Industrial robot and method of controlling an industrial robot

Abstract

The present application provides an industrial robot, even if the position and orientation of a carrying object placed in a receiving part in the horizontal direction are corrected, the carrying time of the carrying object from the receiving part to the delivery part can be shortened. The industrial robot (1) obtains the position data of the hand (6) in the Y direction when the two detection mechanisms (33) respectively detect the carrying object (2) (first position data, second position data) when performing the first action of moving the hand (6) to the receiving part (4), obtains the position data of the carrying object (2) in the X direction detected by the detection mechanism (34) (third position data) when performing the second action of moving the hand (6) that has received the carrying object (2) by the receiving part 4 in a manner close to the main body part (10), and corrects the position and orientation of the hand (6) based on the first to third position data when performing the third action of moving the hand (6) loaded with the carrying object (2) to the delivery part (5).

Description

Technical Field

[0001] This invention relates to an industrial robot for transporting objects formed in a rectangular or square shape. Furthermore, this invention relates to a control method for such an industrial robot. Background Technology

[0002] Previously, a robot for transporting glass substrates between boxes was known (for example, see Patent Document 1). The robot described in Patent Document 1 includes a horizontal moving part, a robot hand, and a connecting part connecting the horizontal moving part and the robot hand. The horizontal moving part has a slider that moves in a left-right direction along a guide rail. The robot hand includes: a first arm rotatably connected to the connecting part; a second arm rotatably connected to the front end of the first arm; and a hand rotatably connected to the front end of the second arm, and for loading the glass substrate.

[0003] In the robot described in Patent Document 1, two first distance sensors for detecting the distance between the hand and the front end face of a glass substrate are mounted on the upper surface of the hand. The two first distance sensors are arranged with a gap in the left-right direction. A position detection sensor is mounted on the connecting part via a support arm, which is used to detect the position of the left end face of the glass substrate mounted on the hand positioned at the origin.

[0004] The robot described in Patent Document 1 is equipped with a control device. Based on the detection results of two first distance sensors, the control device calculates a correction amount corresponding to the forward / backward offset of the glass substrate placed inside the box relative to a reference position, and a correction amount corresponding to the tilt of the glass substrate placed inside the box relative to the reference position when viewed from above or below. Furthermore, based on the detection results of a position detection sensor, the control device calculates a correction amount corresponding to the left / right offset of the glass substrate mounted on the hand relative to the reference position.

[0005] Patent Document 1 describes a robot that, before loading a glass substrate placed in a box onto its hand, corrects the orientation and position of the hand in the front-back direction based on correction amounts corresponding to the offset of the glass substrate relative to a reference position in the front-back direction and correction amounts corresponding to the tilt of the glass substrate relative to the reference position. Furthermore, when the robot moves the glass substrate loaded onto the hand into the box for the next process, it corrects the position of the hand in the left-right direction based on correction amounts corresponding to the offset of the glass substrate relative to the reference position in the left-right direction.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 9-162257 Summary of the Invention

[0009] The technical problem that the invention aims to solve

[0010] In the robot described in Patent Document 1, in order to place the glass substrate in the next process box after correcting its horizontal position and orientation within the box, the orientation and position of the hand are corrected in both cases: when receiving and removing the glass substrate from the box, and when moving the glass substrate into the next process box and handing it over. Therefore, in the case of this robot, the time required to move the glass substrate between boxes may become longer.

[0011] For example, when receiving and removing a glass substrate from a box, if the hand is moved directly with the corrected orientation, there is a possibility that the glass substrate loaded on the hand or the hand may interfere with the components of the box. In order to prevent interference between the glass substrate or the hand and the components of the box, the orientation of the hand needs to be temporarily changed before moving the hand out of the box. In this case, the time required to move the glass substrate between boxes becomes longer.

[0012] Therefore, the technical problem of the present invention is to provide an industrial robot that moves a transport object from a designated receiving section to a designated transfer section, and can shorten the transport time of the transport object from the receiving section to the transfer section even after correcting the horizontal position and orientation of the transport object placed in the receiving section.

[0013] Furthermore, the technical problem of the present invention is to provide a control method for an industrial robot, wherein, in an industrial robot that moves a transport object from a designated receiving section to a designated transfer section, even if the transport object is placed on the transfer section after correcting the horizontal position and orientation of the transport object placed on the receiving section, the transport time of the transport object from the receiving section to the transfer section can be shortened.

[0014] Technical solutions adopted to solve technical problems

[0015] To solve the above-mentioned technical problems, the industrial robot of the present invention is an industrial robot for transporting objects formed in a rectangular or square shape, characterized in that it includes: a hand for loading the object and capable of moving in a horizontal direction; an arm connected to the hand; a main body rotatably connected to the arm with the vertical direction as the axis of rotation; two optical first detection mechanisms mounted on the hand; and an optical second detection mechanism mounted on the main body.And a control unit for controlling industrial robots; and if the hand position when loading and receiving a transport object placed on a predetermined receiving part while the hand tip is moving away from the main body is set as the receiving position, and the hand position when transferring the transport object loaded on the hand to a predetermined transfer part while the hand tip is moving away from the main body is set as the transfer position, then a first action, a second action, and a third action are performed. The first action is the action of moving the hand tip away from the main body to the receiving position, and the second action is the action of moving the hand tip towards the main body after the first action, when the hand that has received the transport object at the receiving position moves after the first action. The third action is the movement of the hand carrying the object to be transported moving away from the main body at the tip of the hand after the second action. When the industrial robot performs the first and second actions, the hand moves linearly relative to the main body in a certain direction. If the direction of the hand's movement during the first and second actions is defined as the first direction, and the direction orthogonal to the first and vertical directions is defined as the second direction, then the first detection mechanism is a reflective detection mechanism including a first light-emitting part and a first light-receiving part. The first light-receiving part receives light emitted from the first light-emitting part and reflected by the object to be transported. The two first detection mechanisms are arranged spaced apart in the second direction. The second detection mechanism is a transmissive detection mechanism with a second light-receiving part and a second light-emitting part. The second light-receiving part is composed of a line sensor or a region sensor. The second light-emitting part is positioned opposite the second light-receiving part at a predetermined interval in the vertical direction. When the industrial robot performs a first action, the two first detection mechanisms pass under the transport object placed on the receiving part. When the industrial robot performs a second action, one end face of the transport object loaded on the hand passes between the second light-receiving part and the second light-emitting part. When the industrial robot performs the first action, the control unit acquires first position data and second position data. The first position data is obtained by the two first detection mechanisms. A first detection mechanism in the structure detects the position data of the hand in a first direction when the object is being transported. The second position data is the position data of the hand in the first direction detected by the other of the two first detection mechanisms. Furthermore, when the industrial robot performs a second action, third position data is acquired. This third position data is the position data of one end face of the object in the second direction, detected by the second detection mechanism, when the hand moves to a predetermined measurement position. Finally, when the industrial robot performs a third action, based on the first, second, and third position data, the horizontal position and orientation of the hand when reaching the handover position are corrected.

[0016] In addition, to solve the above-mentioned technical problems, the present invention provides a control method for an industrial robot, the industrial robot comprising: a hand for loading a transport object formed in a rectangular or square shape and capable of moving in a horizontal direction; an arm connected to the hand; a main body connected to the arm in a rotatable manner; and two optical first detection mechanisms mounted on the hand.The optical second detection mechanism is installed on the main body. If the hand position when loading and receiving a transport object placed on a predetermined receiving portion while the hand tip is moving away from the main body is defined as the receiving position, and the hand position when transferring the transport object loaded on the hand to a predetermined transfer portion while the hand tip is moving away from the main body is defined as the transfer position, then the first, second, and third actions are performed. The first action is the action of moving the hand tip away from the main body to the receiving position. The second action is after the first action, when the hand receiving the transport object at the receiving position approaches the receiving portion with its tip... The third action is the movement of the hand carrying the object to be transported when it moves away from the main body after the second action. The hand moves linearly relative to the main body in a certain direction during the first and second actions. If the direction of hand movement during the first and second actions is defined as the first direction, and the direction orthogonal to the first direction and the vertical direction is defined as the second direction, then the first detection mechanism is a reflective detection mechanism including a first light-emitting part and a first light-receiving part that receives light emitted from the first light-emitting part and reflected by the object to be transported. The two first detection mechanisms are spaced apart in the second direction. In the configuration, the second detection mechanism is a transmissive detection mechanism having a second light-receiving part composed of a line sensor or a region sensor and a second light-emitting part arranged opposite to the second light-receiving part in a vertical direction at a predetermined interval. During the first action, the two first detection mechanisms pass under the transported object placed on the receiving part. During the second action, one end face of the transported object loaded on the hand passes between the second light-receiving part and the second light-emitting part. The control method for the industrial robot is characterized in that, during the first action, first position data and second position data are acquired, where the first position data is derived from the two first detection mechanisms. A first detection mechanism within the system detects the position data of the hand in a first direction when handling an object. A second position data is obtained from the position data of the hand in the first direction detected by the other of the two first detection mechanisms. Furthermore, during a second action, third position data is acquired. This third position data is the position data of one end face of the object in the second direction, detected by the second detection mechanism, when the hand moves to a predetermined measurement position. Finally, during the third action, the horizontal position and orientation of the hand upon reaching the handover position are corrected based on the first, second, and third position data.

[0017] In this invention, when the industrial robot performs its third action, the horizontal position and orientation of the hand upon reaching the handover position are corrected based on the first, second, and third position data. That is, in this invention, the horizontal position and orientation of the hand are corrected only during the third action—the action of moving the hand carrying the transported object to the handover position with the tip of the hand moving away from the main body—and not during the first action—the action of moving the hand to the receiving position with the tip of the hand moving away from the main body. Therefore, in this invention, even if the horizontal position and orientation of the transported object placed on the receiving part are corrected before placing it on the handover part, the transport time from the receiving part to the handover part can be shortened.

[0018] In this invention, for example, the arm is composed of a plurality of arm parts that are rotatably connected to each other and can be extended and retracted in the horizontal direction. The hand is rotatably connected to the front end of the arm, and the base end of the arm is rotatably connected to the main body.

[0019] In this invention, an industrial robot includes, for example, an arm drive mechanism that extends and retracts the arm by moving the hand linearly relative to the main body in a certain direction; a rotation mechanism that rotates the main body; and a horizontal movement mechanism that moves the main body in a left-right direction orthogonal to the vertical direction. When the industrial robot performs a third action, the hand moves linearly relative to the main body in a front-back direction orthogonal to the vertical and left-right directions. When the industrial robot performs the third action, the control unit controls the arm drive mechanism, the rotation mechanism, and the horizontal movement mechanism based on first position data, second position data, and third position data to correct the position and orientation of the hand in the horizontal direction when reaching the handover position.

[0020] In this invention, for example, the first direction is consistent with the left-right direction. When the industrial robot performs the first and second actions, the hand moves linearly relative to the main body in the left-right direction. If the main body cannot move in the front-back direction, the orientation of the hand cannot be properly corrected when performing the first action. However, in this invention, even if the orientation of the hand cannot be properly corrected when performing the first action, the orientation of the hand can be properly corrected when performing the third action.

[0021] In this invention, the first direction is consistent with the front-back direction. When the industrial robot performs the first action and the second action, the hand can also move linearly in the front-back direction relative to the main body.

[0022] Invention Effects

[0023] As described above, in the present invention, in an industrial robot that moves a transport object from a designated receiving section to a designated transfer section, even if the transport object is placed on the transfer section after correcting the horizontal position and orientation of the transport object placed on the receiving section, the transport time for moving the transport object from the receiving section to the transfer section can be shortened. Attached Figure Description

[0024] Figure 1 This is a top view of an industrial robot according to an embodiment of the present invention.

[0025] Figure 2 yes Figure 1 Top views of the industrial robot in different states are shown.

[0026] Figure 3 yes Figure 1 The rear view of the industrial robot shown.

[0027] Figure 4 It is used for explanation Figure 1 The diagram shown is a block diagram of the structure of an industrial robot.

[0028] Figure 5 It is used to explain in Figure 1 The diagram shows the calculation method for the correction values ​​of the hand's position and orientation in the left and right directions when the industrial robot performs the third action.

[0029] Explanation of reference numerals in the attached figures

[0030] 1… Robot (industrial robot); 2… Substrate (glass substrate, object to be transported); 3, 4… Storage box (receiving part); 5… Processing device (transfer part); 6, 7… Hand; 8, 9… Arm; 10… Main body; 21… First arm (arm); 22… Second arm (arm); 27, 28… Arm drive mechanism; 29… Rotation mechanism; 31… Horizontal movement mechanism; 32… Control unit; 33… Detection mechanism (first detection mechanism); 34… Detection mechanism (second detection mechanism); 37… Light-emitting part (first light-emitting part); 38… Light-receiving part (first light-receiving part); 39… Light-emitting part (second light-emitting part); 40… Light-receiving part (second light-receiving part); X… Front-back direction; Y… Left-right direction. Detailed Implementation

[0031] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0032] (Structure of industrial robots)

[0033] Figure 1 This is a top view of an industrial robot 1 according to an embodiment of the present invention. Figure 2 yes Figure 1Top views of the industrial robot 1 in different states. Figure 3 yes Figure 1 The rear view of industrial robot 1 shown. Figure 4 It is used for explanation Figure 1 The diagram shows a block diagram of the structure of the industrial robot 1.

[0034] The industrial robot 1 (hereinafter referred to as "robot 1") in this embodiment is, for example, a horizontal multi-joint robot that transports a glass substrate 2 for an organic EL display or a glass substrate 2 for a liquid crystal display (hereinafter referred to as "substrate 2"), which is the object to be transported. The substrate 2 is formed into a rectangular or square flat plate. The robot 1, for example, transports the substrate 2 from storage boxes 3 and 4 that hold multiple substrates 2 to a processing apparatus 5 that performs a predetermined processing on the substrate 2. That is, the robot 1, for example, removes the substrate 2 from the storage boxes 3 and 4 and moves the substrate 2 removed from the storage boxes 3 and 4 into the processing apparatus 5.

[0035] In the following explanation, the direction orthogonal to the up and down directions will be used. Figure 1 The Y-direction of the equation is set to the "left-right direction", which is orthogonal to the up-down and left-right directions. Figure 1 The X-direction is set to the "front-back direction". Additionally, the left-right direction is set to... Figure 1 The Y1 direction side is set as the "right" side, and its opposite side is... Figure 1 The Y2 direction side is set as the "left" side, and the front-back direction side is set as the "left" side. Figure 1 The X1 direction side is set as the "front" side, and its opposite side is... Figure 1 The X2 direction side is set as the "rear" side.

[0036] Multiple substrates 2 are stacked and arranged in storage boxes 3 and 4, spaced apart vertically. In this embodiment, storage box 3 is located at the front of robot 1, and storage box 4 is located at the right side of robot 1. The processing device 5 is located at the rear of robot 1. The end faces of the substrates 2 stored in storage boxes 3 and 4 and the processing device 5 are substantially parallel to the front-back or left-right directions.

[0037] Robot 1 includes: two hands 6 and 7, which mount a base plate 2 and are capable of moving horizontally; an arm 8 connected to the hand 6; an arm 9 connected to the hand 7; a main body 10 rotatably connected to the arms 8 and 9; a base 11 rotatably connected to the main body 10; and a base 12 that holds the base 11 in a manner capable of linear movement in the horizontal direction. The main body 10 includes: an arm support 15 that supports the base ends of the arms 8 and 9 and is capable of lifting; a support frame 16 that supports the arm support 15 so that it is capable of lifting; and a rotating frame 17 that constitutes the lower part of the main body 10.

[0038] Hand 6 is rotatably connected to the front end of arm 8 along a vertical axis, and hand 7 is rotatably connected to the front end of arm 9 along a vertical axis. Hand 7 is positioned lower than hand 6. Arm 8 is positioned higher than hand 6. Arm 9 is positioned lower than hand 7. The base ends of arms 8 and 9 are rotatably connected to the main body 10 along a vertical axis. Specifically, the base ends of arms 8 and 9 are rotatably connected to arm support 15. When viewed from above, the rotation center of arm 8 relative to the main body 10 coincides with the rotation center of arm 9 relative to the main body 10.

[0039] Hands 6 and 7 include: a hand base 18 rotatably connected to the front end of arms 8 and 9; and a plurality of linear forks 19, the upper surface of which is provided for mounting a substrate 2. In this embodiment, hands 6 and 7 have four forks 19. The four forks 19 protrude from the hand base 18 in the same horizontal direction. Furthermore, the four forks 19 are arranged parallel to each other. The forks 19 of hand 6 and hand 7 protrude in the same direction.

[0040] Arms 8 and 9 are multi-joint arms that extend and retract horizontally. Arms 8 and 9 are composed of a first arm portion 21 and a second arm portion 22 that are rotatably connected to each other. That is, arms 8 and 9 are composed of two arms that are rotatably connected to each other and can extend and retract horizontally. The base end of the first arm portion 21 is rotatably connected to the main body portion 10 (specifically, the arm support member 15). The base end of the second arm portion 22 is rotatably connected to the front end of the first arm portion 21. Hands 6 and 7 are rotatably connected to the front end of the second arm portion 22. In arm 8, the second arm portion 22 is positioned lower than the first arm portion 21, and in arm 9, the second arm portion 22 is positioned higher than the first arm portion 21.

[0041] The base end of arm 8 is rotatably connected to the upper end of arm support 15, and the base end of arm 9 is rotatably connected to the lower end of arm support 15. In the horizontal direction, the distance between the rotation center of the first arm portion 21 relative to arm support 15 and the rotation center of the second arm portion 22 relative to the first arm portion 21, and the distance between the rotation center of the second arm portion 22 relative to the first arm portion 21 and the rotation center of hands 6 and 7 relative to the second arm portion 22 are equal.

[0042] Arms 8 and 9 can extend and retract horizontally between a position where arms 8 and 9 extend so that the tips of hands 6 and 7 (i.e., the tips of forks 19) move away from the main body 10 and a position where arms 8 and 9 retract so that the tips of hands 6 and 7 approach the main body 10. When the extension and retraction of arms 8 and 9 relative to the main body 10 are equal, hands 6 and 7 overlap vertically, and arms 8 and 9 overlap vertically.

[0043] The support frame 16 holds the hands 6 and 7 and the arms 8 and 9 in a height-adjustable manner via the arm support member 15. The support frame 16 includes: a columnar first support frame 23 that holds the arm support member 15 in a height-adjustable manner; and a columnar second support frame 24 that holds the first support frame 23 in a height-adjustable manner. The rotating frame 17 is formed as a thin, flat, generally rectangular parallelepiped in the vertical direction. Furthermore, the rotating frame 17 is formed as an elongated, generally rectangular parallelepiped. The lower end of the second support frame 24 is fixed to the upper surface of the front end side of the rotating frame 17. The base end side of the rotating frame 17 is rotatably connected to the base 11 along an axis of rotation in the vertical direction. The rotating frame 17 is positioned higher than the base 11. The base 11 is capable of linear movement relative to the base 12 in the left-right direction.

[0044] In addition, robot 1 includes: an arm drive mechanism 27 for extending and retracting arm 8; an arm drive mechanism 28 for extending and retracting arm 9; a rotation mechanism 29 for rotating main body 10; a lifting mechanism 30 for raising and lowering hands 6 and 7 and arms 8 and 9; a horizontal movement mechanism 31 for moving main body 10 and base 11 together in the left-right direction; and a control unit 32 for controlling robot 1. Robot 1 transports substrate 2 by a combination of the extension and retraction of arms 8 and 9, the raising and lowering of arms 8 and 9, the rotation of main body 10, and the horizontal movement.

[0045] Furthermore, robot 1 has two detection mechanisms 33 and one detection mechanism 34 for detecting the position of substrate 2 mounted on hand 6, and two detection mechanisms 33 and one detection mechanism 34 for detecting the position of substrate 2 mounted on hand 7. That is, robot 1 has four detection mechanisms 33 and two detection mechanisms 34. In this embodiment, detection mechanism 33 is the first detection mechanism, and detection mechanism 34 is the second detection mechanism.

[0046] The arm drive mechanism 27 includes: an electric motor as a drive source; a power transmission mechanism that transmits the power of the electric motor to the arm 8 and the hand 6; and an encoder for detecting the rotation amount of the electric motor. The electric motor is a servo motor, and is controlled based on the detection result of the encoder. The arm drive mechanism 27 extends and retracts the arm 8 in the horizontal direction, so that the hand 6 moves linearly relative to the main body 10 in a certain direction. The arm drive mechanism 27 is electrically connected to the control unit 32. Specifically, the electric motor and encoder of the arm drive mechanism 27 are electrically connected to the control unit 32.

[0047] Like arm drive mechanism 27, arm drive mechanism 28 includes: an electric motor as a drive source; a power transmission mechanism that transmits the power of the electric motor to arm 9 and hand 7; and an encoder for detecting the rotation amount of the electric motor. The electric motor is a servo motor, controlled according to the detection result of the encoder. Arm drive mechanism 28 extends and retracts arm 9 in the horizontal direction, so that hand 7 moves linearly relative to main body 10 in a certain direction. Arm drive mechanism 28 is electrically connected to control unit 32. Specifically, the electric motor and encoder of arm drive mechanism 28 are electrically connected to control unit 32.

[0048] The rotation mechanism 29 uses the vertical direction as the axis of rotation, causing the rotating frame 17 to rotate relative to the base 11. That is, the rotation mechanism 29 uses the vertical direction as the axis of rotation, causing the arms 8 and 9 to rotate together with the main body 10. The rotation mechanism 29 includes: a motor as a drive source; a power transmission mechanism for transmitting the power of the motor to the rotating frame 17; and an encoder for detecting the rotation amount of the motor. The motor is a servo motor, and control is performed based on the encoder's detection results. The rotation mechanism 29 is electrically connected to the control unit 32. Specifically, the motor and encoder of the rotation mechanism 29 are electrically connected to the control unit 32.

[0049] The lifting mechanism 30 raises and lowers the first support frame 23 relative to the second support frame 24, and raises and lowers the arm support member 15 relative to the first support frame 23. The lifting mechanism 30 includes: an electric motor for raising and lowering the arm support member 15 and the first support frame 23; a reducer for transmitting power from the electric motor to the first support frame 23 and the arm support member 15; and an encoder for detecting the rotational amount of the electric motor. The electric motor is a servo motor, controlled according to the encoder's detection results.

[0050] The lifting mechanism 30 is electrically connected to the control unit 32. Specifically, the motor and encoder of the lifting mechanism 30 are electrically connected to the control unit 32. Alternatively, the robot 1 may also have separate lifting mechanisms for raising and lowering the arm support 15 relative to the first support frame 23 and for raising and lowering the first support frame 23 relative to the second support frame 24.

[0051] The horizontal movement mechanism 31 causes the base 11 to move linearly in the left-right direction relative to the base 12. That is, the horizontal movement mechanism 31 causes the main body 10 and arms 8 and 9 to move linearly in the left-right direction together with the base 11. The horizontal movement mechanism 31 includes a motor as a drive source, a power transmission mechanism for transmitting power from the motor to the base 11, and an encoder for detecting the rotational amount of the motor. The motor is a servo motor, and control is performed based on the encoder's detection results. The horizontal movement mechanism 31 is electrically connected to the control unit 32. Specifically, the motor and encoder of the horizontal movement mechanism 31 are electrically connected to the control unit 32.

[0052] The detection mechanism 33 is an optical detection mechanism. Alternatively, the detection mechanism 33 is a reflective detection mechanism having a light-emitting part 37 and a light-receiving part 38 that receives light emitted from the light-emitting part 37 and reflected by the substrate 2. The detection mechanisms 33 are respectively mounted on hands 6 and 7. Specifically, two detection mechanisms 33 are mounted on hand 6 and two detection mechanisms 33 are mounted on hand 7. The detection mechanisms 33 are electrically connected to the control unit 32. In this embodiment, the light-emitting part 37 is a first light-emitting part, and the light-receiving part 38 is a first light-receiving part.

[0053] The detection mechanism 33 is mounted on the hands 6 and 7 with the light-emitting surface of the light-emitting part 37 and the light-receiving surface of the light-receiving part 38 facing upwards. Additionally, the detection mechanism 33 is mounted on the upper surface of the fork portion 19. In this embodiment, the detection mechanism 33 is mounted on the two inner forks 19 of the four forks 19 in each of the hands 6 and 7, arranged in a direction orthogonal to the long side direction of the fork portion 19. Furthermore, the detection mechanism 33 is mounted on the front end of the fork portion 19.

[0054] Two detection mechanisms 33, respectively mounted on hands 6 and 7, are positioned at the same location along the long side of the fork 19. Furthermore, the two detection mechanisms 33 mounted on hands 6 and 7 are arranged at a distance from each other in a direction orthogonal to the long side of the fork 19. Alternatively, the detection mechanism 33 may be mounted on the two outermost forks 19 of the four forks 19 in each of hands 6 and 7, positioned orthogonal to the long side of the fork 19. Additionally, the detection mechanism 33 may be mounted on the base end side of the fork 19.

[0055] The detection mechanism 34 is an optical detection mechanism. Alternatively, the detection mechanism 34 is a transmissive detection mechanism having a light-emitting part 39 and a light-receiving part 40 arranged opposite to the light-emitting part 2. The light-emitting part 39 is arranged opposite to the light-receiving part 40 at a predetermined interval in the vertical direction. In this embodiment, the light-receiving part 40 is a line sensor. In the light-receiving part 40, multiple light-receiving elements are arranged in a row. The detection mechanism 34 is electrically connected to the control unit 32. In this embodiment, the light-emitting part 39 is a second light-emitting part, and the light-receiving part 40 is a second light-receiving part.

[0056] The detection mechanism 34 is mounted on the main body 10. Specifically, the detection mechanism 34 is fixed to the sensor fixing member 42, which is fixed to the arm support member 15, and the detection mechanism 34 is fixed to the arm support member 15 via the sensor fixing member 42. In this embodiment, the detection mechanism 34 for detecting the position of the substrate 2 mounted on the hand 6 and the detection mechanism 34 for detecting the position of the substrate 2 mounted on the hand 7 are fixed to the arm support member 15 via the sensor fixing member 42. That is, two detection mechanisms 34 are fixed to the arm support member 15. The two detection mechanisms 34 overlap in the vertical direction.

[0057] The detection mechanism 34 rotates together with the arm support 15 and rises and falls together with the arm support 15. As described above, in the light-receiving section 40, a plurality of light-receiving elements are arranged in a row. Specifically, when the long side direction of the fork 19 is aligned with the front-back direction, in the light-receiving section 40, a plurality of light-receiving elements are arranged in a row in the left-right direction; when the long side direction of the fork 19 is aligned with the left-right direction, in the light-receiving section 40, a plurality of light-receiving elements are arranged in a row in the front-back direction.

[0058] As described above, robot 1 transports substrate 2 from storage boxes 3 and 4 to processing device 5. Furthermore, as described above, arms 8 and 9 are horizontally extendable between a position where arms 8 and 9 extend so that the tips of hands 6 and 7 are away from the main body 10 and a position where arms 8 and 9 retract so that the tips of hands 6 and 7 are close to the main body 10. In this embodiment, when robot 1 receives substrate 2 from storage boxes 3 and 4, and when robot 1 transfers substrate 2 to processing device 5, arms 8 and 9 extend, so that the tips of hands 6 and 7 move away from the main body 10.

[0059] The position of the hand 6 when the front end of the hand 6 is moved away from the main body 10 (i.e., the arm 8 is extended), the base plate 2 placed in the storage box 3 is loaded onto the hand 6 and received. Figure 1 If the position shown is designated as hand position 6A, and the position of hand 6 when the front end of hand 6 is moved away from the main body 10 (i.e., the arm 8 is extended) and the substrate 2 loaded on hand 6 is handed over to the processing device 5 is designated as hand position 6B, then robot 1 performs the following actions: the action of moving hand 6 to hand position 6A with the front end of hand 6 away from the main body 10, i.e., action M11; the action of moving hand 6, which receives substrate 2 at hand position 6A, with the front end of hand 6 approaching the main body 10 after action M11, i.e., action M12; and the action of moving hand 6, which is loaded with substrate 2, to hand position 6B with the front end of hand 6 away from the main body 10 after action M12, i.e., action M13. In actions M11 and M13, the retracted arm 8 is extended, and in action M12, the extended arm 8 is retracted.

[0060] Additionally, the position of the hand 6 when the base plate 2 placed in the storage box 4 is mounted on the hand 6 and received while the front end of the hand 6 is moved away from the main body 10 is also in this position. Figure 2If the position shown is designated as hand position 6C, then robot 1 performs the following actions: Action M14, where the hand 6 moves to hand position 6C with its tip moving away from the main body 10; Action M15, where, after action M14, the hand 6 receiving the substrate 2 at hand position 6C moves with its tip approaching the main body 10; and Action M16, where, after action M15, the hand 6 carrying the substrate 2 moves to hand position 6B with its tip moving away from the main body 10. In actions M14 and M16, the retracted arm 8 extends; in action M15, the extended arm 8 retracts.

[0061] Similarly, when the hand 7 is in a state where its tip moves away from the main body 10 (i.e., the arm 9 is extended), the position of the hand 7 when it loads the substrate 2 placed in the storage box 3 onto the hand 7 and receives it is designated as hand position 7A. When the hand 7 is in a state where its tip moves away from the main body 10 (i.e., the arm 9 is extended), the position of the hand 7 when it hands over the substrate 2 loaded on the hand 7 to the processing device 5 is designated as hand position 7B. Then, the robot 1 performs the following actions: the action of moving the hand 7 to hand position 7A with its tip moving away from the main body 10 is action M21; after action M21, the action of moving the hand 7 receiving the substrate 2 at hand position 7A with its tip approaching the main body 10 is action M22; after action M22, the action of moving the hand 7 loaded with the substrate 2 to hand position 7B with its tip moving away from the main body 10 is action M23. In actions M21 and M23, the retracted arm 9 extends; in action M22, the extended arm 9 retracts.

[0062] Furthermore, if the position of the hand 7 when it is loading the substrate 2 placed in the storage box 4 onto the hand 7 and receiving it while the front end of the hand 7 is moving away from the main body 10 is defined as hand position 7C, then the robot 1 performs the following actions: the action of moving the hand 7 to hand position 7C with the front end of the hand 7 moving away from the main body 10, namely action M24; the action of moving the hand 7 receiving the substrate 2 at hand position 7C with the front end of the hand 7 approaching the main body 10 after action M24, namely action M25; and the action of moving the hand 7 loaded with the substrate 2 to hand position 7B with the front end of the hand 7 moving away from the main body 10 after action M25, namely action M26. In actions M24 and M26, the retracted arm 9 extends, and in action M25, the extended arm 9 retracts.

[0063] When actions M12 and M15 are completed, the rotation radius (turning radius) of the main body 10, including the substrate 2 mounted on the hand 6, the hand 6, and the arm 8, is at its minimum. Similarly, when actions M22 and M25 are completed, the rotation radius of the main body 10, including the substrate 2 mounted on the hand 7, the hand 7, and the arm 9, is at its minimum.

[0064] As described above, the arm drive mechanism 27 extends and retracts the arm 8 by causing the hand 6 to move linearly relative to the main body 10 in a certain direction, and the arm drive mechanism 28 extends and retracts the arm 9 by causing the hand 7 to move linearly relative to the main body 10 in a certain direction. That is, when the robot 1 performs actions M11 to M16, the hand 6 moves linearly relative to the main body 10 in a certain direction, and the hand 7 moves linearly relative to the main body 10 in a certain direction when the robot 1 performs actions M21 to M26.

[0065] In this embodiment, the storage box 3 is positioned at the front of the robot 1, the storage box 4 is positioned at the right side of the robot 1, and the processing device 5 is positioned at the rear of the robot 1. Therefore, when the robot 1 performs actions M11-M13 and M16, the hand 6 moves linearly relative to the main body 10 in the front-back direction, and when the robot 1 performs actions M14 and M15, it moves linearly relative to the main body 10 in the left-right direction. Similarly, when the robot 1 performs actions M21-M23 and M26, the hand 7 moves linearly relative to the main body 10 in the front-back direction, and when the robot 1 performs actions M24 and M25, it moves linearly relative to the main body 10 in the left-right direction.

[0066] Specifically, when robot 1 performs action M11, hand 6 moves forward in a straight line relative to the main body 10 with the front end of fork 19 facing forward; when robot 1 performs action M12, it moves backward in a straight line relative to the main body 10 with the front end of fork 19 facing forward; when robot 1 performs action M14, it moves to the right relative to the main body 10 with the front end of fork 19 facing right; when robot 1 performs action M15, it moves to the left relative to the main body 10 with the front end of fork 19 facing right; and when robot 1 performs actions M13 and M16, it moves backward in a straight line relative to the main body 10 with the front end of fork 19 facing backward.

[0067] Similarly, when robot 1 performs action M21, hand 7 moves forward in a straight line relative to the main body 10 with the front end of fork 19 facing forward; when robot 1 performs action M22, it moves backward in a straight line relative to the main body 10 with the front end of fork 19 facing forward; when robot 1 performs action M24, it moves to the right relative to the main body 10 with the front end of fork 19 facing right; when robot 1 performs action M25, it moves to the left relative to the main body 10 with the front end of fork 19 facing right; and when robot 1 performs actions M23 and M26, it moves backward in a straight line relative to the main body 10 with the front end of fork 19 facing backward.

[0068] When robot 1 performs action M11, the two detection mechanisms 33 mounted on hand 6 pass through the underside of the base plate 2 placed on storage box 3 (specifically, after action M11, the underside of the base plate 2 mounted on hand 6). When robot 1 performs action M21, the two detection mechanisms 33 mounted on hand 7 pass through the underside of the base plate 2 placed on storage box 3 (specifically, after action M21, the underside of the base plate 2 mounted on hand 7).

[0069] When robot 1 performs action M14, the two detection mechanisms 33 mounted on hand 6 pass through the underside of the base plate 2 placed on storage box 4 (specifically, after action M14, the underside of the base plate 2 mounted on hand 6). When robot 1 performs action M24, the two detection mechanisms 33 mounted on hand 7 pass through the underside of the base plate 2 placed on storage box 4 (specifically, after action M24, the underside of the base plate 2 mounted on hand 7).

[0070] When robot 1 performs action M12, one end face of substrate 2 mounted on hand 6 passes between the light-emitting part 39 and the light-receiving part 40 of one of the two detection mechanisms 34 in the left-right direction. When robot 1 performs action M22, one end face of substrate 2 mounted on hand 7 passes between the light-emitting part 39 and the light-receiving part 40 of the other detection mechanism 34. In this embodiment, when robot 1 performs actions M12 and M22, the detection mechanism 34 is positioned to the right of hands 6 and 7, and the right end face of substrate 2 mounted on hands 6 and 7 passes between the light-emitting part 39 and the light-receiving part 40.

[0071] When robot 1 performs action M15, one end face of substrate 2 mounted on hand 6 in the front-rear direction passes between the light-emitting part 39 and the light-receiving part 40 of one of the two detection mechanisms 34. When robot 1 performs action M25, one end face of substrate 2 mounted on hand 7 in the front-rear direction passes between the light-emitting part 39 and the light-receiving part 40 of the other detection mechanism 34. In this embodiment, when robot 1 performs actions M15 and M25, the detection mechanism 34 is positioned rearward than hands 6 and 7, and the rear end face of substrate 2 mounted on hands 6 and 7 passes between the light-emitting part 39 and the light-receiving part 40.

[0072] Specifically, the detection mechanism 34 is positioned such that, when the robot 1 performs actions M12 and M22, the right end face of the substrate 2 mounted on the hands 6 and 7 passes between the light-emitting part 39 and the light-receiving part 40; and when the robot 1 performs actions M15 and M25, the rear end face of the substrate 2 mounted on the hands 6 and 7 passes between the light-emitting part 39 and the light-receiving part 40. Furthermore, the detection mechanism 34 is positioned rearward of the rear end face of the substrate 2 mounted on the hands 6 and 7 at hand positions 6A and 7A, and to the left of the left end face of the substrate 2 mounted on the hands 6 and 7 at hand positions 6C and 7C. Additionally, the detection mechanism 34 is positioned in the front-to-back direction between the front and rear end faces of the substrate 2 mounted on the hands 6 and 7 after actions M12 and M22 have ended, and in the left-to-right direction between the right and left end faces of the substrate 2 mounted on the hands 6 and 7 after actions M15 and M25 have ended.

[0073] As described above, since the light-receiving part 40 is a line sensor with multiple light-receiving elements arranged in a row, the position of the right end face of the substrate 2 mounted on the hands 6 and 7 after the actions M12 and M22 are completed can be detected by the detection mechanism 34 in the left-right direction. In addition, the position of the rear end face of the substrate 2 mounted on the hands 6 and 7 after the actions M15 and M25 are completed can be detected by the detection mechanism 34 in the front-back direction.

[0074] Additionally, robot 1 rotates the main body 10 between actions M12 and M13, and between actions M15 and M16. During this time, arm 9 also retracts. Furthermore, robot 1 rotates the main body 10 between actions M22 and M23, and between actions M25 and M26. During this time, arm 8 also retracts. Additionally, as needed, robot 1 performs lifting and lowering of the arm support 15 and left-right movement of the main body 10 between actions M12 and M13, between actions M15 and M16, between actions M22 and M23, and between actions M25 and M26. Furthermore, as needed, robot 1 sometimes performs lifting and lowering of the arm support 15 and left-right movement of the main body 10 during actions M11-M16 and M21-M26.

[0075] (Robot control methods)

[0076] When the robot 1 performs action M11, the control unit 32 acquires position data D1 and position data D2. Position data D1 is the position data of the hand 6 in the front-back direction when one of the two detection mechanisms 33 mounted on the hand 6 detects the substrate 2 (specifically, when one detection mechanism 33 detects the rear end face of the substrate 2 placed in the storage box 3 (i.e., when one detection mechanism 33 initially detects the substrate 2)). Position data D2 is the position data of the hand 6 in the front-back direction when the other detection mechanism 33 detects the substrate 2 (specifically, when the other detection mechanism 33 detects the rear end face of the substrate 2 placed in the storage box 3 (i.e., when the other detection mechanism 33 initially detects the substrate 2)). The control unit 32 acquires position data D1 and D2 based on the detection results of the detection mechanisms 33 and the encoder detection results of the arm drive mechanism 27.

[0077] Based on position data D1 and D2, the control unit 32 determines the position and orientation (tilt of the substrate 2 in the horizontal plane) of the substrate 2 placed on the storage box 3 in the front-back direction. Furthermore, the control unit 32 compares the determined position and orientation of the substrate 2 in the front-back direction with the position and orientation of the substrate 2 in the front-back direction previously taught to the robot 1, and, based on the comparison result, corrects the position and orientation of the hand 6 in the front-back direction when it reaches the hand position 6A during robot 1's action M11. In other words, when robot 1 performs action M11, the control unit 32 corrects the position and orientation of the hand 6 in the front-back direction when it reaches the hand position 6A based on position data D1 and D2.

[0078] Specifically, when the robot 1 performs action M11, the control unit 32 controls the arm drive mechanism 27, the rotation mechanism 29, and the horizontal movement mechanism 31 based on position data D1 and D2, and corrects the position and orientation of the hand 6 in the front-back direction when it reaches hand position 6A. Furthermore, when the robot 1 performs action M11, the control unit 32 corrects the position and orientation of the hand 6 in the front-back direction based on position data D1 and D2, so that the position of the substrate 2 mounted on the hand 6 in the front-back direction is appropriate, and the orientation of the substrate 2 mounted on the hand 6 is appropriate.

[0079] Furthermore, when the robot 1 performs action M12, the control unit 32 acquires position data D3, which is the position data of the right end face of the substrate 2 in the left-right direction detected by the detection mechanism 34 when the hand 6 moves to the predetermined measurement position. The control unit 32 acquires the position data D3 based on the detection results of the detection mechanism 34 and the detection results of the encoder of the arm drive mechanism 27. In this embodiment, for example, the position of the hand 6 at the end of action M12 is taken as the measurement position, but it is also possible that the predetermined position of the hand 6 during action M12 is taken as the measurement position.

[0080] The control unit 32 determines the position of the substrate 2 mounted on the hand 6 in the left-right direction based on the position data D3. Furthermore, the control unit 32 compares the determined position of the substrate 2 in the left-right direction with the position of the substrate 2 in the left-right direction previously taught to the robot 1, and, based on the comparison result, corrects the position of the hand 6 in the left-right direction when it reaches the hand position 6B during the robot 1's action M13. In other words, the control unit 32 corrects the position of the hand 6 in the left-right direction when it reaches the hand position 6B based on the position data D3 during the robot 1's action M13.

[0081] Specifically, when the robot 1 performs action M13, the control unit 32 controls the horizontal movement mechanism 31 based on the position data D3 to correct the position of the hand 6 in the left-right direction when it reaches the hand position 6B. Furthermore, when the robot 1 performs action M13, the control unit 32 corrects the position of the hand 6 in the left-right direction based on the position data D3 to ensure that the position of the substrate 2 placed on the processing device 5 in the left-right direction is appropriate.

[0082] Similarly, when the robot 1 performs action M21, the control unit 32 acquires position data D4 and position data D5. Position data D4 is the position data of the hand 7 in the forward-backward direction when one of the two detection mechanisms 33 mounted on the hand 7 detects the substrate 2, and position data D5 is the position data of the hand 7 in the forward-backward direction when the other detection mechanism 33 detects the substrate 2. The control unit 32 acquires position data D4 and D5 based on the detection results of the detection mechanisms 33 and the encoder detection results of the arm drive mechanism 28.

[0083] The control unit 32 determines the position and orientation of the substrate 2 placed on the storage box 3 in the front-back direction based on the position data D4 and D5. In addition, the control unit 32 compares the determined position and orientation of the substrate 2 in the front-back direction with the position and orientation of the substrate 2 in the front-back direction that have been taught to the robot 1 in advance, and when the robot 1 performs action M21, it corrects the position and orientation of the hand 7 in the front-back direction when it reaches the hand position 7A based on the comparison result.

[0084] Specifically, when the robot 1 performs action M21, the control unit 32 controls the arm drive mechanism 28, the rotation mechanism 29, and the horizontal movement mechanism 31 based on position data D4 and D5 to correct the position and orientation of the hand 7 in the front-back direction when it reaches hand position 7A. Furthermore, when the robot 1 performs action M21, the control unit 32 corrects the position and orientation of the hand 7 in the front-back direction based on position data D4 and D5 to ensure that the position of the substrate 2 mounted on the hand 7 in the front-back direction is appropriate, and that the orientation of the substrate 2 mounted on the hand 7 is appropriate.

[0085] Additionally, when the robot 1 performs action M22, the control unit 32 acquires position data D6, which is the position data of the right end face of the substrate 2 in the left-right direction detected by the detection mechanism 34 when the hand 7 moves to the predetermined measurement position. The control unit 32 acquires position data D6 based on the detection results of the detection mechanism 34 and the encoder detection results of the arm drive mechanism 28. In this embodiment, for example, the position of the hand 7 at the end of action M22 is taken as the measurement position, but it is also possible that the predetermined position of the hand 7 during action M22 is taken as the measurement position.

[0086] Based on position data D6, the control unit 32 determines the position of the substrate 2 mounted on the hand 7 in the left-right direction. Furthermore, the control unit 32 compares the determined position of the substrate 2 in the left-right direction with the position of the substrate 2 in the left-right direction previously taught to the robot 1, and, based on this comparison result, corrects the position of the hand 7 in the left-right direction when it reaches hand position 7B while the robot 1 performs action M23. In other words, the control unit 32 corrects the position of the hand 7 in the left-right direction when it reaches hand position 7B based on position data D6 while the robot 1 performs action M23.

[0087] Specifically, when the robot 1 performs action M23, the control unit 32 controls the horizontal movement mechanism 31 based on the position data D6 to correct the position of the hand 7 in the left-right direction when it reaches the hand position 7B. Furthermore, when the robot 1 performs action M23, the control unit 32 corrects the position of the hand 7 in the left-right direction based on the position data D6 to ensure that the position of the substrate 2 placed on the processing device 5 in the left-right direction is appropriate.

[0088] In addition, when the robot 1 performs action M14, the control unit 32 acquires position data D11 and position data D12. The position data D11 is the position data of the hand 6 in the left-right direction when one of the two detection mechanisms 33 mounted on the hand 6 detects the substrate 2 (specifically, when one detection mechanism 33 detects the left end face of the substrate 2 placed on the storage box 4). The position data D12 is the position data of the hand 6 in the left-right direction when the other detection mechanism 33 detects the substrate 2 (specifically, when the other detection mechanism 33 detects the left end face of the substrate 2 placed on the storage box 4). When the robot 1 performs action M15, the control unit 32 acquires position data D13, which is the position data of the rear end face of the substrate 2 in the front-back direction detected by the detection mechanism 34 when the hand 6 moves to the specified measurement position.

[0089] In this embodiment, for example, the position of hand 6 at the end of action M15 is used as the measurement position, but it can also be a predetermined position of hand 6 during action M15. Furthermore, the control unit 32 acquires position data D11 and D12 based on the detection results of the detection mechanism 33 and the encoder of the arm drive mechanism 27, and acquires position data D13 based on the detection results of the detection mechanism 34 and the encoder of the arm drive mechanism 27. Additionally, after robot 1 performs action M14, when the base plate 2 placed in the storage box 4 is loaded onto hand 6, arm 8 extends to position hand 6 in the pre-taught hand position 6C. The base plate 2 is mounted on hand 6 to maintain its position (position and orientation) on the storage box 4.

[0090] Based on position data D11 to D13, the control unit 32 determines the position of the substrate 2 mounted on the hand 6 in the front-back direction, the position in the left-right direction, and its orientation. Furthermore, the control unit 32 compares the determined position (horizontal position) and orientation of the substrate 2 in the front-back and left-right directions with the horizontal position and orientation of the substrate 2 pre-taught to the robot 1. When the robot 1 performs action M16, based on this comparison result, the control unit 32 corrects the horizontal position and orientation of the hand 6 when it reaches hand position 6B. In other words, when the robot 1 performs action M16, the control unit 32 corrects the horizontal position and orientation of the hand 6 when it reaches hand position 6B based on position data D11 to D13.

[0091] Specifically, when the robot 1 performs action M16, the control unit 32 controls the arm drive mechanism 27, the rotation mechanism 29, and the horizontal movement mechanism 31 based on position data D11-D13, and corrects the horizontal position and orientation of the hand 6 when it reaches hand position 6B. Furthermore, when the robot 1 performs action M16, the control unit 32 corrects the horizontal position and orientation of the hand 6 when it reaches hand position 6B based on position data D11-D13, so that the position of the substrate 2 placed on the processing device 5 in the horizontal direction is appropriate, and the orientation of the substrate 2 placed on the processing device 5 is appropriate.

[0092] Similarly, when the robot 1 performs action M24, the control unit 32 acquires position data D14 and position data D15. Position data D14 is the position data of the hand 7 in the left-right direction when one of the two detection mechanisms 33 installed on the hand 7 detects the substrate 2. Position data D15 is the position data of the hand 7 in the left-right direction when the other detection mechanism 33 detects the substrate 2. When the robot 1 performs action M25, the control unit 32 acquires position data D16. Position data D16 is the position data of the rear end face of the substrate 2 in the front-back direction detected by the detection mechanism 34 when the hand 7 moves to the specified measurement position.

[0093] In this embodiment, for example, the position of hand 7 at the end of action M25 is used as the measurement position, but it can also be a predetermined position of hand 7 during action M25. Furthermore, the control unit 32 acquires position data D14 and D15 based on the detection results of the detection mechanism 33 and the encoder of the arm drive mechanism 28, and acquires position data D16 based on the detection results of the detection mechanism 34 and the encoder of the arm drive mechanism 28. Additionally, after robot 1 performs action M24, when the base plate 2 placed in the storage box 4 is loaded onto hand 7, the arm 9 extends so that hand 7 is positioned in the pre-taught hand position 7C. The base plate 2 is loaded onto hand 7 to maintain its position (position and orientation) on the storage box 4.

[0094] Based on position data D14-D16, the control unit 32 determines the position of the substrate 2 mounted on the hand 7 in the front-back direction, the position in the left-right direction, and its orientation. Furthermore, the control unit 32 compares the determined position (horizontal position) and orientation of the substrate 2 in the front-back and left-right directions with the horizontal position and orientation of the substrate 2 pre-taught to the robot 1. When the robot 1 performs action M26, based on this comparison result, the control unit 32 corrects the horizontal position and orientation of the hand 7 when it reaches hand position 7B. In other words, when the robot 1 performs action M26, the control unit 32 corrects the horizontal position and orientation of the hand 7 when it reaches hand position 7B based on position data D14-D16.

[0095] Specifically, when the robot 1 performs action M26, the control unit 32 controls the arm drive mechanism 28, the rotation mechanism 29, and the horizontal movement mechanism 31 based on position data D14-D16 to correct the horizontal position and orientation of the hand 7 when it reaches hand position 7B. Furthermore, when the robot 1 performs action M26, the control unit 32 corrects the horizontal position and orientation of the hand 7 when it reaches hand position 7B based on position data D14-D16, so that the horizontal position of the substrate 2 placed on the processing device 5 is appropriate, and the orientation of the substrate 2 placed on the processing device 5 is appropriate.

[0096] In this embodiment, the storage box 4 is the receiving part, the processing device 5 is the hand-transfer part, hand positions 6C and 7C are receiving positions, and hand positions 6B and 7B are hand-transfer positions. Furthermore, actions M14 and M24 are first actions, actions M15 and M25 are second actions, and actions M16 and M26 are third actions. In this embodiment, the left-right direction (Y-direction) is the direction of movement of hands 6 and 7 when the robot 1 performs actions M14 and M24 as the first actions, i.e., the first direction, and the front-back direction (X-direction) is the second direction orthogonal to the up-down direction and the first direction. When the robot 1 performs actions M14, M15, M24, and M25, the two detection mechanisms 33 mounted on hand 6 and the two detection mechanisms 33 mounted on hand 7 are arranged at intervals in the front-back direction.

[0097] (Method for calculating the correction value for the hand)

[0098] Figure 5 It is used to explain in Figure 1 The diagram shows the calculation method for the correction values ​​of the horizontal position and orientation of hands 6 and 7 when robot 1 performs actions M16 and M26.

[0099] For example, in storage box 4, such as Figure 5 When the substrate 2 is placed as shown by the solid line, the correction values ​​for the positions and orientations of the hands 6 and 7 in the front-back direction, left-right direction, and direction are calculated as follows when the robot 1 performs actions M16 and M26. Additionally, in Figure 5 In the diagram, the substrate 2, indicated by dashed lines, is the substrate 2 placed in its proper position within the storage box 4 (i.e., the substrate 2 placed in a manner that does not require correction of its horizontal position and orientation). Hereinafter, distinctions will be made... Figure 5 In the case of substrate 2 shown by the solid line and substrate 2 shown by the dashed line, the substrate 2 shown by the solid line is designated as substrate 2A, and the substrate 2 shown by the dashed line is designated as substrate 2B. In addition, the center of substrate 2B when viewed from the top and bottom is set as the origin OR.

[0100] When robot 1 performs actions M14 and M24, the position of the left end face of substrate 2B detected by one of the two detection mechanisms 33 installed on hands 6 and 7 is set as PB1, and the position of the left end face of substrate 2B detected by the other detection mechanism 33 installed on hands 6 and 7 is set as PB2. When robot 1 performs actions M15 and M25, the position of the rear end face of substrate 2B detected by detection mechanism 34 is set as PB3. Then, in the coordinate system with the origin OR as the origin, the coordinates of PB1 to PB3 are as follows.

[0101] PB1(-b3 / 2, -YB / 2)

[0102] PB2(b3 / 2, -YB / 2)

[0103] PB3(-XB / 2, b4-YB / 2)

[0104] Here, XB is the width of substrate 2 in the front-back direction, and YB is the width of substrate 2 in the left-right direction. Additionally, b3 is the front-back distance between PB1 and PB2 (i.e., the front-back distance between the two detection mechanisms 33), and the front-back distance between the origin OR and PB1 is equal to the front-back distance between the origin OR and PB2. Furthermore, b4 is the left-right distance between the left end face of substrate 2 and PB3.

[0105] Furthermore, if when robot 1 performs actions M14 and M24, the position of the left end face of substrate 2A detected by one of the two detection mechanisms 33 mounted on hands 6 and 7 is set as P1, and the position of the left end face of substrate 2A detected by the other detection mechanism 33 mounted on hands 6 and 7 is set as P2, and when robot 1 performs actions M15 and M25, the position of the rear end face of substrate 2A detected by detection mechanism 34 is set as P3, then in the coordinate system with the origin OR as the origin, the coordinates of P1 to P3 are as follows.

[0106] P1(-b3 / 2,-YB / 2+S1)

[0107] P2(b3 / 2,-YB / 2+S2)

[0108] P3(-XB / 2-S3,b4-YB / 2)

[0109] Here, S1 is the distance between PB1 and P1 in the left-right direction, S2 is the distance between PB2 and P2 in the left-right direction, and S3 is the distance between PB3 and P3 in the front-back direction.

[0110] If the position of the left rear corner of substrate 2B is set as the origin WOR, then the straight line passing through P1 and P2 in the coordinate system with origin WOR as the origin is shown below.

[0111] ax + by + c = 0

[0112] If the coordinates of P3 are set to (X0, Y0), then the distance L between the line and P3 is...

[0113] L=|aX0+bY0+c| / (a 2 +b 2 ) 1 / 2 .

[0114] Furthermore, if the position of substrate 2B corresponding to P3 of substrate 2A is set as P3′, then the coordinates of P3′ in a coordinate system with the origin OR as the origin are represented as follows.

[0115] P3′(-XB / 2,L-YB / 2)

[0116] If we define the tilt angle of substrate 2A relative to substrate 2B (i.e., the orientation shift of substrate 2A relative to substrate 2B) as θ, then

[0117] tanθ=(S2-S1) / b3,

[0118] Therefore, the angle θ, which is the correction value for the orientation of substrate 2A relative to substrate 2B, is calculated by the following formula.

[0119] θ=tanθ -1 ((S2-S1) / b3)

[0120] This angle θ becomes the correction value for the orientation of hands 6 and 7 when robot 1 performs actions M16 and M26.

[0121] In a coordinate system with the origin OR as the origin, if P3′ is an angle θ, the rotated position is set as P3′r, the coordinates of P3′r are set as (P3′rx, P3′ry), and the coordinates of P3′ are set as (P3′x, P3′y). Then P3′rx and P3′ry are expressed by the following formula.

[0122] P3′rx=P3′x×cosθ-P3′y×sinθ

[0123] P3′ry=P3′x×sinθ+P3′y×cosθ

[0124] In a coordinate system with the origin OR as the origin, if the coordinates of P3 are set as (P3x, P3y), then in order to calculate the parallel offset components ΔX and ΔY between P3 and P3′r, if the coordinates of P3 are represented as (P3xr, P3yr) and the coordinates of P3′r are represented as (P3′rxr, P3′ryr) in a coordinate system rotated by an angle θ around the origin OR, then as shown below.

[0125] P3′rxr=P3′rx×cosθ+P3′ry×sinθ

[0126] P3′ryr=-P3′rx×sinθ+P3′ry×cosθ

[0127] P3xr=P3x×cosθ+P3y×sinθ

[0128] P3yr=-P3x×sinθ+P3y×cosθ

[0129] Therefore, the parallel offset components ΔX and ΔY, which are the correction values ​​of substrate 2A relative to substrate 2B, are calculated by the following formulas.

[0130] ΔX=P3xr﹣P3′rxr

[0131] ΔY=P3yr﹣P3′ryr

[0132] The parallel offset component ΔX is the correction value of the position of hands 6 and 7 by the horizontal drive mechanism 31 when robot 1 performs actions M16 and M26. The parallel offset component ΔY is the correction value of the position of hands 6 and 7 by the arm drive mechanisms 27 and 28 when robot 1 performs actions M16 and M26.

[0133] When robot 1 performs actions M16 and M26, the angle θ is corrected by the rotation mechanism 29, the parallel offset component ΔX is corrected by the horizontal movement mechanism 31, and the parallel offset component ΔY is corrected by the arm drive mechanisms 27 and 28.

[0134] (Main effects of this implementation method)

[0135] As explained above, in this embodiment, when the robot 1 performs action M16, the control unit 32 corrects the position and orientation of the hand 6 in the horizontal direction when it reaches the hand position 6B based on the position data D11 to D13. When the robot 1 performs action M26, the control unit 32 corrects the position and orientation of the hand 7 in the horizontal direction when it reaches the hand position 7B based on the position data D14 to D16.

[0136] That is, in this embodiment, the control unit 32 only corrects the position and orientation of the hands 6 and 7 in the horizontal direction when the robot 1 performs actions M16 and M26, and does not correct the position and orientation of the hands 6 and 7 when performing actions M14 and M24. Therefore, in this embodiment, even if the substrate 2 placed in the storage box 4 can be placed in the processing device 5 after correcting the position and orientation of the substrate 2 in the horizontal direction, the transportation time of the substrate 2 from the storage box 4 to the processing device 5 can be shortened.

[0137] Furthermore, in this embodiment, since the main body 10 cannot be moved in the front-back direction, the orientation of the hands 6 and 7 cannot be properly corrected when the robot 1 performs actions M14 and M24. However, in this embodiment, even if the orientation of the hands 6 and 7 cannot be properly corrected when the robot 1 performs actions M14 and M24, the orientation of the hands 6 and 7 can be properly corrected when the robot 1 performs actions M16 and M26.

[0138] (Example of a change in robot control method)

[0139] In the above embodiment, the control unit 32 may also acquire position data D1 and D2 when the robot 1 performs action M11, acquire position data D3 when the robot 1 performs action M12, and correct the position and orientation of the hand 6 in the horizontal direction when it reaches hand position 6B based on position data D1 to D3 when the robot 1 performs action M13. In this case, after the robot 1 performs action M11, when the base plate 2 placed in the storage box 3 is loaded onto the hand 6, the arm 8 extends so that the hand 6 is positioned in the pre-taught hand position 6A. The base plate 2 is loaded onto the hand 6 to maintain its position (position and orientation) when placed on the storage box 3.

[0140] Furthermore, in this case, the control unit 32 determines the position and orientation of the substrate 2 mounted on the hand 6 in the front-back direction, the left-right direction, and the orientation based on the position data D1 to D3. It compares the determined position (horizontal position) and orientation of the substrate 2 in the front-back and left-right directions with the horizontal position and orientation of the substrate 2 pre-taught to the robot 1. When the robot 1 performs action M13, it corrects the horizontal position and orientation of the hand 6 when it reaches hand position 6B based on this comparison result. Specifically, when the robot 1 performs action M13, the control unit 32 controls the arm drive mechanism 27, the rotation mechanism 29, and the horizontal movement mechanism 31 based on the position data D1 to D3, correcting the horizontal position and orientation of the hand 6 when it reaches hand position 6B.

[0141] Similarly, in the above embodiment, the control unit 32 can also acquire position data D4 and D5 when the robot 1 performs action M21, acquire position data D6 when the robot 1 performs action M22, and correct the position and orientation of the hand 7 in the horizontal direction when it reaches hand position 7B based on position data D4 to D6 when the robot 1 performs action M23. In this case, after the robot 1 performs action M21, when the substrate 2 placed on the storage box 3 is loaded onto the hand 7, the arm 9 extends so that the hand 7 is positioned in the pre-taught hand position 7A. The substrate 2 is loaded onto the hand 7 to maintain its position (position and orientation) while placed on the storage box 3.

[0142] Furthermore, in this case, the control unit 32 determines the position of the substrate 2 mounted on the hand 7 in the front-back direction, the position and orientation in the left-right direction, and the orientation based on the position data D4 to D6. It compares the determined position (horizontal position) and orientation of the substrate 2 in the front-back and left-right directions with the horizontal position and orientation of the substrate 2 pre-taught to the robot 1. When the robot 1 performs action M23, it corrects the horizontal position and orientation of the hand 7 when it reaches hand position 7B based on this comparison result. Specifically, when the robot 1 performs action M23, the control unit 32 controls the arm drive mechanism 28, the rotation mechanism 29, and the horizontal movement mechanism 31 based on the position data D4 to D6 to correct the horizontal position and orientation of the hand 7 when it reaches hand position 7B.

[0143] In this modified example, the storage box 3 is the receiving part, and the hand positions 6A and 7A are the receiving positions. Furthermore, actions M11 and M21 are the first actions, actions M12 and M22 are the second actions, and actions M13 and M23 are the third actions. In this modified example, the forward / backward direction (X-direction) becomes the first direction of movement for hands 6 and 7 when robot 1 performs the first actions, namely actions M11 and M21, and the left / right direction (X-direction) becomes the second direction orthogonal to the up / down direction and the first direction. When robot 1 performs actions M11, M12, M21, and M22, the two detection mechanisms 33 mounted on hand 6 and the two detection mechanisms 33 mounted on hand 7 are arranged with a gap in the left / right direction.

[0144] In this modified example, even if the substrate 2 placed in the storage box 3 is placed in the processing device 5 after correcting the horizontal position and orientation of the substrate 2, the transport time of the substrate 2 from the storage box 3 to the processing device 5 can be shortened.

[0145] (Other implementation methods)

[0146] The above-described method and its variations are examples of preferred embodiments of the present invention, but are not limited thereto. Various modifications can be made without changing the spirit of the present invention.

[0147] In the above embodiment, robot 1 can also transport substrate 2 from processing device 5 to storage box 4. That is, robot 1 can also remove substrate 2 from processing device 5 and move substrate 2 from processing device 5 into storage box 4. In this case, processing device 5 becomes receiving unit and storage box 4 becomes transfer unit. Alternatively, in a modified example of the robot control method described above, robot 1 can also transport substrate 2 from processing device 5 to storage box 3. In this case, processing device 5 becomes receiving unit and storage box 3 becomes transfer unit.

[0148] In the above embodiment, the robot 1 may also have only one detection mechanism 34. In this case, the detection mechanism 34 is configured such that when the robot 1 performs action M12, the right end face of the substrate 2 mounted on the hand 6 passes between the light-emitting part 39 and the light-receiving part 40 of the detection mechanism 34, and when the robot 1 performs action M22, the right end face of the substrate 2 mounted on the hand 7 passes between the light-emitting part 39 and the light-receiving part 40 of the detection mechanism 34. Furthermore, the detection mechanism 34 is configured such that when the robot 1 performs action M15, the rear end face of the substrate 2 mounted on the hand 6 passes between the light-emitting part 39 and the light-receiving part 40 of the detection mechanism 34, and when the robot 1 performs action M25, the right end face of the substrate 2 mounted on the hand 7 passes between the light-emitting part 39 and the light-receiving part 40 of the detection mechanism 34.

[0149] In addition, in this case, when robot 1 performs actions M12 and M15, arm 9 extends or retracts when hand 7 is not loaded with substrate 2. When robot 1 performs actions M22 and M25, arm 8 extends or retracts when hand 6 is not loaded with substrate 2.

[0150] In the above embodiment, the light-receiving part 40 may also be a region sensor with multiple light-receiving elements arranged in two dimensions. Even in this case, the position of the right end face of the substrate 2 mounted on the hands 6 and 7 in the left-right direction can be detected by the detection mechanism 34, and the position of the rear end face of the substrate 2 mounted on the hands 6 and 7 in the front-back direction can also be detected by the detection mechanism 34.

[0151] In the above embodiments, arms 8 and 9 are arranged in a staggered manner in the vertical direction, but arms 8 and 9 can also be arranged at the same position in the vertical direction and adjacent to each other in the horizontal direction. Furthermore, in the above embodiments, the robot 1 may have only one hand and one arm. For example, the robot 1 may have only one hand 6 and one arm 8. Additionally, in the above embodiments, arms 8 and 9 may be composed of three or more arm segments.

[0152] In the above embodiments, robot 1, like the arm of an industrial robot disclosed in Japanese Patent Application Publication No. 2018-15839, may also have an arm consisting of two front-end arm portions rotatably connected to the front end side of the two hands 6 and 7 respectively, and a common arm portion rotatably connected to the base end side of the two front-end arm portions, in place of arms 8 and 9.

[0153] Furthermore, in the above embodiments, robot 1, like the arm of an industrial robot disclosed in Japanese Patent Application Publication No. 2019-25585, may also have an arm that maintains the slender, generally rectangular shape of hands 6 and 7, allowing hands 6 and 7 to move linearly back and forth in the horizontal direction, instead of arms 8 and 9. That is, robot 1 may also be a so-called linear robot in which hands 6 and 7 are connected to the arm in a manner that allows them to slide horizontally. In addition, in the above embodiments, the object to be transported by robot 1 may be an object other than the substrate 2.

Claims

1. An industrial robot for transporting objects shaped like rectangles or squares, characterized in that, include: A hand, which is used to load the object being transported and is capable of moving horizontally; Arm, which is connected to the hand; The main body is rotatably connected to the arm via an axis that rotates in the vertical direction; Two optical first detection mechanisms are mounted on the hand; An optical second detection mechanism is mounted on the main body. as well as The control unit controls the industrial robot. Furthermore, if the position of the hand when it is loading and receiving the transport object placed on the designated receiving portion while the front end of the hand is moving away from the main body is defined as the receiving position, then the position of the hand when it is transferring the transport object loaded on the hand to the designated handover portion while the front end of the hand is moving away from the main body is defined as the handover position. Then, a first action, a second action, and a third action are performed. The first action is the movement of the hand moving to the receiving position by moving the tip of the hand away from the main body. The second action is the movement of the hand, having received the object to be transported, moving to the receiving position by moving the tip of the hand closer to the main body after the first action. The third action is the movement of the hand, carrying the object to be transported, moving to the hand-over position by moving the tip of the hand away from the main body after the second action. When the industrial robot performs the first and second actions, the hand moves linearly relative to the main body in a certain direction. If the direction of hand movement when the industrial robot performs the first action and the second action is defined as the first direction, and the direction orthogonal to the first direction and the up-down direction is defined as the second direction, then... The first detection mechanism is a reflective detection mechanism comprising a first light-emitting part and a first light-receiving part. The first light-receiving part receives light emitted from the first light-emitting part and reflected by the object being transported. The two first detection units are configured with a gap between them in the second direction. The second detection mechanism is a transmissive detection mechanism having a second light-receiving part and a second light-emitting part. The second light-receiving part is composed of a line sensor or a region sensor, and the second light-emitting part is arranged opposite to the second light-receiving part at a predetermined interval in the vertical direction. When the industrial robot performs the first action, the two first detection mechanisms pass under the transported object placed in the receiving part. When the industrial robot performs the second action, one end face of the object being transported, mounted on the hand, passes between the second light-receiving part and the second light-emitting part in the second direction. When the industrial robot performs the first action, the control unit acquires first position data and second position data. The first position data is the position data of the hand in the first direction when one of the two first detection mechanisms detects the transported object. The second position data is the position data of the hand in the first direction when the other of the two first detection mechanisms detects the transported object. When the industrial robot performs the second action, the control unit acquires third position data. The third position data is the position data of one end face of the transported object in the second direction detected by the second detection mechanism when the hand moves to a predetermined measurement position. When the industrial robot performs the third action, the control unit corrects the position and orientation of the hand in the horizontal direction when it reaches the handover position based on the first position data, the second position data, and the third position data.

2. The industrial robot according to claim 1, characterized in that, The arm is composed of multiple arm sections that are rotatably connected to each other, and it can extend and retract in the horizontal direction. The hand is rotatably connected to the front end of the arm. The base end of the arm is rotatably connected to the main body.

3. The industrial robot according to claim 2, characterized in that, include: An arm drive mechanism that extends and retracts the arm by causing the hand to move linearly relative to the main body in a certain direction; A rotating mechanism that causes the main body to rotate; as well as A horizontal moving mechanism that causes the main body to move in a left-right direction orthogonal to the vertical direction. When the industrial robot performs the third action, the hand moves linearly relative to the main body in a forward-backward direction orthogonal to the up-down and left-right directions. When the industrial robot performs the third action, the control unit controls the arm drive mechanism, the rotation mechanism, and the horizontal movement mechanism based on the first position data, the second position data, and the third position data to correct the position and orientation of the hand in the horizontal direction when it reaches the handover position.

4. The industrial robot as described in claim 3, characterized in that, The first direction is consistent with the left and right directions. When the industrial robot performs the first and second actions, the hand moves linearly in the left-right direction relative to the main body.

5. The industrial robot according to claim 3, characterized in that, The first direction is consistent with the front-back direction. When the industrial robot performs the first and second actions, the hand moves linearly in the front-back direction relative to the main body.

6. A control method for an industrial robot, the industrial robot comprising: The hand is used to carry objects that are rectangular or square in shape and can move in the horizontal direction; An arm, to which the hand is connected; The main body is rotatably connected to the arm with the vertical direction as the axis of rotation. Two optical first detection mechanisms are mounted on the hand; as well as An optical second detection mechanism is mounted on the main body. Furthermore, if the position of the hand when it is loading and receiving the transport object placed on the designated receiving portion while the front end of the hand is moving away from the main body is defined as the receiving position, then the position of the hand when it is transferring the transport object loaded on the hand to the designated handover portion while the front end of the hand is moving away from the main body is defined as the handover position. Then, the following three actions are performed: the first action is the movement of the hand moving to the receiving position by moving the tip of the hand away from the main body; the second action is the movement of the hand, after receiving the object to be transported, moving to the receiving position by moving the tip of the hand closer to the main body; and the third action is the movement of the hand, carrying the object to be transported, moving to the hand-over position by moving the tip of the hand away from the main body, after the second action. When the hand performs the first and second actions, it moves linearly relative to the main body in a certain direction. If we take the direction of hand movement during the first and second actions as the first direction, and the direction orthogonal to the first direction and the up-down direction as the second direction, then... The first detection mechanism is a reflective detection mechanism comprising a first light-emitting part and a first light-receiving part. The first light-receiving part receives light emitted from the first light-emitting part and reflected by the object being transported. The two first detection units are configured with a gap between them in the second direction. The second detection mechanism is a transmissive detection mechanism having a second light-receiving part and a second light-emitting part. The second light-receiving part is composed of a line sensor or a region sensor, and the second light-emitting part is arranged opposite to the second light-receiving part at a predetermined interval in the vertical direction. During the first action, the two first detection mechanisms pass under the transported object placed on the receiving part. During the second action, one end face of the object being transported, mounted on the hand, passes between the second light-receiving part and the second light-emitting part in the second direction. The control method for the industrial robot is characterized by the following: During the first action, first position data and second position data are acquired. The first position data is the position data of the hand in the first direction when one of the two first detection mechanisms detects the object being transported. The second position data is the position data of the hand in the first direction when the other of the two first detection mechanisms detects the object being transported. During the second action, third position data is acquired. The third position data is the position data of one end face of the object being transported in the second direction detected by the second detection mechanism when the hand moves to a predetermined measurement position. During the third action, the position and orientation of the hand in the horizontal direction when reaching the handover position are corrected based on the first position data, the second position data, and the third position data.

Images