Measuring system and measuring method

Abstract

To provide a measuring system that accurately measures the position of a robot in control of the robot.SOLUTION: A measuring system comprises a moving device that is movable relative to a robot including a movable part, and a measuring device 1 that is provided on the moving device and moves together with the moving device. The measuring device 1 includes: an irradiation unit that irradiates, with measuring light, a measurement target reflection element provided in the movable part of each of robots R1, R2, and irradiates, with reference measuring light, a reference reflection element arranged at a reference position in a space in which the moving device is arranged; and a measuring unit that, on the basis of reflected light of the measuring light from the measurement target reflection elements and reference reflected light of the reference measuring light from the reference reflection element, acquires position information or distance information related to the position of the measurement target reflection element provided on the movable part relative to the reference position in the space in which the robot is located.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a measurement system and a measurement method. [Background technology]

[0002] Machining and assembly processes are performed automatically using robots and machine tools. In these processes, in order to improve the accuracy of the machining and assembly, it is necessary to measure with high precision the position of the arm of the robot to be controlled and the position of the tip of the spindle of the machine tool. For example, there is known a device that measures the position of a predetermined part of a robot device using an external measuring device (Patent Document 1). In controlling a robot, it is required to measure the position of the robot with high accuracy. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2007 / 002319 Summary of the Invention

[0004] One aspect of the present invention is a measurement system comprising: a mobile device movable relative to a robot having a movable part; and a measuring device mounted on the mobile device and moving together with the mobile device, wherein the measuring device comprises an irradiation unit that irradiates measurement light onto a measured reflective element mounted on the movable part of the robot and irradiates reference measurement light onto a reference reflective element positioned at a reference position in a space in which the mobile device is disposed; and a measurement unit that acquires position information or distance information regarding the position of the measured reflective element mounted on the movable part relative to the reference position in the space in which the robot is located based on the reflected light of the measurement light from the measured reflective element and the reference reflected light of the reference measurement light from the reference reflective element.

[0005] One aspect of the present invention is a measurement method that includes moving a measuring device provided on a mobile device that is movable relative to a robot having a movable part together with the mobile device, measuring a measured reflective element provided on the movable part of the robot using measurement light from the measuring device, measuring a reference reflective element placed at a reference position in a space in which the mobile device is arranged using reference measurement light from the measuring device, and acquiring position information or distance information regarding the position of the measured reflective element provided on the movable part relative to the reference position in the space in which the robot is located based on the reflected light of the measurement light from the measured reflective element and the reference reflected light of the reference measurement light from the reference reflective element. [Brief explanation of the drawings]

[0006] [Figure 1] 1 is a diagram showing an example of how a mobile position measurement device according to a first embodiment moves within a factory. [Figure 2] 1 is a diagram showing an example of the appearance of a mobile position measurement device according to a first embodiment. [Figure 3] 1 is a diagram illustrating an example of the configuration of a position measurement device according to a first embodiment. [Figure 4] 1 is a diagram illustrating an example of a functional configuration of a position measurement device according to a first embodiment. [Figure 5] FIG. 4 is a diagram illustrating an example of a position measurement process according to the first embodiment. [Figure 6] FIG. 10 is a diagram illustrating an example of the configuration of a position measurement device according to a second embodiment. [Figure 7] FIG. 10 is a diagram illustrating an example of the functional configuration of a position measurement device according to a second embodiment. [Figure 8] FIG. 10 is a diagram illustrating an example of a position measurement process according to the second embodiment. [Figure 9] 10 shows an example of an imaging result of a second imaging unit according to the second embodiment. [Figure 10] FIG. 10 is a diagram illustrating an example of the functional configuration of a position measurement device according to a third embodiment. [Figure 11] FIG. 11 is a diagram illustrating an example of a position measurement process according to the third embodiment. [Figure 12] FIG. 10 is a diagram showing an example of how a mobile position measurement device according to a fourth embodiment measures a reference position. [Figure 13] FIG. 10 is a diagram illustrating an example of the functional configuration of a position measurement device according to a fourth embodiment. [Figure 14] FIG. 13 is a diagram illustrating an example of a position measurement process according to the fourth embodiment. [Figure 15] FIG. 13 is a diagram illustrating an example of a reference position information generation process according to the fourth embodiment. [Figure 16] FIG. 10 is a diagram showing an example of the operation of a mobile position measurement device according to the fifth embodiment. [Figure 17] 13A and 13B are diagrams showing an example of how a reflecting element according to a fifth embodiment is attached to and detached from a holder. [Figure 18] FIG. 13 is a diagram showing an example of how a mobile position measurement device according to a sixth embodiment controls a control system. [Figure 19] FIG. 13 is a diagram showing an example of how a mobile position measurement device according to a seventh embodiment controls a plurality of robots. [Figure 20] 13 is a diagram showing an example of how the position measurement device according to the eighth embodiment measures position information of an optical scanner. FIG. [Figure 21] FIG. 13 is a diagram showing an example of how the position measurement device according to the ninth embodiment measures position information in the process of assembling and processing the turbine. DETAILED DESCRIPTION OF THE INVENTION

[0007] (First embodiment) The first embodiment will be described in detail below with reference to the drawings. FIG. 1 is a diagram showing an example of a mobile position measurement device 1 according to this embodiment moving within a factory. The mobile position measurement device 1 can move freely within the factory. The mobile position measurement device 1 is a device that measures with high precision the position of a measurement target such as a machine tool or robot arranged within the factory, and the measurement results enable automatic calibration of the position of the machine tool or robot with high precision.

[0008] The mobile position measuring device 1 irradiates measurement light onto a reflecting element 4 arranged on a movable part of a measurement target and receives the reflected light. The mobile position measuring device 1 measures position information based on the light reception result. The position information is information indicating the position of the reflecting element 4 relative to a reference position. The reference position is a predetermined position in space where the reflecting element 4 is arranged.

[0009] The position information is represented by coordinates of a coordinate system (referred to as a reference coordinate system) in the space in which the reflecting element 4 is disposed. The position information is represented, for example, by Cartesian coordinates (X, Y, Z) shown in FIG. 1. A set of coordinates X, Y, and Z indicates a position in the Cartesian coordinates (X, Y, Z). The coordinates X, Y, and Z may also be referred to as the distance in the X direction, the distance in the Y direction, and the distance in the Z direction, respectively. In the Cartesian coordinates shown in FIG. 1, the angular component in the rotation direction around the X axis, the angular component in the rotation direction around the Y axis, and the angular component in the rotation direction around the Z axis may also be referred to as information about the position. Furthermore, when a position is represented by spherical coordinates, the angular components of the spherical coordinates may also be referred to as information about the position. Furthermore, when a position is represented by cylindrical coordinates, the angular components of the cylindrical coordinates may also be referred to as information about the position. Furthermore, FIG. 1 also illustrates an example of a coordinate system around the mobile position measurement device 1.

[0010] The mobile position measuring device 1 transmits the measured position information to the control system of the machine tool or robot. The reference position and coordinate system are shared in advance between the mobile position measuring device 1 and the control system. The control system can obtain the position of the machine tool or robot based on the position information received from the mobile position measuring device 1, allowing the machine tool or robot to be calibrated with high precision.

[0011] As described above, the mobile position measuring device 1 measures the position of the reflecting element 4 arranged in a predetermined portion, such as a movable part, of a part constituting a measurement target such as a machine tool or a robot. Therefore, the position of the measurement target is the position of a predetermined portion of the part constituting the measurement target. The predetermined portion is determined in advance with respect to the entire part constituting the measurement target. Therefore, the control system can obtain the position of the predetermined portion of the part constituting the measurement target based on the position information received from the mobile position measuring device 1, and calibrate the measurement target with high accuracy based on the position of the predetermined portion. Note that the predetermined portion of the part constituting the measurement target may be a part whose position in a coordinate system changes, in other words, a moving part.

[0012] The control system calculates a correction value for automatic calibration based on the position of the predetermined part. The control system controls the controlled object based on the calculated correction value. In other words, the control system calculates the correction value for automatic calibration based on the measurement result by the mobile position measurement device 1, and performs control based on the calculated correction value. In addition, the calculation of correction values ​​for automatic calibration based on the measurement results by the mobile position measuring device 1 and the control based on the calculation results of the correction values ​​may be performed by a host computer that controls the mobile position measuring device 1 and the measurement object such as a robot or machine tool.

[0013] The mobile position measurement device 1 irradiates a measuring light onto a reflecting element 4 arranged on a movable part of a measurement target and receives the reflected light. First, the mobile position measurement device 1 calculates distance information based on the light reception result. The distance information is information indicating the distance from the mobile position measurement device 1 to the reflecting element 4.

[0014] The mobile position measuring device 1 calculates direction information based on the irradiation direction of the measurement light. The direction information is information indicating the direction of the reflecting element 4 relative to a reference direction. The reference direction is, for example, the direction of the reference position as viewed from the mobile position measuring device 1. The direction information is represented by a pair of a latitude angle and a longitude angle (i.e., angle components of spherical coordinates).

[0015] Based on the calculated distance information and direction information, the mobile position measurement device 1 calculates the relative position of the reflecting element 4 with respect to the mobile position measurement device 1. Based on the position of the mobile position measurement device 1 with respect to the reference position and the position of the reflecting element 4 with respect to the mobile position measurement device 1, the mobile position measurement device 1 calculates the position of the reflecting element 4 with respect to the reference position (i.e., the position of the reflecting element 4 in the reference coordinate system) as position information.

[0016] The position of the mobile position measuring device 1 relative to the reference position is, in other words, the position of the mobile position measuring device 1 in a coordinate system set in the space in which the reflecting element 4 is disposed. In this embodiment, the position of the mobile position measuring device 1 relative to the reference position may be acquired in advance before measurement is started, after measurement is started (during measurement), or after measurement is completed (after measurement). The position of the mobile position measuring device 1 relative to the reference position is acquired, for example, from a control system. The position may also be measured by the mobile position measuring device 1 itself. A method for measuring the position of the mobile position measuring device 1 relative to the reference position (calibration of the origin) will be described in the following embodiments.

[0017] In this embodiment, the positional relationship between the mobile position measurement device 1 and the reference position is assumed to remain unchanged. Alternatively, in this embodiment, even if the positional relationship between the mobile position measurement device 1 and the reference position changes, the measurement result is not corrected. Cases in which the positional relationship between the mobile position measurement device 1 and the reference position changes will be described in subsequent embodiments.

[0018] The position information may be represented by spherical coordinates, cylindrical coordinates, or other orthogonal coordinate systems. An orthogonal coordinate system is a general term for coordinate systems in which unit vectors are orthogonal to each other. Position is a physical quantity that indicates where an object is located in space. Distance is a physical quantity that indicates the length measured between two points in space. Distance can be, for example, the Euclidean distance.

[0019] 2 is a diagram showing an example of the appearance of the mobile position measurement device 1 according to this embodiment. The mobile position measurement device 1 includes a position measurement device 2 and a mobile device 3. For ease of explanation, Figures 2, 3, and 6 show an XYZ Cartesian coordinate system, which is a three-dimensional Cartesian coordinate system. In this XYZ Cartesian coordinate system, the Z axis faces vertically upward. In the following explanation, the direction parallel to the Z axis is also referred to as the up-down direction. The direction of the Z axis is also referred to as the upward direction. The direction opposite to the Z axis is also referred to as the downward direction. The positive side of the Z axis is also referred to as the upper side, and the negative side of the Z axis is also referred to as the lower side. The direction parallel to the X axis is also referred to as the depth direction. The positive side of the X axis is also referred to as the front side, and the negative side of the X axis is also referred to as the back side. The direction parallel to the Y axis is also referred to as the left-right direction. The positive side of the Y axis is also referred to as the right side, and the negative side of the Y axis is also referred to as the left side.

[0020] The position measuring device 2 is placed on a moving device 3. The moving device 3 is movable. As a result, the position measuring device 2 is transported by the moving device 3. The moving device 3 is equipped with wheels, caterpillar tracks, or the like, and moves automatically. As a result, the moving device 3 can move freely within a factory. One example of the moving device 3 is an automatic guided vehicle (AGV, Autonomous Mobile Robot: AMR). Note that AGVs and AMRs are also called automatic guided robots.

[0021] The moving device 3 may be a transport machine other than an AGV as long as it can move while carrying the position measuring device 2. The moving device 3 may also be configured to move within a predetermined range or course within a factory. For example, the moving device 3 may move along rails or the like provided within the factory. Furthermore, the position measuring device 2 may be detached from the moving device 3 and placed on the floor or the like for use as a standalone device.

[0022] Next, we will explain the configuration of the position measurement device 2. Fig. 3 is a diagram showing an example of the configuration of the position measurement device 2 according to this embodiment. The position measurement device 2 includes a housing 10, an optical comb interferometer 11, a four-segment position sensitive detector (PSD) 12, a coaxial camera 13, a beam steering mirror 14, a pointing mirror assembly (PMA) 15, a first half mirror 16, and a second half mirror 17.

[0023] The housing 10 is a component for installing the main body of the position measurement device 2 on an installation target. When the position measurement device 2 is installed on an installation target, the housing 10 is positioned on the installation target. In this embodiment, the installation target is the mobile device 3. In this embodiment, the housing 10 is placed on the mobile device 3, and the position measurement device 2 is transported by the mobile device 3. The installation target may also be a factory floor, etc. The housing 10 fixes the position measurement device 2 to the installation target by, for example, its own weight. The housing 10 may also include a mechanism for fixing the position measurement device 2 to the installation target.

[0024] The housing 10 also contains the various components of the position measuring device 2. The housing 10 is fitted with the various components of the position measuring device 2. A beam steering mirror 14 and a PMA 15 are attached to the outside of the housing 10. The housing 10 also contains an optical comb interferometer 11, a four-segment PSD 12, a coaxial camera 13, a first half mirror 16, and a second half mirror 17. The housing 10 also has a space inside for the propagation of measurement light and reflected light.

[0025] The optical comb interferometer 11 measures the distance from itself to the measurement object. The optical comb interferometer 11 includes an optical comb light source. The optical comb light source is a light source capable of generating pulsed light containing frequency components equally spaced on the frequency axis (hereinafter referred to as an "optical frequency comb"). In this case, the optical comb light source emits pulsed light containing frequency components equally spaced on the frequency axis as measurement light. The optical comb interferometer 11 irradiates the optical frequency comb as measurement light onto a reflecting element 4 arranged on the measurement object. The optical comb interferometer 11 receives reflected light generated when the optical frequency comb is reflected by the reflecting element 4.

[0026] In this embodiment, the optical comb interferometer 11 includes a single measurement light source (i.e., an optical comb light source). The optical comb interferometer 11 may include multiple measurement light sources, for example, a first measurement light source and a second measurement light source. The multiple measurement light sources each emit multiple measurement light beams that are phase-synchronized and coherent with each other. For example, the multiple measurement light sources may have different oscillation frequencies. Therefore, the multiple measurement light beams emitted by the multiple measurement light sources each have different pulse frequencies (for example, the number of pulsed light beams per unit time, which is the reciprocal of the emission period of the pulsed light beam). As an example, the first measurement light source may emit a first measurement light beam with a pulse frequency of 25 GHz, and the second measurement light source may emit a second measurement light beam with a pulse frequency of 25 GHz+α (for example, +100 kHz).

[0027] In distance measurement using the optical comb interferometer 11, the distance from the optical comb interferometer 11 to the reflecting element 4 is measured based on the position where interference fringes occur between different pulses of the optical frequency comb. The optical comb interferometer 11 can measure the distance with an accuracy on the order of submicrometers, for example.

[0028] The optical comb interferometer 11 includes an irradiation unit, a light receiving unit, and a signal processing unit. The irradiation unit includes an optical comb light source, a frequency control unit, etc. The irradiation unit irradiates the measurement object with pulsed light generated by the optical comb light source as measurement light. The irradiation unit also branches a portion of the pulsed light generated by the optical comb light source and irradiates it as reference light on a reference plane within the optical comb interferometer 11. The light receiving unit includes a photodetector. The photodetector detects interference light between the reflected light and the reference light irradiated on the reference plane. When the detection result from the photodetector is input, the signal processing unit calculates the distance from the optical comb interferometer 11 to the reflecting element 4 based on the generation position of the pulsed light that creates the interference light between the reflected light and the reference light.

[0029] Here, the principle by which the optical comb interferometer 11 calculates the distance from the optical comb interferometer 11 to the reflecting element 4 will be described in more detail. The optical comb interferometer 11 includes two optical comb light sources, a first optical comb light source and a second optical comb light source, and two optical detectors, a first optical detector and a second optical detector.

[0030] The first optical frequency comb source generates a first measurement light, which is pulsed light having a first pulse frequency, as the measurement light. The second optical frequency comb source generates a second measurement light, which is pulsed light having a second pulse frequency, as the measurement light. The first pulse frequency and the second pulse frequency are different from each other.

[0031] When the first measurement light is emitted from the first optical frequency comb source, it is not irradiated onto the measurement object (i.e., the reflecting element 4) but is reflected by the optical system in the first optical frequency comb source and then enters the first optical detector as the first reflected light. On the other hand, the second measurement light is irradiated onto the measurement object (i.e., the reflecting element 4) from the second optical frequency comb source and reflected by the measurement object, and then enters the second optical detector as the second reflected light.

[0032] A part of the first measurement light is split and irradiated as a first reference light onto a reference surface in the optical comb interferometer 11, and then incident on the second photodetector. On the other hand, a part of the second measurement light is split and irradiated as a second reference light onto a reference surface in the optical comb interferometer 11, and then incident on the first photodetector.

[0033] Since the pulse frequency of the first measurement light is different from the pulse frequency of the second measurement light, the pulse frequency of the first reflected light is different from the pulse frequency of the second reference light, and therefore, the interference light between the first reflected light and the second reference light is an interference light in which the pulse light appears in synchronization with the timing when the pulse light constituting the first reflected light and the pulse light constituting the second reference light are simultaneously incident on the first photodetector.

[0034] Similarly, the pulse frequency of the first reference light is different from the pulse frequency of the second reflected light, and therefore the interference light between the first reference light and the second reflected light is an interference light in which the pulse light appears in synchronization with the timing at which the pulse light constituting the first reference light and the pulse light constituting the second reflected light are simultaneously incident on the second photodetector.

[0035] Here, the position (position on the time axis) of the pulsed light that creates the interference light detected by the second photodetector varies based on the positional relationship between the optical comb interferometer 11 and the object to be measured. This is because the interference light detected by the second photodetector is interference light between the second reflected light that travels toward the second photodetector via the object to be measured and the first reference light that travels toward the second photodetector without passing through the object to be measured. On the other hand, the position (position on the time axis) of the pulsed light that creates the interference light detected by the first photodetector does not vary based on the positional relationship between the optical comb interferometer 11 and the object to be measured.

[0036] Therefore, the time difference between the pulsed light that creates the interference light detected by the second photodetector and the pulsed light that creates the interference light detected by the first photodetector indirectly indicates the positional relationship between the optical comb interferometer 11 and the measurement object (typically, the distance between the optical comb interferometer 11 and the measurement object). Therefore, the optical comb interferometer 11 can calculate the distance from the optical comb interferometer 11 to the reflecting element 4 based on the time difference between the pulsed light that creates the interference light detected by the second photodetector and the pulsed light that creates the interference light detected by the first photodetector.

[0037] Here, the measurement light emitted by the optical comb interferometer 11 passes through a first half mirror 16 and a second half mirror 17, and is then reflected by a beam steering mirror 14 and irradiated onto the reflecting element 4. Here, the optical path of the measurement light irradiated onto the reflecting element 4 and the reflected light reflected by the reflecting element 4 share a portion in common.

[0038] The first half mirror 16 transmits the measurement light emitted from the optical comb interferometer 11. The first half mirror 16 also transmits a portion of the measurement light reflected by the reflecting element 4 toward the optical comb interferometer 11, and reflects the remaining portion toward the four-segment PSD 12.

[0039] The second half mirror 17 transmits the measurement light emitted from the optical comb interferometer 11. The second half mirror 17 also transmits a portion of the measurement light reflected by the reflecting element 4 toward the optical comb interferometer 11. The second half mirror 17 reflects the remaining portion toward the four-segment PSD 12. The second half mirror 17 also reflects the natural light reflected from the reflecting element 4 (or the light emitted by the LED) toward the coaxial camera 13, and the coaxial camera 13 captures the natural light reflected from the reflecting element 4 (or the light emitted by the LED).

[0040] The coaxial camera 13 captures an image of the reflective element 4, which is the object of measurement. The coaxial camera 13 captures an image of the reflective element 4 using natural light or artificial light such as light bulbs, fluorescent lamps, mercury lamps, LEDs, and strobes, reflected by the reflective element 4.

[0041] The coaxial camera 13 is used to track the position of the reflecting element 4. The coaxial camera 13 captures an image of the reflecting element 4, allowing the position measuring device 2 to roughly grasp the position of the reflecting element 4 and roughly adjust the direction of irradiation of the measurement light. Here, "the precision of measuring the position of the reflecting element 4 and adjusting the irradiation direction" means that the precision is lower than when a four-segment PSD 12 is used, as will be described later. Image A1 is an example of an image of reflecting element 4 captured by coaxial camera 13.

[0042] The term "coaxial" in "coaxial camera 13" may mean that part of the optical system of the coaxial camera 13 is common to part of the optical system of the optical comb interferometer 11 or / and part of the optical system of the four-segment PSD 12. For example, the term may mean that the optical system of the coaxial camera 13 and part of the optical system of the optical comb interferometer 11 or part of the optical system of the four-segment PSD 12 share the same optical components. Furthermore, the term "coaxial" in "coaxial camera 13" includes cases where part of the optical path of the coaxial camera 13 is closely positioned to part of the optical path of the optical comb interferometer 11 or / and part of the optical path of the four-segment PSD 12 (including cases where the optical paths are not completely identical). An example of optical paths that are not completely identical includes a case where the optical path of part of the coaxial camera 13 is closely positioned to but slightly offset from the optical paths of part of the optical comb interferometer 11 or / and part of the four-segment PSD 12. This case may be referred to as a slightly shifted relationship or a slightly tilted relationship.

[0043] The four-segment PSD 12 measures the position of the reflecting element 4 by detecting the reflected light from the reflecting element 4. The reflected light is measurement light irradiated by the optical comb interferometer 11 and reflected by the reflecting element 4. A portion of the reflected light is reflected by the first half mirror 16 and enters the four-segment PSD 12.

[0044] The four-segment PSD 12 includes, for example, photodiodes and resistors. The photodiodes are arranged in an array. In other words, the four-segment PSD 12 includes a photodiode array. The detection surface of the four-segment PSD 12 is divided into four. The four-segment PSD 12 measures the position of the spot light based on the amount of light of the spot light of reflected light detected on each of the four divided detection surfaces.

[0045] The four-segment PSD 12 is used to fine-tune the direction of irradiation of the measurement light after the position of the reflecting element 4 is roughly captured by the coaxial camera 13. Here, the accuracy of the position of the reflecting element 4 determined based on the image of the reflecting element 4 captured by the coaxial camera 13 is lower than the accuracy of the position of the reflecting element 4 measured by the four-segment PSD 12. Therefore, the accuracy of adjusting the irradiation direction of the measurement light based on the position of the reflecting element 4 determined based on the image of the reflecting element 4 captured by the coaxial camera 13 is lower than the accuracy of adjusting the irradiation direction of the measurement light based on the position of the reflecting element 4 measured by the four-segment PSD 12. The position measuring device 2 may include other position detectors instead of the four-segment PSD 12. Examples of other position detectors include a line sensor, a two-dimensional sensor (also called an area sensor), and a phase detection distance measuring device.

[0046] The beam steering mirror 14 reflects the measurement light emitted from the optical comb interferometer 11 toward the reflecting element 4. The beam steering mirror 14 also reflects the measurement light reflected from the reflecting element 4 toward the optical comb interferometer 11.

[0047] The PMA 15 moves (changes) the direction of the beam steering mirror 14. The PMA 15 includes, for example, a gimbal unit and a rotary encoder (not shown). The orientation of the beam steering mirror 14 is changed by driving the gimbal unit and changing the rotation angle of the gimbal unit. The gimbal unit can rotate the beam steering mirror 14 so that the direction of the beam steering mirror 14 can be changed in both the longitude and latitude directions. The rotary encoder measures the rotation angle of the gimbal unit.

[0048] The first imaging unit 23 includes the coaxial camera 13, and the meaning of "coaxial" in the "coaxial camera 13" is as described above. In the present embodiment, for example, the optical path of the reflected light used for imaging by the coaxial camera 13 is partially common to the optical path of the measurement light or reflected light used for distance measurement by the optical comb interferometer 11. In other words, at least a part of the optical path of the optical system for imaging by the first imaging unit 23 is common to at least a part of the optical path of the optical system for receiving light by the light receiving unit provided in the optical comb interferometer 11.

[0049] The imaging direction of the coaxial camera 13 is changed by changing the orientation of the beam steering mirror 14, which changes the direction of the measurement light emitted by the optical comb interferometer 11. In other words, the beam steering mirror 14 is used both to change the irradiation direction of the measurement light emitted by the optical comb interferometer 11 and to change the imaging direction of the coaxial camera 13.

[0050] The position measuring device 2 may include a camera outside the housing 10 instead of the coaxial camera 13. In this camera, the optical path of the reflected light used for imaging is not the same as the optical path of the measurement light or reflected light used for distance measurement by the optical comb interferometer 11. In this case, a drive mechanism is provided to change the imaging direction of the camera.

[0051] The reflective element 4 is placed on the object to be measured. The reflective element 4 is placed on a moving part of the object to be measured, such as a machine tool or a robot. One example of the reflective element 4 is a retroreflector. A retroreflector is an optical element that reflects a beam back in the incident direction, regardless of the position or direction from which the beam is incident on the retroreflector. In other words, a retroreflector has a retroreflection function.

[0052] In this embodiment, an example will be described in which the coaxial camera 13 captures an image of the reflecting element 4 and the position of the reflecting element 4 is identified, but this is not limiting. For example, the coaxial camera 13 may capture an image of a mark or the like placed on a predetermined part of the reflecting element 4 and identify the position of the reflecting element 4 by performing image analysis on the captured image.

[0053] For example, in image A1 of FIG. 3, multiple marks (mark M11, mark M12, mark M13, mark M14) are captured on the outer periphery of the reflecting element 4. The coaxial camera 13 may identify the position, or the position and posture, of the reflecting element 4 by capturing images of the multiple marks (mark M11, mark M12, mark M13, mark M14). The multiple marks are, for example, members that can be fitted to the outer periphery of the reflecting element 4. The multiple marks may be stickers. The multiple marks may be placed on the reflecting element 4 by painting the surface of the reflecting element 4.

[0054] 3 may be light-emitting diodes (LEDs). When the marks arranged at predetermined portions of the reflecting element 4 are LEDs, the accuracy of recognition by image analysis can be improved by flashing or lighting them up. In this case, the light used by the coaxial camera 13 for capturing images is emitted light instead of natural light reflected by the reflecting element 4. When a plurality of reflective elements 4 are provided, the reflective elements 4 may be distinguished from one another by varying the color or blinking cycle of the LED for each reflective element 4.

[0055] As another example of a method in which the coaxial camera 13 tracks (identifies) the position of the reflecting element 4, the coaxial camera 13 may capture an image of a feature point located at a predetermined position from the position of the reflecting element 4, and identify the position of the reflecting element 4 from the position of the feature point. The feature point may be, for example, a pattern in which a two-dimensional code is drawn. When the coaxial camera 13 captures an image of the feature point, it recognizes the feature point based on image recognition and identifies the position of the feature point. The coaxial camera 13 identifies the position of the reflecting element 4 based on the identified position. Furthermore, the coaxial camera 13 may identify the position of the reflecting element 4 by capturing an image of a known characteristic point on the exterior of a part of a robot arm or a part of a machine tool.

[0056] As described above, the position measurement device 2 is mounted on the moving device 3. Therefore, the irradiation unit and the light receiving unit of the optical comb interferometer 11 included in the position measurement device 2, the gimbal unit of the PMA 15, and the coaxial camera 13 are moved by the moving device 3. Furthermore, at least a part of the irradiation unit of the optical comb interferometer 11, at least a part of the light receiving unit of the optical comb interferometer 11, at least a part of the gimbal unit of the PMA 15, and at least a part of the coaxial camera 13 do not need to be mounted on the moving device 3. In other words, the moving device 3 may move at least one of the irradiation unit of the optical comb interferometer 11, the light receiving unit of the optical comb interferometer 11, the gimbal unit of the PMA 15, and the coaxial camera 13. Note that the irradiation unit and / or the light receiving unit of the optical comb interferometer 11 do not need to be moved by the moving device 3. In this case, the irradiating section and / or the light receiving section may be connected to the optical path of the measurement light and / or the reflected light within the housing 10 by an optical transmission member such as an optical fiber.

[0057] The irradiation unit of the optical comb interferometer 11 is provided on the moving device 3 and irradiates the reflecting element 4 with measurement light. The light receiving section of the optical comb interferometer 11 is provided on the moving device 3 and receives the measurement light reflected from the reflecting element 4. The signal processing unit included in the optical comb interferometer 11 acquires position information regarding the reflecting element 4 based on the light reception result by the light receiving unit included in the optical comb interferometer 11. The signal processing unit included in the optical comb interferometer 11 may also acquire distance information.

[0058] 4 is a diagram showing an example of the functional configuration of the position measurement device 2 according to this embodiment. The position measurement device 2 includes a position measurement unit 20, a control unit 22, a first imaging unit 23, a reflected light detection unit 24, a communication unit 25, and a moving device 27.

[0059] The position measurement unit 20 includes a distance measurement unit 200 , an irradiation direction movement unit 201 , an irradiation direction measurement unit 202 , and a position information acquisition unit 203 . The distance measurement unit 200 irradiates the reflecting element 4 with measurement light and receives the reflected light to measure the distance to the reflecting element. The distance measurement unit 200 includes an irradiation unit, a light receiving unit, and a signal processing unit. The irradiation unit irradiates the reflecting element arranged on the movable part of the measurement object with measurement light. The light receiving unit receives the reflected light. The signal processing unit processes the signal from the light receiving unit to obtain distance information to the reflecting element 4. The distance measurement unit 200 includes an optical comb interferometer 11. The irradiation unit includes an optical comb light source provided in the optical comb interferometer 11. The light receiving unit includes a light receiving unit provided in the optical comb interferometer 11. The signal processing unit includes a signal processing unit provided in the optical comb interferometer 11.

[0060] The irradiation direction moving unit 201 changes the irradiation direction of the measurement light. Changing the irradiation direction is also referred to as moving the irradiation direction. The irradiation direction moving unit 201 includes a gimbal unit included in the PMA 15. In this embodiment, as described above, the beam steering mirror 14 is used both to change the irradiation direction of the measurement light emitted by the optical comb interferometer 11 and to change the imaging direction of the coaxial camera 13. The irradiation direction moving unit 201 includes an imaging adjustment unit that adjusts the imaging direction of the first imaging unit 23. The imaging adjustment unit adjusts the imaging direction of the first imaging unit 23.

[0061] The irradiation direction measurement unit 202 measures the irradiation direction of the measurement light. The irradiation direction measurement unit 202 includes a rotary encoder that is included in the PMA 15 and measures the angle of the gimbal unit. The irradiation direction measurement unit 202 outputs the measurement result of the irradiation direction as direction information to the position information acquisition unit 203 of the distance measurement unit 200.

[0062] The position information acquisition unit 203 acquires the position (position information) of the reflecting element 4 in three-dimensional space from the distance (distance information) to the reflecting element 4 measured by the distance measurement unit 200 and the irradiation direction (direction information) of the measurement light measured by the irradiation direction measurement unit 202. The acquisition of the position information will be described in detail later.

[0063] The control unit 22 controls the other devices and components included in the position measurement device 2. The control unit 22 includes, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), and an FPGA (Field-Programmable Gate Array), and performs various calculations and information transmission and reception. The control unit 22 loads a program from the ROM and executes various controls in accordance with the loaded program.

[0064] The control unit 22 and each device and component included in the position measurement device 2 are connected by, for example, a signal line. The control unit 22 and each device and component included in the position measurement device 2 may communicate with each other by short-range wireless communication using electromagnetic waves such as light or radio waves. The control unit 22 executes various calculations and includes an imaging adjustment unit.

[0065] The first imaging unit 23 captures an image of the reflecting element 4. The first imaging unit 23 includes a coaxial camera 13. The reflected light detector 24 detects the light reflected from the reflecting element 4. The reflected light detector 24 includes a four-segment PSD 12.

[0066] The communication unit 25 communicates with an external device. The external device is, for example, a control system that controls a robot in which the reflective element 4 is installed. The communication unit 25 includes a transmission unit and a reception unit. The transmission unit transmits the position information of the reflective element 4 acquired by a position information acquisition unit included in the distance measurement unit 200 to the control system. The communication unit 25 includes a communication interface (I / F) for communicating via a wireless network.

[0067] For example, a fifth generation mobile communication system or a mobile communication system using light with a wavelength shorter than millimeter waves may be used for communication by the communication unit 25. In the fifth generation mobile communication system, frequency bands of 450 MHz to 6000 MHz and 24250 MHz to 52600 MHz are used.

[0068] The moving device 27 is movable. The moving device 27 includes the moving device 3. That is, the moving device 27 includes, for example, an AGV or an AMR.

[0069] Next, the position measurement process performed by the mobile position measurement device 1 will be described with reference to Fig. 5. Fig. 5 is a diagram showing an example of the position measurement process according to this embodiment. The position measurement process is executed by the control unit 22. The control unit 22 uses the first imaging unit 23 to capture an image of the reflecting element 4 (step S10). Note that the control unit 22 may use the first imaging unit 23 to capture an image of at least a part of the robot to be measured and / or the reflecting element 4.

[0070] The imaging adjustment unit included in the control unit 22 adjusts the imaging direction of the first imaging unit 23 so that the reflective element 4 is included in the imaging range of the first imaging unit 23. The imaging direction is, for example, the direction of the optical axis of the imaging lens. If the optical path for imaging is bent by the beam steering mirror 14, the optical axis of the imaging lens may include the bent optical axis. In adjusting the imaging direction of the first imaging unit 23, the imaging adjustment unit may adjust the direction of the optical axis of the imaging lens so that it overlaps with the reflective element 4, or may adjust the direction so that the reflective element 4 is included in the imaging range even if it does not overlap. The imaging adjustment unit determines whether the reflective element 4 is included in the imaging range of the first imaging unit 23 based on the image captured by the first imaging unit 23. The imaging adjustment unit has an image analysis function and determines the image of the reflective element 4 by analyzing the image captured by the first imaging unit 23. The imaging adjustment unit determines the image of the reflective element 4 based on, for example, pattern matching. The irradiation direction moving unit 201 may learn images of the reflective element 4 in advance using AI (machine learning) and determine the image of the reflective element 4 based on the learning results. Immediately after detecting the reflective element 4 by pattern matching, the imaging adjustment unit may determine the feature information (color information and / or luminance information of the pixel) of the pixel region determined to be the reflective element 4 from the captured image at the time when the reflective element 4 is detected or immediately before or after the time when the reflective element 4 is detected, and may determine the position of the image of the reflective element 4 by searching for similar feature information (color information and / or luminance information of the pixel) in the subsequent frame.

[0071] Regarding the imaging direction of the first imaging unit 23, the position at which the mobile position measurement device 1 is installed and / or the orientation of the housing 10 may be adjusted in advance so that the imaging range of the first imaging unit 23 includes the reflective element 4. In this case, the imaging adjustment unit may be omitted from the configuration of the control unit 22.

[0072] Based on the imaging result by the first imaging unit 23, the control unit 22 controls the irradiation direction shifting unit 201 so that the measurement light is irradiated onto the reflecting element 4 (step S20). The irradiation direction shifting unit 201 changes the orientation of the beam steering mirror 14 using the irradiation direction measurement result obtained by the rotary encoder. The irradiation direction shifting unit 201 changes the orientation of the beam steering mirror 14 in the longitude and / or latitude directions via the gimbal unit. In other words, the irradiation direction shifting unit 201 shifts the irradiation direction in accordance with a command from the control unit 22 so that the measurement light is irradiated onto the reflecting element 4 that is the measurement target determined based on the imaging result by the first imaging unit 23.

[0073] The latitude direction is the direction indicated by the angle between a first predetermined axis (Z axis in the example shown in FIG. 3) and the radius vector in a spherical coordinate system. The longitude direction is the direction indicated by the angle between a second predetermined axis (X axis in the example shown in FIG. 3) included in a plane perpendicular to the first predetermined axis and the projection of the radius vector onto the plane.

[0074] Here, the control unit 22 further controls the irradiation direction moving unit 201 so that the measurement light follows the movement of the reflective element 4 to be measured, based on the imaging result by the first imaging unit 23. Since the irradiation direction moving unit 201 is driven so that the measurement light follows the reflective element 4, even if the reflective element 4 moves, the measurement light continues to irradiate the reflective element 4, and the first imaging unit 23 can continue to image the reflective element 4.

[0075] Furthermore, when changing the measurement target, the position of the changed measurement target can be identified by capturing an image of the reflecting element 4 installed on the new measurement target. For example, when changing the measurement target from robot R1 to robot R2 in Fig. 1, the first imaging unit 23 changes the imaging target from the reflecting element 4 installed on robot R1 to the reflecting element 4 installed on robot R2, and identifies the position of robot R2.

[0076] The irradiation direction moving unit 201 determines the image of the reflecting element 4 by performing image analysis on the image captured by the first imaging unit 23. In the process of driving the irradiation unit to follow the reflecting element 4, the irradiation direction moving unit 201 repeatedly performs image analysis to determine the image of the reflecting element 4 at each time.

[0077] As described above, the first imaging unit 23 receives light from the space in which the reflecting element 4 is disposed. In other words, the first imaging unit 23 is included in the second detection unit that receives light from the space in which the reflecting element 4 is disposed. The irradiation direction shifting unit 201 determines the position of the reflecting element 4 to be measured based on the detection result by the second detecting unit, and shifts the irradiation direction of the measurement light.

[0078] In this way, the measurement light from the optical comb interferometer 11 included in the distance measurement unit 200 is irradiated toward the reflecting element 4 (step S30). When the measurement light is irradiated onto the reflecting element 4, the reflected light is reflected by total reflection.

[0079] The reflective element 4 does not have to be a total reflection element. For example, a corner cube reflector may be used as the reflective element 4. The corner cube reflector may be a corner cube reflective element having a reflection-enhancing coating. The reflective element 4 may also be a ball reflector or a cat's eye.

[0080] Here, in the process of capturing an image of the reflecting element 4 (step S10) described above, the moving device 3 may be moving. The process of controlling the irradiation direction moving unit 201 so that the measuring light is irradiated onto the reflecting element 4 based on the imaging result by the first imaging unit 23 (step S20) is executed after the moving device 3 has stopped. Therefore, the process of irradiating the measuring light towards the reflecting element 4 (step S30) is executed after the moving device 3 has stopped. In other words, the irradiating unit provided in the distance measuring unit 200 irradiates the measuring light onto the reflecting element 4 after the moving device 3 has stopped. Note that the irradiating unit provided in the distance measuring unit 200 may irradiate the measuring light onto the reflecting element 4 while the moving device 3 is moving (while the moving device 3 is moving).

[0081] The reflected light from the reflecting element 4 travels along the same path as the measurement light in the opposite direction and is received by the light receiving unit of the distance measurement unit 200, which includes the optical comb interferometer 11 (step S40). A portion of the reflected light is detected by the four-segment PSD 12. Based on the detection result from the four-segment PSD 12, the control unit 22 again controls the irradiation direction shifting unit 201 so that the measurement light continues to be irradiated onto the reflecting element 4. Here, based on the detection result from the four-segment PSD 12, the control unit 22 fine-tunes the irradiation direction of the measurement light using the irradiation direction shifting unit 201.

[0082] Here, the four-segment PSD 12 receives light from the space in which the reflecting element 4 is disposed. The four-segment PSD 12 is included in a first detection unit that receives light from the space in which the reflecting element 4 is disposed. Therefore, the irradiation direction movement unit 201 determines the position of the reflecting element 4 to be measured based on the detection result by the first detection unit, and drives the irradiation unit provided in the distance measurement unit 200 so that the measurement light is irradiated onto the reflecting element 4.

[0083] In the mobile position measuring device 1, even if the measurement light is lost during the measurement process, the irradiation direction moving unit 201 can drive the irradiation unit so that the measurement light is irradiated onto the reflecting element 4 with an accuracy on the order of submicrometers by the optical comb interferometer 11. For example, the measurement light is lost when an obstacle remains between the distance measuring unit 200 and the reflecting element 4.

[0084] The position information acquisition unit 203 acquires position information of the reflecting element 4 from the detection result (distance information) by the distance measurement unit 200 including the optical comb interferometer 11 and the direction information measured by the irradiation direction measurement unit 202 (step S50). The acquired position information is output to the calculation unit 26 via the control unit 22. The position information is expressed in three-dimensional spherical coordinates with the position measurement device 2 as the reference. At this time, the position information may be converted into Cartesian coordinates with the position measurement device 2 as the reference.

[0085] The control unit 22 transmits the position information acquired by the position information acquisition unit to a control system (step S60). The control system is a control system that controls a robot equipped with the reflective element 4. The control unit 22 causes the communication unit 25 to transmit the position information by wireless communication. With this, the control unit 22 ends the position measurement process.

[0086] The control system controls the robot based on the position information received from the mobile position measurement device 1. The control system calibrates the position of the moving part of the robot based on the position information.

[0087] In the present embodiment, an example has been described in which the mobile position measurement device 1 measures the position information of the reflecting element 4, but the present invention is not limited to this. The mobile position measurement device 1 may transmit at least one of distance information and direction information to the control system as the measurement result.

[0088] (Second embodiment) The second embodiment of the present invention will be described in detail below with reference to the drawings. In the first embodiment, the mobile position measuring device 1 is described as using the image of the reflective element 4 captured by the first imaging unit 23 (coaxial camera 13) to change the irradiation direction of the measurement light. In the present embodiment, a case will be described in which, before the first imaging unit 23 captures the image of the reflective element 4, the second imaging unit, which has an imaging range wider than the imaging range of the first imaging unit 23, captures the image of the reflective element 4 in advance. The mobile position measuring device according to this embodiment is referred to as a mobile position measuring device 1a, and the position measuring device is referred to as a position measuring device 2a. The same components as those in the first embodiment described above are denoted by the same reference numerals, and the description of the same components and operations may be omitted.

[0089] 6 is a diagram showing an example of the configuration of a position measurement device 2a according to this embodiment. The position measurement device 2a includes a housing 10, an optical comb interferometer 11, a four-segment PSD 12, a coaxial camera 13, a beam steering mirror 14, a PMA 15, a first half mirror 16, a second half mirror 17, and a 360-degree camera 18.

[0090] The 360-degree camera 18 captures images of its surroundings in a 360-degree range. The 360-degree camera 18 captures images of its surroundings in a 360-degree range by periodically rotating an imaging unit having a predetermined imaging range in the horizontal direction. In the following description, the imaging range is indicated by the horizontal angle of view and / or the vertical angle of view. The horizontal angle of view is the angle of view in the horizontal direction, and the vertical angle of view is the angle of view in the vertical direction. The imaging range of the 360-degree camera 18 has a horizontal angle of view of 360 degrees and a vertical angle of view of, for example, -45 degrees to 225 degrees.

[0091] The imaging range of the 360-degree camera 18 includes the robot on which the reflective element 4 is installed. It is assumed that there are no objects (obstacles) between the 360-degree camera 18 and the robot that would prevent the robot from being included in the imaging range of the 360-degree camera 18.

[0092] Furthermore, the accuracy of the position of the reflecting element 4 determined based on the image of the reflecting element 4 captured by the 360-degree camera 18 is coarser than the accuracy of the position of the reflecting element 4 determined based on the image of the reflecting element 4 captured by the coaxial camera 13.

[0093] The position measurement device 2a may be provided with a camera having a predetermined angle of view instead of the 360-degree camera 18. The camera may be a wide-angle camera having a horizontal angle of view of, for example, 120 to 150 degrees. The angle of view of the camera may also be larger or smaller than the horizontal angle of view of 120 to 150 degrees.

[0094] 7 is a diagram showing an example of the functional configuration of a position measurement device 2a according to this embodiment. The position measurement device 2a includes a position measurement unit 20, a control unit 22, a first image capture unit 23, a reflected light detection unit 24, a communication unit 25, a moving device 27, and a second image capture unit 28.

[0095] The second imaging unit 28 captures an image of the reflecting element 4. The imaging range of the second imaging unit 28 is wider than the imaging range of the first imaging unit 23. The second imaging unit 28 includes a 360-degree camera 18. Note that the second imaging unit 28 may be provided with a camera having a predetermined angle of view instead of the 360-degree camera 18. The camera may be, for example, a wide-angle camera having a horizontal angle of view of 120 to 150 degrees. The angle of view of the camera may also be larger or smaller than the horizontal angle of view of 120 to 150 degrees.

[0096] Next, the position measurement process performed by the mobile position measurement device 1a will be described with reference to Fig. 8. Fig. 8 is a diagram showing an example of the position measurement process according to this embodiment. The position measurement process is executed by the control unit 22.

[0097] The imaging adjustment section provided in the control section 22 uses the second imaging section 28 to capture an image of the robot to be measured (step S110). The imaging adjustment section may use the second imaging section 28 to capture an image of at least a part of the robot.

[0098] The imaging adjustment section provided in the control section 22 determines the position of the robot to be measured based on the imaging results of the second imaging section 28 (step S120). Here, the imaging adjustment section provided in the control section 22 determines the image of the robot within the angle of view of the imaging results of the second imaging section 28 based on image analysis. The imaging adjustment section determines the image of the robot based on image analysis such as pattern matching and / or machine learning, thereby determining the position of the robot.

[0099] FIG. 9 shows an example of the imaging result of the second imaging unit 28. The imaging range D1 indicates a 360-degree range around the position measurement device 2 imaged by the second imaging unit 28. The imaging range D2 indicates the imaging range of the first imaging unit 23. The imaging range of the first imaging unit 23 is, for example, substantially rectangular. In the example shown in FIG. 9, the images of robot R91, robot R92, robot R93, and robot R94 are included in the imaging range D1. In the example shown in FIG. 9, the reflective element 4 installed on robot R91 is included in the imaging range D2.

[0100] Here, the imaging range of second imaging unit 28 is wider in both the horizontal and vertical directions than the imaging range of first imaging unit 23. Therefore, the imaging adjustment unit determines the position of reflecting element 4 in both the horizontal and vertical directions based on the imaging results of second imaging unit 28.

[0101] 9 is the imaging range of the 360-degree camera 18 when the second imaging unit 28 is equipped with the 360-degree camera 18. When the second imaging unit 28 is equipped with a camera having a predetermined angle of view instead of the 360-degree camera 18, the imaging range D1 changes depending on the angle of view. For example, when the second imaging unit 28 is equipped with a wide-angle camera having a horizontal angle of view of 120 to 150 degrees, the imaging range D1 indicates a range of 120 to 150 degrees around the position measurement device 2.

[0102] Furthermore, if second imaging unit 28 is equipped with an omnidirectional camera having a horizontal angle of view of 360 degrees and a vertical angle of view of 180 degrees, imaging range D1 will be an imaging range with a horizontal angle of view of 360 degrees and a vertical angle of view of 180 degrees, like an omnidirectional image. Furthermore, if second imaging unit 28 is equipped with a hemispherical camera having a horizontal angle of view of 360 degrees and a vertical angle of view smaller than 180 degrees, imaging range D1 will be an imaging range with a horizontal angle of view of 360 degrees and a vertical angle of view smaller than 180 degrees, like an hemispherical image.

[0103] Returning to FIG. 8, the description of the position measurement process will be continued. The imaging adjustment section provided in the control section 22 adjusts the imaging direction of the first imaging section 23 (step S130). Here, the imaging adjustment section provided in the control section 22 determines the position of the robot to be measured based on the imaging result by the second imaging section 28, and adjusts the imaging direction of the first imaging section 23 so that it faces the position of the robot.

[0104] Here, the imaging adjustment unit adjusts the imaging direction of the first imaging unit 23 so that it follows the robot to be measured, based on the imaging results by the second imaging unit 28. The imaging adjustment unit causes the imaging direction of the first imaging unit 23 to follow the robot by performing image recognition of a predetermined object included in the imaging results by the second imaging unit 28. The predetermined object is, for example, one or more of the following: a feature of the entire robot, a feature of the tip of the robot arm, a feature of a part of the robot other than the tip, a feature of a mark attached to the robot, an end effector attached to the tip of the robot, a reflective element, etc. Because the imaging direction of the first imaging unit 23 is adjusted so that it follows the robot, the first imaging unit 23 can continue to capture an image of the robot even if the robot moves.

[0105] Note that the measurement target whose position is determined in step S120 is not limited to the current measurement target whose imaging direction is to be tracked by the first imaging unit 23. The control unit 22 may determine the position of a robot to be a new measurement target based on the imaging results of the second imaging unit 28. For example, in the example shown in FIG. 9 above, the imaging adjustment unit included in the control unit 22 determines the position of robot R91 as the measurement target. However, when the measurement target is changed from robot R91 to robot R92, robot R93, robot R94, etc., the imaging adjustment unit included in the control unit 22 may determine the position of the robot to be measured based on the imaging results of the second imaging unit. In this case, for multiple measurement targets, the imaging adjustment unit included in the control unit 22 may determine the position of the measurement target after the measurement target is changed based on the first imaging unit 23. In other words, after the measurement target is changed, the imaging direction may be adjusted so as to face the position of the measurement target (so as to track the measurement target) based on the imaging results of the first imaging unit. The imaging adjustment unit provided in the control unit 22 adjusts the imaging direction of the first imaging unit 23 to the changed measurement object, so that even if the measurement object is changed, the first imaging unit 23 can image the changed measurement object.

[0106] The second imaging unit 28 receives light from a space in which the measurement object having the reflecting element 4 is disposed. The second imaging unit 28 is included in a third detection unit that receives light from a space in which the measurement object having the reflecting element 4 is disposed. The imaging adjustment unit moves the detection direction of the second detection unit that receives light from the space in which the reflecting element 4 is disposed, based on the detection result by the third detection unit. The imaging adjustment unit is a detection direction movement unit that moves the detection direction of the second detection unit, based on the detection result by the third detection unit. The second detection unit includes a first imaging unit 23. The third detection unit includes a second imaging unit 28 having a wider imaging range than the first imaging unit 23. The imaging range of the second imaging unit 28 is wider than the imaging range of the first imaging unit 23, but the adjustment accuracy based on the imaging results by the second imaging unit 28 is lower than the adjustment accuracy based on the imaging results by the first imaging unit 23.

[0107] The processes from step S140 to step S190 are the same as the processes from step S10 to step S60 in FIG. 5, and therefore will not be described again. With this, the control unit 22 ends the position measurement process.

[0108] The position where the mobile position measurement device 1a stops may be determined based on the imaging results of the second imaging unit 28. In this case, the first imaging unit 23 may not be provided. The mobile position measurement device 1a moves within the factory to a measurement position where the position of the measurement object is measured. The control unit 22 captures an image of the measurement object in advance using the second imaging unit 28 before starting measurement, and determines the measurement position based on the imaging results of the second imaging unit 28. The mobile position measurement device 1a moves within the factory to the determined measurement position and stops at the measurement position. In this case, the control unit 22 may determine the measurement position while the mobile position measurement device 1a is stopped before starting measurement, or while the mobile position measurement device 1a is moving.

[0109] Furthermore, for example, when the mobile position measurement device 1a determines that the position of the measurement target is far from the position of the mobile position measurement device 1a based on the imaging results of the second imaging unit 28, it first moves closer to the measurement target. At this time, the mobile position measurement device 1a moves while changing its own orientation so that it is in an orientation that makes it easy to measure the measurement target. An orientation that makes it easy to measure the measurement target is, for example, an orientation in which the reflecting element 4 is visible from the front. The mobile position measurement device 1a determines the orientation in which the reflecting element 4 is visible from the front, for example, by determining an image of the front of the reflecting element 4 based on image recognition. The mobile position measurement device 1a may determine, as the orientation in which the reflecting element 4 is visible from the front, the imaging direction of the second imaging unit 28 in which the area of ​​the image of the reflecting element 4 in the image captured by the second imaging unit 28 is largest.

[0110] (Third embodiment) The third embodiment of the present invention will be described in detail below with reference to the drawings. The position measurement results obtained by a mobile position measurement device may be affected by vibrations of the mobile position measurement device itself. In this embodiment, a case will be described in which the mobile position measurement device measures position only when the mobile position measurement device itself is not vibrating or when the mobile position measurement device is in an environment with negligible vibrations of the mobile position measurement device itself. Negligible vibrations of the mobile position measurement device itself are vibrations that do not affect the accuracy required for measuring the position of the object to be measured. The mobile position measurement device may be provided with a vibration suppression mechanism and / or an anti-vibration mechanism to suppress vibrations in the position measurement unit. The mobile position measuring device according to this embodiment is referred to as mobile position measuring device 1b, and the position measuring device is referred to as position measuring device 2b. The same components as those in the above-described embodiments are denoted by the same reference numerals, and descriptions of the same components and operations may be omitted.

[0111] 10 is a diagram showing an example of the functional configuration of a position measurement device 2b according to this embodiment. The position measurement device 2b includes a position measurement unit 20, a control unit 22, a first imaging unit 23, a reflected light detection unit 24, a communication unit 25, a moving device 27, and a vibration detection unit 29. Note that the position measurement device 2b may also include a second imaging unit 28, similar to the position measurement device 2a according to the second embodiment described above.

[0112] The vibration detection unit 29 detects vibrations of at least a part of the position measurement device 2b. The vibration detection unit 29 includes one or more of a velocity sensor, an acceleration sensor, an angular velocity sensor, an angular acceleration sensor, and a gyro sensor.

[0113] The vibration detection unit 29 detects the amount of vibration in at least one of the directions of roll, pitch, and yaw. Roll, pitch, and yaw refer to, for example, rotation around the X axis, rotation around the Y axis, and rotation around the Z axis, respectively. The vibration detection unit 29 may also detect high-frequency vibration and low-frequency vibration separately by analyzing the amount of vibration over time.

[0114] The vibration detection unit 29 may detect vibration of the position measurement device 2b based on an image captured by the first imaging unit 23. When the position measurement device 2b is vibrating, the first imaging unit 23 provided in the housing 10 vibrates. In this case, the image captured by the first imaging unit 23 captures the vibration of the reflective element 4, the scenery, or the like. Furthermore, when the position measurement device 2b is provided with the second imaging unit 28, the vibration detection unit 29 may detect vibration of the position measurement device 2b based on an image captured by the second imaging unit 28.

[0115] Next, the position measurement process performed by the mobile position measurement device 1b will be described with reference to Fig. 11. Fig. 11 is a diagram showing an example of the position measurement process according to this embodiment. The position measurement process is executed by the control unit 22. The processes in steps S110, S120, and S150 to S180 are similar to the processes in steps S10, S20, and S30 to S60 in FIG. 5, and therefore will not be described further.

[0116] The control unit 22 determines whether or not vibration has been detected by the vibration detection unit 29 (step S130). When the vibration detection unit 29 detects vibration, it outputs a detection result indicating the amount of vibration to the control unit 22. When the control unit 22 acquires the vibration detection result from the vibration detection unit 29, it determines that vibration has been detected.

[0117] Note that the control unit 22 may determine the presence or absence of vibration based on the frequency of the vibration, even if the vibration magnitude is the same. For example, the control unit 22 may determine that vibration is not detected in the case of high-frequency (long-period) vibration, and may determine that vibration is detected in the case of low-frequency (short-period) vibration. The threshold for determining whether the frequency is low or high may be determined based on the time it takes for the position measurement device 2b to measure the position of the measurement object.

[0118] When it is determined that vibration has been detected by the vibration detection unit 29 (step S130; YES), the control unit 22 determines whether the vibration magnitude of the vibration is smaller than a predetermined amount (also referred to as vibration stop sensitivity) (step S140). Here, the control unit 22 makes the determination by comparing the vibration magnitude indicated by the detection result acquired from the vibration detection unit 29 with the predetermined amount.

[0119] The vibration stopping sensitivity may be preset as a design value when the position measurement device 2b is manufactured, or may be set by the user of the position measurement device 2b. When the vibration stopping sensitivity is set by the user, the user can easily set the vibration stopping sensitivity by selecting a value indicating the level of the vibration stopping sensitivity. For example, the user selects one of three values, such as "large," "medium," or "small," as the value indicating the level of the vibration stopping sensitivity. In this case, the control unit 22 sets the vibration stopping sensitivity to a predetermined setting value corresponding to the selected value. Note that when the vibration stopping sensitivity is set by the user, the user may set the vibration stopping sensitivity by continuously changing it, or the user may input a value for the vibration stopping sensitivity.

[0120] When the control unit 22 determines that the vibration amount is smaller than the predetermined amount (step S140; YES), it executes the processes of step S150 and thereafter. That is, the control unit 22 irradiates the reflecting element 4 with the measurement light when the vibration amount detected by the vibration detection unit 29 is smaller than the predetermined amount. When the control unit 22 determines that the vibration amount is greater than the predetermined amount (step S140; NO), the control unit 22 ends the position measurement process. That is, when the vibration amount of the position measurement device 2 is greater than the predetermined amount, the control unit 22 ends the position measurement process without irradiating the measurement light.

[0121] On the other hand, when vibration is not detected by vibration detection unit 29 (step S130; NO), control unit 22 executes the processes from step S150 onwards. Therefore, control unit 22 irradiates measurement light onto reflecting element 4 when vibration is not detected by vibration detection unit 29. That is, the irradiating unit provided in distance measurement unit 200 irradiates measurement light onto reflecting element 4 based on the detection result by vibration detection unit 29. With this, the control unit 22 ends the position measurement process.

[0122] In the present embodiment, the control unit 22 ends the position measurement process without irradiating the measurement light when the vibration amount is greater than a predetermined amount, but this is not limited to this. When vibration is detected by the vibration detection unit 29, the control unit 22 may end the position measurement process without irradiating the measurement light regardless of the vibration amount.

[0123] In addition, when vibration is detected by the vibration detection unit 29, the control unit 22 may control the distance measurement unit 200 to irradiate measurement light, and then control the calculation unit 26 not to perform signal processing to calculate the distance. Furthermore, when vibration is detected by vibration detection unit 29 and the vibration amount is greater than a predetermined amount, control unit 22 may control distance measurement unit 200 to irradiate measurement light and then not cause calculation unit 26 to execute signal processing for calculating position information. That is, in this case, position measurement unit 20 acquires position information of reflecting element 4 based on the light reception result of light received by a light receiving unit included in optical comb interferometer 11 when the vibration amount detected by vibration detection unit 29 is smaller than the predetermined amount.

[0124] In addition, when vibration is detected by vibration detection unit 29, control unit 22 may, regardless of the amount of vibration, cause distance measurement unit 200 to irradiate measurement light, and then cause calculation unit 26 to perform signal processing to calculate position information, and then determine whether or not to cause position measurement unit 20 to acquire the position information calculated by calculation unit 26.

[0125] In this case, the control unit 22, for example, causes the calculation unit 26 to generate reliability information based on the vibration amount indicated by the detection result by the vibration detection unit 29. The reliability information indicates a lower reliability as the vibration amount indicated by the detection result increases, and a higher reliability as the vibration amount decreases. If the reliability information indicates a reliability higher than a predetermined value, the control unit 22 causes the position measurement unit 20 to acquire the position information calculated by the calculation unit 26. On the other hand, if the reliability information indicates a reliability lower than the predetermined value, the control unit 22 does not cause the position measurement unit 20 to acquire the position information calculated by the calculation unit 26.

[0126] (Fourth embodiment) The fourth embodiment of the present invention will be described in detail below with reference to the drawings. When measuring the position information of a measurement target using the mobile position measurement device 1, fluctuations in the relative relationship between the position of the mobile position measurement device 1 and the position of the measurement target can affect the measurement results as errors. Such fluctuations can be caused, for example, by vibrations of the floor on which the measurement target is placed. Furthermore, when the mobile position measurement device 1 and the robot to be measured are installed inside a large workpiece, such fluctuations can occur when a reaction force caused by the robot's movement is transmitted to the mobile position measurement device 1.

[0127] In this embodiment, we will explain a case where a mobile position measurement device corrects the effect on the measurement results of location information due to changes in the relative relationship between the mobile position measurement device and the position of the object to be measured, based on the displacement of the mobile position measurement device relative to the reference position. In this embodiment, calibration of the origin will also be described.

[0128] The mobile position measuring device according to this embodiment is referred to as a mobile position measuring device 1c, and the position measuring device is referred to as a position measuring device 2c. The same components as those in the above-described embodiments are denoted by the same reference numerals, and descriptions of the same components and operations may be omitted.

[0129] FIG. 12 is a diagram showing an example of how the mobile position measuring device 1c according to this embodiment measures a reference position. In this embodiment, the object to be measured is, for example, a machine tool. The reflecting element 4c is disposed on a movable part of the machine tool. Here, in this embodiment, the machine tool has a machining head, which has an end effector such as an end mill. The movable part of the machine tool is, for example, a mechanism for changing the angle and position of the end mill to a desired angle and position. The reference reflecting element 5 includes, for example, three reference reflecting elements: a first reference reflecting element 5-1, a second reference reflecting element 5-2, and a third reference reflecting element 5-3.

[0130] The reference position is a predetermined position (for example, the origin) in a three-dimensional coordinate system based on the multiple reference reflecting elements 5. The position of the origin of the three-dimensional coordinate system is, for example, the position of any one of the multiple reference reflecting elements 5. In the following description, the first reference reflecting element 5-1, the second reference reflecting element 5-2, and the third reference reflecting element 5-3 may be collectively referred to as a plurality of reference reflecting elements 5.

[0131] Each of the plurality of reference reflective elements 5 is a retroreflector, that is, each of the plurality of reference reflective elements 5 has a retroreflection function similar to the reflective element 4c.

[0132] The mobile position measuring device 1c includes a reference measurement light irradiator 19. The reference measurement light irradiator 19 is provided as part of the optical comb interferometer 11. The reference measurement light irradiator 19 includes a first reference irradiator, a second reference irradiator, and a third reference irradiator. In this embodiment, the position measurement device 2c includes an optical system inside the housing 10 for branching the measurement light emitted from the optical comb interferometer 11. In the position measurement device 2c, the optical system can branch the measurement light into up to eight beams. In this embodiment, the first, second, and third reference measurement beams irradiated by the reference measurement beam irradiator 19 are beams obtained by branching the measurement light emitted from the optical comb interferometer 11.

[0133] The first light receiving unit that receives the first reference reflected light, the second light receiving unit that receives the second reference reflected light, and the third light receiving unit that receives the third reference reflected light are provided separately from the light receiving units provided in the optical comb interferometer 11 that receive the reflected light reflected from the reflecting element 4c.

[0134] In this embodiment, an example will be described in which measurement light emitted from one optical comb interferometer 11 is branched and some of the branched measurement light is used as the first, second, and third reference measurement light, but this is not limiting. The position measurement device 2c may include, inside the housing 10, an optical comb interferometer that branches one measurement light and outputs the first, second, and third reference measurement light, in addition to the optical comb interferometer 11 that irradiates the measurement light.

[0135] The multiple reference reflecting elements 5 are each placed at a different predetermined position on the machine tool. The multiple reference reflecting elements 5 are placed at a position where measurement light can be irradiated from the mobile position measuring device 1c, such as behind the machine tool. The multiple reference reflecting elements 5 are also placed at a position where the reference measurement light irradiated onto each element can be irradiated without overlapping. In the example shown in Figure 12, each of the multiple reference reflecting elements 5 is placed on the base of the machine tool. The reference reflective element 5 may be placed above the robot or machine tool, or on the ceiling of the factory where the robot or machine tool is located.

[0136] In this embodiment, it is assumed that the reference reflecting element 5 is placed at a predetermined position within the machine tool (i.e., a predetermined fixed position), but the reference reflecting element 5 may be placed at a specific position on a movable part (i.e., a moving part) of the machine tool, and the reference position may be measured when the movable part is stationary. Also, the operator may place the reference reflecting element 5 at any position.

[0137] In the mobile position measuring device 1c, the position measuring device 2c is mounted on a moving device 3. Therefore, the optical comb interferometer 11 provided in the position measuring device 2c and the reference measurement light irradiator 19 provided in the optical comb interferometer 11 are provided on the moving device 3. The irradiation unit provided in the optical comb interferometer 11 is included in a first irradiation unit provided in the moving device 3, which irradiates a first reflecting element provided on the measurement object with a first measurement beam. The reference measurement light irradiator 19 is provided in the moving device 3 and is included in a reference irradiator that irradiates a reference reflection element related to a reference position in the space in which the moving device 3 is arranged with a reference measurement light. The signal processing unit provided in the optical comb interferometer 11 is included in a measurement unit that acquires position information or distance information regarding the first reflecting element relative to a reference position based on the first reflected light of the first measurement light from the first reflecting element and the reference reflected light of the reference measurement light from the reference reflecting element.

[0138] 13 is a diagram showing an example of the functional configuration of a position measurement device 2c according to this embodiment. The position measurement device 2c includes a position measurement unit 20, a reference position measurement unit 21, a control unit 22, a first image capture unit 23, a reflected light detection unit 24, a communication unit 25, a calculation unit 26, and a movement device 27.

[0139] As an example, the reference position measurement unit 21 includes three units: a reference position measurement unit 21-1, a reference position measurement unit 21-2, and a reference position measurement unit 21-3. Note that the number of reference position measurement units 21 may be other than three. In the following description, reference position measurement unit 21-1, reference position measurement unit 21-2, and reference position measurement unit 21-3 may be collectively referred to as reference position measurement unit 21. Because reference position measurement unit 21-1, reference position measurement unit 21-2, and reference position measurement unit 21-3 have similar functions, the functional configuration of reference position measurement unit 21 will be described here as a representative of reference position measurement unit 21, and descriptions of reference position measurement unit 21-2 and reference position measurement unit 21-3 will be omitted.

[0140] The reference position measurement unit 21-1 includes a reference distance measurement unit 210-1, a reference irradiation direction movement unit 211-1, a reference irradiation direction measurement unit 212-1, and a reference position information acquisition unit 213-1.

[0141] The reference distance measurement unit 210-1 irradiates the first reference reflecting element 5-1 with reference measurement light and receives the reference reflected light to measure the distance to the first reference reflecting element 5-1. The reference distance measurement unit 210-1 includes a first reference irradiating unit, a first reference light receiving unit, and a first reference signal processing unit.

[0142] The first reference irradiator irradiates the first reference reflecting element 5-1 with the first reference measurement light. The first reference irradiator includes an optical system for splitting the measurement light emitted from the optical comb interferometer 11. The first reference light receiving section receives the first reference reflected light from the first reference reflecting element 5-1 and includes a light receiving section provided inside the housing 10 of the mobile position measuring device 1c.

[0143] The first reference signal processing unit processes the signal from the first reference light receiving unit to obtain first reference distance information, which indicates the distance from the mobile position measurement device 1c to the first reference reflecting element 5-1.

[0144] The reference irradiation direction moving unit 211-1 changes the irradiation direction of the reference measurement light. Changing the irradiation direction is also referred to as moving the irradiation direction. The reference irradiation direction moving unit 211-1 includes a gimbal unit included in the PMA 15. The reference irradiation direction measurement unit 212-1 measures the irradiation direction of the reference measurement light. The reference position information acquisition unit 213-1 acquires the position of the first reference reflecting element 5-1 in three-dimensional space (first reference position information) from the distance (distance information) to the first reference reflecting element 5-1 measured by the reference distance measurement unit 210 and the irradiation direction (direction information) of the reference measurement light measured by the reference irradiation direction measurement unit 212-1. The acquisition of the reference position information will be described in detail later.

[0145] The reference position measurement unit 21-2 irradiates the second reference reflecting element 5-2 with a reference measurement light and receives the reference reflected light to measure the position of the second reference reflecting element 5-2. The reference position measurement unit 21-3 irradiates the third reference reflecting element 5-3 with a reference measurement light and receives the reference reflected light to measure the position of the third reference reflecting element 5-3. The functional configurations of the reference position measurement unit 21-2 and the reference position measurement unit 21-3 are the same as those of the reference position measurement unit 21-1, so detailed explanations will be omitted.

[0146] Note that any one of reference distance measurement unit 210-1, reference distance measurement unit 210-2, and reference distance measurement unit 210-3 may be simply referred to as reference distance measurement unit 210. Also, reference distance measurement unit 210-1, reference distance measurement unit 210-2, and reference distance measurement unit 210-3 may be collectively referred to as multiple reference distance measurement units 210. Furthermore, any one of the reference irradiation direction moving unit 211-1, the reference irradiation direction moving unit 211-2, and the reference irradiation direction moving unit 211-3 may be simply referred to as the reference irradiation direction moving unit 211. Furthermore, the reference irradiation direction moving unit 211-1, the reference irradiation direction moving unit 211-2, and the reference irradiation direction moving unit 211-3 may be collectively referred to as the plurality of reference irradiation direction moving units 211. Furthermore, any one of the reference irradiation direction measuring unit 212-1, the reference irradiation direction measuring unit 212-2, and the reference irradiation direction measuring unit 212-3 may be simply referred to as the reference irradiation direction measuring unit 212. Furthermore, the reference irradiation direction measuring unit 212-1, the reference irradiation direction measuring unit 212-2, and the reference irradiation direction measuring unit 212-3 may be collectively referred to as the plurality of reference irradiation direction measuring units 212. Furthermore, any one of reference position information acquisition unit 213-1, reference position information acquisition unit 213-2, and reference position information acquisition unit 213-3 may be simply referred to as reference position information acquisition unit 213. Furthermore, reference position information acquisition unit 213-1, reference position information acquisition unit 213-2, and reference position information acquisition unit 213-3 may be collectively referred to as a plurality of reference position information acquisition units 213.

[0147] The calculation unit 26 includes a reference coordinate setting unit 260 and a first correction unit 261. The reference coordinate setting unit 260 sets a reference (origin) and a reference coordinate system based on the first reference position information, the second reference position information, and the third reference position information.

[0148] The first correction unit 261 acquires position information of the reflecting element 4c relative to the reference generated by the reference coordinate setting unit 260. The position information of the reflecting element 4 relative to the reference includes acquiring position information of the reflecting element 4 in the set reference coordinate system. The first correction unit 261 further corrects fluctuations in the position information of the reflecting element 4 relative to the reference.

[0149] Here, the first correction unit 261 converts the position of the reflecting element 4 indicated by the position information based on the position of the mobile position measurement device 1c relative to the reference position indicated by the reference position information and the position of the reflecting element 4 indicated by the position information acquired by the position measurement unit 20. Through this conversion, the first correction unit 261 converts the position of the reflecting element 4 relative to the mobile position measurement device 1c into the position of the reflecting element 4 relative to the reference (origin). The first correction unit 261 generates information indicating the position of the reflecting element 4 in the reference coordinate system as corrected position information. Reference position information acquisition section 213 acquires the position information corrected by first correction section 261 as position information of reflecting element 4c relative to the reference (origin).

[0150] Next, the position measurement process performed by the mobile position measurement device 1c will be described with reference to Fig. 14. Fig. 14 is a diagram showing an example of the position measurement process according to this embodiment. The position measurement process is executed by the control unit 22.

[0151] The position measurement unit 20 acquires the position information of the reflecting element 4c (step S210). Here, the process of acquiring the position information of the reflecting element 4c in step S210 is the same as the position measurement process in Fig. 5 described above, and therefore a description thereof will be omitted.

[0152] The reference position measuring unit 21-1 acquires the reference position information of the first reference reflecting element 5-1 (step S220). Here, with reference to Fig. 15, the process by which the reference position measurement unit 21-1 generates reference position information of the first reference reflecting element 5-1 (referred to as reference position information generation process) will be described in detail. Fig. 15 is a diagram showing an example of the reference position information generation process according to this embodiment. The processes from step S310 to step S350 shown in Fig. 15 are executed as the process of step S220 shown in Fig. 14. The processes from step S310 to step S350 shown in FIG. 15 may be executed at the start of measurement.

[0153] The control unit 22 uses the first imaging unit 23 to capture images of the plurality of reference reflecting elements 5 (step S310).

[0154] The control unit 22 controls each of the plurality of reference irradiation direction moving units 211 so that each of the three reference measurement lights is irradiated onto each of the plurality of reference reflecting elements 5 (step S320). In the control of step S320, the control unit 22 uses the imaging results of the images of the plurality of reference reflecting elements 5 by the first imaging unit 23.

[0155] The control unit 22 controls the reference irradiation direction moving unit 211 so that the reference measurement light beams are irradiated onto the reference reflecting elements 5, respectively (step S330). The control unit 22 may cause the reference irradiators to irradiate the reference measurement light beams simultaneously or sequentially.

[0156] The control unit 22 determines that the reflected light from the reference reflecting element 5 travels along the same path as the reference measurement light in the opposite direction, and is received by the reference light receiving unit provided in the reference distance measurement unit 210 (step S340).

[0157] The reference position information acquisition unit 213 acquires reference position information of the reference reflecting element 5 from the measurement result (reference distance information) by the reference distance measurement unit 210 and the reference irradiation direction information acquired by the reference irradiation direction measurement unit 212 (step S350). In this embodiment, the reference position generation process described here is performed in each of the reference position measurement units 21-1, 21-2, and 21-3, and first reference position information, second reference position information, and third reference position information are acquired. The acquired first, second, and third reference position information are output to the calculation unit 26 via the control unit 22. The reference position information is expressed in three-dimensional spherical coordinates with the position measurement device 2 as the reference.

[0158] As described above, the reference position measurement unit 21 acquires position information of the reference reflecting element 5 in three-dimensional space from the distance to the reference reflecting element 5 measured by the reference distance measurement unit 210 and the irradiation direction of the reference measurement light measured by the reference irradiation direction measurement unit 212.

[0159] Returning to FIG. 14, the description of the position measurement process will be continued. The reference coordinate setting unit 260 included in the calculation unit 26 sets a reference (origin) and a reference coordinate system based on the first, second, and third reference position information acquired by the reference position measurement unit 21 and obtained via the control unit 22 (step S30). In this embodiment, at least three pieces of reference position information, first to third, are acquired, and the reference coordinate setting unit 260 sets a desired Cartesian coordinate system (reference coordinate system) based on these three pieces of reference position information.

[0160] The reference coordinate system can be arbitrarily set in the space in which the measurement object (reflecting element 4) moves, depending on the installation positions of the first reference reflecting element 5-1, the second reference reflecting element 5-2, and the third reference reflecting element 5-3. For example, as shown in FIG. 12, a Cartesian coordinate system can be set as the reference coordinate system, with respect to the space in which the movable part C2 of the measurement object moves, so as to include two axes parallel to the surface of the table on which the measurement object is placed. Furthermore, the reference coordinate setting unit 260 sets an origin as a reference within the reference coordinate system. The origin may be any of the three elements: the first reference reflecting element 5-1, the second reference reflecting element 5-2, and the third reference reflecting element 5-3 (reference position).

[0161] Alternatively, the movable part C2 (and thus the reflecting element 4), which is the object to be measured, may be positioned at a predetermined position in the reference coordinate system, for example, at the origin of the movable part C2 determined by the machine tool, and the position information of the reflecting element 4 at that time may be made to coincide with the origin of the reference coordinate system. This makes it possible to make the position information acquired by the position measurement unit 20 and the position information acquired by the reference position measurement unit 21 identical for the same position in space, thereby eliminating (correcting) any discrepancy between the position information acquired by the position measurement unit 20 and the position information acquired by the reference position measurement unit 21. In either case, the reference coordinate system and the reference (origin) are set based on the reference position information obtained from the reference reflecting element.

[0162] The first correction unit 261 included in the calculation unit 26 converts the position information of the reflecting element 4 into position information in the reference coordinate system (step S240). The first correction unit 261 converts the position information of the reflecting element 4 measured by the position measurement unit 20 from three-dimensional spherical coordinates based on the position measurement device 2 into Cartesian coordinates in the reference coordinate system set by the reference coordinate setting unit 260. This makes it possible to acquire the position information of the measurement object (i.e., the position information of the reflecting element 4) in Cartesian coordinates in the reference coordinate system in the space in which the measurement object moves.

[0163] The first correction unit 261 corrects the position information of the reflecting element 4c using the reference position information of the reference reflecting element 5 (step S250). The correction may include resetting the reference (origin) and the reference coordinate system set in step S230. For example, after starting to acquire the position information, an operation similar to step S230 may be performed at regular or irregular intervals to acquire the deviation of the reference coordinate system and correct the deviation. This makes it possible to calibrate the fluctuation of the origin over time (origin calibration). Alternatively, reference position information of the reference reflecting element 5 may be constantly acquired, and fluctuations in the reference (origin) and reference coordinate system may be constantly corrected. In this case, fluctuations (vibrations) over a short period of time can also be corrected.

[0164] In this way, by placing the reference reflecting element 5 on a measurement reference object that serves as a reference for measuring the position of the measurement object, and setting a reference coordinate system and an origin based on the reference position information of the reference reflecting element 5 acquired by the position measurement device 2, it is possible to cancel (correct) fluctuations in the relative positional relationship between the position measurement device 2 and the measurement object (reflecting element 4). In this sense, the conversion of the position information of the reflecting element 4 into position information in the reference coordinate system, performed by the first correction unit 261, can also be said to be a correction of the position information of the reflecting element 4.

[0165] As described above, the position information of the reflecting element 4c is acquired by the position information acquisition unit. The first correction unit 261 calculates the amount of displacement of the current position of the mobile position measurement device 1c relative to the reference position from the position of the mobile position measurement device 1c relative to the reference position at the time of origin calibration, based on the reference position information acquired by the reference position measurement unit 21. The first correction unit 261 corrects the position information of the reflecting element 4c by the calculated amount of displacement.

[0166] As described above, the position information of the reflecting element 4c is measured based on the light-receiving result by the light-receiving unit provided in the distance measurement unit 200. Therefore, the position information of the reflecting element 4c corrected based on the reference position information is position information generated based on the light-receiving result by the light-receiving unit provided in the distance measurement unit 200 and the reference position information. On the other hand, the reference position information is measured based on the light-receiving result by the first reference light-receiving unit, the light-receiving result by the second reference light-receiving unit, and the light-receiving result by the third reference light-receiving unit. Therefore, in the mobile position measurement device 1, position information of the reflecting element 4c relative to the reference position is generated based on the light-receiving result by the light-receiving unit provided in the distance measurement unit 200, the light-receiving result by the first reference light-receiving unit, the light-receiving result by the second reference light-receiving unit, and the light-receiving result by the third reference light-receiving unit.

[0167] The relative positional relationship between the mobile position measurement device 1c and the reference position may change due to floor vibrations, vibrations caused by the movement of the robot, etc. Even in such cases, the mobile position measurement device 1c can correct the position information of the reflecting element 4c based on the amount of displacement of the relative positional relationship between the mobile position measurement device 1c and the reference position.

[0168] The control unit 22 transmits the corrected position information to the control system (step S260). With this, the control unit 22 ends the position measurement process.

[0169] The control system receives the corrected position information transmitted from the mobile position measurement device 1c. The position of the measurement target measured by the mobile position measurement device 1c, indicated by the position information, is the position of the control target of the control system. If the position of the control target indicated by the received position information deviates from the assumed position, the control system performs calibration to offset the deviation between the position indicated by the received position information and the assumed position. The assumed position is a position that is assumed in advance for the control system to control the control target, such as a robot or machine tool. Alternatively, the control system may calculate a correction amount for control of the controlled object based on the received position information, and correct subsequent control based on the calculated correction amount. For example, in control subsequent to receiving the position information, the control system corrects the drive amount by the correction amount calculated based on the position information.

[0170] Here, in the process of capturing an image of the reference reflecting element 5 (step S310) described above, the mobile device 3 may be moving. Based on the imaging result by the first imaging unit 23, the process of causing the reference measurement light irradiator 19 to irradiate the reference measurement light toward the reference reflecting element 5 (step S320) is executed after the mobile device 3 has stopped. Therefore, the process of irradiating the reference measurement light toward the reference reflecting element 5 (step S330) is executed after the mobile device 3 has stopped. In other words, the reference measurement light irradiator 19 irradiates the reference measurement light toward the reference reflecting element 5 after the mobile device 3 has stopped. In addition, the position measurement unit 20 generates information regarding the reference position after the mobile device 3 has stopped.

[0171] The position measuring device 2c may also include a vibration detecting unit 29, similar to the position measuring device 2b according to the third embodiment. Similar to the position measurement device 2b according to the third embodiment, the vibration detection unit 29 detects vibrations of at least a portion of the position measurement device 2c. The position measurement unit 20 generates information about the reference position based on the detection result by the vibration detection unit 29. The reference measurement light irradiator 19 irradiates the reference reflecting element 5 with the reference measurement light based on the detection result by the vibration detection unit 29. For example, the reference measurement light irradiator 19 irradiates the reference reflecting element 5 with the reference measurement light when the vibration amount detected by the vibration detection unit 29 is smaller than a predetermined amount. In this case, the signal processor included in the optical comb interferometer 11 acquires information about the position of the reflecting element 4c based on the first reflected light of the first measurement light from the reflecting element 4c when the vibration amount detected by the vibration detection unit 29 is smaller than the predetermined amount, and the reference reflected light of the reference measurement light from the reference reflecting element 5. In other words, if the position measurement device 2c includes the vibration detection unit 29, it generates information about the reference position when the vibration amount detected by the vibration detection unit is smaller than the predetermined amount. The imaging result of the first imaging unit 23 may be corrected based on the detection result of the vibration detection unit 29.

[0172] As described above, the mobile position measuring device 1c includes the reference position measuring unit 21 that acquires information (reference position information) about the reference position in the space where the robot is placed. The reference position measuring unit 21 includes a first reference irradiating unit, a second reference irradiating unit, a third reference irradiating unit, a first reference light-receiving unit, a second reference light-receiving unit, and a third reference light-receiving unit. The first reference irradiator irradiates the first reference reflecting element 5-1 at the reference position with the first reference measurement light. The second reference irradiator irradiates the second reference reflecting element 5-2 at the reference position with the second reference measurement light. The third reference irradiator irradiates the third reference reflecting element 5-3 at the reference position with the third reference measurement light. In the mobile position measuring device 1, position information relative to the reference position of the first reflecting element (reflecting element 4c) is generated based on the light receiving results by the first light receiving unit (light receiving unit provided in the distance measuring unit 200), the light receiving results by the first reference light receiving unit, the light receiving results by the second reference light receiving unit, and the light receiving results by the third reference light receiving unit.

[0173] In this embodiment, an example has been described in which the mobile position measurement device 1c includes three irradiators (first reference irradiator, second reference irradiator, third reference irradiator), three light-receiving units (first reference light-receiving unit, second reference light-receiving unit, third reference light-receiving unit), and three reference reflecting elements (first reference reflecting element 5-1, second reference reflecting element 5-2, third reference reflecting element 5-3) to generate reference position information (i.e., measure the reference position), but is not limited to this. Other exemplary configurations for generating reference position information will be described below.

[0174] In this embodiment, the reference measurement light irradiating unit 19 can irradiate three reference measurement light beams simultaneously. Note that the reference measurement light irradiating unit 19 may irradiate three reference measurement light beams in sequence instead of irradiating three reference measurement light beams simultaneously.

[0175] Furthermore, instead of irradiating three reference measurement beams, one reference measurement beam may be irradiated to each of the three reference reflecting elements in turn. In this case, the reference position measuring unit 21 includes a reference irradiating unit and a reference light receiving unit. The reference irradiator irradiates the first reference reflecting element, the second reference reflecting element, and the third reference reflecting element at the reference position with the reference measurement light. The reference light receiving section receives a first reference reflected light from the first reference reflecting element, a second reference reflected light from the second reference reflecting element, and a third reference reflected light from the third reference reflecting element. Position information of the first reflecting element (reflecting element 4c) relative to the reference position is generated based on the light receiving result by the first light receiving unit (light receiving unit provided in distance measuring unit 200) and the light receiving result by the reference light receiving unit.

[0176] The position measurement device 2c may include three reference irradiators and one reference light receiver. In this case, the reference position measuring unit 21 includes a first reference irradiating unit, a second reference irradiating unit, a third reference irradiating unit, and a reference light receiving unit. The first reference irradiator irradiates the first reference reflecting element 5-1 at the reference position with the first reference measurement light. The second reference irradiator irradiates the second reference reflecting element 5-2 at the reference position with the second reference measurement light. The third reference irradiator irradiates the third reference reflecting element 5-3 at the reference position with the third reference measurement light. The reference light receiving section receives the first reference reflected light from the first reference reflecting element 5-1, the second reference reflected light from the second reference reflecting element 5-2, and the third reference reflected light from the third reference reflecting element 5-3. Position information of the first reflecting element (reflecting element 4c) relative to the reference position is generated based on the light receiving result by the first light receiving unit (light receiving unit provided in distance measuring unit 200) and the light receiving result by the reference light receiving unit.

[0177] Furthermore, in this embodiment, an example in which the number of reference reflecting elements 5 is three has been described, but the present invention is not limited to this. The number of reference reflecting elements 5 may be four or more. In order for the mobile position measuring device 1c to measure the displacement of the mobile position measuring device 1c relative to a reference position, one reference reflecting element 5 is sufficient. The number of reference reflecting elements 5 may be two.

[0178] For example, when the number of reference reflecting elements 5 is one, the reference position measuring unit 21 includes a reference irradiating unit and a reference light receiving unit. The reference irradiating section irradiates a reference reflecting element provided at a reference position with reference measurement light. The reference light receiving section receives the reference reflected light from the reference reflecting element. Position information of the first reflecting element (reflecting element 4c) relative to the reference position is generated based on the light receiving result by the first light receiving unit (light receiving unit provided in distance measuring unit 200) and the light receiving result by the reference light receiving unit.

[0179] In the present embodiment, an example has been described in which the mobile position measuring device 1c is irradiated with a reference measurement light for measuring the reference position in addition to the measurement light for measuring the position of the reflecting element 4c, but this is not limiting. The measurement light for measuring the position of the reflecting element 4c may also be used as the reference measurement light. In this case, the irradiation direction moving unit 201 adjusts the irradiation direction so that the measurement light is directed toward the reference reflecting element at the reference position. The light receiving section provided in the distance measuring section 200 receives the reference reflected light from the reference reflecting element. The position measurement unit 20 generates position information of the reflecting element 4c relative to a reference position based on the light reception result by the light receiving unit provided in the distance measurement unit 200.

[0180] Furthermore, when the measurement light for measuring the position of the reflecting element 4c is used as the reference measurement light, the irradiation unit provided in the optical comb interferometer 11 is moved by the moving device 3 to irradiate the measurement light onto the reference reflecting element 5 related to a reference position in the space in which the moving device 3 is disposed, and irradiate the measurement light onto the reflecting element 4c provided on the measurement object. The signal processing unit provided in the optical comb interferometer 11 acquires position information or distance information on the reflecting element 4c relative to the reference position based on the first reflected light of the measurement light from the reflecting element 4c and the reference reflected light of the measurement light from the reference reflecting element 5.

[0181] In addition, when the number of reference reflecting elements 5 is N, the number of reference measurement light beams irradiated from the reference irradiation unit is X, and the number of measurement light beams irradiated from the irradiation unit of the optical comb interferometer 11 and used as the reference measurement light beams is Y, as long as the condition that the sum of the number X and the number Y is equal to the number N is satisfied, measurements similar to those of the mobile position measuring device 1c of this embodiment can be performed using various combinations.

[0182] In the present embodiment, an example has been described in which the reference position information is used to correct the position information indicating the position of the reflecting element 4, but the present invention is not limited to this. For example, the reference position information may be used to determine the movement route of the mobile position measurement device 1c. Furthermore, when the mobile position measurement device 1c moves using the well-known SLAM (Simultaneous Localization and Mapping), the reference position information may be used to confirm whether the mobile position measurement device 1c is moving along the route indicated by the SLAM.

[0183] (Fifth embodiment) The fifth embodiment of the present invention will be described in detail below with reference to the drawings. In this embodiment, a case will be described in which the mobile position measuring device 1d holds a reflecting element to be installed on a robot that is the object of measurement. The mobile position measurement device according to this embodiment is referred to as a mobile position measurement device 1d, and the mobile device is referred to as a mobile device 3d. The same components as those in the above-described embodiments are denoted by the same reference numerals, and descriptions of the same components and operations may be omitted.

[0184] 16 is a diagram showing an example of the operation of a mobile position measurement device 1d according to this embodiment. The mobile position measurement device 1d includes a position measurement device 2 and a mobile device 3d. A robot T1 is an arm-type robot and is an example of a measurement target.

[0185] The moving device 3d includes a holding unit 30. The holding unit 30 detachably holds the reflecting element 4d. The holding unit 30 is provided on the moving device 3d. The holding unit 30 has a groove (not shown) for detachably holding the reflecting element 4d. The groove has a shape corresponding to the shape of the holder T10 that holds the reflecting element 4d. FIG. 16 shows a state in which reflecting elements 4d-2 and 4d-3 are held by the holding unit 30 as the reflecting elements 4d.

[0186] A holder T10 is provided at the tip of the arm of the robot T1. The holder T10 holds a reflecting element 4d. The reflecting element 4d is detachable from the holder T10. FIG. 16 shows a state in which a reflecting element 4d-1 is held by the holder T10 as an example of the reflecting element 4d. The holder T10 is an example of a holder provided on the robot that holds a reflecting element.

[0187] 17A and 17B are diagrams showing an example of how the reflecting element 4d according to this embodiment is attached to and detached from the holder T10. In Fig. 17A, the reflecting element 4d is held in a groove of the holding part 30. Here, the reflecting element 4d is held by the holding part 30 with the reflecting element facing downwards, as an example. 17(B), the reflecting element 4d is held by a holder T10. The robot T1 brings the tip of the arm on which the holder T10 is provided close to the holder 30 of the moving device 3d, and causes the reflecting element 4d to be held by the holder T10.

[0188] The holder T10 has a shape of a cylinder with a regular hexagonal bottom, for example. The reflecting elements 4d can be installed, for example, at three locations on the side of the cylinder. The bottom of the cylinder may have a polygonal surface shape other than a hexagon, a circular surface shape, an elliptical surface shape, or other surface shapes. In this embodiment, the bottom portion of the holder T10 is the bottom, but it may also have a spherical surface or other three-dimensional shape. At the time of measurement, one or more reflecting elements 4d may be installed on the holder T10. During measurement, the mobile position measuring device 1d may measure the position of any one of the three reflecting elements 4d installed on the three side surfaces of the holder T10.

[0189] In order to arrange the reflecting elements 4d at positions where the mobile position measuring device 1d can irradiate the measurement light, it is preferable to install a large number of reflecting elements 4d in the holder T10. As described above, the holder T10 has a cylindrical shape with a regular hexagonal base, and therefore, as shown in Fig. 17, the irradiation unit of the optical comb interferometer 11 can irradiate the measurement light from any direction within a 360-degree angle around the holder T10.

[0190] The plurality of reflecting elements 4d may include a plurality of types of reflecting elements. The plurality of types may refer to, for example, the materials, sizes, structures, etc. of the reflecting elements. An example of the plurality of structures may be a structure combining flat mirrors and a spherical structure. Each of the plurality of reflecting elements 4d may be assigned an identifier, which allows the mobile position measurement device 1d to identify which of the plurality of reflecting elements 4d is installed in a holder T10 provided in the robot T1 or held in a holding unit 30 of the mobile position measurement device 1d.

[0191] The reflective element 4d is not required except for position measurement, and therefore does not need to be permanently installed on the robot T1. If the reflective element 4d is permanently installed on the robot T1, the surface of the reflective element 4d may become dirty. Dirt on the surface of the reflective element 4d may cause errors in position measurement using measurement light.

[0192] In the mobile position measurement device 1d, the reflecting element 4d is held by the holder 30 of the mobile position measurement device 1d except when measurement is being performed, and the reflecting element 4d can be installed on the robot T1 only when measurement is being performed, thereby reducing the risk of the surface of the reflecting element 4d becoming dirty. Note that the holder 30 may have a function of cleaning the reflecting element 4d while it is being held.

[0193] (Sixth embodiment) The sixth embodiment of the present invention will be described in detail below with reference to the drawings. In this embodiment, a mobile position measuring device controls the control system of a robot or machine tool, which is the object of measurement, based on the measurement results. The mobile position measuring device according to this embodiment is referred to as a mobile position measuring device 1e, and the position measuring device is referred to as a position measuring device 2e.

[0194] FIG. 18 is a diagram showing an example of how the mobile position measuring device 1e according to this embodiment controls a machine tool T2. The machine tool T2 controls a spindle T20 provided therein. The spindle T20 is provided inside the machine tool T2. The spindle T20 is a shaft in the machine tool T2 that has a rotating object attached to its end for rotation. Examples of rotating objects include blades and grinding wheels. The machine tool T2 is provided with a window that allows the inside of the machine tool T2 to be monitored from the outside. The spindle T20 is provided inside the machine tool T2. The reflective element is provided on the spindle T20. That is, the reflective element is disposed inside the machine tool T2. The reflective element is disposed, for example, on the upper part of the spindle T20.

[0195] The mobile position measuring device 1e transmits measurement light through a window of the machine tool T2 and irradiates it onto a reflecting element installed in the spindle T20. The mobile position measuring device 1e receives the reflected light from the reflecting element that has transmitted through the window of the machine tool T2. The window of the machine tool T2 preferably has a shape and is made of a material (refractive index, transmittance) that allows the measurement light and reflected light to pass sufficiently through and keeps the refraction of the measurement light and reflected light at or below a predetermined level.

[0196] The mobile position measuring device 1e communicates with the machine tool T2 via optical wireless communication. The mobile position measuring device 1e transmits measured position information to the machine tool T2 via optical wireless communication. In the mobile position measuring device 1e, the communication unit 25 includes a communication module for performing optical wireless communication.

[0197] The mobile position measuring device 1e may correct the measured position information based on the optical characteristics (refractive index, transmittance, etc.) of the window of the machine tool T2. Furthermore, the mobile position measuring device 1e may calculate the position information based on the optical characteristics of the window of the machine tool T2 in the process of calculating the position information. The mobile position measuring device 1e acquires information indicating the optical characteristics of the window of the machine tool T2 in advance by communicating with the machine tool T2.

[0198] The machine tool T2 uses the position information of the spindle T20 measured by the mobile position measuring device 1e for calibration for machining the spindle T20. When the machine tool T2 receives the position information from the mobile position measuring device 1e, it immediately performs calibration based on the position information. The machine tool T2 is equipped with a position measuring device that measures the position of the spindle T20. During calibration, the machine tool T2 outputs the position of the spindle T20 indicated by the position information received from the mobile position measuring device 1e to the position measuring device.

[0199] If the control unit 22 of the mobile position measuring device 1e and the control unit of the machine tool T2 are compatible, the mobile position measuring device 1e may control the machine tool T2 based on the measurement results. In this case, the mobile position measuring device 1e controls the spindle T20 instead of the machine tool T2. The mobile position measuring device 1e functions as a position measuring device provided outside the machine tool T2. As a position measuring device provided outside the machine tool T2, the mobile position measuring device 1e immediately calibrates the position of the spindle T20 during machining of the spindle T20.

[0200] Furthermore, when the mobile position measuring device 1e controls the machine tool T2, even if the machine tool T2 does not have the function to perform calibration based on highly accurate position information from the mobile position measuring device 1e, the spindle T20 can be calibrated with high precision based on the position information. The mobile position measuring device 1e may also control the position of the processing head of the laser processing device with high precision. Furthermore, the mobile position measuring device 1e may measure position information and / or control the machining head while the window of the machine tool T2 is open.

[0201] (Seventh embodiment) The seventh embodiment of the present invention will be described in detail below with reference to the drawings. In this embodiment, a case will be described in which a mobile position measuring device controls a host computer that controls factory facilities. The mobile position measurement device according to this embodiment is referred to as mobile position measurement device 1f, and the position measurement device is referred to as position measurement device 2f. Mobile position measurement device 1f includes, for example, the configuration of mobile position measurement device 1c and the configuration of mobile position measurement device 1d described above.

[0202] FIG. 19 is a diagram showing an example of how a mobile position measurement device 1f according to this embodiment controls multiple robots T3. The mobile position measurement device 1f and the multiple robots T3 are provided in a factory facility. The mobile position measurement device 1f can move freely within the factory facility. In the example shown in FIG. 19, seven robots T3, robot T3-1 to robot T3-7, are shown as the multiple robots T3. The factory facility is controlled by a host computer H1. The host computer H1 is an example of a control system for the multiple robots T3.

[0203] The mobile position measurement device 1f measures the position information of each of the multiple robots T3. The mobile position measurement device 1f performs measurements while sequentially switching between the robots T3 to be measured. The mobile position measurement device 1f moves through the factory facilities to a position where it can irradiate the measurement light onto the reflecting element installed on the robot T3 that is currently being measured among the multiple robots T3, and then stops and performs measurements.

[0204] The mobile position measurement device 1f measures the plurality of robots T3, for example, based on a predetermined order. The predetermined order is, for example, an order based on the positions at which the plurality of robots T3 are arranged within a factory facility. The predetermined order may be an order designated in advance by the host computer H1. The mobile position measurement device 1f may measure multiple robots T3 without following a predetermined order. For example, the mobile position measurement device 1f may capture an image of a 360-degree range around the mobile position measurement device 1f using the second imaging unit 28, and may determine the captured robot T3 as the measurement target based on the imaging results.

[0205] After measuring the position information, the mobile position measurement device 1f transmits the position information to the host computer H1 in sequence. The mobile position measurement device 1f may transmit the position information for each of the multiple robots T3 together to the host computer H1.

[0206] The mobile position measuring device 1f also transmits adjustment information for the robot T3 based on the position information to the host computer H1. The adjustment information includes a control signal for controlling the robot T3. The control signal includes, for example, a signal for controlling the position of an object to be manipulated by the robot T3 or an object to be processed by the robot T3. The control signal may also include both a signal for controlling the object to be manipulated by the robot T3 and a signal for controlling the position of an object to be processed by the robot T3. The control signal also includes a signal for controlling the position and movement of the multiple robots T3. These signals can be used to control each of the multiple robots T3 so as to avoid contact between the multiple robots T3.

[0207] As described above, in this embodiment, the mobile position measurement device 1f generates adjustment information for the first measurement target based on the position information for the first measurement target. Note that the mobile position measurement device 1f may also generate adjustment information for a second measurement target different from the first measurement target based on the position information for the first measurement target. The second measurement target is, for example, a measurement target located within a predetermined range from the position where the first measurement target is located. For example, the mobile position measuring device 1f controls the robot T3-2 or the robot T3-7 located within a predetermined range from the robot T3-1 based on the position information of the robot T3-1.

[0208] The mobile position measurement device 1f transmits the adjustment information to the host computer H1 via wireless communication. The wireless communication may be optical wireless communication. By using optical wireless communication, the mobile position measurement device 1f can communicate with the host computer H1 without interference from other wireless communication.

[0209] When the host computer H1 receives the adjustment information from the mobile position measurement device 1f, it controls the multiple robots T3 based on the received adjustment information. Control based on the adjustment information includes, as an example, control for indicating a target position of the workpiece to be processed by the robot T3. If the position of the workpiece indicated by the position information of the workpiece deviates from the expected position, the position information of the workpiece may be corrected by the amount of deviation based on the adjustment information. Alternatively, the position indicated by the position information of the workpiece may be set as an initial position, and the position of the workpiece may be calculated (converted) as a relative position from the initial position based on the adjustment information.

[0210] Therefore, the mobile position measurement device 1f can control the multiple robots T3 via the host computer H1 by transmitting adjustment information to the host computer H1. In other words, the mobile position measurement device 1f functions as a mobile control device that transmits commands from a higher level to the multiple robots T3 arranged in the factory.

[0211] The mobile position measuring device 1f transmits at least one of the position information and the adjustment information to the host computer H1. Alternatively, the mobile position measuring device 1f may transmit position information to the host computer H1, and the host computer H1 may generate adjustment information based on the position information received from the mobile position measuring device 1f. Furthermore, the mobile position measurement device 1f may directly control the plurality of robots T3 based on the adjustment information without going through the host computer H1.

[0212] Furthermore, the position measurement unit 20 provided in the position measurement device 2f acquires information about a coordinate system in the space in which the robot T3 is placed from the host computer H1. Alternatively, information about the coordinate system may be stored in a storage medium in the mobile position measurement device 1f, and the position measurement unit 20 may acquire the information about the coordinate system by reading it. The position measurement unit 20 generates coordinate position information of the robot T3 in the coordinate system based on the information about the coordinate system. The coordinate system is a reference coordinate system in the factory in which the robot T3 is placed. Therefore, the mobile position measurement device 1f can control multiple robots T3 based on a highly accurate coordinate system.

[0213] In the present embodiment, an example has been described in which one mobile position measuring device 1f that can move freely within the factory facility is provided, but the present invention is not limited to this. The mobile position measuring device 1f may be used in a position measuring system including a plurality of mobile position measuring devices 1f.

[0214] Furthermore, a factory facility may be equipped with multiple (N) mobile position measurement devices 1f. M robots may be controlled by the N mobile position measurement devices 1f. In this case, each of the multiple mobile position measurement devices 1f measures the position to one or more of the reflecting elements provided on each of the multiple robots. Here, the number N may be larger than the number M, the number N may be smaller than the number M, or the number N may be equal to the number M. The number N or the number M may be 1. In addition to a plurality of mobile position measuring devices 1f, a plurality of stationary position measuring devices 2 may be provided.

[0215] In the present embodiment, an example has been described in which the control system is a host computer H1 that manages and controls the entire factory facility, but the present invention is not limited to this. The control system may be a local server that manages and controls a portion of a factory facility, a server that manages and controls some of the multiple robots deployed in the factory facility, or a CPU (Central Processing Unit) that manages and controls one robot.

[0216] The position measurement device 2f may include a second imaging unit 28, similar to the position measurement device 2a according to the second embodiment described above. In this case, the position at which the mobile position measurement device 1f stops may be determined based on the imaging results of the second imaging unit 28. The mobile position measurement device 1f moves within the factory to a measurement position, which is a position for measuring the position of the measurement object. The control unit 22 captures an image of the measurement object in advance using the second imaging unit 28 before starting measurement, and determines the measurement position based on the imaging results of the second imaging unit 28. The mobile position measurement device 1f moves within the factory to the determined measurement position and stops at the measurement position. In this case, the control unit 22 may determine the measurement position while the mobile position measurement device 1f is stopped or while the mobile position measurement device 1f is moving before starting measurement.

[0217] Furthermore, for example, when the mobile position measurement device 1f determines that the position of the measurement target is far from the position of the mobile position measurement device 1f based on the imaging results of the second imaging unit 28, it first moves closer to the measurement target. At this time, the mobile position measurement device 1f moves while changing its own orientation so that it is easy to measure the measurement target. An orientation that is easy to measure the measurement target is, for example, an orientation in which the reflecting element 4 is visible from the front. The mobile position measurement device 1f may, for example, determine an image of the front of the reflecting element 4 based on image recognition, and determine the orientation in which the reflecting element 4 is visible from the front. The mobile position measurement device 1f may determine, as the orientation in which the reflecting element 4 is visible from the front, the imaging direction of the second imaging unit 28 in which the area of ​​the image of the reflecting element 4 in the image captured by the second imaging unit 28 is largest.

[0218] (Eighth embodiment) The eighth embodiment of the present invention will be described in detail below with reference to the drawings. In the above embodiments, the mobile position measuring device is described as measuring the position information of a robot or machine tool that processes a workpiece. In this example, the mobile position measuring device 1 is described as being used to measure the position information in a process of assembling parts.

[0219] Fig. 20 is a diagram showing an example of how the mobile position measuring device 1 according to this embodiment measures the position information of the optical scanner T4. The optical scanner T4 is a coordinate measuring machine (CMM) that measures the shape of an object in three dimensions using irradiated light. In Fig. 20, the optical scanner T4 measures the shape of an assembly part T5. The optical scanner T4 is arm-shaped, and irradiates the assembly part T5 with illumination light from the tip of the arm.

[0220] A reflective element 4 is installed at the tip of the arm of the optical scanner T4. The mobile position measurement device 1 measures the position information of the reflective element 4 installed in the optical scanner T4. The mobile position measurement device 1 transmits the measured position information to the control system of the optical scanner T4. The control system of the optical scanner T4 corrects the measurement results of the shape of the optical scanner T4 based on the position information measured by the mobile position measurement device 1.

[0221] It should be noted that the CMM that the mobile position measuring device 1 measures is not limited to the optical scanner T4. The mobile position measuring device 1 may also be used to assist in the measurement of a stationary CMM. In that case, the mobile position measuring device 1 may be installed in a part of the stationary CMM. For example, the mobile position measuring device 1 may be installed on the ceiling of the stationary CMM. The mobile position measuring device 1 installed on the ceiling measures the position information of a reflective element 4 installed in the measurement section of the stationary CMM.

[0222] (Ninth embodiment) The ninth embodiment of the present invention will be described in detail below with reference to the drawings. In this embodiment, a case will be described in which the mobile position measuring device 1 is used to measure position information in a process in which a large machine is assembled and processed in parallel. In this example, a case will be described in which the mobile position measurement device 1 provided in the mobile position measurement device 1 according to the first embodiment described above is used.

[0223] FIG. 21 is a diagram showing an example of how the mobile position measuring device 1 according to this embodiment measures position information during the assembly and machining process of the turbine T7. The optical scanner T6-1 is a CMM that performs three-dimensional measurement of the shape of the turbine T7. The optical processing machine T6-2 processes parts such as the turbine T7 blades by irradiating them with light. The cutting machine T6-3 processes parts such as the turbine T7 blades by cutting them. The optical scanner T6-1, the optical processing machine T6-2, and the cutting machine T6-3 are equipped with reflecting elements 4-1, 4-2, and 4-3, respectively.

[0224] The mobile position measuring device 1 measures position information for each of the reflecting elements 4-1, 4-2, and 4-3. The mobile position measuring device 1 transmits the measured position information to a control system that controls the optical scanner T6-1, the optical processing machine T6-2, and the cutting machine T6-3. Based on the position information measured by the mobile position measuring device 1, it is possible to measure the accuracy of assembly with high precision in processes in which the assembling and machining processes of parts of large machines such as turbines T7 are carried out in parallel.

[0225] In the above embodiment, the mobile position measurement device 1 is used in a machine assembly process, but the present invention is not limited to this. The mobile position measurement device 1 may also be used to measure position information in an overhaul process in which an assembled machine is disassembled, cleaned, and reassembled.

[0226] As described above, the position measurement device according to the embodiment (in the above embodiments, the mobile position measurement devices 1, 1a, 1b, 1c, 1d, 1e, and 1f) includes a movable moving device 3, a position measurement unit 20 including an irradiation unit that irradiates measurement light onto reflecting elements 4 and 4c arranged on a movable part of the robot, a light receiving unit that receives reflected light from the reflecting elements 4 and 4c, a position information acquisition unit that acquires position information of the reflecting elements 4 and 4c, and a moving unit (in the embodiment, the irradiation direction moving unit 201) that changes the irradiation direction of the measurement light, an imaging unit (in the embodiment, the first imaging unit 23), and a transmitting unit that transmits the position information acquired by the position measurement unit 20 or robot adjustment information based on the position information to the robot's control system. The moving device 3 moves at least one of the irradiating section, the light receiving section, the moving section (in the embodiment, the irradiation direction moving section 201), and the imaging section (in the embodiment, the first imaging section 23). The position measurement device (in the above embodiments, the mobile position measurement device 1, 1a, 1b, 1c, 1d, 1e, 1f) uses an imaging unit (in the embodiments, the first imaging unit 23) to image at least a part of the robot, or one or both of the reflecting elements 4 and 4c, and controls a moving unit (in the embodiments, the irradiation direction moving unit 201) based on the imaging results of the imaging unit (in the embodiments, the first imaging unit 23) so that measurement light is irradiated onto the reflecting elements 4 and 4c.

[0227] With this configuration, the position measurement device according to the embodiment (in the above embodiments, the mobile position measurement devices 1, 1a, 1b, 1c, 1d, 1e, 1f) can use an imaging unit (in the embodiment, the first imaging unit 23) to image at least a part of the robot, or one or both of the reflecting elements 4 and 4c, and based on the imaging results, can control a moving unit (in the embodiment, the irradiation direction moving unit 201) so that the measurement light is irradiated onto the reflecting elements 4 and 4c, thereby making it possible to measure the position of the robot with high accuracy when controlling the robot.

[0228] Furthermore, the measuring device according to the embodiment (in the above-described embodiments, the mobile position measuring devices 1, 1a, 1b, 1c, 1d, 1e, and 1f) includes a movable moving device 3, an irradiation unit provided on the moving device 3 that irradiates measuring light onto the reflecting elements 4 and 4c, a light receiving unit provided on the moving device 3 that receives reflected light of the measuring light from the reflecting elements 4 and 4c, and a measuring unit (in the embodiments, a signal processing unit of the optical comb interferometer 11) that acquires position information or distance information regarding the reflecting elements 4 and 4c based on the light receiving results by the light receiving unit.

[0229] With this configuration, the measuring device according to the embodiment (in the above-mentioned embodiments, the mobile position measuring devices 1, 1a, 1b, 1c, 1d, 1e, and 1f) can acquire position information or distance information regarding the reflecting elements 4 and 4c based on the light reception results from the light receiving unit, and therefore can measure the position of the measurement target or the distance from the measuring device (in the above-mentioned embodiments, the mobile position measuring devices 1, 1a, 1b, 1c, 1d, 1e, and 1f) with high accuracy.

[0230] Furthermore, the measuring device according to the embodiment (in the above embodiment, the mobile position measuring device 1c) comprises a movable moving device 3, a first irradiating unit provided on the moving device 3 and irradiating a first measuring light onto a first reflecting element (in the embodiment, reflecting element 4c) provided on the object to be measured, a reference irradiating unit (in the embodiment, reference measurement light irradiating unit 19) provided on the moving device 3 and irradiating a reference measuring light onto a reference reflecting element 5 relating to a reference position in the space in which the moving device 3 is arranged, and a measuring unit (in the embodiment, a signal processing unit of an optical comb interferometer 11) that acquires position information or distance information relating to the first reflecting element (in the embodiment, reflecting element 4c) relative to the reference position based on the first reflected light of the first measuring light from the first reflecting element (in the embodiment, reflecting element 4c) and the reference reflected light of the reference measuring light from the reference reflecting element 5.

[0231] With this configuration, the measuring device of the embodiment (in the above embodiment, the mobile position measuring device 1c) can acquire position information or distance information regarding the first reflecting element (in the embodiment, the reflecting element 4c) relative to the reference position based on the first reflected light of the first measurement light from the first reflecting element (in the embodiment, the reflecting element 4c) and the reference reflected light of the reference measurement light from the reference reflecting element 5, even if the reference position has not been acquired in advance.Therefore, even if the reference position has not been acquired in advance, the position of the measurement object or the distance from the measuring device (in the above embodiment, the mobile position measuring device 1c) can be measured with high accuracy.

[0232] Furthermore, the measuring device according to the embodiment (in the above embodiment, the mobile position measuring device 1c) includes a movable moving device 3, an irradiation unit provided on the moving device 3 that irradiates measurement light onto a reference reflecting element 5 related to a reference position in the space in which the moving device 3 is arranged, and irradiates measurement light onto a first reflecting element (in the embodiment, reflecting element 4c) provided on the object to be measured, and a measuring unit (in the embodiment, a signal processing unit of the optical comb interferometer 11) that acquires position information or distance information related to the first reflecting element (in the embodiment, reflecting element 4c) relative to the reference position based on the first reflected light of the measurement light from the first reflecting element (in the embodiment, reflecting element 4c) and the reference reflected light of the measurement light from the reference reflecting element 5.

[0233] With this configuration, the measurement device according to the embodiment (in the above embodiment, the mobile position measurement device 1c) can use the measurement light used to acquire position information or distance information regarding the first reflecting element (in the above embodiment, the reflecting element 4c) to measure the reference position, so that the position of the measurement object or the distance from the measurement device (in the above embodiment, the mobile position measurement device 1c) can be measured with high accuracy with a simple configuration without having to provide a separate reference irradiation unit for irradiating the reference measurement light, even if the reference position has not been acquired in advance.

[0234] Although an example in which each of the mobile position measurement devices 1, 1a, 1b, 1c, 1d, 1e, and 1f in the above-described embodiment includes an optical comb interferometer 11 has been described, the present invention is not limited to this. Each of the mobile position measurement devices 1, 1a, 1b, 1c, 1d, 1e, and 1f may measure the position of a measurement target based on a ranging method other than the optical comb method. The distance measurement method used by each of the mobile position measurement devices 1, 1a, 1b, 1c, 1d, 1e, and 1f may be, for example, a coaxial method or a non-coaxial method. Coaxial methods include, for example, a method that measures the TOF (Time of Flight) of an optical pulse, a method that measures the arrival time of modulated laser light, and a method that uses the coherence of laser light. Non-coaxial methods include, for example, triangulation, a stereo camera method, and a moire method.

[0235] The types of communication performed by the communication unit 25 provided in each of the mobile position measurement devices 1, 1a, 1b, 1c, 1d, 1e, and 1f in the above-described embodiments are not limited to those described in each embodiment. The communication unit 25 may perform various types of radio wave wireless communication, optical wireless communication, and wired communication. Various types of wireless communication include short-range wireless communication.

[0236] Note that a portion of the mobile position measurement devices 1, 1a, 1b, 1c, 1d, 1e, and 1f in the above-described embodiments, such as the control unit 22 and the calculation unit 26, may be implemented by a computer. In this case, a program for implementing this control function may be recorded on a computer-readable recording medium, and the program may be loaded and executed by a computer system. Note that the term "computer system" as used herein refers to a computer system built into the mobile position measurement devices 1, 1a, 1b, 1c, 1d, 1e, and 1f, including hardware such as an OS and peripheral devices. Furthermore, the term "computer-readable recording medium" refers to portable media such as flexible disks, optical magnetic disks, ROMs, and CD-ROMs, as well as storage devices such as hard disks built into computer systems. Furthermore, the term "computer-readable recording medium" may also include those that dynamically store programs for a short period of time, such as communication lines used when transmitting programs via networks such as the Internet or telephone lines, or those that store programs for a fixed period of time, such as volatile memory within the computer systems that serve as the server or client in such cases. Furthermore, the above program may be one that realizes part of the functions described above, or may be one that can realize the functions described above in combination with a program already recorded in the computer system. Furthermore, some or all of the mobile position measurement devices 1, 1a, 1b, 1c, 1d, 1e, and 1f in the above-described embodiments may be realized as integrated circuits such as LSI (Large Scale Integration). Each functional block of the mobile position measurement devices 1, 1a, 1b, 1c, 1d, 1e, and 1f may be individually implemented as a processor, or some or all of them may be integrated into a processor. Furthermore, the integrated circuit implementation method is not limited to LSI, and may be implemented using a dedicated circuit or a general-purpose processor. Furthermore, if an integrated circuit implementation technology that can replace LSI emerges due to advances in semiconductor technology, an integrated circuit based on that technology may be used.

[0237] One embodiment of the present invention has been described in detail above with reference to the drawings, but the specific configuration is not limited to that described above, and various design changes and the like are possible within the scope that does not deviate from the gist of the present invention.

[0238] Furthermore, it will be understood by those skilled in the art that the above-described embodiments and their modifications are specific examples of the following aspects. (Appendix 1) The measuring device includes a movable moving device, an irradiation unit provided on the moving device that irradiates measurement light onto a reflective element, a light receiving unit provided on the moving device that receives reflected light of the measurement light from the reflective element, and a measuring unit that acquires position information or distance information regarding the reflective element based on the light receiving result by the light receiving unit.

[0239] (Appendix 2) The above-mentioned measuring device further includes a first detection unit that receives light from the space in which the reflective element is arranged, and a moving unit that determines the position of the reflective element to be measured based on the detection result by the first detection unit and drives the irradiation unit so that the measurement light is irradiated onto the reflective element.

[0240] (Appendix 3) The above-mentioned measuring device further includes a second detection unit that receives light from the space in which the reflective element is arranged, and the moving unit determines the position of the reflective element to be measured based on the detection result by the second detection unit and moves the irradiation direction of the measurement light.

[0241] (Appendix 4) The above-mentioned measuring device further includes a third detection unit that receives light from a space in which the measurement object in which the reflective element is provided is placed, and a detection direction movement unit that moves the detection direction of the second detection unit based on the detection result by the third detection unit.

[0242] (Appendix 5) In the above-described measuring device, the first detection unit includes at least a photodiode array, the second detection unit includes a first imaging unit, and the third detection unit includes a second imaging unit having a wider imaging range than the first imaging unit.

[0243] (Appendix 6) In the above-mentioned measuring device, the reflecting element is disposed inside a robot or a machine tool.

[0244] (Appendix 7) In the above measurement device, the measurement light is an optical frequency comb.

[0245] (Appendix 8) The position measurement method includes a movable mobile device, a position measurement unit including an irradiation unit that irradiates measurement light onto a reflective element arranged on a movable part of the robot, a light receiving unit that receives the reflected light, a position information acquisition unit that acquires position information of the reflective element, and a mobile unit that changes the irradiation direction of the measurement light, an imaging unit, and a transmission unit that transmits the position information acquired by the position information acquisition unit or adjustment information of the robot based on the position information to a control system of the robot, and the mobile device is a position measurement method using a position measurement device that includes at least the irradiation unit, the light receiving unit, the mobile unit, and the imaging unit, and includes using the imaging unit to image at least a part of the robot, one or both of the reflective element, and controlling the mobile unit so that the measurement light is irradiated onto the reflective element based on the imaging result, irradiating the measurement light onto the reflective element with the irradiation unit, receiving the reflected light with the light receiving unit, and acquiring position information of the reflective element with the position information acquisition unit.

[0246] (Appendix 9) The measurement method is a measurement method using a measurement device that includes a movable moving device, an irradiation unit provided on the moving device and irradiating measurement light onto a reflective element, a light receiving unit provided on the moving device and receiving reflected light of the measurement light from the reflective element, and a measurement unit that acquires position information or distance information regarding the reflective element based on the light receiving result by the light receiving unit, and includes irradiating measurement light onto the reflective element by the irradiation unit, receiving reflected light of the measurement light from the reflective element by the light receiving unit, and acquiring position information or distance information regarding the reflective element by the measurement unit based on the light receiving result by the light receiving unit.

[0247] (Appendix 10) The measurement method uses a measurement device that includes a movable moving device, a first irradiation unit provided on the moving device and irradiating a first measurement light onto a first reflecting element provided on a measurement object, a reference irradiation unit provided on the moving device and irradiating a reference measurement light onto a reference reflecting element related to a reference position in a space in which the moving device is arranged, and a measurement unit that acquires position information or distance information regarding the first reflecting element relative to the reference position based on a first reflected light of the first measurement light from the first reflecting element and a reference reflected light of the reference measurement light from the reference reflecting element, and includes irradiating the first measurement light onto the first reflecting element by the first irradiation unit, irradiating the reference measurement light onto the reference reflecting element by the reference irradiation unit, and acquiring position information or distance information regarding the first reflecting element relative to the reference position based on the first reflected light of the first measurement light from the first reflecting element and the reference reflected light of the reference measurement light from the reference reflecting element by the measurement unit.

[0248] (Appendix 11) The measurement method uses a measurement device that includes a movable moving device, an irradiation unit that is provided on the moving device and irradiates measurement light onto a reference reflecting element related to a reference position in a space in which the moving device is arranged, and irradiates the measurement light onto a first reflecting element provided on a measurement object, and a measurement unit that acquires position information or distance information regarding the first reflecting element relative to the reference position based on a first reflected light of the measurement light from the first reflecting element and a reference reflected light of the measurement light from the reference reflecting element, and includes irradiating the measurement light onto the reference reflecting element by the irradiation unit and irradiating the measurement light onto the first reflecting element, and acquiring position information or distance information regarding the first reflecting element relative to the reference position based on the first reflected light of the measurement light from the first reflecting element and the reference reflected light of the measurement light from the reference reflecting element by the measurement unit. [Explanation of symbols]

[0249] 1, 1a, 1b, 1c, 1d, 1e, 1f...mobile position measuring device, 11...optical comb interferometer, 25...communication unit, 23...first imaging unit, 20...position measuring unit, 201...irradiation direction moving unit, 4, 4c...reflection element

Claims

1. a moving device that is movable relative to a robot having a movable part; a measuring device provided on the moving device and moving together with the moving device; Equipped with The measuring device is an irradiation unit that irradiates a measurement light onto a measurement target reflecting element provided on the movable unit of the robot, and irradiates a reference measurement light onto a reference reflecting element disposed at a reference position in a space in which the moving device is disposed; a measuring unit that acquires position information or distance information regarding the position of the measurement target reflecting element provided on the movable unit relative to the reference position in the space where the robot is located, based on the reflected light of the measurement light from the measurement target reflecting element and the reference reflected light of the reference measurement light from the reference reflecting element; A measurement system comprising:

2. Position information of the measurement target reflecting element relative to the reference position is generated based on a result of receiving the reflected light, which is the measurement light, from the irradiation unit via the measurement target reflecting element and a result of receiving the reference reflected light, which is the reference measurement light, from the irradiation unit via the reference reflecting element. The measurement system of claim 1 .

3. the reference reflective element comprises a first reference reflective element, a second reference reflective element, and a third reference reflective element; Position information of the measurement target reflecting element relative to the reference position is generated based on a first result of receiving the reference reflected light, which is the reference measurement light from the irradiation unit via the first reference reflecting element, a second result of receiving the reference reflected light, which is the reference measurement light from the irradiation unit via the second reference reflecting element, a third result of receiving the reference reflected light, which is the reference measurement light from the irradiation unit via the third reference reflecting element, and a fourth result of receiving the reflected light, which is the measurement light, from the irradiation unit via the measurement target reflecting element. The measurement system of claim 1 .

4. The measuring device includes a distance measurement unit that emits the measurement light and receives the reflected light of the measurement light from the measurement target reflection element to measure the distance to the measurement target reflection element, and an irradiation direction movement unit that changes the irradiation direction of the measurement light from the distance measurement unit. The measurement system according to any one of claims 1 to 3.

5. the irradiation direction moving unit includes a beam steering mirror that reflects the measurement light, The beam steering mirror is rotatable in both longitudinal and latitudinal directions. The measurement system of claim 4 .

6. a detection unit that receives light from a space in which the measurement target reflection element is disposed; a control unit that determines the position of the measurement target reflective element based on the detection result by the detection unit and controls the irradiation direction movement unit so that the measurement light is irradiated onto the measurement target reflective element; Equipped with The measurement system according to claim 4 or claim 5.

7. the detection unit includes a detection surface, The position of the light from the space in which the measurement target reflective element is arranged on the detection surface is measured. The measurement system of claim 6.

8. The detection unit includes a camera that captures an image of the measurement target reflecting element.

8. The measurement system according to claim 6 or claim 7.

9. the irradiation direction moving unit adjusts the irradiation direction so that the reference measurement light is directed toward a reference reflecting element related to a reference position; The measurement unit receives reference reflected light from the reference reflecting element, and generates position information of the measurement target reflecting element relative to the reference position based on the light reception result by the detection unit. A measurement system according to any one of claims 6 to 8.

10. The irradiation unit irradiates the measurement light onto the measurement target reflecting element after the moving device stops. A measurement system according to any one of claims 1 to 9.

11. The measurement unit acquires information about a coordinate system in a space in which the robot is placed, and generates coordinate position information of the robot in the coordinate system based on the information about the coordinate system. A measurement system according to any one of claims 1 to 10.

12. The coordinate system is a reference coordinate system within the factory where the robot is placed. The measurement system of claim 11.

13. The measurement unit generates information about the reference position after the moving device stops. A measurement system according to any one of claims 1 to 12.

14. The moving device includes an automated guided vehicle. A measurement system according to any one of claims 1 to 13.

15. A plurality of the measuring devices is provided.

15. A measurement system according to any one of claims 1 to 14.

16. Each of the plurality of measuring devices measures the position of one or more of the measurement target reflecting elements provided on each of the plurality of robots.

16. The measurement system of claim 15.

17. The measuring device is detachable from the moving device.

17. A measurement system according to any one of claims 1 to 16.

18. a measuring device provided on a moving device movable relative to a robot having a movable part, the measuring device being moved together with the moving device; measuring a reflective element to be measured provided on the movable part of the robot with measurement light from the measurement device; measuring a reference reflecting element disposed at a reference position in a space in which the moving device is disposed, with a reference measurement light from the measuring device; acquiring position information or distance information relating to the position of the measurement target reflecting element provided on the movable part relative to the reference position in a space where the robot is located, based on the reflected light of the measurement light from the measurement target reflecting element and the reference reflected light of the reference measurement light from the reference reflecting element; Measurement methods including:

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