Probe for three-dimensional coordinate measuring device, three-dimensional coordinate measuring device, three-dimensional coordinate measuring system, three-dimensional coordinate measuring method

Abstract

To provide a probe for three-dimensional coordinate measurement devices, a three-dimensional coordinate measurement device, a three-dimensional coordinate measurement system and a three-dimensional coordinate measurement method with which it is possible to calculate the coordinates of measurement points of a measurement object with high accuracy.SOLUTION: A probe 200 is used for three-dimensional coordinate measurement devices that calculate the coordinates of measurement points of a measurement object. The probe 200 has a plurality of markers eq to be imaged by an imaging part, which are held by a probe holding part 210. A stylus 211 that indicates a measurement point by contacting the measurement object is attached to the probe holding part 210. The stylus 211 has a predetermined positional relationship with respect to the plurality of measurement markers. The probe holding part 210 is floatably connected to a probe casing 220. Inside of the probe casing 220 is provided a magnetic sensor 270 that outputs a signal that corresponds to the amount of displacement of the probe holding part 210 relative to the probe casing 220.SELECTED DRAWING: Figure 13

Description

[Technical Field]

[0001] The present invention relates to a probe for a three-dimensional coordinate measuring device that is used in a three-dimensional coordinate measuring device that calculates the coordinates of a measurement point on a measurement object and that contacts the measurement object to indicate the measurement point, a three-dimensional coordinate measuring device, a three-dimensional coordinate measuring system, and a three-dimensional coordinate measuring method. [Background technology]

[0002] A contact-type three-dimensional coordinate measuring device uses a probe with a contact part. The contact part of the probe is brought into contact with the object to be measured, and the contact position between the object to be measured and the contact part is calculated. By calculating multiple positions on the object to be measured, the dimensions of a desired part of the object to be measured are measured.

[0003] The three-dimensional coordinate measuring device described in Patent Document 1 includes a mounting table, a probe, and an imaging unit. A contact part of the probe is brought into contact with a measurement object placed on the mounting table. Image data is generated by capturing images of multiple markers provided on the probe with the imaging unit. Coordinates of the contact position between the measurement object and the contact part are calculated based on the image data. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-190927 Summary of the Invention [Problem to be solved by the invention]

[0005] If the dimensions of each part of the probe change due to moisture absorption or changes in the temperature environment, the positional relationship between the multiple markers may also change. This change in the positional relationship between the multiple markers reduces the accuracy of calculating the coordinates of the contact position between the measurement object and the contact part. Therefore, in the above-mentioned three-dimensional coordinate measuring device, in order to reduce dimensional changes in each part of the probe due to moisture absorption and changes in the temperature environment, the multiple components that make up the probe are made of materials with low moisture absorption and a low linear expansion coefficient.

[0006] However, dimensional changes in each part of the probe can occur due to factors other than moisture absorption and changes in the temperature environment. For example, the above-mentioned probe is provided with a gripping part. The user operates the probe while holding the gripping part. Therefore, if the user presses the contact part strongly against the object to be measured, there is a high possibility that distortion will occur in each part of the probe. In this case, the positional relationship between the multiple markers and the contact part changes, reducing the accuracy of calculating the coordinates of the contact position between the object to be measured and the contact part.

[0007] An object of the present invention is to provide a probe for a three-dimensional coordinate measuring device, a three-dimensional coordinate measuring device, a three-dimensional coordinate measuring system, and a three-dimensional coordinate measuring method that enable the coordinates of a measurement point on a measurement object to be calculated with high accuracy. [Means for solving the problem]

[0008] (1) A probe for a three-dimensional coordinate measuring device according to a first aspect of the present invention is a probe used in a three-dimensional coordinate measuring device that calculates coordinates of a measurement point on a measurement object based on a plurality of measurement markers captured by an imaging unit, and includes a probe holding unit that holds the plurality of measurement markers, a stylus that has a contact unit that contacts the measurement object to indicate the measurement point and is attached to the probe holding unit in a predetermined positional relationship with the plurality of measurement markers, a probe casing that houses at least a part of the probe holding unit so that the plurality of measurement markers can be captured from the outside, and a probe housed in the probe casing and that is connected to the stylus. measurementan elastic body disposed between the probe casing and the probe holding part so that the probe holding part is displaced relative to the probe casing in response to contact with the object; and a signal corresponding to the amount of displacement of the probe holding part relative to the probe casing, which is received in the probe casing, and is transmitted to the stylus and measurement and a displacement sensor that outputs a signal related to contact with an object.

[0009] In this probe, the contact portion of the stylus is brought into contact with the measurement object to indicate a measurement point. The stylus and the probe holder are connected to each other in a predetermined positional relationship. The coordinates of the indicated measurement point are calculated based on image data obtained by capturing images of multiple markers on the probe holder and the positional relationship between the stylus and the probe holder. Therefore, it is desirable that the load applied to the measurement object from the contact portion of the stylus when indicating a measurement point be such that the positional relationship between the stylus and the probe holder does not change, i.e., such that excessive strain does not occur in the stylus and the probe holder.

[0010] According to the above configuration, the probe holder is movably connected to the probe casing via an elastic body. Therefore, when the contact portion of the stylus contacts the measurement point to be indicated on the measurement object, the stylus and the probe holder move relative to the probe casing before strain is generated in the stylus and the probe holder. At this time, a change in the output of the displacement sensor indicates a change in the positional relationship between the stylus and the probe holder and the probe casing. Therefore, based on the degree of change in the positional relationship between the stylus and the probe holder and the probe casing, the output of the displacement sensor can appropriately determine the timing of indicating the measurement point so as not to generate excessive strain in the stylus and the probe holder. As a result, it is possible to calculate the coordinates of the measurement point on the measurement object with high accuracy, regardless of the rigidity of the stylus and the probe holder.

[0011] (2) The probe for the three-dimensional coordinate measuring device may further include a probe control unit that outputs a trigger signal that allows the start of processing to calculate the coordinates of the indicated measurement point when a measurement point is indicated and a predetermined reference condition is satisfied for the displacement amount corresponding to the output signal of the displacement sensor.

[0012] In this case, the timing for specifying the measurement point is appropriately determined based on the output signal of the displacement sensor and the reference conditions, and the coordinates of the measurement point are calculated with high accuracy.

[0013] (3) The probe for a three-dimensional coordinate measuring device further includes a condition setting unit that sets a reference condition, wherein the reference condition is that the difference between the displacement amount corresponding to the signal output from the displacement sensor and the reference displacement amount is within a predetermined tolerance range. The condition setting unit may set the displacement amount corresponding to the signal output from the displacement sensor at a certain point in time as the reference displacement amount, and after a predetermined time has elapsed from the certain point in time, update the reference displacement amount with the displacement amount corresponding to the signal output from the displacement sensor.

[0014] In this case, the reference displacement amount is updated after a predetermined time has elapsed from a certain point in time, so that the timing for indicating the measurement point can be more appropriately determined based on the output signal of the displacement sensor and the reference conditions.

[0015] (4) The probe for a three-dimensional coordinate measuring device further includes a motion detection unit that detects the movement of the probe casing, and the probe control unit outputs a trigger signal when the amount of movement per unit time detected by the motion detection unit is less than or equal to a first threshold value, and may not output a trigger signal when the amount of movement per unit time detected by the motion detection unit is greater than the first threshold value.

[0016] In this case, if the movement of the probe casing changes significantly beyond the first threshold, a trigger signal is not output, which prevents, for example, the trigger signal from being erroneously output when the contact part is not in contact with the measurement point, and suppresses a decrease in the accuracy of calculating the coordinates of the measurement point.

[0017] (5) The probe for a three-dimensional coordinate measuring device may further include an attitude detection unit that detects the attitude of the probe casing, and the probe control unit may output a trigger signal when the amount of change in attitude per unit time detected by the attitude detection unit is less than or equal to a second threshold value, and may not output a trigger signal when the amount of change in attitude per unit time detected by the attitude detection unit is greater than the second threshold value.

[0018] In this case, if the attitude of the probe casing changes significantly beyond the second threshold value, no trigger signal is output, thereby preventing a decrease in the accuracy of calculation of the coordinates of the measurement point.

[0019] (6) The displacement sensor may include a magnetic sensor. The magnetic sensor makes it possible to detect the amount of displacement of the probe holding part relative to the probe casing regardless of the direction of the displacement. This reduces the number of parts in the probe. Furthermore, when a sensor that can detect displacement without contact, such as a magnetic sensor, is used, the probe holding part and the probe casing can be designed or manufactured independently, which reduces the difficulty of design and manufacturing.

[0020] (7) A gripping portion that can be held by a user may be connected to the probe casing. In this case, the user can easily indicate a desired portion of the measurement object as a measurement point while holding the gripping portion.

[0021] (8) A three-dimensional coordinate measuring device according to a second aspect of the present invention includes a probe for the above-mentioned three-dimensional coordinate measuring device, an imaging unit that images a plurality of measurement markers of the probe based on an output signal of a displacement sensor, and a calculation unit that calculates the coordinates of a measurement point indicated by a contact unit based on image data showing the images of the plurality of measurement markers imaged by the imaging unit.

[0022] The three-dimensional coordinate measuring device includes the above-described probe, which makes it possible to calculate the coordinates of a measurement point on a measurement object with high accuracy regardless of the rigidity of the stylus and the probe holder.

[0023] (9) A three-dimensional coordinate measuring system according to a third aspect of the present invention comprises a three-dimensional coordinate measuring device that calculates coordinates of a measurement point on a measurement object based on a plurality of measurement markers captured by an imaging unit; a probe including the plurality of measurement markers; a robot configured to be able to move the probe while holding it; and a robot control unit, wherein the probe has a probe holding unit that holds the plurality of measurement markers and a contact unit that indicates a measurement point by contacting the measurement object, a stylus attached to the probe holding unit in a predetermined positional relationship with the plurality of measurement markers; a probe casing that is held by the robot and contains at least a part of the probe holding unit so that the plurality of measurement markers can be captured from the outside; and a probe casing that is contained in the probe casing and contains the stylus and measurement an elastic body disposed between the probe casing and the probe holding part so that the probe holding part is displaced relative to the probe casing in response to contact with the object; and a signal corresponding to the amount of displacement of the probe holding part relative to the probe casing, which is received in the probe casing, and is transmitted to the stylus and measurement The three-dimensional coordinate measuring device comprises a displacement sensor that outputs a signal related to contact with an object, and a probe control unit that outputs a trigger signal that allows processing to begin for calculating the coordinates of the specified measurement point if a predetermined reference condition is satisfied for the amount of displacement corresponding to the output signal of the displacement sensor when a measurement point is specified, and the robot control unit controls the operation of the robot based on the output of the displacement sensor. The three-dimensional coordinate measuring device comprises an imaging unit that images multiple measurement markers of the probe when the trigger signal is output from the probe control unit, and a calculation unit that calculates the coordinates of the measurement point specified by the contact unit based on image data showing the image of the multiple measurement markers imaged by the imaging unit.

[0024] In this three-dimensional coordinate measuring system, the probe casing of the probe is held by a robot. The robot moves the probe casing, bringing the contact portion of the stylus into contact with the measurement object, thereby indicating a measurement point. The stylus and the probe holder are connected to each other in a predetermined positional relationship. The coordinates of the indicated measurement point are calculated based on image data obtained by capturing images of multiple markers on the probe holder and the positional relationship between the stylus and the probe holder. Therefore, it is desirable that the load applied to the measurement object from the contact portion of the stylus when indicating a measurement point be such that the positional relationship between the stylus and the probe holder does not change, i.e., such that excessive strain does not occur in the stylus and the probe holder.

[0025] According to the above-described probe configuration, the probe holder is connected to the probe casing by an elastic body so as to be able to move freely. Therefore, when the contact portion of the stylus comes into contact with the measurement point to be indicated on the measurement object, the stylus and the probe holder move relative to the probe casing before distortion occurs in the stylus and the probe holder. At this time, a change in the output of the displacement sensor indicates a change in the positional relationship between the stylus and the probe holder and the probe casing.

[0026] The robot operates based on the output of the displacement sensor. The output of the displacement sensor can be used to operate the robot without causing excessive strain on the stylus and probe holder based on the degree of change in the positional relationship between the stylus and probe holder and the probe casing. In addition, the timing for indicating the measurement point can be appropriately determined.

[0027] In the above-described three-dimensional coordinate measuring device, when the displacement amount corresponding to the output signal of the displacement sensor satisfies a predetermined reference condition, a trigger signal is output to calculate the coordinates of the designated measurement point. This causes images of the multiple measurement markers to be captured, and the coordinates of the measurement point are calculated based on the image data obtained by the image capture. In this way, the timing for designating the measurement point is appropriately determined based on the output signal of the displacement sensor and the reference condition, and the coordinates of the measurement point are calculated with high accuracy. As a result, it is possible to calculate the coordinates of the measurement point on the measurement object with high accuracy, regardless of the rigidity of the stylus and the probe holder.

[0028] (10) A three-dimensional coordinate measuring method according to a fourth aspect of the present invention is a three-dimensional coordinate measuring method for calculating coordinates of a measurement point on a measurement object using a probe, the probe having a probe holding part that holds a plurality of measurement markers and a contact part that indicates the measurement point by contacting the measurement object, a stylus attached to the probe holding part in a predetermined positional relationship with the plurality of measurement markers, a probe casing that houses at least a part of the probe holding part so that the plurality of measurement markers can be imaged from the outside, and a probe housed in the probe casing and connected to the stylus. measurement an elastic body disposed between the probe casing and the probe holding part so that the probe holding part is displaced relative to the probe casing in response to contact with the object; and a signal corresponding to the amount of displacement of the probe holding part relative to the probe casing, which is received in the probe casing, and is transmitted to the stylus and measurement The three-dimensional coordinate measuring method includes a step of outputting a trigger signal that allows starting a process for calculating the coordinates of the indicated measurement point when a measurement point is indicated and a predetermined reference condition is satisfied for the amount of displacement corresponding to the output signal of the displacement sensor, and a step of capturing an image of a plurality of measurement markers in response to the output of the trigger signal, and calculating the coordinates of the measurement point indicated by the contact unit based on image data representing the captured images of the plurality of measurement markers.

[0029] In the above-described probe, the contact portion of the stylus is brought into contact with the measurement object to indicate a measurement point. The stylus and the probe holder are connected to each other in a predetermined positional relationship. The coordinates of the indicated measurement point are calculated based on image data obtained by capturing images of multiple markers on the probe holder and the positional relationship between the stylus and the probe holder. Therefore, it is desirable that the load applied to the measurement object from the contact portion of the stylus when indicating a measurement point be such that the positional relationship between the stylus and the probe holder does not change, i.e., such that excessive strain does not occur in the stylus and the probe holder.

[0030] The probe holder is connected to the probe casing via an elastic body so as to be able to move freely. Therefore, when the contact portion of the stylus comes into contact with the measurement point to be indicated on the measurement object, the stylus and the probe holder move relative to the probe casing before strain is generated in the stylus and the probe holder. At this time, a change in the output of the displacement sensor indicates a change in the positional relationship between the stylus and the probe holder and the probe casing. Therefore, the output of the displacement sensor can be used to appropriately determine the timing of indicating the measurement point based on the degree of change in the positional relationship between the stylus and the probe holder and the probe casing, so as to prevent excessive strain from being generated in the stylus and the probe holder.

[0031] In the above-described three-dimensional coordinate measurement method, when a displacement amount corresponding to an output signal of the displacement sensor satisfies a predetermined reference condition, a trigger signal is output to calculate the coordinates of the designated measurement point. In response to the output of the trigger signal, images of the multiple measurement markers are captured, and the coordinates of the measurement point are calculated based on the image data obtained by the image capture. In this way, the timing for designating the measurement point is appropriately determined based on the output signal of the displacement sensor and the reference condition, and the coordinates of the measurement point are calculated with high accuracy. As a result, it is possible to calculate the coordinates of the measurement point on the measurement object with high accuracy, regardless of the rigidity of the stylus and the probe holder.

[0032] (11) The three-dimensional coordinate measurement method may further include a step of setting a reference condition, wherein the reference condition is that the difference between the displacement amount corresponding to the signal output from the displacement sensor and the reference displacement amount is within a predetermined tolerance range, and the step of setting the reference condition may include setting the displacement amount corresponding to the signal output from the displacement sensor at a certain point in time as the reference displacement amount, and updating the reference displacement amount with the displacement amount corresponding to the signal output from the displacement sensor after a predetermined time has elapsed from the certain point in time.

[0033] In this case, the reference displacement amount is updated after a predetermined time has elapsed from a certain point in time, so that the timing for indicating the measurement point can be more appropriately determined based on the output signal of the displacement sensor and the reference conditions.

[0034] (12) The three-dimensional coordinate measurement method may further include a step of detecting movement of the probe casing, and the step of outputting a trigger signal may be performed when the amount of movement per unit time detected by the step of detecting movement is equal to or less than a first threshold value, and may not be performed when the amount of movement per unit time detected by the step of detecting movement is greater than the first threshold value.

[0035] In this case, if the movement of the probe casing changes significantly beyond the first threshold, a trigger signal is not output, which prevents, for example, the trigger signal from being erroneously output when the contact part is not in contact with the measurement point, and suppresses a decrease in the accuracy of calculating the coordinates of the measurement point.

[0036] (13) The three-dimensional coordinate measurement method may further include a step of detecting the attitude of the probe casing, and the step of outputting a trigger signal may be performed when the amount of change in attitude per unit time detected by the attitude detecting step is less than or equal to a second threshold value, and may not be performed when the amount of change in attitude per unit time detected by the attitude detecting step is greater than the second threshold value.

[0037] In this case, if the attitude of the probe casing changes significantly beyond the second threshold value, no trigger signal is output, thereby preventing a decrease in the accuracy of calculation of the coordinates of the measurement point. [Effects of the Invention]

[0038] According to the present invention, it is possible to calculate the coordinates of a measurement point on a measurement object with high accuracy. [Brief explanation of the drawings]

[0039] [Figure 1] FIG. 1 is a schematic diagram showing an example of use of a three-dimensional coordinate measuring device according to a first embodiment. [Figure 2] FIG. 4 is a schematic diagram showing another example of use of the three-dimensional coordinate measuring device according to the first embodiment. [Figure 3] FIG. 2 is a block diagram showing the configuration of an imaging head and a processing device. [Figure 4] FIG. 2 is a front view of the imaging head. [Figure 5] FIG. [Figure 6] FIG. 2 is a side view of one side of the imaging head. [Figure 7] FIG. 2 is a plan view of the imaging head. [Figure 8] FIG. 2 is a perspective view of the appearance of the imaging head with the casing removed. [Figure 9] 5 is a schematic cross-sectional view of the imaging head taken along line AA in FIG. 4. [Figure 10] 10(a) is a schematic vertical cross-sectional view of the reference member of FIG. 9, and FIG. 10(b) is a bottom view of the reference member. [Figure 11] 1A and 1B are bottom and side views of the head bottom portion. [Figure 12] 2A and 2B are a plan view and a side view of the head base of FIG. 1. [Figure 13] FIG. 2 is a block diagram showing the basic configuration of a probe. [Figure 14] FIG. 2 is an external perspective view of the probe as viewed in one direction. [Figure 15] FIG. 10 is an external perspective view of the probe as viewed from another direction. [Figure 16] 10 is an external perspective view of the probe with the gripping portion in a second state, viewed from one direction. FIG. [Figure 17] 10 is an external perspective view of the probe with the gripping portion in the second state, viewed from another direction. FIG. [Figure 18] 1 is a schematic diagram showing a state in which a user measures an object to be measured using a probe whose grip portion is in a first state. FIG. [Figure 19] 10 is a schematic diagram showing a state in which a user measures an object to be measured using a probe whose grip portion is in a second state. FIG. [Figure 20] FIG. 2 is a partially cutaway cross-sectional view of the probe showing the internal structure of the main body. [Figure 21] FIG. 2 is an exploded perspective view of the probe for illustrating an outline of the internal structure of the main body. [Figure 22] 4 is a flowchart showing the flow of measurement processing by the main body control circuit of FIG. 3. [Figure 23] 10 is a flowchart showing the flow of a measurement point coordinate calculation process. [Figure 24] 14 is a flowchart showing the flow of a contact trigger output process by the probe control unit of FIG. 13. [Figure 25] 4 is a flowchart showing the flow of tracking processing by the main body control circuit of FIG. 3. [Figure 26] FIG. 10 is a diagram showing an example of a measurement screen displayed on the main body display unit at the initial stage of measurement of the measurement object. [Figure 27] FIG. 10 is a diagram showing an example of a measurement screen when a screen operation function is activated during measurement of a measurement object. [Figure 28] FIG. 10 is a diagram showing an example of a measurement screen on which an instruction mode selection window is superimposed. [Figure 29] FIG. 10 is a diagram showing an example of a display on a measurement screen when it becomes possible to select geometric elements and measurement items using a probe. [Figure 30] FIG. 10 is a diagram showing an example of a measurement screen when a plurality of measurement points are designated after a geometric element is selected. [Figure 31] FIG. 10 is a diagram showing an example of a measurement screen after a measurement item is selected. [Figure 32] FIG. 10 is a diagram showing an example of a measurement screen when a captured image is displayed in a measurement state display area. [Figure 33] FIG. 2 is a block diagram showing the functional configuration of a main body control circuit related to operations for measurement. [Figure 34] FIG. 10 is a schematic diagram showing an example of the configuration of a three-dimensional coordinate measuring system according to a second embodiment. [Figure 35] FIG. 35 is a block diagram showing the basic configuration of the probe of FIG. 34. [Figure 36] FIG. 35 is a block diagram showing the configuration of the imaging head and processing device of FIG. 34. DETAILED DESCRIPTION OF THE INVENTION

[0040] 1. First embodiment [1] Basic configuration and usage examples of a three-dimensional coordinate measuring device 1 is a schematic diagram showing an example of use of a three-dimensional coordinate measuring device according to a first embodiment. As shown in FIG. 1, a three-dimensional coordinate measuring device 1 according to this embodiment is mainly composed of an imaging head 100, a probe 200, a processing device 300, and a holding unit 800.

[0041] The holding unit 800 includes a mounting unit 810, a mounting table 820, and a head base 830. The mounting unit 810 has a flat plate shape extending in one direction and is mounted on a mounting surface such as the top surface of a table. The mounting unit 810 is made of aluminum, iron, or an alloy thereof, and has high rigidity. A mounting table 820 is provided at one end of the mounting unit 810. In this example, the mounting table 820 is an optical surface plate having a substantially rectangular shape and is connected to the top surface of the mounting unit 810 so that its short side is parallel to the longitudinal direction of the mounting unit 810 (the direction in which the mounting unit 810 extends). The length L1 of the long side of the mounting table 820 is, for example, approximately 450 mm, and the length L2 of the short side of the mounting table 820 is, for example, approximately 300 mm. The mounting table 820 may have a square, circular, or elliptical shape. The measurement target S is mounted on the mounting table 820.

[0042] A head base 830 is provided at the other end of the installation unit 810. The head base 830 in this example is configured to allow a bottom portion 101 of the imaging head 100 (hereinafter referred to as the head bottom portion) to be attached and detached. With the head bottom portion 101 attached to the head base 830, the imaging head 100 is fixed to the installation unit 810 and the mounting base 820. On the other hand, with the head bottom portion 101 detached from the head base 830, the imaging head 100 is separated from the installation unit 810 and the mounting base 820, as shown by the dotted white arrow in FIG. 1 .

[0043] Probe 200 is configured to be portable by the user. Probe 200 is provided with contact portion 211a. To indicate a measurement point, the user brings contact portion 211a of probe 200 into contact with a desired portion of measurement object S. As a result, contact portion 211a indicates the measurement point, and the portion of measurement object S that is in contact with contact portion 211a is indicated as the measurement point.

[0044] A movable camera 120 is provided inside the imaging head 100. The movable camera 120 captures images of a plurality of markers eq (described later, FIG. 14, etc.) provided on the probe 200. The imaging head 100 is also connected to a processing device 300 via a cable CA. The processing device 300 is, for example, a personal computer, and is connected to a main body display unit 310 and a main body operation unit 320. The processing device 300 calculates coordinates of measurement points on the measurement object S based on image data (hereinafter referred to as measurement image data) obtained by the movable camera 120 capturing an image of the probe 200 and reference image data (described later). By calculating the coordinates of one or more measurement points on the measurement object S, physical quantities of the measurement object S are measured based on the calculation results.

[0045] When the user moves probe 200, the orientation of the imaging field of movable camera 120 follows the movement of probe 200, as indicated by thick solid arrows a1 and a2 in FIG. 1 . That is, the orientation of movable camera 120 changes as probe 200 moves so that probe 200 is positioned within the imaging field of movable camera 120. Movable camera 120 according to this embodiment has a depth of field that covers at least the space above mounting table 820 when its imaging field of view is directed toward mounting table 820. Therefore, three-dimensional coordinate measuring device 1 has a wide measurable area that includes the space above mounting table 820. This expands the range of positions and orientations of probe 200 required to measure the physical quantities of measurement target S.

[0046] As described above, according to the three-dimensional coordinate measuring device 1 of this embodiment, it is possible to measure the physical quantities of the measurement object S placed on the mounting table 820 with the imaging head 100 attached to the head pedestal 830. On the other hand, if it were possible to measure the physical quantities of the measurement object S that is not placed on the mounting table 820, the usability of the three-dimensional coordinate measuring device 1 would be improved. Therefore, in addition to the above configuration, the three-dimensional coordinate measuring device 1 of this embodiment further includes a reference stand for fixing the imaging head 100 to an installation surface such as a floor. An example of using the three-dimensional coordinate measuring device 1 using the reference stand will be described.

[0047] FIG. 2 is a schematic diagram showing another example of use of the three-dimensional coordinate measuring device 1 according to the first embodiment. As shown in FIG. 2, the three-dimensional coordinate measuring device 1 further includes a reference stand 900. The reference stand 900 is a tripod and is composed of a head base 911 and legs 912. The head base 911 is provided at the upper end of the legs 912 and is configured to allow the head bottom 101 of the imaging head 100 to be attached and detached, similar to the head base 830 of the holder 800 in FIG. 1. In this example, the imaging head 100 detached from the holder 800 in FIG. 1 is attached to the head base 911 of the reference stand 900.

[0048] Using the reference stand 900, the user U can fix the imaging head 100, for example, to the floor surface so that the measurement target S set in the processing machine 9 is located within the depth of field of the movable camera 120. The processing machine 9 is a processing device such as a lathe, milling machine, or electric discharge machine. Alternatively, the user U can fix the imaging head 100, for example, to the floor surface so that the measurement target S placed on the floor is located within the depth of field of the movable camera 120. Therefore, the user U can measure the physical quantity of the measurement target S that is not placed on the mounting table 820 of FIG. 1 by contacting the contact portion 211a of the probe 200 he / she carries with him / her to a desired portion of the measurement target S. Note that in this example, when the user U moves while carrying the probe 200, the orientation of the imaging field of the movable camera 120 follows the movement of the probe 200, as in the example of FIG. 1. The configuration of each part of the three-dimensional coordinate measuring device 1 will be described in detail below.

[0049] [2] Configuration of the imaging head 100 and the processing device 300 Fig. 3 is a block diagram showing the configuration of the imaging head 100 and the processing device 300. Fig. 4 is a front view of the imaging head 100, and Fig. 5 is a rear view of the imaging head 100. Fig. 6 is a side view of one side of the imaging head 100, and Fig. 7 is a plan view of the imaging head 100. As shown in Figs. 4 to 7, the imaging head 100 has a configuration in which multiple components are housed in a casing 90. Fig. 8 is an external perspective view of the imaging head 100 with the casing 90 removed, and Fig. 9 is a schematic cross-sectional view of the imaging head 100 taken along line AA in Fig. 4.

[0050] (1) Imaging head 100 First, we will explain the configuration of imaging head 100. As shown in Fig. 3, imaging head 100 includes, as electrical components, reference camera 110, movable camera 120, marker drive circuit 130, rotation drive circuit 140, head control circuit 150, wireless communication circuit 160, communication circuit 170, overhead camera 180, and reference member 190. These components are housed in casing 90 shown in Figs. 4 to 7, supported by any of fixed connecting part 20, support member 30, and movable member 40, which are indicated by two-dot chain lines in Fig. 3.

[0051] Each of base camera 110, movable camera 120, and overhead camera 180 includes a CMOS (complementary metal-oxide semiconductor) image sensor capable of detecting infrared light as an imaging element. Base camera 110, movable camera 120, and overhead camera 180 are each provided with substrates 111, 121, and 181 on which CMOS image sensors are mounted. In FIG. 3, the multiple circuits (140, 150, 160, and 170) enclosed by thick dotted lines generate more heat during operation than the various elements mounted on substrates 111, 121, and 181 of base camera 110, movable camera 120, and overhead camera 180. In the following description, the one or more substrates on which rotation drive circuit 140, head control circuit 150, wireless communication circuit 160, and communication circuit 170 are mounted will be collectively referred to as heat-generating substrate GS, as appropriate.

[0052] 4 to 7, the casing 90 is made up of a lower casing 91, an upper casing 92, and a base casing 93. The lower casing 91 has a generally cylindrical shape, is fixed to the head bottom 101 of the imaging head 100, and extends a certain distance upward from the head bottom 101. The upper casing 92 is provided above the lower casing 91. The upper casing 92 has a generally bell shape, and is provided rotatably in a horizontal plane together with a support member 30 (FIG. 8) described below.

[0053] 4, a rectangular opening 92S is formed in a part of the upper casing 92, extending in the vertical direction from near the upper end to the center of the upper casing 92. The rectangular opening 92S guides the imaging field of view of the movable camera 120 to the outside of the casing 90. Furthermore, the upper casing 92 is formed with two intake sections HA1 on both sides of the rectangular opening 92S and near the lower end of the upper casing 92.

[0054] An overhead camera window 91W is formed in part of the outer circumferential surface of the lower casing 91. The overhead camera window 91W guides the imaging field of view of the overhead camera 180 to the outside of the casing 90. In the following description, the one direction in which the overhead camera window 91W faces is referred to as the front of the imaging head 100. Additionally, the direction opposite to the one direction relative to the imaging head 100 is referred to as the rear of the imaging head 100. In addition to the overhead camera window 91W, two air intake sections LA1 are formed near the front and bottom end of the lower casing 91.

[0055] 5 and 6, a board casing 93 is connected to a rearward-facing portion (rear half) of the outer peripheral surface of the lower casing 91. The board casing 93 includes a first housing portion 93a and a second housing portion 93b. The first housing portion 93a has a box shape that extends from the rear half of the lower casing 91 toward the rear of the imaging head 100. The second housing portion 93b is formed so as to protrude upward from a portion of the upper surface of the first housing portion 93a.

[0056] 9, the internal space of the first housing portion 93a and the internal space of the second housing portion 93b in the base casing 93 are in communication with each other. The internal space of the first housing portion 93a and the internal space of the lower casing 91 are also in communication with each other. On the other hand, the internal space of the lower casing 91 and the internal space of the upper casing 92 are separated by an upper fixing plate 22, which will be described later, and therefore do not communicate with each other.

[0057] 5, 6, and 9, a heat-generating substrate GS is accommodated from the bottom of the first accommodation portion 93a to the top of the second accommodation portion 93b inside the substrate casing 93. On the other hand, a plurality of substrates (substrates 111, 121, 181, etc.) that have lower heat generation properties than the heat-generating substrate GS are accommodated in the lower casing 91 or the upper casing 92.

[0058] As shown in FIG. 5, an exhaust section LA2 is formed at the lower rear end of the first housing section 93a of the board casing 93. An exhaust fan LF is provided inside the first housing section 93a adjacent to the exhaust section LA2. The exhaust fan LF exhausts the atmosphere inside the lower casing 91 and the board casing 93 to the outside of the imaging head 100 through the exhaust section LA2. At this time, air outside the imaging head 100 flows into the inside of the lower casing 91 through the two intake sections LA1 shown in FIG. 4. This generates a smooth airflow from the front of the imaging head 100 through the internal spaces of the lower casing 91 and the board casing 93 toward the rear of the imaging head 100, as indicated by multiple white arrows f1 in FIG. 6. In this case, the heat-generating substrate GS housed in the board casing 93 is located downstream of the lower casing 91 in the air flow inside the lower casing 91 and the board casing 93. This reduces the amount of heat generated by the heat-generating substrate GS entering the internal space of the lower casing 91. Furthermore, since the heat generated by the heat-generating substrate GS does not remain in the internal space of the lower casing 91, the heat generated by the heat-generating substrate GS is prevented from being transmitted to the internal space of the upper casing 92 through the internal space of the lower casing 91.

[0059] As shown in FIG. 7, an exhaust section HA2 is formed at the top of the upper casing 92 on the opposite side of the rectangular opening 92S with respect to the center of the upper casing 92 in a plan view. An exhaust fan HF is provided inside the upper casing 92 adjacent to the exhaust section HA2. The exhaust fan HF exhausts the atmosphere inside the lower casing 91 to the outside of the imaging head 100 through the exhaust section HA2. At this time, air outside the imaging head 100 flows into the interior of the upper casing 92 from the two intake sections HA1 in FIG. 4. This generates a smooth air flow that flows diagonally upward from the bottom of the upper casing 92 through the internal space of the upper casing 92 from the two intake sections HA1 of the lower casing 91, as indicated by multiple white arrows f2 in FIG. 6. In this case, as described below, heat generated on the board 43 on which the movable camera 120 or marker driving circuit 130 housed in the upper casing 92 is mounted flows smoothly from bottom to top within the lower casing 91 and is discharged to the outside of the lower casing 91.

[0060] As shown in FIGS. 8 and 9 , the fixed connecting part 20 includes a lower fixed plate 21, an upper fixed plate 22, a plurality of (for example, four) support columns 23, and a hollow support shaft 24. The lower fixed plate 21 has a disk shape and is fixed to the upper surface of the head bottom part 101 using screws. The upper fixed plate 22 is provided above the lower fixed plate 21 via a plurality of support columns 23. The upper fixed plate 22 has a disk shape similar to the lower fixed plate 21. A circular opening is formed in the center of the upper fixed plate 22. The hollow support shaft 24 is fixed to the upper surface of the upper fixed plate 22 using screws so as to surround the opening in the center of the upper fixed plate 22. The lower casing 91 is attached to one of the members constituting the fixed connecting part 20.

[0061] In the fixed connecting portion 20, an overhead camera 180 is provided in the space between the lower fixed plate 21 and the upper fixed plate 22, along with various substrates (substrates with lower heat generation than the heat-generating substrate GS) excluding the heat-generating substrate GS. Furthermore, as shown in FIG. 9 , a reference camera 110 is provided on the lower fixed plate 21 so as to extend from approximately the center of the lower casing 91 through the opening in the upper fixed plate 22 to the inside of the hollow support shaft 24. In this state, the imaging field of the reference camera 110 faces upward. In this embodiment, the optical axis 110c of the optical system of the reference camera 110 coincides with the central axis of the hollow support shaft 24.

[0062] In addition to the various substrates and reference camera 110 described above, a horizontal rotation mechanism 141 is provided on lower fixed plate 21 and upper fixed plate 22 to rotate support member 30 (described later) around the central axis of hollow support shaft 24 (to rotate within a plane parallel to the top surface of head bottom 101). Horizontal rotation mechanism 141 includes, for example, a motor and various power transmission members.

[0063] As shown in FIG. 8, a support member 30 is provided on the hollow support shaft 24 of the fixed connecting part 20. The support member 30 includes a rotating base 31 and a pair of support frames 32, 33. The rotating base 31 has an opening in the center and is attached to the upper end of the hollow support shaft 24 via a cross roller bearing CB (FIG. 9) so that the support member 30 can rotate around the central axis of the hollow support shaft 24. An upper casing 92 is attached to one of the members constituting the support member 30. When the support member 30 rotates with respect to the hollow support shaft 24, the upper casing 92 rotates together with the support member 30 relative to the lower casing 91 (see the thick dashed arrow in FIG. 7).

[0064] The pair of support frames 32, 33 are formed to face each other and extend upward from one side and the other side of the rotating base 31. A movable member 40 is provided between the pair of support frames 32, 33 at a position spaced a predetermined distance from the rotating base 31.

[0065] The movable member 40 is supported by the support frames 32, 33 so as to be rotatable (tiltable relative to a horizontal plane) around a rotation axis 30c that passes through opposing portions of the pair of support frames 32, 33. In this embodiment, the rotation axis 30c is perpendicular to the optical axis 110c of the reference camera 110 (FIG. 9) and the central axis of the hollow support shaft 24.

[0066] A tilt rotation mechanism 143 is attached near the upper end of the support frame 33 on the opposite side of the movable member 40 and located on the rotation axis 30c. The tilt rotation mechanism 143 includes, for example, a motor and various power transmission members. The tilt rotation mechanism 143 rotates the movable member 40 around the rotation axis 30c.

[0067] Movable member 40 is formed in the shape of a flat, substantially square cylinder, and has upper surface 41 and lower surface 42. Movable camera 120 and various boards associated with movable camera 120 are fixed on movable member 40. In this state, optical axis 120c (FIG. 9) of the optical system of movable camera 120 is parallel to upper surface 41 of movable member 40. A board 43 on which marker drive circuit 130 (FIG. 3) is mounted is provided on the upper end of movable member 40 so as to cover the opening in the center thereof.

[0068] As shown in Fig. 9, a reference member 190 having a plurality of markers ep (Fig. 3) is provided inside the movable member 40. Fig. 10(a) is a schematic vertical cross-sectional view of the reference member 190 in Fig. 9, and Fig. 10(b) is a bottom view of the reference member 190.

[0069] 10(a) and 10(b), the reference member 190 includes a light-emitting substrate 191, a diffusion plate 192, a glass plate 193, and a diffuse reflection sheet 195. The light-emitting substrate 191, the diffusion plate 192, and the glass plate 193 are layered in this order from top to bottom. The diffuse reflection sheet 195 is provided so as to surround the outer periphery of the layered structure.

[0070] A plurality of light-emitting elements L are mounted all over the bottom surface of the light-emitting substrate 191. Each light-emitting element L is, for example, an infrared LED (light-emitting diode). A marker driving circuit 130 drives the plurality of light-emitting elements L on the light-emitting substrate 191. This causes the plurality of light-emitting elements L to emit light.

[0071] The diffusion plate 192 is a plate member made of, for example, resin, and transmits downward while diffusing the light generated from the plurality of light-emitting elements L. The diffusion reflection sheet 195 is a strip-shaped sheet member made of, for example, resin, and reflects inward the light emitted from the plurality of light-emitting elements L and directed to the side (outward) of the reference member 190.

[0072] Glass plate 193 is a plate member made of, for example, quartz glass or soda glass. A mask 194 having a plurality of circular openings is provided on the lower surface of glass plate 193. Mask 194 is, for example, a chrome mask formed on the lower surface of glass plate 193 by sputtering or vapor deposition.

[0073] With the above configuration, light emitted from the plurality of light-emitting elements L and diffused by the diffusion plate 192 and the diffuse reflection sheet 195 is emitted below the reference member 190 through the plurality of circular openings in the glass plate 193 and the mask 194. In this way, a plurality of self-luminous markers ep corresponding to the plurality of circular openings are formed.

[0074] In this embodiment, as shown in FIG. 10(b), the multiple markers ep are arranged at equal intervals in a matrix on the lower surface (plane) of the reference member 190. Of the multiple markers ep, a marker ep located in the center and another marker ep spaced a predetermined distance from the central marker ep are provided with identification marks (dots in this example) to distinguish them from the other markers ep. These identification marks are formed by part of the mask 194. In the following description, when distinguishing between two markers ep with identification marks provided among the multiple markers ep, the central marker ep including the identification mark will be referred to as the first marker ep1. The other marker ep including the identification mark will be referred to as the second marker ep2.

[0075] In the above configuration, the reference member 190 is attached to the movable member 40 so that the downward-facing markers ep are located within the imaging field of view of the base camera 110. Furthermore, the reference member 190 is attached to the movable member 40 so that the first marker ep1 is located on the optical axis 110c when the upper surface 41 and the lower surface 42 of the movable member 40 are perpendicular to the direction of the optical axis 110c of the base camera 110.

[0076] When the support member 30 rotates on the fixed connection part 20 and when the movable member 40 rotates around the rotation axis 30c, the image of the multiple markers ep obtained by the base camera 110 capturing an image of the reference member 190 changes. Therefore, for example, assume that the image obtained when the support member 30 and the movable member 40 are in a predetermined reference position changes. In this case, the amount by which the support member 30 has rotated from the reference position can be determined based on the positional relationship between the first marker ep1 and the second marker ep2 in the image. Furthermore, the amount by which the movable member 40 has rotated from the reference position can be determined based on the distortion occurring in the arrangement of the multiple markers ep in the image.

[0077] As described above, movable camera 120 and reference member 190 are integrally fixed to movable member 40. This makes it possible to calculate the position and orientation of movable camera 120 relative to reference camera 110 based on image data (hereinafter referred to as reference image data) obtained by reference camera 110 capturing images of multiple markers ep on reference member 190.

[0078] A bellows 50 is provided between the movable member 40 and the rotating base 31, which optically and spatially isolates the imaging space rs (Figure 9) including the imaging field of view of the reference camera 110 from the reference camera 110 to the reference member 190 from the outside of the imaging space rs.

[0079] In this example, the upper end of bellows 50 is joined to lower surface 42 of movable member 40, and the lower end of bellows 50 is joined to the upper surface of rotating base 31. As a result, when support member 30 rotates in the horizontal plane, bellows 50 also rotates together with support member 30.

[0080] Also, bellows 50 in this example has a substantially square cylindrical shape, and is configured to be able to maintain an optically and spatially blocked state of imaging space rs by deforming in accordance with the rotation of movable member 40 when tilt rotation mechanism 143 rotates. Furthermore, bellows 50 is arranged so that when it deforms in accordance with the rotation of movable member 40, bellows 50 does not interfere with the imaging field of view of reference camera 110.

[0081] This configuration prevents light from entering the imaging space rs from outside the imaging space rs. Furthermore, even if a motor or the like generates heat around the imaging space rs, the generated heat is prevented from entering the imaging space rs. This prevents fluctuations from occurring in the atmosphere of the imaging space rs. Therefore, since multiple markers ep are captured with high accuracy, the position and orientation of the movable camera 120 relative to the reference camera 110 can be calculated with high accuracy. Furthermore, with the above configuration, the internal space of the bellows 50 is spatially isolated from the external space, thereby stabilizing the atmosphere in the internal space of the bellows 50.

[0082] As shown in FIG. 8 , in the imaging head 100, it is desirable that the center of gravity of the portion (mainly including the movable member 40 and the movable camera 120) provided between the pair of support frames 32, 33 be located on the rotation axis 30c. This stabilizes the rotation of the movable member 40 around the rotation axis 30c. Furthermore, in the imaging head 100, it is desirable that the center of gravity of the portion (mainly including the support member 30, the movable member 40, and the movable camera 120) that rotates relative to the fixed connector 20 be located on the optical axis 110c of the reference camera 110. This stabilizes the rotation of the support member 30 around the optical axis 110c. Furthermore, it is possible to reduce the driving force required to rotate the support member 30 and the movable member 40. This reduces the burden on the driving units, such as the motor. In this example, weights Wa and Wb are attached to the pair of support frames 32, 33 of the support member 30 to adjust the center of gravity of the portion that rotates relative to the fixed connector 20.

[0083] Bird's-eye view camera 180 is provided on fixed connecting part 20 so that its imaging field of view faces forward of imaging head 100. The angle of view of bird's-eye view camera 180 is larger than the angles of view of base camera 110 and movable camera 120. Therefore, the imaging field of view of bird's-eye view camera 180 is larger than the imaging field of view of base camera 110 and movable camera 120.

[0084] In the tracking process described below, the overhead camera 180 is used to capture an image of the probe 200 over a wide range. In this case, even if the probe 200 moves and moves out of the imaging field of the movable camera 120, the probe 200 is imaged by the overhead camera 180, and the rough position of the probe 200 can be identified based on image data obtained by imaging (hereinafter referred to as overhead image data). Based on the identified position, the position and attitude of the movable camera 120 are adjusted so that the probe 200 is positioned within the imaging field of the movable camera 120.

[0085] In this example, the board casing 93 is connected to the lower casing 91 so as to be out of the imaging field of view of the overhead camera 180. This prevents the range that can be imaged by the overhead camera 180 from being limited by the board casing 93.

[0086] Fig. 11 is a bottom view and a side view of the head bottom part 101, and Fig. 12 is a plan view and a side view of the head base 830 of Fig. 1. As shown in Fig. 11, the head bottom part 101 has an annular bottom surface 102 having a circular ring shape and an annular inclined surface 103. The annular inclined surface 103 slopes upward for a certain distance from the inner edge of the annular bottom surface 102 toward its inside. An opening 104 is formed on the inside of the annular inclined surface 103. A vertical hole 105 that opens downward is formed in a predetermined portion of the annular bottom surface 102.

[0087] 12, the head base 830 has an annular support surface 831 and an annular inclined surface 832, each having a circular ring shape. The annular support surface 831 has the same shape as the annular bottom surface 102 of the head bottom portion 101 and is configured to be able to slide relative to the annular bottom surface 102. The annular inclined surface 832 corresponds to the annular inclined surface 103 of the head bottom portion 101 and is inclined upward a certain distance from the inner edge of the annular inclined surface 832 toward the inside thereof. The annular inclined surface 832 is configured to be able to slide relative to the annular inclined surface 103.

[0088] With this configuration, when the head bottom part 101 is attached to the head base 830, the head bottom part 101 is placed on the head base 830. In this state, the annular bottom surface 102 and the annular inclined surface 103 of the head bottom part 101 come into contact with the annular support surface 831 and the annular inclined surface 832 of the head base 830. Next, the user rotates the orientation of the head bottom part 101 by sliding the head bottom part 101 circumferentially on the head base 830.

[0089] Here, a vertical hole 833 opening upward is formed in the annular support surface 831 of the head base 830. The vertical hole 833 corresponds to the vertical hole 105 of the head bottom portion 101 and overlaps when the head bottom portion 101 and the head base 830 are in a predetermined positional relationship. Therefore, for example, an extendable pin member (not shown) is inserted into one of the two vertical holes 105, 833. In this case, by rotating the head bottom portion 101 on the head base 830, the pin member is inserted into both vertical holes 105, 833 when the head bottom portion 101 and the head base 830 are in a predetermined positional relationship. This fixes the head bottom portion 101 and the head base 830 in a predetermined positional relationship. This completes the attachment of the head bottom portion 101 to the head base 830.

[0090] 2 has an annular support surface 831 and an annular inclined surface 832, similar to the head base 830 described above. This allows the head bottom 101 of the imaging head 100 to be attached to the head base 911, similar to the example of the head base 830.

[0091] It is desirable that the center of gravity of the entire imaging head 100 be located within an area inside the outer edge of the head bottom 101 in a plan view. In Fig. 7, the outer edge of the head bottom 101 when the imaging head 100 is viewed in a plan view is indicated by a thick two-dot chain line. If the center of gravity of the entire imaging head 100 is located inside the outer edge of the head bottom 101 in a plan view, the imaging head 100 will be stably supported when it is attached to the head bases 830, 911.

[0092] 3, reference camera 110, movable camera 120, marker drive circuit 130, rotation drive circuit 140, wireless communication circuit 160, and communication circuit 170 are connected to head control circuit 150. Head control circuit 150 includes a CPU (Central Processing Unit) and memory, or a microcomputer, and controls reference camera 110, movable camera 120, marker drive circuit 130, rotation drive circuit 140, and overhead camera 180.

[0093] As described above, each of reference camera 110, movable camera 120, and overhead camera 180 includes a CMOS image sensor capable of detecting infrared rays. Furthermore, each of reference camera 110, movable camera 120, and overhead camera 180 includes multiple lenses (optical systems, not shown). Analog electrical signals (hereinafter referred to as light-receiving signals) corresponding to the amount of detection are output from each pixel of reference camera 110, movable camera 120, and overhead camera 180 to head control circuit 150.

[0094] Head control circuit 150 is equipped with an A / D converter (analog / digital converter) and a FIFO (first in first out) memory (not shown). The light reception signals output from reference camera 110, movable camera 120, and overhead camera 180 are sampled at a fixed sampling period by the A / D converter of head control circuit 150 and converted into digital signals. The digital signals output from the A / D converter are sequentially stored in the FIFO memory. The digital signals stored in the FIFO memory are sequentially transferred to processing device 300 as pixel data.

[0095] The marker driving circuit 130 drives the light emitting substrate 191 shown in Fig. 10(a) under the control of the head control circuit 150. This causes the multiple light emitting elements L on the light emitting substrate 191 to emit light, and light is emitted from the multiple markers e p of the reference member 190. The timing of this light emission and the imaging timing of the base camera 110 are synchronized.

[0096] Rotation drive circuit 140 drives horizontal rotation mechanism 141 of Fig. 8 under the control of head control circuit 150. This causes support member 30 of Fig. 8 to rotate on fixed connecting part 20, and causes movable member 40 and upper casing 92 (Fig. 4) to rotate. At this time, the rotation of support member 30 causes the imaging field of movable camera 120, which is guided from the inside to the outside of upper casing 92 through rectangular opening 92S (Fig. 4), to rotate horizontally on head base 830 of Fig. 1 or head base 911 of Fig. 2.

[0097] Furthermore, rotation drive circuit 140 drives tilt rotation mechanism 143 (Fig. 8) based on the control of head control circuit 150. This causes movable member 40 (Fig. 8) to rotate about rotation axis 30c between pair of support frames 32, 33. At this time, the imaging field of view of movable camera 120 passing through rectangular opening 92S (Fig. 4) rotates vertically along rectangular opening 92S on head base 830 (Fig. 1) or head base 911 (Fig. 2). The rotation of the imaging field of movable camera 120 by rotation drive circuit 140 is performed based on tracking processing in processing device 300, which will be described later.

[0098] The head control circuit 150 performs wireless communication with the probe 200 via a wireless communication circuit 160. The head control circuit 150 also performs wired communication with the processing device 300 via a communication circuit 170 and a cable CA (FIGS. 1 and 2).

[0099] (2) Processing device 300 3, processing device 300 includes a communication circuit 301, a main body control circuit 302, and a main body memory 303. Communication circuit 301 and main body memory 303 are connected to main body control circuit 302. In addition, a main body operation unit 320 and a main body display unit 310 are connected to main body control circuit 302.

[0100] The main memory 303 includes a ROM (read-only memory), a RAM (random access memory), and a hard disk. The main memory 303 stores a measurement processing program and a tracking processing program (described later) along with a system program. The main memory 303 is also used for processing various data and for storing various data such as pixel data provided by the imaging head 100.

[0101] The main body control circuit 302 includes a CPU. In this embodiment, the main body control circuit 302 and the main body memory 303 are realized by a personal computer. The main body control circuit 302 generates image data based on pixel data provided from the imaging head 100 via the cable CA (FIGS. 1 and 2) and the communication circuit 301. The image data is a collection of multiple pixel data.

[0102] In this embodiment, reference image data, measurement image data, and overhead image data are generated corresponding to the reference camera 110, movable camera 120, and overhead camera 180, respectively, which are provided in the imaging head 100. In addition, image data is generated corresponding to the probe camera 208, which will be described later, which is provided in the probe 200. The main body control circuit 302 calculates the position of the contact portion 211a (FIGS. 1 and 2) of the probe 200 based on the reference image data and measurement image data.

[0103] The main body display unit 310 is configured with, for example, a liquid crystal display panel or an organic EL (electroluminescence) panel. The main body display unit 310 displays the coordinates of measurement points on the measurement target S and the measurement results of each part of the measurement target S under the control of the main body control circuit 302. The main body display unit 310 also displays a screen for making various settings related to the measurement (see measurement screen ms in FIG. 26 described later).

[0104] The main body operation unit 320 includes a keyboard and a pointing device. The pointing device includes a mouse, a joystick, etc. The main body operation unit 320 is operated by the user U.

[0105] [3] Probe 200 configuration (1) Basic configuration of Probe 200 Fig. 13 is a block diagram showing the basic configuration of the probe 200. As shown in Fig. 13, the probe 200 includes, as electrical and magnetic components, a probe control unit 201, an indicator light 202, a battery 203, a marker driving circuit 204, a probe memory 205, a wireless communication circuit 206, a motion sensor 207, a probe camera 208, a probe operation unit 221, a magnet 260, a magnetic sensor 270, and a plurality of (three in this example) target members 290.

[0106] As indicated by the thick two-dot chain line in FIG. 13 , the probe 200 includes a probe holding section 210, a probe casing 220, and a gripping section 230 as components for housing, supporting, or holding the above-mentioned components. The probe holding section 210 holds a plurality of target members 290. A stylus 211 and a magnetic sensor 270 are attached to the probe holding section 210 as a pointer. The stylus 211 is attached to the probe holding section 210 in a predetermined positional relationship with the plurality of target members 290. The stylus 211 is a rod-shaped member having the contact section 211a at its tip. The probe casing 220 houses most of the probe holding section 210 and also houses the probe control section 201, the indicator light 202, the marker driving circuit 204, the probe memory 205, the wireless communication circuit 206, and the motion sensor 207. Furthermore, inside the probe casing 220, a magnet 260 is fixed to a predetermined portion of the probe casing 220.

[0107] The gripping unit 230 has a built-in battery 203. The gripping unit 230 is further provided with a probe operation unit 221. The probe operation unit 221 accepts operation inputs related to measurement from the user U. The probe operation unit 221 includes a trigger switch and a plurality of push buttons. The details of the probe operation unit 221 will be described later.

[0108] The battery 203 is a rechargeable storage battery, and supplies power to other components provided in the probe 200. More specifically, the battery 203 supplies power to at least the target member 290. The probe control unit 201 includes a CPU and memory or a microcomputer, and controls the indicator light 202, the marker drive circuit 204, and the probe camera 208. The probe control unit 201 also performs various processes in response to the operation of the probe operation unit 221 by the user U.

[0109] The indicator light 202 includes, for example, one or more LEDs, and is provided so that its light-emitting portion is exposed to the outside of the probe casing 220. The indicator light 202 performs a light-emitting operation according to the state of the probe 200 under the control of the probe control unit 201.

[0110] Each of the three target members 290 basically has the same configuration as the reference member 190 in Figures 10(a) and (b). The marker driving circuit 204 is connected to the multiple target members 290 and drives the multiple light-emitting elements included in each target member 290 under the control of the probe control unit 201.

[0111] The probe memory 205 includes a recording medium such as a nonvolatile memory or a hard disk. The probe memory 205 stores a system program and a contact trigger output program (described later). The probe memory 205 is also used to process or store various types of data.

[0112] The motion sensor 207 includes a three-axis acceleration sensor and a three-axis gyro sensor, and detects the movement and posture of the probe 200, for example, when a user U moves while carrying the probe 200. Specifically, the motion sensor 207 detects the movement (movement direction and acceleration) and posture of the probe 200 when the probe 200 moves.

[0113] Inside the probe casing 220, the magnet 260 and the magnetic sensor 270 are arranged close to and facing each other. When the positional relationship between the magnet 260 and the magnetic sensor 270 changes with respect to a reference positional relationship, the magnetic sensor 270 detects the amount of change with respect to the reference positional relationship. In other words, when the positional relationship between the magnet 260 and the magnetic sensor 270 changes, the magnetic sensor 270 detects the amount of change in the positional relationship between the magnet 260 and the magnetic sensor 270 with respect to the reference positional relationship as the amount of displacement of the probe holding unit 210 with respect to the probe casing 220. In addition, the magnetic sensor 270 outputs a signal indicating the amount of displacement of the probe holding unit 210 with respect to the probe casing 220 to the probe control unit 201. The probe camera 208 is, for example, a CCD (charge-coupled device) camera.

[0114] In addition to the CPU and memory or microcomputer, the probe control unit 201 is also equipped with an A / D converter and FIFO memory (not shown). As a result, in the probe control unit 201, a signal indicating the movement of the probe 200 detected by the motion sensor 207 is converted into digital signal format data (hereinafter referred to as movement data). Also, in the probe control unit 201, a signal indicating the attitude of the probe 200 detected by the motion sensor 207 is converted into digital signal format data (hereinafter referred to as attitude data). The probe control unit 201 performs a contact trigger output process (described later) using the digital format movement data and attitude data.

[0115] Furthermore, in the probe control unit 201, a signal indicating the displacement amount of the probe holding unit 210 detected by the magnetic sensor 270 is converted into digital signal format data (hereinafter referred to as displacement amount data). The probe control unit 201 performs a contact trigger output process, which will be described later, using the digital displacement amount data. Furthermore, in the probe control unit 201, a light reception signal output from each pixel of the probe camera 208 is converted into a plurality of digital signal format pixel data. The probe control unit 201 transmits the digital format movement data and the plurality of pixel data to the imaging head 100 of FIG. 3 via the wireless communication circuit 206 by wireless communication. In this case, the pixel data is further transferred from the imaging head 100 to the processing device 300.

[0116] (2) External structure of the probe 200 Fig. 14 is an external perspective view of probe 200 seen in one direction, and Fig. 15 is an external perspective view of probe 200 seen in another direction. In the following description, a structure consisting of multiple components housed in probe casing 220 in Fig. 13 and probe holding section 210 will be referred to as main body section 250 of probe 200. As shown in Figs. 14 and 15, main body section 250 is formed to extend in one direction and has a front end section 251, a rear end section 252, a top surface section 253, a bottom surface section 254, one side surface section 255, and the other side surface section 256. In the following description, a direction parallel to the direction in which front end section 251 and rear end section 252 of main body section 250 are aligned in probe 200 will be referred to as a first direction dr1.

[0117] The front end 251 is provided with a plurality of attachment portions to which the stylus 211 can be attached. The attachment portions are configured to face in different directions from one another. The user U can attach the stylus 211 to a desired one of the attachment portions. As a result, the stylus 211 is attached to the front end 251 in one of a plurality of orientations corresponding to the attachment portions. In the examples of FIGS. 14 and 15 , the stylus 211 is attached to the front end 251 so as to extend in a first direction dr1. The front end 251 is further provided with a probe camera 208.

[0118] As shown in FIG. 14 , three target members 290 and a wireless communication circuit 206 are provided in this order on the top surface 253 of the main body 250, aligned from the front end 251 to the rear end 252. Of the three target members 290 in this example, the target member 290 closest to the front end 251 has three markers eq. Each of the remaining two target members 290 has two markers eq. All of the marker surfaces of the target members 290 on which the markers eq are provided are provided on the top surface 253 of the main body 250 and face the same direction. Each marker eq is a self-luminous marker that emits infrared light. The light emission timing of these multiple markers eq is synchronized with the imaging timing of the movable camera 120 of the imaging head 100.

[0119] As shown in FIG. 15 , a connection portion 254j for connecting the grip portion 230 is formed on the bottom surface 254 of the main body 250, slightly closer to the front end 251 than the rear end 252. In the main body 250, the top surface 253 on which the marker eq is provided and the bottom surface 254 on which the connection portion 254j is provided are located on opposite sides. Therefore, the connection portion 254j is provided on the opposite side of the marker surface on which the marker eq is provided. The grip portion 230 has a rod shape that can be held by a user U with one hand. When carrying the probe 200, the user U holds the grip portion 230. The gripping posture of the grip portion 230 is specified, for example, in a user's manual, based on the ease of handling when the user U carries the probe 200. As shown in FIG. 14 , the grip portion 230 of this embodiment has a recessed shape on the stylus 211 side, and it is expected that the user U will hold the probe 200 by placing their fingers in the recess. Therefore, it can be said that the gripping posture when the user U grips the grip portion 230 is also determined by the shape of the grip portion 230. One end of the grip portion 230 is connected to the connection portion 254j via a hinge 254h (FIG. 20), which will be described later. In this state, the grip portion 230 is rotatable around a rotation axis RA that passes through the connection portion 254j and is parallel to the first direction dr1. Since the rotation axis RA is along the marker surface on which the marker eq is provided, the rotation of the grip portion 230 around the rotation axis RA changes the position of the user U, who grips the grip portion 230 in accordance with the gripping posture, relative to the marker surface. Since the rotation axis RA of the grip portion 230 relative to the main body 250 is determined by being connected to the connection portion 254j, the grip portion 230 is rotatable around the rotation axis RA as a predetermined rotation axis.

[0120] 14 and 15, the grip portion 230 extends from the connection portion 254j in a second direction dr2 intersecting with the first direction dr1. An operation surface 221a is provided at a portion of one end of the grip portion 230 facing the rear end portion 252 as part of the probe operation portion 221 of FIG. 13. The operation surface 221a includes a plurality of push buttons 221b (four in this example), and is configured so that a user holding the grip portion 230 can operate the plurality of push buttons 221b with, for example, their thumbs. Furthermore, a trigger switch 221c is provided at a portion of one end of the grip portion 230 facing the front end portion 251 as part of the probe operation portion 221 of FIG. 13. The user holding the grip portion 230 can operate the trigger switch 221c with, for example, their index finger. In this way, the gripping unit 230 is provided with the push button 221b on the operation surface 221a and the trigger switch 221c based on the expected gripping posture of the user U. In other words, the gripping posture when the user U grips the gripping unit 230 is also determined by the arrangement of the probe operation unit 221.

[0121] A connector for charging the battery 203 is provided at the other end of the gripping portion 230. When charging the battery 203, a power cable EC is connected from outside the probe 200 to the connector of the gripping portion 230. When charging of the battery 203 is completed, the power cable EC is pulled out from the connector of the gripping portion 230. The power cable EC may be a cable that enables communication between the probe 200 and the processing device 300. Alternatively, a connector separate from the connector to which the power cable EC is connected may be provided, and a cable that enables communication between the probe 200 and the processing device 300 may be connected to the connector. For example, a USB connector may be provided separate from the connector to which the power cable EC is connected. In this way, even when a connector separate from the connector to which the power cable EC is connected is provided, it is preferable that the connector be provided on the gripping portion 230. When the user U carries the probe 200, the cable is located at the user U's hand, so that the cable is less likely to interfere with imaging of the marker eq.

[0122] Here, hinge 254h ( FIG. 20 ) used to connect connecting portion 254j and grip portion 230 has a so-called click mechanism. As a result, when the rotation angle of grip portion 230 around rotation axis RA is at one of a plurality of predetermined rotation angles, hinge 254h generates a holding force for holding grip portion 230 at that rotation angle. Therefore, when the rotation angle of grip portion 230 around rotation axis RA is at one of a plurality of predetermined rotation angles, user U can stably measure measurement target S while holding grip portion 230. In this embodiment, hinge 254h has a click mechanism, but this does not prevent grip portion 230 from being held at a rotation angle other than the plurality of predetermined rotation angles. As a result, user U can carry probe 200 with grip portion 230 rotated so that grip portion 230 is held at a suitable position within the rotation angle range of grip portion 230.

[0123] In this embodiment, a first rotation angle and a second rotation angle are set as part of a plurality of predetermined rotation angles. In this case, the gripper 230 can transition between a first state in which the rotation angle of the gripper 230 is at the first rotation angle and a second state in which the rotation angle of the gripper 230 is at the second rotation angle. The state of the gripper 230 shown in FIGS. 14 and 15 is referred to as the first state. Note that in this embodiment, the rotation angle indicates the rotation position of the gripper 230 relative to an arbitrary reference rotation position around the rotation axis RA. In other words, a state in which the rotation angle of the gripper 230 is at the first rotation angle indicates a state in which the gripper 230 has rotated by the first angle relative to an arbitrary reference rotation position.

[0124] Fig. 16 is an external perspective view of probe 200 when gripping portion 230 is in the second state, as viewed in one direction, and Fig. 17 is an external perspective view of probe 200 when gripping portion 230 is in the second state, as viewed in another direction. The rotation angle (second rotation angle) of gripping portion 230 shown in Figs. 16 and 17 is different by approximately 90° from the rotation angle (first rotation angle) of gripping portion 230 shown in Figs. 14 and 15. As shown in Figs. 16 and 17, gripping portion 230 in the second state extends from connecting portion 254j (Figs. 14 and 15) in a third direction dr3 that is different from second direction dr2.

[0125] In this embodiment, in addition to the first and second rotation angles, a third rotation angle that is approximately −90° different from the first rotation angle is also set as part of the plurality of predetermined rotation angles. In this case, by setting the rotation angle of gripper 230 to the third rotation angle, gripper 230 can be set to a third state that is different from the first and second states.

[0126] 15, the multiple push buttons 221b are arranged such that the substantially rectangular push buttons 221b are located closer to the main body 250 in the second direction dr2, and the substantially triangular push buttons 221b having sides substantially parallel to the long sides of the substantially rectangular push buttons 221b are located farther from the main body 250 in the second direction dr2. In contrast, in the state shown in FIG. 17, the multiple push buttons 221b are arranged such that the substantially rectangular push buttons 221b are located closer to the main body 250 in the second direction dr2, and the substantially triangular push buttons 221b having sides substantially parallel to the short sides of the substantially rectangular push buttons 221b are located. Therefore, the arrangement of the multiple push buttons 221b with respect to the main body 250 changes before and after the grip 230 is rotated from the first rotation angle shown in FIG. 15 to the second rotation angle shown in FIG. 17.

[0127] Although the above embodiment is configured such that the operation surface 221a of the probe operation unit 221 is provided with multiple push buttons 221b, the present invention is not limited to this. The operation surface 221a may be configured to have a display screen capable of displaying multiple graphical interfaces and receiving user operations on the graphical user interfaces. In this case, the multiple graphical user interfaces displayed on the display screen correspond to the multiple push buttons. Even in this configuration, if the arrangement of the multiple graphical user interfaces with respect to the operation surface 221a remains the same before and after the rotation of the grip unit 230, the arrangement of the multiple graphical user interfaces with respect to the main body unit 250 changes before and after the rotation of the grip unit 230.

[0128] The user U holds the grip portion 230 so that the top surface 253 of the main body 250 faces the imaging head 100. Then, the user U operates the probe operation portion 221 while bringing the contact portion 211a into contact with a desired portion of the measurement target S.

[0129] Figure 18 is a schematic diagram showing a state in which a user U measures a measurement object S using a probe 200 whose gripping portion 230 is in a first state, and Figure 19 is a schematic diagram showing a state in which a user U measures a measurement object S using a probe 200 whose gripping portion 230 is in a second state.

[0130] 14 and 15, the second direction dr2 along which grip unit 230 is aligned in the first state is a direction intersecting with top surface 253 of main body 250 on which the marker surfaces are provided. Therefore, as shown in Fig. 18, when user U grips grip unit 230 at the first rotation angle in a specified gripping posture, user U can point the multiple marker surfaces toward movable camera 120 located directly opposite user U.

[0131] 16 and 17, the third direction dr3 along which grip unit 230 is oriented at a second rotation angle different from the first rotation angle is a direction along top surface 253 of main body 250 on which the marker surfaces are provided, and is a direction intersecting with first direction dr1. Therefore, as shown in Fig. 19, when user U grips grip unit 230 at the second rotation angle in a specified gripping posture, user U can point multiple marker surfaces toward movable camera 120 located to the side of user U.

[0132] Therefore, when the user U holds the grip unit 230 according to the specified gripping posture, the direction in which the marker surface faces in the first state is different from the direction in which the marker surface faces in the second state, as viewed from the user U. As described above, even when the user U holds the grip unit 230 according to the specified gripping posture, the multiple markers eq are arranged in different directions when the grip unit 230 is in the first state and when the grip unit 230 is in the second state. Therefore, by switching the grip unit 230 between the first state and the second state, the user U can change the relative position and posture of the measurement object S and the imaging head 100 having the movable camera 120 with the upper surface 253 of the main body 250 facing the imaging head 100 having the movable camera 120.

[0133] 14 to 17, a first display unit 202a constituting the indicator light 202 of Fig. 13 is provided on one side surface 255 of the main body 250 between the front end 251 in the first direction dr1 and the connecting portion 254j. Also, a second display unit 202b constituting the indicator light 202 of Fig. 13 is provided on the other side surface 256 of the main body 250 between the front end 251 in the first direction dr1 and the connecting portion 254j.

[0134] Each of the first display unit 202a and the second display unit 202b includes a plurality of green LEDs and a plurality of red LEDs. When the plurality of markers eq provided on the upper surface 253 of the probe 200 are present within the imaging field of the movable camera 120 (FIG. 3), the first display unit 202a and the second display unit 202b emit green light. On the other hand, when the plurality of markers eq are not present within the imaging field of the movable camera 120, the first display unit 202a and the second display unit 202b emit red light.

[0135] In the main body 250, the first display unit 202a and the second display unit 202b are located between the grip unit 230 and the stylus 211. This allows the user U to indicate a measurement point by contacting the contact unit 211a with a desired portion of the measurement target S while viewing the first display unit 202a and the second display unit 202b.

[0136] Furthermore, one side surface 255 on which the first display unit 202a is provided and the other side surface 256 on which the second display unit 202b is provided are surfaces of the main body 250 facing in opposite directions. Because the direction in which the first display unit 202a faces is different from the direction in which the second display unit 202b faces, the angle range at which the user U can view these displays is different. Therefore, even if the user U has difficulty viewing the first display unit 202a while operating the probe 200, the user U can easily determine whether multiple markers eq are present within the imaging field of the movable camera 120 as long as he or she can view the second display unit 202b. Furthermore, even if the user U has difficulty viewing the second display unit 202b while operating the probe 200, the user U can easily determine whether multiple markers eq are present within the imaging field of the probe holder 210 as long as he or she can view the first display unit 202a. This improves the operability of the probe 200 when specifying measurement points.

[0137] (3) Internal structure of the main body 250 of the probe 200 20 is a partially cutaway cross-sectional view of the probe 200 showing the internal structure of the main body 250. FIG. 21 is an exploded perspective view of the probe 200 for explaining the outline of the internal structure of the main body 250.

[0138] As shown in Figure 20, the probe holder 210 is mainly composed of a stylus mounting portion 210a and a target member holder 210b. The stylus mounting portion 210a and the target member holder 210b are made of a material with low moisture absorption and a small linear expansion coefficient. In this embodiment, the stylus mounting portion 210a is made mainly of Invar (an alloy consisting of 64% iron and 36% nickel). The target member holder 210b is made mainly of quartz glass.

[0139] The stylus mounting portion 210a is provided with a plurality of mounting portions to which the stylus 211 can be attached. The target member holding portion 210b is formed to extend in one direction and holds a plurality of target members 290. The stylus mounting portion 210a is attached to one end of the target member holding portion 210b. The stylus mounting portion 210a and the target member holding portion 210b are connected so that their relative positions do not change. As a result, when the stylus 211 is attached to the stylus mounting portion 210a, the positional relationship between the contact portion 211a of the stylus 211 and the plurality of target members 290 is fixed to a predetermined positional relationship. Note that the probe holding portion 210 is not limited to the examples shown in FIGS. 20 and 21 , and may be formed of a single member.

[0140] On the other hand, the probe casing 220 is mainly composed of an upper casing 220a and a lower casing 220b. As shown in Fig. 21, when assembling the probe 200, the upper casing 220a and the lower casing 220b are arranged to sandwich the probe holding part 210 and the multiple rubber bushings rb therebetween.

[0141] Here, as shown in FIG. 20 , upper casing 220a has opening 299 formed at a position corresponding to target member 290. A light-transmitting member that does not interfere with movable camera 120 capturing an image of target member 290 may be disposed in opening 299. With this configuration, target member 290 is not exposed to the outside of upper casing 220a, thereby reducing the possibility of target member 290 becoming contaminated. Furthermore, although this embodiment is configured such that opening 299 is formed at a position corresponding to target member 290, upper casing 220a itself may be made of a light-transmitting member that does not interfere with movable camera 120 capturing an image of target member 290. Note that opening 299 is not shown in FIG. 21 .

[0142] Here, the upper casing 220a is formed with three through holes h1 into which the shanks of the three screws sc can be inserted. Furthermore, the target member holding portion 210b of the probe holding portion 210 is formed with three through holes h2 corresponding to the three through holes h1 of the upper casing 220a. Furthermore, the lower casing 220b has a support portion that supports the target member holding portion 210b. The support portion is formed with three through holes h3 (FIG. 20) corresponding to the three through holes h1 of the upper casing 220a and the three through holes h2 of the target member holding portion 210b.

[0143] The upper casing 220a and the lower casing 220b are connected together using three screws sc. The state of one of the three connected parts connected together using the three screws sc is shown in a balloon in FIG.

[0144] As shown in more detail in the speech bubble in Figure 20, in each connection, a metal collar ca is inserted into the through-hole h2 of the target member holder 210b. A screw sc is inserted through the through-hole h1 of the upper casing 220a, the collar ca, and the through-hole h3 of the lower casing 220b, and a nut nt is attached to the tip of the screw sc. A washer wa is placed between the top surface of the upper casing 220a and the head of the screw sc, and another washer wa is placed between the support of the lower casing 220b and the nut nt.

[0145] Furthermore, a flexible rubber bushing rb is arranged between the upper casing 220a and the target member holding portion 210b. Furthermore, a flexible rubber bushing rb is arranged between the target member holding portion 210b and the lower casing 220b. The stylus attachment portion 210a and the target member holding portion 210b have high rigidity, and are firmly fixed to each other. Therefore, when the stylus 211 comes into contact with the measurement object S, the displacement of the probe holding portion 210 relative to the probe casing 220 is dominant over the deformation between the stylus attachment portion 210a and the target member holding portion 210b. In other words, the selection and arrangement of the rubber bushing rb as an elastic body relative to the rigidity that fixes the stylus mounting portion 210a and the target member holding portion 210b are determined so that the displacement between the probe casing 220 and the probe holding portion 210 becomes dominant over the displacement between the stylus 211 and the target member 290 when the user U brings the stylus 211 into contact with the measurement object S.

[0146] With this configuration, the probe holding part 210 is held by the multiple rubber bushings rb so that it can move within the probe casing 220. That is, the probe holding part 210 is held in a loose state inside the probe casing 220. The rubber bushings rb are provided at positions corresponding to the screws sc, so two are lined up on the stylus 211 side and one is located on the magnetic sensor side.

[0147] Specifically, the probe-holding portion 210 is held so as to be movable by about 2 mm, for example, in the up-down direction of the main body portion 250 (the direction in which the top surface portion 253 and the bottom surface portion 254 are aligned), when a load of about 1 N is applied to the probe casing 220. The probe-holding portion 210 is held so as to be movable by about 2 mm, for example, in the left-right direction of the main body portion 250 (the direction in which the one side surface portion 255 and the other side surface portion 256 are aligned), when a load of about 2 N is applied to the probe-holding portion 210 or the probe casing 220. The probe-holding portion 210 is held so as to be movable by about 0.3 mm, for example, in the front-rear direction of the main body portion 250 (the direction in which the front end portion 251 and the rear end portion 252 are aligned).

[0148] As described above, the rubber bushes rb are provided at positions corresponding to the screws sc, so two are positioned side by side on the stylus 211 side, and one is positioned on the magnetic sensor side. Therefore, when a load is applied to the probe holding part 210 or the probe casing 220 in the up-down direction of the main body 250 with the stylus 211 in contact with the measurement target S, the load is applied in a direction away from the plane including the three rubber bushes rb. At this time, the two rubber bushes rb on the stylus 211 side serve as fulcrums, and only the rubber bush rb on the magnetic sensor 270 side repels the load. Therefore, even if the applied load is relatively small, the probe holding part 210 moves relative to the probe casing 220. Furthermore, when a load is applied to the probe holding part 210 or the probe casing 220 in the front-rear direction of the main body 250 with the stylus 211 in contact with the measurement target S, the three rubber bushes rb repel the load, so the amount of movement of the probe holding part 210 relative to the probe casing 220 is small, even if a relatively large load is applied.

[0149] In this case, for example, when the contact portion 211a of the stylus 211 is in contact with the measurement object S, even if a load directed toward the measurement object S is applied to the gripping portion 230, the multiple rubber bushings rb function as buffer members. This suppresses deformation of the probe holding portion 210 and suppresses a decrease in measurement accuracy caused by a misalignment of the positional relationship between the stylus 211 and the multiple target members 290.

[0150] Furthermore, according to the above configuration, even if the probe casing 220 is subjected to an impact due to a drop or collision of the probe 200, the impact transmitted from the probe casing 220 to the probe holding part 210 is absorbed by the multiple rubber bushings rb, thereby preventing damage to the probe holding part 210.

[0151] 20 and 21 , the magnetic sensor 270 is fixed to the lower end of the other end of the target member-holding part 210b. Meanwhile, the magnet 260 is fixed to the bottom of the lower casing 220b so as to be spaced apart from and face the magnetic sensor 270 when the probe-holding part 210 is housed in the probe casing 220. With this arrangement, when the probe-holding part 210 moves relative to the probe casing 220, the amount of change in the magnetic force applied to the magnetic sensor 270 by the magnet 260 is detected as the amount of displacement of the probe-holding part 210 relative to the probe casing 220.

[0152] In this embodiment, the first direction dr1 in the probe 200 is defined as a direction parallel to the direction in which the front end 251 and the rear end 252 of the main body 250 are aligned. Meanwhile, as described above, the probe holding part 210 is held within the probe casing 220 via a plurality of rubber bushings rb. Therefore, when a relative load is applied between the probe holding part 210 and the probe casing 220, such as when the stylus 211 is brought into contact with the measurement target S, the positional relationship between the front end 251 and the rear end 252 of the main body 250 changes. Therefore, in this embodiment, the first direction dr1 is defined in a state in which no relative load is applied between the probe holding part 210 and the probe casing 220 and the probe 200 is in a predetermined posture.

[0153] 20 shows a cross section of the connection portion between main body portion 250 and grip portion 230, in addition to a cross section of main body portion 250. As shown in Fig. 20, main body portion 250 and connection portion 254j are rotatably connected by hinge 254h. Hinge 254h in this example includes a hollow member hi1 that guides cables or the like between the internal space of grip portion 230 and the internal space of main body portion 250, and an axis member hi2 that supports grip portion 230 with respect to connection portion 254j.

[0154] [4] How to calculate the coordinates of the measurement points In the three-dimensional coordinate measuring device 1 according to this embodiment, a three-dimensional coordinate system (hereinafter referred to as the device coordinate system) having a predetermined relationship with the reference camera 110 is defined in advance. In addition, the main memory 303 of the processing device 300 stores in advance the relative positional relationships of the multiple markers ep on the reference member 190.

[0155] As described above, the reference camera 110 captures images of the multiple markers ep on the reference member 190. In this case, the main body control circuit 302 in Fig. 3 calculates the coordinates of each marker ep in the device coordinate system based on the reference image data obtained by capturing the image and the positional relationship of the multiple markers ep stored in the main body memory 303. At this time, each of the multiple markers ep on the reference member 190 is identified based on the first and second markers ep1 and ep2.

[0156] Then, based on the calculated coordinates of the multiple markers ep, the main body control circuit 302 generates information indicating the position and orientation of the movable camera 120 fixed on the reference member 190 in the device coordinate system as first position and orientation information.

[0157] In the three-dimensional coordinate measuring device 1 according to this embodiment, in addition to the device coordinate system described above, a three-dimensional coordinate system (hereinafter referred to as a movable coordinate system) having a predetermined relationship with the movable camera 120 is defined in advance. Furthermore, the main memory 303 of the processing device 300 stores in advance the relative positional relationships of the plurality of markers eq on the probe 200.

[0158] As described above, the movable camera 120 captures images of the multiple markers eq of the probe 200. In this case, the main body control circuit 302 in Fig. 3 calculates the coordinates of each marker eq in the movable coordinate system based on the measurement image data obtained by capturing the images and the positional relationship of the multiple markers eq stored in the main body memory 303.

[0159] Thereafter, the main body control circuit 302 generates, as second position and orientation information, information indicating the position and orientation of the probe 200 in the movable coordinate system based on the calculated coordinates of the plurality of markers eq.

[0160] The reference camera 110 is fixed on the head bottom 101. Therefore, the device coordinate system does not change when measuring the measurement target S. On the other hand, the movable camera 120 is rotatably provided so that the imaging field of view follows the movement of the probe 200. Therefore, the relationship between the device coordinate system and the movable coordinate system changes as the movable camera 120 rotates.

[0161] Therefore, in this embodiment, the main body control circuit 302 generates third position and orientation information that expresses the position and orientation of the probe 200 in the device coordinate system based on the first and second position and orientation information. That is, the main body control circuit 302 calculates the relative relationship of the movable coordinate system with respect to the device coordinate system based on the first position and orientation information, and converts the second position and orientation information into information that conforms to the device coordinate system based on the calculated relationship. In this way, the third position and orientation information is generated.

[0162] Thereafter, the main body control circuit 302 calculates the coordinates of the measurement point indicated by the probe 200 based on the generated third position and orientation information and the positional relationship between the plurality of markers eq on the probe 200 and the contact portion 211a.

[0163] [5] Measurement example The probe operation unit 221 in Fig. 13 is pressed by the user U to specify a measurement point, i.e., to calculate the coordinates of the measurement point. For example, the user U operates one of the multiple push buttons 221b and the trigger switch 221c of the probe operation unit 221 with the contact unit 211a in contact with a desired portion of the measurement target S. This causes the probe 200 to output a signal indicating the measurement point (hereinafter referred to as a measurement point specification signal). In this case, the processing device 300 calculates the coordinates of the portion of the measurement target S that is in contact with the contact unit 211a as the coordinates of the measurement point. The calculated coordinates of the measurement point are stored in the main body memory 303 as the measurement result and are also displayed on the main body display unit 310.

[0164] In the three-dimensional coordinate measuring device 1, the user U can set the desired measurement conditions for the measurement object S by operating the main body operation unit 320 in FIG. 3 or the probe operation unit 221 in FIG. 13.

[0165] Specifically, the user U selects geometric elements and measurement items for the measurement object S. The geometric elements are types of geometric shapes that indicate the shape of the part to be measured on the measurement object S. Types of geometric shapes include points, lines, planes, circles, cylinders, and spheres. Furthermore, the measurement items indicate what should be measured on the measurement object S, and include various physical quantities such as distance, angle, and flatness.

[0166] For example, a geometric element is selected. After selecting the geometric element, the user U specifies one or more measurement points for the selected geometric element using the probe 200. This generates information (hereinafter referred to as element-specific information) that indicates the selected geometric element, which is identified by one or more measurement points on the measurement target S, in the device coordinate system. Then, a measurement item is selected. After selecting the measurement item, the value of the selected measurement item is calculated with respect to the generated element-specific information.

[0167] For example, if a user U wants to measure the distance between the first and second surfaces of a measurement object S having parallel and opposite first and second surfaces, the user selects the geometric elements "Plane 1" and "Plane 2."

[0168] In this case, in order to identify a plane (first surface) on the measurement object S that corresponds to the geometric element "plane 1," the user U uses the probe 200 to specify multiple (three or more points in this example) portions of the first surface of the measurement object S as measurement points. As a result, element identification information corresponding to the geometric element "plane 1" is generated.

[0169] Furthermore, in order to identify a plane (second surface) on the measurement object S that corresponds to the geometric element "plane 2," the user U uses the probe 200 to designate multiple (three or more points in this example) portions of the second surface of the measurement object S as measurement points. As a result, element identification information that corresponds to the geometric element "plane 2" is generated.

[0170] Then, the measurement item "distance" is selected. At this time, user U specifies that "distance" is the distance between "Plane 1" and "Plane 2" for which element identification information has been generated. As a result, the distance between the first and second surfaces of measurement object S corresponding to the measurement item "distance" is calculated based on the two pieces of element identification information corresponding to the geometric elements "Plane 1" and "Plane 2," respectively. The calculated measurement result is stored in main unit memory 303 and displayed on main unit display unit 310.

[0171] [6] Measurement processing Figure 22 is a flowchart showing the flow of measurement processing by main body control circuit 302 of Figure 3. The measurement processing of Figure 22 is performed repeatedly at a predetermined interval by the CPU of main body control circuit 302 of Figure 3 executing a measurement processing program stored in main body memory 303. Furthermore, at the start of measurement processing, a timer built into main body control circuit 302 is reset and started.

[0172] First, the main body control circuit 302 determines whether or not a geometric element and a measurement item have been selected based on whether or not the user U has operated the main body operation unit 320 in Fig. 3 (step S11). The selection of the geometric element and the measurement item may also be performed based on the operation of the probe operation unit 221 in Fig. 13 as described above. In this case, the main body control circuit 302 determines whether or not a geometric element and a measurement item have been selected based on whether or not a signal regarding the selection of the geometric element and the measurement item has been received from the probe 200.

[0173] When the geometric elements and measurement items have been selected, the main body control circuit 302 sets the geometric elements and measurement items as measurement conditions by storing the selected geometric elements and measurement items in the main body memory 303 of Fig. 3 (step S12). After that, the main body control circuit 302 returns to the processing of step S11.

[0174] If no selection of a geometric element and measurement item is performed in step S11, the main body control circuit 302 determines whether or not a geometric element and measurement item have been set (step S13). If the geometric element and measurement item have been set, the main body control circuit 302 determines whether or not a command to start measurement of the measurement target S has been received (step S14). This determination is made based on, for example, whether or not the user U has operated the main body operation unit 320.

[0175] When a command to start measuring the measurement target S is received, the main body control circuit 302 performs a measurement point coordinate calculation process (step S15). The measurement point coordinate calculation process will be described in detail later. Through this process, the main body control circuit 302 calculates the coordinates of the measurement point for identifying the selected geometric element based on the operation of the probe 200 by the user.

[0176] Furthermore, the main body control circuit 302 stores the coordinates of one or more measurement points calculated by the measurement point coordinate calculation process in step S15 in the main body memory 303 (step S16).

[0177] Next, the main body control circuit 302 determines whether or not a command to end the measurement of the measurement object S has been received (step S17). This determination is made based on whether or not the user U has operated the main body operation unit 320, for example.

[0178] If the command to end measurement is not received, the main body control circuit 302 returns to the processing of step S15. On the other hand, if the command to end measurement is received, the main body control circuit 302 generates element identification information for the geometric element set from the coordinates of one or more measurement points stored in the main body memory 303 in the processing of the immediately preceding step S16 (step S18).

[0179] Thereafter, the main body control circuit 302 calculates the values ​​of the measurement items set based on the element identification information generated in the process of step S18 (step S19), and ends the measurement process. Note that if multiple geometric elements (for example, two planes) have been set at the time of determination in step S13, the processes of steps S14 to S18 are performed for each of the set geometric elements.

[0180] If no geometric elements and measurement items are set in step S13 and no command to start measuring the object S to be measured is received in step S14, the main control circuit 302 determines whether a predetermined time has elapsed since the measurement process was started, based on the time measured by the built-in timer (step S20).

[0181] If the predetermined time has not elapsed, the main body control circuit 302 returns to the processing of step S11. On the other hand, if the predetermined time has elapsed, the main body control circuit 302 performs a measurement point coordinate calculation process (step S21), which will be described later, similar to the processing of step S15. Thereafter, the main body control circuit 302 ends the measurement processing.

[0182] The process of step S21 is performed to determine whether or not the probe 200 is within the imaging field of the movable camera 120 or the overhead camera 180 in the tracking process, which will be described later, for example.

[0183] 23 is a flowchart showing the flow of the measurement point coordinate calculation process. First, the main body control circuit 302 requests the probe control unit 201 of the probe 200 to output a contact trigger (step S101). The contact trigger will be described in detail later. Thereafter, the main body control circuit 302 determines whether or not a contact trigger has been received from the probe 200 (step S102).

[0184] If a contact trigger is not received in step S102, the main body control circuit 302 repeats the process of step S102. On the other hand, if a contact trigger is received, the main body control circuit 302 determines whether or not the user U has operated the probe operation unit 221 to indicate a measurement point. That is, the main body control circuit 302 determines whether or not a measurement point indication signal has been received from the probe 200 based on the operation of the probe operation unit 221 by the user U (step S103).

[0185] If a measurement point indication signal is not received in step S103, the main body control circuit 302 repeats the process of step S103. On the other hand, if a measurement point indication signal is received, the main body control circuit 302 commands the probe control unit 201 of the probe 200 to emit light from multiple markers eq (FIG. 14), and commands the head control circuit 150 of the imaging head 100 to emit light from multiple markers ep of the reference member 190 (FIG. 10(b)) (step S104).

[0186] Next, the main body control circuit 302 generates reference image data by causing the head control circuit 150 to capture images of the multiple markers ep on the reference member 190 using the reference camera 110 (step S105). Furthermore, the main body control circuit 302 generates first position and orientation information that indicates the position and orientation of the movable camera 120 in the device coordinate system based on the generated reference image data (step S106).

[0187] Next, the main body control circuit 302 generates measurement image data by capturing images of the multiple markers eq of the probe 200 using the movable camera 120 (step S107). Furthermore, the main body control circuit 302 generates second position and orientation information indicating the position and orientation of the probe 200 in a movable coordinate system based on the generated measurement image data (step S108).

[0188] Thereafter, the main body control circuit 302 generates third position and orientation information that represents the position and orientation of the probe 200 in the device coordinate system based on the first and second position and orientation information (step S109). Furthermore, the main body control circuit 302 calculates the coordinates of the measurement point indicated by the probe 200 based on the generated third position and orientation information (step S110).

[0189] In the above measurement point coordinate calculation process, the process of step S103 may be omitted. In this case, the main body control circuit 302 performs the process of step S104 in response to a contact trigger output from the probe 200. Note that the processes of steps S105 and S106 and the processes of steps S107 and S108 may be performed in the reverse order.

[0190] Furthermore, with regard to the processing of steps S104 and S107 described above, the main body control circuit 302 may output an image capture command for the movable camera 120 to capture the multiple markers eq before instructing the probe 200 to emit light from the multiple markers eq (FIG. 14). Alternatively, the main body control circuit 302 may output an image capture command and an image capture command so that the image capture timing of the movable camera 120 is synchronized with the light emission timing of the multiple markers eq. In this case, it is desirable to output the image capture command and the image capture command taking into consideration a delay time depending on the type of wireless communication (optical communication or Bluetooth (registered trademark)) between the imaging head 100 and the probe 200. In these cases, the light emission time of the multiple markers eq of the probe 200 can be shortened, thereby reducing the consumption of the battery 203 of the probe 200.

[0191] According to the above measurement process, the user U can easily measure the desired physical quantity in the measurement object S by selecting the desired geometric element and measurement item from a predetermined plurality of geometric elements and a predetermined plurality of measurement items.

[0192] [7] Contact trigger output processing 23, the coordinates of the measurement point are not calculated unless a contact trigger is output from the probe 200 to the processing device 300. In the probe 200, the contact trigger is output by the probe control unit 201 executing the contact trigger output process described below.

[0193] Fig. 24 is a flowchart showing the flow of the contact trigger output process by the probe control unit 201 of Fig. 13. The contact trigger output process of Fig. 24 is repeatedly performed at a predetermined cycle by the CPU of the probe control unit 201 of Fig. 13 executing a contact trigger output program stored in the probe memory 205.

[0194] First, the probe control unit 201 determines whether or not a contact trigger request has been received from the processing device 300 (step S201). If a contact trigger request has not been received, the probe control unit 201 repeats the process of step S201. On the other hand, if a contact trigger has been received, the probe control unit 201 determines whether or not the amount of movement of the probe 200 per unit time is equal to or less than a first threshold value, based on the movement data obtained by the motion sensor 207 (step S202).

[0195] The process of step S202 is a process for determining whether or not the probe 200 is in a state where it has moved significantly relative to the measurement object S (hereinafter referred to as a coarse movement state) at a stage a predetermined time before the measurement point is specified. Therefore, the first threshold value is, for example, a value estimated as the speed of the probe 200 immediately before the measurement point is specified (for example, an acceleration of 1.1 m / sec 2 The value is set to (approximately).

[0196] In the following description, a state in which the probe 200 itself is barely moving and the posture of the probe 200 is changing, and a state in which the probe 200 itself is barely moving and the positional relationship between the probe holding part 210 and the probe casing 220 is changing, are referred to as a precision movement state. The precision movement state of the probe 200 is, for example, the state of the probe 200 immediately before a measurement point is specified.

[0197] In the following description, a state in which the probe 200 itself is barely moving, the attitude of the probe 200 is barely changing, and the positional relationship between the probe holding part 210 and the probe casing 220 is barely changing is referred to as a stationary state. The stationary state of the probe 200 is a state of the probe 200 that is suitable for indicating a measurement point.

[0198] In step S202, if the amount of movement of the probe 200 per unit time is greater than the first threshold, the probe control unit 201 repeats the process of step S202. In this case, it is determined that the probe 200 is moving significantly, i.e., is in a coarse movement state. On the other hand, if the amount of movement of the probe 200 per unit time is equal to or less than the first threshold, the probe control unit 201 determines that the probe 200 itself is barely moving and is at least in a fine movement state. If the amount of movement of the probe 200 per unit time is equal to or less than the first threshold, the probe control unit 201 stores the displacement amount data currently obtained by the magnetic sensor 270 in the probe memory 205 as a magnetic reference value (step S203). The process of step S203 corresponds to setting the reference condition of the present invention.

[0199] Subsequently, in steps S204 to S208 described below, it is determined whether the probe 200 has transitioned from the precision movement state to the stopped state. Specifically, after the process of step S203, the probe control unit 201 resets a timer built in the probe control unit 201 and starts counting (step S204). Thereafter, similar to the process of step S202, the probe control unit 201 determines whether the amount of movement of the probe 200 per unit time is equal to or less than a first threshold value based on the movement data obtained by the motion sensor 207 (step S205). If the amount of movement per unit time is greater than the first threshold value in step S205, the probe control unit 201 returns the process to step S202. On the other hand, if the amount of movement of the probe 200 per unit time is equal to or less than the first threshold value in step S205, the probe control unit 201 determines whether the amount of change in the attitude of the probe 200 per unit time is equal to or less than a second threshold value based on the attitude data obtained by the motion sensor 207 (step S206). That is, the probe control unit 201 determines whether the attitude of the probe 200 is maintained in a substantially stable state.

[0200] If the amount of change in posture is greater than the second threshold, the probe control unit 201 returns the process to step S203. On the other hand, if the amount of change in posture is equal to or less than the second threshold, the probe control unit 201 determines whether a predetermined time limit has elapsed from the start of step S204, based on the count of a built-in timer (step S207).

[0201] In step S207, if a predetermined time limit has elapsed since the start of step S204, the probe control unit 201 returns the process to step S203. As a result, in the process of step S203 after the process of step S207, the magnetic reference value is updated with new displacement amount data every time the time limit has elapsed unless the process of step S209, which will be described later, is performed. This time limit is set to, for example, about 2 to 5 seconds.

[0202] Within the probe casing 220 of the probe 200, the probe holding part 210 is ensured with a relatively high degree of freedom by a plurality of rubber bushings rb. Therefore, when the posture of the probe 200 changes gradually, the probe holding part 210 moves within the probe casing 220 due to its own weight. In contrast, according to the processing of step S206 described above, the magnetic reference value is updated every time the time limit is reached. As a result, even if the magnetic reference value becomes inappropriate due to a gradual change in the posture of the probe 200, an appropriate magnetic reference value is reset using new displacement amount data every time the time limit elapses.

[0203] In step S207, if a predetermined time limit has not elapsed since the start of step S204, the probe control unit 201 determines whether the difference between the displacement amount data currently obtained by the magnetic sensor 270 and the magnetic reference value is equal to or greater than a predetermined third threshold value and equal to or less than a predetermined fourth threshold value (step S208).

[0204] Here, the third threshold value is set to, for example, the displacement amount of the probe holding part 210 that is estimated to change minimally immediately before the measurement point is specified. In other words, the third threshold value is set to the displacement amount of the probe holding part 210 that is estimated when the user U presses the stylus 211 against the measurement object S.

[0205] On the other hand, the fourth threshold value is set to a displacement amount of the probe holding part 210 that is considered inappropriate when indicating a measurement point. Specifically, the fourth threshold value is set to a displacement amount that is lower than the value at which distortion is estimated to occur in the probe holding part 210 due to excessive movement of the probe holding part 210 relative to the probe casing 220. Therefore, it is preferable that the fourth threshold value be updated when the magnetic reference value is updated.

[0206] If the difference between the displacement amount data and the magnetic reference value is not within the range of the third threshold value or more and the fourth threshold value or less in step S208, the probe control unit 201 proceeds to step S205. On the other hand, if the difference between the displacement amount data and the magnetic reference value is within the range of the third threshold value or more and the fourth threshold value or less, the probe control unit 201 outputs a contact trigger as a signal indicating that the current state of the probe 200 allows the measurement point to be appropriately specified (step S209). In other words, the contact trigger is a signal that permits the start of processing for calculating the coordinates of the specified measurement point. The contact trigger is transmitted to the imaging head 100 via the wireless communication circuit 206 and further transmitted from the imaging head 100 to the processing device 300. Therefore, when the difference between the displacement amount data and the magnetic reference value is within a predetermined range, it is determined whether the measurement point specification signal of step S103 has been received. In other words, the probe 200 is often in a state suitable for measurement when the user U operates the probe operation unit 221. This improves the reproducibility of the measurement. It goes without saying that the reproducibility of the measurement is improved even when step S103 is omitted.

[0207] Finally, after outputting the contact trigger, the probe control unit 201 stops processing operations for a certain period of time (step S210). That is, the probe control unit 201 enters a standby state. This processing is performed to prevent a new contact trigger from being output when the contact unit 211a, which has been in contact with the measurement target S, is separated from the measurement target S. The certain period of time in step S210 is, for example, about 0.5 seconds. Thereafter, the contact trigger output processing ends.

[0208] [8] Tracking process Fig. 25 is a flowchart showing the flow of tracking processing by the main body control circuit 302 of Fig. 3. The tracking processing of Fig. 25 is repeatedly performed at a predetermined cycle by the CPU of the main body control circuit 302 of Fig. 3 executing a tracking processing program stored in the main body memory 303.

[0209] First, the main body control circuit 302 determines whether or not the probe 200 is within the imaging field of the movable camera 120 (step S31). This determination is made by determining whether or not the measurement image data generated during the processing of steps S15 and S21 in the measurement process includes image data corresponding to a plurality of markers eq.

[0210] If the probe 200 is within the imaging field of the movable camera 120, the main body control circuit 302 proceeds to the processing of step S36, which will be described later. On the other hand, if the probe 200 is not within the imaging field of the movable camera 120, the main body control circuit 302 determines whether or not the probe 200 is within the imaging field of the overhead camera 180 (step S32). This determination is made by determining whether or not image data corresponding to a plurality of markers eq is included in the overhead image data generated during the processing of steps S15 and S21 in the above measurement processing.

[0211] The motion data generated in the probe 200 is sent from the probe 200 to the processing device 300 via the imaging head 100. If the probe 200 is within the imaging field of the overhead camera 180, the main body control circuit 302 proceeds to the processing of step S35, which will be described later. On the other hand, if the probe 200 is not within the imaging field of the movable camera 120, the main body control circuit 302 determines whether it is possible to estimate the coordinates of the probe 200 based on the motion data transferred from the probe 200 (step S33). This determination is made based on, for example, whether the motion data indicates an abnormal value or whether the value indicated by the motion data is 0. If the motion data indicates an abnormal value or if the motion data is 0, it is impossible to estimate the coordinates of the probe 200.

[0212] If it is not possible to estimate the coordinates of the probe 200, the main body control circuit 302 returns to the processing of step S31. On the other hand, if it is possible to estimate the coordinates of the probe 200, the main body control circuit 302 estimates the position of the probe 200 based on the movement data. The main body control circuit 302 also commands the adjustment of the position and attitude of the movable camera 120 so that the probe 200 is positioned within the imaging field of view of the movable camera 120 (step S34). Thereafter, the main body control circuit 302 returns to the processing of step S31.

[0213] In step S32, if the probe 200 is within the imaging field of the overhead camera 180, the main body control circuit 302 calculates the position of the probe 200 based on the overhead image data. The main body control circuit 302 also instructs the head control circuit 150 to adjust the position and attitude of the movable camera 120 so that the probe 200 is located within the imaging field of the movable camera 120 (step S35).

[0214] Next, when the probe 200 is positioned within the imaging field of view of the movable camera 120, the main body control circuit 302 commands the head control circuit 150 to adjust the position and attitude of the movable camera 120 so that the center of gravity of the multiple markers eq of the probe 200 is positioned at the center of the imaging field of view of the movable camera 120 (step S36). Thereafter, the main body control circuit 302 ends the tracking process.

[0215] According to the above tracking process, even when the probe 200 moves, the imaging field of view of the movable camera 120 tracks the multiple markers eq of the probe 200. This eliminates the need for the user U to manually adjust the imaging field of view of the movable camera 120. Therefore, it becomes possible to measure the coordinates of desired measurement points on the measurement target S over a wide range without requiring any complicated adjustment work.

[0216] [9] Effects (1) In the above-described probe 200, the contact portion 211a of the stylus 211 is brought into contact with the measurement object S to indicate a measurement point. The stylus 211 and the probe holding portion 210 are connected to each other in a predetermined positional relationship. The coordinates of the indicated measurement point are calculated based on image data obtained by capturing images of multiple markers eq held in the probe holding portion 210 and the positional relationship between the stylus 211 and the probe holding portion 210. Therefore, it is desirable that the load applied to the measurement object S from the contact portion 211a of the stylus 211 when indicating a measurement point is of a magnitude that does not change the positional relationship between the stylus 211 and the probe holding portion 210. In other words, it is desirable that the load is of a magnitude that does not cause excessive distortion in the stylus 211 and the probe holding portion 210.

[0217] In the probe 200 described above, the probe holding portion 210 is connected to the probe casing 220 so as to be freely movable. Therefore, when the contact portion 211a of the stylus 211 comes into contact with the measurement object S, the stylus 211 and the probe holding portion 210 move relative to the probe casing 220 before distortion occurs in the stylus 211 and the probe holding portion 210. At this time, a change in the output of the displacement amount data obtained by the magnetic sensor 270 represents a change in the positional relationship between the stylus 211 and the probe holding portion 210 and the probe casing 220. Therefore, based on the degree of change in the positional relationship between the stylus 211 and the probe holding portion 210 and the probe casing 220, the displacement amount data can appropriately determine the timing for indicating a measurement point so as not to cause excessive distortion in the stylus 211 and the probe holding portion 210. As a result, it is possible to calculate the coordinates of the measurement point on the measurement object S with high accuracy regardless of the rigidity of the stylus 211 and the probe holding portion 210.

[0218] (2) In the probe 200 described above, the magnet 260 and the magnetic sensor 270 are used to detect the amount of displacement of the probe holding part 210 relative to the probe casing 220. The magnetic sensor 270 makes it possible to detect the amount of displacement of the probe holding part 210 relative to the probe casing 220 regardless of the direction of the displacement. In this case, it is not necessary to prepare multiple displacement meters for detecting displacements corresponding to multiple directions. Therefore, an increase in the number of parts of the probe 200 is suppressed.

[0219]

[10] Example of using Probe Camera 208 By capturing an image of the measurement target S with the probe camera 208 in Fig. 13, the image of the measurement target S can be displayed on the main body display unit 310 in Fig. 3. Hereinafter, the image obtained by the probe camera 208 will be referred to as a captured image.

[0220] The positional relationship between the multiple markers eq of the probe 200 and the probe camera 208, and the characteristics of the probe camera 208 (angle of view, distortion, etc.) are stored in advance as imaging information in, for example, the main body memory 303 of Fig. 3. Therefore, when the multiple markers eq are within the imaging field of view of the movable camera 120, the area imaged by the probe camera 208 is recognized by the main body control circuit 302 of Fig. 3. In other words, the three-dimensional space corresponding to the captured image is recognized by the main body control circuit 302. In this case, the captured image can be displayed on the main body display unit 310 while superimposing the geometric elements and measurement items set when measuring the measurement target S.

[0221]

[11] Preferred Features (1) Preferred selection function for measurement point coordinate calculation processing As described above, in the measurement point coordinate calculation process, the process of step S103 in Fig. 23 may be omitted. Here, the operating state of the main body control circuit 302 when the series of processes in Fig. 23 are executed is called the first instruction mode, and the operating state of the main body control circuit 302 when the series of processes in Fig. 23 excluding the process of step S103 are executed is called the second instruction mode.

[0222] The three-dimensional coordinate measuring device 1 preferably has an instruction mode selection function that enables the operation of the main body control circuit 302 to be selected between a first instruction mode and a second instruction mode, for example, based on the operation of the main body operation unit 320 by the user U. In this case, the user U can easily select the operation mode of the main body control circuit 302 between the first instruction mode and the second instruction mode according to his or her preference.

[0223] When the operating state of the main body control circuit 302 is in the first instruction mode, the user U brings the contact portion 211a into contact with a desired portion of the measurement target S, and operates the probe operation portion 221 while the contact portion 211a is in contact with the measurement target S. This causes the measurement point to be specified.

[0224] On the other hand, when the operating state of the main body control circuit 302 is in the second instruction mode, the user U brings the contact portion 211a into contact with a desired portion of the measurement target S. This causes the processing of step S104 to be performed in response to a contact trigger output from the probe 200, thereby specifying a measurement point. In this way, according to the second instruction mode, the user U does not need to operate the probe operation portion 221 when specifying a measurement point.

[0225] (2) Screen operation function using Probe 200 As described above, the user U can set the desired measurement conditions and then measure the desired physical quantity of the measurement target S. To set the desired measurement conditions, the user U selects geometric elements and measurement items. A screen for selecting the geometric elements and measurement items is displayed on the main body display unit 310 (FIG. 3), for example, as a measurement screen. The user U then operates the main body operation unit 320 (FIG. 3) to select the geometric elements and measurement items on the measurement screen of the main body display unit 310.

[0226] 26 is a diagram showing an example of a measurement screen displayed on the main body display unit 310 at the initial stage of measurement of the measurement target S. On the measurement screen ms, the display area of ​​the main body display unit 310 is divided into a measurement status display area 311, a result display area 312, and an operation display area 313.

[0227] As shown in Figure 26, the measurement status display area 311 displays an image (hereinafter referred to as a measurement area virtual image) VI that virtually represents the area in which the coordinates of the measurement point can be calculated by the three-dimensional coordinate measuring device 1, in other words, the area in which the dimensions of the measurement object S can be measured by the three-dimensional coordinate measuring device 1.

[0228] In the three-dimensional coordinate measuring device 1, the x-axis and y-axis of the device coordinate system are set parallel to and perpendicular to a flat, horizontal virtual floor surface, and the z-axis of the device coordinate system is set perpendicular to the floor surface. The measurement area virtual image VI in FIG. 26 includes the x-axis, y-axis, and z-axis of the device coordinate system as well as a floor image FI corresponding to the virtual floor surface. Furthermore, it also includes an image (hereinafter referred to as a probe image) PI1 indicating the position and orientation of the probe 200 in the device coordinate system. Information indicating the position and orientation of the probe 200 can be acquired by the measurement point coordinate calculation process described above. Thus, by visually checking the measurement area virtual image VI, the user U can easily grasp the position and orientation of the probe 200 in the device coordinate system.

[0229] The result display area 312 is an area that mainly displays the measurement results. Therefore, in the initial stage of the measurement, no information is displayed in the result display area 312. The operation display area 313 is an area that displays at least one of icons and buttons to be operated by the user U and a display field showing predetermined information.

[0230] Specifically, as shown in the dotted line frame, the operation display area 313 in Fig. 26 displays a plurality of item icons i01 (two in this example) corresponding to a plurality of predetermined measurement items. In this example, the two item icons i01 correspond to the measurement items "distance" and "angle," respectively.

[0231] Additionally, the operation display area 313 displays a plurality of element icons i02 (19 in this example) corresponding to a plurality of predetermined geometric elements, as shown within a dashed-dotted frame. The plurality of element icons i02 include a plurality of element icons i02 corresponding to the geometric elements "plane," "straight line," "circle," "point," "cylinder," "cone," and "sphere." Furthermore, the plurality of element icons i02 include a plurality of element icons i02 corresponding to the geometric elements "rounded rectangle," "ellipse," "quadrilateral," "stepped cylinder," "torus," "midpoint," "intersection point," "tangent line," "median line," "intersection line," "intersection circle," and "median plane."

[0232] The user U can select an element icon i02 indicating a desired geometric element from a plurality of element icons i02 by operating the main body operation unit 320 of Fig. 3. The user U can also select an item icon i01 indicating a desired measurement item from a plurality of item icons i01 by operating the main body operation unit 320 of Fig. 3. Furthermore, if the three-dimensional coordinate measuring device 1 has an instruction mode selection function as described above, the user U can select a desired instruction mode for the operating state of the main body control circuit 302 by operating the main body operation unit 320 of Fig. 3.

[0233] However, if the distance between the measurement object S and the main body operation unit 320 is large, the user U cannot simultaneously use the probe 200 to indicate a measurement point and the main body operation unit 320 to select a geometric element, a measurement item, and an instruction mode in one place. In this case, the user U must frequently move between the measurement object S and the main body operation unit 320 when measuring the measurement object S. Frequent movement of the user U between the measurement object S and the main body operation unit 320 significantly reduces the measurement efficiency of the measurement object S. Therefore, the three-dimensional coordinate measuring device 1 according to this embodiment may have a screen operation function that enables the probe 200 to be used to select a geometric element, a measurement item, and an instruction mode. An example of the screen operation function is described below.

[0234] (3) Screen transition examples using screen operation functions In the following explanation, of the four push buttons 221b shown in Fig. 15, the roughly rectangular push button 221b will be referred to as the upper button. Of the remaining three push buttons 221b, the push button 221b farthest from the upper button will be referred to as the lower button. Furthermore, when viewing the operation surface 221a so that the upper and lower buttons are positioned one above the other, the two push buttons 221b positioned left and right between the upper and lower buttons will be referred to as the left and right buttons.

[0235] In a three-dimensional coordinate measuring device 1 having a screen operation function, the up button, down button, left button, and right button of the probe 200 are used as operation buttons for selecting one of multiple types of buttons or icons displayed on the main body display unit 310. In addition, the trigger switch 221c shown in Fig. 14 is used as an appropriate decision button.

[0236] 27 is a diagram showing an example of the measurement screen ms when the screen operation function is activated during measurement of the measurement target S. The screen operation function is activated by the user U pressing and holding for about two seconds any one of the multiple push buttons 221b (for example, the up button) of the probe operation unit 221. Note that the screen operation function may also be activated by pressing and holding the trigger switch 221c (FIG. 14) instead of the up button.

[0237] When the screen operation function is activated, a selection setting window 314 for setting screen operations by the probe 200 is superimposed on the measurement screen ms as shown in Fig. 27. In the selection setting window 314, an instruction mode setting button 315 and an element item setting button 316 are displayed lined up vertically in this order.

[0238] The instruction mode setting button 315 is a button for setting an instruction mode using the probe 200. The element item setting button 316 is a button for selecting a geometric element and a measurement item using the probe 200. One of the instruction mode setting button 315 and the element item setting button 316 (in this example, the instruction mode setting button 315) is surrounded by a cursor frame indicating that the button is selected. In the selection setting window 314 in FIG. 27, the cursor frame is indicated by a thick dotted line. The user U can move the cursor frame between the instruction mode setting button 315 and the element item setting button 316 by operating the up button and down button of the probe operation unit 221.

[0239] When the user U wishes to select an instruction mode, he or she operates the up button and down button to move the cursor frame over the instruction mode setting button 315. At this time, the trigger switch 221c of the probe operation unit 221 functions as a confirmation button. Therefore, the user U operates the trigger switch 221c with the cursor frame positioned over the instruction mode setting button 315. In this case, the selection setting window 314 is changed to an instruction mode selection window that allows the user U to select either the first instruction mode or the second instruction mode.

[0240] Fig. 28 is a diagram showing an example of a measurement screen ms on which an instruction mode selection window is superimposed. In the instruction mode selection window 317 of Fig. 28, a first instruction mode button 318 and a second instruction mode button 319 are displayed aligned vertically in this order.

[0241] The first instruction mode button 318 is a button for setting the operating state of the main body control circuit 302 to the first instruction mode. The second instruction mode button 319 is a button for setting the operating state of the main body control circuit 302 to the second instruction mode. One of the first instruction mode button 318 and the second instruction mode button 319 (in this example, the first instruction mode button 318) is surrounded by a cursor frame indicating that the button is selected. In the instruction mode selection window 317 of FIG. 28, the cursor frame is indicated by a thick dotted line. The user U can move the cursor frame between the first instruction mode button 318 and the second instruction mode button 319 by operating the up button and down button of the probe operation unit 221.

[0242] When the user U wishes to set the operating state of the main body control circuit 302 to the first instruction mode, the user U operates the up button and down button to move the cursor frame over the first instruction mode button 318. At this time, the trigger switch 221c of the probe operation unit 221 functions as a confirmation button. Therefore, the user U operates the trigger switch 221c with the cursor frame moved over the first instruction mode button 318. This sets the operating state of the main body control circuit 302 to the first instruction mode.

[0243] On the other hand, if the user U wishes to set the operating state of the main body control circuit 302 to the second instruction mode, the user U operates the up button and down button to move the cursor frame over the second instruction mode button 319. Furthermore, the user U operates the trigger switch 221c with the cursor frame positioned over the second instruction mode button 319. This sets the operating state of the main body control circuit 302 to the second instruction mode.

[0244] 27 is displayed on the measurement screen ms of the main body display unit 310, the user U operates the up button and down button to move the cursor frame to the element item setting button 316 when he or she wants to select a geometric element and a measurement item. At this time, the trigger switch 221c of the probe operation unit 221 functions as a confirmation button. Therefore, the user U operates the trigger switch 221c with the cursor frame moved to the element item setting button 316. In this case, the selection setting window 314 disappears from the measurement screen ms. Furthermore, it becomes possible to select a geometric element and a measurement item using the probe 200.

[0245] 29 is a diagram showing an example of the display of the measurement screen ms when it becomes possible to select geometric elements and measurement items using the probe 200. When it becomes possible to select geometric elements and measurement items, a cursor frame is displayed in the operation display area 313 of the measurement screen ms. The displayed cursor frame surrounds any one of the multiple item icons i01 and multiple element icons i02 displayed in the operation display area 313. In the operation display area 313 of FIG. 29, the cursor frame is indicated by a thick dotted line.

[0246] By operating the up button, down button, left button, and right button of the probe operation unit 221, the user U can move the cursor frame between the multiple item icons i01 and the multiple element icons i02, as shown by the outlined arrows in Fig. 29. At this time, the trigger switch 221c of the probe operation unit 221 functions as a confirmation button. Then, the user U operates the trigger switch 221c with the cursor frame positioned on an icon corresponding to a desired geometric element or a desired measurement item. This selects the geometric element or measurement item corresponding to the icon on which the cursor frame is positioned.

[0247] In this way, the user U can select the desired geometric element and the desired measurement item by operating the probe operation unit 221 of the probe 200 without using the main body operation unit 320.

[0248] A specific example will be described below. For example, as explained in the measurement example in item [5] above, when it is desired to measure the distance between the first surface and the second surface of the measurement target S, the user U operates the probe operation unit 221 to select the item icon i01 corresponding to the geometric element "plane."

[0249] Thereafter, measurement points are specified by contacting the contact portion 211a with multiple portions on the first surface of the measurement target S. As a result, element identification information of a plane specified by the multiple measurement points specified on the first surface is generated as, for example, "plane 1."

[0250] Fig. 30 is a diagram showing an example of the measurement screen ms when multiple measurement points are specified after selecting a geometric element. As shown in Fig. 30, when the geometric element "plane" is selected, an element name field f01, an image capture button b01, a switch button b02, and a measurement point coordinate display field f02 are displayed in the operation display area 313 of the measurement screen ms.

[0251] The element name field f01 displays a name for storing the element-specific information generated for the selected geometric element in an identifiable manner, according to a predetermined method. In this example, "Plane 1" is displayed.

[0252] The imaging button b01 is a button for capturing an image of the measurement object S by the probe camera 208 of Fig. 13 provided on the probe 200. When the imaging button b01 is operated, the measurement object S is captured by the probe camera 208. Image data obtained by capturing the image is stored in the main body memory 303 as captured image data.

[0253] The switching button b02 is a button for switching the image displayed in the measurement status display area 311 between the above-mentioned measurement area virtual image VI and a captured image obtained by operating the imaging button b01. Specific display examples of the captured image in the measurement status display area 311 will be described later. When a measurement point is designated, an indicator such as a black dot indicating the coordinate position of the designated measurement point is superimposed on the measurement area virtual image VI or the captured image displayed in the measurement status display area 311. Furthermore, an image indicating a geometric element specified by the multiple measurement points is superimposed on the image.

[0254] The measurement point coordinate display field f02 is a display field for sequentially displaying the coordinates of the measurement points acquired by the measurement point designation operation. In this example, four measurement points are specified to set the first surface of the measurement target S as the measurement target portion. As a result, the coordinates of the four measurement points are displayed in the measurement point coordinate display field f02.

[0255] The operation display area 313 of the measurement screen ms also displays a back button b11, an OK button b12, and a cancel button b13. The back button b11 is a button for returning the state of the three-dimensional coordinate measuring device 1 to the state in which the measurement screen ms of FIG. 26 or 27 is displayed on the main body display unit 310 so that the selection operation of the geometric element and measurement item can be accepted. The OK button b12 is a button for instructing the three-dimensional coordinate measuring device 1 that the specification of all measurement points for the selected geometric element has been completed. This generates element identification information for the selected geometric element based on the specified one or more measurement points. The cancel button b13 is a button for deleting the measurement point information acquired by the measurement point specification operation.

[0256] When the screen operation function is activated, a cursor frame is displayed for selecting one of the multiple buttons displayed in the operation display area 313. In the example of Fig. 30, the cursor frame is indicated by a thick dotted line so as to surround the OK button b12. The user U can move the cursor frame among the imaging button b01, the switching button b02, the back button b11, the OK button b12, and the cancel button b13 by operating the up button, down button, left button, and right button of the probe operation unit 221.

[0257] 29, element identification information corresponding to, for example, the first and second surfaces of the measurement object S is generated by repeatedly selecting geometric elements and specifying measurement points on the measurement screen ms. Furthermore, element identification information corresponding to another surface (third surface) of the measurement object S is generated.

[0258] After element identification information corresponding to each of the first to third surfaces of the measurement object S has been generated, the user U selects the measurement item "distance" on the measurement screen ms of Figure 29 to measure the distance between the first and second surfaces.

[0259] FIG. 31 is a diagram showing an example of the measurement screen ms after a measurement item has been selected. If the measurement item "distance" is selected after element identification information corresponding to the first to third surfaces has been generated, it must be specified that the "distance" is the distance between the first and second surfaces. Therefore, in the example of FIG. 31, three target buttons b20 representing element identification information corresponding to the first to third surfaces, respectively, are displayed in the operation display area 313. A back button b11 is also displayed.

[0260] When the screen operation function is activated, a cursor frame is displayed to select one of the multiple buttons displayed in the operation display area 313. In the example of FIG. 31, the cursor frame is indicated by a thick dotted line. The user U can move the cursor frame among the multiple target buttons b20 and the back button b11 by operating the up button, down button, left button, and right button of the probe operation unit 221. The user U can also confirm the selection of the button over which the cursor frame is positioned by operating the trigger switch 221c of the probe operation unit 221. The user U then specifies "Plane 1" corresponding to the element identification information of the first surface and "Plane 2" corresponding to the element identification information of the second surface. As a result, the distance (measured value) between the first and second surfaces of the measurement target S is displayed on the measurement screen ms, as shown in the result display area 312 of FIG. 31.

[0261] As described above, with the screen operation function, the user U can set the measurement conditions and specify the measurement points for the measurement object S by operating the probe 200 without using the main body operation unit 320. This improves the efficiency of measuring the measurement object S.

[0262] (4) Switching the image displayed in the measurement status display area 311 As described above, when the user U captures an image of the measurement object S using the probe camera 208 by operating the imaging button b01 in Figure 30, he or she can further operate the switch button b02 to display the captured image in the measurement status display area 311.

[0263] 32 is a diagram showing an example of the measurement screen ms when a captured image is displayed in the measurement status display area 311. In the example of FIG. 32, a captured image SI of the measurement target S is displayed in the measurement status display area 311. Furthermore, the x-axis, y-axis, and z-axis of the device coordinate system are superimposed on the captured image SI based on the above-mentioned imaging information so as to correspond to the three-dimensional space represented by the captured image SI. Furthermore, a stylus image PI2 is superimposed on the captured image SI as an image corresponding to the probe image PI1 in FIG. 29. The stylus image PI2 represents the position and orientation of the contact portion 211a of the stylus 211 of the probe 200 and the vicinity thereof.

[0264] When the image displayed in the measurement status display area 311 is switched from the measurement area virtual image VI to the captured image SI, the index indicating the position and orientation of the probe 200 is switched between the probe image PI1 and the stylus image PI2.

[0265] The measurement area virtual image VI basically represents the entire measurable space, but does not include an image that virtually represents the measurement object S itself. Therefore, even if the user U refers to the measurement area virtual image VI, he or she cannot grasp the position and orientation of the measurement object S in the device coordinate system. In this embodiment, when the measurement area virtual image VI is displayed in the measurement status display area 311, a probe image PI1 that shows the entire probe 200 is also displayed. This allows the user U to easily recognize, based on the content displayed in the measurement status display area 311, whether the position and orientation of the probe 200 are within the measurable range of the measurement object S in the three-dimensional coordinate measuring device 1.

[0266] Here, assume a case where the user U captures an image and indicates a measurement point at a fixed position relative to the measurement target S. As described above, in the probe 200 according to this embodiment, the probe camera 208 is attached to the front end 251 (FIG. 14) of the main body 250. The imaging field of the probe camera 208 is directed in the first direction dr1. Therefore, in the above case, when the user U captures an image of the measurement target S using the probe camera 208, it is considered that the captured image SI obtained by the image capture includes an image of the part of the measurement target S that should be indicated as the measurement point.

[0267] When a probe image PI1 showing the entire probe 200 is superimposed on a captured image SI obtained by imaging, there is a high possibility that at least a portion of the probe image PI1 will overlap an image of a portion of the measurement object S that should be designated as a measurement point. In FIG. 32, the display range of the probe image PI1 expected when the probe image PI1 is superimposed on the captured image SI is indicated by a dashed-dotted line frame. In this case, even if the user U visually recognizes the captured image SI, he or she will not be able to recognize the image of the desired portion of the measurement object S. Therefore, in this embodiment, when the captured image SI is displayed in the measurement status display area 311, a stylus image PI2 showing only a portion of the stylus 211 is superimposed on the captured image SI. This reduces the possibility that the image of the probe 200 (particularly the image of the main body 250) will overlap most of the captured image SI. This allows the user U to easily grasp the position and attitude of the probe 200 (stylus 211) relative to the measurement object S by visually recognizing the image displayed in the measurement status display area 311. Therefore, the user U can visually view the surface of the measurement object S with the naked eye and, while viewing the captured image SI displayed in the measurement status display area 311, can indicate the measurement point with high accuracy for the desired part of the measurement object S.

[0268] In the probe 200 according to this embodiment, the orientation of the grip part 230 relative to the main body part 250 can be switched in a plurality of stages. This increases the degree of freedom of the position and orientation of the user U relative to the measurement object S. Therefore, the range of the portion of the measurement object S that can be imaged by the probe camera 208 is also increased. In this case, an image of the tip of the stylus 211 (stylus image PI2) is displayed compactly on the captured image SI, and therefore, as the degree of freedom of the position and orientation of the probe 200 that can be placed relative to the measurement object S increases, a decrease in visibility of the measurement point in the captured image SI is suppressed.

[0269] (5) Functional configuration of the main body control circuit 302 for measurement operations FIG. 33 is a block diagram showing the functional configuration of the main body control circuit 302 related to operations for measurement. As shown in FIG. 33, the main body control circuit 302 includes, as functional components related to operations for measurement, a display control unit 302a, an instruction mode selection receiving unit 302b, an element selection receiving unit 302c, and a contact part image switching unit 302d. In this example, in addition to the above-mentioned system program, measurement processing program, and tracking processing program, an operation program corresponding to the screen operation function is stored in the main body memory 303. As a result, each functional unit shown in FIG. 33 is realized by the CPU of the main body control circuit 302 executing the operation program stored in the main body memory 303.

[0270] In response to operation of the probe operation unit 221 or the main body operation unit 320 by the user U, the display control unit 302a causes the main body display unit 310 to display a measurement screen ms (Figures 28 to 32) including a measurement status display area 311, a result display area 312, and an operation display area 313.

[0271] The instruction mode selection receiving unit 302b receives an instruction as to whether the operating state of the main body control circuit 302 is to be set to the first or second instruction mode in response to operation of the probe operation unit 221 or the main body operation unit 320 by the user U.

[0272] The element selection receiving unit 302c receives the selection of geometric elements or measurement items corresponding to the multiple item icons i01 and multiple element icons i02 displayed in the operation display area 313 in response to the user U's operation of the probe operation unit 221 or the main body operation unit 320.

[0273] The contact part image switching unit 302d accepts switching of the image to be displayed in the measurement status display area 311 in response to operation of the probe operation unit 221 or the main body operation unit 320 by the user U, while the captured image data is stored in the main body memory 303. The contact part image switching unit 302d also displays the accepted image in the measurement status display area 311. Furthermore, when the measurement area virtual image VI is displayed in the measurement status display area 311, the contact part image switching unit 302d also superimposes and displays a probe image PI1 on the measurement area virtual image VI. On the other hand, when the captured image SI is displayed in the measurement status display area 311, the contact part image switching unit 302d also superimposes and displays a stylus image PI2 on the captured image SI.

[0274] 2. Second embodiment Fig. 34 is a schematic diagram showing an example of the configuration of a three-dimensional coordinate measuring system according to the second embodiment. As shown in Fig. 34, a three-dimensional coordinate measuring system 700 according to this embodiment includes a probe operating robot 600 in addition to the three-dimensional coordinate measuring device 1 according to the first embodiment. Note that Fig. 34 does not show a reference stand 900 for fixing the imaging head 100 on the floor surface.

[0275] In the three-dimensional coordinate measuring system 700, the imaging head 100 is arranged so that the imaging field of the movable camera 120 covers at least the measurement target S placed on the floor surface, for example, and the area around it.

[0276] The probe manipulation robot 600 includes a robot operating unit 610 and a robot main body 620. The robot operating unit 610 is mainly composed of an articulated arm 611 and a probe gripping mechanism 612. The articulated arm 611 is provided to extend from the robot main body 620. The probe gripping mechanism 612 is provided at the tip of the articulated arm 611. The probe gripping mechanism 612 is connected to the probe 200.

[0277] FIG. 35 is a block diagram showing the basic configuration of the probe 200 of FIG. 34. As shown in FIG. 35, in this embodiment, a robot connector 257 is connected to the probe casing 220. The robot connector 257 is provided with a fixing element 257a for fixing the probe gripping mechanism 612 and the robot connector 257. The fixing element 257a is, for example, a female screw, and the probe gripping mechanism 612 and the robot connector 257 are fixed by the screw. In this embodiment, since the user U does not carry the probe 200, it is preferable that the gripping part 230 is detachable from the probe casing 220. The example of FIG. 34 shows the probe 200 in a state where the gripping part 230 is detached from the probe casing 220. When the gripper 230 is not removed from the probe casing 220, it is preferable that the gripper 230 and the robot connector 257 are arranged so that at least the gripper 230 does not interfere with the fixation of the probe gripping mechanism 612 and the robot connector 257. Furthermore, the gripper 230 may rotate around the rotation axis RA (FIG. 14, etc.) and move to a position where it does not interfere with the fixation of the robot connector 257 and the probe gripping mechanism.

[0278] Furthermore, the probe 200 of this embodiment accommodates a probe communication circuit 258 in the probe casing 220. As shown in FIG. 34 , the probe 200 and the processing device 300 are connected by a communication cable CAa. The probe 200 and the processing device 300 communicate with each other via the probe communication circuit 258 and the cable CAa. A contact trigger output by the probe control unit 201 is transmitted from the probe communication circuit 258 to the processing device 300 through the cable CAa. The cable CAa is, for example, a USB (Universal Serial Bus) cable. When the gripper 230 is detached from the probe casing 220, power may be supplied to the probe 200 via the cable CAa.

[0279] As shown in a speech bubble in Fig. 34, the robot main body 620 incorporates a robot driving unit 621, a communication unit 622, and a robot control unit 623. The robot driving unit 621 includes a plurality of motors and the like, and drives the articulated arm 611. The robot control unit 623 includes, for example, a CPU and memory, or a microcomputer, and controls the robot driving unit 621. The robot main body 620 is connected to the imaging head 100 via a communication cable CAb. The robot control unit 623 can exchange various data with the imaging head 100, the probe 200, and the processing device 300 via the communication unit 622 and the cable CAb.

[0280] An encoder (not shown) is provided at each joint of the articulated arm 611. The robot control unit 623 controls the robot driving unit 621 based on, for example, predetermined coordinate information on the measurement object S and the output of the encoder at each joint of the articulated arm 611. Thereby, for example, the contact portion 211a of the probe 200 is brought into contact with a desired portion of the measurement object S.

[0281] FIG. 36 is a block diagram showing the configurations of the imaging head 100 and the processing device 300 in FIG. 34. As shown in FIG. 36, the imaging head 100 is connected to the communication circuit 170 and includes an external I / O 175 for outputting signals to an external device. The external I / O 175 is, for example, a terminal block, to which the cable CAb in FIG. 34 is connected. The signal output from the external I / O 175 to the robot control unit 623 via the cable CAb includes, for example, a signal based on a contact trigger output from the probe 200. With this configuration, the imaging head 100 outputs a binary signal having a High output and a Low output to the robot control unit 623. Therefore, the imaging head 100 can output a signal to the robot control unit 623 in which the contact trigger output from the probe 200 corresponds to the rising or falling edge of the binary signal. Therefore, with the imaging head 100 of this embodiment, a three-dimensional coordinate measuring system 700 can be constructed in which the control of the robot driving unit 621 by the robot control unit 623 is highly responsive.

[0282] As described above, the contact trigger output from the probe 200 is transmitted to the processing device 300 through the cable CAa. Furthermore, the contact trigger or a signal based on the contact trigger is transmitted from the processing device 300 to the probe-operating robot 600 through the cable CA, the imaging head 100, and the cable CAb. In this case, the robot control unit 623 controls the robot driving unit 621 in response to the contact trigger output from the probe 200 so that the operation of the robot operating unit 610 is temporarily stopped. Furthermore, the main body control circuit 302 of the processing device 300 commands the emission of light from multiple markers eq ( FIG. 14 ) and ep ( FIG. 10(b) ) of the probe 200 and the imaging head 100 in response to the contact trigger.

[0283] According to the above operation, while the probe 200 in contact with the measurement target S is temporarily stopped, images of the multiple markers eq (FIG. 14) of the probe 200 are captured by the movable camera 120 of the imaging head 100. Therefore, it becomes possible to calculate the coordinates of the measurement point indicated by the probe 200 with high accuracy.

[0284] Note that, instead of a contact trigger, displacement amount data may be transmitted from the probe 200 to the probe-operating robot 600. In this case, the robot control unit 623 may determine that the contact unit 211a of the probe 200 has properly contacted the measurement target S by executing, for example, processes similar to steps S203, S204, S207, and S208 (FIG. 24) of the contact trigger output process. Then, when the robot control unit 623 determines that the contact unit 211a has properly contacted the measurement target S, it may control the robot driving unit 621 to temporarily stop the operation of the robot operating unit 610.

[0285] In the above-described three-dimensional coordinate measuring system 700, the probe-operating robot 600 operates based on the contact trigger or displacement amount data output from the probe 200 so as not to cause excessive distortion in the stylus 211 and the probe holder 210. More specifically, since it is determined in step S208 that the difference between the magnetic reference value, which is appropriately updated based on the determination at each step, and the current displacement amount data is equal to or less than the fourth threshold value, excessive distortion is unlikely to occur in the stylus 211 and the probe holder 210. Furthermore, the timing for designating a measurement point is appropriately determined. As a result, the coordinates of the measurement point designated by the probe-operating robot 600 are calculated with high accuracy.

[0286] 3. Other embodiments (1) In the above embodiment, the magnet 260 and the magnetic sensor 270 are provided in the probe 200 to detect the amount of displacement of the probe holding part 210 relative to the probe casing 220, but the present invention is not limited to this. Instead of the magnet 260 and the magnetic sensor 270, the probe 200 may be provided with another configuration capable of detecting the amount of displacement between the probe casing 220 and the probe holding part 210. As such a configuration, for example, an optical sensor or an ultrasonic sensor capable of measuring the amount of displacement can be used.

[0287] (2) In the above embodiment, the output of the motion sensor 207 is used to determine whether the movement and posture of the probe 200 are appropriate for indicating a measurement point in steps S202 and S205 of the contact trigger output process, but the present invention is not limited to the above example. Whether the movement and posture of the probe 200 are appropriate for indicating a measurement point may be determined, for example, by continuously capturing images of multiple markers eq on the probe 200 using the movable camera 120 or the overhead camera 180, and based on changes in their movement speed and positional relationship.

[0288] (3) In the above embodiment, the contact trigger output process is executed by the probe control unit 201 of the probe 200, but the present invention is not limited to this. In the probe 200, movement data and posture data obtained by the motion sensor 207 may be transmitted to the processing device 300 through the imaging head 100. Furthermore, displacement amount data obtained by the magnetic sensor 270 may be transmitted to the processing device 300 through the imaging head 100. In these cases, the main body control circuit 302 of the processing device 300 may execute the contact trigger output process based on the movement data, posture data, and displacement amount data provided by the probe 200. Alternatively, the above contact trigger output process may be executed by the head control circuit 150 of the imaging head 100 instead of the probe control unit 201 of the probe 200.

[0289] (4) In the probe 200 according to the above embodiment, the magnetic sensor 270 is fixed to the probe-holding section 210 and the magnet 260 is fixed to the probe casing 220. However, the present invention is not limited to this. The magnet 260 may be fixed to the probe-holding section 210 and the magnetic sensor 270 may be fixed to the probe casing 220.

[0290] (5) In each display example of the measurement screen ms shown in Figures 27 to 32, the currently selected button among multiple buttons that can be selected by the probe operation unit 221 is surrounded by a cursor frame, but the present invention is not limited to this. The button currently selected by the probe operation unit 221 may be displayed so as to be distinguishable from other unselected buttons. For example, instead of or in addition to adding a cursor frame to the currently selected button, the button may be displayed in a different display mode from the other buttons by highlighting or emphasizing, etc.

[0291] (6) In the above embodiment, the captured image SI is displayed in the measurement status display area 311 by operating the imaging button b01 and the switching button b02 shown in Fig. 30, but the present invention is not limited to this. In place of the measurement area virtual image VI and the captured image SI, or in addition to the measurement area virtual image VI and the captured image SI, an image based on existing dimensional data such as CAD (Computer Aided Design) data (hereinafter referred to as an existing data image) may be displayed in the measurement status display area 311. When the existing data image is displayed in the measurement status display area 311, a stylus image PI2 may be displayed on the existing data image together with the x-axis, y-axis, and z-axis of the device coordinate system.

[0292] (7) Although the stylus image PI2 in Fig. 32 is displayed superimposed on the captured image SI so as to include an image of the contact portion 211a and its surrounding area of ​​the stylus 211, the present invention is not limited to this. The stylus image PI2 may be displayed superimposed on the captured image SI so as to include only an image of the contact portion 211a.

[0293] (8) In each display example of the measurement screen ms shown in Figures 26 to 31, the scale (the range of space in the device coordinate system represented by the measurement area virtual image VI) of the measurement area virtual image VI displayed in the measurement status display area 311 may be changeable. In this case, one of the probe image PI1 and the stylus image PI2 may be selectively superimposed and displayed on the measurement area virtual image VI depending on the size of the space represented by the measurement area virtual image VI.

[0294] (9) In the above embodiment, the probe operation unit 221 of the probe 200 includes four push buttons 221b arranged in a cross shape on the operation surface 221a, but the present invention is not limited to this. The operation surface 221a of the probe operation unit 221 may be provided with another pointing device, such as a trackball or a pointing stick, that can be operated by the user U while holding the grip portion 230, instead of or in addition to the four push buttons 221b.

[0295] 4. Correspondence between each element of the claims and each part of the embodiment Below, examples of correspondence between each component of the claims and each part of the embodiment will be described, but the present invention is not limited to the following examples.

[0296] In the above embodiment, the three-dimensional coordinate measuring device 1 is an example of a three-dimensional coordinate measuring device, the probe 200 is an example of a probe, the multiple markers eq of the probe 200 are an example of multiple measurement markers, the movable camera 120 is an example of an imaging unit, the probe holding unit 210 is an example of a holding unit, the contact unit 211a is an example of a contact unit, the stylus 211 is an example of a stylus, the probe casing 220 is an example of a probe casing, the multiple rubber bushings rb are an example of an elastic body, and the magnet 260 and the magnetic sensor 270 are examples of a displacement sensor.

[0297] Furthermore, the contact trigger is an example of a trigger signal, the magnetic reference value is an example of a reference displacement amount, the probe control unit 201 is an example of a probe control unit and a condition setting unit, above the third threshold and below the fourth threshold is an example of a predetermined tolerance range, the motion sensor 207 is an example of a movement detection unit and an attitude detection unit, the magnetic sensor 270 is an example of a magnetic sensor, the gripping unit 230 is an example of a gripping unit, the main body control circuit 302 is an example of a calculation unit, the robot operation unit 610 and the robot drive unit 621 are examples of a robot, the robot control unit 623 is an example of a robot control unit, and the three-dimensional coordinate measuring system 700 is an example of a three-dimensional coordinate measuring system.

[0298] Various other elements having the configuration or function described in the claims may also be used as each component of the claims. [Explanation of symbols]

[0299] 1...three-dimensional coordinate measuring device, 9...machining machine, 900...reference stand, 20...fixed connecting part, 21...lower fixed plate, 22...upper fixed plate, 23...support, 24...hollow support shaft, 30...support member, 30c, RA...rotating shaft, 31...rotating base, 32, 33...support frame, 40...movable member, 41...upper surface, 42...lower surface, 43, 111, 121, 181...board, 50...bellows, 90...casing, 91, 220b...lower casing, 91W...window for overhead camera, 92, 220a...upper casing, 92S...rectangular opening, 93...board casing, 93a, 93b...accommodating section, 100...imaging head, 101...head bottom, 102...annular bottom surface, 103,832...annular inclined surface, 104...opening, 105,833...vertical hole, 110...reference camera, 110c,120c...optical axis, 120...movable camera, 130,204...marker drive circuit, 140...rotation drive circuit, 141...horizontal rotation mechanism, 143...tilt rotation mechanism, 150...head control circuit, 160,206...wireless communication circuit, 170,301...communication circuit, 175...external I / O, 180...overhead camera, 190...reference member, 191...light-emitting substrate, 192...diffusion plate, 193...glass plate, 194...mask, 195...diffuse reflection sheet 200... probe, 201... probe control unit, 202... indicator light, 202a... first display unit, 202b... second display unit, 203... battery, 205... probe memory, 207... motion sensor, 208... probe camera, 210... probe holding unit, 210a... stylus mounting unit, 210b... target member holding unit, 211... stylus, 211a... contact unit, 220... probe casing, 221... probe operation unit, 221a... operation surface, 221b... push button, 221c... trigger switch, 230, 230x... gripping unit, 250... main body unit, 251... front end portion, 2 52...rear end portion, 253...top surface portion, 254...bottom surface portion, 254h...hinge, 254j...connection portion, 255...one side portion, 256...other side portion, 257...robot connection portion, 257a...fixing element, 258...probe communication circuit, 260...magnet, 270...magnetic sensor, 290...target member, 299...opening, 300...processing device, 302...main body control circuit, 302a...display control unit, 302b...instruction mode selection receiving unit, 302c...element selection receiving unit, 302d...contact portion image switching unit, 303...main body memory, 310...main body display unit, 311...measurement status display area, 312...result display area,313...operation display area, 314...selection setting window, 315...instruction mode setting button, 316...element item setting button, 317...instruction mode selection window, 318...first instruction mode button, 319...second instruction mode button, 320...main body operation unit, 600...probe operation robot, 610...robot operation unit, 611...articulated arm, 612...probe gripping mechanism, 620...robot main body unit, 621...robot drive unit, 622...communication unit, 623...robot control unit, 700...three-dimensional coordinate measuring system, 800...holding unit, 810...installation unit, 820...mounting table, 830, 911...head base, 831...annular support surface, 912...legs, b01...imaging button, b02...switching button, b11...back button, b12...OK button b13...Cancel button, b20...Target button, ca...Color, CA, CAa, CAb...Cable, CB...Cross roller bearing, EC...Power cable, ep, ep1, ep2, eq...Marker, FI...Floor image, f01...Element name field, f02...Measurement point coordinate display field, GS...Heat generating board, h1, h2, h3...Through hole, HA1, LA1...Intake section, HA2, LA2...Exhaust section, HF, LF...Exhaust fan, hi1...Hollow member, hi2...Shaft member, i01...Item icon, i02...Element icon, ms...Measurement screen, PI1...Probe image, PI2...Stylus image, rb...Rubber bushing, rs...Image capture space, S...Measurement object, SI...Image capture, sc...Screw, U...User, VI...Virtual image of measurement area, Wa, Wb...Weight

Claims

1. A probe used in a three-dimensional coordinate measuring device that calculates coordinates of a measurement point on a measurement object based on a plurality of measurement markers captured by an imaging unit, a probe holder that holds the plurality of measurement markers; a stylus having a contact portion that indicates the measurement point by contacting the measurement object, and that is attached to the probe holder in a predetermined positional relationship with the plurality of measurement markers; a probe casing that accommodates at least a portion of the probe holding portion so that the plurality of measurement markers can be imaged from the outside; an elastic body that is housed in the probe casing and is arranged between the probe casing and the probe holding portion so that the probe holding portion is displaced relative to the probe casing in response to contact between the stylus and the measurement object; a displacement sensor housed in the probe casing and configured to output a signal corresponding to the amount of displacement of the probe holding portion relative to the probe casing as a signal relating to contact between the stylus and the object to be measured.

2. 2. The probe for a three-dimensional coordinate measuring device according to claim 1, further comprising: a probe control unit that outputs a trigger signal permitting the start of processing for calculating coordinates of the designated measurement point when a predetermined reference condition is satisfied for a displacement amount corresponding to an output signal of the displacement sensor when the measurement point is designated.

3. further comprising a condition setting unit for setting the reference condition, the reference condition is that a difference between a displacement amount corresponding to a signal output from the displacement sensor and a reference displacement amount is within a predetermined allowable range; 3. The probe for a three-dimensional coordinate measuring device according to claim 2, wherein the condition setting unit sets a displacement amount corresponding to a signal output from the displacement sensor at a certain time point as the reference displacement amount, and updates the reference displacement amount with the displacement amount corresponding to the signal output from the displacement sensor after a predetermined time has elapsed from the certain time point.

4. a movement detection unit that detects movement of the probe casing; 4. The probe for a three-dimensional coordinate measuring device according to claim 2, wherein the probe control unit outputs the trigger signal when an amount of movement per unit time detected by the movement detection unit is equal to or less than a first threshold value, and does not output the trigger signal when the amount of movement per unit time detected by the movement detection unit is greater than the first threshold value.

5. a posture detection unit for detecting the posture of the probe casing; 5. The probe for a three-dimensional coordinate measuring device according to claim 4, wherein the probe control unit outputs the trigger signal when an amount of change in posture per unit time detected by the posture detection unit is equal to or less than a second threshold value, and does not output the trigger signal when the amount of change in posture per unit time detected by the posture detection unit is greater than the second threshold value.

6. 6. The probe for a three-dimensional coordinate measuring apparatus according to claim 1, wherein the displacement sensor includes a magnetic sensor.

7. 7. The probe for a three-dimensional coordinate measuring apparatus according to claim 1, wherein a grip portion that can be held by a user is connected to the probe casing.

8. A probe for a three-dimensional coordinate measuring apparatus according to any one of claims 1 to 7; an imaging unit that images a plurality of measurement markers of the probe based on an output signal of the displacement sensor; a calculation unit that calculates coordinates of the measurement point indicated by the contact unit based on image data representing images of the plurality of measurement markers captured by the imaging unit.

9. a three-dimensional coordinate measuring device that calculates coordinates of a measurement point on a measurement object based on a plurality of measurement markers captured by an imaging unit; a probe including the plurality of measurement markers; a robot configured to be able to hold and move the probe; a robot control unit; The probe is a probe holder that holds the plurality of measurement markers; a stylus having a contact portion that indicates the measurement point by contacting the measurement object, and that is attached to the probe holder in a predetermined positional relationship with the plurality of measurement markers; a probe casing that is held by the robot and that accommodates at least a part of the probe holding portion so that the plurality of measurement markers can be imaged from outside; an elastic body that is housed in the probe casing and is arranged between the probe casing and the probe holding portion so that the probe holding portion is displaced relative to the probe casing in response to contact between the stylus and the measurement object; a displacement sensor that is housed in the probe casing and outputs a signal corresponding to a displacement amount of the probe holding portion relative to the probe casing as a signal related to contact between the stylus and the measurement object; a probe control unit that outputs a trigger signal that permits starting a process for calculating coordinates of the designated measurement point when a predetermined reference condition is satisfied for a displacement amount corresponding to an output signal of the displacement sensor when the measurement point is designated, the robot control unit controls the operation of the robot based on the output of the displacement sensor; The three-dimensional coordinate measuring device is an imaging unit that images a plurality of measurement markers of the probe when the trigger signal is output from the probe control unit; a calculation unit that calculates coordinates of the measurement point indicated by the contact unit based on image data representing images of the plurality of measurement markers captured by the imaging unit.

10. A three-dimensional coordinate measurement method for calculating coordinates of a measurement point on a measurement object using a probe, comprising: The probe is a probe holder that holds a plurality of measurement markers; a stylus having a contact portion that indicates the measurement point by contacting the measurement object, and that is attached to the probe holder in a predetermined positional relationship with the plurality of measurement markers; a probe casing that accommodates at least a portion of the probe holding portion so that the plurality of measurement markers can be imaged from the outside; an elastic body that is housed in the probe casing and is arranged between the probe casing and the probe holding portion so that the probe holding portion is displaced relative to the probe casing in response to contact between the stylus and the measurement object; a displacement sensor that is housed in the probe casing and outputs a signal corresponding to a displacement amount of the probe holding portion relative to the probe casing as a signal related to contact between the stylus and the measurement object, The three-dimensional coordinate measuring method includes: a step of outputting a trigger signal that permits starting a process for calculating the coordinates of the designated measurement point when a predetermined reference condition is satisfied for a displacement amount corresponding to an output signal of the displacement sensor when the measurement point is designated; capturing an image of the plurality of measurement markers in response to the output of the trigger signal, and calculating coordinates of the measurement point indicated by the contact portion based on image data representing the captured image of the plurality of measurement markers.

11. further comprising a step of setting the reference condition; the reference condition is that a difference between a displacement amount corresponding to a signal output from the displacement sensor and a reference displacement amount is within a predetermined allowable range; 11. The three-dimensional coordinate measuring method according to claim 10, wherein the step of setting the reference condition includes setting a displacement amount corresponding to a signal output from the displacement sensor at a certain time point as the reference displacement amount, and updating the reference displacement amount by the displacement amount corresponding to the signal output from the displacement sensor after a predetermined time has elapsed from the certain time point.

12. detecting movement of the probe casing; 12. The three-dimensional coordinate measuring method according to claim 10, wherein the step of outputting the trigger signal is performed when the amount of movement per unit time detected by the step of detecting movement is equal to or less than a first threshold value, and is not performed when the amount of movement per unit time detected by the step of detecting movement is greater than the first threshold value.

13. further comprising detecting the attitude of the probe casing; 13. The three-dimensional coordinate measuring method according to claim 12, wherein the step of outputting the trigger signal is performed when an amount of change in the posture per unit time detected by the step of detecting the posture is equal to or less than a second threshold value, and is not performed when the amount of change in the posture per unit time detected by the step of detecting the posture is greater than the second threshold value.

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