Position information processing apparatus and position information processing method

Abstract

To provide a position information processing device that corrects a three-dimensional point cloud group so as to make two three-dimensional point cloud groups comparable.SOLUTION: A position information processing device determines a separate section in which a first reference line of a first three-dimensional point cloud group and a second reference line of a second three-dimensional point cloud group are separate, associates a first reference point in the separate section of the first reference line with the first three-dimensional point cloud group, correlates a first reference point in the separate section of the first reference line to a second reference point of the second reference line, corrects the position of the first three-dimensional point cloud group using a difference in position with the correlated second reference point with regard to the first reference point in the separate section of the first reference line, generates a reference straight line on the basis of the first reference point in the separate section of the first reference line and arranges the second reference point of the second reference line on the reference straight line, and corrects the position of the first three-dimensional point cloud group using a difference in position with a point on the reference straight line with regard to the first reference point in the separate section of the first reference line and corrects the position of the second three-dimensional point cloud group using a difference in position with a point on the reference straight line with regard to the second reference point in the separate section of the second reference line.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a location information processing device and a location information processing method. [Background technology]

[0002] Conventionally, the route along which a vehicle such as an automobile or a train travels and the position of the surrounding environment are measured as a three-dimensional point cloud using a measurement vehicle. Based on the measured three-dimensional point cloud, for example, a high-precision map including roads and the surrounding environment is created.

[0003] FIG. 1(A) is a diagram showing a measurement vehicle, and FIG. 1(B) is a diagram showing a state in which measurement is performed using the measurement vehicle.

[0004] The measurement vehicle 100 includes a GNSS device 101, an IMU device 102, an odometry device 103, a laser scanner 104, and a camera 105. The GNSS device 101 receives radio waves from GNSS positioning satellites and estimates the position and attitude of the measurement vehicle 100. The IMU device 102 estimates the position and attitude of the measurement vehicle 100 based on the outputs of an accelerometer and an gyroscope arranged on the measurement vehicle 100. The odometry device 103 estimates the position and attitude of the measurement vehicle 100 based on the speed of the measurement vehicle 100 and the output of the gyroscope. The position and attitude of the measurement vehicle 100 are estimated based on the measurement results of the GNSS device 101, the IMU device 102, and the odometry device 103. The position and attitude of the measurement vehicle 100 are expressed, for example, in a world coordinate system with a predetermined position as the origin.

[0005] While traveling along a predetermined travel route, the measurement vehicle 100 uses a laser scanner 104 to scan the surroundings of the measurement vehicle 100 with a laser at measurement times having a predetermined cycle, and measures the distance and direction relative to the measurement vehicle 100 for a number of positions representing the travel route and the surrounding environment. The measurement vehicle 100 also takes images of the travel route and the surrounding environment using a camera 105.

[0006] Further, the measurement vehicle 100 measures the position and orientation of the measurement vehicle 100 at the time when the laser is scanned, using the GNSS device 101, the IMU device 102, and the odometry device 103.

[0007] The positions of the driving route and the surrounding environment are represented in the world coordinate system based on the relative distances and orientations with respect to the measurement vehicle 100 measured by the laser scanning, and the position and orientation information of the measurement vehicle 100 at the time of laser scanning.

[0008] In this way, a three-dimensional point cloud representing the positions of the driving route and the surrounding environment is obtained along the driving route of the measurement vehicle 100.

[0009] Here, there may be a case where radio waves from the GNSS positioning satellites are blocked from the measurement vehicle 100 by a tunnel or a high-rise building. When the radio waves from the positioning satellites are blocked from the measurement vehicle 100, the accuracy of the position and orientation of the measurement vehicle 100 may decrease.

[0010] Although the measurement accuracy of the positions of the driving route and the surrounding environment with respect to the measurement vehicle 100 measured by laser scanning is considered to be high, the accuracy of the position and orientation of the measurement vehicle 100 at the time of laser scanning decreases, resulting in a decrease in the accuracy of the positions of the three-dimensional point cloud representing the surrounding environment of the driving route. Therefore, it has been proposed to correct the positions of the measured three-dimensional point cloud (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0011]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0012] Since the driving route and the surrounding environment can change, the same position of the driving route and the surrounding environment may be measured at different times. As a result, two three-dimensional point clouds are obtained.

[0013] However, as described above, mainly due to the accuracy of the position and attitude information of the measurement vehicle 100, the positions representing the driving route and the surrounding environment may be different between the two three-dimensional point clouds measured for the same driving route.

[0014] In order to examine the changes in the driving route and the surrounding environment, it is necessary to correct the three-dimensional point cloud so that the two three-dimensional point clouds can be compared.

[0015] Therefore, this specification aims to provide a position information processing device that corrects a three-dimensional point cloud so that two separately measured three-dimensional point clouds can be compared.

Means for Solving the Problem

[0016] According to one embodiment, a position information processing apparatus is provided. This position information processing apparatus is configured for a first reference line representing a predetermined linear environment set for a first three-dimensional point cloud representing the position of the environment around a first driving route of a first vehicle collected by scanning a laser scanner mounted on the first vehicle, and a second three-dimensional point cloud representing the position of the environment around a second driving route including at least a partially same route as the first driving route collected by scanning a laser scanner mounted on a second vehicle. It has a start position at which the distance between the first reference line and a second reference line representing a predetermined linear environment corresponding to the first reference line starts to be separated by more than a predetermined first reference distance, a section determination unit that determines a separation section in which the distance between the first reference line and the second reference line representing a predetermined linear environment corresponding to the first reference line is separated by more than the first reference distance, an association unit that associates each of a plurality of first reference points forming the separation section of the first reference line with a point included in the first three-dimensional point cloud, a correspondence unit that associates each of the plurality of first reference points forming the separation section of the first reference line with a second reference point forming the separation section of the second reference line, a first correction unit that obtains the difference in position between each of the plurality of first reference points forming the separation section of the first reference line and the second reference point associated with the first reference point, and uses the difference in position to correct the position of the point included in the first three-dimensional point cloud associated with the first reference point, a straight line generation unit that arranges each of the plurality of first reference points forming the separation section of the first reference line to extend in a predetermined direction starting from the start position so that the distance between adjacent first reference points is maintained to generate a reference straight line, and arranges each of the plurality of second reference points forming the separation section of the second reference line on the reference straight line starting from the start position so that the distance between adjacent second reference points is maintained, and a second correction unit that obtains the difference in position between each of the plurality of first reference points forming the separation section of the first reference line and the point on the reference straight line corresponding to the first reference point, uses the difference in position to correct the position of the point included in the first three-dimensional point cloud associated with the first reference point, and for each of the plurality of second reference points forming the separation section of the second reference line, obtains the difference in position between the second reference point and the point on the reference straight line corresponding to the second reference point, and uses the difference in position to correct the position of the point included in the second three-dimensional point cloud associated with the second reference point.

[0017] According to another embodiment, a position information processing method is provided. This position information processing method is for a first reference line representing a predetermined linear environment set for a first three-dimensional point cloud representing the positions of the environments around a first driving route of a first vehicle, which is collected by scanning a laser scanner mounted on the first vehicle, and a second three-dimensional point cloud representing the positions of the environments around a second driving route including at least a partially same route as the first driving route, which is collected by scanning a laser scanner mounted on a second vehicle. The method starts when the distance between the first reference line and a second reference line representing a predetermined linear environment corresponding to the first reference line is separated by more than a predetermined first reference distance. The method determines a separation section where the distance between the first reference line and the second reference line representing a predetermined linear environment corresponding to the first reference line is separated by more than the first reference distance, associates each of a plurality of first reference points forming the separation section of the first reference line with a point included in the first three-dimensional point cloud, associates each of the plurality of first reference points forming the separation section of the first reference line with a second reference point forming the separation section of the second reference line, obtains the difference in position between the second reference point associated with each of the plurality of first reference points forming the separation section of the first reference line and the corresponding first reference point, corrects the position of the point included in the first three-dimensional point cloud associated with the first reference point using the difference in position, arranges each of the plurality of first reference points forming the separation section of the first reference line to extend in a predetermined direction starting from the start position so that the distance between adjacent first reference points is maintained, thereby generating a reference line, and arranges each of the plurality of second reference points forming the separation section of the second reference line on the reference line starting from the start position so that the distance between adjacent second reference points is maintained. For each of the plurality of first reference points forming the separation section of the first reference line, the difference in position between the point on the reference line corresponding to the first reference point and the first reference point is obtained, and the position of the point included in the first three-dimensional point cloud associated with the first reference point is corrected using the difference in position. For each of the plurality of second reference points forming the separation section of the second reference line, the difference in position between the point on the reference line corresponding to the second reference point and the second reference point is obtained, and the position of the point included in the second three-dimensional point cloud associated with the second reference point is corrected using the difference in position.

Effect of the Invention

[0018] According to the position information processing apparatus and the position information processing method disclosed in the present specification described above, the three-dimensional point cloud can be corrected so that two separately measured three-dimensional point clouds can be compared.

Brief Description of the Drawings

[0019]

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Best Mode for Carrying Out the Invention

[0020] Hereinafter, a preferred embodiment of the position information processing apparatus disclosed in this specification will be described with reference to the drawings.

[0021] FIG. 2 is a schematic configuration diagram of the position information processing apparatus 10 according to this embodiment. The position information processing apparatus 10 corrects one three-dimensional point group so that two separately measured three-dimensional point groups can be compared. The two three-dimensional point groups represent the position of the traveling route and the surrounding environment measured by the measurement vehicle as shown in FIG. 1 on a traveling route that includes at least partially the same route. The two three-dimensional point groups may be measured by different measurement vehicles, or may be measured by the same measurement vehicle at different timings.

[0022] The position information processing apparatus 10 includes a communication interface (IF) 21, a user interface (UI) 22, a memory 23, and a processor 24. The communication IF 21, the UI 22, the memory 23, and the processor 24 are connected via a communication line 25.

[0023] The communication IF 21 has an interface circuit for connecting the position information processing apparatus 10 to a network (not shown). The data of the two three-dimensional point groups is input to the position information processing apparatus 10 from, for example, the measurement vehicle 100 via the network.

[0024] The UI 22 inputs a user operation to generate an operation signal and outputs the processing result of the position information processing apparatus 10. The UI 22 has, as an input device for inputting a user operation, for example, a keyboard, a mouse, or a touch panel. The UI 22 has, as an output device for outputting the processing result, a display device such as a liquid crystal display or a touch panel.

[0025] The memory 23 is an example of a storage unit and has, for example, a volatile semiconductor memory and a non-volatile semiconductor memory. The memory 23 stores a computer program for the processor 24 to execute position information processing and data generated in the position information processing.

[0026] Further, the memory 23 stores data of a first three-dimensional point cloud representing the positions of the environment around the first driving route of the first measurement vehicle collected by scanning a laser scanner mounted on the first measurement vehicle, and data of a second three-dimensional point cloud representing the positions of the environment around the second driving route including at least a partially same route as the first driving route collected by scanning a laser scanner mounted on the second measurement vehicle.

[0027] The processor 24 has one or more CPUs (Central Processing Units) and its peripheral circuits. The processor 24 may further have other arithmetic circuits such as a logical operation unit, a numerical operation unit, or a graphic processing unit.

[0028] All or part of the functions of the position information processing apparatus 10 are, for example, functional modules realized by a computer program operating on the processor 24. The processor 24 has a reference line setting unit 31, a section determination unit 32, an association unit 33, a correspondence unit 34, a correction unit 35, and a straight line generation unit 36. Alternatively, the functional modules of the processor 24 may be dedicated arithmetic circuits provided in the processor 24.

[0029] FIG. 3 is an operation flowchart regarding the position information processing of the position information processing apparatus 10. First, the reference line setting unit 31 reads the data of the first three-dimensional point group and the second three-dimensional point group from the memory 23, sets a first reference line representing a predetermined linear environment for the first three-dimensional point group, and sets a second reference line representing an environment corresponding to the first reference line for the second three-dimensional point group (step S101). FIG. 4 is a diagram showing the first reference line R1 and the second reference line R2. The first reference line is set based on the position or travel route of the environment measured by the first measurement vehicle, and the second reference line is set based on the position or travel route of the environment measured by the second measurement vehicle.

[0030] The reference line setting unit 31 may set the first reference line R1 for the first three-dimensional point group using a plurality of points in the first three-dimensional point group, and set the second reference line R2 using a plurality of points in the second three-dimensional point group.

[0031] For example, the reference line setting unit 31 sets the first reference line R1 based on points having a reflection intensity of a laser scanner equal to or higher than a predetermined threshold among the first three-dimensional point group included in a predetermined area determined based on the position information representing the travel trajectory of the first measurement vehicle, and sets the second reference line R2 based on points having a reflection intensity of a laser scanner equal to or higher than the predetermined threshold among the second three-dimensional point group included in the predetermined area determined based on the position information representing the travel trajectory of the second measurement vehicle. When the first measurement vehicle and the second measurement vehicle are automobiles, as the predetermined area, an area including the center line of the road on which the first measurement vehicle and the second measurement vehicle have traveled can be used.

[0032] Further, when the first measurement vehicle and the second measurement vehicle are railway vehicles, the reference line setting unit 31 may set a first reference line R1 based on points representing the track on which the first measurement vehicle travels among the first three-dimensional point cloud, and set a second reference line R2 based on points representing the track on which the second measurement vehicle travels among the second three-dimensional point cloud. The reference line setting unit 31 may be configured to include a discriminator that has learned to input a three-dimensional point cloud and detect points representing the track of a railway vehicle. This discriminator inputs a three-dimensional point cloud and detects points representing the track of a railway vehicle.

[0033] Further, the first reference line and the second reference line may be given by a user instead of being set by the reference line setting unit 31. For example, when the first measurement vehicle and the second measurement vehicle are railway vehicles and the first travel route and the second travel route include the same track, the travel route of the first measurement vehicle measured by the first measurement vehicle may be set as the first reference line R1, and the travel route of the second measurement vehicle measured by the second measurement vehicle may be set as the second reference line R2.

[0034] Next, the section determination unit 32 determines a start position at which the distance between the first reference line R1 and the second reference line R2 starts to deviate from a predetermined first reference distance, and a separation section in which the distance between the first reference line R1 and the second reference line R2 corresponding to a predetermined linear environment is greater than the first reference distance (step S102). If there is an end position at which the distance between the first reference line R1 and the second reference line R2 ends deviating from a predetermined reference distance, the section determination unit 32 may determine this end position. In the example shown in FIG. 4, a separation section D is set between the start position P1 and the end position P2. As the first reference distance, for example, a distance of 0.1 m to 3 m can be set.

[0035] Note that the first reference line R1 and the second reference line R2 extending from the start position may not intersect each other. In this case, the separation section means a section from the start position until the open ends where the first reference line R1 and the second reference line R2 remain separated.

[0036] Next, the association unit 33 associates each of the plurality of first reference points forming the separation interval D of the first reference line R1 with a point included in the first three-dimensional point group (step S103). The first reference line R1 is divided into a plurality of first reference points, for example, based on the interval of the distance corresponding to the measurement time when the first three-dimensional point group is measured. Alternatively, the first reference line R1 may be divided into a plurality of first reference points at predetermined distance intervals.

[0037] FIG. 5 is a diagram for explaining the association process. The association unit 33 associates, for example, each of the plurality of first reference points forming the separation interval D, with the points of the first three-dimensional point group included in the cross section 500 that includes this first reference point and is orthogonal to the first reference line R1.

[0038] Also, when the first reference line R1 is set using a plurality of points in the first three-dimensional point group, the association unit 33, for each of the plurality of first reference points forming the separation interval D of the first reference line R1, may associate the point included in the first three-dimensional point group whose position was measured at the same time as the time when this first reference point was measured, with this first reference point. When the first reference line R1 is set using a plurality of points in the first three-dimensional point group, the first reference point is associated with the point (itself) of the first three-dimensional point group representing this first reference point.

[0039] Next, the pairing unit 34 pairs each of the plurality of first reference points forming the separation interval D of the first reference line R1 with a second reference point forming the separation interval D of the second reference line R2 (step S104). FIGS. 6(A) to 6(C) are diagrams for explaining the pairing process.

[0040] As shown in FIG. 6(A), the pairing unit 34 may pair, for each of the plurality of first reference points forming the separation interval D of the first reference line R1, with the second reference point located at the position closest to this first reference point.

[0041] Further, as shown in FIG. 6(B), for each of the plurality of first reference points forming the separation interval D, the association unit 34 may associate a second reference point such that the ratio l1 / L1 of the distance l1 from the start position P1 to this first reference point to the distance L1 of the separation interval D on the first reference line R1 is equal to the ratio l2 / L2 of the distance l2 from the start position P1 to the second reference point to the distance L2 of the separation interval D on the second reference line R2.

[0042] As shown in FIG. 6(C), at the stage where this association process is performed, the second reference point on the second reference line R2 associated with the first reference point is considered to have a deviation along the second reference line R2 and / or a rotational angle deviation with the second reference line R2 as the rotation axis from the position of the actual travel route and the surrounding environment represented by the first reference point. These deviations are corrected in the process described later.

[0043] Next, the correction unit 35 obtains the position difference H (see FIG. 6(C)) between each of the plurality of first reference points forming the separation interval D of the first reference line R1 and the second reference point associated with this first reference point, and uses this position difference H1 to correct the positions of the points included in the first three-dimensional point group associated with this first reference point (step S105).

[0044] The matrix for converting the first reference point to the associated second reference point (hereinafter also referred to as the first correction matrix) is represented by a combination of a translation matrix representing translation and a rotation matrix representing rotation. The position correction using the position difference H1 can be represented by this first correction matrix. The correction unit 35 uses the first correction matrix to correct the positions of the points included in the first three-dimensional point group associated with each of the plurality of first reference points forming the separation interval D of the first reference line R1. When the first reference line R1 is set using a plurality of points of the first three-dimensional point group, the positions of the points of the first three-dimensional point group forming the first reference line R1 are also corrected using the first correction matrix.

[0045] Next, the straight line generation unit 36 arranges each of the plurality of first reference points that form the separation interval D of the first reference line R1 so as to extend in a predetermined direction starting from the start position P1 while maintaining the distance between adjacent first reference points, thereby generating a reference straight line R3. Further, each of the plurality of second reference points that form the separation interval D of the second reference line R1 is arranged on the reference straight line R3 starting from the start position P1 so as to maintain the distance between adjacent second reference points (step S106). As the plurality of second reference points, the points associated with the first reference points in the above-described association process can be used. As the predetermined direction, an arbitrary direction is given in advance.

[0046] FIG. 7 is a diagram for explaining the straight line generation process. Each of the plurality of first reference points that form the separation interval D is arranged on a reference straight line R3 that extends in a predetermined direction starting from the start position P1 while maintaining the distance between adjacent first reference points. Similarly, each of the plurality of second reference points that form the separation interval D is arranged on the reference straight line R3 starting from the start position P1 while maintaining the distance between adjacent second reference points.

[0047] Next, the correction unit 35 corrects the positions of the points included in the first three-dimensional point cloud and the positions of the points included in the second three-dimensional point cloud based on the reference straight line R3 (step S107). FIGS. 8(A) and 8(B) are diagrams for explaining the process of correcting the position of the first three-dimensional point cloud. FIG. 8(A) shows the first three-dimensional point cloud G1 and the first reference line R1 before the position is corrected.

[0048] For each of the plurality of first reference points that form the separation interval D of the first reference line R1, the correction unit 35 obtains the position difference H2 (see FIG. 7) between this first reference point and the point on the reference line R3 corresponding thereto, and uses this position difference H2 to correct the positions of the points included in the first three-dimensional point group corrected by the first correction matrix and associated with this first reference point. Also, for each of the plurality of second reference points that form the separation interval D of the second reference line R2, the correction unit 35 obtains the position difference H3 (see FIG. 7) between this second reference point and the point on the reference line R3 corresponding thereto, and uses the position difference H3 to correct the positions of the points included in the second three-dimensional point group associated with the second reference point 3.

[0049] The matrix for converting a first reference point to a point on the corresponding reference line R3 (hereinafter also referred to as the second correction matrix) is represented by a combination of a translation matrix representing translation and a rotation matrix representing rotation. The position correction using the position difference H2 can be represented by this second correction matrix. The correction unit 35 uses the second correction matrix to correct the positions of the points included in the first three-dimensional point group corrected by the first correction matrix and associated with each of the plurality of first reference points that form the separation interval D of the first reference line R1. When the first reference line R1 is set using a plurality of points of the first three-dimensional point group, the positions of the points of the first three-dimensional point group forming the first reference line R1 are also corrected using the second correction matrix.

[0050] The matrix for converting a second reference point to a point on the corresponding reference line R3 (hereinafter also referred to as the third correction matrix) is represented by a combination of a translation matrix representing translation and a rotation matrix representing rotation. The position correction using the position difference H3 can be represented by this third correction matrix. The correction unit 35 uses the third correction matrix to correct the positions of the points included in the second three-dimensional point group associated with each of the plurality of second reference points that form the separation interval D of the second reference line R2.

[0051] FIG. 8(B) shows the first three-dimensional point group G1 and the reference straight line R3 whose positions are corrected by the second correction matrix. The position of the first three-dimensional point group G1 whose position is corrected by the second correction matrix can be represented, for example, using a rectangular coordinate system with the reference straight line R3 in the y-axis direction and the starting position P1 as the origin. As shown in FIG. 8(B), the first three-dimensional point group G1 is linearly arranged around the reference straight line R3. Although not shown, the second three-dimensional point group whose position is corrected by the third correction matrix is also linearly arranged around the reference straight line R3.

[0052] Next, the correction unit 35 corrects the position of the first three-dimensional point group along the reference straight line R3 (step S108). The correction unit 35 generates a first projection image obtained by projecting the first three-dimensional point group whose position is corrected by the second correction matrix onto a projection plane including the reference straight line R3. FIG. 9(A) is a diagram showing the first projection image 900. The pixels of the first projection image 900 may have luminances represented by 0 to 255, with the luminance of the pixels where points exist being 255 and the luminance of the pixels where no points exist being 0. This description also applies to the second projection image described later.

[0053] Also, the correction unit 35 generates a second projection image 901 obtained by projecting the second three-dimensional point group whose position is corrected by the third correction matrix onto the above-mentioned projection plane including the reference straight line R3. FIG. 9(B) is a diagram showing the second projection image 901. The first projection image 900 and the second projection image 901 are formed by projecting the three-dimensional point groups onto the same projection plane. However, FIG. 9(A) shows an image in which only the first three-dimensional point group is projected, and FIG. 9(B) shows an image in which only the second three-dimensional point group is projected.

[0054] Then, the correction unit 35 selects a first straight line pattern that extends in a direction orthogonal to the reference straight line R3 and has a length equal to or greater than a predetermined second reference distance from the first projection image 900. Here, it is preferable that the correction unit 35 selects, from the first projection image 900, a first straight line pattern that is located within a predetermined distance from the reference straight line R3, extends in a direction orthogonal to the reference straight line R3, and has a length equal to or greater than a predetermined second reference distance. The second reference distance can be set to 0.5 m to 5 m. The predetermined distance from the reference straight line R3 can be set to 1 m to 5 m. FIG. 10(A) is a diagram showing a plurality of first straight line patterns E1 to E9.

[0055] Then, the correction unit 35 detects a second straight line pattern having the same shape as the first straight line pattern from the second projection image. In the example shown in FIG. 10(A), for each of the first straight line patterns E1 to E9, the correction unit 35 detects, from the second projection image 901, a second straight line pattern having the same shape as the first straight line pattern E1 to E9 from a region within a predetermined range with respect to the first straight line patterns E1 to E9. The pixels representing the first straight line pattern and the second straight line pattern described above can be detected from the projection image using, for example, a Sobel filter. FIG. 10(B) is a diagram showing a plurality of second straight line patterns F1 to F9. In the examples shown in FIGS. 10(A) and 10(B), the second straight line pattern F1 is detected from the second projection image 901 as the straight line pattern having the same shape as the first straight line pattern E1. Similarly, the second straight line patterns F2 to F9 are detected from the second projection image 901 as the straight line patterns having the same shape as the first straight line patterns E2 to E9.

[0056] Then, the correction unit 35 obtains the difference H4 in the position in the direction of the reference straight line R3 between each of the second straight line patterns F1 to F9 and the corresponding first straight line patterns E1 to E9, and uses this difference H4 in position to correct the position of the point on the reference straight line R3 corresponding to the position of the first straight line patterns E1 to E9, and the position of the point included in the first three-dimensional point group associated with the first reference point corresponding to the point on the reference straight line R3.

[0057] The position correction using the position difference H4 can be represented by a fourth correction matrix. The fourth correction matrix is represented by a translation matrix representing translation. The correction unit 35 corrects the positions of the points on the reference straight line R3 corresponding to the positions of the first straight line patterns E1 to E9 and the positions of the points included in the first three-dimensional point group associated with the first reference point corresponding to the points on the reference straight line R3.

[0058] When the point on the reference straight line R3 corresponding to the position of the first straight line pattern and the corresponding first reference point are not associated with the points included in the first three-dimensional point group, the fourth correction matrix for the first reference point associated with the points included in the first three-dimensional point group is based on the fourth correction matrix for the position of the point on the reference straight line R3 corresponding to the position of one or two first straight line patterns adjacent to the point on the reference straight line R3 corresponding to this first reference point, and is obtained by linear interpolation or curve interpolation.

[0059] Next, the correction unit 35 performs interpolation correction on the positions of the points on the reference straight line R3 located between two adjacent first straight line patterns among the first straight line patterns E1 to E9, and the positions of the points included in the first three-dimensional point group associated with the first reference points corresponding to the points on the reference straight line R3 (step S109). As the interpolation correction, linear interpolation or curve interpolation can be used. For the points on the reference straight line R3 where only one of the adjacent first straight line patterns E1 to E9 is adjacent to this point, linear interpolation or curve interpolation is used by extrapolation. By this interpolation correction, for example, the position of the point on the reference straight line R3 located between the first straight line pattern E1 and the first straight line pattern E2, and the position of the point included in the first three-dimensional point group associated with the first reference point corresponding to the point on the reference straight line R3 are interpolated and corrected. Similarly, the positions of the points on the reference straight line R3 located between the first straight line pattern E2 and the first straight line pattern E3, between the first straight line pattern E3 and the first straight line pattern E4, between the first straight line pattern E4 and the first straight line pattern E5, between the first straight line pattern E5 and the first straight line pattern E6, between the first straight line pattern E6 and the first straight line pattern E7, between the first straight line pattern E7 and the first straight line pattern E8, and between the first straight line pattern E8 and the first straight line pattern E9, and the positions of the points included in the first three-dimensional point group associated with the first reference points corresponding to the points on the reference straight line R3 are interpolated and corrected.

[0060] Next, the correction unit 35 rotates the position of the first three-dimensional point group about the reference straight line R3 as an axis to correct the angle (step S1l0). The correction unit 35 generates a first cross-sectional image representing the first three-dimensional point group whose position is corrected by the fourth correction matrix, including the points on the reference straight line R3 whose position is corrected by the fourth correction matrix and included in the cross-section orthogonal to the reference straight line R3. FIG. 11(A) is a diagram showing the first cross-sectional image 1100.

[0061] Further, the correction unit 35 generates a second cross-sectional image representing a second three-dimensional point group whose position is corrected by a third correction matrix and is included in the above cross-section. FIG. 11(B) is a diagram showing the second cross-sectional image 1101. The first cross-sectional image 1100 and the second cross-sectional image 1101 represent the same cross-section orthogonal to the reference line R3. In FIG. 11(A), an image showing only the first three-dimensional point group is shown, and in FIG. 11(B), an image showing only the second three-dimensional point group is shown. The pixels of the first cross-sectional image 1100 and the second cross-sectional image 1101 may have luminances represented by 0 to 255, with the luminance of the pixel where a point exists being 255 and the luminance of the pixel where no point exists being 0.

[0062] Then, the correction unit 35 selects a third straight line pattern extending in a direction orthogonal to the reference line R3 and having a length equal to or greater than a predetermined third reference distance from the first cross-sectional image 1100. Here, it is preferable that the correction unit 35 selects, from the first cross-sectional image 1100, a third straight line pattern that is located within a predetermined distance from the reference line R3, extends in a direction orthogonal to the reference line R3, and has a length equal to or greater than a predetermined third reference distance. The third reference distance can be set to 0.5 m to 5 m. The predetermined distance from the reference line R3 can be set to 1 m to 5 m.

[0063] FIG. 12(A) is a diagram showing the third straight line patterns E10 and E11. The third straight line pattern E10 and the third straight line pattern E11 are orthogonal to each other. The pixels representing the third straight line pattern and the fourth straight line pattern described later can be detected from the cross-sectional image using, for example, a Sobel filter.

[0064] Then, the correction unit 35 projects the third straight line pattern onto the second cross-sectional image, rotates the third straight line pattern about the reference straight line R3, and obtains the rotation angle when the fourth straight line pattern in the second cross-sectional image that matches the shape of the third straight line pattern is detected. Here, as the second cross-sectional image onto which the third straight line pattern is projected, for example, a cross-sectional image in which pixels representing edges are extracted using a Sobel filter may be used. FIG. 12(B) is a diagram showing the fourth straight line patterns F10 and F11. In the example shown in FIGS. 12(A) and 12(B), as the straight line pattern that matches the shape of the third straight line pattern E10, the fourth straight line pattern F10 is detected from the second projection image 901, and as the straight line pattern that matches the shape of the third straight line pattern E11, the fourth straight line pattern F11 is detected from the second projection image 901. In the example shown in FIGS. 12(A) and 12(B), two third straight line patterns and two corresponding fourth straight line patterns are detected, but only one third straight line pattern and one corresponding fourth straight line pattern may be detected.

[0065] Then, the correction unit 35 uses the obtained rotation angle to correct the angle around the reference straight line R3 of the points included in the first three-dimensional point group associated with the first reference point corresponding to the point on the reference straight line R3 included in the first cross-sectional image 1100. As in the example shown in FIGS. 12(A) and 12(B), when two third straight line patterns and two corresponding fourth straight line patterns are detected, the average value of the two rotation angles may be used for correction.

[0066] The correction of the position using the rotation angle can be represented by a fifth correction matrix. The fifth correction matrix is represented by a rotation matrix representing rotation. The correction unit 35 uses the fifth correction matrix to correct the angle around the reference straight line R3 of the points included in the first three-dimensional point group associated with the first reference point corresponding to the point on the reference straight line R3 included in the first cross-sectional image 1100. For each of the plurality of first reference points on the first reference line R1, the correction unit 35 obtains the fifth correction matrix and uses this fifth correction matrix to correct the angle around the reference straight line R3 of the points included in the first three-dimensional point group associated with the first reference point.

[0067] Next, the correction unit 35 performs a correction to return the position of the first 3D point group whose position has been corrected using the fifth correction matrix to the relationship between the first reference point and the first reference line (step S111). The correction unit 35 corrects the positions of the points included in the first 3D point group associated with the first reference point whose position has been corrected using the fifth correction matrix, using the difference H2 in position between the first reference point and the point on the reference line R3 corresponding to this first reference point. Specifically, the correction unit 35 corrects the positions of the points included in the first 3D point group associated with the first reference point whose position has been corrected using the fifth correction matrix, using the sixth correction matrix representing the inverse matrix of the second correction matrix.

[0068] FIG. 13(A) shows a diagram in which the first 3D point group whose position has been corrected is superimposed on the second 3D point group, and FIG. 13(B) shows a diagram in which the first 3D point group before correction is superimposed on the second 3D point group. As shown in FIG. 13(B), among the points included in the first 3D point group before correction, the points representing the same travel route and the surrounding environment as the second 3D point group are displaced from the second 3D point group. On the other hand, as shown in FIG. 13(A), due to the above-described correction, among the points included in the first 3D point group, the points representing the same travel route and the surrounding environment as the second 3D point group are at the same position.

[0069] According to the position information processing apparatus of the present embodiment described above, the 3D point group can be corrected so that two separately measured 3D point groups can be compared. Specifically, since the first 3D point group is converted into the relationship with the reference line, the position of the first 3D point group can be made comparable with the second 3D point group by using the correction of the position along the reference line of the first 3D point group and the correction of the angle with the reference line of the reference line of the first 3D point group as the rotation axis. According to the position information processing apparatus of the present embodiment, the correction process can be speeded up and the accuracy can be improved.

[0070] By making it possible to compare two separately measured 3D point groups using the position information processing apparatus, the map database can be updated or the equipment can be maintained.

[0071] In the present invention, the position information processing apparatus and the position information processing method of the above-described embodiments can be appropriately changed as long as they do not depart from the gist of the present invention. Further, the technical scope of the present invention is not limited to those embodiments, but extends to the invention described in the claims and its equivalents.

[0072] For example, in the above-described embodiment, the position information processing apparatus further corrects the position along the reference line of the first three-dimensional point group and corrects the angle with the reference line of the reference line of the first three-dimensional point group as the rotation axis, using the first three-dimensional point group whose position is corrected by the second correction matrix and the second three-dimensional point group whose position is corrected by the third correction matrix. However, the correction of the position along the reference line of the first three-dimensional point group and the correction of the angle with the reference line of the reference line of the first three-dimensional point group as the rotation axis may be manually performed by the user.

[0073] In the above-described embodiment, the correction unit 35 corrects the angle of the first three-dimensional point group by rotating it around the reference line. However, when it is estimated that the difference in angles is small, this correction may not be performed. In this case, the correction unit 35 corrects the positions of the points included in the first three-dimensional point group associated with the first reference point whose position is corrected using the fourth correction matrix, using the sixth correction matrix.

Explanation of Reference Numerals

[0074] 10 Position information processing apparatus 21 Communication interface 22 User interface 23 Memory 24 Processor 25 Communication line 31 Reference line setting unit 32 Section determination unit 33 Association unit 34 Corresponding unit 35 Correction unit 36 Straight line generation unit

Claims

1. A first reference line representing a predetermined linear environment set for a first three-dimensional point cloud representing the positions of the surroundings of a first travel route of the first vehicle, which is collected by scanning a laser scanner mounted on the first vehicle, and a second three-dimensional point cloud representing the positions of the surroundings of a second travel route including at least a partially same route as the first travel route, which is collected by scanning a laser scanner mounted on a second vehicle. A start position at which the distance between the first reference line and a second reference line representing the predetermined linear environment corresponding to the first reference line starts to be separated by more than a predetermined first reference distance, and a section determination unit that determines a separation section in which the distance between the first reference line and the second reference line representing the predetermined linear environment corresponding to the first reference line is separated by more than the first reference distance, An association unit that associates each of a plurality of first reference points forming the separation section of the first reference line with a point included in the first three-dimensional point cloud, A correspondence unit that associates each of the plurality of first reference points forming the separation section of the first reference line with a second reference point forming the separation section of the second reference line, For each of the plurality of first reference points forming the separation section of the first reference line, a difference in position between the first reference point and the second reference point associated therewith is obtained, and using the difference in position, a first correction unit that corrects the position of a point included in the first three-dimensional point cloud associated with the first reference point, A straight line generation unit that arranges each of the plurality of first reference points forming the separation section of the first reference line to extend in a predetermined direction starting from the start position so that the distance between adjacent first reference points is maintained, thereby generating a reference straight line, and arranges each of the plurality of second reference points forming the separation section of the second reference line on the reference straight line starting from the start position so that the distance between adjacent second reference points is maintained, For each of the plurality of first reference points that form the separation section of the first reference line, determine the difference in position between the first reference point and the point on the reference line corresponding to the first reference point, and use the difference in position to correct the positions of the points included in the first three-dimensional point group associated with the first reference point corrected by the first correction unit. Further, for each of the plurality of second reference points that form the separation section of the second reference line, determine the difference in position between the second reference point and the point on the reference line corresponding to the second reference point, and use the difference in position to correct the positions of the points included in the second three-dimensional point group associated with the second reference point. A second correction unit; A position information processing apparatus, characterized by comprising the above. **Claim 2** The position information processing apparatus according to claim 1, further comprising a reference line setting unit that sets the first reference line using a plurality of points in the first three-dimensional point group and sets the second reference line using a plurality of points in the second three-dimensional point group. **Claim 3** The reference line setting unit sets the first reference line based on points having a reflection intensity of a laser scanner equal to or higher than a predetermined threshold among the first three-dimensional point group included in a predetermined region determined based on the position information representing the travel locus of the first vehicle, and sets the second reference line based on points having a reflection intensity of a laser scanner equal to or higher than a predetermined threshold among the second three-dimensional point group included in the predetermined region determined based on the position information representing the travel locus of the second vehicle. The position information processing apparatus according to claim 2. **Claim 4** The first vehicle and the second vehicle are railway vehicles, The reference line setting unit sets the first reference line based on points representing the track on which the first vehicle travels among the first three-dimensional point group, and sets the second reference line based on points representing the track on which the second vehicle travels among the second three-dimensional point group. The position information processing apparatus according to claim 2. **Claim 5** The associating unit associates, for each of the plurality of first reference points that form the separation section, the points of the first three-dimensional point group that include the first reference point and are included in a cross section orthogonal to the first reference line with the first reference point. The position information processing apparatus according to any one of claims 1 to 4. **Claim 6** The associating unit For each of the plurality of first reference points forming the separation section of the first reference line, a point included in the first three-dimensional point group, whose position was measured at the same time as the time when the first reference point was measured, is associated with the first reference point. The position information processing apparatus according to any one of claims 2 to 4.

7. The associating unit For each of the plurality of first reference points forming the separation section of the first reference line, the second reference point located at the position closest to the first reference point is associated with the first reference point. The position information processing apparatus according to any one of claims 1 to 6.

8. The associating unit For each of the plurality of first reference points forming the separation section, the ratio of the distance from the start position to the first reference point to the distance of the separation section on the first reference line, and the ratio of the distance from the start position to the second reference point to the distance of the separation section on the second reference line are made to match, and the second reference point is associated. The position information processing apparatus according to any one of claims 1 to 6.

9. Generate a first projection image obtained by projecting the first three-dimensional point group whose position has been corrected by the second correction unit onto a projection plane including the reference straight line, select a first straight line pattern extending in a direction orthogonal to the reference straight line and having a length equal to or greater than a predetermined second reference distance from the first projection image, Detect a second straight line pattern having the same shape as the first straight line pattern from a second projection image obtained by projecting the second three-dimensional point group whose position has been corrected by the second correction unit onto the projection plane, Obtain the difference in position between the second straight line pattern and the first straight line pattern, and use the difference in position to correct the position of a point on the reference straight line corresponding to the position of the first straight line pattern and the position of a point included in the first three-dimensional point group associated with the first reference point corresponding to the point on the reference straight line. The position information processing apparatus having a third correction unit according to any one of claims 1 to 8.

10. Generate a first cross-sectional image representing the first three-dimensional point group whose position has been corrected by the third correction unit, including the point on the reference straight line corrected by the third correction unit and included in a cross-section orthogonal to the reference straight line, Select a third straight line pattern extending in a direction orthogonal to the reference straight line and having a length equal to or greater than a predetermined third reference distance from the first cross-sectional image, Generate a second cross-sectional image representing the second three-dimensional point group whose position has been corrected by the second correction unit and included in the cross-section. Project the third straight-line pattern onto the second cross-sectional image, rotate the third straight-line pattern about the reference straight line, and determine the rotation angle when a fourth straight-line pattern in the second cross-sectional image that matches the shape of the third straight-line pattern is detected. Using the rotation angle, correct the angle around the reference straight line of the points included in the first three-dimensional point group associated with the first reference point corresponding to the point on the reference straight line included in the first cross-sectional image. The position information processing apparatus according to claim 9, comprising a fourth correction unit.

11. The position of the point included in the first three-dimensional point group associated with the first reference point, whose position is corrected by the fourth correction unit, is corrected using the difference in position between the first reference point and the point on the reference straight line corresponding to the first reference point. The position information processing apparatus according to claim 10, comprising a fifth correction unit.

12. A first reference line representing a predetermined linear environment set for a first three-dimensional point group representing the position of the environment around the first travel route of the first vehicle, collected by scanning a laser scanner mounted on the first vehicle, and a second reference line representing the position of the environment around the second travel route including at least a partially same route as the first travel route, collected by scanning a laser scanner mounted on the second vehicle. Determine a start position at which the distance between the second reference line representing the predetermined linear environment corresponding to the first reference line and the first reference line starts to be separated by more than a predetermined first reference distance, and determine a separation section in which the distance between the second reference line representing the predetermined linear environment corresponding to the first reference line and the first reference line is separated by more than the first reference distance. Associate each of the plurality of first reference points forming the separation section of the first reference line with a point included in the first three-dimensional point group. Associate each of the plurality of first reference points forming the separation section of the first reference line with a second reference point forming the separation section of the second reference line. For each of the plurality of first reference points forming the separation section of the first reference line, obtain the difference in position between the first reference point and the second reference point associated with the first reference point, and correct the position of the point included in the first three-dimensional point group associated with the first reference point using the difference in position. Each of the plurality of first reference points forming the separation section of the first reference line is arranged to extend in a predetermined direction starting from the start position so that the distance between adjacent first reference points is maintained, thereby generating a reference line. And each of the plurality of second reference points forming the separation section of the second reference line is arranged on the reference line starting from the start position so that the distance between adjacent second reference points is maintained. For each of the plurality of first reference points forming the separation section of the first reference line, the difference in position between the first reference point and the point on the reference line corresponding thereto is obtained, and using the difference in position, the positions of the points included in the first three-dimensional point group associated with the first reference point corrected by the correction are corrected. And for each of the plurality of second reference points forming the separation section of the second reference line, the difference in position between the second reference point and the point on the reference line corresponding thereto is obtained, and using the difference in position, the positions of the points included in the second three-dimensional point group associated with the second reference point are corrected. A position information processing method executed by a position information processing apparatus, characterized by the above.

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