Marker stand

Abstract

To eliminate ambiguity of the direction of a marker stand.SOLUTION: A marker stand 3 is used for determining the relative position and orientation of a local coordinate system 5R of a two-dimensional LiDAR5 as viewed from a local coordinate system 7R of a robot body 7. The marker stand 3 includes: a stand body 8; a marker 9 which is provided on the stand body 8 and can be imaged by an imaging camera 6; and a first leg 10 and a second leg 11 which are provided on the stand body 8 and can be measured in terms of distance by the two-dimensional LiDAR5. The first leg 10 and the second leg 11 have one fold symmetry in a plan view.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a marker stand.

Background Art

[0002] Patent Document 1 discloses an electronic calibration method for an in-vehicle camera that images the periphery of a vehicle. Specifically, a calibration target board is placed around the vehicle, and the in-vehicle camera is electronically calibrated based on the imaging data obtained by imaging the target board with the in-vehicle camera. At this time, it is necessary to position the target board with high precision with respect to the vehicle. Therefore, in Patent Document 1, an irradiation device having a laser light source for irradiating laser light is placed at a determined position with respect to the vehicle, the laser light is irradiated from the irradiation device toward the target board, and the target board is positioned so that the laser light is irradiated to a predetermined position of the target board.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, the inventor of the present invention has been considering the electronic calibration of an imaging device mounted on a robot body of an autonomous mobile robot. That is, when assembling the imaging device to the robot body, due to the shape error of the robot body or the imaging device and the assembly error that occurs when the imaging device is assembled to the robot body, there will inevitably be errors in the relative position and orientation of the local coordinate system of the imaging device as seen from the local coordinate system of the robot body. Among these errors, the orientation error in particular cannot be overlooked. For example, if the orientation error of the imaging device is 1 degree, an imaging object 10 meters away will be recognized as being displaced by approximately 17 centimeters in any of the up, down, left, or right directions, which will have various adverse effects on the autonomous movement control of the autonomous mobile robot.

[0005] As a method of avoiding the above-mentioned orientation error, it is possible to strictly manage the tolerances of the shape error and the assembly error. However, this method will increase the manufacturing cost of the autonomous mobile robot and also lead to a decrease in yield.

[0006] Therefore, while leaving the above-mentioned errors as they are, it is effective to measure the relative position and orientation of the local coordinate system of the imaging device as seen from the local coordinate system of the robot body with high precision, and perform electronic calibration of the imaging device using the measurement results.

[0007] As a method of measuring the relative position and orientation of the local coordinate system of the imaging device as seen from the local coordinate system of the robot body with high precision, the above-mentioned inventor has been considering the following method. That is, a marker stand provided with two upright cylinders is prepared on a stand body provided with markers, and the two cylinders are distance-measured with a LiDAR (Light Detection And Ranging) accurately positioned on the robot body to generate point cloud data, and the markers are imaged with the imaging device, and the relative position and orientation of the local coordinate system of the imaging device as seen from the local coordinate system of the robot body are measured with high precision using the point cloud data and the imaging data.

[0008] (1) Here, the relative position and orientation of the LiDAR's local coordinate system as seen from the local coordinate system of the robot body can be made known by the above-mentioned high-precision positioning. (2) The relative position and orientation of the cylinder's local coordinate system as seen from the LiDAR's local coordinate system can be obtained with high precision by distance measurement using the LiDAR. (3) The relative position and orientation of the marker's local coordinate system as seen from the cylinder's local coordinate system are known from actual measurement. (4) The relative position and orientation of the marker's local coordinate system as seen from the local coordinate system of the imaging device can be obtained with high precision by imaging using the imaging device. Then, the relative position and orientation of the imaging device's local coordinate system as seen from the local coordinate system of the robot body can be calculated by performing matrix operations on the relative positions and orientations in (1) to (4) above. And since the relative positions and orientations in (1) to (4) are obtained with high precision, the relative position and orientation of the imaging device's local coordinate system as seen from the local coordinate system of the robot body can also be calculated with high precision in the same way. Here, high precision typically means that the aforementioned position error is 1 centimeter or less and the aforementioned orientation error is 0.1 degree or less.

[0009] By the way, in the above (2), the reason for using two upright cylinders as the objects to be measured by LiDAR is that LiDAR has robustness in recognizing cylinders due to its characteristics. However, the above (2) had an unsolved problem. That is, when obtaining the relative position and orientation of the local coordinate system of the cylinder as seen from the local coordinate system of LiDAR using the point cloud data output from LiDAR, the two upright cylinders cannot be distinguished and identified. Therefore, when calculating the relative position of the local coordinate system of the cylinder as seen from the local coordinate system of LiDAR based on the point cloud data output from LiDAR, there will be two solutions in the calculation result. Specifically, based on only the above point cloud data, it is impossible to even identify whether the autonomous mobile robot is located in front of or behind the marker stand. In other words, there remained an unresolved ambiguity of 180 degrees in the orientation of the marker stand as seen from the autonomous mobile robot.

[0010] Therefore, an object of the present disclosure is to provide a technique for eliminating the ambiguity in the orientation of the marker stand.

Means for Solving the Problem

[0011] According to the viewpoint of the present disclosure, A marker stand, which is mounted on a mobile body main body with a LiDAR and a sensor, the relative position and orientation of the local coordinate system of the LiDAR as seen from the local coordinate system of the mobile body main body are known, and the relative position and orientation of the local coordinate system of the sensor as seen from the local coordinate system of the mobile body main body are unknown, and is used to obtain the relative position and orientation of the local coordinate system of the sensor as seen from the local coordinate system of the mobile body main body in the mobile body, including a stand main body, a marker provided on the stand main body and capable of being sensed by the sensor, and a plurality of ranging targets provided on the stand main body and capable of being ranged by the LiDAR, and the plurality of ranging targets have rotational symmetry of order 1 in plan view or are made of different materials from each other. ​ A marker stand is provided. The plurality of ranging targets includes two ranging targets, and the horizontal cross-sections of the two ranging targets may each be circular and have different diameters from each other. The plurality of ranging targets includes two ranging targets, and the horizontal cross-sections of the two ranging targets may have different shapes from each other. The plurality of ranging targets includes three or more ranging targets, and the three or more ranging targets may be arranged to be rotationally symmetric in plan view. The sensor may be an imaging camera. The LiDAR may be a two-dimensional LiDAR that emits laser light in a horizontal plane.

Advantages of the Invention

[0012] According to the present disclosure, the ambiguity in the orientation of the marker stand can be eliminated.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Modes for Carrying Out the Invention

[0014] (First Embodiment) Hereinafter, with reference to FIGS. 1 to 4, the first embodiment of the present disclosure will be described.

[0015] FIG. 1 shows a calibration system 1. As shown in FIG. 1, the calibration system 1 includes a mobile robot 2 and a marker stand 3.

[0016] The mobile robot 2 is an autonomous mobile robot and includes a robot body 7, a plurality of wheels 4, a two-dimensional LiDAR 5, and an imaging camera 6. The robot body 7 has a local coordinate system 7R.

[0017] The plurality of wheels 4 are rotatably provided on the marker stand 3. Some of the plurality of wheels 4 are drive wheels and the others are driven wheels.

[0018] The two-dimensional LiDAR 5 emits laser light radially in a horizontal plane to a measurement target, receives the reflected light, measures the distance to the measurement target, and generates point cloud data based on the measurement result and the emission direction of the laser light. The two-dimensional LiDAR 5 is typically arranged at a height of 30 centimeters from the floor surface. The two-dimensional LiDAR 5 is typically provided on the side surface of the robot body 7.

[0019] The above point cloud data is composed of a plurality of distance measurement point data. Each distance measurement point data includes the coordinate value and luminance value of the distance measurement point in the local coordinate system 5R of the two-dimensional LiDAR 5. The luminance value changes according to the distance from the two-dimensional LiDAR 5 to the measurement target and also changes according to the material of the measurement target. For example, if the distance from the two-dimensional LiDAR 5 to the measurement target is long, the luminance value becomes low accordingly. When the material of the measurement target is glass, the luminance value is lower than when the material of the measurement target is metal. However, each distance measurement point data may not include a luminance value. Note that the mobile robot 2 may be provided with a three-dimensional LiDAR instead of the two-dimensional LiDAR 5. The two-dimensional LiDAR 5 is a specific example of LiDAR.

[0020] Here, the LiDAR information 5X as the relative position and orientation of the local coordinate system 5R of the two-dimensional LiDAR 5 as seen from the local coordinate system 7R of the robot body 7 is known. That is, the LiDAR information 5X is managed with strict tolerances. For example, extremely narrow tolerances are set for the shape error of the two-dimensional LiDAR 5 and the assembly error when assembling the two-dimensional LiDAR 5 to the robot body 7. However, alternatively, the LiDAR information 5X may be measured with high precision at a cost by some method after assembly.

[0021] The imaging camera 6 images the external environment and generates imaging data. The imaging camera 6 is typically mounted on the upper surface of the robot body 7. The imaging camera 6 is a specific example of a sensor. The imaging camera 6 is a monocular camera, a stereo camera, or a depth camera. The mobile robot 2 may be provided with other sensors such as a three-dimensional LiDAR instead of the imaging camera 6. FIG. 1 shows the local coordinate system 6R of the imaging camera 6. The camera information 6X as the relative position and orientation of the local coordinate system 6R of the imaging camera 6 as seen from the local coordinate system 7R of the robot body 7 is unknown. That is, the camera information 6X is managed with loose tolerances. For example, slightly wider tolerances are set for the shape error of the imaging camera 6 and the assembly error when attaching the imaging camera 6 to the robot body 7. Thereby, the manufacturing cost of the mobile robot 2 is suppressed. In particular, when a large number of sensors other than the imaging camera 6 are assembled to the robot body 7, similar to the camera information 6X, it is desirable to manage the relative position and orientation of each sensor with respect to the robot body 7 with loose tolerances from the cost aspect.

[0022] The marker stand 3 includes a stand body 8, a marker 9, a first leg portion 10, and a second leg portion 11.

[0023] The marker 9 is provided on the side surface of the stand body 8. The marker 9 has a local coordinate system 9R.

[0024] The stand body 8 is supported by the first leg portion 10 and the second leg portion 11. The first leg portion 10 and the second leg portion 11 are a specific example of a plurality of distance measurement targets. Both the first leg portion 10 and the second leg portion 11 are in a vertically standing cylindrical shape and are arranged slightly apart from each other. Both the first leg portion 10 and the second leg portion 11 extend downward from the lower surface of the stand body 8. Both the first leg portion 10 and the second leg portion 11 have a height of 50 centimeters. Therefore, when the mobile robot 2 and the marker stand 3 are installed on the same floor surface, the first leg portion 10 and the second leg portion 11 can be distance-measured by the two-dimensional LiDAR 5.

[0025] In the present embodiment, the first leg portion 10 and the second leg portion 11 are made of the same material. That is, as an example, both the first leg portion 10 and the second leg portion 11 are resins. And as shown in FIG. 2, the diameter 10r of the first leg portion 10 is smaller than the diameter 11r of the second leg portion 11. Therefore, it is possible to easily determine which of the two arc point clouds that appear in the point cloud data generated by distance-measuring the first leg portion 10 and the second leg portion 11 by the two-dimensional LiDAR 5 corresponds to the first leg portion 10 and which corresponds to the second leg portion 11. Typically, based on the two arc point clouds, the respective arc radii are calculated, and the arc point cloud with the smaller arc radius corresponds to the first leg portion 10, and the arc point cloud with the larger arc radius corresponds to the second leg portion 11.

[0026] Returning to FIG. 1, the first leg portion 10 and the second leg portion 11 have a common local coordinate system 12R. The first marker information 9X, which is the relative position and orientation of the local coordinate system 9R of the marker 9 as seen from the local coordinate system 12R, is known with high precision by actual measurement. And the stand information 12X, which is the relative position and orientation of the local coordinate system 12R as seen from the local coordinate system 5R of the two-dimensional LiDAR 5, can be obtained with high precision based on the point cloud data output from the above-described two-dimensional LiDAR 5.

[0027] Also, according to the imaging data obtained by imaging the marker 9 with the imaging camera 6, the second marker information 9Y, which is the relative position and orientation of the local coordinate system 9R of the marker 9 as seen from the local coordinate system 6R of the imaging camera 6, can also be obtained with high precision.

[0028] Therefore, the camera information 6X indicating the relative position and orientation of the local coordinate system 6R of the imaging camera 6 as seen from the local coordinate system 7R of the robot body 7 can be easily obtained by matrix operations of the LiDAR information 5X, the stand information 12X, the first marker information 9X, and the second marker information 9Y.

[0029] Fig. 3 shows a functional block diagram of the mobile robot 2. The mobile robot 2 includes a CPU 2a (Central Processing Unit) as a central processing unit, a RAM 2b (Random Access Memory) that can be read and written freely, and a ROM 2c (Read Only Memory) that can only be read. Then, by reading and executing the control program stored in the ROM 2c, the control program causes hardware such as the CPU 2a to function as a map information storage unit 15, an autonomous movement control unit 16, and a calibration unit 17. The mobile robot 2 further includes the two-dimensional LiDAR 5 and the imaging camera 6 as described above.

[0030] The map information storage unit 15 stores map information of the service environment in which the mobile robot 2 provides services.

[0031] The autonomous movement control unit 16 controls the autonomous movement of the mobile robot 2 based on the point cloud data obtained from the two-dimensional LiDAR 5 and the imaging data obtained from the imaging camera 6 while referring to the map information stored in the map information storage unit 15. The imaging data obtained from the imaging camera 6 is electronically (logically) calibrated by the aforementioned camera information 6X.

[0032] The calibration unit 17 calculates and stores the aforementioned camera information 6X. Specifically, the calibration unit 17 receives the LiDAR information 5X from the operator and holds the LiDAR information 5X. The calibration unit 17 receives the first marker information 9X from the operator and holds the first marker information 9X. The calibration unit 17 controls the two-dimensional LiDAR 5 to obtain the point cloud data generated by the two-dimensional LiDAR 5 measuring the distances to the first leg 10 and the second leg 11, generates the stand information 12X based on the obtained point cloud data, and holds the generated stand information 12X. Similarly, the calibration unit 17 controls the imaging camera 6 to obtain the imaging data generated by the imaging camera 6 imaging the marker 9, generates the second marker information 9Y based on the obtained imaging data, and holds the generated second marker information 9Y. Then, the calibration unit 17 generates the camera information 6X based on the LiDAR information 5X, the stand information 12X, the first marker information 9X, and the second marker information 9Y, and holds the generated camera information 6X.

[0033] Next, with reference to FIG. 4, the control flow of the mobile robot 2 will be described.

[0034] First, the calibration unit 17 obtains the LiDAR information 5X according to the operator's input (S100).

[0035] Next, the calibration unit 17 obtains the first marker information 9X according to the operator's input (S110).

[0036] Next, the calibration unit 17 controls the two-dimensional LiDAR 5 to measure the distances to the first leg 10 and the second leg 11 with the two-dimensional LiDAR 5 (S120). As a result, the two-dimensional LiDAR 5 generates point cloud data, and the calibration unit 17 obtains the point cloud data from the two-dimensional LiDAR 5 (S130). Then, the calibration unit 17 generates the stand information 12X based on the point cloud data obtained from the two-dimensional LiDAR 5 (S140).

[0037] Next, the calibration unit 17 controls the imaging camera 6 to cause the imaging camera 6 to image the marker 9 (S150). As a result, the imaging camera 6 generates imaging data, and the calibration unit 17 acquires the imaging data from the imaging camera 6 (S160). Then, the calibration unit 17 generates second marker information 9Y based on the imaging data acquired from the imaging camera 6 (S170).

[0038] Next, the calibration unit 17 generates camera information 6X based on the LiDAR information 5X, the stand information 12X, the first marker information 9X, and the second marker information 9Y (S180).

[0039] Next, the calibration unit 17 determines whether the number of times the camera information 6X has been generated has reached 10 (S190). If the calibration unit 17 determines that the number of times the camera information 6X has been generated has reached 10 (S190: YES), the calibration unit 17 averages the camera information 6X for 10 times and holds the averaged camera information 6X as the camera information 6X (S200). On the other hand, if the calibration unit 17 determines that the number of times the camera information 6X has been generated has not reached 10 (S190: NO), the operator is instructed to move the marker stand 3 (S210). In response to this, the operator moves the marker stand 3 within a predetermined amount of movement and within a predetermined amount of rotation angle. The predetermined amount of movement is typically 15 centimeters. The predetermined amount of rotation angle is typically 10 degrees. In short, the operator moves the marker stand 3 slightly based on the movement instruction from the mobile robot 2. Then, the calibration unit 17 returns the process to step S120.

[0040] As described above, by alternately repeating the movement of the marker stand 3 and the calculation of the camera information 6X, various noises are added to each piece of camera information 6X according to the change in the relative positional relationship between the mobile robot 2 and the marker stand 3. By preparing a plurality of sets of camera information 6X with such various noises and finally averaging these pieces of camera information 6X, the accuracy of the camera information 6X can be further improved.

[0041] As described above, the first embodiment of the present disclosure has been described. The above embodiment has the following features.

[0042] In the mobile robot 2 (mobile body) in which the two-dimensional LiDAR 5 (LiDAR) and the imaging camera 6 (sensor) are mounted on the robot body 7 (mobile body main body), the relative position and orientation of the local coordinate system 5R of the two-dimensional LiDAR 5 as viewed from the local coordinate system 7R of the robot body 7 are known, and the relative position and orientation of the local coordinate system 6R of the imaging camera 6 as viewed from the local coordinate system 7R of the robot body 7 are unknown. The marker stand 3 is used to obtain the relative position and orientation of the local coordinate system 5R of the two-dimensional LiDAR 5 as viewed from the local coordinate system 7R of the robot body 7. The marker stand 3 includes a stand body 8, a marker 9 provided on the stand body 8 and capable of being imaged (sensed) by the imaging camera 6, and a first leg portion 10 and a second leg portion 11 (a plurality of distance measurement targets) provided on the stand body 8 and capable of being distance-measured by the two-dimensional LiDAR 5. The first leg portion 10 and the second leg portion 11 have rotational symmetry in a plan view. According to the above configuration, the ambiguity of the orientation of the marker stand 3 can be eliminated.

[0043] (Second Embodiment) Hereinafter, with reference to FIG. 5, the second embodiment of the present disclosure will be described. Hereinafter, the description will focus on the differences between the present embodiment and the first embodiment, and duplicate descriptions will be omitted.

[0044] For example, as shown in FIG. 2, in the first embodiment, it is assumed that the horizontal cross section of the first leg portion 10 and the horizontal cross section of the second leg portion 11 are of the same circular shape.

[0045] In contrast, in the present embodiment, as shown in FIG. 5, the horizontal cross-section of the first leg portion 10 and the horizontal cross-section of the second leg portion 11 have different shapes from each other. In the example of FIG. 5, the horizontal cross-section of the first leg portion 10 is circular, and the horizontal cross-section of the second leg portion 11 is polygonal, that is, pentagonal. According to the above configuration, while the plurality of distance measurement points p in the first leg portion 10 draw an arc, the plurality of distance measurement points p in the second leg portion 11 draw at least two straight lines. Therefore, by previously causing the calibration unit 17 to memorize the characteristics of the figures drawn by the plurality of distance measurement points p for each distance measurement target, the calibration unit 17 can easily determine which of the two distance measurement targets appearing in the point cloud data corresponds to the first leg portion 10 and which corresponds to the second leg portion 11. According to the above configuration, the ambiguity of the orientation of the marker stand 3 can be eliminated.

[0046] (Third Embodiment) Hereinafter, with reference to FIG. 6, the third embodiment of the present disclosure will be described. Hereinafter, the description will focus on the differences between the present embodiment and the above-described first embodiment, and duplicate descriptions will be omitted.

[0047] For example, as shown in FIG. 2, in the above-described first embodiment, it is assumed that the material of the first leg portion 10 and the material of the second leg portion 11 are the same. Therefore, the luminance values of the distance measurement point data corresponding to the first leg portion 10 and the luminance values of the distance measurement point data corresponding to the second leg portion 11 were generally the same.

[0048] In contrast, in the present embodiment, as shown in FIG. 6, the first leg portion 10 and the second leg portion 11 are made of different materials. In the example of FIG. 6, the first leg portion 10 is made of metal, and the second leg portion 11 is made of glass. According to the above configuration, the luminance value of the distance measurement point data corresponding to the first leg portion 10 is higher than the luminance value of the distance measurement point data corresponding to the second leg portion 11. Therefore, by previously storing the luminance value characteristics for each distance measurement target in the calibration unit 17, the calibration unit 17 can easily determine which of the two distance measurement targets appearing in the point cloud data corresponds to the first leg portion 10 and which corresponds to the second leg portion 11. According to the above configuration, the ambiguity of the orientation of the marker stand 3 can be eliminated.

[0049] (Fourth Embodiment) Hereinafter, with reference to FIG. 7, the fourth embodiment of the present disclosure will be described. Hereinafter, the description will focus on the differences between the present embodiment and the above-described first embodiment, and duplicate descriptions will be omitted.

[0050] For example, as shown in FIG. 2, in the above-described first embodiment, the marker stand 3 is provided with the first leg portion 10 and the second leg portion 11.

[0051] In contrast, in the present embodiment, as shown in FIG. 7, the marker stand 3 includes a columnar third leg portion 13 that stands upright in addition to the first leg portion 10 and the second leg portion 11. The horizontal cross-sections of the first leg portion 10, the second leg portion 11, and the third leg portion 13 all have the same diameter. And the first leg portion 10, the second leg portion 11, and the third leg portion 13 are arranged so as to have one-fold symmetry in plan view. In the present embodiment, a line segment L connecting the center 10c of the horizontal cross-section of the first leg portion 10, the center 11c of the horizontal cross-section of the second leg portion 11, and the center 13c of the horizontal cross-section of the third leg portion 13 forms a triangle T. However, the triangle T is not an equilateral triangle. This is because if the triangle T is an equilateral triangle, the first leg portion 10, the second leg portion 11, and the third leg portion 13 have three-fold symmetry in plan view. The triangle T may be an isosceles triangle, a right triangle, or a right isosceles triangle. According to the above configuration, the ambiguity of the orientation of the marker stand 3 can be eliminated.

[0052] (Fifth Embodiment) Hereinafter, with reference to FIG. 8, the fifth embodiment of the present disclosure will be described. Hereinafter, the description will focus on the differences between the present embodiment and the above-described fourth embodiment, and overlapping descriptions will be omitted.

[0053] In the above-described fourth embodiment, as shown in FIG. 7, a line segment L connecting the center 10c of the horizontal cross-section of the first leg portion 10, the center 11c of the horizontal cross-section of the second leg portion 11, and the center 13c of the horizontal cross-section of the third leg portion 13 forms a triangle T.

[0054] In contrast, in the present embodiment, as shown in FIG. 8, the center 10c of the horizontal cross-section of the first leg portion 10, the center 11c of the horizontal cross-section of the second leg portion 11, and the center 13c of the horizontal cross-section of the third leg portion 13 are arranged in a row on a straight line M in this order of description. And the distance D1 between the center 10c of the first leg portion 10 and the center 11c of the second leg portion 11 is shorter than the distance D2 between the center 11c of the second leg portion 11 and the center 13c of the third leg portion 13. According to the above configuration, since the first leg portion 10, the second leg portion 11, and the third leg portion 13 have one-fold symmetry, the ambiguity of the orientation of the marker stand 3 can be eliminated.

[0055] In the above example, the program can be stored using various types of non-transitory computer readable media and supplied to a computer. Non-transitory computer readable media include various types of tangible storage media. Examples of non-transitory computer readable media include magnetic recording media (such as flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (such as magneto-optical disks). Examples of non-transitory computer readable media further include CD-ROM (Read Only Memory), CD-R, CD-R / W, semiconductor memories (including mask ROM. Examples of non-transitory computer readable media further include PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM (random access memory)). Also, the program may be supplied to the computer by various types of transitory computer readable media. Examples of transitory computer readable media include electrical signals, optical signals, and electromagnetic waves. Transitory computer readable media can supply the program to the computer via wired communication channels such as electric wires and optical fibers, or wireless communication channels.

Explanation of Signs

[0056] 1 Calibration system 2 Mobile robot 3 Marker stand 4 Wheels 5 Two-dimensional LiDAR 5R Local coordinate system 5X LiDAR information 6 Imaging camera 6R Local coordinate system 6X Camera information 7 Robot body 7R Local coordinate system 8 Stand body 8X Stand Information 9 Markers 9R Local Coordinate System 9X First Marker Information 9Y Second Marker Information 10 First Leg 10r Diameter 11 Second Leg 11r Diameter 12R Local Coordinate System 15 Map Information Storage Unit 16 Autonomous Movement Control Unit 17 Calibration Unit

Claims

1. A marker stand used to obtain the relative position and orientation of the local coordinate system of a sensor as viewed from the local coordinate system of a mobile body main body, which is equipped with a LiDAR and the sensor on the mobile body main body, wherein the relative position and orientation of the local coordinate system of the LiDAR as viewed from the local coordinate system of the mobile body main body are known, and the relative position and orientation of the local coordinate system of the sensor as viewed from the local coordinate system of the mobile body main body are unknown, comprising: A stand body; A marker provided on the stand body and detectable by the sensor; A plurality of distance measurement targets provided on the stand body and measurable in distance by the LiDAR; Including; The plurality of distance measurement targets have one-fold symmetry in plan view as a whole; Marker stand.

2. The marker stand according to Claim 1, wherein: The plurality of distance measurement targets include two distance measurement targets; The horizontal cross-sections of the two distance measurement targets are both circular and have different diameters from each other; Marker stand.

3. The marker stand according to Claim 1, wherein: The plurality of distance measurement targets include two distance measurement targets; The horizontal cross-sections of the two distance measurement targets have different shapes from each other; Marker stand.

4. The marker stand according to Claim 1, wherein: The plurality of distance measurement targets include three or more distance measurement targets; The three or more distance measurement targets are arranged to be one-fold symmetric in plan view; Marker stand.

5. The marker stand according to any one of Claims 1 to 4, wherein: The sensor is an imaging camera; Marker stand.

6. The marker stand according to any one of Claims 1 to 4, wherein: The LiDAR is a two-dimensional LiDAR that emits laser light in a horizontal plane; Marker stand.

7. A marker stand used to obtain the relative position and orientation of the local coordinate system of a sensor as viewed from the local coordinate system of a mobile body main body, which is equipped with a LiDAR and the sensor on the mobile body main body, wherein the relative position and orientation of the local coordinate system of the LiDAR as viewed from the local coordinate system of the mobile body main body are known, and the relative position and orientation of the local coordinate system of the sensor as viewed from the local coordinate system of the mobile body main body are unknown, comprising: A stand body; A marker provided on the stand body and capable of being sensed by the sensor, A plurality of distance measurement targets provided on the stand body and capable of being distance-measured by the LiDAR, comprising, the plurality of distance measurement targets are made of different materials so that the luminance values of the point cloud data obtained by distance measurement with the LiDAR are different from each other among the plurality of distance measurement targets, Marker stand.

Images