data and the comparison destination imaging data, it is possible to confirm the state of the secular change of this pothole.

Next, the data search unit 23 reads the comparison destination imaging data (S110: data search step). The comparison destination imaging data is imaging data having high similarity to the comparison source imaging data.
The data search unit 23 reads the position data within the position threshold value and the imaging data having the progress vector within the angle threshold value from the storage unit 21 as comparison destination imaging data having high similarity to the comparison source imaging data. As a result, it is possible to acquire imaging data whose position is close to that of the comparison source imaging data and whose imaging direction is close.

Next, the geometric correction process performed by the data correction unit 25 will be described.
As shown in FIG. 10, first, the data correction unit 25 sets a three-dimensional virtual area in the comparison source imaging data (S201). The three-dimensional virtual area is defined in advance by the relationship between the pixel coordinates in the imaging data and the spatial coordinates obtained with the actual imaging unit 11 as the origin.
Next, the data correction unit 25 calculates the viewpoint information (S202). When calculating the viewpoint information, the calculation is performed using the coordinates of each vertex of the three-dimensional virtual area. Each of the calculated coordinates is stored in the storage unit 21 as a part of the attribute data (see FIG. 4).

Next, as shown in FIG. 10, the data correction unit 25 sets a three-dimensional virtual area in the comparison destination imaging data (S203). The three-dimensional virtual area is defined in advance by the relationship between the pixel coordinates in the imaging data and the spatial coordinates obtained with the actual imaging unit 11 as the origin.
Next, the data correction unit 25 calculates the viewpoint information (S204). When calculating the viewpoint information, the calculation is performed using the coordinates of each vertex of the three-dimensional virtual area.
Then, the data correction unit 25 calculates the projective transformation matrix (S205). The projective transformation matrix is calculated using two viewpoint information calculated from each of the comparison destination imaging data and the comparison source imaging data.

Next, the data correction unit 25 performs geometric correction on the comparison destination imaging data (S206). The data correction unit 25 is performed using a projective transformation matrix. As a result, the viewpoint information of the comparison destination imaging data matches the viewpoint information of the comparison source imaging data, and the comparison destination correction imaging data as if observed from the same viewpoint is generated. Next, the data correction unit 25 stores the generated comparison destination correction imaging data in the storage unit 21 (S207).

Finally, the display unit 26 displays the comparison source imaging data and the comparison destination correction imaging data (S208). At this time, the comparison source imaging data and the comparison destination correction imaging data may be displayed in a superposed state, or may be displayed in a state of being arranged side by side. As a result, by simultaneously confirming the comparison source imaging data and the comparison destination correction imaging data, it is possible to confirm the secular change of the portion that adversely affects the function of the road surface.

As described above, according to the road surface evaluation system 1 according to the present embodiment, the data search unit 23 refers to the position data associated with the imaging data and the progress vector of the inspection vehicle 100 in the storage unit 21. Compare a plurality of stored imaging data.
As a result, the data search unit 23 can read the comparison source imaging data and the comparison destination imaging data in which the road surface at the same location is imaged from the storage unit 21. Therefore, by confirming and comparing the comparison source imaging data and the comparison destination imaging data, for example, when the comparison destination imaging data is taken after the comparison source imaging data, the time passes. It is possible to grasp how the road surface changes over time.

Further, the data processing unit 22 sets a position threshold value for the position data, and the data search unit 23 stores the position data within the position threshold value as the comparison destination imaging data having high similarity to the comparison source imaging data. Read from. As a result, among the large amount of stored imaging data, it is possible to easily identify the imaging data whose imaging point is close to the comparison source imaging data.

Further, the data processing unit 22 sets an angle threshold value with respect to the progress vector, and the data search unit 23 uses the image pickup data having the progress vector within the angle threshold value as the comparison destination imaging data having a high similarity to the comparison source imaging data. Is read from the storage unit 21.
As a result, even if the imaging data is close to the comparison source imaging data, the imaging data whose imaging direction is significantly different from that of the imaging unit 11 is excluded, so that noise is removed from the search process of the data search unit 23. Can be removed.

Further, since the imaging unit 11 is arranged at the center in the left-right direction in front of the inspection vehicle 100 so as to face the front of the inspection vehicle 100, the left and right sides of the inspection vehicle 100 can be uniformly imaged.

Further, the data correction unit 25 calculates the viewpoint information indicating the position of the viewpoint of the imaging data using the coordinates of each vertex that divides the three-dimensional virtual area set in the imaging data, and uses the viewpoint information to compare the comparison destination. Geometric correction is performed on the imaged data so that it becomes the viewpoint of the comparison source imaged data.
As a result, the viewpoint information is calculated in advance and applied to all the pixel data, for example, a method of calculating the viewpoint information for each pixel constituting the comparison destination imaging data and performing geometric correction. In comparison, the calculation load related to geometric correction can be significantly reduced. As a result, the road surface evaluation system 1 can be realized at low cost by a computer such as a general-purpose personal computer, and the processing speed can be secured.

It should be noted that the above-described embodiment is merely an example of a typical embodiment of the present invention. Therefore, various modifications may be made to the above-described embodiment without departing from the spirit of the present invention.

For example, the structure of the attribute data shown in the above embodiment is merely an example. These data structures can be changed arbitrarily.
Further, the display content on the display unit 26 of the operation terminal 20 shown in the above embodiment is merely an example. The display content on the display unit 26 can be arbitrarily changed.

Further, in the above embodiment, a configuration for defining a rectangular area as a three-dimensional virtual area has been described, but the present invention is not limited to such a mode. The three-dimensional virtual area may be a plane figure other than a rectangle.
Further, in the above embodiment, the mode in which the data correction unit 25 calculates the projective transformation matrix and performs geometric correction using this matrix has been described, but the present invention is not limited to such a mode. The data correction unit 25 may simply perform correction to match the reference coordinates without calculating the projection transformation matrix.

Further, the control program used in the road surface evaluation system 1 may be provided in a state of being stored in a storage medium readable by a computer. The storage medium can store the control program in a "non-temporary tangible medium".
The storage medium can include any suitable storage medium such as HDD or SDD, or a suitable combination of two or more thereof. The storage medium may be volatile, non-volatile, or a combination of volatile and non-volatile. The storage medium is not limited to these examples, and may be any device or medium as long as the control program can be stored.

Further, the road surface evaluation system 1 may be configured to realize each function shown in the embodiment by reading the control program stored in the storage medium and executing the read control program. Further, the control program may be provided to the road surface evaluation system 1 via an arbitrary transmission medium (communication network, broadcast wave, etc.). The road surface evaluation system 1 may be configured to realize the various functions described above by executing a control program downloaded via the Internet or the like, for example.

Further, the control program may be implemented using, for example, a script language such as ActionScript or JavaScript (registered trademark), an object-oriented programming language such as Objective-C or Java (registered trademark), or a markup language such as HTML5. Good.

Further, in the above embodiment, the road surface evaluation system 1 shows a configuration realized by the action camera 10 and the operation terminal 20, but the present invention is not limited to such a mode. The road surface evaluation system 1 may not include the action camera 10 and may be configured only by the operation terminal 20 that analyzes the acquired imaging data and the position information.

Further, at least a part of the processing in the road surface evaluation system 1 may be realized by cloud computing composed of one or more computers. Further, each functional unit of the road surface evaluation system 1 may be realized by one or a plurality of circuits that realize the functions shown in the above embodiment, and the functions of the plurality of functional units are realized by one circuit. May be good.

Moreover, although the embodiment of the present disclosure has been described based on various drawings and examples, those skilled in the art can easily make various modifications and modifications based on the present disclosure. Therefore, these modifications and modifications are included in the scope of the present disclosure. For example, the functions included in each means, each step, etc. can be rearranged so as not to be logically inconsistent, and a plurality of means, steps, etc. can be combined or divided into one. .. Further, the configurations shown in each embodiment may be appropriately combined.

1 Road surface evaluation system 10 Action camera 11 Imaging unit 12 Positioning system 20 Operation terminal 21 Storage unit 22 Data processing unit 23 Data search unit 24 Parameter calculation unit 25 Data correction unit 100 Inspection vehicle

Claims (6)

The imaging data mounted on the inspection vehicle traveling on the road surface to be inspected and acquired from the imaging unit that images the state of the road surface around the vehicle was acquired from the positioning system that specifies the position data indicating the position of the inspection vehicle. A storage unit that stores in association with position data,
A data processing unit that reads the imaging data and the position data from the storage unit is provided.
The data processing unit includes a parameter calculation unit that calculates a travel vector indicating the traveling direction of the inspection vehicle at the time when the imaging data is captured from the amount of change in the position data at predetermined time intervals.
The comparison source imaging data and the comparison destination in which the road surface at the same location is imaged by referring to the position data associated with the plurality of imaging data stored in the storage unit and the traveling vector to determine the similarity between them. A road surface evaluation system including a data search unit that reads captured data from the storage unit. The parameter calculation unit
A position threshold value is set by adding a range of a predetermined position to the position data associated with the comparison source imaging data.
An angle threshold value with a predetermined angle range added to the traveling vector is set.
Among the imaging data, the data search unit uses the imaging data having the position data within the position threshold value and the progress vector within the angle threshold value as the comparison destination imaging data having high similarity to the comparison source imaging data. The road surface evaluation system according to claim 1, wherein the data is read from the storage unit. The road surface evaluation system according to claim 1 or 2, wherein the imaging unit is arranged at a central portion in the left-right direction in front of the inspection vehicle so as to face the front of the inspection vehicle. The data processing unit includes a data correction unit that corrects the imaging data read by the data search unit.
The data correction unit sets a three-dimensional virtual area for the imaged data,
Using the coordinates of each vertex that divides the three-dimensional virtual area, viewpoint information indicating the position of the viewpoint of the imaging data is calculated.
Using the viewpoint information, the comparison destination imaging data is geometrically corrected so as to be the viewpoint of the comparison source imaging data, thereby generating comparison destination correction imaging data to be compared with the comparison source imaging data. The road surface evaluation system according to claim 3, wherein the road surface evaluation system is characterized in that. The computer
The imaging data mounted on the inspection vehicle traveling on the road surface to be inspected and acquired from the imaging unit that images the state of the road surface around the vehicle was acquired from the positioning system that specifies the position data indicating the position of the inspection vehicle. A storage step that associates with position data and stores it in the storage unit,
A data processing step of reading the imaged data and the position data from the storage unit is executed.
The data processing step includes a parameter calculation step of calculating a progress vector indicating the traveling direction of the inspection vehicle at the time when the imaging data is captured from the amount of change of the position data at predetermined time intervals.
The comparison source imaging data and the comparison destination in which the road surface at the same location is imaged by referring to the position data associated with the plurality of imaging data stored in the storage unit and the traveling vector to determine the similarity between them. A road surface evaluation method including a data search step for reading captured data from the storage unit. On the computer
The imaging data mounted on the inspection vehicle traveling on the road surface to be inspected and acquired from the imaging unit that images the state of the road surface around the vehicle was acquired from the positioning system that specifies the position data indicating the position of the inspection vehicle. A storage function that associates with position data and stores it in the storage unit,
A data processing function for reading the imaged data and the position data from the storage unit, and
Realized,
The data processing function includes a parameter calculation function that calculates a travel vector indicating the traveling direction of the inspection vehicle at the time when the imaging data is captured from the amount of change of the position data at predetermined time intervals.
The comparison source imaging data and the comparison destination in which the road surface at the same location is imaged by referring to the position data associated with the plurality of imaging data stored in the storage unit and the traveling vector to determine the similarity between them. A road surface evaluation program having a data search function for reading captured data from the storage unit.

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