JP6029282B2 - Workpiece assembly procedure calculation method, assembly procedure calculation program, part manufacturing method, and automatic assembly robot - Google Patents

Description

  The present invention relates to a multi-point fitting assembly in which a workpiece is assembled by inserting a plurality of fitting feet into corresponding fitting holes.

  In recent years, automatic assembly robots have attracted attention as production equipment that can handle production of a wide variety and a small quantity due to diversification of market needs. In general, an automatic assembly robot has a robot arm having a robot hand at the tip, and can be adapted to the assembly of various workpieces by changing the control program of the robot arm.

  Various automatic product assembly has been realized at the production site using the above-mentioned automatic assembly robot. For example, replacement by an automatic assembly robot such as multi-point fitting assembly is not easy, and many of them still rely on human hands. There is also an assembly.

  This multi-point fitting assembly is an assembly method in which a plurality of fitting feet are fitted into corresponding fitting holes, and a plurality of fitting feet are inserted into the fitting holes to be fitted to a fitting object. It is characterized by high binding force between objects. For this reason, it is often used for the assembly of exteriors with complicated shapes such as car air conditioners, but it automates the assembly that requires very high positioning accuracy for the robot arm when aligning the fitting feet and fitting holes. There was a problem with the above.

  Therefore, conventionally, by inserting soft fitting feet with relatively low rigidity during assembly into the fitting holes in order, the restraint generated between the inserted fitting feet and the fitting holes can be fitted with low rigidity. It has been devised to maintain a loose state using elastic deformation of the foot (see Patent Document 1).

Japanese Patent No. 2768210

  Thus, if the restraint between the workpieces to be assembled is held loosely, the robot arm can be operated without difficulty when the next fitting foot is inserted. However, depending on the shape of the workpiece, it may be difficult to insert into the fitting holes in order from the fitting feet with low rigidity.

  For example, as shown in FIG. 13 (a), when two fitting feet having different insertion lengths (lengths) are inserted into the fitting holes, the fitting feet having a short insertion length are inserted first because the rigidity is low. If an attempt is made to insert into a fitting foot, the fitting foot having a long insertion length may interfere with an object to be fitted and plastically deform.

SUMMARY OF THE INVENTION An object of the present invention is to provide a workpiece assembly procedure calculation method, an assembly procedure calculation program , a part manufacturing method, and an automatic assembly robot that determine the insertion order of fitting feet in consideration of the insertion length of the fitting feet. And

In the workpiece assembly procedure calculation method according to the present invention, the calculation device includes the first and second workpieces among the first and second workpieces that are assembled to each other by fitting the fitting feet into the corresponding fitting holes . For each of the plurality of fitting feet provided on at least one of the workpieces, a data acquisition step of acquiring insertion length data, which is a length inserted into the corresponding fitting hole, and the acquired fitting based on the data of the insertion length of the foot, e Bei a, an insertion sequence setting step of setting the order of insertion Hamagoashi to be inserted into the fitting hole in order from the long fitting-legged insertion length, the operation When there are a plurality of fitting feet having the same insertion length in the insertion sequence setting step, the apparatus can determine whether the fitting feet located at both ends are located on both ends if all of the fitting feet have the same insertion length. , Either one as the standard fitting foot and the other end from this standard fitting foot Setting the insert order to insert the fitting hole in order toward the fitting leg, characterized in that.
In the workpiece assembly procedure calculation method according to the present invention, the calculation device includes the first and second workpieces of the first and second workpieces that are assembled to each other by fitting the fitting feet into the corresponding fitting holes. For each of the plurality of fitting feet provided on at least one of the second workpieces, a data acquisition step of acquiring insertion length data that is a length inserted into the corresponding fitting hole, and the acquired fitting An insertion order setting step for setting the insertion order of the fitting legs so that the insertion legs are inserted in order from the fitting legs having a long insertion length based on the insertion length data of the joint legs, and the calculation When there are a plurality of fitting feet having the same insertion length in the insertion order setting step, the device is surrounded by the fitting feet having the same insertion length unless all of the fitting feet having the same insertion length are on the same straight line. A pair of mating feet that maximizes the area of the enclosed go area In the fitting, one of the fitting feet located at the apex portion is set as a reference fitting foot, and the fitting from the reference line drawn so as not to pass through the reference fitting foot and within the surrounding area is close. The insertion order is set so as to insert into the fitting hole in order from the foot.

An automatic assembly robot according to the present invention grips at least one of the first and second workpieces that are assembled to each other by fitting a plurality of fitting feet into corresponding fitting holes, and is a robot arm that is assembled to the other workpiece. If, e Bei and a computing device for setting the order of insertion Hamagoashi to insert a long fitting-legged insertion length into the fitting holes corresponding to the order, the arithmetic unit, fitting insertion length the same If there are multiple mating feet, if all of the mating feet with the same insertion length are on the same straight line, one of the mating feet located at both ends is set as the standard mating foot, and this standard mating foot is used. The insertion order is set so as to be inserted into the fitting hole in order from the foot toward the fitting foot on the other end side .
Further, the automatic assembly robot according to the present invention grips at least one of the first and second workpieces that are assembled to each other by fitting the corresponding fitting holes into the corresponding fitting holes, and assembling the other workpiece. A robot arm, and an arithmetic device that sets the insertion order of the fitting feet so that the insertion feet are inserted into the corresponding fitting holes in order from the fitting feet having a long insertion length, and the arithmetic devices have the same insertion length When there are a plurality of fitting feet, if all of the fitting feet having the same insertion length are not on the same straight line, the fitting foot having the maximum area of the surrounding area surrounded by the fitting feet having the same insertion length is used. In the combination, one of the fitting feet located at the apex portion is used as a reference fitting foot, and the fitting is close to the reference line drawn so as not to pass through the reference fitting foot and within the surrounding area. Insert the insertion order so that it is inserted into the fitting hole in order from the foot. A constant, characterized in that.

  According to the present invention, in order to determine the insertion order of the mating feet in order from the mating foot having the long insertion length, even if there are a plurality of mating feet having different lengths, the mating feet that are easy to contact the workpiece are sequentially The fitting foot can be inserted into the fitting hole, and the accuracy of multi-point fitting assembly can be improved.

The schematic diagram which shows the automatic assembly system of the workpiece | work which concerns on embodiment of this invention. The schematic diagram which shows the control apparatus of the automatic assembly robot which concerns on embodiment of this invention. The flowchart figure which shows the assembly procedure of the multipoint fitting assembly which concerns on embodiment of this invention. The flowchart figure which shows the determination method of the insertion order of the fitting leg in the procedure of the multipoint fitting assembly of FIG. The flowchart figure which shows the determination method of the insertion order of the fitting leg of the same insertion length. The flowchart figure which shows the determination method of a reference | standard fitting leg. The schematic diagram which shows the determination procedure of the reference | standard fitting leg in a triangular shaped workpiece | work. The schematic diagram which shows the determination procedure of the reference | standard fitting leg in the star-shaped workpiece. (A) The schematic diagram which shows how to obtain | require a reference line, (b) The schematic diagram which shows the case where a fitting leg is classified according to the distance from a reference line. The flowchart figure which shows the setting procedure of the insertion order of a fitting leg in case there exist two or more fitting legs with the same distance from a reference line. It is a schematic diagram which shows an example of the workpiece | work concerning embodiment of this invention, Comprising: (a) The perspective view, (b) The perspective view which shows the 1st workpiece | work. (A) The schematic diagram which shows the dimensional relationship of the 1st workpiece | work of FIG. 11, (b) The schematic diagram which shows the dimensional relationship of the 2nd workpiece | work of FIG. (A) The figure which shows the form of the assembly defect of a fitting leg in case the insertion length of a fitting leg differs, (b) The figure which shows the case where the assembly defect resulting from arrangement | positioning of a fitting leg occurs, (c) End part The figure which shows the case where the assembly defect of the fitting leg | foot of this occurs.

[Configuration of automatic assembly system]
Hereinafter, a multipoint fitting assembly according to an embodiment of the present invention will be described with reference to the drawings. In the following description, the insertion length of the fitting foot f corresponds to the time when the first work W1 (fitting object) and the second work W2 (fitting object) are fitted and assembled. It means the length that the fitting foot f enters the fitting hole h.

  As shown in FIG. 1, the automatic assembly system S for workpieces W includes first and second workpieces W1, which are fitted to each other by fitting a plurality of fitting feet f... Into corresponding fitting holes h. This is an automatic assembly system for assembling W2. This automatic assembly system S assembles the fitting supply device 21 that supplies the first workpiece W1, the fitting supply device 23 that supplies the second workpiece W2, and the first and second workpieces W1 and W2. And an automatic assembly robot 1.

  The automatic assembly robot 1 has a robot arm 2 mounted on an assembly base 20, and a mating object mounting table 22 on which a second workpiece W2 is mounted is provided on the assembly base 20. ing. Further, the fitting supply device 21 is disposed between the attachment base of the robot arm 2 and the fitting object mounting table 22 on the assembly base 20. Furthermore, a to-be-fitted material supply device 23 is provided on the opposite side of the to-be-fitted material mounting table 22 with respect to the fitting material supply device 21.

  The automatic assembly system S uses the robot arm 2 to place the second workpiece W2 on the workpiece mounting table 22, and then grips the first workpiece W1 from the fitting supply device 21. The workpiece W1 is automatically assembled to the second workpiece W2 on the fitting object mounting table.

[Configuration of automatic assembly robot]
Next, the configuration of the automatic assembly robot 1 described above will be described in detail with reference to FIGS. The automatic assembly robot 1 includes the robot arm 2, an imaging device 6 that images the first and second workpieces W1 and W2, and a robot controller (computer, control device) 10 that controls these devices 2 and 6. ing.

  The robot arm 2 includes an arm portion 2a formed of a vertical articulated robot, and a robot hand 3 attached to a movable end 2b of the arm portion 2a via a force sensor 5. Then, the reaction force applied to the robot hand 3 is detected by the force sensor 5, and the detected reaction force is fed back to the command value for position control or torque control of the arm portion 2a. A delicate assembly is possible.

  As shown in FIG. 2, the robot controller 10 is configured by connecting the robot arm 2 and the imaging device 6 to a computer main body having a calculation device 102 and a storage device 103. Further, a teaching pendant 116, an input device 106, a display device 107, and the like for an operator to perform input work are also connected to the computer main body.

  In the storage device 103, the shape data of the first and second workpieces W1, W2 (insertion length l (dimension) of the fitting foot f (fitting hole h) and positional relationship), physical property data, fitting feet Data such as strength data (rigidity and allowable deformation amount) of f is stored. In addition, a control driver such as the robot arm 2 and the imaging device 6, an assembly procedure calculation program CPR for causing the computer (calculation device 102) to calculate a workpiece assembly procedure based on the shape of the fitting foot f, etc. The various programs are stored.

  More specifically, the computer main body includes the CPU 102a as a main body, and includes the image processing device 102b and the sound processing device 102c to constitute the arithmetic device 102. In addition to the image processing device 102b and the sound processing device 102c, a ROM 103a and a RAM 103b are connected to the CPU 102a via a bus 111. The ROM 103a stores programs necessary for basic control of the robot and various programs and data such as the assembly procedure calculation program CPR described above. A working area for the CPU 102a is secured in the RAM 103b. The image processing apparatus 102b controls a display as the display apparatus 107 in accordance with a drawing instruction from the CPU 102a to display a predetermined image on the screen. The sound processing device 102c generates a sound signal corresponding to the sound generation instruction from the CPU 102a and outputs the sound signal to the speaker 109.

  The bus 111 is connected to the robot arm 2 and the imaging device 6, and is also connected to a recording disk reader 115. The bus 111 reads a recording medium D on which an assembly procedure calculation program CPR and the like are recorded. It can be stored. The storage device 103 described above includes a computer-readable recording medium D and other external storage devices in addition to the ROM 103a and the RAM 103b which are main storage devices.

  Further, a communication device 112 is connected to the bus 111. Accordingly, the assembly procedure calculation program CPR distributed from the Internet or the like via the communication device 112 can be downloaded without using the recording medium D as described above.

[Outline of assembly procedure]
Next, the multi-point fitting assembly procedure of the workpiece based on the assembly procedure calculation program CPR will be described.

FIG. 3 is a flowchart showing an assembling procedure by the automatic assembling robot 1. The assembling is roughly divided into an _off- line procedure calculation (trajectory generation) S _off and an on-line control S _on of the robot arm 2.

In the off-line (S _off ) trajectory generation, the insertion order of a plurality of fitting feet f is first determined (step S1 in FIG. 3). Next, an assembly flow for inserting the fitting feet f into the corresponding fitting holes h in the order determined in step S1 is created (S2). Finally, an insertion trajectory for each insertion order is determined (S3). The assembly flow refers to the movements performed by the automatic assembly robot 1 until the fitting feet f are sequentially inserted into the fitting holes h and finally the fitting is completed. It is a thing. Here, the unit of operation is, for example, automatic assembly such as moving the first work W1 to a predetermined position with respect to the second work W2, moving the first work W1 until contact, or controlling a track for inserting the fitting foot f. This is the movement that the robot 1 performs during assembly.

Next, control of the automatic assembly robot performed online (S _on ) will be described. In the online control, the robot arm 2 is operated according to the trajectory determined offline (S4). Then, during assembly in which contact between the first and second workpieces W1 and W2 occurs, a reaction force applied to the robot hand 3 is detected so that an excessive load is not applied to the first workpiece W1 and the second workpiece W2. Further, fine adjustment of the position of the first workpiece W1 is performed by the robot arm 2 (S5). Online control is constituted by these two procedures.

  Although not shown in FIG. 3, when an abnormal reaction force is detected during assembly, a retry operation may be performed by estimating the assembly state. If an abnormal reaction force is detected in the force sensor 5 during online control, retry or assembly stop, fitting or fitting is performed based on the threshold or reaction force profile set by the user handling the automatic assembly robot 1. Judgment such as replacement of compound parts.

[Calculation method of mating foot insertion order]
Next, in the assembly procedure described above, the calculation method of the insertion order of the fitting feet f (S1, the insertion order determination step) will be described with reference to FIGS. As shown in FIG. 4, in determining the insertion order of the fitting feet f (step S10 in FIG. 4), the arithmetic unit 102 first inserts the insertion length for each of the plurality of fitting feet f formed on the workpiece. l and intensity data are read out from the storage unit 103 and acquired (S11, data acquisition step).

  Next, the computing device 102 classifies the plurality of fitting feet f for each insertion length based on the acquired shape data of the fitting feet f (S12, classification step). And the insertion order of the fitting leg contained in a processing unit is set in order from the group (processing unit) of the long fitting leg of insertion length l (No of S13-S15, insertion order setting process). Then, by setting the insertion order for the fitting feet f of all the processing units (Yes in S15), the setting of the insertion order of the fitting feet f is completed (S16).

[Insertion order of mating feet within each processing unit]
By the way, since the insertion lengths l of the fitting feet f grouped into the same group in step S12 are the same, the insertion order is determined based on their arrangement and strength. Specifically, as shown in FIG. 5, first, the arithmetic unit 102 determines how many fitting feet f are included in the processing unit (steps S21 and S25 in FIG. 5).

  At this time, when the number of the fitting feet f is one (Yes in S21), the arithmetic unit 102 inserts the fitting feet f into the fitting holes h first in the group. f is determined (S22-24). On the other hand, when the number of fitting feet f is two (No in S21, Yes in S25), the fitting feet f are inserted from relatively low strength fitting feet f out of these two fitting feet f. The insertion order of the fitting feet f is determined (S26). It is to be noted that the reason why the robot arm is inserted from the low-strength fitting foot f is that when the next fitting foot f is inserted, the restraint between the first and second workpieces by the inserted fitting foot f is weak. This is because the position adjustment between the first workpiece W1 and the second workpiece W2 can be easily performed in step 2.

  Also, when the number of fitting feet in the processing unit is three or more (No in S21, No in S25), unlike the case of the one and two, the fitting is focused on the positional relationship of the fitting feet f. The insertion order of the leg f is determined. When determining that there are three or more fitting feet f, the arithmetic unit 102 first determines whether or not the fitting feet f are aligned on the same straight line (S27). Here, when the fitting feet f are aligned on the same straight line (Yes in S27), the fitting feet f at the center may be damaged during the assembly in the form as shown in FIG. 13B. . Therefore, among the fitting feet f located at both ends, the fitting foot having the relatively low strength is used as the fitting foot (first reference fitting foot) to be inserted first in the group (S28). . Thereafter, the insertion order is determined so that the fitting feet are inserted toward the fitting feet at the opposite end in order from the fitting feet close to the first inserted fitting feet (S29, S30, S24).

  On the other hand, when the fitting feet f are not aligned on the same straight line (No in S27), the arithmetic unit 102 selects one of the fitting feet in the processing unit as a reference fitting foot (second reference fitting foot) fc. (For example, the fitting foot f1 in FIG. 9) (S31). Then, the reference fitting foot fc is set as a fitting foot to be inserted first (S32).

  As shown in FIG. 6, the reference fitting foot fc is obtained by first finding a combination of the fitting feet f in which the area of the region formed by connecting the XY coordinates of the fitting feet f included in the processing unit is maximized. (Step S41 in FIG. 6). In the region (enclosed region) R surrounded by the fitting foot f that forms this maximum combination, the fitting foot having the lowest strength among the fitting feet located at the apex portion is the reference fitting foot. It is set (S42-44).

  For example, in the case of the triangular workpiece shown in FIG. 7, a portion surrounded by a dotted line in FIG. 7B is a region R formed by connecting the fitting feet f1 to f7, and all the regions surrounded by the dotted line are included. The computing device 102 calculates the area for the region. Then, when the maximum area among the calculated areas is obtained, it is as shown in FIG. 7C, and the combinations of the fitting feet at that time are f1, f2, f3, f4, f6, and f7. Of these fitting feet, any one of the fitting feet f1, f3, f7 located at the apex, more preferably the fitting foot having the lowest strength is used as the reference fitting foot. Selected.

  Similarly, even in a star-shaped workpiece as shown in FIG. 8, a portion surrounded by a dotted line in FIG. 8B is a region R formed by connecting the fitting feet f1 to f10. The combination of fitting feet that maximizes the area is as shown in FIG. This special, the fitting foot located at the apex is f1, f3, f5, f7, f10, and any one of these fitting feet f1, f3, f5, f7, f10 is more preferable. The fitting foot having the lowest strength is selected as the reference fitting foot.

  When setting the reference fitting foot fc, the plane coordinates that determine the position of the fitting foot f are set so that the fitting foot f is fitted when the first workpiece W1 is fitted to the second workpiece W2. It is preferable to set a plane coordinate orthogonal to the insertion direction to be inserted into the hole h.

  When the reference fitting foot fc is selected (step S32 in FIG. 5), the arithmetic unit 102 draws a reference line L that passes through the reference fitting foot fc (S33). The reference line L is drawn so as not to intersect with the surrounding region R surrounded by the combination of the fitting feet having the maximum area. For example, the workpiece in FIG. 9 in which the fitting foot f1 becomes the reference fitting foot fc is taken as an example. In other words, the range of the angle α is a range in which the reference line L can be drawn.

  When the reference line L is drawn, the arithmetic unit 102 classifies the fitting feet included in the processing unit for each distance from the reference line L (step S34 in FIG. 5). Then, a group (processing unit) D1 having a short (close) distance from the reference line L is selected (S35), and the insertion order is sequentially determined for the fitting feet included in the processing unit of the selected distance ( S36). Thereby, the insertion order is determined for all the fitting feet f in the processing unit L (S37, S24).

  As shown in FIG. 9B, in the fitting feet grouped according to the distance from the reference line L, the fitting feet (for example, f1, f2, f3 and f4, f5) having the same distance from the reference line L. , F6) in some cases.

  Therefore, as shown in FIG. 10, for the fitting feet f grouped by the distance from the reference line L, it is first determined whether or not the number of fitting feet included in the distance processing unit D is one. (Step S51 in FIG. 10). If there is one (YES in S51), the fitting foot f is selected as the next fitting foot to be inserted (S52), and the determination of the insertion order of the fitting feet included in this distance processing unit is completed. (S53, S54).

  On the other hand, when the number of fitting feet included in the processing unit is not one (NO in S51), it is determined whether or not the number of fitting feet included in the processing unit is two (S55). If there are two (YES in S55), the insertion order is selected from the two soft fitting feet having relatively low rigidity (S56). When the number of fitting feet included in the distance processing unit is three or more (NO in S55), fitting with relatively low rigidity among the fitting feet f located at both ends aligned on the same straight line The insertion order is determined so as to select and insert from the foot f in order from the end (S57 to S59). Since the fitting feet included in the distance processing unit have the same distance from the reference line, they are necessarily aligned on the same straight line.

  For example, when the reference line L is drawn as shown in FIG. 9B, the fitting feet f1 to f7 are the group D1 of the fitting feet f1, f2, and f3 and the group D2 of the fitting feet f4, f5, and f6. And a group D3 of fitting feet f7. Of these fitting feet f1-7, the insertion order is determined from the group of fitting feet f1, f2, f3 closest to the reference line L, and either one of the fitting feet f1, f3 at both ends. The order is set from the fitting foot to the other fitting foot. When there are fitting feet f2 and f3 having the same distance from the reference line L and the fitting foot f1 which is the reference fitting foot fc, the strength of the fitting feet at the other end is lower than that of the reference fitting foot. The insertion order may be set from the fitting foot f3 on the other end side toward the reference fitting foot f1.

  When the insertion order of the fitting feet f1, f2, and f3 is determined, the insertion order of the fitting feet f4, f5, and f6 is then set in the same manner as the fitting feet f1, f2, and f3 groups. It is determined.

  Thus, when there are three or more fitting feet in the processing unit and they are not arranged on the same straight line, the distance from the reference line L passing through the reference fitting feet (second reference fitting feet) fc is short ( Explain why the order of insertion must be selected from the (close) mating foot.

  If the insertion order is selected from the fitting foot that is short (near) from the reference fitting foot (second reference fitting foot) without drawing the reference line L, the fitting foot breaks during assembly in the following manner There are things to do. For example, assuming that the lowest fitting foot among the fitting feet f1, f3, and f7 located at the apex in the workpiece of FIG. 9 is f7, the fitting foot f7 is selected as the reference fitting foot. At this time, when the insertion order is selected not from the reference line L passing through the fitting foot f7 but from a fitting foot having a short distance from the fitting foot f7, the fitting foot selected next to the fitting foot f7. Becomes f5. However, since the fitting feet f4, f5, and f6 are on the same straight line, unless the fitting feet f4 and f6 located at both ends are selected in order, the end as shown in the example of FIG. There is a risk that the fitting feet f4 and f6 in the middle are damaged during the assembly. In order to avoid such an insertion order, it is necessary to select the insertion order from the fitting feet that are short (close) from the reference line L passing through the reference fitting feet fc.

  Further, when the reference line L passing through the reference fitting foot fc is drawn next (S33), the reference line L must be drawn so as not to intersect with the surrounding region R surrounded by the combination fitting foot having the largest area. Explain why this is necessary.

  For example, suppose that the reference line L is drawn so as to pass through the reference fitting foot (second reference fitting foot) fc and the fitting foot f5 in the workpiece of FIG. At this time, the reference line L is in a state of intersecting with the surrounding region R surrounded by the fitting feet f1 to f4, f6, and f7 of the combination having the largest area. When the insertion order is selected from the fitting feet that are short (near) from the reference line L, the fitting feet fc are selected first, and then the fitting feet f5 are selected. However, in this case as well, since the fitting feet f4, f5, and f6 are on the same straight line, unless the fitting feet f4 and f6 located at both ends are selected in order, the example of FIG. Thus, there is a risk that the fitting feet f4 and f6 at the ends are damaged during the assembly. In order to avoid such an insertion order, the reference line L passing through fc intersects with the surrounding area R surrounded by the fitting feet f1 to f4, f6, and f7 of the combination having the largest area. It is necessary to pull so as not to.

  In the example of FIG. 9, it is not uniquely determined where the reference line L should be drawn within the range of the angle α that is a range in which the reference line L can be drawn. However, by drawing the reference line L at least in this range and selecting the order in accordance with the calculation method of the insertion order described so far, the fitting foot f is damaged during the assembly in the form as shown in FIG. You can avoid that.

  Next, the case where the insertion order of the fitting feet of the workpiece shown in FIGS. 11 and 12 is set using the assembly procedure described above will be described. As shown in FIG. 11, the workpiece W includes a first workpiece W1 as a fitting having a plurality of fitting feet f1 to f9 and a plurality of fittings into which the plurality of fitting feet f1 to f9 are inserted. It is comprised by the 2nd workpiece | work as a to-be-fitted object which has the leg | foots h1-9. Further, as shown in FIG. 12, the dimensional relationship between the first and second workpieces is as follows: a1 = a2 = b1 = b2 = 40 mm, a3 = a4 = b3 = b4 = 25 mm, a5 = a6 = b5 = b6 = 10 mm A7 = b7 = 40 mm and a8 = a9 = b8 = b9 = 25 mm. Furthermore, the diameter of the fitting foot f is 2 mm, and the diameter of the fitting hole is 2.1 mm.

  Further, the relationship between the insertion length l and the rigidity k of each of the fitting feet f to f9 is as shown in the following table.

  In determining the insertion order, the arithmetic unit 102 first sets the fitting feet f1 to f9 according to the insertion length l to a first processing unit L1 having an insertion length l of 15 mm and a second process having an insertion length of 5 mm. Classify into unit L2.

  Next, the arithmetic unit 102 has a combination of the fitting feet f1, f2, f3, f4, f6, and f7 having the largest internal area with respect to the fitting feet f1 to f7 of the first processing unit L1 having a longer insertion length. Of the f1, f3, and f7 serving as the apex portions, f1 having the lowest rigidity is set as the reference fitting foot fc. Then, a reference line L is drawn so as to pass through the reference fitting foot f1 and overlap the side where the fitting feet f1, f2, and f3 exist. Accordingly, the first group D1 (fitting feet f1 to f3), the second group D2 (fitting feet f4 to f6), the third group D1 (fitting feet f1 to f3) according to the distance from the reference line. The fitting feet are classified into three groups of group D3 (fitting feet f7).

  When the fitting feet are classified in this way, the insertion order starts to be set from the first group D1 having the shortest distance from the reference line L (d = 0, see FIG. 9). The arithmetic unit 102 sets the fitting foot f1 of the first group D1 as the fitting foot to be inserted first because the fitting foot f1 is the reference fitting foot fc. Then, the insertion order is set so that the fitting feet of the first group D1 are inserted from the fitting feet f1 toward the fitting feet f3 on the other end side in the order of the fitting feet f1, f2, and f3.

  When the insertion order of the fitting feet of the first group D1 is determined, the arithmetic unit 102 next selects the fitting feet f4 to f6 of the second group D2 (d1 = 40 mm) next to the reference line L next to the first group D1. Set the insertion order for. Here, among the fitting feet f4 and f6 at both ends of the second group D2, the fitting foot f4 has lower rigidity, so that the fitting foot of the second group D2 is f4 toward f6 from f4, The insertion order is set so as to be inserted following the fitting feet of the first group in the order of f5 and f6.

  Then, the computing device 102 finally sets the insertion order of the fitting feet f7 included in the third group D3 (d2 = 90 mm) next to the fitting feet f6 of the second group D2, and the first processing unit L1. The setting of the insertion order of the fitting feet f1 to f7 is completed.

  When the setting of the insertion order of the fitting feet f1 to f7 of the first processing unit L1 is completed, the arithmetic unit 102 determines whether there is an undecided insertion order for the processing unit L of the insertion length l. The insertion order is determined for the fitting feet f8 and f9 of the second processing unit L2. Here, since the second processing unit L2 includes two fitting feet f8 and f9, the fitting feet f8 to the fitting feet having relatively low rigidity among these two fitting feet. Is inserted in the order of the fitting feet f8 and f9.

  When the setting of the insertion order of the fitting feet f8 and f9 of the second processing unit L2 is completed, the arithmetic unit 102 confirms whether there is an insertion length yet to be determined for the processing unit of the insertion length. The calculation of the insertion order of the gait ends. Accordingly, the insertion order of the fitting feet f1 to f9 of the first workpiece in FIGS. 11 and 12 is the order of f1, f2, f3, f4, f5, f6, f7, f8, and f9.

[Summary]
In this way, in the multi-point fitting assembly, by setting the insertion order of the fitting legs so that the fitting legs f are inserted in order from the fitting legs f having the long insertion length l, FIG. It is possible to prevent the fitting foot having a long length as shown in FIG. That is, the assembly problem due to the difference in the length of the fitting foot f can be solved by determining the insertion order in the order of arrival at the work of the other party.

  Further, when there are a plurality of fitting feet f having the same insertion length l, the insertion order is set so that the insertion feet are inserted in order from the fitting feet close to the already inserted fitting feet f. The problem caused by the placement problem can be solved. More specifically, when the fitting feet f having the same insertion length l are on the same straight line, the fitting feet at either one of the two end portions are used as reference fitting feet (first reference fitting feet). And the insertion order of the fitting feet f is set in order from the reference fitting feet toward the fitting feet f at the other end. Thereby, it can prevent that the fitting leg f of a center part is damaged like FIG.13 (b).

  Furthermore, even if all of the fitting feet f having the same insertion length are not on the same straight line, one fitting foot located at the apex portion among the plurality of fitting feet is used as a reference fitting. The foot (second reference fitting foot) fc. Then, the reference line L is drawn so as not to pass through the reference fitting foot fc and within the surrounding area surrounded by the fitting foot f, and the fitting feet f that are close to the reference line L are inserted in order from the fitting foot f. The insertion order of the fitting feet f is set in (1). Thereby, it can prevent that the fitting leg f of an edge part is damaged like FIG.13 (c).

  Further, by introducing the concept of the reference line L, the fitting feet f having the same distance from the reference line L are always located on the same straight line. Therefore, in such a case, as described above, in order to avoid collision of the fitting foot f at the center with the counterpart work, the direction from one fitting foot f at both ends to the other fitting foot f is avoided. The insertion order may be set in order. In other words, when there are a plurality of fitting feet f on the parallel line of the reference line L, one of the fitting feet located on both ends of the fitting feet f on the parallel line is used as a reference. A fitting foot (third reference fitting foot) is used. Then, the insertion order may be set so that the insertion holes are sequentially inserted from the reference fitting foot toward the fitting foot on the other end side.

  Furthermore, when the insertion order of the fitting foot cannot be distinguished even by the insertion length l or the arrangement of the fitting foot f described above, the inserted fitting is inserted by inserting from the fitting foot f having a relatively low strength. The restraint between the first and second workpieces by the foot can be kept loose. In the present embodiment, the strength data for each of the plurality of fitting feet is acquired in the data acquisition step, and when the first to third reference fitting feet are selected, the fitting feet having the lowest possible strength are selected. doing.

  That is, in the case of the first reference fitting foot which is a reference fitting foot when all the fitting feet having the same insertion length are on the same straight line, the lower strength of the fitting feet located at both ends A mating foot is selected. Further, in the combination of the fitting feet f in which the area of the surrounding region R surrounded by the fitting feet having the same insertion length is maximized, the second reference fitting foot which is one of the fitting feet located at the apex portion. In this case, the fitting foot having the lowest strength is selected from the fitting feet positioned at the apex portion. Further, in the case of the third reference fitting foot which is one of the fitting feet located on both ends of the fitting feet on the parallel line of the reference line, the fitting located on both ends. Of the legs, the fitting leg with the lower strength is selected.

  In addition, if an allowable deformation amount, which is a deformation amount that allows the fitting foot to be deformed within the elastic range, is used as an index for evaluating the strength of the fitting foot, the fitting foot can be more accurately evaluated than a simple rigidity value. Damage can be prevented. In particular, when the allowable deformation amount obtained in at least the horizontal direction in which the workpiece is moved is used for each fitting foot, damage to the fitting foot can be prevented with higher accuracy. On the other hand, when the rigidity value of the fitting foot is used for strength evaluation, data can be easily obtained.

  Furthermore, in this embodiment, when there are a plurality of rows of fitting foot processing units on the parallel line from the reference line L, the end on the side closer to the fitting foot inserted last in the previous group. The insertion order may be determined from the fitting foot of the part toward the fitting foot on the other end side. For example, in the case of the workpiece of FIG. 9, the fitting feet f4, f5, and f6 may be inserted in the order of f4, f5, and f6. When the insertion order of the groups of the fitting feet f4, f5, and f6 is determined, the insertion order of the fitting feet f7 is set as the last fitting foot to be inserted, and the insertion order of the fitting feet f1 to f7 is set. May be terminated.

  Further, two or more fitting feet f having the same insertion length l are inserted simultaneously only when the dimensional tolerance between the fitting feet f and the fitting holes h is sufficiently large with respect to the positioning accuracy of the robot arm 2. You may choose. Inserting them at the same time can reduce the assembly time. On the other hand, as the number of fitting feet f to be inserted simultaneously increases, the requirement for positioning accuracy of the robot arm 2 becomes higher than in the case of sequential insertion, and therefore there is a higher risk that the fitting feet f will interfere with the workpiece W. Become. For this reason, it is preferable to select according to the purpose of emphasizing tact or reliability.

  Further, in the present embodiment, a combination of the fitting feet f that maximizes the area of the surrounding region R is obtained, and any one of the fitting feet at the apex portion of the combination of the fitting feet is used as a reference fitting. It was a foot. However, one of the fitting feet at the apex can be defined as a fitting foot located further from an arbitrary reference point, and the surrounding region R is not necessarily used to set the reference fitting foot fc. It is not necessary to obtain a combination of the fitting feet f that maximizes the area of. That is, the fitting foot selected as a result is a combination of the fitting feet f in which the area of the surrounding region R is maximized. It may be the same fitting foot as any one of.

  In this embodiment, the columnar fitting foot f made of resin is employed, but any shape and material such as a peg-shaped fitting foot made of stainless steel may be used. Further, the fitting foot and the fitting hole do not necessarily need to exist separately on the work on one side and the other side, and may naturally exist together on the same work.

  Further, the insertion order of the fitting feet may be determined immediately before the insertion of the online fitting feet, not when offline, and is calculated by a computer configured separately from the automatic assembly robot. The communication may be communicated to the automatic assembly robot via a communication device.

102: arithmetic unit, f: fitting foot, h: fitting hole, l: insertion length, W1: first workpiece, W2: second workpiece, S11: data acquisition step, S12-15: insertion order setting step

Claims (10)

The plurality of fittings provided on at least one of the first and second workpieces among the first and second workpieces that are assembled to each other by fitting the fitting feet into the corresponding fitting holes. For each leg, a data acquisition step for acquiring insertion length data that is the length inserted into the corresponding fitting hole;
An insertion order setting step for setting the insertion order of the fitting feet so that the fitting feet are inserted in order from the fitting feet having a long insertion length based on the acquired insertion length data of the fitting feet. Bei example,
When there are a plurality of fitting feet having the same insertion length in the insertion order setting step, the arithmetic unit is provided with fitting feet positioned at both ends if all of the fitting feet having the same insertion length are on the same straight line. Among them, one of them is set as a reference fitting foot, and the insertion order is set so that the reference fitting foot is inserted into the fitting hole in order toward the fitting foot on the other end side.
A workpiece assembly procedure calculation method characterized by the above. The computing device, if the insertion length in the inserted sequence setting step is a plurality of identical Hamagoashi, unless prior Symbol insertion length all collinear same Hamagoashi same fitting of insertion length in combination Hamagoashi the area encircling a region surrounded by the leg is maximized, one of Hamagoashi located apex portion and the base semi-connected Goashi, and passes this criteria fits Goashi the Set the insertion order to insert into the fitting hole in order from the fitting foot that is close to the reference line drawn so as not to pass through the surrounding area,
The work assembly procedure calculation method according to claim 1. In the insertion order setting step, the arithmetic unit is not on all the fitting feet having the same insertion length on the same straight line, and if there are a plurality of fitting feet on the parallel line of the reference line, the computing devices are on the parallel lines. of Hamagoashi, and one of the fitting referenced to Hamagoashi Goashi of Hamagoashi located at both ends, in order toward the mating legs of the other end side from this criteria fits Goashi Set the insertion order to insert into the mating hole,
The workpiece assembly procedure calculation method according to claim 2. The computing device acquires strength data for each of the plurality of fitting feet in the data acquisition step,
The reference fitting foot selected when all the fitting feet having the same insertion length are on the same straight line is selected from the fitting feet having lower strengths among the fitting feet located at both ends. The reference fitting foot selected from the fitting feet positioned at the apex portion when not all of the fitting feet having the same insertion length are on the same straight line , When the lowest strength fitting foot is selected and there are a plurality of fitting feet on the parallel line of the reference line, the reference fitting foot selected is the strength of the fitting feet located at both ends. The lower mating foot is selected,
The work assembly procedure calculating method according to claim 3. The strength data is the rigidity of the fitting foot or the allowable deformation amount.
The work assembly procedure calculation method according to claim 4.   The plurality of fittings provided on at least one of the first and second workpieces among the first and second workpieces that are assembled to each other by fitting the fitting feet into the corresponding fitting holes. For each leg, a data acquisition step for acquiring insertion length data that is the length inserted into the corresponding fitting hole;
  An insertion order setting step for setting the insertion order of the fitting feet so that the fitting feet are inserted in order from the fitting feet having a long insertion length based on the acquired insertion length data of the fitting feet. Prepared,
  When there are a plurality of fitting feet having the same insertion length in the insertion order setting step, the arithmetic unit is configured so that all of the fitting feet having the same insertion length are not on the same straight line. In the combination of the mating feet that maximizes the area of the surrounding area surrounded by, one of the mating feet located at the apex portion is used as a reference fitting foot, and passes through the reference fitting foot and within the surrounding region. Set the insertion order to insert into the fitting hole in order from the fitting foot that is close to the reference line drawn so as not to pass through,
  A workpiece assembly procedure calculation method characterized by the above.   7. A component manufacturing method for manufacturing a component by assembling the first and second workpieces by an automatic assembly robot according to an assembly procedure calculated by the workpiece assembly procedure calculating method according to claim 1. An assembly procedure computation program for causing a computer to execute the workpiece assembly procedure computation method according to any one of claims 1 to 6 . A robot arm that grips at least one of the first and second workpieces that are assembled to each other by fitting the corresponding fitting holes into the corresponding fitting holes, and is assembled to the other workpiece;
E Bei and a computing device for setting the order of insertion Hamagoashi to be inserted into the fitting holes corresponding to the order from the long fitting-legged insertion length,
When there are a plurality of fitting feet having the same insertion length, the arithmetic unit determines either one of the fitting feet located at both ends if all of the fitting feet having the same insertion length are on the same straight line. Set the insertion order so that the reference fitting foot is inserted into the fitting hole in order from the reference fitting foot toward the fitting foot on the other end side,
An automatic assembly robot characterized by that.   A robot arm that grips at least one of the first and second workpieces that are assembled to each other by fitting the corresponding fitting holes into the corresponding fitting holes, and is assembled to the other workpiece;
  An arithmetic device that sets the insertion order of the fitting feet so as to insert into the fitting holes corresponding in order from the fitting feet having a long insertion length, and
  In the case where there are a plurality of fitting feet having the same insertion length, the arithmetic unit is configured so that the surrounding region surrounded by the fitting feet having the same insertion length is not all of the fitting feet having the same insertion length. In the combination of the mating feet with the maximum area, one of the mating feet located at the apex portion is used as a standard mating foot, and the mating foot is drawn so as not to pass through the standard mating foot and within the surrounding area. Set the insertion order to insert into the fitting hole in order from the fitting foot that is close to the reference line,
  An automatic assembly robot characterized by that.

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