Device for judging execution precision of material conveying equipment

Abstract

The invention relates to the technical field of semiconductor equipment, and provides a device for judging the execution precision of material conveying equipment. Positioning calibration tables and positioning calibration tools are arranged on operation road sections of automatic material conveying equipment, the to-be-detected automatic material conveying equipment is driven to execute material grabbing and releasing action commands, the actual ground clearance of the positioning calibration tools in the releasing process is detected, and the actual ground clearance change curve L1 and the measured standard ground clearance change curve L2 are generated. And the descending heights of the positioning calibration tool at the same time point are superposed and intercepted for analysis, and whether the detected automatic material conveying equipment meets the use requirements or not is judged. The precision detection of the unmanned automatic material conveying equipment is realized, and the problem that manual reinspection is still needed when the execution precision of the existing material conveying equipment is detected is solved.

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, which is used for the automatic material transmission equipment to be tested to perform grabbing and lowering actions, and the calibration table and the calibration tool body can be positioned and matched;

[0008] The calibration tool body is provided with a distance detection unit for detecting the real-time continuous height change between the calibration tool body and the calibration platform during the lowering process, and generating an actual height change curve L1 from the ground;

[0009] The main control unit in the calibration tool body superimposes the actual ground height change curve L1 with the pre-measured standard ground height change curve L2 of the automatic material conveying 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;

[0010] The main control unit determines whether the execution accuracy of the automatic material conveying equipment is invalid based on whether ΔL exceeds the preset range: if the 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 an alarm message is sent to the host computer for reminder.

[0011] Furthermore, after the calibration tool body is lowered to the first preset height h1, the continuous height change of the calibration tool body during the lowering process starts to be recorded in real time, and the actual height change curve L1 from the ground starts to be generated.

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

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

[0014] Furthermore, the interior of the calibration tool body is hollow and a perspective window is provided at the bottom. At least a pair of positioning holes are provided at the bottom to cooperate with the positioning pins at the top of the calibration table to position and fix the calibration tool body.

[0015] A visual camera is installed in the inner cavity of the calibration tool body. The visual camera can capture the positioning feature information of the top of the calibration table through the perspective window at the bottom of the calibration tool body, and perform visual inspection on the execution accuracy of the calibration tool body during the descent process;

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

[0017] When the calibration tool body descends to a 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 to start recording the continuous height change between the calibration tool 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 is not greater than the first preset height h1 and is not less than the protruding height of the positioning pin;

[0019] The inner cavity of the school tool body is also provided with a power supply module to supply energy to all electrical devices and modules in the school tool body.

[0020] Furthermore, a coupling part cooperating with the gripper part of the automatic material conveying equipment is provided on the top of the calibration tool body, and the coupling part has the same structure as the top of the material W; and at least two positioning holes are arranged in a circular array around the axis direction of the calibration tool body.

[0021] Furthermore, a positioning target is laid on the top surface of the calibration table, and the positioning target is a regular geometric shape. The visual camera obtains the positioning coordinates by collecting the image of the positioning target, and calculates the relative position offset between the calibration fixture body and the calibration table according to the difference between the positioning coordinates on the positioning target and the preset center positioning coordinates of the visual camera.

[0022] Furthermore, 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 detected device under the standard working state. The first speed V1 and the second speed V2 mentioned above are speed parameters set by the detected device when executing the conventional operation command. Specifically, when the automatic material transmission device places the material W, two different speeds are usually set: the first speed V1 is used to quickly lower the material W, and the second speed V2 is used to slowly and accurately place the material W. Therefore, the first speed V1 and the second speed V2 do not need additional manual setting and can be directly applied to the detection process. When using this method to calibrate the automatic material transmission device, it is only necessary to drive the automatic material transmission device to be detected to the specified detection position and execute the conventional material pick-up and placement command 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 transmission device fails, the calibration tool body will touch the raised part on the positioning calibration platform during the descent process, affecting the continuous lowering height change value of the calibration tool body), the detection of the execution accuracy of the automatic material transmission device is realized, avoiding the need for manual secondary re-inspection.

[0025] 2. The detection device provided by the present invention is specifically a detection device for imitating material W, which is equipped with independent communication, control, energy management modules, etc. The first preset height h1 and the second preset height h2 mentioned above can be detected based on the detection device provided by the present invention, and the control difficulty of the detected equipment is reduced. Therefore, when performing precision detection on automatic material transmission equipment, it can only rely on this device to complete the perception, collection and feedback functions of its own physical quantities in the environment, complete data analysis through the calculation and processing module in this device, and promptly feedback the result data to the host computer or handheld terminal for display, so that the detection personnel can directly obtain the final detection results at one time to avoid re-inspection. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 It is a schematic diagram of the automatic material conveying equipment in working state;

[0028] Figure 2 It is a structural schematic diagram of the bottom of the material W and the bearing surface that bears the material W;

[0029] Figure 3A schematic diagram of the benchmark data for the detection status of the present invention;

[0030] Figure 4 This is a schematic diagram of the structure of the present invention when it is in a detection state;

[0031] Figure 5 It is a structural schematic diagram of the present invention;

[0032] Figure 6 for Figure 4 A schematic diagram of the structure in a front view;

[0033] Figure 7 for Figure 5 A side view schematic diagram of the structure;

[0034] Figure 8 It is a schematic diagram of the structure of the present invention during detection;

[0035] Fig. 9 It is a structural schematic diagram of the first matching state between the calibration fixture body and the calibration table;

[0036] Fig.10 It is a structural schematic diagram of the second matching state between the calibration fixture body and the calibration platform;

[0037] Fig.11 It is a schematic diagram of the third matching state of the calibration tool body and the calibration table;

[0038] Fig.12 It is a structural schematic diagram of the top of the inspection platform in the present invention;

[0039] Fig.13 It is a schematic diagram of the structure of the positioning pin in the present invention;

[0040] Fig.14 for Fig.13 A schematic diagram of the local enlarged structure at B in the middle;

[0041] Fig.15 This is a logic diagram for determining positioning accuracy in the present invention.

[0042] Icons: 1. Calibration tool body; 11. Joint; 12. Top plate; 13. Support column; 14. Bottom plate; 141. Positioning hole; 2. Calibration table; 21. Table; 22. Positioning pin mounting slot; 23. Fixing hole; 24. Positioning target; 25. Positioning pin; 251. Top of positioning pin; 252. Positioning pin shoulder; 253. Positioning pin side wall; 254. Positioning pin limiter; 255. Positioning pin mounting part; 3. Main control unit; 4. Power module; 5. Support frame; 6. First detection module; 7. Second detection module; 8. Visual camera; 9. Distance detection unit; W. Material. DETAILED DESCRIPTION

[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. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

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

[0045] Those skilled in the art will appreciate that, unless otherwise stated, the singular forms "a", "an", "" and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present invention refers to 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 combinations thereof. The term "and / or" used herein includes all or any unit and all combinations of one or more 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 room in the AMHS automated material handling system, an aerial track is often laid under the ceiling of the workshop, and automated material handling equipment (such as OHT) is allowed to shuttle on the track to transport the material W in the workshop throughout the factory. Since the automated material handling equipment is suspended under the ceiling, the material W is mainly transported by air-to-ground flexible docking, which uses a lifting belt to drive the bottom clamping mechanism to grab, lift or lower the material W. The air-to-ground flexible docking operation under such a large drop requires extremely high-precision positioning to cooperate, so as to prevent the material W from falling off or tipping over due to difficulty in docking with the platform during pick-up and placement, thereby damaging the material W. As Figure 2 As shown in the content, although the existing material W has a preset guide groove at the bottom to cooperate with the docking platform, when the automatic material handling equipment is operated for a long time, errors will accumulate and affect the final positioning accuracy. In particular, when the accumulated errors exceed the correctable error range of the guide groove, the material W may be lifted up, tilted, or slipped by the positioning pins on the docking platform when the material W is taken and placed.

[0047] In one embodiment, the present invention provides a device for detecting and determining the execution accuracy of a material transmission device, comprising: a calibration station 2;

[0048] First, the calibration table 2 is set in the running section of the automatic material conveying equipment, and the calibration tool body 1 is placed on the table of the calibration table 2; wherein, the table of the calibration table 2 is of standard material W bearing table specifications, 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 a positioning hole with the same features as the bottom of the material W;

[0049] Next, the automatic material conveying device to be inspected is driven to the top of the inspection table 2 and the material W grabbing action command is executed to grab and lift the calibration tool body 1 placed on the inspection table 2 to simulate the grabbing of the material W;

[0050] Then, the automatic material transmission device in the drive detection executes the material W lowering command, and the grabbed calibration tool body 1 is stably placed on the initial position of the upper surface of the calibration table 2, and the actual ground height of the calibration tool body 1 during the lowering process is detected in real time by the distance detection unit 9, and the actual ground height change curve L1 of the calibration tool body 1 is generated;

[0051] Finally, the main control unit 3 superimposes the actual ground height change curve L1 with the standard ground height change curve L2 of the measured pick-up and placement calibration fixture body 1 of the automatic material conveying equipment under standard accuracy, and intercepts the height difference at the same time point as ΔL. The main control unit 3 determines whether the execution accuracy of the automatic material conveying equipment is invalid based on whether ΔL is within the preset allowable error range. If ΔL is not exceeded, it means that the execution accuracy meets the use requirements. Otherwise, it means that the execution accuracy error of the detected automatic material conveying equipment has exceeded the allowable range and does not meet the use requirements.

[0052] For details, please refer to Figure 3As shown: When the automatic material conveying equipment is in operation, in order to increase the operating efficiency, the material W is usually placed at two speeds: before the second preset height h2, in order to reduce the total operating time, the material W will be quickly lowered; after the material W reaches the second preset height h2, in order to maintain the stability of the material W when placed, the material W will be slowly lowered, that is, when the automatic material conveying equipment is close to the end position, it will steadily place the material W at another speed that is less than the initial placement speed. In the technical scheme of this scheme, when the automatic material conveying equipment with standard accuracy is taking and placing the material W, the total operating time is the same or within the allowable error time in the absence of interference, that is, the total time taken by the automatic material conveying equipment that meets the accuracy requirements from the beginning of placing the material W to the complete and stable placement is the same or the time difference is within the preset allowable error time. Correspondingly, under this condition, the height value of the material W from the ground at a certain moment randomly selected within the range of t1-t3 should meet the predicted height value (the corresponding height value intercepted should be within Figure 3 within the shadow area).

[0053] It should be explained here that the descending height positions of all automatic material conveying equipment that meet the accuracy requirements at the same time should be the same or the height difference should be within the allowable error range. When the descending height value of one of the automatic material conveying equipment exceeds the shaded range during the t2-t3 stage, it means that the automatic material conveying equipment has an abnormality in the landing positioning. In the scope of this test object, the variable factor that can affect the descending height of material W is the execution accuracy of the automatic material conveying equipment, that is, when the abnormal automatic material conveying equipment places material W, because material W is affected by the resistance of the target position during the descent process, it will directly reduce the smoothness of the descent of material W, so that material W is not at the height position it should reach at a certain moment.

[0054] It is worth noting that the standard ground height change curve L2 in this embodiment is a continuous real-time height data change curve of the calibration tool body 1 measured from the preset height h when the automatic material transfer equipment that meets the accuracy requirements is placed until the calibration tool body 1 is completely placed in a stable state; Figure 3The shaded area in the figure is the allowable error threshold range. The accuracy deviation within this error threshold range can be corrected through the positioning hole 141 at the bottom of the calibration tool body 1. Therefore, the standard ground clearance height change curve L2 can be used as a reference mark for the execution accuracy of the automatic material conveying equipment to be tested; under this mark, the automatic material conveying equipment to be tested is driven in sequence to carry and place the calibration tool body 1, and the real-time continuous height change data of the automatic material conveying equipment under test when the calibration tool body 1 is placed on the calibration table 2 is collected, and the actual ground clearance height change curve L1 is drawn and generated, and the curve is superimposed and fitted with the standard ground clearance height change curve L2. The standard ground clearance height change curve L2 and the actual ground clearance height change curve L1 are intercepted and judged at the same time point. Multiple groups of time points can be combined for 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 between Figure 3 ), it means that the execution accuracy of the automatic material transfer equipment under test meets the requirements for use; if the error exceeds the allowed range, it means that the smoothness of the automatic material transfer equipment when placing the calibration tool body 1 is affected, and the execution accuracy of the automatic material transfer equipment has failed. As mentioned above, the execution accuracy detection of the automatic material transfer equipment commonly used now mainly relies on the visual positioning system, that is, by visually capturing the deviation between the positioning features on the calibration table 2 and the execution positioning of the current calibration tool body 1 to compare and analyze the XY coordinates of the automatic material transfer equipment to determine whether they are consistent; and the detection method provided in the embodiment of the present scheme mainly determines the execution accuracy of the automatic material transfer equipment by detecting whether the calibration tool body 1 reaches the calibrated Z-axis height at the calibration time point, and by analyzing the continuous height change value of the Z-axis: if the positioning fails during the descent of the calibration tool body 1, it will cause the coordination between the positioning pin 25 of the calibration table 2 and the calibration tool body 1 to be abnormal, so that the smoothness of the descent of the calibration tool body 1 is affected, and the positioning pin 25 will be stuck or against the bottom of the calibration tool body 1 to affect the normal descent, causing the Z-axis descent height to be abnormal. By comparing with the standard ground height change curve L2, the height value between the calibration tool body 1 and the calibration table 2 at the same time point does not meet the calibrated height, which is considered abnormal handling accuracy. The execution accuracy detection method provided by this solution can avoid environmental factors interfering with the detection during accuracy detection, and the execution accuracy can be judged directly by whether the actual ground height change curve L1 detected meets the preset, avoiding re-testing.

[0055] In another embodiment, please refer to Figure 4 , Figure 8 and Fig. 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 , Fig. 9 and Fig.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 Fig.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 is provided on the bottom plate 14 for the visual camera (8) to shoot the picture, and 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 to position and fix the calibration tool body 1; when the calibration tool body 1 is lowered to align 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 they can be matched, that is, by detecting the contact between the calibration tool body 1 and the calibration table 2 at this stage, the execution accuracy of the automatic material conveying equipment can be judged. It should be noted here that the maximum opening range of the positioning hole 141 does not exceed the maximum opening diameter of the positioning groove at the bottom of the material W, and it should be further noted that the opening range of the positioning hole 141 should not be less than the maximum diameter of the positioning pin 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 verify the execution accuracy of the automatic material handling device. If the opening range of the positioning hole 141 is larger than the opening range of 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, the opening range of the positioning hole 141 is set to be smaller than the maximum opening diameter of the positioning groove at the bottom of the material W, and the actual allowable deviation range of the calibration tool body 1 is reduced, which can further improve the inspection accuracy and avoid the influence of errors.

[0059] For details, please refer to Fig.13 As shown, the locating pin 25 provided in this embodiment includes a locating pin mounting portion 255 and a locating pin side wall 253, and is installed in a slot on the table 21 through a locating pin limiting portion 254, and there is a tip at the connection between the locating pin top 251 and the locating pin side wall 253; it should be noted here that the locating hole 141 itself has a guiding function. When the locating 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 secondary correction superposition between the two directly affects the actual positioning accuracy detection judgment result.

[0060] For details, please refer to Fig.12As shown, a positioning pin installation slot 22 for installing a positioning pin 25 is provided on the table 21 at the top of the calibration table 2 provided in this embodiment. The positioning pin 25 can slide and be fixed on the positioning pin 25 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 the accuracy range requirements of automatic material conveying equipment when transporting materials W of different sizes are also different. For example, there are differences between the positioning slots at the bottom of the common 6-inch, 8-inch, and 12-inch FOUPs. When it is necessary to detect the handling device of different handling targets, it is necessary to adjust the distance between the positioning pins 25 to simulate the center distance of the positioning slots at the bottom of different materials W. Therefore, in this embodiment, the specific distribution and arrangement of the positioning pins 25 can be adaptively adjusted to increase the scope of application 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 the main control unit 3 also has a built-in FPGA digital signal processing chip for executing the curve matching algorithm mentioned above. 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 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 a 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] 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, when the automatic material conveying equipment executes the material picking and placing command, it must not only consider the total picking and placing time but also the stability of the material W. Therefore, when the automatic material conveying equipment places the material W, it will first quickly lower the material W at a first speed V1, and when the material W is close to the load table, it will slowly lower it at a second speed V2, so that the material W can be placed stably. In this embodiment, a visual camera 8 is installed, wherein the visual camera 8 is a fixed-focus camera, so when taking pictures, a suitable focal length is required, and the picture that the visual camera 8 can capture at this focal length is the clearest. If the shooting height does not meet the focal length requirements, the clarity of the captured picture will be greatly reduced and affect the visual positioning judgment. Therefore, the preset height h1 in this embodiment is mainly set based on the optimal focal length value of the visual camera 8. It is worth noting that if the visual camera 8 adopts a variable-focus camera, the preset height h1 can be any optimal height suitable for taking pictures.

[0064] Specifically, the top of the calibration tool body 1 is provided with a coupling part 11 that cooperates with the gripper of the automatic material conveying equipment, and the coupling part 11 has the same top structure as the material W; three positioning holes 141 are provided at the bottom of the calibration tool body 1, and the positioning holes 141 are arranged in a circular array around the axial direction of the calibration tool body 1. A positioning target 24 is laid on the top surface of the verification table 2, wherein the positioning target 24 is a regular geometric shape. The visual camera 8 captures the image of the positioning target 24 from top to bottom, and extracts the positioning features on the captured image after processing the image through the visual positioning system and converts them into digital coordinate values. The visual positioning system in the main control unit 3 connects the basic coordinates of the visual camera 8 according to the obtained positioning reference digital coordinates, and after superimposing the difference between the positioning coordinate value on the positioning target 24 and the preset center positioning coordinate of the visual 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 allowable offset range, it can be preliminarily explained that the execution accuracy of the automatic material conveying equipment meets the application requirements. If the offset has exceeded, it can be preliminarily explained that the execution accuracy of the automatic material conveying equipment has exceeded the allowable accuracy error.

[0065] It is worth noting that in the visual detection judgment procedure, separate detection is not performed in a closed or independent environment. Therefore, there are more interference factors in the visual positioning results in an open environment, such as different ambient light inside the FAB, wear of the positioning target 24, etc. Therefore, regardless of whether the positioning accuracy is met, the preliminary judgment result made by the pure visual positioning system needs to be judged again by the detection step of the continuous height change curve mentioned above 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 the first preset height h1, and the second detection module 7 is used to capture the continuous height change after the calibration tool 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 main control unit 3 in the later stage is reduced, and the trigger conditions of the first detection module 6 and the second detection module 7 are respectively set in the corresponding control code command for application, wherein the first detection module 6 and the second detection module 7 can both be optical distance sensors. When the calibration tool body 1 drops to the height h1, the first detection module 6 sends a signal to the main control unit 3 to control the visual camera 8 to capture the positioning picture at the optimal height; accordingly, when the calibration tool body 1 drops to the height 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 calibration tool body 1, that is, the actual height change curve L1 from the ground, and the actual height change curve L1 from the ground is matched with the standard height change curve L2 from the ground through the FPGA digital signal processing chip in the main control unit 3; it should be noted here that the acquisition modules in this embodiment are respectively set as the first detection module 6 and the second detection module 7. The purpose is to reduce the difficulty of later control while reducing the performance requirements of the central processing unit and avoiding redundancy and conflict problems in the later control program. When a single acquisition module is set, the module is assigned with no less than one acquisition task, and the corresponding result in this embodiment can also be achieved, but the 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 real-time calculation of the central processing unit, which is easy to cause data conflicts and error reporting.

[0067] In this embodiment, the final judgment result is generated by analyzing the accuracy of 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 through preliminary accuracy detection of the visual positioning system. It is worth noting here that the execution accuracy determination device of the present invention is developed and modified based on the calibration tool in the existing visual detection scheme, and can be upgraded and used without changing the existing calibration tool, that is, by setting a sensor device for collecting real-time height changes on the existing visual calibration tool, and directly applying it in conjunction with the detection method mentioned above, the cost of secondary mold opening and processing is avoided.

[0068] It can be understood by a person of ordinary skill in the art that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing the relevant hardware through a computer program, and 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 embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include at least one of non-volatile and volatile memory. Non-volatile memory may include read-only memory (ROM), tape, floppy disk, flash memory or optical memory, etc. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0069] Those skilled in the art will appreciate that the various operations, methods, steps, measures, and schemes discussed in the present invention may be alternated, modified, combined, or deleted. Further, other steps, measures, and schemes in the various operations, methods, and schemes discussed in the present invention may also be alternated, modified, rearranged, decomposed, combined, or deleted. Further, the steps, measures, and schemes in the prior art that are similar to those disclosed in the present invention may also be alternated, modified, rearranged, decomposed, combined, or deleted.

[0070] In the description of the present invention, it is necessary to understand that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, and are 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 cannot be understood as a limitation on the present invention.

[0071] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0072] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific conditions.

[0073] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate 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 aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not cause the essence of the corresponding technical solutions to 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 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 1, characterized in that: The standard ground height change curve L2 is a smooth and continuous height change data curve measured by an automatic material transfer device that meets the accuracy requirements when the calibration tool body (1) is placed in a completely stable state.

5. 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 a second preset height h2, the second control module can control the calibration tool body (1) 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).

6. The material transmission equipment execution accuracy determination device according to claim 5, 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).

7. The material transmission equipment execution accuracy determination device according to claim 5, 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).

8. The material transmission equipment execution accuracy determination device according to claim 5, 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