JP2015066667A - Assembly device and control method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to handle various soft objects with a robot in plural work processes of an assembly device and its control method.SOLUTION: An assembly device includes: a stage 4 which can adjust the posture of a workpiece W; a robot 5 provided with a holding part 6 which holds a soft object S; a normal direction calculation part 23 which calculates a first normal direction n1 of the soft object S; a posture calculation part 25 which calculates a change amount of the posture of the workpiece W needed for coinciding a second normal direction n2 of the workpiece W with the first normal direction n1; a stage control part 29 which changes the posture of the workpiece W by the change amount by controlling the stage 4; and a robot control part 30 which assembles the soft object S to the workpiece W by controlling the robot 5 after the posture of the workpiece W is changed by the change amount.

Description

  The present invention relates to an assembling apparatus and a control method thereof.

  Electronic devices such as smartphones are manufactured by assembling various components. The parts include flexible objects such as cables and adhesive sheets, but the physical characteristics of the flexible objects vary from part to part, and the contents of assembly work are diverse. Therefore, it is difficult to handle all flexible objects with robots in all operations.

  If a robot is used, it is conceivable to suck the flexible object with a dedicated tool for handling a specific flexible object in a specific work process. However, since the tool is specialized for a dedicated work process, if the tool is used in another work process, the tool and the electronic device may interfere with each other and workability may be deteriorated.

  In addition, in this method, since a tool must be prepared for each work process and each part, it takes time to design the tool.

JP-A-8-174457 JP-A-2005-306187

  An object of the assembly apparatus and its control method is to allow a robot to handle various flexible objects in a plurality of work processes.

  According to an aspect of the disclosure below, a stage that can adjust the posture of a workpiece, a robot that includes a gripping unit that grips a flexible object, and a normal direction calculation that calculates a first normal direction of the flexible object A posture calculating unit that calculates a change amount of the posture of the workpiece required for the second normal direction of the workpiece to coincide with the first normal direction, and the stage. A stage control unit that changes the posture of the work by the change amount, and a robot control that assembles the flexible object to the work by controlling the robot after the posture of the work is changed by the change amount. An assembly apparatus having a portion is provided.

  According to another aspect of the disclosure, the process of calculating the first normal direction of the flexible object gripped by the gripping portion of the robot and the second normal direction of the workpiece held on the stage are A process for calculating a change amount of the posture of the work required to match one normal direction, a process for changing the posture of the work by the change amount by controlling the stage, After the posture is changed by the change amount, a control method for an assembly apparatus is provided that includes a process of assembling the flexible object to the workpiece by controlling the robot.

  According to the following disclosure, the posture of the workpiece is changed so that the normal direction matches that of the flexible object, so that the possibility that the gripping portion and the workpiece interfere with each other is reduced, and various types of flexible using the general-purpose gripping portion. Things can be handled in multiple work processes.

FIG. 1 is a functional block diagram of the assembling apparatus according to the present embodiment. FIG. 2 is a flowchart showing a method for controlling the assembling apparatus according to the present embodiment. FIG. 3 is a schematic diagram (No. 1) for explaining each step of the control method of the assembling apparatus according to the present embodiment. FIG. 4 is a schematic diagram (No. 2) for explaining each step of the control method of the assembling apparatus according to the present embodiment. FIG. 5 is a schematic diagram (No. 3) for explaining each step of the control method of the assembling apparatus according to the present embodiment. FIG. 6 is a schematic diagram (part 4) for explaining each step of the control method of the assembling apparatus according to the present embodiment. FIG. 7 is a schematic diagram (No. 5) for explaining each step of the control method of the assembling apparatus according to the present embodiment. FIG. 8 is a schematic diagram (No. 6) for explaining each step of the control method of the assembling apparatus according to the present embodiment.

  The present embodiment will be described below with reference to the drawings.

  FIG. 1 is a functional block diagram of the assembling apparatus according to the present embodiment.

  The assembling apparatus 1 is used for assembling an electronic device such as a smartphone, and includes a robot unit 2 and a control unit 3 that controls the robot unit 2.

  The robot unit 2 includes a robot 5 and a gripping unit 6 provided at the tip thereof, and the flexible object S is gripped by the gripping unit 6. Although the flexible material S is not specifically limited, the flexible sheet-like component assembled | attached to an electronic device is used as the flexible material S below. Examples of such a flexible material S include an adhesive tape that is attached to an electronic device.

  In addition, the grip portion 6 is provided with two tools 6a. The tool 6a grips the flexible object S so as to be sandwiched from both main surfaces. Note that one of the two tools 6a may be omitted and the flexible object S may be gripped by only one tool 6a.

  Further, the robot unit 2 is provided with a stage 4 that sucks and holds the workpiece W. The workpiece W is an electronic device being assembled, and is a target on which the flexible object S is assembled.

  The stage 4 has a jig 8 that holds the workpiece W and is capable of translational movement in an XY orthogonal coordinate system set in a horizontal plane. The jig 8 includes a fixed piece 9, a first slide piece 10, and a second slide piece 11. The fixed piece 9 and the first slide piece 10 have an arcuate first guide edge 9 a and a first guide edge 9 a, respectively. Two guide edges 10a are provided.

  The posture of the workpiece W can be arbitrarily controlled by the first slide piece 10 and the second slide piece 11 following the guide edges 9a and 10a.

  Further, the second slide piece 11 is provided with a turntable 12. The turntable 12 has a function of rotating the workpiece W in a plane parallel to the main surface 11 a of the second slide piece 11.

  This robot unit 2 is provided with a visual sensor 33. The visual sensor 33 is used to observe the workpiece W and the flexible object S. For example, a CCD (Charge Coupled Device) camera can be used as the visual sensor 33.

  In order to move the visual sensor 33 to a position where it is easy to observe the workpiece W and the flexible object S, the visual sensor 33 is provided with a sensor moving unit 34.

  The sensor moving unit 34 can translate the visual sensor 33 in a horizontal plane and can adjust the observation direction D of the visual sensor 33.

  On the other hand, the control unit 3 includes a physical property value input unit 21, a gripping position input unit 22, a normal direction calculation unit 23, a positional deviation calculation unit 24, a posture calculation unit 25, a movement amount calculation unit 26, and a motion calculation unit 35. . Each of these units can be realized by installing application software in a computer such as a personal computer and executing the application software in cooperation with the CPU, main memory, and the like in the computer. Further, the control unit 3 is also provided with a sensor control unit 28, a stage control unit 29, and a robot control unit 30.

  Both the physical property value input unit 21 and the gripping position input unit 22 are realized by a GUI (Graphical User Interface), and the physical property value input unit 21 receives the physical property value and shape of the flexible object S from the user. The physical property value includes, for example, the bending rigidity of the flexible material S. The shape includes, for example, the thickness of the flexible object S and the length of each side.

  On the other hand, the position of the restraint point P of the flexible object S restrained by the tool 6a and the posture of the flexible object S at the restraint point P are input to the gripping position input unit 22.

  Among these, as the position of the restraint point P, the spatial coordinates (X, Y, Z) of the restraint point P are employed. Further, the posture of the flexible object S at the restraint point P includes, for example, the tangential plane and normal direction of the flexible object S at the restraint point P.

  The normal direction calculation unit 23 calculates the normal direction n1 of the flexible object S using a finite element method as described later. As the input values of the finite element method, the physical property value of the flexible material S input from the physical property value input unit 21 and the shape before deformation, the position of the constraint point P input from the gripping position input unit 22 and the flexible material S There is a posture.

  Further, the posture calculation unit 25 calculates the change amount ΔR of the posture of the workpiece W required for the normal direction n2 of the workpiece W to coincide with the normal direction n1 of the flexible object S. As the change amount ΔR, for example, an angle α between the normal directions n1 and n2 can be adopted.

  The posture calculation unit 25 outputs the normal direction n1 of the flexible object S received from the normal direction calculation unit 23 to the movement amount calculation unit 26, and outputs the change amount ΔR to the motion calculation unit 35. To do.

  The movement amount calculation unit 26 calculates the movement amount of the visual sensor 33 required for the observation direction D of the visual sensor 33 to be parallel to the normal direction n1 based on the normal direction n1 received from the posture calculation unit 25. To do. The amount of movement includes the amount of movement (ΔX, ΔY) of the visual sensor 33 in the X direction and Y direction with respect to the position before the movement, and the amount of change Δθ in the angle of the observation direction D with respect to the position before the movement. It is.

  These movement amounts ΔX, ΔY, Δθ are output to the sensor control unit 28. Then, under the control of the sensor moving unit 28, the sensor moving unit 34 described above moves the visual sensor 33 by the respective movement amounts ΔX, ΔY, Δθ.

  On the other hand, the position deviation calculation unit 24 is based on the observation images of the workpiece W and the flexible object S observed by the visual sensor 33 after the visual sensor 33 has moved by the movement amounts ΔX, ΔY, Δθ as described above. Then, the positional deviation amount ΔL between the workpiece S and the flexible object W is calculated.

  This positional deviation amount ΔL is output to the motion calculation unit 35 as a positional deviation signal.

  The motion calculation unit 35 has a function of calculating the amount of movement of the stage 4 and the gripping unit 6 required to minimize these distances before the flexible object S is assembled to the workpiece W. This calculation is performed based on the positional deviation amount ΔL, the spatial coordinates (X, Y, Z) of the restraint point P, and the change amount ΔR of the posture of the workpiece W.

  In some cases, this function may be omitted from the motion calculation unit 35. In this case, the change amount ΔR and the positional deviation amount ΔL described above are output from the motion calculation unit 35 to the stage control unit 29.

  In response to the change amount ΔR, the stage control unit 29 controls the stage 4 to change the posture of the workpiece W by the change amount ΔR, and parallels the normal directions n1 and n2 of the flexible object S and the workpiece W, respectively. To.

  If there is the above-described positional deviation amount ΔL after the change, the stage control unit 29 translates the stage 4 so that the positional deviation is eliminated.

  Then, after the posture of the workpiece W is changed by the change amount ΔR, the robot control unit 30 controls the robot 5 to assemble the flexible object S to the workpiece W.

  Next, a control method of the assembling apparatus 1 will be described.

  FIG. 2 is a flowchart showing a method for controlling the assembling apparatus according to the present embodiment.

  3 to 8 are schematic diagrams for explaining each step of the control method.

  Hereinafter, as an example of an operation for assembling the flexible object S to the workpiece W, an operation for attaching the flexible object S such as an adhesive tape to the workpiece W will be described.

  In the first step P1 of FIG. 2, the tool 6a grips the flexible object S on the component supply base 40 under the control of the robot control unit 30, as shown in FIG.

  Next, the process proceeds to step P2.

  In step P2, the normal direction calculation unit 23 obtains the shape of the flexible object S hanging from the tool 6a as shown in FIG. 4 by the finite element method. The input values of the finite element method are the physical property value of the flexible object S, the shape before deformation, the position of the constraint point P, and the posture of the flexible object S at the constraint point P as described above.

  Here, as shown in FIG. 4, the work W is provided with a region R where the flexible object S is to be assembled. The contour of the region R is the same as that of the flexible object S. Finally, the flexible object S is attached to the workpiece W in a later step so that the contours of the region R and the flexible object S coincide with each other. Become.

  In order to facilitate the alignment between the region R and the flexible object S, in this example, a first point Q1 and a second point Q2 are set virtually on the surface of the flexible object S and the region R, respectively. . These points Q1 and Q2 correspond to each other, and when the flexible object S is attached to the workpiece W later, the points Q2 and Q2 are overlapped with each other.

  The position of the first point Q1 is not particularly limited. However, it is preferable to set the first point Q1 at the lower end of the flexible object S where the difference between the direction of the normal direction of the flexible object S at the restraint point P is the largest.

  Subsequently, the process moves to step P3, where the tangent plane F at the first point Q1 of the flexible object S is calculated as shown in FIG. 4, and the normal direction of the tangent plane F is calculated at the point Q1 of the flexible object S. Identified as line direction n1. This step is executed by the normal direction calculation unit 23 by continuously using the finite element method.

  Next, the process proceeds to step P4.

  In step P4, the posture calculation unit 25 calculates the change amount ΔR of the posture of the workpiece W required for the second normal direction n2 (see FIG. 4) of the workpiece W to coincide with the first normal direction n1. To do.

  As described above, the change amount ΔR is, for example, the angle α (see FIG. 4) between the normal directions n1 and n2.

  Next, the process proceeds to Step P5, and the posture of the workpiece W is changed by the change amount ΔR by controlling the jig 8 of the stage 4 under the control of the stage control unit 29. As a result, as shown in FIG. 5, the posture of the workpiece W is adjusted as indicated by an arrow A, and the normal directions n1 and n2 of the flexible object S and the workpiece W are parallel to each other.

  In this step, only the jig 8 of the stage 4 is moved, and the robot 5 and the tool 6a are not moved, but are fixed at one point in space. As a result, the possibility that the tool 6a interferes with the workpiece W due to the movement of the tool 6a is reduced. Therefore, a special tool 6a that does not interfere with the workpiece W is not prepared, and the shape of the flexible object S is specialized. It is possible to use a general-purpose tool 6a that is not present.

  After step P5 is completed, the process proceeds to both step P6 and step P9.

  Among these, in step P6, the movement amount calculation unit 26 calculates the current observation direction D (see FIG. 1) of the visual sensor 33.

  Then, the process proceeds to Step P7, where the movement amount calculation unit 26 moves the movement amounts ΔX and ΔY of the visual sensor 33 required for the observation direction D to be parallel to the first normal direction n1 (see FIG. 5) of the flexible object S. , Δθ is calculated. As described above, (ΔX, ΔY) is the amount of movement of the visual sensor 33 in the X direction and the Y direction with respect to the position before the movement. Δθ is a change amount of the angle in the observation direction D with respect to the position before the movement.

  Next, the process moves to step P8, and under the control of the sensor control unit 28, the sensor moving unit 34 moves the visual sensor 33 by the movement amounts ΔX, ΔY, Δθ. Thereby, the observation direction D of the visual sensor 33 becomes parallel to the first normal direction n1 of the flexible object S.

  On the other hand, in step P9, the translational movement amount ΔM of the stage 4 required to overlap each point Q1, Q2 (see FIG. 5) of the flexible object S and the workpiece W is calculated. This calculation is performed by, for example, the operation calculation unit 35.

  Next, the process moves to step P10, and the stage 4 is translated by the movement amount ΔM calculated in step P9, so that the points Q1, Q2 of the flexible object S and the workpiece W are overlapped as shown in FIG.

  At this time, since the normal directions n1 and n2 are made parallel in advance in Step P5, the angle β formed by the surfaces of the flexible object S and the workpiece W is approximately 0 °. In particular, as shown in this example, the first point Q1 is set at the lower end of the flexible object S, and the starting point in the first normal direction n1 is the lower end of the flexible object S. Is substantially parallel to the surface, and the angle β can be made as close to 0 ° as possible.

  Further, by moving the stage 4 in this way, it is not necessary to move the tool 6a or the robot 5 in order to superimpose the points Q1 and Q2, and the tool 6a can be fixed at one point in space. it can. Therefore, it is not necessary for the tool 6a to change the flexible object S so that the points Q1 and Q2 can be easily overlapped with each other, and the work time for changing can be saved.

  After performing Step P8 and Step P10 as described above, the process proceeds to Step P11.

  In step P11, as shown in FIG. 7, each of the workpiece W and the flexible object S is observed by the visual sensor 33, and the positional deviation amount ΔL between the workpiece W and the flexible object S is calculated based on the observed images. .

  The misregistration amount ΔL is calculated by the misregistration calculation unit 24 by image processing. For example, the misregistration calculation unit 24 can recognize each edge of the workpiece W and the flexible object S, and can calculate the misregistration amount ΔL based on the interval between these edges.

  In this embodiment, since the observation direction D of the visual sensor 33 is set in advance to be parallel to the first normal direction n1 of the flexible object S in step P8, the flexible object S can be captured from the front by the visual sensor 33. This makes it easy to recognize the positional deviation amount ΔL.

  In order to make it easier to recognize the displacement ΔL, the visual sensor 33 is moved so that the first point Q1 of the flexible object S is located at the center of the visual field of the visual sensor 33 without changing the observation direction D. Is preferred.

  Then, the process proceeds to Step P12, and the stage control unit 29 translates the stage 4 so that the positional deviation amount ΔL is eliminated.

  In this way, by eliminating the positional shift between the workpiece W and the flexible object S based on the observation of the visual sensor 33, the flexible object S can be assembled to the workpiece W with high accuracy in a later step.

  In order to reduce the positional deviation between the workpiece W and the flexible object S as much as possible, it is preferable to finely adjust the position of the stage 4 by performing feedback control in which steps P11 and P12 are repeated.

  Thereafter, the process proceeds to step P13, where the robot 5 is controlled under the control of the robot control unit 30, thereby attaching the flexible object S to the workpiece W as shown in FIG.

  As described above, since the angle β between the flexible object S and the workpiece W before pasting is approximately 0 °, the flexible article S hardly deforms when pasting due to contact with the workpiece W. . Therefore, in this step, it is possible to suppress the positional deviation between the workpiece W and the flexible object S due to the deformation of the flexible object S.

  8 may be provided in the robot section 2 and the flexible object S may be securely attached to the workpiece W by pressing the flexible object S from above with the pressing member 50. .

  Thus, the basic steps of the assembly apparatus control method according to the present embodiment are completed.

  In the above-described embodiment, since only the stage 4 is moved in a state where the tool 6a is fixed in order to make the normal directions n1 and n2 parallel in Step P5, the tool 6a can be used even if a general-purpose tool 6a is used. And the work W are less likely to interfere.

  Therefore, it is possible to use one tool 6a in common in a plurality of processes for manufacturing electronic devices and different types of electronic devices, and it is not necessary to use a dedicated tool 6a for each type of process or flexible object S. Time and effort for exchanging 6a can be saved.

  The following additional notes are disclosed for each embodiment described above.

(Appendix 1) A stage that can adjust the posture of the workpiece,
A robot having a gripping part for gripping a flexible object;
A normal direction calculation unit for calculating a first normal direction of the flexible object;
A posture calculation unit for calculating a change amount of the posture of the workpiece required for the second normal direction of the workpiece to coincide with the first normal direction;
A stage control unit that changes the posture of the workpiece by the change amount by controlling the stage;
After the posture of the workpiece is changed by the change amount, a robot controller that assembles the flexible object to the workpiece by controlling the robot;
An assembling apparatus.

(Supplementary Note 2) The first normal direction is a normal direction at a first point on the surface of the flexible object,
The assembly apparatus according to appendix 1, wherein the second normal direction is a normal direction at a second point superimposed on the first point on the surface of the workpiece.

  (Supplementary Note 3) The normal direction calculation unit obtains a tangent plane of the flexible object at the first point, and identifies the normal direction of the tangent plane as the first normal direction. The assembly apparatus according to Appendix 2.

  (Supplementary note 4) The assembly apparatus according to any one of Supplementary notes 1 to 3, wherein the normal direction calculation unit calculates the first normal direction by a finite element method.

(Supplementary Note 5) A visual sensor for observing the workpiece and the flexible object;
A sensor moving unit for moving the visual sensor;
A movement amount calculation unit for calculating a movement amount of the visual sensor required for the observation direction of the visual sensor to be parallel to the first normal direction;
A sensor controller that moves the visual sensor by the amount of movement by controlling the sensor moving unit;
A positional deviation for calculating a positional deviation amount between the workpiece and the flexible object based on respective observation images of the workpiece and the flexible object observed by the visual sensor after the visual sensor is moved by the movement amount. A calculation unit,
The assembly apparatus according to any one of appendix 1 to appendix 4, wherein the stage control unit moves the stage so that the positional deviation is eliminated.

(Additional remark 6) The process which calculates the 1st normal line direction of the flexible object hold | gripped by the holding part of the robot,
Processing for calculating a change amount of the posture of the work required for the second normal direction of the work held on the stage to coincide with the first normal direction;
By changing the posture of the workpiece by the change amount by controlling the stage,
After changing the posture of the work by the change amount, the robot is controlled to assemble the flexible object to the work;
A method for controlling an assembling apparatus.

(Supplementary Note 7) As the first normal direction, the normal direction at the first point on the surface of the flexible object is adopted,
7. The method of controlling an assembling apparatus according to appendix 6, wherein a normal direction at a second point superimposed on the first point on the surface of the workpiece is adopted as the second normal direction.

  (Supplementary Note 8) In the process of calculating the first normal direction, the tangent plane of the flexible object at the first point is obtained, and the normal direction of the tangent plane is identified as the first normal direction. The method of controlling an assembling apparatus according to appendix 7, wherein

  (Supplementary note 9) In the process of calculating the first normal direction, the first normal direction is calculated by a finite element method. The assembly apparatus according to any one of supplementary notes 6 to 8, Control method.

(Additional remark 10) The process which calculates the moving amount | distance of the said visual sensor required for the observation direction of the visual sensor which observes the said workpiece | work and the said flexible material to become parallel to the said 1st normal line direction,
A process of moving the visual sensor by the amount of movement;
A process of calculating a positional deviation amount between the workpiece and the flexible object based on respective observation images of the workpiece and the flexible object observed by the visual sensor after moving the visual sensor by the movement amount; ,
The method of controlling an assembling apparatus according to any one of appendix 6 to appendix 9, further comprising a process of moving the stage so as to eliminate the displacement.

DESCRIPTION OF SYMBOLS 1 ... Assembly apparatus, 2 ... Robot part, 3 ... Control part, 4 ... Stage, 5 ... Robot, 6 ... Holding part, 6a ... Tool, 8 ... Jig, 9 ... Fixed piece, 9a ... 1st guide edge, DESCRIPTION OF SYMBOLS 10 ... 1st slide piece, 10a ... 2nd guide edge, 11 ... 2nd slide piece, 11a ... Main surface, 12 ... Turntable, 21 ... Physical property value input part, 22 ... Gripping position input part, 23 ... Normal direction calculation unit, 24 ... Position displacement calculation unit, 25 ... Posture calculation unit, 26 ... Movement amount calculation unit, 28 ... Sensor control unit, 29 ... Stage control unit, 30 ... Robot control unit, 40 ... Component supply table, 50: pressing member, S: flexible object, W: work, n1, n2: first and second normal directions, Q1, Q2: first and second points, F: tangential plane, D: observation direction.

Claims (5)

A stage that can adjust the posture of the workpiece,
A robot having a gripping part for gripping a flexible object;
A normal direction calculation unit for calculating a first normal direction of the flexible object;
A posture calculation unit for calculating a change amount of the posture of the workpiece required for the second normal direction of the workpiece to coincide with the first normal direction;
A stage control unit that changes the posture of the workpiece by the change amount by controlling the stage;
After the posture of the workpiece is changed by the change amount, a robot controller that assembles the flexible object to the workpiece by controlling the robot;
An assembly apparatus.   The assembly apparatus according to claim 1, wherein the normal direction calculation unit calculates the first normal direction by a finite element method. A visual sensor for observing the workpiece and the flexible object;
A sensor moving unit for moving the visual sensor;
A movement amount calculation unit for calculating a movement amount of the visual sensor required for the observation direction of the visual sensor to be parallel to the first normal direction;
A sensor controller that moves the visual sensor by the amount of movement by controlling the sensor moving unit;
A positional deviation for calculating a positional deviation amount between the workpiece and the flexible object based on respective observation images of the workpiece and the flexible object observed by the visual sensor after the visual sensor is moved by the movement amount. A calculation unit,
The assembly apparatus according to claim 1, wherein the stage control unit moves the stage so that the positional deviation is eliminated. Processing to calculate a first normal direction of the flexible object gripped by the gripping portion of the robot;
Processing for calculating a change amount of the posture of the work required for the second normal direction of the work held on the stage to coincide with the first normal direction;
By changing the posture of the workpiece by the change amount by controlling the stage,
After changing the posture of the work by the change amount, the robot is controlled to assemble the flexible object to the work;
A method for controlling an assembling apparatus. A process of calculating the amount of movement of the visual sensor required for the observation direction of the visual sensor observing the workpiece and the flexible object to be parallel to the first normal direction;
A process of moving the visual sensor by the amount of movement;
A process of calculating a positional deviation amount between the workpiece and the flexible object based on respective observation images of the workpiece and the flexible object observed by the visual sensor after moving the visual sensor by the movement amount; ,
The method of controlling an assembling apparatus according to claim 4, further comprising a process of moving the stage so that the displacement is eliminated.

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