Device for Judging the Execution Precision of Material Transmission Equipment

Abstract

The present invention relates to the technical field of semiconductor equipment, and provides a device for determining the execution accuracy of a material transfer device. By setting a positioning calibration table and a positioning calibration tool on the running section of an automatic material transfer device, driving the automatic material transfer device to be detected to execute the material grasping and placing action command, and detecting the actual height from the ground during the lowering process of the positioning calibration tool to generate an actual height change curve L1, which is superimposed on the measured standard height change curve L2, and intercepting the lowering height of the positioning calibration tool at the same time point for analysis, it is determined whether the automatic material transfer device to be detected meets the usage requirements. It realizes the unmanned accuracy detection of the automatic material transfer device and solves the problem that the execution accuracy of the existing material transfer device still requires manual re-inspection during detection.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor equipment, and in particular to an execution accuracy determination device for material transmission equipment in an automated material system. Background Art

[0002] In the process of semiconductor wafer production and manufacturing, in order to improve the factory's production efficiency, improve the wafer processing yield and the utilization rate of machine equipment, wafer factories generally introduce AMHS (Automatic Material Handling System) system to dispatch and transfer materials throughout the factory. OHT (Overhead Hoist Transfer) is a key component of AMHS. It is an automated material handling equipment that can travel on an aerial track. It drives the belt through a lifting motor to automatically grab the wafer transfer box FOUP (Front Open Unified Pod) set on the material loading machine, and quickly, stably and accurately transport materials within the wafer factory, so that wafers can be quickly and stably transported in various processing areas throughout the factory.

[0003] As the main transport subject in the AMHS system, OHT will undergo strict performance and accuracy verification before leaving the factory. However, after long-term operation, the execution accuracy of OHT may cause errors due to the wear of parts. When the error seriously affects the execution accuracy, OHT is difficult to dock with the ground machine during transportation. Therefore, in order to ensure that OHT can meet long-term high-precision operation, OHT needs to be regularly tested for accuracy health after long-term operation to ensure that its accuracy meets the health requirements for safe use; for OHT whose accuracy deviation has exceeded the allowable range, it needs to be readjusted. Usually, the accuracy detection of OHT adopts the method of visual positioning: the error of the X, Y and R axis deflection angle of OHT is verified based on the visual positioning system on the calibration fixture. However, in the actual test link, it is found that visual positioning will have false alarms due to various environmental factors, such as the stability of the test environment light, the cleanliness of the camera lens, the wear clarity of the positioning target or the camera shooting height. Therefore, when calibrating OHT, it is usually necessary to test multiple times to reduce the influence of interference factors. Summary of the invention

[0004] The purpose of the present invention is to provide an OHT execution accuracy determination device to solve the technical problem in the prior art that false alarms caused by too many influencing factors of camera system positioning detection require multiple manual re-inspections.

[0005] In one aspect, a device for determining execution accuracy of a material transmission device is provided, comprising:

[0006] Calibration table;

[0007] A calibration tool body is placed on the positioning surface of the calibration table for the automatic material transfer equipment to be detected to perform grasping and lowering actions, and the calibration table and the calibration tool body can be positioned and matched with each other;

[0008] A distance detection unit is installed on the calibration tool body for detecting the real-time continuous height change between the calibration tool body and the calibration table during the lowering process, and generating an actual ground clearance height change curve L1;

[0009] The main control unit in the calibration tool body superimposes the actual ground clearance height change curve L1 and the standard ground clearance height change curve L2 of the automatic material transfer equipment that meets the accuracy requirements measured in advance, and intercepts the same time point after aligning the time axes to calculate the height difference ΔL between the two at the corresponding time point;

[0010] The main control unit determines whether the execution accuracy of the automatic material transfer equipment fails according to whether ΔL exceeds the preset range: if ΔL does not exceed the preset, it means that the execution accuracy of the detected automatic material transfer equipment meets the usage requirements, otherwise it means that the execution accuracy error of the detected automatic material transfer equipment has exceeded the allowable range, and sends an alarm message to the upper computer for reminder.

[0011] Further, when the calibration tool body drops to the first preset height h1, the real-time continuous height change during the lowering process of the calibration tool body is started to be recorded, and the actual ground clearance height change curve L1 starts to be generated.

[0012] Further, the first preset height h1 is not less than the highest protrusion height set on the positioning surface of the calibration table.

[0013] Further, the standard ground clearance height change curve L2 is a smooth and continuous height change data curve measured when the automatic material transfer equipment that meets the accuracy requirements lowers the calibration tool body starting from the first preset height h1 until the calibration tool body is completely placed in a stable state.

[0014] Further, the inside of the calibration tool body is hollow and a perspective window is opened at the bottom, and at least a pair of positioning holes are provided at the bottom to complete the cooperation with the positioning pins at the top of the calibration table to position and fix the calibration tool body;

[0015] A vision camera is installed in the inner cavity of the calibration tool body. The vision camera can capture the positioning feature information at the top of the calibration table through the perspective window at the bottom of the calibration tool body to visually detect the execution accuracy during the lowering process of the calibration tool body;

[0016] The main control unit includes a first control module and a second control module. When the jig body descends to the first preset height h1 at the first speed V1, the first control module can control the vision camera to capture a picture at this position;

[0017] When the jig body descends to the second preset height h2, the second control module can control the jig body to descend at the second speed V2, and at the same time control the distance detection unit to start recording the continuous height change between the jig body and the calibration table in real time;

[0018] Wherein, the first speed V1 is greater than the second speed V2, and the second preset height h2 does not exceed the first preset height h1 and is not less than the height of the positioning pin protrusion;

[0019] A power module is further arranged in the inner cavity of the jig body to supply energy to all electrical devices and modules in the jig body.

[0020] Further, a joint part matching with the gripper part of the automatic material transmission device is arranged at the top of the jig body, and the joint part has the same top structure as the material W; not less than two of the positioning holes are circumferentially arrayed around the axis direction of the jig body.

[0021] Further, a positioning target is laid on the top surface of the calibration table. The positioning target is a regular geometric figure. The vision camera obtains the positioning coordinates by collecting the image of the positioning target, and calculates the relative position offset between the jig body and the calibration table according to the difference between the positioning coordinates on the positioning target and the preset central positioning coordinates of the vision camera.

[0022] Further, the distance detection unit includes a first detection module and a second detection module, which are respectively used to capture the first preset height h1 and the second preset height h2.

[0023] The embodiments of the present invention have at least the following technical effects:

[0024] 1. The detection method provided by the present invention is based on the work instruction program executed by the device under test in the standard working state. The first speed V1 and the second speed V2 mentioned above are speed parameters set based on the device under test executing a conventional operation command. Specifically, when placing the material W on the automatic material transfer device, usually two different speeds are set: the first speed V1 is used to quickly lower the material W, while the second speed V2 is used to slowly and precisely place the material W. Therefore, the first speed V1 and the second speed V2 do not need to be set manually additionally and can be directly applied to the detection process. When using this method to calibrate the automatic material transfer device, only need to drive the automatic material transfer device to be tested to the specified detection position and execute the conventional material picking and placing commands to complete the detection process; by analyzing whether the continuous height change curve of the calibration tool body matches the preset curve or whether the deviation is within the preset deviation range (when the accuracy of the automatic material transfer device fails, the calibration tool body will touch the convex part on the positioning calibration table during the descent process, affecting the continuous lowering height change value of the calibration tool body), so as to realize the detection of the execution accuracy of the automatic material transfer device and avoid the need for manual secondary re-inspection.

[0025] 2. The detection device provided by the present invention is specifically a detection device imitating the material W, which is internally equipped with independent communication, control, energy management modules, etc. The first preset height h1 and the second preset height h2 mentioned above can both be detected based on the detection device provided by the present invention itself, reducing the control difficulty of the device under test. Therefore, when detecting the execution accuracy of the automatic material transfer device, it can rely only on this device to complete the functions of sensing, collecting and feedback of its own physical quantities in the environment, complete data analysis through the operation processing module in this device, and timely feedback the result data to the upper computer or the handheld terminal for display. The detection personnel can directly obtain the final detection result at one time to avoid re-inspection. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to these drawings.

[0027] Figure 1 It is a schematic diagram of the working state of the automatic material transfer device;

[0028] Figure 2 It is a schematic diagram of the structure of the bottom of the material W and the bearing surface for bearing the material W;

[0029] Figure 3Schematic diagram for representing reference data of the detection state of the present invention;

[0030] Figure 4 Schematic structural diagram of the present invention in the detection state;

[0031] Figure 5 Schematic structural diagram of the present invention;

[0032] Figure 6 is Figure 4 frontal schematic structural diagram of;

[0033] Figure 7 is Figure 5 lateral schematic structural diagram of;

[0034] Figure 8 Schematic structural diagram of the present invention during detection;

[0035] Figure 9 Schematic structural diagram of the first mating state of the calibration tool body and the calibration table;

[0036] Figure 10 Schematic structural diagram of the second mating state of the calibration tool body and the calibration table;

[0037] Figure 11 Schematic structural diagram of the third mating state of the calibration tool body and the calibration table;

[0038] Figure 12 Schematic structural diagram of the top of the calibration table in the present invention;

[0039] Figure 13 Schematic structural diagram of the positioning pin in the present invention;

[0040] Figure 14 is Figure 13 local enlarged schematic structural diagram at position B in;

[0041] Figure 15 Logic diagram for judging the positioning accuracy in the present invention.

[0042] Icons: 1. Calibration tool body; 11. Joint part; 12. Top plate; 13. Support column; 14. Bottom plate; 141. Positioning hole; 2. Calibration table; 21. Table board; 22. Positioning pin installation groove; 23. Fixing hole; 24. Positioning target; 25. Positioning pin; 251. Top of the positioning pin; 252. Shoulder of the positioning pin; 253. Side wall of the positioning pin; 254. Positioning limit part of the positioning pin; 255. Installation part of the positioning pin; 3. Main control unit; 4. Power module; 5. Support frame; 6. First detection module; 7. Second detection module; 8. Vision camera; 9. Distance detection unit; W. Material. Detailed implementation manners

[0043] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work shall fall within the protection scope of the present invention.

[0044] Those skilled in the art of the present technology can understand that, unless otherwise defined, all terms used herein (including technical terms and scientific terms) have the same meaning as the general understanding of those of ordinary skill in the technical field to which the present invention belongs. It should also be understood that terms such as those defined in a general dictionary should be understood to have a meaning consistent with the meaning in the context of the prior art, and will not be interpreted with an idealized or overly formal meaning unless specifically defined as here.

[0045] Those skilled in the art of the present technology can understand that, unless specifically stated, the singular forms "a", "an", "" and "the" used herein may also include the plural forms. It should be further understood that the term "including" used in the specification of the present invention means the presence of features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or their combinations. The phrase "and / or" used herein includes all or any unit and all combinations of one or more of the associated listed items.

[0046] Please refer to Figure 1 and Figure 2 As shown, in order to increase the space utilization rate of the FAB (Fabrication integrated circuit production design) clean workshop in the AMHS automated material handling system, an overhead track is often laid below the workshop ceiling, and automated material handling equipment (such as OHT) is allowed to shuttle on the track to carry out the whole-factory handling of the material W in the workshop. Since the automated material handling equipment is suspended below the ceiling, the handling method of the material W mainly adopts an air-to-ground flexible docking. The lifting belt drives the gripper mechanism at the bottom to pick up, lift or lower the material W. This air-to-ground flexible docking operation under a large drop requires extremely high-precision positioning for cooperation to avoid the material W from being difficult to dock with the platform during picking and placing, resulting in dropping or tipping and damaging the material W. As Figure 2 shown in the content, although a guiding groove for cooperating with the docking platform is preset at the bottom of the existing material W, after the automatic material handling equipment has been running for a long time, error accumulation will occur and affect the final positioning accuracy. Especially when the accumulated error has exceeded the error correction range of the guiding groove, the material W may be lifted, tilted and slipped by the positioning pin on the docking platform during the picking and placing of the material W.

[0047] In one embodiment, the embodiment of the present invention provides a detection and determination device for the execution accuracy of a material transmission device, including: a calibration table 2;

[0048] First, the calibration table 2 is arranged on the running section of the automatic material transmission device, and a calibration tool body 1 is placed on the tabletop of the calibration table 2; wherein, the tabletop of the calibration table 2 is of the standard load-bearing tabletop specification for the material W and has standard positioning features, such as the setting angle and height of the positioning pins; the bottom of the calibration tool body 1 has positioning holes with the same features as the bottom of the material W.

[0049] Next, the automatic material transmission device to be detected is driven above the calibration table 2 and executes the material W grasping action command to grasp and lift the calibration tool body 1 placed above the calibration table 2, simulating the grasping of the material W.

[0050] Then, the automatic material transmission device under detection is driven to execute the material W lowering command, and the grasped calibration tool body 1 is stably placed at the initial position on the upper surface of the calibration table 2, and the actual ground clearance height of the calibration tool body 1 during the lowering process is detected in real time by the distance detection unit 9 to generate the actual ground clearance height change curve L1 of the calibration tool body 1.

[0051] Finally, the main control unit 3 superimposes the actual ground clearance height change curve L1 with the standard ground clearance height change curve L2 of the calibration tool body 1 measured by the automatic material transmission device under the standard accuracy, and intercepts the height difference at the same time point and records it as ΔL. The main control unit 3 determines whether the execution accuracy of the automatic material transmission device fails based on whether ΔL is within the preset allowable error range. If ΔL does not exceed, it means that the execution accuracy meets the usage requirements; otherwise, it means that the execution accuracy error of the detected automatic material transmission device has exceeded the allowable range and does not meet the usage requirements.

[0052] Specifically, reference can be made to Figure 3As shown: When the automatic material transfer equipment is operating, in order to increase the operation efficiency, the material W is usually placed at two speeds: before the second preset height h2, the material W is quickly lowered in order to reduce the total operation duration; when the material W reaches the second preset height h2, in order to maintain the stability of the material W during placement, the material W is slowly lowered, that is, when the automatic material transfer equipment is near the end position, the material W will be placed smoothly at another speed less than the initial placement speed. In the technical solution of the present invention, when the automatic material transfer equipment under standard precision picks and places the material W, the total operation duration is the same or within the allowable error duration without interference, that is, the total duration from the start of placing the material W until it is completely and smoothly placed by the automatic material transfer equipment that meets the precision requirements is the same or the duration difference is within the preset allowable error duration. Accordingly, under this condition, the ground clearance value of the material W at a certain moment within the range of t1 - t3 should conform to the predicted height value (the corresponding height value intercepted should be located within Figure 3 the shaded area in).

[0053] It should be explained here that the descending height positions of each automatic material transfer equipment that meets the precision requirements should be the same or the height difference is within the allowable error range at the same moment. When the descending height value of a certain automatic material transfer equipment exceeds the shaded area in the t2 - t3 stage, it indicates that an abnormality has occurred in the landing positioning of the automatic material transfer equipment. Among the variables that can affect the descending height of the material W in the scope of this test object is the execution precision of the automatic material transfer equipment. That is, when the abnormal automatic material transfer equipment places the material W, due to the resistance of the target position affecting the material W during the descending process, the smoothness of the material W's descent will be directly reduced, causing the material W not to be at the height position it should reach at a certain moment.

[0054] It is worth noting that in this implementation, the standard ground clearance change curve L2 is the change curve of the continuous real-time height data of the jig body 1 measured from the preset height h until the jig body 1 is completely and smoothly placed by the automatic material transfer equipment that meets the precision requirements; Figure 3The shaded area in it is the allowable error threshold range. The precision deviation within this error threshold range can be corrected through the positioning holes 141 at the bottom of the jig body 1. Therefore, the standard ground clearance height change curve L2 can be used as a reference standard for the execution precision of the automatic material transfer equipment to be detected. Under this standard, the automatic material transfer equipment to be detected is sequentially driven to carry and pick up the jig body 1, and the real-time continuous height change data of the automatic material transfer equipment during detection when placing the jig body 1 on the calibration table 2 is collected, and the actual ground clearance height change curve L1 is plotted and generated, and then superimposed curve fitting is performed with the standard ground clearance height change curve L2. The corresponding ground clearance height values of the standard ground clearance height change curve L2 and the actual ground clearance height change curve L1 at the same time point are intercepted for judgment, and multiple groups of time points can be taken for combined judgment to reduce errors. If the error value ΔL between the standard ground clearance height change curve L2 and the actual ground clearance height change curve L1 at a certain time point is within the allowable range (the height value of the actual ground clearance height change curve L1 is within Figure 3 the shaded range in it), it indicates that the execution precision of the automatic material transfer equipment during detection meets the requirements; if the error exceeds the allowable range, it indicates that the smoothness of the automatic material transfer equipment when placing the jig body 1 is affected, and the execution precision of the automatic material transfer equipment has failed. As mentioned above, the execution precision detection of the commonly used automatic material transfer equipment mainly relies on the vision positioning system, that is, the deviation between the positioning features captured by vision on the calibration table 2 and the execution positioning of the current jig body 1 is used to compare and analyze the XY coordinates of the automatic material transfer equipment to determine whether they match; while the detection method provided by the embodiment of this solution mainly judges the execution precision of the automatic material transfer equipment by detecting whether the jig body 1 reaches the calibrated Z-axis height at the calibrated time point, and by analyzing the continuous height change value of the Z-axis: if the positioning fails during the descent of the jig body 1, it will cause an abnormal fit between the positioning pin 25 of the calibration table 2 and the jig body 1, affecting the smoothness of the descent of the jig body 1. The positioning pin 25 will get stuck or abut against the bottom of the jig body 1, affecting the normal descent and causing an abnormal descent height of the Z-axis. Comparing with the standard ground clearance height change curve L2, a phenomenon that the height value between the jig body 1 and the calibration table 2 at the same time point does not conform to the calibrated height is generated to judge that the handling precision is abnormal. Through the execution precision detection method provided by this solution, it is possible to avoid the interference of environmental factors during precision detection, and directly judge the execution precision by whether the actually detected actual ground clearance height change curve L1 meets the preset requirements, avoiding repeated detection.

[0055] In another embodiment, please refer to Figure 4 、 Figure 8 and Figure 9As shown in the content, after the calibration tool body 1 descends to the first preset height h1, the actual height above the ground during the lowering process of the calibration tool body 1 begins to be detected in real time and recorded to generate the actual height change curve L1, so as to avoid the height detection module from running for a long time to collect data and occupy computing power, reduce the demand for the main controller's computing processing capabilities, and at the same time shorten the length of the curve comparison, and eliminate the invalid interference factors before the first preset height h1.

[0056] It should be noted that when the calibration tool body 1 is about to be placed on the calibration table 2, the dynamic changes in the actual cooperation process between the calibration tool body 1 and the calibration table 2 are used to make a final judgment on whether the final positioning accuracy result of the automatic material conveying equipment is invalid.

[0057] For details, please refer to Figure 2 , Figure 9 and Figure 10 The first preset height h1 for the detection trigger should not be less than the protruding height of the positioning pin 25 set on the calibration table 2; when the execution accuracy of the automatic material transmission equipment meets the use requirements, even if there is an error x1 between the matching parts of the calibration tool body 1 and the calibration table 2 (the positioning pin 25 deviates to the inner range of the positioning hole 141), the calibration tool body 1 and the positioning pin 25 can still smoothly transition and match under the slope correction of the positioning hole 141; please refer to Figure 11 As shown in the content, if the execution accuracy of the automatic material transmission equipment does not meet the use requirements, the positioning hole 141 at the bottom of the calibration tool body 1 and the matching part of the verification table 2 will produce a correction range deviation x2 beyond the positioning hole 141 (the positioning pin 25 is biased to the outer range of the positioning hole 141), and the top of the positioning pin 25 within this range will directly abut the outer side of the positioning hole 141, and the positioning pin 25 cannot smoothly match with the positioning hole 141. In this state, the positioning pin 25 will also collide with the bottom plate of the calibration tool body 1, hindering the normal fall of the calibration tool body 1, causing the height value of the actual ground height change curve L1 of the calibration tool body 1 and the standard ground height change curve L2 at the same time point to exceed the preset range. Therefore, the height change curve of the calibration tool body 1 is drawn only when the distance between the calibration tool body 1 and the verification table 2 reaches the critical h2, which is the preferred collection range for effectively detecting the execution accuracy of the automatic material transmission equipment, and the height change curve within this range is the actual detection comparison range.

[0058] In another embodiment, the interior of the calibration tool body 1 is a hollow structure, and a window for the vision camera (8) to capture images is provided in the bottom plate 14. At least one pair of positioning holes 141 for positioning are provided on the bottom plate 14 to cooperate with the positioning pins 25 on the top of the calibration table 2 for positioning and fixing the calibration tool body 1. When the calibration tool body 1 descends to align and cooperate with the calibration table 2, the positioning holes 141 at the bottom of the calibration tool body 1 need to be aligned with the positioning pins 25 before cooperation, that is, the execution accuracy of the automatic material transfer device can be judged by detecting the contact situation between the calibration tool body 1 and the calibration table 2 at this stage. It should be noted here that the maximum opening range of the positioning holes 141 does not exceed the maximum opening diameter of the positioning groove at the bottom of the material W. Further, it should be noted that the opening range of the positioning holes 141 should not be less than the maximum diameter of the positioning pins 25 and less than the maximum opening diameter of the positioning groove at the bottom of the material W. The main function of the calibration tool body 1 is to calibrate the execution accuracy of the automatic material handling device. If the opening range of the positioning holes 141 is larger than the opening range at the bottom of the material W, it means that the allowable deviation range of the calibration tool body 1 is larger than the correction range of the positioning groove at the bottom of the material W, which does not meet the detection requirements for the execution accuracy of the automatic material handling device. Similarly, setting the opening range of the positioning holes 141 to be smaller than the maximum opening diameter of the positioning groove at the bottom of the material W reduces the actual allowable deviation range of the calibration tool body 1, which can further improve the inspection accuracy and avoid the influence of errors.

[0059] Specifically, please refer to Figure 13 As shown, the positioning pins 25 provided in this embodiment include a positioning pin mounting portion 255 and a positioning pin side wall 253, and are installed in the slot holes on the table board 2 through the positioning pin limiting portion 254. There is a tip at the connecting portion between the top 251 of the positioning pin and the positioning pin side wall 253. It should be noted here that the positioning holes 141 themselves have a guiding function. When the positioning pin shoulder 252 is a chamfer or a fillet, it can assist in increasing the offset correction of the calibration tool body 1, and the actual positioning accuracy detection judgment result is directly affected by the secondary correction superposition between the two.

[0060] Specifically, please refer to Figure 12As shown, on the platen 21 at the top of the calibration table 2 provided in this embodiment, there is a positioning pin mounting groove 22 for mounting the positioning pins 25. The positioning pins 25 can slide on the positioning pins 25 and be fixed, so as to adapt to the distribution of the positioning holes 141 at the bottom of the calibration tool body 1 of different models. It should be noted here that there are also differences in the accuracy range requirements of the automatic material transfer equipment when handling materials W of different sizes. For example, there are differences between the positioning grooves at the bottoms of common 6-inch, 8-inch, and 12-inch FOUPs. When it is necessary to detect the handling devices for different handling targets, it is necessary to adjust the distance between the positioning pins 25 to simulate the center distance of the positioning grooves at the bottoms of different materials W. Therefore, in this embodiment, the specific distribution and arrangement of the positioning pins 25 can be adjusted adaptively to increase the applicable range of the calibration table 2.

[0061] In another embodiment, please refer to Figure 6 As shown in the content, the main control unit 3 includes a first control module, a second control module, and a central processor, and an FPGA digital signal processing chip is also built in the main control unit 3 to execute the curve matching algorithm mentioned above. When the calibration tool body 1 descends to the first preset height h1 at the first speed V1, the first control module can control the vision camera 8 to capture the picture; when the calibration tool body 1 descends to the second preset height h2, the second control module can control the calibration tool body 1 to descend at the second speed V2 and control the distance detection unit 9 to detect the relative height change between the calibration tool body 1 and the calibration table 2 in real time;

[0062] Among them, the first speed V1 is greater than the second speed V2, and the first preset height h1 is not less than the second preset height h2.

[0063] As mentioned above, since the automatic material transfer equipment not only needs to consider the total pick-and-place duration but also the stability of the material W when executing the material pick-and-place command, when the automatic material transfer equipment places the material W, it will first quickly lower the material W at the first speed V1, and then slowly lower it at the second speed V2 when the material W is approaching the bearing table surface, so that the material W can be placed smoothly; in this embodiment, a vision camera 8 is installed, and the vision camera 8 is a fixed-focus camera. Therefore, when taking pictures, a suitable focal length is required. At this focal length, the picture captured by the vision camera 8 is the clearest. If the shooting height does not meet the focal length requirements, the clarity of the captured picture will be greatly reduced, affecting the visual positioning judgment. Therefore, the preset height h1 in this embodiment is mainly set depending on the best focal length value of the vision camera 8. It should be noted that if the vision camera 8 uses a variable-focus camera, the preset height h1 can be any optimal height suitable for taking pictures.

[0064] Specifically, a joint part 11 that mates with the gripper of the automatic material transfer device is provided at the top of the jig body 1, and the top structure of the joint part 11 is the same as that of the material W. Three positioning holes 141 are provided at the bottom of the jig body 1, and the positioning holes 141 are circumferentially arrayed around the axis direction of the jig body 1. A positioning target 24 is laid on the top surface of the inspection table 2, where the positioning target 24 is a regular geometric figure. The vision camera 8 takes an image of the positioning target 24 from top to bottom, and after processing the image through the vision positioning system, extracts the positioning features on the captured image and converts them into digital coordinate values. The vision positioning system in the main control unit 3 relates the obtained positioning reference digital coordinates to the base coordinates of the vision camera 8, and after performing superposition calculation based on the difference between the positioning coordinate values on the positioning target 24 and the preset center positioning coordinates of the vision camera 8, the relative offset of XYR between the positioning hole 141 and the positioning pin 25 can be calculated through the coordinate difference. If the offset does not exceed the allowed offset range, it can be preliminarily indicated that the execution accuracy of the automatic material transfer device meets the application requirements. If the offset has exceeded, it can be preliminarily indicated that the execution accuracy of the automatic material transfer device has exceeded the allowed accuracy error.

[0065] It should be noted that in the determination program of vision inspection, the inspection is not carried out separately in a sealed or independent environment. Therefore, there are more interference factors in the vision positioning result in an open environment, such as different ambient lights inside the FAB and wear of the positioning target 24. So, regardless of whether the positioning accuracy meets the requirements, the preliminary judgment result obtained through the pure vision positioning system needs to undergo the detection step of the continuous height change curve proposed above for secondary judgment to reduce false alarms and false detections.

[0066] Specifically, the distance detection unit 9 includes a first detection module 6 and a second detection module 7. The first detection module 6 is used to capture a first preset height h1, and the second detection module 7 is used to capture the continuous height change after the jig body 1 reaches h2. By setting the first detection module 6 and the second detection module 7 to make judgments respectively, the difficulty of the control command of the later main control unit 3 is reduced. The trigger conditions of the first detection module 6 and the second detection module 7 can be set in the corresponding control code commands for application. Both the first detection module 6 and the second detection module 7 can be optical distance sensors. When the jig body 1 descends to the height of h1, the first detection module 6 sends a signal to the main control unit 3 to control the vision camera 8 to capture the positioning picture at the optimal height. Correspondingly, when the jig body 1 descends to the height of h2, the operation command of the data acquisition generation module is triggered, and the height change value of the second detection module 7 is collected in real time to generate a continuous height change curve of the jig body 1, that is, the actual ground clearance change curve L1. The actual ground clearance change curve L1 is curve-matched with the standard ground clearance change curve L2 through the FPGA digital signal processing chip in the main control unit 3. It should be noted here that in this embodiment, the acquisition modules are respectively set as the first detection module 6 and the second detection module 7. The purpose is to reduce the later control difficulty and the performance requirements for the central processing unit, and avoid the redundancy and conflict problems in the later control program. When a single acquisition module is set, the module is assigned no less than one acquisition task, and the corresponding results in this embodiment can also be achieved. However, a high-performance single acquisition module will not only increase the control difficulty and cost, but also generate a large amount of invalid data information for the real-time calculation of the central processor, and it is easy to generate data conflicts and cause error reporting phenomena.

[0067] In this embodiment, through the preliminary accuracy detection of the vision positioning system and the analysis of the accuracy based on the actual continuous height change curve L1 generated by uploading the real-time detection data of the second detection module 7 to the main control unit 3, a final judgment result is generated. It should be noted here that the execution accuracy determination device of the present invention is developed and transformed based on the jig in the existing vision detection scheme, and can be upgraded and used without changing the existing jig, that is, by setting a sensing device for collecting real-time height changes on the existing vision jig and directly applying it in combination with the detection method described above, avoiding the cost problem of secondary mold opening and processing.

[0068] Those of ordinary skill in the art can understand that to implement all or part of the processes in the above-described embodiment methods, it can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the above-described method embodiments. Among them, any reference to a memory, storage, database, or other medium used in the various embodiments provided in the present application can include at least one of non-volatile and volatile memories. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0069] Those skilled in the art of the present technology can understand that the steps, measures, and solutions in the various operations, methods, and processes discussed in the present invention can be alternated, changed, combined, or deleted. Further, other steps, measures, and solutions in the various operations, methods, and processes discussed in the present invention can also be alternated, changed, rearranged, decomposed, combined, or deleted. Further, the steps, measures, and solutions in the prior art that are the same as those disclosed in the various operations, methods, and processes in the present invention can also be alternated, changed, rearranged, decomposed, combined, or deleted.

[0070] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0071] The terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" can explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0072] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0073] In the description of this specification, the specific features, structures, materials, or characteristics can be combined in a suitable manner in any one or more embodiments or examples.

[0074] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for determining the execution accuracy of a material transmission device, characterized in that: include: A calibration table (2), a calibration tool body (1) is placed on the positioning surface of the calibration table (2), and is used for the automatic material transmission equipment to be tested to perform grabbing and lowering actions, and the calibration table (2) and the calibration tool body (1) can be positioned and matched; The calibration tool body (1) is provided with a distance detection unit (9) for detecting the real-time continuous height change between the calibration tool body (1) and the calibration platform (2) during the lowering process, and generating an actual height change curve L1 from the ground; The main control unit (3) in the calibration tool body (1) superimposes the actual ground clearance height change curve L1 with the pre-measured standard ground clearance height change curve L2 of automatic material transfer equipment that meets the accuracy requirements, aligns the time axis, intercepts the same time point and calculates the height difference ΔL between the two at the corresponding time point; The standard height change curve L2 is a smooth and continuous height change data curve measured when the automatic material transfer equipment that meets the accuracy requirements is placed under the calibration tool body (1) and is completely placed in a stable state; The main control unit (3) determines whether the execution accuracy of the automatic material conveying equipment is invalid according to whether ΔL exceeds a preset range: if ΔL does not exceed the preset range, it means that the execution accuracy of the automatic material conveying equipment being tested meets the use requirements; otherwise, it means that the execution accuracy error of the automatic material conveying equipment being tested has exceeded the allowable range, and sends an alarm message to the host computer for reminder.

2. The material transmission equipment execution accuracy determination device according to claim 1, characterized in that: When the calibration tool body (1) descends to a first preset height h1, the continuous height change of the calibration tool body (1) during the lowering process begins to be recorded in real time, and the actual height change curve L1 from the ground begins to be generated.

3. The material transmission equipment execution accuracy determination device according to claim 2, characterized in that: The first preset height h1 is not less than the highest protrusion height set on the positioning surface of the inspection table (2).

4. The material transmission equipment execution accuracy determination device according to claim 2, characterized in that: The calibration tool body (1) is hollow inside and has a perspective window at the bottom. At least one pair of positioning holes (141) is provided at the bottom to cooperate with the positioning pins (25) at the top of the calibration table (2) to position and fix the calibration tool body (1). A visual camera (8) is installed in the inner cavity of the calibration tool body (1), and the visual camera (8) can capture the positioning feature information of the top of the calibration platform (2) through a perspective window at the bottom of the calibration tool body (1), and perform visual inspection on the execution accuracy of the calibration tool body (1) during the descent process; The main control unit (3) comprises a first control module and a second control module. When the calibration tool body (1) descends to the first preset height h1 at a first speed V1, the first control module can control the visual camera (8) to capture images at this position; when the calibration tool body (1) descends to the second preset height h2, the second control module can control the calibration tool body to descend at a second speed V2, and at the same time control the distance detection unit (9) to start recording the continuous height change between the calibration tool body (1) and the calibration platform (2) in real time; Wherein, the first speed V1 is greater than the second speed V2, and the second preset height h2 is not greater than the first preset height h1 and is not less than the protruding height of the positioning pin (25); The inner cavity of the calibration tool body (1) is also provided with a power module (4) for supplying energy to all electrical equipment and modules in the calibration tool body (1).

5. The material transmission equipment execution accuracy determination device according to claim 4, characterized in that: The top of the calibration tool body (1) is provided with a coupling portion (11) that cooperates with a gripper portion of an automatic material transfer device, and the coupling portion (11) has the same structure as the top of the material (W); and the bottom is provided with no less than two positioning holes (141) arranged in a circular array around the axis of the calibration tool body (1).

6. The material transmission equipment execution accuracy determination device according to claim 4, characterized in that: The top surface of the calibration table (2) is paved with a positioning target (24), and the positioning target (24) is a regular geometric shape. The visual camera (8) obtains positioning coordinates by collecting an image of the positioning target (24), and calculates the relative position offset between the calibration fixture body (1) and the calibration table (2) based on the difference between the positioning coordinates on the positioning target (24) and the preset center positioning coordinates of the visual camera (8).

7. The material transmission equipment execution accuracy determination device according to claim 4, characterized in that: The distance detection unit (9) comprises a first detection module (6) and a second detection module (7), which are respectively used to capture the first preset height h1 and the second preset height h2.

Images