Automatic correction device and method for mechanical arm

Abstract

The invention relates to a mechanical arm automatic correction device and method, and the main structure comprises a mechanical arm, the mechanical arm is provided with an optical photographing mechanism, one side of the mechanical arm is provided with a wafer storage mechanism, the wafer storage mechanism is provided with an image information code, and the optical photographing mechanism is in information connection with an optical identification module. The optical identification module is internally provided with an information code analysis unit, an object distance analysis unit and a wafer center analysis unit. Therefore, a user can shoot an image information code through the optical shooting mechanism to carry out a first position correction action of the mechanical arm, then the optical shooting mechanism shoots a wafer and carries out a focusing action, and the object distance analysis unit is matched with the wafer center analysis unit to calculate the distance between the mechanical arm and the center point of the wafer; therefore, the effect of secondary correction is achieved. In this way, the rapid and accurate correction action is achieved.

Description

Technical Field

[0001] The present invention provides a mechanical arm automatic correction device with fast and accurate correction action and a method thereof. Background Art

[0002] Since the structure and production of semiconductor wafers are quite sophisticated, the requirements for storage and transportation are also high. When storing wafers, they are placed and stored in special storage carriers to match various types of storage environments, such as vacuum storage or inert gas storage. When transporting, in addition to directly transporting the carrier, the wafer can also be opened and taken out, but when taking out the internal wafer, most of them will use a robotic arm to carry out the pick-and-place action to prevent fragmentation or damage during transportation.

[0003] However, before the robot can pick and place, it must first completely locate the distance between the robot and the wafer carrier, so that it can correctly perform the pick and place action. The positioning action can be divided into automatic or manual methods to perform the pick and place action. If it is manual, it can use visual or mechanical measurement methods to provide relevant distance information to assist the user in the positioning action of the robot arm. If the automated robot arm is picking and placing, it uses multiple sensors and various types of measurements to correctly allow the robot arm to perform positioning actions.

[0004] If the positioning action is not accurate enough, it may cause various problems when the robot arm picks and places, increasing the probability of defective products. However, if the positioning action is to be performed correctly, multiple sensors are required to cooperate with each other, which will increase the cost of use.

[0005] Therefore, how to solve the above common problems and shortcomings is the direction that the applicant of the present invention and the relevant manufacturers engaged in this industry want to study and improve. Summary of the invention

[0006] In view of the above-mentioned shortcomings, the applicant of the present invention has collected relevant information, conducted multiple evaluations and considerations, and, with the years of experience accumulated in this industry, continuously tried and modified, and designed this invention of an automatic correction device and method for a robotic arm that uses a simple mechanism to achieve a complete correction action.

[0007] The main purpose of the present invention is to achieve a simple and accurate correction effect by using an optical photographic mechanism.

[0008] To achieve the above-mentioned objectives, the main structure of the present invention includes: a robotic arm, a wafer storage mechanism arranged at one side of the robotic arm, an image information code arranged on the wafer storage mechanism, an optical photography mechanism arranged on the robotic arm, an optical recognition module connected to the optical photography mechanism, an information code analysis unit arranged in the optical recognition module, an object distance analysis unit arranged in the optical recognition module, and a wafer center analysis unit arranged in the optical recognition module.

[0009] With the above structure, when the user wants to use the robot to take out the wafer, the robot can automatically perform the correction action. First, the image information code is photographed by the optical photography mechanism, and the image information code is analyzed by the information code analysis unit to obtain the relevant position information, so that the robot can perform the first correction action.

[0010] When the first correction action is performed, the approximate position of the wafer storage mechanism can be known. At this time, the optical photography mechanism is focused on the wafer in the wafer storage mechanism, and the object distance analysis unit can be used to calculate the wafer distance between the optical photography mechanism and the wafer through the focal length of the lens in the optical photography mechanism and the distance between the lens and the photosensitive imaging position in the optical photography mechanism. After the wafer distance is calculated, the wafer center analysis unit is used to calculate the distance between the robotic arm and the optical photography mechanism, the wafer distance, and the width of the wafer, so as to achieve the second correction action, so as to have a complete correction effect, and the wafer pick-up and placement action can be performed.

[0011] In this way, the above method can be used to allow the robot arm to quickly and accurately complete the correction action, and it can be achieved only by using the shooting action, so that a complete and fast correction action can be achieved at a lower cost.

[0012] By using the above technology, the problems of high cost or poor accuracy of the commonly used correction methods can be overcome, thereby achieving the practical progress of the above advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a three-dimensional perspective view of a preferred embodiment of the present invention.

[0014] Figure 2 Schematic diagram of the structural block of a preferred embodiment of the present invention.

[0015] Figure 3 Flow chart of the steps of a preferred embodiment of the present invention.

[0016] Figure 4 Schematic diagram of shooting according to a preferred embodiment of the present invention.

[0017] Figure 5 FIG. 4 is a schematic diagram of focal length of a preferred embodiment of the present invention.

[0018] Figure 6 Schematic diagram of center calculation of a preferred embodiment of the present invention.

[0019] Figure 7 This is a three-dimensional perspective view of another preferred embodiment of the present invention.

[0020] Figure 8 The figure is a flow chart of another preferred embodiment of the present invention.

[0021] Fig. 9 FIG. 4 is a schematic diagram of warpage detection according to another preferred embodiment of the present invention.

[0022] Fig.10 This is a three-dimensional perspective view of another preferred embodiment of the present invention.

[0023] Fig.11 This is a flow chart of steps of another preferred embodiment of the present invention.

[0024] Fig.12 FIG. 4 is a schematic diagram of spacing detection according to another preferred embodiment of the present invention.

[0025] Fig.13 It is a three-dimensional perspective view of another preferred embodiment of the present invention.

[0026] Fig.14 FIG. 4 is a flow chart of steps of another preferred embodiment of the present invention.

[0027] Reference numerals:

[0028] Robotic Arm....1

[0029] Warp sensor....1 1

[0030] Distance sensor....1 2

[0031] Wafer storage mechanism....2

[0032] Image information code....2 1

[0033] Optical photography mechanism....3

[0034] Optical recognition module....4

[0035] Information code analysis unit....4 1

[0036] Object distance analysis unit....42

[0037] Wafer center analysis unit....43

[0038] Wafer....W

[0039] Vertical distance....x

[0040] Distance....y

[0041] Wafer distance....o DETAILED DESCRIPTION

[0042] In order to achieve the above-mentioned purpose and effect, the technical means and structures adopted by the present invention are described in detail with reference to the accompanying drawings for the features and functions of the preferred embodiments of the present invention so as to fully understand them.

[0043] See also Figures 1 to 6 As shown, it is a schematic diagram of the calculation of the three-dimensional perspective view to the center of a preferred embodiment of the present invention. It can be clearly seen from the figure that the present invention includes:

[0044] A robot arm 1 is taken as an example, which can be controlled by a computer and is used to place, pick up and move wafers;

[0045] The wafer storage mechanism 2 is provided on one side of the robot arm 1, and a storage device for storing wafers is used as an example;

[0046] The image information code 21 is provided on the wafer storage mechanism 2, and QR CODE is used as an example;

[0047] An optical photographing mechanism 3 is provided on the robot arm 1. The optical photographing mechanism 3 of this embodiment is a camera using a charge-coupled device (CCD);

[0048] An optical recognition module 4 connected to the optical photographing mechanism 3 and the robot arm 1, and a processor connected to the optical photographing mechanism 3 and receiving the photographed image is used as an example;

[0049] An information code analysis unit 41 disposed in the optical recognition module 4;

[0050] An object distance analysis unit 42 disposed in the optical recognition module 4; and

[0051] The wafer center analysis unit 43 is provided in the optical recognition module 4 . The information code analysis unit 41 , the object distance analysis unit 42 , and the wafer center analysis unit 43 of this embodiment are all based on the software in the optical recognition module 4 as an example.

[0052] Through the above description, the structure of the present technology can be understood, and according to the corresponding coordination of this structure, it can have the advantage of achieving fast and accurate correction action at a lower cost. The detailed explanation will be described below.

[0053] The automatic correction method of a robot arm of the present invention comprises the following steps:

[0054] (a) Image capture: using the optical photography mechanism 3 on the robot arm 1 to capture the image information code 21 on the wafer storage mechanism 2;

[0055] (b) First correction action: using the information code analysis unit 41 in the optical recognition module 4 to analyze the image information code 21 to obtain relevant position information, so that the robot arm 1 performs the first correction action;

[0056] (c) focusing the wafer: using the optical photography mechanism 3 to photograph and focus on the wafer in the wafer storage mechanism 2;

[0057] (d) Wafer distance calculation: using the object distance analysis unit 42 in the optical recognition module 4, the wafer distance between the optical photography mechanism 3 and the wafer is calculated through the focal length of the lens in the optical photography mechanism 3 and the distance between the lens and the photosensitive imaging position in the optical photography mechanism 3;

[0058] (e) Second correction action: After calculating the wafer distance, the wafer center analysis unit 43 calculates the distance between the robot arm 1 and the wafer center point through the distance between the robot arm 1 and the optical photography mechanism 3, the wafer distance, and the wafer width, to achieve the second correction action; and

[0059] (f) Wafer gripping: The distance between the robot arm 1 and the center point of the wafer is used to control the robot arm 1 to perform a wafer gripping action.

[0060] From the above steps, it can be known that the user can set the image information code 21 on the wafer storage mechanism 2 in advance, and when the robot arm 1 is to be used to clamp the wafer, a correction action must be performed first to accurately clamp the wafer in the wafer storage mechanism 2.

[0061] In this way, the optical photography mechanism 3 can be used to capture the image information code 21, and the image information code 21 can be analyzed by the information code analysis unit 41 in the optical recognition module 4 to obtain relevant position information (such as the relative direction of the wafer storage mechanism 2 to the robot arm 1), thereby performing the first correction action.

[0062] After the first correction, the approximate position of the wafer storage mechanism 2 can be determined, so that the optical camera mechanism 3 can be used to photograph the wafers in the wafer storage mechanism 2 and focus on the wafer to be taken out. At this time, the object distance analysis unit 42 can perform calculation and analysis through the thin lens imaging formula (1 / o+1 / i=1 / f), which is an existing mathematical formula.

[0063] The calculation method can be matched with Figure 5As shown, the distance between the lens in the optical photographic mechanism 3 and the focused object (wafer) is o, the distance between the lens in the optical photographic mechanism 3 and the photosensitive imaging position in the optical photographic mechanism 3 is i, and the focal length of the lens of the optical photographic mechanism 3 is f. The focal length (f) of the lens of the optical photographic mechanism 3 is a known data when the lens is installed or purchased, and the distance (i) between the lens in the optical photographic mechanism 3 and the photosensitive imaging position in the optical photographic mechanism 3 is the distance that can be known after focusing. In this way, the distance o between the lens in the optical photographic mechanism 3 and the focused object (wafer) can be calculated by the above formula. Since the lens is at the front end of the optical photographic mechanism 3, it can be directly used as the distance between the optical photographic mechanism 3 and the wafer, and is defined as the wafer distance o in this case.

[0064] After calculating the above wafer distance, Figure 6 As shown, since the optical photography mechanism 3 is directly installed on the upper side of the robot arm 1, the vertical distance x between the optical photography mechanism 3 and the robot arm 1 can be directly known. In this way, the wafer center analysis unit 43 can first calculate the wafer center by trigonometric function (x 2 +y 2 =o 2 ), calculate the distance y from the robot arm 1 to the edge of the wafer (i.e., the position point where the optical photography mechanism 3 focuses), and since the radius (d) of the wafer is known data before grabbing, but it is not limited, when the optical photography mechanism 3 captures the image information code 21 to obtain the relevant position information, the radius (d) of the wafer can be read and obtained at the same time, and transmitted to the wafer center analysis unit 43. In this way, the distance y from the robot arm 1 to the edge of the wafer is added to the radius (d) of the wafer, and the distance between the robot arm 1 and the center point of the wafer can be obtained, thereby achieving the second correction effect.

[0065] After two corrections, the robot arm 1 can automatically calculate the distance between the robot arm 1 and the center point of the wafer to perform the gripping action. The entire correction process can be completed by using the optical photography mechanism 3 in conjunction with the image information code 21 and then calculating through the optical recognition module 4. In this way, the cost saving effect can be achieved through a simple structure, and the entire action can be completed by only taking pictures and performing related calculations, which can also greatly improve the time and efficiency of correction.

[0066] Please also refer to Figures 7 to 9 As shown, it is a three-dimensional perspective view and a schematic diagram of warping detection of another preferred embodiment of the present invention. It can be clearly seen from the figure that this embodiment is similar to the above embodiment, only a warping sensor 11 is provided on the robot arm 1. The warping sensor 11 of this embodiment takes a laser sensor as an example.

[0067] The steps of this embodiment include:

[0068] (a) Image capture: using the optical photography mechanism on the robot arm 1 to capture the image information code on the wafer storage mechanism 2;

[0069] (b) First correction action: the image information code is analyzed by the information code analysis unit in the optical recognition module to obtain relevant position information, so that the robot arm 1 performs the first correction action;

[0070] (c) focusing the wafer: using an optical photography mechanism to photograph and focus on the wafer in the wafer storage mechanism 2;

[0071] (d) Wafer distance calculation: using the object distance analysis unit in the optical recognition module, the wafer distance between the optical photography mechanism and the wafer is calculated through the focal length of the lens in the optical photography mechanism and the distance between the lens and the photosensitive imaging position in the optical photography mechanism;

[0072] (e) Second correction action: After calculating the wafer distance, the wafer center analysis unit is used to calculate the distance between the robot arm 1 and the center point of the wafer through the distance between the robot arm 1 and the optical photography mechanism, the wafer distance, and the width of the wafer, so as to achieve the second correction action;

[0073] (f) Wafer gripping: using the distance between the robot arm 1 and the center point of the wafer to control the robot arm 1 to perform a wafer gripping action; and

[0074] (g) Warp detection: The warp sensor 11 on the robot arm 1 is used to detect the warp condition of the wafer.

[0075] As can be seen from the above embodiment, the distance from the robot arm 1 to the center of the wafer has been calculated. Based on this distance, it is only necessary to add the length of the radius of the last wafer W to roughly estimate the distance from the robot arm 1 to the bottom of the wafer storage mechanism 2. If the length measured after the laser emitted by the warp sensor 11 rebounds is less than the above distance, it can be determined that the wafer W has blocked the laser path of the warp sensor 11 due to the warping condition, thereby reducing the possibility of generating fragments due to touching the warped part when clamping the wafer W.

[0076] Please also refer to Figures 10 to 12 As shown, it is a three-dimensional perspective view and a schematic diagram of distance detection of another preferred embodiment of the present invention. It can be clearly seen from the figure that this embodiment is similar to the above embodiment, only a distance sensor 12 is provided on the robot arm 1. The distance sensor 12 of this embodiment takes a thin distance sensor as an example.

[0077] The steps of this embodiment include:

[0078] (a) Image capture: using the optical photography mechanism on the robot arm 1 to capture the image information code on the wafer storage mechanism;

[0079] (b) First correction action: The image information code is analyzed by the information code analysis unit in the optical recognition module to obtain relevant position information, so that the robot arm performs the first correction action;

[0080] (c) focusing the wafer: using an optical photography mechanism to photograph and focus on the wafer in the wafer storage mechanism 2;

[0081] (d) Wafer distance calculation: using the object distance analysis unit in the optical recognition module, the wafer distance between the optical photography mechanism and the wafer is calculated through the focal length of the lens in the optical photography mechanism and the distance between the lens and the photosensitive imaging position in the optical photography mechanism;

[0082] (e) Second correction action: After calculating the wafer distance, the wafer center analysis unit is used to calculate the distance between the robot arm 1 and the center point of the wafer through the distance between the robot arm and the optical photography mechanism, the wafer distance, and the width of the wafer, so as to achieve the second correction action;

[0083] (f) Wafer gripping: using the distance between the robot arm 1 and the center point of the wafer to control the robot arm 1 to perform a wafer gripping action; and

[0084] (g) Gap detection: The gap sensor 12 on the robot arm 1 is used to detect the gap between the wafer and the robot arm 1 .

[0085] When the robot arm 1 extends into the wafer storage mechanism 2 to perform a gripping action, the distance between the robot arm 1 and the upper and lower wafers W can be sensed by the distance sensor 12 to prevent collision due to too small a distance.

[0086] Please also refer to Fig.13 and Fig.14 , which is a three-dimensional perspective view and a step flow chart of another preferred embodiment of the present invention. It can be clearly seen from the figure that this embodiment is similar to the above embodiment, except that a spacing sensor 12 and a warping sensor 11 are provided on the robot arm 1 at the same time.

[0087] The steps of this embodiment include:

[0088] (a) Image capture: using the optical photography mechanism on the robot arm 1 to capture the image information code on the wafer storage mechanism;

[0089] (b) First correction action: the image information code is analyzed by the information code analysis unit in the optical recognition module to obtain relevant position information, so that the robot arm 1 performs the first correction action;

[0090] (c) focusing the wafer: using an optical camera mechanism to photograph and focus on the wafer in the wafer storage mechanism;

[0091] (d) Wafer distance calculation: using the object distance analysis unit in the optical recognition module, the wafer distance between the optical photography mechanism and the wafer is calculated through the focal length of the lens in the optical photography mechanism and the distance between the lens and the photosensitive imaging position in the optical photography mechanism;

[0092] (e) Second correction action: After calculating the wafer distance, the wafer center analysis unit is used to calculate the distance between the robot arm 1 and the center point of the wafer through the distance between the robot arm 1 and the optical photography mechanism, the wafer distance, and the width of the wafer, so as to achieve the second correction action;

[0093] (f) Wafer gripping: using the distance between the robot arm 1 and the center point of the wafer to control the robot arm 1 to perform a wafer gripping action; and

[0094] (g) Warp distance detection: The warp sensor 11 on the robot arm 1 is used to detect the warpage condition of the wafer, and the distance sensor 12 on the robot arm 1 is used to detect the distance between the wafer and the robot arm 1.

[0095] In this way, the robot arm 1 of the present invention can have the effects of warpage detection and spacing detection at the same time, indicating that the warpage sensor 11 and the spacing sensor 12 can be set at the same time to improve the safety of the present invention when in use.

[0096] However, the above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Therefore, all simple modifications and equivalent structural changes made by exemplifying the contents of the present invention's specification and drawings should be included in the patent scope of the present invention and stated.

Claims

1. A robot arm automatic correction device, characterized in that: Mainly include: Robotic arm; A wafer storage mechanism, wherein the wafer storage mechanism is arranged on one side of the robotic arm; An image information code, wherein the image information code is arranged on the wafer storage mechanism; An optical photographing mechanism, wherein the optical photographing mechanism is arranged on the mechanical arm; An optical recognition module, the optical recognition module information is connected to the optical photography mechanism and the mechanical arm; An information code analysis unit, which is disposed in the optical recognition module and can analyze the image information code to obtain relevant position information; an object distance analysis unit, the object distance analysis unit being arranged in the optical recognition module and being informationally connected to the information code analysis unit, the object distance analysis unit calculating the wafer distance between the optical photography mechanism and the wafer in the wafer storage mechanism through the focal length of the lens in the optical photography mechanism and the distance between the lens and the photosensitive imaging position in the optical photography mechanism; and The wafer center analysis unit is arranged in the optical recognition module and is connected to the information code analysis unit so as to calculate the distance between the robotic arm and the center point of the wafer through the distance between the robotic arm and the optical photography mechanism, the wafer distance, and the width of the wafer.

2. The automatic correction device for a robot arm according to claim 1, characterized in that: A warping sensor is provided on the mechanical arm.

3. The automatic correction device for a robot arm according to claim 1, characterized in that: The mechanical arm is provided with a spacing sensor.

4. The automatic correction device for a robot arm as claimed in claim 1, characterized in that: The object distance analysis unit performs calculation and analysis based on the thin lens imaging formula.

5. The automatic correction device for a robot arm as claimed in claim 1, characterized in that: The wafer center analysis unit calculates the distance between the robot arm and the wafer center point by using trigonometric function.

6. A method for automatic correction of a robot arm, characterized in that the steps include: (a) using the optical photography mechanism on the robot arm to photograph the image information code on the wafer storage mechanism; (b) using an information code analysis unit in the optical recognition module to analyze the image information code to obtain relevant position information, so that the robot arm performs a first correction action; (c) using the optical photography mechanism to photograph and focus on the wafer in the wafer storage mechanism; (d) using an object distance analysis unit in the optical recognition module to calculate the wafer distance between the optical photography mechanism and the wafer through the focal length of the lens in the optical photography mechanism and the distance between the lens and the photosensitive imaging position in the optical photography mechanism; (e) after calculating the wafer distance, the wafer center analysis unit is used to calculate the distance between the robotic arm and the wafer center point through the distance between the robotic arm and the optical photography mechanism, the wafer distance, and the wafer width, so as to achieve a second correction action; and (f) Using the distance between the robotic arm and the center point of the wafer, the robotic arm is controlled to perform a wafer clamping action.

7. The automatic correction method for a robot arm as claimed in claim 6, characterized in that: After step (f), step (g) is performed to detect the warping condition of the wafer using the warping sensor on the robotic arm.

8. The automatic correction method for a robot arm as claimed in claim 6, characterized in that: After step (f), step (g) is performed to detect the distance between the wafer and the robotic arm using a distance sensor on the robotic arm.

9. The automatic correction method for a robot arm as claimed in claim 6, characterized in that: The object distance analysis unit performs calculation and analysis based on the thin lens imaging formula.

10. The automatic correction method for a robot arm as claimed in claim 6, characterized in that: The wafer center analysis unit calculates the distance between the robot arm and the wafer center point by using trigonometric function.

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