JP2009220248A - Robot installation method and robot production system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a robot installation method capable of completing a teaching operation accurately in a short time without preparing dedicated jigs and tools and to provide a robot production system. <P>SOLUTION: The position of a work 40 is detected according to the image obtained by photographing the area including the work 40, and a carrying robot 30 is moved toward the work 40 according to the position of the work 40 detected from the image. Calculation is performed according to the force applied to the conveying robot 30 when the holding hand of the carrying robot 30 is brought into contact with the work 40 to hold the work 40 by the conveying robot 30. The holding hand 32 is fitted to the work 40 along the work, and the position of the work 40 is detected. The carrying robot 30 is controlled according to the detected position of the work 40. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a robot installation method for automatically teaching a position of a workpiece to a robot production system and installing the robot production system, and to a robot production system in which installation work including such teaching is automated.

  Conventionally, in order to assemble precision parts, a robot production system has been proposed in which a workpiece is gripped and moved, and this workpiece is assembled to another workpiece. In such a robot production system, it is necessary to accurately teach the hand position of the robot. That is, the robot production system needs to accurately teach the hand position on the premise that the robot production system is firmly fixed at a predetermined position and the workpiece is also accurately positioned at the predetermined position. This is because the work placed at a predetermined position cannot be gripped unless the hand position is correctly taught.

  As a technique for accurately performing such teaching, for example, Patent Document 1 discloses a part on a workpiece corresponding to at least one teaching point among teaching points for which position data is given on a teaching program. A mark that can be identified by the camera is applied to the camera, the position of the mark is measured by a camera mounted on the robot, and a three-dimensional correction amount of the position data of at least one teaching point is obtained based on the measurement result of the mark position. A method for obtaining a three-dimensional position correction amount of teaching position data to be obtained is described.

  Further, in Patent Document 2, in a robot, a plurality of workpieces and an assembly tool are used as objects to be loaded, and each of the objects to be loaded is carried from the outside of the movable range of the robot to the inside of the movable range. And the assembly tool after use as an object to be unloaded, and a transport means for unloading each unloaded object from the inside of the movable range to the outside of the movable range, so that the assembly tool can be replaced without relying on human hands. Thus, there is described an apparatus which can efficiently produce a variety of products in small quantities.

  In Patent Document 3, a 6-axis force sensor is provided on the wrist axis of a robot manipulator, and when a calibration point is taught using a robot system that performs impedance control, a jig having a circular hole is used as a fixed point. Prepare a rod that can be inserted into the circular hole of this jig as a tool and attach it to the wrist axis of the robot manipulator.The tip of this tool is the control point of the robot manipulator, and the robot's circular hole is inserted into the circular hole of the jig. It is described that a fixed point is observed by inserting a rod as a tool, and position information and posture information of a robot control point are used as calibration information.

Japanese Patent No. 3665353 Japanese Patent No. 3673117 JP-A-5-111886

  In conventional robot production systems, the work load on the site operator, such as workpiece positioning and teaching operations, is large. Especially, when the workpieces are diversified, the number of times of positioning and teaching increases. The problem is that the productivity of the entire automatic production work by the system is lowered.

  In the techniques described in Patent Documents 1 to 3 described above, dedicated jigs and assembly tools must be prepared or marked, and teaching work cannot be facilitated sufficiently. .

  Therefore, the present invention has been made in view of the above circumstances, and the purpose thereof is a robot that can complete a highly accurate teaching operation in a short time without the need to prepare a dedicated jig or tool. It is to provide an installation method and a robot production system.

  In order to solve the above-described problems and achieve the object, the present invention has any one of the following configurations.

[Configuration 1]
The robot installation method according to the present invention is a robot installation method for installing a robot production system having a gripping hand that grips a workpiece and moves the workpiece to a predetermined position. The position of the workpiece is detected based on the captured image, the gripping hand is moved toward the workpiece according to the position of the workpiece detected from the image, and the gripping hand and the workpiece are Detects the force received by the gripping hand when it comes in contact, calculates based on the force received by the gripping hand, closely contacts the workpiece with the gripping hand, detects the position of the workpiece, The position is stored, and the robot arm is controlled based on the stored position of the workpiece.

  That is, in this robot installation method, position correction (teaching) by the robot production system is automated by performing detection based on the image and detection based on the force for correcting the positional deviation between the robot production system and the workpiece. can do. The detection based on the image enables coarse alignment with an accuracy of ± 1 mm or less, and the detection based on force enables the precise alignment with an accuracy of ± 0.1 mm or less.

  Also, with this robot installation method, even when the workpiece is transported by the work tray, the positional deviation between the robot production system and the work tray can be corrected, so the same automation as when the workpiece is transported as it is is possible. It is.

[Configuration 2]
The robot production system according to the present invention is a robot production system having a gripping hand that grips a work and moves the work to a predetermined position. The position of the work is based on an image obtained by imaging an area including the work. An imaging means for detecting the position, a control means for controlling the robot arm according to a detection result by the imaging means, and a gripping hand moves toward the workpiece and grips when the workpiece whose position is detected by the imaging means is about to be gripped. The force sensor that detects the force received by the gripping hand when the hand and the workpiece come into contact with each other, and the calculation is based on the force detected by the force sensor. And a storage means for storing the detected position of the workpiece. The control means is stored by the storage means. It is characterized in that for controlling the robot arm based on the position of the workpiece.

  That is, in this robot production system, the position correction (teaching) by the robot production system is automated by providing an imaging means and a force sensor for correcting the positional deviation between the robot production system and the workpiece. Coarse positioning with an accuracy of ± 1 mm or less is possible by the imaging means, and precise positioning with an accuracy of ± 0.1 mm or less is possible by the force sensor.

  Also, in this robot production system, even when a workpiece is transported by the work tray, the positional deviation between the robot production system and the work tray can be corrected, so that the same automation as when the workpiece is transported as it is is possible. It is.

  The robot installation method according to the present invention includes the configuration 1, and performs detection based on an image and detection based on a force for correcting a positional deviation between the robot production system and a workpiece installed at a predetermined position. Teaching by the robot production system can be automated.

  In addition, the robot production system according to the present invention has the configuration 2, and thus includes an imaging unit, a force sensor, and a storage unit for correcting a positional deviation between the robot production system and a workpiece installed at a predetermined position. By providing, the position of the workpiece detected by the force sensor is stored, and the control unit controls the robot arm based on the storage by the storage unit, so that the teaching by the robot production system is automated.

  In the present invention, since a dedicated jig for positioning the workpiece is not necessary, in the same assembly line as the worker, for example, in the time zone when the worker does not work, Automatic production can be performed using the same jigs, tools, work tables, and automatic devices that the user has used.

  Further, in the robot production system according to the present invention, since accurate positioning is not necessary, installation work on the production line is easy. Furthermore, this robot production system can change the arrangement between the state installed on the production line and the state removed from the production line. For example, in a production line in which a worker performs work during the day, the robot production system according to the present invention is installed on the production line at night so that it can be easily switched to fully automatic production. Further, even when the layout of the production line is changed, the installation work of the robot production system on the production line is easy, so it can be easily handled.

  That is, the present invention can provide a robot installation method and a robot production system capable of completing a highly accurate teaching operation in a short time without the need to prepare a dedicated jig or tool.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 to 4 show a first embodiment of a robot production system according to the present invention, FIG. 1 is a schematic perspective view of the robot production system, FIG. 2 is a block diagram of the robot production system, and FIG. FIG. 4 is a schematic perspective view of the installation state of the robot production system.

  As shown in FIG. 1, the robot production system 1A includes first, second, and third work tables T1, T2, and T3 that can be repositioned and arranged at close positions, and the first, second, and second work tables. Three pedestals 10, 10, 10 installed at predetermined positions on the three work tables T1, T2, T3, and a conveying jig 20 that can be selectively placed on the three pedestals 10, 10, 10, The transfer robot 30 installed on the first work table T1, and the first, second, and third work that are installed on the first, second, and third work tables T1, T2, and T3, respectively, and perform operations such as assembly. Work robots R1, R2, and R3 are provided. Among these, the first work table T1 and the transfer robot 30 installed on the first work table T1 constitute a robot production system according to the present invention. Note that the robot production system according to the present invention may be configured without the first work robot R1.

  The transfer robot 30 includes a multi-joint arm unit 31 which is a hand moving unit whose lower end is fixed to the first work table T1, a gripping hand 32 attached to the tip of the multi-joint arm unit 31, and a gripping hand 32. And a gripping position recognizing unit having a camera 33 which is an imaging unit fixed in the vicinity.

  As shown in FIG. 2, the multi-joint arm unit 31 swings and rotates each joint by a drive signal from the control unit 51, thereby moving the position of the gripping hand 32 to a predetermined position. The image signal from the camera 33 is sent to the image processing unit 52 and further sent to the control unit 51. The camera 33, the image processing unit 52, and the control unit 51 constitute a gripping position recognition unit. A force sensor 53 described later is attached to the gripping hand 32. An output signal from the force sensor 53 is sent to the control unit 51.

  The control unit 51 is built in the first work table T1, and has an integral structure that can be transported together with the first work table T1.

  As shown in detail in FIG. 3, the gripping hand 32 includes a hand base portion 35 that is rotatably attached to the tip of the articulated arm portion 31, and a pair of hand pieces 36 provided below the hand base portion 35. 36. The pair of hand pieces 36, 36 includes an upper surface portion 36a that moves along the hand base portion 35, a side surface portion 36b that is suspended from the upper surface portion 36a, and a lower surface portion 36c that protrudes inward from the lower end of the side surface portion 36b. It consists of and. Guide tapered surfaces 37 are formed at both ends of each upper surface portion 36a.

  The pair of hand pieces 36 and 36 are movable in a direction to widen and narrow the distance between each other, and a hand open position that allows entry into the robot grip 23 and a hand closed position that grips the robot grip 23. Can be located.

  The gripping position recognition unit recognizes the gripping position from the image information of the position recognition visual marker 24 photographed by the camera 33. The grip position information is sent to the control unit 51, and the control unit 51 controls the driving of the articulated arm unit 31 based on the grip position information.

  The first to third work robots R1, R2, and R3 use the work holding position of the transfer jig 20 placed on the bases 10, 10, and 10 of the work tables T1, T2, and T3 as work positions. Then, the first, second, and third work robots R1, R2, and R3 perform predetermined work on the work 40, respectively, at the taught work positions.

  The transfer robot 30 is provided with a force sensor 53. The force sensor 53 moves the gripping hand 32 of the transport robot 30 when the transport robot 30 moves toward the work 40 and tries to grip the work 40 whose position is detected based on the image obtained by the camera 33. And the workpiece 40 are in contact with each other, the force received by the gripping hand 32 is detected. The force detected by the force sensor 53 is sent to the control means 51. The control means 51 performs calculation based on force, and detects the position of the workpiece 40 by bringing the gripping hand 32 into close contact with the workpiece 40 as shown in FIG.

  And the control apparatus 51 memorize | stores the position of the detected workpiece | work 40, and controls the conveyance robot 30 after this based on this memory | storage. That is, teaching to the transfer robot 30 is automatically performed. The transfer robot 30, the first, second, and third work robots R1, R2, and R3 are not vertical articulated robots, and may take any form such as a horizontal articulated robot or an orthogonal axis robot.

  FIG. 4 is a schematic perspective view of the installation state of the robot production system according to the present invention.

  This robot production system grips the work 40 placed on the first work table T1, moves it onto the second and third work tables T2 and T3, and moves the work placed on the respective work tables. It is possible to perform a predetermined operation on the. At this time, since the teaching based on the image obtained by the camera 33 and the force detected by the force sensor 53 is performed prior to the work, the first work in which the transport robot 30 is placed and fixed as shown in FIG. The position of the table T1 does not need to be accurately installed. In FIG. 4, the position of the first work table T <b> 1 is an accurate position indicated by the alternate long and short dash line, and the position indicated by the solid line indicates a misaligned state.

  Therefore, the robot production system can freely change the arrangement between the state installed on the production line and the state removed from the production line. For example, in a production line in which a worker performs work during the day, the robot production system according to the present invention is installed on the production line at night so that it can be easily switched to fully automatic production. That is, prior to starting full-automatic production, the work 40 placed on the work table T1 can be accurately gripped and moved by performing the teaching as described above. Further, even when the layout of the production line is changed, the installation work of the robot production system on the production line is easy, so it can be easily handled.

  FIG. 5 is a flowchart showing a procedure for detecting the position of the workpiece 40 in this robot production system.

  The robot production system according to the present invention configured as described above detects the position of the workpiece 40 and automatically performs a teaching operation as shown in FIG. That is, as shown in FIG. 5, when starting the operation in S <b> 11, the control unit 51 proceeds to S <b> 12 and starts measuring the position of the workpiece 40 based on the image data obtained by the camera 33. Next, in S <b> 13, the gripping hand 32 of the transfer robot 30 is approached toward the work 40 based on the measurement result.

  In S14, the workpiece 40 is gripped by the gripping hand 32 of the transfer robot 30, and the force received by the gripping hand 32 coming into contact with the workpiece 40 is detected. Thus, the position of the workpiece 40 is accurately detected. Next, in S15, the detected position of the workpiece 40 is stored.

  Proceeding to S16, the teaching data is corrected based on the stored position of the workpiece 40. By this correction, automatic teaching is performed. Then, the process proceeds to S17 and the automatic teaching is finished. Thereafter, the control unit 51 controls the transport robot 30 based on the corrected teaching data.

  FIG. 6 is a flowchart showing an operation method of this robot production system.

  As described above, the robot production system according to the present invention configured as described above is installed and used in a production line where work is normally performed by an operator as shown in FIG. Can be provided.

  That is, as shown in FIG. 6, when the operation of the robot production system is started in S21, the process proceeds to S22, and this robot production system is arranged on the production line where the work of the worker is completed as a substitute for the worker. . In S23, the control unit 51 automatically corrects the positional deviation between the first work table T1 and the production line according to the teaching data correction procedure shown in FIG. Here, the production line may be the second and third work tables T2 and T3 described above, or may be other work tables. Then, the process proceeds to S24, and automatic production by the robot production system is started.

  When the automatic production is finished in S25, the process proceeds to S26, where the robot production system is removed from the production line and carried out. At this time, it becomes a state where the work by a normal worker can be started. Then, the process proceeds to S27, and the operation of the robot production system is terminated.

1 is a schematic perspective view of a robot production system according to the present invention. 1 is a block diagram of a robot production system according to the present invention. It is a perspective view of the holding hand and camera of a conveyance robot. It is a schematic perspective view of the installation state of the robot production system concerning the present invention. 5 is a flowchart showing a procedure for specifying a position of a workpiece in the robot production system according to the present invention. It is a flowchart which shows the operation method in the robot production system which concerns on this invention.

Explanation of symbols

30 transfer robot T1 first work table 33 camera 40 work 51 control means 53 force sensor

Claims (2)

In a robot installation method for installing a robot production system having a robot arm equipped with a gripping hand that grips a workpiece and moves the workpiece to a predetermined position.
The area including the workpiece is imaged, and based on the obtained image, the position of the workpiece is detected,
Depending on the position of the workpiece detected from the image, the gripping hand is moved toward the workpiece,
When the gripping hand and the work come into contact with each other when the gripping hand is about to hold the work, the force received by the gripping hand is detected.
Performing a calculation based on the force received by the gripping hand, closely contacting the gripping hand with the workpiece and detecting the position of the workpiece;
Storing the detected position of the workpiece;
A robot installation method, wherein the robot arm is controlled based on the stored position of the workpiece. In a robot production system having a gripping hand that grips a workpiece and moves the workpiece to a predetermined position.
Imaging means for imaging an area including the workpiece and detecting the position of the workpiece based on the obtained image;
Control means for controlling the robot arm according to a detection result by the imaging means;
When the gripping hand moves toward the workpiece and tries to grip the workpiece whose position is detected by the imaging means, the gripping hand receives when the gripping hand and the workpiece come into contact with each other. A force sensor for detecting force;
A calculation means for performing a calculation based on the force detected by the force sensor and detecting the position of the workpiece by causing the gripping hand to follow the workpiece and closely contact the workpiece;
Storage means for storing the detected position of the workpiece,
The said control means controls the said robot arm based on the position of the said workpiece | work memorize | stored by the said memory | storage means. The robot production system characterized by the above-mentioned.

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