JP2015190818A - Work support device, work support system, work support method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work support system for supporting improvement of work efficiency to total work completion.SOLUTION: The work support system includes: a measuring device for measuring three-dimensional shape data of an object to be measured; a moving device for moving at least either the object to be measured or the measuring device to change a measurement position of the object to be measured by the measuring device; and a work support device for controlling the moving device. The work support device includes: a candidate position setting section for setting a measurement position to be a candidate to an entire area of a measurement target range that is designated as the measurement target range in a surface of the object to be measured; a possible surface calculating section for calculating the number of surfaces of the object to be measured which can be measured, or an area for each of the set measurement positions; a prioritizing section for determining priorities of measurement in accordance with the calculated number of surfaces or area for each measuring direction; and a measurement control section which instructs the moving device to perform the measurement in each of the measuring directions in accordance with the determined priorities.

Description

  The present invention relates to a work support device, a work support system, a work support method, and a program.

In order to measure the surface shape of the measuring object, a non-contact three-dimensional measuring machine is used. In general, a non-contact three-dimensional measuring machine measures the distance to a target surface using the principle of triangulation, and images a target object with one camera, and laser light is applied to the target from a different position. A means for irradiating or irradiating an object with projection light is used (light projection method). In another method, an object is imaged with one camera, and a means for imaging with another camera from a different position is used (stereo camera method). In the light projection method, the projection is more vivid as the traveling direction of the projected light is perpendicular to the projected surface. Further, the image is captured more clearly as the direction of the line of sight of the camera to be imaged is perpendicular to the surface to be imaged. Because such a method is used, in the light projection method, a single measurement makes a shadow (dead angle) of some obstacle, the surface that is not illuminated, the surface that cannot be imaged (occlusion), or the angle of the surface is far away from the vertical. Therefore, a surface that is not clearly irradiated or a surface that is not clearly imaged is a surface that is not measured. That is, the surface that can be measured in one measurement operation is only a surface that is clearly irradiated by laser irradiation or projection light, and that light can be clearly captured by the camera.
When the shape of the measurement object is complicated, occlusion often occurs in one measurement operation, and it is necessary to make it possible to measure this occlusion occurrence portion by moving the apparatus to another position. As described above, the measurement operation is performed a plurality of times, and the selection of the measurement position and the movement of the measurement apparatus are generally performed manually by a person.
Moreover, the measurement data of the whole object are obtained by connecting and synthesizing a plurality of surface shape data obtained by a plurality of measurement operations. If the positional relationship between the target object and the measuring device when measuring the surface shape data is quantitatively understood, the data can be automatically joined. It is necessary to specify the relative position of this by human hand as well.
Thus, in the measurement of a complex shape object, if a plurality of positional relationships between the object and the measuring device can be automatically calculated, measurement by position movement using an automatic stage or an automatic robot can be performed, and the movement position By using the information, it becomes possible to automate the joining of data.

  On the other hand, for example, Patent Document 1 discloses that reference is made to design information and CAD information of an object to be measured in order to support three-dimensional measurement and other various measurements.

  In Patent Document 2, surface shape dimensions are accurately measured by obtaining three-dimensional position information of a non-contact displacement meter on a measurement path corresponding to a plurality of measurement points set on the surface of an object to be measured. An apparatus is disclosed. However, since this method is intended for a non-contact measuring device that measures the distance between a certain point of the object to be measured and the device, it takes a tremendous amount of time to measure the object to be measured at high density as in this case. Because it takes, it is not suitable for practical use.

  Patent Document 3 discloses a three-dimensional measurement system that determines whether or not a site is not measurable based on CAD data and specification information of a three-dimensional measuring device. However, in this system, only a local solution is given, and the efficiency of the overall work cannot be expected.

JP 2002-328952 A Japanese Examined Patent Publication No. 7-18698 JP 2007-3285 A

  An object of the present invention is to provide a work support device that supports the efficiency of work toward the completion of overall work.

  In order to solve the above problem, the work support device of the present invention is a candidate position that sets candidate work positions for the entire work target range specified as the work target range on the surface of the work target. For each of the work positions set by the candidate position setting unit, a setting unit, a possible surface calculation unit that calculates the number or area of the surfaces of work objects that can be worked on, and a surface calculated by the possible surface calculation unit And a determination unit that determines a combination of work positions based on the number or area.

  Preferably, the work is a measurement work of three-dimensional shape data, and the candidate position setting unit sets a measurement direction as at least the work position with respect to the entire circumference of the measurement target range of the measurement target, The possible surface calculation unit calculates the number or area of surfaces capable of measuring a three-dimensional shape for each set measurement direction based on the design information of the measurement object, and the determination unit calculates A combination of measurement directions is determined based on the number or area of the surfaces.

  Preferably, the candidate position setting unit sets only candidate measurement directions for the entire circumference of the measurement object, and the possible surface calculation unit is capable of measuring each set measurement direction. A rank determining unit that determines the priority of measurement according to the calculated number or area of surfaces for each measurement direction, and the determining unit includes the rank determining unit The combination of the measurement directions is determined based on the priority order determined by the above and the allowable number of measurements or measurement time.

  Preferably, the candidate position setting unit sets only candidate measurement directions for the entire circumference of the measurement object, and the possible surface calculation unit is capable of measuring each set measurement direction. In accordance with the priority determined by the rank determination unit, the rank determination unit that determines the priority of measurement according to the calculated number or area of the surface for each measurement direction, A measurement control unit for instructing measurement in each measurement direction;

  Preferably, based on the design information of the measurement object and the specification information of the three-dimensional shape measurement apparatus, it is impossible to identify an impossible surface that cannot be measured from any measurement direction set by the candidate position setting unit. The possible surface calculation unit further excludes the impossible surface specified by the impossible surface specification unit from the surface in the measurement target range of the measurement object, and the impossible surface is excluded. The number or area of measurable surfaces is calculated for each measurement direction with respect to the surface of the measurement target range.

  Preferably, a random number is used to further include a condition changing unit that replaces a part of the combination of the measurement directions provisionally determined by the determination unit with another measurement direction, and the determination unit includes the provisionally determined combination. And the combination changed by the condition changing unit to determine the combination of measurement directions to be adopted.

  In addition, the work support system according to the present invention includes a measurement device that measures three-dimensional shape data of a measurement object, and at least one of the measurement object and the measurement device is moved so that the measurement object is measured by the measurement device. And a work support device that controls the mobile device, and the work support device includes a whole area of the measurement target range designated as the measurement target range on the surface of the measurement target. A candidate position setting unit for setting a candidate measurement position, and a possible surface calculation for calculating the number or area of the surface of the measurement object that can be measured for each of the measurement positions set by the candidate position setting unit. And a rank determining unit that determines the priority of measurement according to the number or area of the surfaces calculated by the possible surface calculating unit for each measurement direction, and the rank determining unit According to the determined priority Ri, and a measurement control section for instructing the mobile device to measure in each measurement direction.

  Further, the work support method according to the present invention includes a candidate position setting step of setting candidate work positions for the entire work target range designated as the work target range among the surfaces of the work target; For each work position set by the candidate position setting step, based on the possible surface calculation step for calculating the number or area of the surface of the work target that can be worked on, and the number or area of the surface calculated by the possible surface calculation step And a determination step for determining a combination of work positions.

  Further, the program according to the present invention includes a candidate position setting step for setting a candidate work position for the entire work target range designated as the work target range on the surface of the work target, and the candidate position For each work position set by the setting step, based on the possible surface calculation step for calculating the number or area of the surface of the work target that can be worked on, based on the number or area of the surface calculated by the possible surface calculation step, A determination step for determining a combination of work positions;

  ADVANTAGE OF THE INVENTION According to this invention, the work assistance apparatus which assists the efficiency improvement of the work toward the completion of the whole work can be provided.

It is a figure for demonstrating the outline | summary of the work assistance system 2 concerning embodiment. 2 is a diagram illustrating a functional configuration of a work support program 11 installed in the work support apparatus 10. FIG. It is the figure which illustrated the division | segmentation to the equal 128 pieces of the direction in three-dimensional space. It is a flowchart explaining work assistance processing (S10). It is a figure explaining the relationship between the irradiation direction of the laser irradiated from the laser irradiation port 5a of the measuring apparatus 5, and the light reception direction of the camera 5b of the measuring apparatus 5. FIG. It is a figure explaining the relationship of the irradiation position of a laser of the measuring apparatus 5, and a light reception direction, and a measurement position. It is a figure which illustrates local optimization and global optimization. It is a figure which illustrates STL data of a measuring object valve body. It is a figure which illustrates the irradiation conditions of the measuring apparatus. It is a figure which illustrates a light reception irradiation coincidence condition table. It is a figure which illustrates a surface data consideration table. It is a figure which illustrates a visible surface / invisible surface table. It is a figure which illustrates the visible surface / invisible surface table for calculating a co-visible surface. It is a figure which shows the result of a demonstration experiment.

(background)
First, the background of the present invention will be described.
As described above, in the measurement work using the non-contact three-dimensional measuring apparatus, the position of the apparatus and the measurement object is determined by the operator's experience, and the measurement object is installed and moved by the operator's hand. It has been broken. Therefore, when the measurement object has a complicated shape, even a skilled worker sometimes performs a plurality of measurements while performing trial and error. In addition, it is difficult for an inexperienced worker to determine an efficient measurement position. Moreover, it is difficult to measure from the same position as the measurement three months ago for the same measurement object. In non-contact 3D measurement equipment, even if the measurement object is the same, if the measurement position is different, the measurement error may be different. It is important to measure the shape error in manufacturing.
As described above, waste of trial and error and the root cause of measurement from different positions for each measurement are because determination of the measurement position depends on the experience of the operator.

  An object of the present invention is to perform a work simulation on a three-dimensional work object within a range of required time allowed for practical use, and to complete the entire work based on the simulation result. Here, the completion of the overall work means that the work is completed in the widest possible area of the work object within an allowable time rather than the local complete solution. Specifically, in measurement of a measurement object using a three-dimensional measuring device, the operator can automatically and totally discriminate between a portion that can be measured by the three-dimensional measuring device and a portion that is not. To reduce the time and effort required for measurement.

  In the above-mentioned Patent Document 3, in measurement of a measurement object using a three-dimensional measuring machine, the time required for measurement is determined by automatically determining a measurable part and a non-measurable part instead of an operator. And a system for reducing labor is presented. However, this system is not intended to complete the overall work, nor is it aware of the time required for practical use. For example, with respect to the definition of the angle, it is described that the measurement limit direction LIMIT is defined by adding α which is a scalar quantity to the normal vector n. The limit direction LIMIT cannot be uniquely defined. That is, it is not conscious of the entire three-dimensional work object. In addition, the determination of the measurement position is not efficient, and is a technique that is highly likely to fall into local optimization.

The work support system of the present embodiment described below supports the work to be completed efficiently over the widest possible range of the three-dimensional measurement object (work object) within a practically allowable time range. It is characterized by an overall and efficient simulation and an optimization algorithm that does not fall into local optimization.
In the following embodiment, measurement work of three-dimensional shape data will be described as a specific example of work. For example, the work to be supported may be a painting work on a three-dimensional object.

(Work support system)
FIG. 1 is a diagram for explaining an overview of a work support system 2 according to the embodiment.
As illustrated in FIG. 1, the work support system 2 includes a measuring device 5, a moving device 6, and a work support device 10.
The measuring device 5 is a three-dimensional measuring device that measures three-dimensional shape data of the measurement object 9. The measuring device 5 measures the three-dimensional shape data of the measuring object 9 in accordance with the specifications (measurable distance, measurable angle, etc.) regarding the three-dimensional measurement. The measuring device 5 measures the shape of the measurement object in a non-contact manner. For example, as shown in FIG. 1, the laser beam is scanned from the upper part 5a onto the measurement object, and the state is observed by the camera 5b at the lower part. By imaging and triangulating, measuring the surface shape of a part of the measurement object, performing such measurement from various directions with respect to the measurement object, and combining the obtained measurement results, It is an apparatus for measuring the shape of the entire necessary part of the measurement object. In addition, the laser irradiation and camera light-receiving part of the measuring device 5 may be not only those vertically divided as shown in FIG.

  The moving device 6 moves at least one of the measurement object 9 and the measurement device 5 to change the measurement position of the measurement object 9 by the measurement device 5. The moving device 6 of this example includes a moving device 6A that moves the measuring device 5 and a moving device 6B that moves the measuring object 9. The moving device 6A has an arm portion and a cart portion, and horizontally moves and rotates the measuring device 5 in the three-dimensional direction, and the moving device 6B has a cart portion and horizontally moves the measurement object 9.

  The work support device 10 controls the measurement device 5 and the moving device 6 to support the measurement work of the three-dimensional shape data. Specifically, the work support device 10 includes specification information (such as a measurable distance and measurable angle) of the measuring device 5, specification information (such as a movable range) of the moving device 6, and design information of the measuring object 9. (CAD data) is registered, and based on such information, measurement work is simulated to determine a combination of measurement positions, and measurement is performed so that actual measurement is performed at the determined measurement positions. The device 5 and the moving device 6 are controlled.

In addition, in order to measure the external shape of a certain measurement object, the positional relationship between the measurement object 9 and the measurement apparatus 5 is, for example, when the measurement object 9 is fixed at a certain position in a three-dimensional space. The positional relationship can be determined by six variables of a relative position [X, Y, Z] from the object and a rotational position [Yaw, Pitch, Roll]. In the following description, for the sake of convenience, a method of mainly fixing the measurement object 9 and moving the measurement apparatus 5 is adopted. However, in actual measurement, even if the measurement apparatus 5 is moved or the measurement object 9 is moved, Either one does not matter.
The relative positional relationship P between the measuring object 9 and the measuring device 5 can be uniquely determined by six variables P [X, Y, Z, Yaw, Pitch, Roll]. For example, the measuring object 9 is placed in an arbitrary posture at the origin position in the three-dimensional space. At this time, the range of X, Y, Z, which is a variable of the position P of the measuring device 5, depends on the measurable distance of the measuring device 5 and the size of the measuring object 9, for example, -1m to + 1m, respectively. It is assumed that -180 degrees to +180 degrees, Pitch is in the range of -90 degrees to +90 degrees, and Roll is in the range of -180 degrees to +180 degrees. Within this range, it is possible to calculate which surface is visible by simulation, assuming a number of positions P of the measuring device 5. Assuming, for example, that the measurement object 9 is measured 20 times by the measuring device 5, the first position is P1, the second position is P2, the twentieth position is P20, and [P1, P2,. ] Can be defined, and this is Pset. The work support apparatus 10 sets the combination Pset having the largest measurement area as an optimal measurement position set for 20 measurements. In order to calculate this, the work support device 10 can equally divide the six position parameters into a finite number within a possible range, and calculate the total number of each. However, in this method, when the number of equally dividing a certain range is small, the calculation accuracy is deteriorated. Further, if the number of divisions is increased in order to increase the calculation accuracy, the calculation amount becomes enormous and does not end within a finite time.
Therefore, this work support system 2 employs a technique of increasing the calculation accuracy while suppressing the calculation amount without performing brute force by equal division of all six position variables. One of the features of this method is the use of orthographic projection. In a normal three-dimensional space, the actual camera line of sight is a three-dimensional projection method that radiates from a certain point. In this method, when the distance between the measurement object 9 and the measurement device 5 changes, the way the camera looks is changed. Since it is different, it is necessary to calculate at each distance, and the calculation amount increases. On the other hand, when the orthographic projection method is used, the appearance of the camera is constant regardless of the distance to the measurement object 9, and thus the amount of calculation can be suppressed. This method will also be described later.

FIG. 2 is a diagram illustrating a functional configuration of the work support program 11 installed in the work support apparatus 10. The work support apparatus 10 is a computer terminal in which the work support program 11 is installed.
As illustrated in FIG. 2, the work support program 11 includes a candidate position setting unit 100, a possible surface calculation unit 102, an impossible surface identification unit 104, a determination unit 106, a priority order determination unit 108, and a condition change Unit 110 and measurement control unit 112.
The work support program 11 is recorded on a recording medium such as a CD-ROM, and is installed in the work support apparatus 10 via this recording medium. The work support program 11 of this example is a computer program, but is not limited to this, and a part or all of the work support program 11 may be realized by hardware such as an ASIC.
In addition, the work support apparatus 10 includes a specification information database 120 and a design information database 122. The specification information database (specification information DB) 120 stores the specification information of the measuring device 5 and the specification information of the moving device 6. The design information database (design information DB) 122 stores design information (for example, CAD data) of the measurement object 9. The design information DB 122 of this example stores STL format shape data formed by a plurality of polygons.

The candidate position setting unit 100 sets the measurement direction as a measurement position candidate for the entire circumference of the measurement target range of the measurement object 9. For example, regarding the measurement object 9, the candidate position setting unit 100 accepts designation of a range to be measured by user input, and sets the measurement direction as a candidate for the entire circumference of the designated measurement target range.
The candidate position setting unit 100 in this example defines the direction in the three-dimensional space with two parameters φ and θ, and sets all directions divided into a plurality of (φ, θ) as measurement direction candidates. To do. At this time, φ and θ can be divided at regular intervals within a range of, for example, + 180 ° to −180 ° or + 90 ° to −90 °. However, since unevenness occurs in the polar regions, an equal dividing method is used. You can also. For example, when the candidate position setting unit 100 is equally divided into 128 pieces as shown in FIG. 3, each direction is defined as D1 to D128 and set as a measurement direction candidate. The angle resolution can be increased by increasing the number of divisions to 518 or 2048.

The possible surface calculation unit 102 calculates the number or area of surfaces on which the three-dimensional shape can be measured for each measurement direction set by the candidate position setting unit 100 based on the design information of the measurement object 9. For example, the possible surface calculation unit 102 is set by the candidate position setting unit 100 based on the design information of the measurement object 9 stored in the design information DB 122 and the specification information stored in the specification information DB 120. The measurable area is calculated from each measurement direction.
The possible surface calculation unit 102 of the present example includes the camera focal length and depth of field, the camera field of view range (X direction and Y direction), the distance between the irradiation unit and the camera light receiving unit, and laser light irradiation. When a parameter (specification data) such as a range (X direction, Y direction) is taken into consideration, when a light is received (imaged) from a certain direction Dr so that the point is located at the center of the camera image, a certain direction Di Whether or not the laser can be irradiated is determined, and a table in which the light receiving direction Dr (Dr1 to Dr128) is arranged vertically and the irradiation direction Di (Di1 to Di128) is arranged horizontally is created. ) And stored as a received light irradiation coincidence condition table (FIG. 10). Further, the possible surface calculation unit 102 generates the tables of FIGS. 11 to 13 in consideration of the surface state of the measurement object, and calculates a measurable area from each measurement direction.

The impossible surface specifying unit 104 specifies an impossible surface that cannot be measured from any measurement direction set by the candidate position setting unit 100 based on the design information of the measurement object 9 and the specification information of the measuring device 5. To do.
The impossible surface specifying unit 104 of this example uses ray tracing to determine whether a certain surface has a shielding object when viewed from a certain direction, and specifies an invisible surface that cannot be measured from any measurement direction.

Based on the area of each measurement direction calculated by the possible surface calculation unit 102, the determination unit 106 determines a combination of measurement directions to be adopted from candidate measurement directions. For example, the priority order determination unit 108 determines the priority order of the measurement direction as a candidate based on the area of each measurement direction calculated by the possible surface calculation unit 102, and the determination unit 106 uses the priority order determination unit 108. A combination of measurement directions to be employed is determined based on the determined priority order and the allowable number of measurements or measurement time.
The determining unit 106 of this example determines a combination of measurement directions that maximizes the total measurable area using an optimization algorithm described later.

For example, the priority order determination unit 108 determines the priority order of the measurement direction in order of increasing area of each measurement direction calculated by the possible surface calculation unit 102.
The condition changing unit 110 replaces a part of the combination of measurement directions determined by the determination unit 106 with other measurement directions based on random numbers, and evaluates the increase or decrease of the total measurable area, Optimize the combination of measurement methods that maximizes the measurable area. As illustrated in FIG. 7, when the determination unit 106 determines a combination of measurement directions by a predetermined method, there is a possibility that the determination unit 106 falls into a local optimum (left side in FIG. 7). A combination that maximizes the possible area is provisionally determined, and part of the provisionally determined combination is changed by the condition changing unit 110 to search for an optimized combination (right side in FIG. 7).

  The measurement control unit 112 controls the moving device 6 based on the combination of measurement directions determined by the determination unit 106. For example, the measurement control unit 112 places the measurement device 5 in each measurement position (measurement direction) on the moving device 6 according to the order determined by the priority order determination unit 108 among the combinations of measurement directions determined by the determination unit 106. Move in order.

(Work support method)
FIG. 4 is a flowchart for explaining the work support process (S10).
As shown in FIG. 4, in step 12 (S12), the candidate position setting unit 100 reads CAD data (STL data) of the measurement object 9 from the design information DB 122, and accepts designation of the measurement target range.
The candidate position setting unit 100 sets candidate measurement directions over the entire measurement target range of the specified measurement target. The measurement direction to be set is divided by a division method with an equal area.

  In step 14 (S14), the impossible surface specifying unit 104 specifies and specifies an impossible surface (invisible surface) that cannot be measured from any of the measurement directions set by the candidate position setting unit 100 by ray tracing. An impossible surface (invisible surface) is notified to the possible surface calculation unit 102.

  In step 16 (S16), the possible surface calculation unit 102 determines the candidate position based on the specification information of the measuring device 5, the design information of the measurement object, and the impossible surface specified by the impossible surface specifying unit 104. An area that can be measured in each measurement direction set by the setting unit 100 is calculated.

In step 18 (S18), the priority order determination unit 108 determines the priority order of each measurement direction based on the measurable area of each measurement direction calculated by the possible surface calculation unit 102. The priority increases as the measurable area increases.
The determination unit 106 temporarily determines a combination of measurement directions based on the priority determined by the priority determination unit 108 and the allowable number of measurements or measurement time.

In step 20 (S20), the condition changing unit 110 generates a random number and replaces a part of the combination temporarily determined in S18 with another measurement direction according to the random number.
In step 22 (S22), the determination unit 106 makes a comparison based on the measurable area between the combination of the measurement directions partially replaced and the combination of the temporarily determined measurement directions. Adopt a wide combination.
In the work support process (S10), when the processes of S20 and S22 are repeated a predetermined number of times, the process proceeds to S26.

  In step 26 (S26), the measurement control unit 112 moves the mobile device 6 and the measurement device 5 based on the combination of the measurement directions determined by the determination unit 106 and the priority determined by the priority determination unit 108. And control to measure the three-dimensional shape of the measurement object with the determined priority from the measurement direction of the determined combination.

(Detailed processing contents and result verification)
-Preparation of target shape data In order to perform efficient measurement, prepare target object shape data (CAD data). It is important how to import this shape data into the work support apparatus 10 and perform a simulation calculation to determine an efficient measurement position of the measurement apparatus. Here, the case where the shape data of the measurement object is in the STL format formed by a plurality of polygons is targeted. Such STL data is generally created at the design stage in order to manufacture a measurement object. For example, the STL data of the measurement target valve body shown in FIG. 8 is composed of 59,240 triangular polygon surfaces. Its surface area is 82858 mm ² . It is sufficient if all surfaces can be measured. However, since an invisible surface (invisible surface) such as the inner surface of the tube is generated, the work support apparatus 10 first separates the measurable surface from the unmeasurable surface and performs measurement. The procedure is to determine how to measure the possible surface efficiently.

-Direction division The direction in the three-dimensional space is defined by two parameters φ and θ. In addition, the candidate position setting unit 100 sets all directions divided into a plurality of (φ, θ) as measurement direction candidates. At this time, φ and θ can be divided at equal intervals within a range of, for example, + 180 ° to −180 ° or + 90 ° to −90 °. However, since unevenness occurs in the polar regions, an equal dividing method is used. It can also be used. For example, if it is equally divided into 128, each direction can be divided into D1 to D128. The angle resolution can be increased by increasing the number of divisions to 512, 2048, or the like.

・ Creation of matching table for received light irradiation conditions The measuring device 5 includes a focal length and a depth of field of the camera, a visual field range of the camera (X direction and Y direction), a distance between the irradiation unit and the camera light receiving unit, and laser light irradiation. There are parameters (specification data) such as ranges (X direction, Y direction). The possible surface calculation unit 102 considers the parameters (specifications) of the measurement device 5 and, as illustrated in FIG. 5A, the point is positioned at the center of the camera image from a certain direction Dr with respect to a certain point. When light is received (imaged), it is determined whether the laser can be irradiated from a certain direction Di. The possible surface calculation unit 102 creates a table in which the light receiving direction Dr (Dr1 to Dr128) is arranged vertically and the irradiation direction Di (Di1 to Di128) is arranged horizontally, as illustrated in FIG. / X) is stored, and a received light irradiation coincidence condition table is generated.
When the angle between the light receiving direction and the irradiation direction is small, the measurement distance is separated as shown in FIG. 6B, and when the angle is large, the measurement distance is approached as shown in FIG. 6C. For example, when the camera light receiving direction is Dr1, considering the parameter conditions of the measuring device 5, the angle formed by Dr1 and Di2 is small in order to set the laser irradiation direction to Di2. As shown, the measuring device 5 is arranged far away. Since there is only one measurement position that satisfies Dr1 and Di2, if the determination unit 106 can determine these two measurement directions, the six parameters [X, Y, Z, Yaw indicating the relative position of the measurement device 5 with respect to a certain point are determined. , Pitch, Roll] can be uniquely determined. Similarly, in Dr1 and Di3, since the angle formed by the two directions is large, as shown in FIG.
Also, there is a range that can be arranged at the angle formed by Dr and Di. Assuming that the range is 5.7 ° to 22.6 °, the angle between Dr and Di is as shown in FIG. 9, and the angle condition (O) that the measuring device 5 can take is Di2, Di3, Di4. There are only four of Di5, and the others are position conditions (x) that the measuring apparatus 5 cannot take.
Similarly, when the same evaluation as Dr2 and Dr3 is performed, the result is as shown in FIG. The possible surface calculation unit 102 can determine this table only with the parameters (specification data) of the measuring device 5.

Evaluation for Each Surface Subsequently, the possible surface calculation unit 102 performs evaluation for each surface in the shape data of the measurement object. Since the surface is represented by a triangular polygon, it has three-dimensional coordinates of each vertex. By calculating the center point of each vertex, the center coordinates of the surface can be calculated. Moreover, there are front and back, and has surface normal direction information on the front side.

-Consideration of surface data The possible surface calculation unit 102 considers the surface state of the measurement object. With respect to the state of the surface of the measurement object, the intensity distribution in a certain direction of the reflected light can be obtained by experiments or the like when the incident angle of the light is many times from the direction perpendicular to the surface. This is called diffuse reflection characteristics. Based on this characteristic, the possible surface calculation unit 102 can reflect the amount of light measurable by the camera with respect to the reflection direction Dr when light is incident on the first surface F1 from the incident direction Di. Determine. Further, the possible surface calculation unit 102 considers the irradiation / light reception simultaneous condition shown in FIG. 10 before this determination, and if the simultaneous condition is not satisfied in the table of FIG. 10, the surface is not visible without considering the surface data. Since it can be determined, the calculation time is shortened.
The possible surface calculation unit 102 makes a determination for only the conditions marked with “◯” in the table of FIG. 10 among all directions from Dr1 to Di128 for the first surface F1. If the result is visible, the possible surface calculation unit 102 embeds a circle in the table relating to the surface F1 and sets the remainder as x to be the surface data consideration table in FIG.

-Creation of Visible Surface / Invisible Surface Table by Ray Tracing The invisible surface specifying unit 104 determines whether a certain surface has a shielding object when viewed from a certain direction using ray tracing. The invisible surface specifying unit 104 determines the invisible surface by checking the presence or absence of interference using the ray tracing method in the directions of D1 to D128 for the first surface F1. As a result of the determination, all the elements of Dr and Di in the direction where there is interference are invisible (x).
Here, in the table of FIG. 11, in order to determine that the direction of Di where all the items are x and all the items are x, the direction of Di is not visible without considering the result of ray tracing. It leads to shortening of calculation time.
The invisible surface specifying unit 104 embeds the results of ○ and × in the table of received light irradiation by determining by ray tracing for all directions from D1 to D128 for the first surface F1, and visible in FIG. / Invisible surface table.
The invisible surface specifying unit 104 determines all surfaces from F1 to F59240 in all directions from D1 to D128.

As described above, it is possible to create as many tables as the number of the surfaces in which the determination results indicating which surface can receive light from which direction and from which direction the light can be measured can be measured. The circles indicate the light receiving direction and the irradiation direction for measuring the corresponding surface. The center coordinates of the surface are calculated by calculating the center of gravity of the vertex, and when two directions are determined, six relative position parameters [X, Y, Z, Yaw, Pitch, Roll] are determined. Thus, the position parameter of the measuring device 5 with respect to the measurement object is determined.
In this table, the surface with no surface number is not visible. Thereby, the visible surface and the invisible surface could be extracted from the surface to be measured.
Next, a method for specifying how to measure efficiently among the surfaces that can be measured by somehow (efficiency of measurement work) will be described.

-Calculation of co-visible surface with respect to visible condition (circle) About the certain surface F, among Di and Dr 1-128, the surface where all are x is an invisible surface. When there is even one circle, it indicates that the surface can be measured by irradiating from the Di direction and receiving light from the Dr direction. The possible surface calculation unit 102 counts all the numbers of ○, sets the number to k, and represents the visibility condition ○ as E (Enable). As shown in FIG. Shake.
In general, the Di and Dr tables on the surface F, which is the visible surface, should have a plurality of Es. If one condition is extracted from the conditions with a plurality of E, the measurement position P [X, Y, Z, Yaw, Pitch, Roll] of the measuring device 5 that satisfies the irradiation direction Di and the light receiving direction Dr at that En is obtained. Determined uniquely. Further, if the measurement position P [X, Y, Z, Yaw, Pitch, Roll] of the measurement device 5 is uniquely determined, it is determined by simulation which surface is visible among F1 to F59240 under the measurement position condition. Is possible. The surface that can be measured simultaneously when measuring En is called a co-visible surface under the measurable condition En, and the possible surface calculation unit 102 uses an array to determine which surface is co-visible in the AFn (Accompanyy Face) array. Store. The total area of the co-visible surfaces is SA (SumArea). In the first measurable condition E1, if the surfaces of surface numbers 2, 3, 4, and 5 are co-visible and the total area is 100 mm2, the possible surface calculation unit 102 determines that AF1 = {2, 3, 4 , 5} and SA1 = 100.

-Reduction of measurement condition E In the above method, E is generated in the number of measurable ○. When the number of measurement conditions is large, the amount of calculation for determining the measurement order increases. Therefore, all the ○ s in a certain visible surface F, which are performed in the procedure of “calculation of co-visible surface for visible conditions ○”, are represented by E The possible surface calculation unit 102 stores, in the array, the best condition for measuring the visible surface Fn as En, and the co-visible surface at that time as AFn, among the various Es. In this case, the total co-visible area can be set to SAn. The “best condition” here is a measurement position in a direction in which the light receiving direction is closest to the normal direction of the target surface (more precisely, the direction opposite to the normal direction). If there are a plurality of options, the measurement distance to the measurement object is the closest position between the maximum value and the minimum value.
Thereby, the number of E does not exceed the number of visible surfaces, and the amount of calculation can be suppressed.

・ Determining the device position from the actual light receiving direction and irradiation direction, and determining the co-visible surface. When the calculation was actually performed, there were 2591 invisible surfaces out of 59240 in total, and 56649 surfaces visible. Calculated. When the co-visible surfaces were calculated for the light receiving direction and the irradiation direction under the best conditions, the co-visible surfaces consisted of 9048 surfaces in total, and the area was 16508 mm 2.

-Determination of measurement order 1 (Method A: Measure from the viewpoint with the largest measurable area)
The priority determining unit 108 sets the measurement condition En having the largest co-visible area SA as the first measurement condition P1. P1 = En. A surface measured under the condition En is defined as a co-visible surface AFn, and the remaining visible surface obtained by removing AFn from the visible surface is referred to as a remaining visible surface R1. The priority order determination unit 108 calculates the co-visible surfaces for all the conditions E again with respect to the remaining visible surfaces. The priority order determination unit 108 sets the measurement condition E having the largest SA among them as the second measurement condition P2. Of all visible surfaces R1, a surface excluding the co-visible surfaces measured under the measurement conditions P1 and P2 is defined as a new remaining visible surface R2. In this way, the priority order determination unit 108 determines Pn for the permitted number of measurements.

Specifically, this is performed as follows.
Calculation Example (1) From all the surfaces 59240, it is calculated that there are 56,649 visible surfaces and 2591 invisible surfaces by the calculations so far. When determining one optimal imaging condition for each surface, there are 56649 measurement conditions, which are the same number as the visible surface, and these are designated as E1 to E56649.
(2) Calculate planes that can be measured when the measuring apparatus 5 is arranged under all the measurement conditions E1 to E56649, make those planes co-visible planes, and store them in the AF. A co-visible surface group of AF1 to AF56649 is formed. In addition, the total area of the co-visible surfaces is calculated and assigned to SA1 to SA56649.
(3) Among SA1 to SA56649, the one with the largest area is defined as the first device position P1.
(4) Out of all visible surfaces, the surface excluding the measurable surface by P1 is extracted and set as the remaining visible surface R1.
(5) Similarly to (2), among the remaining visible surface R1, the surfaces that can be measured when the measuring device 5 is arranged under all the measurement conditions E1 to E56649 except for P1 are calculated, and those surfaces are AF1 to AF1. Store in AF56649. Further, the area is assigned to SA1 to SA56649.
(6) Similarly to (3), among SA1 to SA56649, the one with the largest area is defined as the second device position P2.
(7) Hereinafter, the priority order determination unit 108 repeats (2) to (4) to determine the priority order of the measurement positions.

・ Determination of measurement order 2 (Method B Position of the device that can measure the maximum area with a limited number of times)
In the above (determination of measurement order 1), the measurement conditions Pn are determined in order from the measurement condition En having the largest co-visible area SA. For example, when Method 1 is used when the number of times of measurement is limited to 10 times, the obtained 10 measurement positions may fall into a local solution. In order to prevent this, the work support apparatus 10 uses the MCMC method (Markov chain Monte Carlo method). In the MCMC method, the first P1 to P10 are determined using the method A. Subsequently, the condition changing unit 110 randomly changes the ten measurement positions one by one according to a random number, and evaluates whether or not the measurement area has increased.

Specifically, this is performed as follows.
(1) In the first round, the determination unit 106 determines a combination of measurement positions using the method A. This is the initial state. This measurement position is P1 = a1, P2 = b1,..., P10 = j1, and this combination of states is P [a1, b1, c1, d1, e1, f1, g1, h1, i1, j1].
And Further, the area of the visible surface measured by this combination is SA [a1, b1, c1, d1, e1, f1, g1, h1, i1, j1].
And
(2) The condition changing unit 110 reselects the measurement position a1 of P1 at random (from other than a1, b1, c1,..., J1) and sets it to a2. This P [a2, b1, c1, d1, e1, f1, g1, h1, i1, j1]
Is the combination of the following measurement positions, and the area of the visible surface measured by this combination is SA [a2, b1, c1, d1, e1, f1, g1, h1, i1, j1].
And
(3) The determination unit 106 calculates a ratio r between the area of the first combination and the area of the newly assumed combination.
r = SA [a2, b1, c1, d1, e1, f1, g1, h1, i1, j1] / SA [a1, b1, c1, d1, e1, f1, g1, h1, i1, j1]
(4) Generate a uniform random number R such that 0 <= R <1.
(5) If R <r, the determination unit 106 adopts the assumed combination as a new combination, and if R> = r, rejects the assumption and adopts the previous combination as it is.
In this description, R <r, and a new combination is adopted.
P [a2, b1, c1, d1, e1, f1, g1, h1, i1, j1]
(6) Subsequently, the condition changing unit 110 reselects b1 at random (from other than a2, b1, c1,..., J1) to b2. This P [a2, b2, c1, d1, e1, f1, g1, h1, i1, j1]
Is the combination of the following measurement positions, and the area of the visible surface measured by this combination is SA [a2, b2, c1, d1, e1, f1, g1, h1, i1, j1].
And
(7) Similar to (3), the determination unit 106 calculates the area ratio r of the newly assumed combination.
r = SA [a2, b2, c1, d1, e1, f1, g1, h1, i1, j1] / SA [a2, b1, c1, d1, e1, f1, g1, h1, i1, j1]
(8) As in (4) and (5), the condition changing unit 110 generates a random number R, compares it with r, and if R <r, adopts the assumed combination as a new combination, and R> = If r, the assumption is rejected and the previous combination is used as is.
(9) Similarly to (6) to (8), the condition changing unit 110 changes the objects to be reselected at random to c1, d1,..., J1, and the determining unit 106 performs evaluation.
(10) The second round of evaluation has been completed. The determination unit 106 repeats this evaluation a plurality of times to perform a search, and sets a combination of measurement positions where imaging of the maximum area can be performed as an optimal combination.

-Verification of results The measurement position was calculated using Method A. Moreover, actual measurement was performed according to this calculation result, and the result of FIG. 14 was obtained. As shown in FIG. 14, the result was compared with the case where the measurement was performed by human hand. As shown in FIG. 14, in the conventional method (manual operation), 72.1% for 20 times and 87. An area of 6% could be measured. On the other hand, in this method, the area of 75.0% at 12 times, 83.4% at 20 times, and 86.2% at 28 times could be measured. Even if it was not an expert, the possibility of reducing the number of measurements compared to manual work was shown.
Also, the amount of calculation required to determine the combination of measurement directions was compared. In the case of the method of this embodiment, it was about 3 hours, and in the comparative example, it was about 711.9 hours (29.7 days). The posture determination includes three rotational degrees of freedom (Yaw, Pitch, Roll) and three parallel movements (X, Y, Z). In this embodiment,
128 × 128 → 16,384 directions (128 irradiation and light receiving directions each)
59,240 for movement (number of faces as in previous example)
Multiplying both results in 970, 588, 160 calculations.
On the other hand, in the comparative example,
About direction, 24 × 12 × 24 → 69,120 (Yaw, Roll is 360 degrees, Pitch is 180 degrees divided by 15 degrees)
About movement, 150 × 150 × 150 → 3,375,000 (XYZ is divided into 1cm by 1cm)
Multiplying both results in 233,280,000,000 calculations.
When these are compared, the calculation amount is 237.3 times that of the present embodiment in the comparative example. In the demonstration experiment of the present embodiment, it takes approximately 3 hours for the calculation. Therefore, in the comparative example, it is assumed that approximately 711.9 hours (29.7 days) are required. Since several days or more are required only to determine the combination of measurement directions, the comparative example is not suitable for practical use.

  As described above, according to the work support system 2 in the present embodiment, in the three-dimensional measurement work, a combination of measurement positions at which work can be performed efficiently can be determined within a practical time.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  In the above embodiment, the combination of the measurement direction priority and the measurement direction is determined based on the area measurable from each measurement direction, but the measurement direction is determined based on the number of surfaces measurable from each measurement direction. A combination of priority and measurement direction may be determined.

2 ... Work support system 5 ... Measuring device 6 ... Moving device 10 ... Work support device 11 ... Work support program 100 ... Candidate position setting unit 102 ... Possible surface calculation unit 104 ... Impossible surface identification unit 106 ... Determination unit 108 ... Priority order Determination unit 110 ... condition changing unit 112 ... measurement control unit 120 ... specification information database 122 ... design information database

Claims (9)

A candidate position setting unit that sets candidate work positions for the entire work target range designated as the work target range among the surfaces of the work target;
For each work position set by the candidate position setting unit, a possible surface calculation unit that calculates the number or area of the surfaces of work objects that can be worked,
A work support apparatus comprising: a determination unit that determines a combination of work positions based on the number or area of surfaces calculated by the possible surface calculation unit. The work is a measurement work of 3D shape data,
The candidate position setting unit sets the measurement direction as at least the work position with respect to the entire circumference of the measurement target range of the measurement object,
The possible surface calculation unit calculates the number or area of surfaces capable of measuring a three-dimensional shape for each set measurement direction based on design information of a measurement object,
The work support apparatus according to claim 1, wherein the determination unit determines a combination of measurement directions based on the calculated number or area of surfaces. The candidate position setting unit sets only candidate measurement directions for the entire circumference of the measurement object,
The possible surface calculation unit calculates the number or area of surfaces that can be measured for each set measurement direction,
For each measurement direction, it further comprises a rank determining unit that determines the measurement priority according to the calculated number or area of the surface,
The work support apparatus according to claim 2, wherein the determination unit determines a combination of measurement directions based on the priority order determined by the order determination unit and an allowable number of measurements or measurement time. The candidate position setting unit sets only candidate measurement directions for the entire circumference of the measurement object,
The possible surface calculation unit calculates the number or area of surfaces that can be measured for each set measurement direction,
For each measurement direction, according to the calculated number or area of the surface, a rank determination unit that determines the measurement priority,
The work support apparatus according to claim 2, further comprising: a measurement control unit that instructs to perform measurement in each measurement direction according to the priority order determined by the order determination unit. An impossible surface specifying unit for specifying an impossible surface that cannot be measured from any measurement direction set by the candidate position setting unit based on the design information of the measurement object and the specification information of the three-dimensional shape measuring apparatus; In addition,
The possible surface calculation unit excludes the impossible surface specified by the impossible surface specifying unit from the surface in the measurement target range of the measurement object, and targets the surface of the measurement target range from which the impossible surface is excluded. The work support device according to claim 3, wherein the number or area of measurable surfaces is calculated for each measurement direction. A condition changing unit that replaces a part of the combination of the measurement directions provisionally determined by the determination unit with another measurement direction using a random number;
The work support apparatus according to claim 5, wherein the determination unit determines a combination of measurement directions to be employed by comparing the provisionally determined combination with the combination changed by the condition change unit. A measuring device for measuring the three-dimensional shape data of the measurement object;
A moving device that moves at least one of the measurement object and the measurement device to change a measurement position of the measurement object by the measurement device;
A work support device for controlling the mobile device,
The work support device includes:
A candidate position setting unit that sets candidate measurement positions for the entire measurement target range designated as the measurement target range among the surfaces of the measurement target;
For each measurement position set by the candidate position setting unit, possible surface calculation unit for calculating the number or area of the surface of the measurement object that can be measured,
For each measurement direction, according to the number or area of the surface calculated by the possible surface calculation unit, a rank determination unit that determines the priority of measurement,
A work support system comprising: a measurement control unit that instructs the mobile device to perform measurement in each measurement direction according to the priority order determined by the order determination unit. A candidate position setting step for setting candidate work positions for the entire work target range designated as the work target range among the surfaces of the work target;
For each work position set by the candidate position setting step, a possible surface calculation step for calculating the number or area of the surfaces of work objects that can be worked,
A determination step of determining a combination of operation positions based on the number or area of surfaces calculated by the possible surface calculation step. A candidate position setting step for setting candidate work positions for the entire work target range designated as the work target range among the surfaces of the work target;
For each work position set by the candidate position setting step, a possible surface calculation step for calculating the number or area of the surfaces of work objects that can be worked,
A program for causing a computer to execute a determination step of determining a combination of work positions based on the number or area of surfaces calculated by the possible surface calculation step.

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