Robot teaching device and target position calculation method

Abstract

This invention provides a robot teaching device and a target position calculation method that can appropriately calculate the target position for transporting a flat object by determining the relative position between a predetermined marker and an optical sensor, and then using the optical sensor to calculate the position of the transport robot. [Solution] The robot teaching device 100 includes a robot control unit 110 that controls the operation of the transport robot 10, an optical sensor 50 that can sense predetermined markers P1 and P2 placed inside the chamber 60 and senses the inside of the chamber 60, a marker position calculation unit 120 that calculates a first relative position between the predetermined markers P1 and P2 and the optical sensor 50 based on the light reception status received via the predetermined markers P1 and P2, a robot position calculation unit 130 that calculates a second relative position between the optical sensor 50 and the transport robot 10 based on sensing by the optical sensor 50, and a target position calculation unit 140 that calculates a target position based on the first relative position and the second relative position.

Description

Technical Field

[0001] The present invention relates to a robot teaching device and a target position calculation method.

Background Art

[0002] In recent years, many robots have become widespread in the industrial field. Such robots are used, for example, for assembly, welding, conveyance and the like of electronic components and mechanical components, to achieve efficiency improvement and automation of factory production lines.

[0003] A conveyance robot that conveys wafers used in semiconductor manufacturing apparatuses performs teaching for conveying the wafer to an appropriate position, but the accuracy thereof depends on the operator's knowledge, skill level and the like, and there are cases where space saving to such an extent that a sufficient work space for the operator cannot be secured is required, so automation of the teaching is being promoted.

[0004] For example, in Patent Document 1, the turning angle of the arm at that time is detected based on the change between a state where the optical path of light emitted from an irradiation unit is not blocked by the arm and a state where the optical path is blocked. The position of the pivot shaft of the arm is specified based on the width of the arm, the position of the intersection of the optical path and the arm when the optical path is blocked, and the like, whereby performing teaching of the robot arm with high accuracy is disclosed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the technology disclosed in Patent Document 1, the position of the pivot axis of the arm is determined based on the passage and blockage of light emitted from the irradiation unit by rotating the arm, but misalignment of the irradiation unit and light receiving unit is not taken into consideration.

[0007] Therefore, the present invention aims to provide a robot teaching device and a target position calculation method that can appropriately calculate the target position for transporting a flat object by determining the relative position between a predetermined marker and an optical sensor and calculating the position of the transport robot using the optical sensor. [Means for solving the problem]

[0008] A robot teaching device according to one aspect of the present invention is a robot teaching device for a transport robot that transports a flat object to a target position in a chamber, comprising: a robot control unit that controls the operation of the transport robot; a predetermined marker placed in the chamber; an optical sensor that includes a light-emitting unit that emits light having a predetermined width and a light-receiving unit corresponding to the light-emitting unit, and is capable of sensing the predetermined marker and sensing the inside of the chamber; a marker position calculation unit that calculates a first relative position between the predetermined marker and the optical sensor based on a predetermined width and a light-receiving condition in which light emitted from the light-emitting unit is received by the light-receiving unit via the predetermined marker; a robot position calculation unit that calculates a second relative position between the optical sensor and the transport robot based on sensing by the optical sensor while the transport robot is moved in the chamber by the robot control unit; and a target position calculation unit that calculates a target position based on the first relative position and the second relative position.

[0009] In this embodiment, the marker position calculation unit calculates a first relative position between a predetermined marker and an optical sensor based on a predetermined width and the light reception conditions obtained when light emitted from a light emitter is received by a light receiver via a predetermined marker. The robot position calculation unit calculates a second relative position between the optical sensor and the transport robot based on sensing by the optical sensor while the transport robot is moved within the chamber by the robot control unit. The target position calculation unit then calculates the target position based on the first and second relative positions, thereby enabling the appropriate calculation of the target position for transporting a flat object.

[0010] In the above embodiment, the marker position calculation unit may calculate the first relative position based on the light reception conditions, including the width of the light received by the light receiving unit, relative to a predetermined width.

[0011] According to this embodiment, the marker position calculation unit calculates a first relative position based on the light reception conditions, including the width of light received by the light receiving unit, relative to a predetermined width, thereby enabling the appropriate calculation of the first relative position between a predetermined marker and an optical sensor.

[0012] In the above embodiment, the predetermined markers may be at least two or more.

[0013] According to this embodiment, since at least two or more predetermined markers are used, the first relative position between the predetermined markers and the optical sensor can be calculated more appropriately.

[0014] In the above embodiment, the designated marker may be a support pin on which a flat object is placed.

[0015] According to this embodiment, since support pins are used as predetermined markers, there is no need to place separate predetermined markers.

[0016] In the above embodiment, the optical sensor may include at least two sets of light-emitting units and light-receiving units corresponding to the light-emitting units.

[0017] According to this aspect, the optical sensor includes at least two or more sets of light-emitting units and light-receiving units corresponding to the light-emitting units, so that a predetermined mark can be appropriately detected. As a result, the first relative position between the predetermined mark and the optical sensor can be calculated more appropriately.

[0018] In the above aspect, a robot mark may be disposed on the transport robot, and the robot position calculation unit may calculate the second relative position by sensing the robot mark with the optical sensor.

[0019] According to this aspect, the robot position calculation unit calculates the second relative position by sensing the robot mark disposed on the transport robot with the optical sensor, so that the second relative position between the optical sensor and the transport robot can be appropriately calculated.

[0020] In the above aspect, the robot mark may have a cylindrical shape formed to block at least part of the light emitted from the light-emitting unit.

[0021] According to this aspect, since the robot mark has a cylindrical shape, it can be appropriately detected from any direction.

[0022] In the above aspect, the robot mark may have a notch shape formed to allow at least part of the light emitted from the light-emitting unit to pass therethrough.

[0023] According to this aspect, since the robot mark has a notch shape, it can be appropriately detected by utilizing the passage of light.

[0024] In the above aspect, the light-emitting unit and the light-receiving unit may be disposed on the side wall of the chamber.

[0025] According to this aspect, the inside of the chamber can be appropriately sensed by the light-emitting unit and the light-receiving unit disposed on the side wall of the chamber.

[0026] In the above aspect, the light projecting unit and the light receiving unit may be adjustable to a position where a predetermined mark can be sensed.

[0027] According to this aspect, since the positions (including angles) of the light projecting unit and the light receiving unit are adjustable, the predetermined mark can be appropriately sensed.

[0028] A target position calculation method according to one aspect of the present invention is a target position calculation method for calculating a target position, which is executed by a robot teaching device of a transfer robot that transfers a flat plate-shaped object to a target position in a chamber, wherein a predetermined mark is arranged in the chamber, the target position calculation method includes a light projecting unit that projects light having a predetermined width, and a light receiving unit corresponding to the light projecting unit, an optical sensor capable of sensing the predetermined mark and sensing the inside of the chamber is arranged, the target position calculation method comprises: a robot control step of controlling the operation of the transfer robot; a mark position calculation step of calculating a first relative position between the predetermined mark and the optical sensor based on the predetermined width and a light reception state of light received by the light receiving unit via the predetermined mark; a robot position calculation step of calculating a second relative position between the optical sensor and the transfer robot based on sensing by the optical sensor while moving the transfer robot inside the chamber in the robot control step; and a target position calculation step of calculating the target position based on the first relative position and the second relative position.

[0029] According to this aspect, in the mark position calculation step, the first relative position between the predetermined mark and the optical sensor is calculated based on the predetermined width and the light reception state in which the light projected from the light projecting unit is received by the light receiving unit via the predetermined mark, and in the robot position calculation step, the second relative position between the optical sensor and the transfer robot is calculated based on sensing by the optical sensor while moving the transfer robot inside the chamber in the robot control step. Then, in the target position calculation step, the target position is calculated based on the first relative position and the second relative position, so that the target position for transferring the flat plate-shaped object can be appropriately calculated. Effects of the Invention

[0030] According to the present invention, a robot teaching device and a target position calculation method can be provided that can appropriately calculate the target position for transporting a flat object by determining the relative position between a predetermined marker and an optical sensor and calculating the position of the transport robot using the optical sensor. [Brief explanation of the drawing]

[0031] [Figure 1] This is a schematic diagram showing the system configuration of the transport robot system 1 according to the first embodiment of the present invention. [Figure 2] This is a schematic diagram showing how the transport robot 10 operates in a clean environment. [Figure 3] This diagram schematically shows the arrangement of the first sensor 51 and the second sensor 52 located within the chamber 60. [Figure 4] This is a functional block diagram showing the functions of the robot teaching device 100 according to the first embodiment of the present invention. [Figure 5] This figure shows how two sets of optical sensors (first sensor 51 and second sensor 52) detect the positions of support pins P1 and P2 located on the stage S. [Figure 6] This figure shows how two sets of optical sensors (first sensor 51 and second sensor 52) detect robot markers placed on the hand 11 of the transport robot 10. [Figure 7] This is a flowchart showing the processing flow of the target position calculation method M100, which calculates the target position for transporting an object, as performed by the robot teaching device 100 according to the first embodiment of the present invention. [Figure 8] This figure shows an example of a robot marker Q2 in which an optical path is formed that allows the first light L10 and the second light L20 to pass through. [Figure 9] This figure shows how a pair of optical sensors (third sensor 53) detects the positions of support pins P1 and P2 located on the stage S. [Figure 10] This figure shows how a pair of optical sensors (third sensor 53) detects a robot marker placed on the hand 11 of the transport robot 10. [Figure 11] This figure shows how two sets of optical sensors (first sensor 51 and second sensor 52) detect the position of the support pin P2 located on the stage S. [Figure 12] This figure shows how two sets of optical sensors (first sensor 51 and second sensor 52) detect a robot marker located at the center (target position) of stage S. [Modes for carrying out the invention]

[0032] The embodiments of the present invention will be described below in detail with reference to the drawings. The embodiments described below are merely examples of how to implement the present invention and are not intended to limit the scope of the invention. Furthermore, to facilitate understanding of the explanation, the same reference numerals are used for identical components in each drawing whenever possible, and redundant explanations may be omitted.

[0033] <First Embodiment> [Configuration of the transport robot system] Figure 1 is a schematic diagram showing the system configuration of a transport robot system 1 according to a first embodiment of the present invention. As shown in Figure 1, the transport robot system 1 comprises a transport robot 10, a sensor monitoring device 20, a robot control device 30, an operating device 40, and an optical sensor 50. In this case, two sets of optical sensors (first sensor 51 and second sensor 52) (hereinafter sometimes collectively referred to as "sensor 50") are arranged in the chamber 60 as the optical sensor 50. The first sensor 51 and the second sensor 52 may be, for example, fiber optic sensors having a light-emitting unit that emits light and a light-receiving unit that can receive the light emitted from the light-emitting unit. Details regarding the arrangement of the first sensor 51 and the second sensor 52 will be described later.

[0034] The transport robot 10 is, for example, a horizontal articulated robot intended for wafer transport, and is a clean transport robot used for transport in clean environments in the manufacturing of semiconductor devices and flat panel displays, and in the medical and food industries. In this embodiment, the transport robot 10 is, for example, a two-axis or three-axis cylindrical coordinate type, and has a hand 11 as an end effector, and is described as a robot that holds and transports wafers (objects) with the hand 11.

[0035] The sensor monitoring device 20 controls and monitors the first sensor 51 and the second sensor 52 located in the chamber 60. For example, the sensor monitoring device 20 may control the light emitted from the light-emitting sections of the first sensor 51 and the second sensor 52, or monitor the light-receiving sections of the first sensor 51 and the second sensor 52 to detect the light received by each light-receiving section (such as the amount of light received and the range of light received).

[0036] The robot control device 30 is a device that controls the operation of the transport robot 10. For example, the robot control device 30 is connected to the operating device 40 and can acquire operation instruction information input to the operating device 40. Based on this operation instruction information, the robot control device 30 operates each axis of the transport robot 10, as well as the arms and hands 11, to start and stop the transport robot 10, pick up an object, transport and place it.

[0037] The operating device 40 is, for example, a teach pendant, and receives input from the operator regarding operation instruction information for the transport robot 10, specifically concerning transport operations that transport an object. Typically, the operator uses the teach pendant to input appropriate instruction information for, for example, starting and stopping the transport robot 10, as well as settings for the transport robot 10, the operation of the arm and hand 11, and the registration of teaching points.

[0038] Furthermore, regarding the registration of teaching points, the operator may sequentially register the teaching points along the movement path using a teach pendant while operating the transport robot 10, or the teaching points may be automatically registered in automatic teaching. Automatic teaching is effective, for example, in environments or situations where sufficient space (workspace) for the operator to enter cannot be secured.

[0039] In Figure 1, the operating device 40 is connected to the robot control device 30 via a cable, but it may also be connected wirelessly. That is, the operating device 40 and the robot control device 30 may be equipped with a communication unit for wireless communication. By connecting the robot control device 30 and the operating device 40 wirelessly, the operator can input operation instruction information while moving freely without being bothered by the presence of cables or having their range of movement limited by the length of the cables.

[0040] [Wafer transport process] Figure 2 is a schematic diagram showing how the transport robot 10 operates in a clean environment. As shown in Figure 2, the transport robot 10, installed in the workspace WS, holds the wafer W in its hand 11 and transports it to each stage S1 to S3 (hereinafter sometimes collectively referred to as "stage S") in the process chamber under vacuum conditions.

[0041] Specifically, the transport robot 10 operates its arms and hands 11 based on motion instruction information from the robot control device 30 to pick up wafers W and transport them to the destination stage S.

[0042] Here, the target position for transporting and placing the wafer W is, for example, the center of the stage S, and it is preferable that the wafer W be placed with high precision at the center of the stage S. The robot control device 30 actually transports the wafer W and places it at the target position, the center of the stage S, based on the teaching data. At that time, the robot control device 30 can generate high-precision teaching data by detecting predetermined markers placed on the stage S and appropriately determining the center position (target position) of the stage S based on these predetermined markers. As a result, the wafer W can be placed with high precision at the center of the stage S.

[0043] In other words, it is important to accurately determine the center position (target position) of stage S by appropriately detecting the positions of predetermined markers placed on stage S. Below, we will explain a method for accurately determining the center position (target position) of stage S by appropriately detecting the positions of predetermined markers placed on stage S using the first sensor 51 and the second sensor 52 placed in chamber 60.

[0044] [Placement of optical sensors] Figure 3 is a schematic diagram showing the arrangement of the first sensor 51 and the second sensor 52 located inside the chamber 60. As shown in Figure 3, a stage S is formed inside the chamber 60, and three support pins P1 to P3 are arranged on the stage S to support the wafer W to be transported. The three support pins P1 to P3 are arranged at equal intervals with respect to the center position of the stage S, which is the target position where the wafer W is transported and placed, and the positional relationship between each of the three support pins P1 to P3 and the center position of the stage S is known in advance.

[0045] Two sets of optical sensors, a first light-emitting unit 51E and a first light-receiving unit 51R (first sensor 51), and a second light-emitting unit 52E and a second light-receiving unit 52R (second sensor 52), are arranged on the side wall of the chamber 60.

[0046] As described above, the transport robot 10 is a clean transport robot used for transport in a clean environment, and the stage S is a vacuum environment. On the other hand, the first light-emitting unit 51E, the first light-receiving unit 51R, the second light-emitting unit 52E, and the second light-receiving unit 52R, which are located on the side wall of the chamber 60, are outside the vacuum environment, and the boundary with the stage S may be separated by a transparent material such as acrylic resin or glass. That is, the light emitted from the first light-emitting unit 51E and the second light-emitting unit 52E passes through the transparent material and enters the stage S (vacuum environment), and the first light-receiving unit 51R and the second light-receiving unit 52R can receive light from the stage S (vacuum environment) by passing through the transparent material.

[0047] Specifically, the first light-emitting unit 51E and the first light-receiving unit 51R are arranged to face each other via support pins P1 and P2 among the support pins P1 to P3. The first light L10 emitted from the first light-emitting unit 51E is partially shielded by the support pins P1 and P2, making it receivable by the first light-receiving unit 51R.

[0048] Similarly, the second light-emitting unit 52E and the second light-receiving unit 52R are arranged to face each other via support pins P1 and P2 among the support pins P1 to P3. The second light L20 emitted from the second light-emitting unit 52E is partially shielded by support pins P1 and P2 so that it can be received by the second light-receiving unit 52R. The first light-emitting unit 51E and the first light-receiving unit 51R, and the second light-emitting unit 52E and the second light-receiving unit 52R are arranged on the side walls of the chamber 60 such that the second light L20 and the first light L10 are not parallel to each other.

[0049] In this manner, two sets of optical sensors (first sensor 51 and second sensor 52) are arranged, and the information detected by the first sensor 51 and second sensor 52 is monitored (acquired) by the sensor monitoring device 20.

[0050] [Configuration of the robot teaching device] Figure 4 is a functional block diagram showing the functions of the robot teaching device 100 according to the first embodiment of the present invention. As shown in Figure 4, the robot teaching device 100 has a functional configuration comprising a robot control unit 110, a marker position calculation unit 120, a robot position calculation unit 130, and a target position calculation unit 140, and calculates the center position (target position) of the stage S based on the relative positions of a predetermined marker with the first sensor 51 and the second sensor 52, and the position of the transport robot 10 detected by the first sensor 51 and the second sensor 52.

[0051] Of these functions, the robot control unit 110 is a function of the robot control device 30. The marker position calculation unit 120, the robot position calculation unit 130, and the target position calculation unit 140 may all be provided in either the sensor monitoring device 20, which monitors information detected by the first sensor 51 and the second sensor 52, or the robot control device 30, or the functions may be distributed between the sensor monitoring device 20 and the robot control device 30. Furthermore, some or all of the functions may be provided in other information processing devices other than the sensor monitoring device 20 and the robot control device 30, in cooperation with the sensor monitoring device 20 and the robot control device 30.

[0052] The robot control unit 110 controls the operation of the transport robot 10. For example, the robot control unit 110 controls the operation of the transport robot 10 based on information detected by the first sensor 51 and the second sensor 52. Here, the information detected by the first sensor 51 and the second sensor 52 includes information based on predetermined markers (such as support pins) placed inside the chamber 60 and robot markers placed on the hand 11 of the transport robot 10.

[0053] The marker position calculation unit 120 calculates the first relative position between a predetermined marker and the first sensor 51 and the second sensor 52 based on the width of the first light L10 and second light L20 emitted from the first light-emitting unit 51E and the second light-emitting unit 52E, and the light reception conditions in which the first light L10 and second light L20 are received by the first light-receiving unit 51R and the second light-receiving unit 52R via a predetermined marker.

[0054] Figure 5 shows how two sets of optical sensors (first sensor 51 and second sensor 52) detect the positions of support pins P1 and P2 located on the stage S. As shown in Figure 5, the first light L10 and second light L20 emitted from the first light-emitting unit 51E and the second light-emitting unit 52E are partially blocked by the support pins P1 and P2 and received by the first light-receiving unit 51R and the second light-receiving unit 52R.

[0055] The first light beam L10 emitted from the first light-emitting unit 51E has a predetermined width (distance between outer casing L11 and outer casing L12). A portion of this first light beam L10 is shielded by support pins P1 and P2, and its width is reduced when it is received by the first light-receiving unit 51R (distance between outer casing L13 and outer casing L14).

[0056] Similarly, the second light L20 emitted from the second light-emitting unit 52E has a predetermined width (distance between outer casing L21 and outer casing L22). A portion of this second light L20 is shielded by the support pins P1 and P2, and its width is reduced when it is received by the second light-receiving unit 52R (distance between outer casing L23 and outer casing L24).

[0057] The marker position calculation unit 120 has prior knowledge of the size (e.g., diameter) of the support pins P1 and P2, and calculates the positions of the support pins P1 and P2 detected by the first sensor 51 and the second sensor 52 located in the chamber 60, based on the width of the first light L10 emitted from the first light emitter 51E, the width of the second light L20 emitted from the second light emitter 52E, and the light reception conditions (the width of the first light L10 and the width of the second light L20 received) received by the first light receiver 51R and the second light receiver 52R.

[0058] In other words, the marker position calculation unit 120 calculates the relative position (first relative position) between the support pins P1 and P2 and the first sensor 51 and the second sensor 52.

[0059] In this example, the positions of the support pins P1 and P2 were calculated based on the widths of the projected first light L10 and second light L20 and the widths of the received first light L10 and second light L20, but this is not the only way to do so. For example, the positions of the support pins P1 and P2 may be calculated based on the amount of light received by the first light receiving unit 51R and the second light receiving unit 52R (changes in the amount of light projected by the projected first light L10 and second light L20) and the light receiving range (changes in the light projection range of the projected first light L10 and second light L20).

[0060] Returning to the explanation of Figure 4, the robot position calculation unit 130 calculates the second relative position between the transport robot 10 (hand 11) and the first sensor 51 and the second sensor 52 based on the width of the first light L10 and second light L20 emitted from the first light emitter 51E and the second light emitter 52E, and the light reception status of the first light L10 and second light L20 received by the first light receiver 51R and the second light receiver 52R via the transport robot 10 (hand 11), while the transport robot control unit 110 moves the transport robot 10 (hand 11) within the chamber 60.

[0061] Figure 6 shows how two sets of optical sensors (first sensor 51 and second sensor 52) detect a robot marker placed on the hand 11 of the transport robot 10. As shown in Figure 6, the first light L10 and second light L20 emitted from the first light emitter 51E and second light emitter 52E are partially blocked by the robot marker Q1 (for example, a pin) and then received by the first light receiver 51R and second light receiver 52R.

[0062] At this time, the support pins P1 to P3, which are located on the stage S shown in Figure 5, are lowered or otherwise removed from the stage S. The robot control unit 110 then moves the transport robot 10 (hand 11) to a position where the robot marker Q1 located on the transport robot 10 (hand 11) blocks at least a portion of the first light L10 and second light L20 emitted from the first light-emitting unit 51E and the second light-emitting unit 52E.

[0063] Furthermore, although the robot marker Q1 is pre-placed on the transport robot 10 (hand 11), it is preferable to place it on the TCP (Tool Center Point) because the TCP is adjusted to the target position during robot teaching.

[0064] The first light L10 emitted from the first light-emitting unit 51E has a predetermined width (distance between outer casings L11 and L12). A portion of the first light L10 is blocked by the robot marker Q1, and the width is reduced when it is received by the first light-receiving unit 51R (distance between outer casings L11 and L15 and distance between outer casings L12 and L16). The first light L10 received by the first light-receiving unit 51R is divided into two parts (forming two receiving ranges).

[0065] Similarly, the second light L20 emitted from the second light-emitting unit 52E has a predetermined width (distance between outer casings L21 and L22). A portion of the second light L20 is blocked by the robot marker Q1, and its width is reduced when it is received by the second light-receiving unit 52R (distance between outer casings L21 and L25 and distance between outer casings L22 and L26). The second light L20 received by the second light-receiving unit 52R is divided into two parts (forming two receiving ranges).

[0066] The robot position calculation unit 130 has prior knowledge of the size (e.g., diameter) of the robot marker Q1, and calculates the position of the robot marker Q1 detected by the first sensor 51 and the second sensor 52 located in the chamber 60, based on the width of the first light L10 emitted from the first light emitter 51E, the width of the second light L20 emitted from the second light emitter 52E, and the light reception conditions (width and range of the first light L10 and the second light L20 received) received by the first light receiver 51R and the second light receiver 52R.

[0067] In other words, the robot position calculation unit 130 calculates the relative position (second relative position) between the robot marker Q1 and the first sensor 51 and the second sensor 52. Specifically, the robot position calculation unit 130 calculates the position (robot coordinate system) of the robot marker Q1 based on the axis angles of the transport robot 10 in the light reception conditions in which the robot marker Q1 is detected by the first sensor 51 and the second sensor 52.

[0068] Returning to the explanation of Figure 4, the target position calculation unit 140 calculates the target position based on the first relative position calculated by the marker position calculation unit 120 and the second relative position calculated by the robot position calculation unit 130.

[0069] At the first relative position, the positional relationship between the support pins P1 and P2 located on the stage S and the first sensor 51 (first light-emitting unit 51E and first light-receiving unit 51R) and the second sensor 52 (second light-emitting unit 52E and second light-receiving unit 52R) located in the chamber 60 can be determined. Furthermore, at the second relative position, the positional relationship between the first sensor 51 (first light-emitting unit 51E and first light-receiving unit 51R) and the second sensor 52 (second light-emitting unit 52E and second light-receiving unit 52R) located in the chamber 60 and the transport robot 10 (robot marker Q1 located on the hand 11) can be determined (robot coordinate system).

[0070] As a result, the target position calculation unit 140 calculates the positional relationship between the support pins P1 and P2 located on the stage S and the transport robot 10 (robot marker Q1 located on the hand 11) based on the first relative position and the second relative position (robot coordinate system). Furthermore, since the target position calculation unit 140 has prior knowledge of the positional relationship between the support pins P1 and P2 and the center position of the stage S, which is the target position where the wafer W will be transported and placed, it calculates the target position where the wafer W will be transported and placed based on the positional relationship between the support pins P1 and P2 located on the stage S and the transport robot 10 (robot marker Q1 located on the hand 11) (robot coordinate system).

[0071] [Method for calculating the target position when transporting a flat object] Next, we will explain in detail how to calculate the target position (center position of stage S) for transporting a flat object.

[0072] Figure 7 is a flowchart showing the processing flow of the target position calculation method M100, which calculates the target position for transporting an object executed by the robot teaching device 100 according to the first embodiment of the present invention. As shown in Figure 7, the target position calculation method M100 includes steps S110 to S190, each of which is mainly performed by a processor included in the sensor monitoring device 20, robot control device 30 and / or other information processing device that constitute the robot teaching device 100.

[0073] First, as explained using Figure 3, three support pins P1 to P3 are arranged on the stage S inside the chamber 60, and a first sensor 51 (first light emitter 51E and first light receiver 51R) and a second sensor 52 (second light emitter 52E and second light receiver 52R) for sensing inside the chamber 60 are arranged on the side wall of the chamber 60.

[0074] In step S110, the support pins are sensed within the chamber 60 by the first sensor 51 and the second sensor 52. Specifically, the sensor monitoring device 20 emits light of a predetermined width from the first light-emitting unit 51E and the second light-emitting unit 52E, and receives the light with the first light-receiving unit 51R and the second light-receiving unit 52R, respectively.

[0075] The sensor monitoring device 20 then acquires information based on the light emitted from the first light-emitting unit 51E and the second light-emitting unit 52E (such as the amount of light emitted and the light-emitting range (width)), and information based on the light received by the first light-receiving unit 51R and the second light-receiving unit 52R (such as the amount of light received and the light-receiving range).

[0076] In step S120, the robot teaching device 100 determines whether the support pins located in the chamber 60 can be sensed by the first sensor 51 and the second sensor 52. Specifically, based on the light received by the first light receiving unit 51R and the second light receiving unit 52R in step S110 (such as the amount of light received and the range of light received), the robot teaching device 100 determines whether a support pin detection state is in which a portion of the first light L10 and the second light L20 emitted from the first light emitting unit 51E and the second light emitting unit 52E is blocked by the support pins P1 and P2, as explained with reference to Figure 5.

[0077] If it is determined in step S120 that the support pin is detected, the process proceeds to step S130 ("Yes" in step S120). If it is determined in step S120 that the support pin is not detected, the process proceeds to step S140 ("No" in step S120).

[0078] If the process proceeds to step S140, the positions and / or angles of the first sensor 51 (first light-emitting unit 51E and first light-receiving unit 51R) and the second sensor 52 (second light-emitting unit 52E and second light-receiving unit 52R), which are located on the side wall of the chamber 60, are adjusted, and the processes of steps S110, S120, and S140 are repeated until it is determined that the support pin is detected ("Yes" in step S120). Here, the positions and / or angles of the first sensor 51 (first light-emitting unit 51E and first light-receiving unit 51R) and the second sensor 52 (second light-emitting unit 52E and second light-receiving unit 52R), which are located on the side wall of the chamber 60, are configured to be adjustable from outside the chamber 60 using mechanical and / or electrical means.

[0079] In step S130, the marker position calculation unit 120 calculates the first relative position between the support pins located inside the chamber 60 and the first sensor 51 (first light emitter 51E and first light receiver 51R) and the second sensor 52 (second light emitter 52E and second light receiver 52R) located on the side wall of the chamber 60. As a specific example, as explained with reference to Figure 5, the marker position calculation unit 120 calculates the positions of the support pins P1 and P2 located in the chamber 60 (first relative position with respect to the first sensor 51 and the second sensor 52) based on the width of the light emitted from the first light emitter 51E and the second light emitter 52E (first light L10 and second light L20) and the light reception conditions received by the first light receiver 51R and the second light receiver 52R.

[0080] In step S150, the first sensor 51 and the second sensor 52 sense the transport robot 10 (hand 11) inside the chamber 60. Specifically, with the support pins P1 to P3 located on the stage S lowered or otherwise removed from the stage S, the robot control unit 110 moves the transport robot 10 (hand 11) to a position where the robot markers located on the hand 11 are detected by the first sensor 51 and the second sensor 52. The sensor monitoring device 20 then emits light of a predetermined width from the first light emitter 51E and the second light emitter 52E, and acquires information based on the light received by the first light receiver 51R and the second light receiver 52R, respectively (such as the amount of light received and the range of light received).

[0081] In step S160, the robot teaching device 100 determines whether the robot marker placed on the hand 11 can be sensed by the first sensor 51 and the second sensor 52. Specifically, based on the light received by the first light receiving unit 51R and the second light receiving unit 52R in step S150 (such as the amount of light received and the range of light received), the robot teaching device 100 determines whether a robot marker detection state is in which a portion of the first light L10 and the second light L20 emitted from the first light emitting unit 51E and the second light emitting unit 52E is blocked by the robot marker Q1, as explained with reference to Figure 6.

[0082] If it is determined in step S160 that the robot marker has been detected, the process proceeds to step S170 ("Yes" in step S160). If it is determined in step S160 that the robot marker has not been detected, the process proceeds to step S180 ("No" in step S160).

[0083] If the process proceeds to step S180, the robot control unit 110 adjusts the position of the transport robot 10 (hand 11), and the processes of steps S150, S160, and S180 are repeated until it is determined that the robot marker has been detected ("Yes" in step S160).

[0084] In step S170, the robot position calculation unit 130 calculates the second relative position between the first sensor 51 (first light emitter 51E and first light receiver 51R) and the second sensor 52 (second light emitter 52E and second light receiver 52R) located on the side wall of the chamber 60, and the transport robot 10 (robot marker Q1 located on the hand 11). Specifically, the robot position calculation unit 130 calculates the position (robot coordinate system) of the robot marker Q1 based on the axis angles of the transport robot 10 in the light reception situation in which the robot marker Q1 is detected by the first sensor 51 and the second sensor 52.

[0085] In step S190, the target position calculation unit 140 calculates the target position based on the first relative position calculated in step S130 and the second relative position calculated in step S170. Specifically, the target position calculation unit 140 calculates the target position for transporting and placing the wafer W (robot coordinate system) based on the positional relationship (first relative position) between the support pins P1 and P2 placed on the stage S and the first sensor 51 and second sensor 52 placed on the chamber 60, and the positional relationship (second relative position) between the first sensor 51 and second sensor 52 placed on the chamber 60 and the robot marker Q1.

[0086] As described above, according to the robot teaching device 100 and target position calculation method M100 of the first embodiment of the present invention, three support pins P1 to P3 are arranged on the stage S in the chamber 60, and a first sensor 51 (first light emitter 51E and first light receiver 51R) and a second sensor 52 (second light emitter 52E and second light receiver 52R) are arranged on the side wall of the chamber 60. The marker position calculation unit 120 calculates the first relative position between the support pins P1 and P2 and the first sensor 51 and the second sensor 52 based on the first light L10 and second light L20 emitted by the first light emitter 51E and the second light emitter 52E, and the light reception status received by the first light receiver 51R and the second light receiver 52R via the support pins P1 and P2. The robot control unit 110 moves the transport robot 10 (hand 11) within the chamber 60, and the first sensor 51 and second sensor 52 sense the robot marker Q1 placed on the hand 11. The robot position calculation unit 130 calculates the second relative position (robot coordinate system) between the first sensor 51 and the second sensor 52 and the transport robot 10 (hand 11). Then, the target position calculation unit 140 calculates the target position (center position of the stage S) based on the first relative position calculated by the marker position calculation unit 120 and the second relative position calculated by the robot position calculation unit 130. As a result, by determining the relative positions between the support pins P1 and P2 and the first sensor 51 and the second sensor 52, and using the first sensor 51 and the second sensor 52 to calculate the position of the transport robot 10, the target position for transporting a flat object can be appropriately calculated.

[0087] In this embodiment, the relative position (first relative position) between the first sensor 51 and the second sensor 52 was calculated using support pins P1 and P2 placed on the stage S as predetermined markers. However, the method is not limited to this, and at least two of the three support pins P1 to P3 placed on the stage S can be used. In this way, by using support pins placed on the stage S as predetermined markers, it is not necessary to place any other predetermined markers.

[0088] On the other hand, the system is not limited to using support pins placed on the stage S as predetermined markers; other predetermined markers whose positional relationship to the target position is known in advance may also be placed. For example, by placing predetermined markers other than support pins, such as conical shapes other than cylindrical shapes, it becomes possible to calculate the relative position (first relative position) between the predetermined marker and the first sensor 51 and the second sensor 52 with higher accuracy, and to respond according to the surrounding environment and circumstances.

[0089] Furthermore, although this embodiment describes a pin-shaped object on the hand 11 as a robot marker, it is not limited to this, and for example, an optical path for passing the first light L10 and the second light L20 may be formed.

[0090] Figure 8 shows an example of a robot marker Q2 in which optical paths are formed to allow the first light L10 and the second light L20 to pass through. As shown in Figure 8, the robot marker Q2 has optical paths Q21 and Q22 formed to allow the first light L10 and the second light L20 to pass through.

[0091] For example, a robot marker Q2 is placed on the hand 11. The robot control unit 110 moves the transport robot 10 (hand 11) and the first light receiving unit 51R and the second light receiving unit 52R receive the first light L10 emitted from the first light emitting unit 51E and the second light L20 emitted from the second light emitting unit 52E. Based on the position where the amount of received light is maximum, the positional relationship (second relative position) between the first sensor 51 and the second sensor 52 and the robot marker Q2 (transport robot 10) may be calculated.

[0092] Furthermore, the shape of the marker shown in Figure 8 may be used as a predetermined marker that is placed separately in place of the support pin described above.

[0093] <Second Embodiment> Next, a second embodiment of the present invention will be described. In the second embodiment, descriptions of matters common to the first embodiment will be omitted or simplified, and the differences from the first embodiment will be described in detail. In the first embodiment, two sets of optical sensors (first sensor 51 and second sensor 52) were arranged on the side wall of the chamber 60, but the second embodiment differs from the first embodiment in that only one set of optical sensors is arranged.

[0094] Figure 9 shows how a pair of optical sensors (third sensor 53) detects the positions of support pins P1 and P2 located on the stage S. As shown in Figure 9, the third light L30 emitted from the third light-emitting unit 53E is partially blocked by the support pins P1 and P2 and received by the third light-receiving unit 53R.

[0095] The third light L30 emitted from the third light-emitting unit 53E has a predetermined width (distance between outer casing L31 and outer casing L32). A portion of the third light L30 is shielded by support pins P1 and P2, and its width is reduced when it is received by the third light-receiving unit 53R (distance between outer casing L31 and outer casing L33 and distance between outer casing L32 and outer casing L34). The third light L30 received by the third light-receiving unit 53R is divided into two parts (forming two receiving ranges).

[0096] The marker position calculation unit 120 has prior knowledge of the size (e.g., diameter) of the support pins P1 and P2, and calculates the positions of the support pins P1 and P2 detected by the third sensor 53 located in the chamber 60 based on the width of the third light L30 emitted from the third light emitter 53E and the light reception conditions (width and range of the received third light L30) received by the third light receiver 53R.

[0097] In other words, the marker position calculation unit 120 calculates the relative position (first relative position) between the support pins P1 and P2 and the third sensor 53. However, in this embodiment, unlike the first embodiment, the relative position in one direction (vertical direction in Figure 9) is calculated with high accuracy, and the relative position in the other direction (horizontal direction in Figure 9) may be calculated based on pre-determined design values.

[0098] Figure 10 shows how a pair of optical sensors (third sensor 53) detects a robot marker placed on the hand 11 of the transport robot 10. As shown in Figure 10, the third light L30 emitted from the third light emitter 53E is blocked by the hand 11, and a portion of the third light L30 passes through the robot marker Q3 (for example, a notch) formed on the hand 11 and is received by the third light receiver 53R.

[0099] At this time, the support pins P1 to P3, which are located on the stage S shown in Figure 9, do not need to be positioned on the stage S, for example, by lowering them. The robot control unit 110 then moves the transport robot 10 (hand 11) to a position where the robot mark Q3 (notch) formed on the transport robot 10 (hand 11) allows at least a portion of the third light L30 emitted from the third light projector 53E to pass through.

[0100] The third light L30 emitted from the third light-emitting unit 53E has a predetermined width (distance between outer casing L31 and outer casing L32). The third light L30 is shielded by the hand 11, and a portion of the third light L30 passes through the robot marker Q3 (notch) formed on the hand 11 and is received by the third light-receiving unit 53R (distance between outer casing L35 and outer casing L36).

[0101] The robot position calculation unit 130 has prior knowledge of the size of the robot marker Q3 (for example, the size of the notch), and calculates the position of the robot marker Q3 detected by the third sensor 53 located in the chamber 60 based on the width of the third light L30 emitted from the third light emitter 53E and the light reception conditions (width and range of the received third light L30) received by the third light receiver 53R.

[0102] In other words, the robot position calculation unit 130 calculates the relative position (second relative position) between the robot marker Q3 and the third sensor 53. Specifically, the robot position calculation unit 130 calculates the position (robot coordinate system) of the robot marker Q3 based on the angles of each axis of the transport robot 10 in the light reception conditions in which the robot marker Q3 is detected by the third sensor 53.

[0103] As mentioned above, in this embodiment, the relative position in one direction (vertical direction in Figure 9) is calculated with high accuracy, while the relative position in the other direction (horizontal direction in Figure 9) may be calculated based on pre-established design values.

[0104] The target position calculation unit 140 then calculates the positional relationship between the support pins P1 and P2 arranged on the stage S and the transport robot 10 (robot marker Q3 formed on the hand 11) based on the first relative position and the second relative position (robot coordinate system). Furthermore, the target position calculation unit 140 calculates the target position for transporting and placing the wafer W based on the positional relationship between the support pins P1 and P2 arranged on the stage S and the transport robot 10 (robot marker Q3 formed on the hand 11) (robot coordinate system).

[0105] As described above, according to the second embodiment of the present invention, since one set of optical sensors (third sensor 53) is used, the transport robot system can be configured more easily than when using multiple sets of optical sensors, and furthermore, the process of calculating the target position can be simplified.

[0106] In this embodiment, a notch was formed in the hand 11 as the robot marker Q3, but this is not the only option. For example, a pin, as described in the first embodiment of the present invention, may be placed on the hand 11 to serve as the robot marker.

[0107] <Example 1> Figure 11 shows how two sets of optical sensors (first sensor 51 and second sensor 52) detect the position of support pin P2 located on stage S. As shown in Figure 11, the first sensor 51 (first light emitter 51E and first light receiver 51R) and the second sensor 52 (second light emitter 52E and second light receiver 52R) sense support pin P2 from different directions out of the three support pins P1 to P3.

[0108] As a result, the marker position calculation unit 120 can appropriately calculate the relative positions of the support pin P2 and the first sensor 51 and the second sensor 52 as the first relative position.

[0109] <Modification 2> Figure 12 shows how two sets of optical sensors (first sensor 51 and second sensor 52) detect a robot marker located at the center (target position) of the stage S. As shown in Figure 12, the first light emitter 51E and the first light receiver 51R, and the second light emitter 52E and the second light receiver 52R are arranged so that the first light L10 and the second light L20 intersect (pass through) the center (target position) of the stage S.

[0110] For example, a jig 12 for position adjustment is placed on the hand 11, and a robot marker Q4 is placed on the jig 12 for position adjustment. Specifically, the jig 12 for position adjustment may be in the shape of a wafer W, and the robot marker Q4 may be placed at the center position and / or TCP of the jig 12 for position adjustment.

[0111] The robot control unit 110 moves the transport robot 10 (hand 11) so that the robot marker Q4 is detected by two sets of optical sensors (first sensor 51 and second sensor 52). In other words, the robot control unit 110 moves the transport robot 10 (hand 11) so that the robot marker Q4 aligns with the center (target position) of the stage S.

[0112] This allows the target position calculation unit 140 to appropriately calculate the center (target position) of the stage S (robot coordinate system).

[0113] The embodiments described above are provided to facilitate understanding of the present invention and are not intended to limit its interpretation. The elements, their arrangement, materials, conditions, shapes, and sizes, etc., of each embodiment are not limited to those exemplified and can be modified as appropriate. Furthermore, it is possible to partially substitute or combine the configurations shown in different embodiments. [Explanation of Symbols]

[0114] 1...Transport robot system, 10...Transport robot, 11...Hand, 12...Jig for position adjustment, 20...Sensor monitoring device, 30...Robot control device, 40...Operating equipment, 50, 51, 52, 53...Sensors, 51E, 52E, 53E...Light emitting unit, 51R, 52R, 53R...Light receiving unit, 60...Chamber, 100...Robot teaching device, 110...Robot control unit, 120...Marker position calculation unit, 130...Ro Bot position calculation unit, 140...Target position calculation unit, S, S1~S3...Stage, W...Wafer, WS...Workspace, P1~P3...Support pins, Q1, Q2, Q3, Q4...Robot markers, Q21, Q22...Optical path, L10, L20, L30...Light, L11~L16, L21~L26, L31~L36...Outer enclosure, M100...Target position calculation method, S110~S190...Each step of target position calculation method M100

Claims

1. A robot teaching device for a transport robot that transports a flat object to a target position in a chamber, A robot control unit that controls the operation of the transport robot, A predetermined marker placed inside the chamber, An optical sensor that includes a light-emitting unit that emits light having a predetermined width and a light-receiving unit corresponding to the light-emitting unit, and that is capable of sensing the predetermined marker and sensing the inside of the chamber, A mark position calculation unit calculates a first relative position between the predetermined mark and the optical sensor based on the predetermined width and the light reception conditions in which the light emitted from the light-emitting unit is received by the light-receiving unit via the predetermined mark, The robot control unit moves the transport robot within the chamber, and the robot position calculation unit calculates a second relative position between the optical sensor and the transport robot based on sensing by the optical sensor. The system includes a target position calculation unit that calculates the target position based on the first relative position and the second relative position, Robot teaching device.

2. The marker position calculation unit calculates the first relative position based on the light reception conditions, which include the width of the light received by the light receiving unit relative to the predetermined width. The robot teaching device according to claim 1.

3. The aforementioned designated markers are at least two or more. The robot teaching device according to claim 1.

4. The aforementioned predetermined marker is a pin on which the flat object is placed. The robot teaching device according to claim 1.

5. The optical sensor includes at least two sets of light-emitting units and light-receiving units corresponding to the light-emitting units. The robot teaching device according to claim 1.

6. The aforementioned transport robot is equipped with a robot marker, The robot position calculation unit calculates the second relative position when the robot marker is sensed by the optical sensor. The robot teaching device according to claim 1 or 5.

7. The robot marker is cylindrical in shape, formed to block at least a portion of the light emitted from the light-emitting unit. The robot teaching device according to claim 6.

8. The robot marker has a notch shape formed so that at least a portion of the light emitted from the light-emitting unit can pass through. The robot teaching device according to claim 6.

9. The light-emitting unit and the light-receiving unit are arranged on the side wall of the chamber. The robot teaching device according to claim 1.

10. The light-emitting unit and the light-receiving unit are adjustable to a position where the predetermined mark can be sensed. The robot teaching device according to claim 9.

11. A target position calculation method for calculating the target position, which is performed by a robot teaching device of a transport robot that transports a flat object to a target position in a chamber, A predetermined marker is placed inside the chamber, It includes a light-emitting unit that emits light having a predetermined width and a light-receiving unit corresponding to the light-emitting unit, and an optical sensor capable of sensing the predetermined marker and sensing the inside of the chamber is arranged therein. A robot control step that controls the operation of the transport robot, A mark position calculation step in which a first relative position between the predetermined mark and the optical sensor is calculated based on the predetermined width and the light reception conditions of the light receiving unit through the predetermined mark, In the robot control step, while moving the transport robot within the chamber, a robot position calculation step is performed in which a second relative position between the optical sensor and the transport robot is calculated based on sensing by the optical sensor. A target position calculation step includes calculating the target position based on the first relative position and the second relative position, Robot teaching method.

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