Pitch angle monitoring method and monitoring device

Abstract

The application provides a pitch angle monitoring method and a monitoring device, which monitors the pitch angle of a robot arm by using the monitoring device, and the monitoring device comprises a laser emitter, a laser receiver and a first reflective glass; the method comprises the following steps: the laser emitter emits laser light on a horizontal plane relative to a first direction and towards a second plane, the first direction is perpendicular to the second direction; the laser receiver receives and records the number of laser light reflected by the first reflective glass, and calculates the straight line distance between the initial number and the final number; according to the straight line distance between the initial number and the final number, and the vertical straight line distance between the vertical center line of the robot arm and the emitting end of one of the laser emitters, the pitch angle of the robot arm is calculated; according to the accurately monitored pitch angle, the number of emitted laser light is adjusted, and the pitch angle required by the robot arm is adjusted.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to a method and device for monitoring pitch angle. Background Technology

[0002] A prior patent application with application number CN114199193A discloses a tilt monitoring device, method, and robotic arm system. In particular, the tilt monitoring device includes: an object to be measured, placed on a robotic arm support structure; and laser fiber sensors, including a first laser fiber sensor and a second laser fiber sensor, which are respectively arranged in a centrally symmetrical manner at both ends of a blocking member between the robotic arm support structure and the robotic arm. The laser fiber sensors are used to emit laser beams toward the object to be measured in a parallel manner during the movement of the object to be measured and to receive the reflected light reflected from the object to be measured accordingly, so as to determine whether the object to be measured is tilted based on the reflected light.

[0003] However, existing technologies only use parallel laser beams at both ends, which can only determine whether the object under test is tilted, but cannot determine the specific tilt angle. The information obtained is limited, providing little help for subsequent adjustments and robot arm calibration. Therefore, there is an urgent need for a device that can determine the specific tilt angle. Summary of the Invention

[0004] The purpose of this invention is to provide a method and device for monitoring pitch angle, which adjusts the number of emitted lasers based on the accurately monitored pitch angle, and simultaneously adjusts the required pitch angle of the robot arm, thereby improving the calibration accuracy of the robot arm.

[0005] To achieve the above objectives, the present invention provides a method for monitoring pitch angle, which uses a monitoring device to monitor the pitch angle of a robot arm. The monitoring device includes a laser emitter disposed on a first surface inside the housing and located on the upper and lower sides of the robot arm, a laser receiver disposed on the first surface inside the housing and located on the upper and lower sides of the robot arm, and a first reflective glass disposed on a second surface opposite to the first surface.

[0006] The method includes:

[0007] The laser emitter emits a laser beam at an angle relative to a first direction on a horizontal plane toward the second surface. The first direction is perpendicular to the second direction, and the second direction is the extension direction of the robot arm.

[0008] The laser receiver receives and records the number of laser points reflected by the first reflective glass, and calculates the straight-line distance between the initial number of points and the final number of points;

[0009] The pitch angle of the robot arm is calculated based on the straight-line distance between the initial point and the final point, and the straight-line vertical distance between the vertical centerline of the robot arm and the emitting end of one of the laser emitters.

[0010] Optionally, calculating the straight-line distance between the initial number of points and the final number of points includes the following steps:

[0011] Measure the angle α between the laser emitter and the first direction;

[0012] Measure the straight-line distance 'a' between the second reflective glass and the first reflective glass;

[0013] Based on the angle α between the laser emitter and the first direction, and the straight-line distance a between the second reflective glass and the first reflective glass, the straight-line distance c between the first point of the first reflective glass irradiated by the laser and the initial end of the first reflective glass is calculated. Based on the straight-line distance c, the straight-line distance c between the laser receiver and the adjacent points is calculated to be twice the straight-line distance.

[0014] The straight-line distance between the initial number of points and the final number of points is twice the straight-line distance c multiplied by the total number of points recorded by the laser receiver.

[0015] Optionally, the formula for calculating the straight-line distance between the initial number of points and the final number of points is as follows:

[0016] Calculate the straight-line distance c between the first point on the first reflective glass irradiated by the laser and the initial end of the first reflective glass:

[0017] c = a * tanα;

[0018] The straight-line distance between the initial point number and the final point number is calculated as follows:

[0019] △L=△e*2*c;

[0020] That is, △L=△e*2*a*tanα;

[0021] Wherein, the calculation of the straight-line distance c between the first point of the first reflective glass irradiated by the laser and the initial end of the first reflective glass conforms to the tangent function;

[0022] a is the straight-line distance between the second reflective glass and the first reflective glass;

[0023] △e represents the number of laser points received by the laser receiver.

[0024] Optionally, based on the straight-line distance between the initial and final points, and the vertical straight-line distance between the vertical centerline of the robot arm and the emitting end of one of the laser emitters, the formula for calculating the tilt angle or elevation angle of the robot arm is as follows:

[0025] β = arctan(g / ΔL);

[0026] That is, β=arctan(g / (2*Δe*a*tanα));

[0027] Wherein, g is the vertical straight-line distance between the vertical centerline of the robot arm and the emitting end of the first laser emitter, and the first laser emitter is located on the lower or upper side of the robot arm.

[0028] Optionally, based on the straight-line distance between the initial and final points, and the vertical straight-line distance between the vertical centerline of the robot arm and the emitting end of one of the laser emitters, the formula for calculating the elevation or depression angle of the robot arm is as follows:

[0029] β = arctan((dg) / △L);

[0030] That is, β=arctan((dg) / (2*Δe*a*tanα));

[0031] Where d is the vertical straight-line distance between the emitting ends of the two laser emitters; g is the vertical straight-line distance between the vertical centerline of the robot arm and the emitting end of the first laser emitter, which is located on the lower or upper side of the robot arm.

[0032] Optionally, when the total length of the laser receiver in the second direction is L, the total number of laser points that the laser receiver can receive is n:

[0033] n = L / (2*a*tanα).

[0034] A monitoring device includes a housing, a laser emitter, a first reflective glass, a laser receiver, a second reflective glass, and a computing unit;

[0035] The housing has a first surface and a second surface facing each other, and a robot arm is provided inside the housing along a second direction, the robot arm being positioned between the first surface and the second surface; a laser emitter is located on the first surface and above and below the robot arm; a first reflective glass is located on the second surface, with its initial end facing the laser emitter in a first direction; a second reflective glass is located on the first surface and covers the laser receiver; the laser receiver is located on the first surface and above and below the robot arm; the first direction and the second direction are perpendicular to each other.

[0036] The laser emitter is used to emit a laser beam at an angle relative to the first direction on a horizontal plane toward the second surface;

[0037] The laser receiver is used to receive and record the number of laser points reflected by the first reflective glass;

[0038] The calculation unit calculates the straight-line distance between the initial point number and the final point number; based on the straight-line distance between the initial point number and the final point number, and the vertical straight-line distance between the vertical centerline of the robot arm and the emitting end of one of the laser emitters, the pitch angle of the robot arm is calculated.

[0039] Optionally, a light shield may also be provided on the edge of the robot arm.

[0040] Optionally, the laser emitter forms an angle α with the first direction.

[0041] The beneficial effects of this invention are as follows:

[0042] The pitch angle monitoring method provided in this invention can determine whether the robot arm is in a pitch state and calculate the pitch angle of the robot arm. This allows for the adjustment of the number of lasers emitted by the laser emitter based on the accurately calculated pitch angle, and also adjusts the required pitch angle of the robot arm based on the calculated pitch angle, thereby improving the calibration accuracy of the robot arm. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the monitoring device structure in this invention;

[0044] Figure 2 This is a flowchart of the pitch angle monitoring method in this invention;

[0045] Figure 3 This is a flowchart illustrating the calculation of the straight-line distance between the initial number of points and the final number of points in this invention;

[0046] Figure 4This is a schematic diagram of the pitch angle of the robot arm in this invention;

[0047] Figure 5 This is a schematic diagram of the structure of the robot arm in this invention, in which laser emitters and laser receivers are provided on both the upper and lower sides.

[0048] Figure Labels

[0049] 1. Housing; 2. Laser emitter; 3. First reflective glass; 4. Laser receiver; 5. Second reflective glass; 6. Robotic arm; 7. Light shield. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art. The terms "comprising" and similar expressions used herein mean that the element or object preceding the word covers the element or object listed following the word and its equivalents, but do not exclude other elements or objects.

[0051] To address the problems existing in the prior art, embodiments of the present invention provide a method for monitoring pitch angle. A monitoring device is used to monitor the pitch angle of a robot arm 6. The monitoring device includes a housing 1, a laser emitter 2, a first reflective glass 3, a laser receiver 4, a second reflective glass 5, and a computing unit. The housing 1 has opposing first and second surfaces, and the robot arm 6 is disposed within the housing 1 along a second direction, between the first and second surfaces. The laser emitter 2 is disposed on the first surface and located above and below the robot arm 6. The first reflective glass 3 is disposed on the second surface, with its initial end opposite to the laser emitter 2 in the first direction. Two reflective glass panes 5 are disposed on the first surface and cover the laser receiver 4; the laser receiver 4 is disposed on the first surface and located on the upper and lower sides of the robot arm 6; the first direction and the second direction are perpendicular to each other; the laser emitter 2 is used to emit laser light at an angle relative to the first direction towards the second surface on a horizontal plane; the laser receiver 4 is used to receive and record the number of laser points reflected by the first reflective glass pane 3; the calculation unit calculates the straight-line distance between the initial number of points and the final number of points; based on the straight-line distance between the initial number of points and the final number of points, and the vertical straight-line distance between the vertical centerline of the robot arm 6 and the emitting end of one of the laser emitters 2, the pitch angle of the robot arm 6 is calculated.

[0052] The methods for monitoring the pitch angle include, for example, Figure 2 As shown:

[0053] S01: The laser emitter 2 emits a laser beam at an angle relative to the first direction on a horizontal plane toward the second surface. The first direction is perpendicular to the second direction, and the second direction is the extension direction of the robot arm 6.

[0054] S02: The laser receiver 4 receives and records the number of laser points reflected by the first reflective glass 3, and calculates the straight-line distance between the initial number of points and the final number of points;

[0055] S03: Calculate the pitch angle of the robot arm 6 based on the straight-line distance between the initial point number and the final point number, and the vertical straight-line distance between the vertical centerline of the robot arm 6 and the emitting end of one of the laser emitters 2.

[0056] The pitch angle monitoring method provided in this invention can both determine whether the robotic arm 6 is in a pitch state and calculate the pitch angle of the robotic arm 6. Based on the accurately calculated pitch angle, the number of laser beams emitted by the laser emitter 2 can be adjusted, and the required pitch angle of the robotic arm 6 can be adjusted accordingly, improving the calibration accuracy of the robotic arm 6. This effectively prevents scratches that may occur when the robotic arm 6 is gripping a wafer, thus protecting the wafer. The pitch angle monitoring method provided in this invention can also play a predictive role, accurately predicting whether the robotic arm 6 will pitch before an accident occurs and addressing it accordingly, preventing potential problems.

[0057] Specifically, this invention applies the method of laser reflection angle to a dry etching machine robot. By actively monitoring the specific height of the robot arm 6 and placing two laser emitters 2 on the upper and lower sides of the robot arm 6, the number of light spots received by the laser receiver 4 is recorded by observing the blocking of reflected light when the robot arm 6 pitches, and the pitch angle is calculated. The structure is simple, has strong anti-interference capabilities, and is highly adaptable.

[0058] In one embodiment, the calculation of the straight-line distance between the initial number of points and the final number of points is as follows: Figure 3 As shown, it includes the following steps:

[0059] S10: Measure the angle α between the laser emitter 2 and the first direction, see [reference]. Figure 1 As shown;

[0060] S20: Measure the straight-line distance 'a' between the second reflective glass 5 and the first reflective glass 3. (See below) Figure 1 As shown;

[0061] S30: Based on the angle α between the laser emitter 2 and the first direction, and the straight-line distance a between the second reflective glass 5 and the first reflective glass 3, calculate the distance from the first point on the first reflective glass 3 irradiated by the laser to the initial end of the first reflective glass 3 (the initial end can be understood as...). Figure 1 In the example, the straight-line distance c between the lower ends of the first reflective glass 3 is calculated based on the straight-line distance c, and the straight-line distance between the adjacent points received by the laser receiver 4 is twice the straight-line distance c.

[0062] In this step, utilizing the principle of light reflection, it can be determined that the straight-line distance between adjacent points on the first reflective glass 3 (i.e., the distance in the second direction) is consistent with the straight-line distance between adjacent points received by the laser receiver 4. Simultaneously, the straight-line distance c, calculated based on the angle α between the laser emitter 2 and the first direction, and the straight-line distance a between the second reflective glass 5 and the first reflective glass 3, is half the straight-line distance between adjacent points.

[0063] S40: The straight-line distance between the initial number of points and the final number of points is twice the straight-line distance c multiplied by the total number of points recorded by the laser receiver 4.

[0064] In this step, the distance between adjacent laser points received by the laser receiver 4 corresponds one-to-one with the twice straight-line distance c. Therefore, the twice straight-line distance c multiplied by the total number of points recorded by the laser receiver 4 can be used to obtain the straight-line distance between the initial number of points and the final number of points, that is, the distance in the second direction.

[0065] In one embodiment, the formula for calculating the straight-line distance between the initial number of points and the final number of points is as follows:

[0066] Calculate the straight-line distance c between the first point of the first reflective glass 3 irradiated by the laser and the initial end of the first reflective glass 3:

[0067] c = a * tanα;

[0068] The straight-line distance between the initial point number and the final point number is calculated as follows:

[0069] △L=△e*2*c;

[0070] That is, △L=△e*2*a*tanα;

[0071] The calculation of the straight-line distance c between the first point of the first reflective glass 3 irradiated by the laser and the initial end of the first reflective glass 3 conforms to the tangent function.

[0072] a is the straight-line distance between the second reflective glass 5 and the first reflective glass 3;

[0073] △e represents the number of laser points received by the laser receiver 4.

[0074] In one embodiment, the calculation is based on the straight-line distance between the initial and final point counts, and the straight-line distance between the robot arm 6 and one of the laser emitters 2 in the vertical direction, such as... Figure 4As shown, specifically, when the robotic arm 6 pitches, it blocks the laser beam, reducing the number of laser points received by the laser receiver 4. In other words, the pitch angle determines the number of laser points, so the pitch angle can be calculated from the number of laser points. The formula for calculating the pitch angle of the robotic arm 6 is as follows:

[0075] β = arctan(g / ΔL);

[0076] That is, β=arctan(g / (2*Δe*a*tanα));

[0077] Where g is the vertical straight-line distance between the vertical centerline of the robot arm 6 and the emitting end of the first laser emitter, which is located on the lower or upper side of the robot arm. In this example, the distance g is a known quantity and can be measured using an auxiliary measuring instrument. When the robot arm 6 is tilted downwards, it blocks the laser emitted by the lower laser emitter 2. The downward blocking distance of the robot arm 6 is g. At this time, the tilt angle of the robot arm 6 can be calculated using the calculation formula in this embodiment.

[0078] In one embodiment, the formula for calculating the elevation angle or depression angle of the robot arm 6, based on the straight-line distance between the initial and final point counts and the straight-line distance between the robot arm 6 and one of the laser emitters 2 in the vertical direction, is as follows:

[0079] β = arctan((dg) / △L);

[0080] That is, β=arctan((dg) / (2*Δe*a*tanα));

[0081] Where d is the vertical straight-line distance between the emitting ends of the two laser emitters 2, and d is a known quantity; g is the vertical straight-line distance between the vertical centerline of the robot arm and the emitting end of the first laser emitter, which is located relative to the lower or upper side of the robot arm. When the robot arm 6 tilts upward, it blocks the laser emitted by the upper laser emitter 2, and the blocking distance of the robot arm 6 is dg. At this time, the tilt angle of the robot arm 6 can be calculated using the calculation formula in this embodiment.

[0082] In one embodiment, when the total length of the laser receiver 4 in the second direction is L, the total number of laser points that the laser receiver 4 can receive is n:

[0083] n = L / (2*a*tanα).

[0084] The setup in this embodiment is used to assist in verifying whether the robot arm 6 has pitched. Specifically, when the robot arm 6 is not placed inside the housing 1, the laser emitter 2 is activated to emit a laser. According to the above formula, the total number of laser points that the laser receiver 4 can receive is calculated as n. Then, the robot arm 6 is extended into the housing 1, and the number of laser points that the laser receiver 4 can receive, n1, is calculated again. The magnitudes of n1 and n are compared. When the magnitudes of n1 and n are the same, the robot arm 6 has not pitched. When the number of points of n1 is less than that of n, it proves that the robot arm 6 has pitched and needs to be calibrated.

[0085] The present invention also provides a monitoring device that calculates the pitch angle of a robot arm 6 using the aforementioned pitch angle monitoring method. The monitoring device includes a housing 1, a laser emitter 2, a first reflective glass 3, a laser receiver 4, a second reflective glass 5, and a calculation unit. Figure 1 As shown;

[0086] During installation and debugging of the monitoring equipment, two laser emitters 2 are mounted along the same vertical line on the first surface of the housing 1, with a straight-line distance of d between them. Next, two laser receivers 4 are mounted along a second direction on the first surface of the housing 1, maintaining the laser receivers 4 at the same height as the laser emitters 2. Then, a second reflective glass 5 is placed over the laser receivers 4, and the second reflective glass 5 is made of a semi-transparent material. This serves both to reflect the laser light and to allow the laser light to be received by the laser receivers 4 through the second reflective glass 5. Finally, a first reflective glass 3 is mounted on the second surface of the housing 1 to reflect the laser light emitted by the laser emitters 2. It should be noted that the vertical height of the first reflective glass 3 is at least d.

[0087] The robot arm 6 is inserted into the housing 1, and the laser emitter 2 is activated. The number of points received by the laser receiver 4 is used to determine whether the robot arm 6 is pitching. If the robot arm 6 is pitching, it needs to be calibrated.

[0088] In one embodiment, the monitoring device further includes a light-shielding plate 7 disposed on the edge of the robotic arm 6, in Figure 5In the example, the light-shielding plate 7 is vertically mounted on the robot arm 6. When the robot arm 6 is not pitching, the light-shielding plate 7 is positioned between the upper and lower laser emitters 2, and will not block the laser emitted by the laser emitters 2. Only when the robot arm 6 pitches will the light-shielding plate 7 block the laser, thus reducing the number of laser points received by the laser receiver 4. Figure 1 In the example, there are two light-shielding plates 7, which are symmetrically arranged about the robot arm 6.

[0089] In one embodiment, the laser emitter 2 forms an angle α with the first direction, such as... Figure 1 As shown. In actual use, the angle α can be adjusted, which changes the number of laser points received by the laser receiver 4, making the device more versatile and more accurate in monitoring the pitch angle of the robotic arm 6.

[0090] In summary, the pitch angle monitoring method provided in this invention can determine whether the robot arm 6 is in a pitch state and calculate the pitch angle of the robot arm 6. Therefore, the number of lasers emitted by the laser emitter 2 can be adjusted according to the accurately calculated pitch angle, and the required pitch angle of the robot arm 6 can be adjusted according to the calculated pitch angle, thereby improving the calibration accuracy of the robot arm 6.

[0091] While embodiments of the present invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations fall within the scope and spirit of the invention as set forth in the claims. Furthermore, the invention described herein may have other embodiments and can be implemented or carried out in various ways.

Claims

1. A method for monitoring pitch angle, characterized in that, The pitch angle of the robot arm is monitored using a monitoring device, which includes a laser emitter located on the first surface inside the housing and on the upper and lower sides of the robot arm, a laser receiver located on the first surface inside the housing and on the upper and lower sides of the robot arm, and a first reflective glass located on a second surface opposite to the first surface. The method includes: The laser emitter emits a laser beam at an angle relative to a first direction on a horizontal plane toward the second surface. The first direction is perpendicular to the second direction, and the second direction is the extension direction of the robot arm. The laser receiver receives and records the number of laser points reflected by the first reflective glass, and calculates the straight-line distance between the initial number of points and the final number of points; The pitch angle of the robot arm is calculated based on the straight-line distance between the initial and final points, and the vertical straight-line distance between the vertical centerline of the robot arm and the emitting end of one of the laser emitters; wherein, the calculation of the straight-line distance between the initial and final points includes the following steps: Measure the angle α between the laser emitter and the first direction; Measure the straight-line distance 'a' between the second reflective glass and the first reflective glass; Based on the angle α between the laser emitter and the first direction, and the straight-line distance a between the second reflective glass and the first reflective glass, the straight-line distance c between the first point of the first reflective glass irradiated by the laser and the initial end of the first reflective glass is calculated. Based on this straight-line distance c, the straight-line distance c between adjacent points received by the laser receiver is calculated to be twice the straight-line distance c. The formula for calculating the straight-line distance c is: c = a * tanα. The straight-line distance ΔL between the initial point and the final point is twice the straight-line distance c multiplied by the total number of points recorded by the laser receiver. The formula for calculating the straight-line distance ΔL is: △L=△e*2*c; That is, △L = △e * 2 * a * tanα; Wherein, the calculation of the straight-line distance c between the first point of the first reflective glass irradiated by the laser and the initial end of the first reflective glass conforms to the tangent function; △e represents the number of laser points received by the laser receiver.

2. The method for monitoring pitch angle according to claim 1, characterized in that, The formula for calculating the tilt angle or pitch angle of the robot arm is as follows, based on the straight-line distance between the initial and final points, and the vertical straight-line distance between the vertical centerline of the robot arm and the emitting end of one of the laser emitters: β = arctan(g / ΔL); That is, β=arctan(g / (2*△e*a*tanα)); Wherein, g is the vertical straight-line distance between the vertical centerline of the robot arm and the emitting end of the first laser emitter, and the first laser emitter is located on the lower or upper side of the robot arm.

3. The method for monitoring pitch angle according to claim 1, characterized in that, The formula for calculating the elevation or depression angle of the robot arm, based on the straight-line distance between the initial and final points and the vertical straight-line distance between the vertical centerline of the robot arm and the emitting end of one of the laser emitters, is as follows: β = arctan((dg) / ΔL); That is, β=arctan((dg) / (2*△e*a*tanα)); Where d is the vertical straight-line distance between the emitting ends of the two laser emitters; g is the vertical straight-line distance between the vertical centerline of the robot arm and the emitting end of the first laser emitter, which is located on the lower or upper side of the robot arm.

4. The method for monitoring pitch angle according to claim 1, characterized in that, When the total length of the laser receiver in the second direction is L, the total number of laser points that the laser receiver can receive is n: n = L / (2*a*tanα).

5. A monitoring device, characterized in that, The monitoring device includes a housing, a laser emitter, a first reflective glass, a laser receiver, a second reflective glass, and a computing unit, for performing the pitch angle monitoring method according to any one of claims 1 to 4; The housing has a first surface and a second surface facing each other, and a robot arm is provided inside the housing along a second direction, the robot arm being positioned between the first surface and the second surface; a laser emitter is located on the first surface and above and below the robot arm; a first reflective glass is located on the second surface, with its initial end facing the laser emitter in a first direction; a second reflective glass is located on the first surface and covers the laser receiver; the laser receiver is located on the first surface and above and below the robot arm; the first direction and the second direction are perpendicular to each other. The laser emitter is used to emit a laser beam at an angle relative to the first direction on a horizontal plane toward the second surface; The laser receiver is used to receive and record the number of laser points reflected by the first reflective glass; The calculation unit calculates the straight-line distance between the initial number of points and the final number of points; The pitch angle of the robot arm is calculated based on the straight-line distance between the initial point and the final point, and the straight-line vertical distance between the vertical centerline of the robot arm and the emitting end of one of the laser emitters.

6. The monitoring device according to claim 5, characterized in that, It also includes a light shield located on the edge of the robot arm.

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