Chip testing fixture adjusting system and adjusting method

Abstract

The application discloses a chip testing jig adjusting system and adjusting method, and relates to the technical field of chip testing.The adjusting system comprises a testing jig assembly, a visual identification module, a driving assembly and a control module.The first limiting piece and the second limiting piece of the testing jig assembly are slidingly matched in the limiting grooves of the base and form a limiting area.The visual identification module can obtain the chip width of the chip to be tested and the limiting width of the limiting area.The control module can control the driving assembly to drive the first limiting piece and the second limiting piece to slide relative to each other until the chip width and the limiting width meet the preset tolerance condition, and control the driving assembly to clamp the locking piece in the positioning groove aligned with each other between the base and the limiting piece to realize locking.The scheme is based on visual guidance and closed-loop feedback control, so that the size of the limiting area can be adaptively adjusted according to different specifications of the chip to be tested, and the locking is automatically realized after the adjustment, which can reduce the labor operation cost and realize the rapid adaptation of the testing jig.

Description

Technical Field

[0001] This application relates to the field of chip testing technology, and in particular to a chip testing fixture calibration system and calibration method. Background Technology

[0002] In the field of chip testing, especially in the testing of memory chips, it is necessary to use test fixtures to accurately position the chip under test in order to ensure reliable electrical contact between the probes and the pads.

[0003] Currently, chip testing fixtures generally adopt a fixed cavity structure, and one fixture can only accommodate one size of chip. When the specifications of the chip under test change, the entire fixture needs to be replaced manually. This operation method is not only slow in changing the type and affecting the testing efficiency, but also requires a dedicated testing fixture for each size of chip, resulting in an expansion of the types and quantities of fixtures, which in turn significantly increases the storage costs and management difficulty.

[0004] Therefore, how to achieve rapid adaptation of test fixtures to chips of multiple specifications while reducing manual operation costs has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] The main purpose of this application is to propose a chip test fixture calibration system and calibration method, which aims to reduce the cost of manual operation and at the same time realize the rapid adaptation of the chip test fixture to chips of multiple specifications.

[0006] To achieve the above objectives, the chip test fixture calibration system proposed in this application includes: The test fixture assembly includes a base, a first limiting member, a second limiting member, and a locking member. The base has a limiting groove and multiple first positioning grooves, which are arranged along the edge of the limiting groove. The first and second limiting members are slidably engaged in the limiting groove, forming a limiting area. The first and second limiting members move closer to or further away from each other during sliding to adjust the limiting width of the limiting area. Both the first and second limiting members have multiple second positioning grooves, which are opposite to the first positioning grooves in the mating direction. The mating direction intersects with or is perpendicular to the sliding direction of the first and second limiting members. A visual recognition module is used to acquire an image of the chip under test placed in the limiting area to obtain the chip width of the chip under test and the actual limiting width of the limiting area; A drive component is connected to the first limiting member, the second limiting member, and the locking device; The control module is electrically connected to the vision recognition module and the driving component; the control module is used to control the driving component to drive the first limiting member and the second limiting member to slide relative to each other until the chip width and the actual limiting width meet the preset tolerance condition; and the control module is used to control the driving component to engage the locking fastener in the mutually aligned first positioning groove and second positioning groove to restrict the sliding of the first limiting member and the second limiting member relative to the base.

[0007] In one embodiment, the limiting groove includes a first sidewall and a second sidewall disposed opposite to each other; The first limiting member includes a first main body and a plurality of first partition strips. The first main body slides along the first sidewall and is fitted into the limiting groove. The plurality of first partition strips are spaced apart on the first main body along the sliding direction of the first main body, and the first partition strips extend in a direction close to the second sidewall. The second limiting member includes a second main body and a plurality of second partition strips. The second main body slides along the second sidewall and is fitted into the limiting groove. The plurality of second partition strips are spaced apart on the second main body along the sliding direction of the second main body, and the second partition strips extend in a direction close to the first sidewall. Each pair of adjacent first partition strips and second partition strips forms a limiting area.

[0008] In one embodiment, the limiting groove is formed on the top surface of the base; the locking device includes a locking block and a threaded connector, the threaded connector being used to lock the locking block onto the base; The first positioning groove includes a plurality of first grooves, which are formed on the top of the first sidewall and spaced apart along the first sidewall; the second positioning groove includes a plurality of second grooves, which are formed on the top of the first main body and facing the first sidewall, and spaced apart along the sliding direction of the first main body; the locking block is used to insert into the aligned first and second grooves along the insertion direction, which is perpendicular to the sliding direction.

[0009] In one embodiment, the first positioning groove includes a plurality of third grooves, which are formed at the top of the second sidewall and spaced apart along the second sidewall; the second positioning groove includes a plurality of fourth grooves, which are formed at the top of the second main body and facing the second sidewall, and are spaced apart along the sliding direction of the second main body; the locking block is used to insert into the mutually aligned third and fourth grooves along the insertion direction, which is perpendicular to the sliding direction.

[0010] In one embodiment, when the locking block is inserted into the first and second grooves that are aligned with each other, the top surface of the locking block is higher than the top surface of the base and the top surface of the first main body.

[0011] In one embodiment, when the locking block is inserted into the mutually aligned third and fourth grooves, the top surface of the locking block is higher than the top surface of the base and the top surface of the second main body.

[0012] In one embodiment, the cross-sectional area of ​​the locking block gradually decreases from top to bottom.

[0013] In one embodiment, the cross-sectional area of ​​both the first tank and the second tank gradually decreases from top to bottom.

[0014] In one embodiment, the cross-sectional area of ​​the third tank and the cross-sectional area of ​​the fourth tank both gradually decrease from top to bottom.

[0015] In one embodiment, the plurality of sidewalls enclosing the limiting region have limiting wall surfaces and guide wall surfaces. The limiting wall surface is located between the bottom wall of the limiting groove and the guide wall surface. The limiting wall surface is perpendicular to the bottom wall of the limiting groove, and the guide wall surface gradually slopes outward along a direction perpendicular to the bottom wall of the limiting groove.

[0016] In one embodiment, the first limiting member is provided with at least two first waist-shaped holes at intervals, the first waist-shaped holes extending in a direction parallel to the limiting width; the bottom wall of the limiting groove is provided with at least two first guide posts at intervals, the first guide posts being correspondingly inserted and fitted into the first waist-shaped holes to restrict the first limiting member from sliding in a direction parallel to the limiting width.

[0017] In one embodiment, the second limiting member is provided with at least two second waist-shaped holes at intervals, the second waist-shaped holes extending in a direction parallel to the limiting width; the bottom wall of the limiting groove is provided with at least two second guide posts at intervals, the second guide posts being inserted into the second waist-shaped holes one by one to restrict the second limiting member from sliding in a direction parallel to the limiting width.

[0018] In one embodiment, each of the first positioning slots is provided with a corresponding chip size mark.

[0019] In one embodiment, both the first limiting member and the second limiting member are provided with positioning holes, which are used to dock with the driving end of the driving component.

[0020] This application also proposes a chip test fixture calibration method, implemented using the aforementioned chip test fixture calibration system; the calibration method includes the following steps: Place the chip under test in the limiting area; A detection image of the chip under test placed in the limiting area is acquired, and the chip width of the chip under test and the actual limiting width of the limiting area are obtained based on the detection image; Calculate the width error between the chip width and the actual limiting width; Determine whether the width error meets the preset tolerance condition; If the width error meets the preset tolerance condition, the drive component is controlled to engage the locking fastener in the first and second positioning slots that are aligned with each other, so as to restrict the sliding of the first and second limiting members relative to the base. If the width error does not meet the preset tolerance condition, the driving component is controlled to drive the first limiting member and the second limiting member to slide relative to each other to change the actual limiting width, and the process returns to the step of acquiring the detection image of the chip under test placed in the limiting area.

[0021] In one embodiment, after the step of ensuring the width error meets the preset tolerance condition, the following position calibration step is further included: The actual center position of the chip under test is obtained from the detected image. Calculate the positional error between the actual center position and the desired center position; If the position error exceeds the preset position tolerance, the position of the chip under test is adjusted by an external positioning mechanism, and the process returns to the step of acquiring the detection image of the chip under test placed in the limiting area. If the position error does not exceed the preset position tolerance, then the step of controlling the drive component to engage the locking fastener in the mutually aligned first and second positioning slots is executed.

[0022] In one embodiment, the step of obtaining the chip width of the chip under test and the actual limiting width of the limiting region based on the detection image includes: The detected image is preprocessed, including grayscale conversion and filtering. Edge detection is performed on the detection image after the preprocessing operation to extract the edge contour of the chip under test; Connectivity analysis is performed on the extracted edge contours to extract closed contours; An area filtering operation is performed on the closed contour to remove interfering contours with an area smaller than the minimum area threshold or an area larger than the maximum area threshold. The minimum bounding rectangle is calculated using the rotating caliper algorithm on the closed contour obtained by the area filtering operation, so as to obtain the center pixel coordinates, pixel width and pixel height of the minimum bounding rectangle; Using the camera calibration results, the center pixel coordinates and the pixel width are converted into physical coordinates and physical width in the world coordinate system, thereby obtaining the chip width and the actual limiting width.

[0023] In one embodiment, after the step of calculating the minimum bounding rectangle of the closed contour obtained by the area filtering operation using the rotating caliper algorithm, the method further includes: The rectangularity of the closed contour is calculated using the following formula: Ri =Ai / (wi hi) Where Ri is the rectangularity of the closed contour, Ai is the area of ​​the closed contour, wi is the pixel width of the minimum bounding rectangle, and hi is the pixel height of the minimum bounding rectangle; Only the closed contours whose rectangles are greater than a preset rectangle threshold are retained.

[0024] In one embodiment, the preset rectangularity threshold is 0.84 to 0.86.

[0025] In one embodiment, before the step of converting the center pixel coordinates and the pixel width into physical coordinates and physical width in the world coordinate system using the camera calibration results, the method further includes: Obtain the rotation angle θi of the minimum bounding rectangle, where the rotation angle θi is the angle between the long side of the minimum bounding rectangle and the u-axis of the image coordinate system, and the rotation angle θi satisfies: -90°≤θi≤0°; Determine whether the rotation angle θi exceeds the preset angle tolerance range; If the rotation angle θi exceeds the preset angle tolerance range, a position adjustment command is output to rotate the chip under test so that the long side of the chip under test is parallel to the length direction of the limiting area.

[0026] In one embodiment, in the step of controlling the driving component to drive the first limiting member and the second limiting member to slide relative to each other if the width error does not meet the preset tolerance condition, thereby changing the actual limiting width, and returning to the step of acquiring the detection image of the chip under test placed in the limiting area, the sliding adjustment amount δWn used during the nth return execution is: δWn=Kp γ^(n-1) ΔWn Where Kp is the initial gain coefficient, γ is the gain attenuation coefficient, 0 < γ < 1, ΔWn is the width error before the nth return execution, and n is the cumulative number of return executions.

[0027] In one embodiment, before each return to the step of acquiring a detection image of the chip under test placed in the limiting region, the following anti-vibration step is further included: Obtain the width error ΔWn before the current return execution, and the width errors ΔWn-1 and ΔWn-2 before the previous two return executions; A series of sign inversions is determined to have occurred if at least one of the following two conditions is met: ΔWn-2>0, and ΔWn-1<0, and ΔWn>0; ΔWn-2<0, and ΔWn-1>0, and ΔWn<0; Multiply the sliding adjustment amount δWn used in the nth return execution by the damping factor ζ to obtain the actual sliding adjustment amount for this return execution, where 0 < ζ < 1.

[0028] In the chip testing fixture calibration system and method proposed in this application, a slidable limiting area is formed by a first limiting member and a second limiting member that can slide relative to each other in a limiting groove. A visual recognition module acquires the chip width of the chip under test and the actual limiting width of the limiting area in real time. A control module then uses a closed-loop control mechanism based on the deviation between the chip width and the actual limiting width to drive the first and second limiting members to slide relative to each other, automatically matching the limiting width with the chip width. After matching, the drive module drives a locking device to lock the first and second limiting members, thus ensuring the limiting area is properly positioned. The limit width can be adaptively adjusted for different specifications, including chips of different widths, and automatically locked after adjustment. This enables rapid changeover of chip test fixtures in multi-specification production scenarios without the need for dedicated test fixtures for each chip specification. This reduces material costs, labor costs, and warehousing management pressure. It also eliminates positioning deviations introduced by manual operation in the measurement, judgment, and adjustment stages, improving the positioning accuracy and consistency of the limit width adjustment results. Thus, it enhances testing efficiency and reliability while ensuring chip testing reliability. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0030] Figure 1 This is a three-dimensional structural diagram of the test fixture assembly in one embodiment of the chip test fixture calibration system provided in this application; Figure 2 This is a schematic diagram of the assembly structure of the test fixture assembly in one embodiment of the chip test fixture calibration system provided in this application; Figure 3 An exploded view of an embodiment of the chip test fixture calibration system provided in this application; Figure 4 for Figure 3 Enlarged view of point A in the middle; Figure 5 A schematic diagram of module connections for an embodiment of the chip test fixture calibration system provided in this application; Figure 6 This is a flowchart illustrating an embodiment of the chip testing fixture calibration method provided in this application.

[0031] Explanation of icon numbers: 1. Test fixture assembly; 11. Base; 12. First limiting member; 13. Second limiting member; 14. Locking member; 15. Limiting area; 16. Second positioning groove; 17. First guide post; 18. Second guide post; 19. Positioning hole; 111. Limiting groove; 112. First positioning groove; 113. Chip size marking; 121. First main body; 122. First partition strip; 123. First oblong hole; 124. First pair of light slots; 131. Second main body; 132. Second partition strip; 133. Second oblong hole; 134. Second pair of light slots; 141. Locking block; 142. Threaded connector; 151. Limiting wall; 152. Guide wall; 161. Second groove; 162. Fourth groove; 1111, First sidewall; 1112, Second sidewall; 1121, First tank; 1122, Third tank; 2. Visual recognition module; 3. Drive components; 4. Control module; 5. Test machine.

[0032] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0033] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0034] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0035] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution that simultaneously satisfies A and B. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0036] In the field of chip testing, especially in the testing of memory chips, it is necessary to use test fixtures to accurately position the chip under test in order to ensure reliable electrical contact between the probes and the pads.

[0037] Currently, chip testing fixtures generally adopt a fixed cavity structure, and one fixture can only accommodate one size of chip. When the specifications of the chip under test change, the entire fixture needs to be replaced manually. This operation method is not only slow in changing the type and affecting the testing efficiency, but also requires a dedicated testing fixture for each size of chip, resulting in an expansion of the types and quantities of fixtures, which in turn significantly increases the storage costs and management difficulty.

[0038] To address the aforementioned issues, this application proposes a chip test fixture calibration system, which aims to reduce manual operation costs while enabling rapid adaptation of the chip test fixture to chips of various specifications.

[0039] Please see Figures 1 to 5 The chip test fixture calibration system includes: The test fixture assembly 1 includes a base 11, a first limiting member 12, a second limiting member 13, and a locking member 14. The base 11 is provided with a limiting groove 111 and a plurality of first positioning grooves 112, which are arranged at the edge of the limiting groove 111. The first limiting member 12 and the second limiting member 13 are slidably engaged in the limiting groove 111, and the first limiting member 12 and the second limiting member 13 enclose a limiting area 15. The first limiting member 12 and the second limiting member 13 move closer to each other or further away from each other during sliding to adjust the limiting width of the limiting area 15. The first limiting member 12 and the second limiting member 13 are each provided with a plurality of second positioning grooves 16, which are arranged opposite to the first positioning grooves 112 in the mating direction. This mating direction intersects with or is perpendicular to the sliding direction of the first limiting member 12 and the sliding direction of the second limiting member 13. The visual recognition module 2 is used to acquire an image of the chip under test (not shown in the figure) placed in the limiting area 15, so as to obtain the chip width of the chip under test and the actual limiting width of the limiting area 15. The drive component 3 is connected to the first limiting member 12, the second limiting member 13 and the locking member 14; The control module 4 is electrically connected to the vision recognition module 2 and the drive component 3. The control module 4 is used to control the drive component 3 to drive the first limiting member 12 and the second limiting member 13 to slide relative to each other until the chip width and the actual limiting width meet the preset tolerance conditions. The control module 4 is also used to control the drive component 3 to engage the locking member 14 in the first positioning groove 112 and the second positioning groove 16 that are aligned with each other, so as to restrict the sliding of the first limiting member 12 and the second limiting member 13 relative to the base 11.

[0040] In this embodiment, to facilitate the description of the positional relationships and movement directions between the components in the test fixture assembly 1, the following definitions are used: Figure 2 and Figure 3 The XYZ spatial coordinate system is shown. Specifically, the top surface of the base 11 is used as the reference plane. Within this reference plane, the sliding direction of the first limiting member 12 and the second limiting member 13 is defined as the Y direction, the direction perpendicular to the Y direction is defined as the X direction, and the direction perpendicular to the top surface of the base 11 is defined as the Z direction; wherein, the Y direction is also the adjustment direction of the limiting width. It should be noted that the X, Y, and Z directions here are only used to describe the relative position and motion relationship between the components and do not constitute a limitation on the placement posture of the test fixture assembly 1 in actual use. In subsequent embodiments, if the description of relative position and motion relationship is involved, this XYZ spatial coordinate system can be directly used and will not be repeated.

[0041] Based on this XYZ spatial coordinate system, the structure of the test fixture assembly 1 and the connection relationship of each component are described below.

[0042] The base 11 is a supporting component of the test fixture assembly 1. The base 11 can be mounted on the test platform 5 and is used to support the first limiting member 12 and the second limiting member 13. The base 11 can be made of metal material and manufactured by computer numerical control, such as aluminum alloy, to ensure structural strength while also meeting lightweight requirements. The base 11 has a generally flat structure, with a horizontal top surface and a limiting groove 111 formed thereon. The limiting groove 111 is a rectangular groove recessed downwards along the Z direction, extending along the Y direction, and includes a bottom wall and two opposing side walls.

[0043] The base 11 is also provided with a plurality of first positioning grooves 112; the plurality of first positioning grooves 112 are arranged on the edge of the limiting groove 111. Specifically, the plurality of first positioning grooves 112 can be provided on the top of one side wall of the limiting groove 111 and arranged at intervals along the Y direction, or they can be provided on the top of the other side wall of the limiting groove 111 and arranged at intervals along the Y direction, or they can be provided on the top of both side walls and arranged at intervals along the Y direction respectively. Each first positioning groove 112 occupies a certain position in the Y direction, which corresponds to a certain width specification of the chip under test, such as 7.5mm, 8mm, 9mm or 9.5mm, etc. The first positioning groove 112 can adopt a notch-shaped groove structure opened at the top corner of the side wall, and the opening of the notch-shaped groove opens to both the Z direction and the X direction.

[0044] The first limiting member 12 and the second limiting member 13 are both independent movable components, both disposed in the limiting groove 111 and slidably engaged with the limiting groove 111. Both the first limiting member 12 and the second limiting member 13 can slide relative to the base 11 along the Y direction. The first limiting member 12 and the second limiting member 13 each have a certain dimension in the X direction, and when the first limiting member 12 and the second limiting member 13 are projected onto the XZ plane along the Y direction, their projection areas include overlapping portions; the existence of this overlapping portion allows the first limiting member 12 and the second limiting member 13 to enclose and form a limiting region 15 when they move relative to each other along the Y direction, and the dimension of the limiting region 15 in the Y direction is the limiting width. Based on the above configuration, when the first limiting member 12 and the second limiting member 13 move towards each other in the Y direction, they move closer together, and the limiting width decreases; when the first limiting member 12 and the second limiting member 13 move away from each other in the Y direction, they move further apart, and the limiting width increases. Thus, by adjusting the positions of the first limiting member 12 and the second limiting member 13 in the Y direction, the limiting width can be adapted to test chips of different widths.

[0045] The first limiting member 12 and the second limiting member 13 are both provided with multiple second positioning grooves 16. The second positioning grooves 16 on the first limiting member 12 are located at the top of the first limiting member 12 and extend through to the side wall of the first limiting member 12, with the multiple second positioning grooves 16 spaced apart along the Y direction. The second positioning grooves 16 on the second limiting member 13 are located at the top of the second limiting member 13 and extend through to the side wall of the second limiting member 13, with the multiple second positioning grooves 16 spaced apart along the Y direction. The second positioning grooves 16 on the first limiting member 12 are positioned opposite to the first positioning grooves 112 on the base 11. When the first limiting member 12 slides to a preset position along the Y direction, one of the second positioning grooves 16 on the first limiting member 12 will align with one of the first positioning grooves 112 on the base 11 in the Y direction, forming a combined groove. Similarly, the second positioning groove 16 on the second limiting member 13 is positioned opposite to the first positioning groove 112 on the base 11. When the second limiting member 13 slides to a preset position along the Y direction, one of the second positioning grooves 16 on the second limiting member 13 will align with one of the first positioning grooves 112 on the base 11 in the Y direction, forming a combined groove. The second positioning groove 16 can adopt the same notch-shaped groove structure as the first positioning groove 112, that is, it is opened at the top corner of the limiting member, and its opening faces both the Z and X directions. In this way, when the first positioning groove 112 and the second positioning groove 16 are aligned in the Y direction, their openings face each other to form a continuous space into which the locking fastener 14 can be inserted.

[0046] The locking fastener 14 is used to fix the first limiting member 12 and the second limiting member 13 relative to the base 11 after they have been adjusted to the correct position. Specifically, when the first limiting member 12 slides along the Y direction to a certain preset position so that the currently formed limiting area 15 is suitable for accommodating the corresponding chip under test, a certain second positioning groove 16 on the first limiting member 12 will be aligned with a certain first positioning groove 112 on the base 11 in the Y direction. At this time, the two parts of the locking fastener 14 can be placed into the aligned first positioning groove 112 and second positioning groove 16 respectively. In this way, the limiting effect of the locking fastener 14 can prevent the first limiting member 12 from displacing relative to the base 11 in the Y direction. Similarly, when the second limiting member 13 slides along the Y direction to a preset position, making the currently formed limiting area 15 suitable for accommodating the corresponding chip under test, a second positioning groove 16 on the second limiting member 13 will align with a first positioning groove 112 on the base 11 in the Y direction. At this time, the two parts of the locking fastener 14 can be placed into the aligned first positioning groove 112 and second positioning groove 16 respectively. In this way, the limiting effect of the locking fastener 14 can prevent the second limiting member 13 from displacing relative to the base 11 in the Y direction. After the positions of the first limiting member 12 and the second limiting member 13 in the Y direction are fixed by the locking fastener 14, the limiting width of the limiting area 15 is locked at the current adjustment position, thereby forming a limiting effect on the chip under test accommodated in the limiting area 15. This ensures that the chip under test will not shift its position due to vibration or external force during subsequent testing, thus ensuring the reliability of electrical contact between the probe and the pads of the chip under test.

[0047] The visual recognition module 2 can be positioned above the test fixture assembly 1, with its image acquisition end facing the test fixture assembly 1, so that its field of view completely covers the limiting area 15. The visual recognition module 2 is used to acquire images of the chip under test placed in the limiting area 15, and to perform data processing and analysis on the acquired images. It can extract the dimensional information of the chip under test in the Y direction from the image, thereby obtaining the chip width. Simultaneously, the visual recognition module 2 can also extract the dimensional information of the limiting area 15 in the Y direction from the image, thereby obtaining the actual limiting width of the limiting area 15.

[0048] In one specific embodiment, the visual recognition module 2 includes an industrial camera, a lens, a light source assembly, and an image acquisition card. The industrial camera is mounted above the base 11, with its optical axis arranged along the Z-direction, and its field of view covering the limiting area 15. The light source assembly provides illumination for image acquisition, ensuring sufficient contrast in the image for the edges of the chip under test and the edges of the first limiting member 12 and the second limiting member 13. The light source assembly can be a ring-shaped LED light source, which surrounds the lens of the industrial camera, providing uniform diffuse illumination and preventing high-brightness reflections or shadows on the surface of the chip under test from affecting the accuracy of edge detection. The image acquisition card is electrically connected to the industrial camera and receives the image signals acquired by the industrial camera, converting them into digital image data that can be processed by the control module 4.

[0049] The drive assembly 3 is used to form a mechanical connection with the first limiting member 12, the second limiting member 13, and the locking member 14 respectively, and can provide driving force to the first limiting member 12, the second limiting member 13, and the locking member 14 under the control of the control module 4.

[0050] In one specific embodiment, the driving assembly 3 includes a first power unit for driving the first limiting member 12 to slide in the Y direction, a second power unit for driving the second limiting member 13 to slide in the Y direction, and a third power unit for driving the locking fastener 14. The first power unit may include a stepper motor and transmission mechanisms such as gears, racks, transmission chains, and synchronous belts. The driving end of the stepper motor can be connected to the first limiting member 12 via the transmission mechanism to drive the first limiting member 12 to slide in the limiting groove 111 in the Y direction. Similarly, the second power unit may include a stepper motor and transmission mechanisms such as gears, racks, transmission chains, and synchronous belts. The driving end of the stepper motor can be connected to the second limiting member 13 via the transmission mechanism to drive the second limiting member 13 to slide in the limiting groove 111 in the Y direction. The third power unit may employ a pneumatic gripper, which is used to grip the locking fastener 14 and place it in the aligned first positioning groove 112 and second positioning groove 16, or to remove the locking fastener 14 from the first positioning groove 112 and second positioning groove 16.

[0051] In another specific embodiment, the drive component 3 includes a robotic arm. The operating end of the robotic arm is set as a turntable structure, on which multiple different operating components are installed, such as grippers, push rods, screwdriver heads, etc. The robotic arm can switch between different operating components by rotating the turntable, so that a single robotic arm can sequentially perform all adjustment actions such as driving the first limit member 12 and the second limit member 13 to slide and picking up and placing the locking fastener 14. This can reduce the equipment footprint and equipment cost, and is suitable for testing scenarios with limited space.

[0052] In another specific embodiment, the driving component 3 includes a first robotic arm and a second robotic arm. The first robotic arm is used to perform the operation of picking up and placing the locking fastener 14, and the second robotic arm is used to drive the first limiting member 12 and the second limiting member 13 to slide along the Y direction. Through the division of labor and cooperation between the two robotic arms, the limiting width adjustment operation and the locking and fixing operation can be performed in parallel or alternately, saving the waiting time when the robotic arms change operating tools, thereby shortening the calibration cycle of the chip under test and improving testing efficiency.

[0053] It should be noted that the specific implementation methods of the driving component 3 listed above are merely examples. Those skilled in the art can combine or modify the above examples according to the needs of actual application scenarios. It is sufficient to ensure that the driving component 3 can drive the first limit member 12, the second limit member 13, and the locking device 14 to perform corresponding actions under the control of the control module 4.

[0054] The control module 4 can be a microcontroller unit (MCU) with functions such as data storage and retrieval, preset program execution, numerical calculation, and signal input / output. The control module 4 is electrically connected to the vision recognition module 2 and the drive component 3. The control module 4 receives detection data sent by the vision recognition module 2, which includes at least the chip width and the actual limit width. The control module 4 internally stores preset tolerance conditions, which are used to judge whether the current actual limit width matches the chip width to an acceptable degree. Specifically, the preset tolerance conditions can be limited by one or more specific numerical thresholds. For example, a tolerance value of 0.05mm can be set. When the absolute value of the difference between the chip width and the actual limit width is less than or equal to 0.05mm, the control module 4 determines that the preset tolerance conditions are met; when the absolute value of the difference between the chip width and the actual limit width is greater than 0.05mm, the control module 4 determines that the preset tolerance conditions are not met.

[0055] When the chip width and actual limit width measured by the visual recognition module 2 meet the preset tolerance conditions, the control module 4 sends a locking command to the drive assembly 3. After receiving the locking command, the drive assembly 3 drives the locking member 14 to engage with the first positioning groove 112 and the second positioning groove 16 that are currently aligned with each other. The locking member 14 can be fixed to the base 11 by means of threaded connection, riveting, snap-fit ​​connection, pin connection, etc. After the above operation is completed, the first limit member 12 and the second limit member 13 will be locked in the current adjustment position. At this time, the limit width of the limit area 15 will be fixed, and the adjustment process of the test fixture assembly 1 will end.

[0056] If the chip width currently measured by the visual recognition module 2 and the actual limit width do not meet the preset tolerance conditions, the control module 4 will calculate the sliding direction and displacement of the first limit member 12 and the second limit member 13 based on the width error between the two. Specifically, if the actual limit width is greater than the chip width, the control module 4 needs to calculate the displacement of the first limit member 12 and the second limit member 13 moving towards each other in the Y direction; if the actual limit width is less than the chip width, the control module 4 needs to calculate the displacement of the first limit member 12 and the second limit member 13 moving away from each other in the Y direction. The control module 4 can convert the calculated sliding direction and displacement into a drive command and send the drive command to the drive component 3; after receiving the drive command, the drive component 3 will drive the first limit member 12 and the second limit member 13 to slide relative to each other in the Y direction to change the actual limit width. After the driving component 3 completes the aforementioned sliding action, the control module 4 again obtains the adjusted actual limit width through the vision recognition module 2, and recalculates the width error between the actual limit width and the chip width to determine whether the width error meets the preset tolerance condition. If the recalculated width error still does not meet the preset tolerance condition, the control module 4 will generate a driving command again to drive the first limit member 12 and the second limit member 13 to slide relative to each other through the driving component 3. Then, it will obtain the new actual limit width through the vision recognition module 2 again and make a judgment again. The above adjustment process can be repeated until the control module 4 determines that the width error between the currently measured actual limit width and the chip width meets the preset tolerance condition. This feedback control process does not rely on manual observation and adjustment and can automatically complete the precise adjustment of the limit width.

[0057] Therefore, this embodiment forms an adjustable-width limiting region 15 by using a first limiting member 12 and a second limiting member 13 that can slide relative to each other in the limiting groove 111. The vision recognition module 2 obtains the chip width of the chip under test and the actual limiting width of the limiting region 15 in real time. Then, the control module 4 controls the drive component 3 to drive the first limiting member 12 and the second limiting member 13 to slide relative to each other based on the deviation between the chip width and the actual limiting width, so that the limiting width automatically matches the chip width. After the matching is completed, the drive component 3 drives the locking fastener 14 to lock the first limiting member 12 and the second limiting member 13. This solution, based on visual guidance and closed-loop feedback control, enables the limiting width of the limiting area 15 to adaptively adjust for different specifications, including chips of varying widths, and automatically locks after adjustment. This allows for rapid changeover of the chip testing fixture in multi-specification production scenarios without the need for dedicated testing fixtures for each chip specification. This reduces material and labor costs, as well as warehousing management pressure, keeping costs within the range of 300-500 yuan, a reduction of over 70% compared to traditional solutions. It also eliminates positioning deviations introduced by manual operation in the measurement, judgment, and adjustment stages, improving the positioning accuracy and consistency of the limiting width adjustment results. Thus, it enhances testing efficiency and reliability while ensuring chip testing reliability.

[0058] In one embodiment, refer to Figure 2 and Figure 3 The limiting groove 111 includes a first sidewall 1111 and a second sidewall 1112 that are disposed opposite to each other; The first limiting member 12 includes a first main body 121 and a plurality of first partition strips 122. The first main body 121 is slidably fitted in the limiting groove 111 along the first sidewall 1111. The plurality of first partition strips 122 are arranged at intervals on the first main body 121 along the sliding direction of the first main body 121, and the first partition strips 122 extend in the direction close to the second sidewall 1112. The second limiting member 13 includes a second main body 131 and a plurality of second partition strips 132. The second main body 131 is slidably fitted in the limiting groove 111 along the second sidewall 1112. The plurality of second partition strips 132 are arranged at intervals on the second main body 131 along the sliding direction of the second main body 131, and the second partition strips 132 extend in the direction close to the first sidewall 1111. A limiting area 15 is formed between each group of adjacent first partition strips 122 and second partition strips 132.

[0059] In this embodiment, the first limiting member 12 and the second limiting member 13 are further defined as comb-shaped structures to achieve parallel testing of multiple limiting regions 15.

[0060] Specifically, the limiting groove 111 includes a first sidewall 1111 and a second sidewall 1112 disposed opposite to each other in the X direction, and both the first sidewall 1111 and the second sidewall 1112 extend in the Y direction. The first limiting member 12 includes a first main body 121 and a plurality of first partition strips 122; the first main body 121 extends in the Y direction and is arranged close to the first sidewall 1111, and the first main body 121 can slide relative to the base 11 in the Y direction; one end of the first partition strip 122 is fixed to the first main body 121, and the other end extends in the X direction toward the second sidewall 1112, and the plurality of first partition strips 122 are spaced apart in the Y direction. The second limiting member 13 includes a second main body 131 and a plurality of second partition strips 132; the second main body 131 extends along the Y direction and is arranged close to the second side wall 1112, and the second main body 131 can slide relative to the base 11 along the Y direction; one end of the second partition strip 132 is fixed to the second main body 131 and the other end extends along the X direction toward the first side wall 1111, and the plurality of second partition strips 132 are arranged at intervals along the Y direction.

[0061] like Figure 2 and Figure 3 As shown, multiple first partition strips 122 and multiple second partition strips 132 are staggered in the Y direction. Each pair of adjacent first partition strips 122 and second partition strips 132 forms a rectangular limiting region 15. This limiting region 15 is formed by the first partition strips 122, second partition strips 132, first main stem 121, and second main stem 131. The dimension of this limiting region 15 in the Y direction is the limiting width. Each limiting region 15 is used to place one chip under test. When the first main stem 121 and the second main stem 131 slide relative to each other in the Y direction, all partition strips move synchronously with their respective main stems. This allows the limiting width of each limiting region 15 to change synchronously, thereby enabling synchronous adjustment of multiple limiting regions 15 to simultaneously accommodate multiple chips under test placed side by side.

[0062] It should be noted that the first main stem 121 and the plurality of first partition strips 122 can be integrally formed or separately configured; in the case of separate configuration, the plurality of first partition strips 122 can be connected to the first main stem 121 by a detachable connection or a non-detachable connection. Similarly, the second main stem 131 and the plurality of second partition strips 132 can be integrally formed or separately configured; in the case of separate configuration, the plurality of second partition strips 132 can be connected to the second main stem 131 by a detachable connection or a non-detachable connection.

[0063] In this embodiment, by setting multiple partition strips on the main body, the first limiting member 12 and the second limiting member 13 form a comb-like structure. During the sliding process, the first limiting member 12 and the second limiting member 13 can drive all the partition strips to move synchronously, thereby realizing the linkage adjustment of the limiting width of multiple limiting areas 15 and ensuring the consistency of the limiting width adjustment of each limiting area 15.

[0064] Furthermore, referring to Figure 2 and Figure 3 Each of the multiple first partition strips 122 is provided with a first pair of light grooves 124, which are arranged through the first limiting member 12 along the sliding direction. Specifically, the first pair of light grooves 124 extend through the multiple first partition strips 122 along the Y direction, thereby forming a groove extending through the first partition strip 122 along the Y direction. In actual operation, external detection light can pass through the grooves of the first pair of light grooves 124 corresponding to each of the first partition strips 122 in sequence to detect whether the placement angle of the first limiting member 12 is accurate.

[0065] Similarly, refer to Figure 2 and Figure 3 Each of the multiple second partition strips 132 is provided with a second pair of light grooves 134, which are arranged through the second limiting member 13 along its sliding direction. Specifically, the second pair of light grooves 134 extend through the multiple second partition strips 132 along the Y direction, thereby forming a groove extending through the second partition strip 132 along the Y direction. In actual operation, external detection light can sequentially pass through the grooves of the second pair of light grooves 134 corresponding to each of the second partition strips 132 to detect whether the placement angle of the second limiting member 13 is accurate.

[0066] As can be seen, by setting the first pair of light slots 124 and the second pair of light slots 134, a means is provided for the automated equipment to quickly verify the posture of the first limit member 12 and the second limit member 13. This allows the control module 4 to confirm in real time and quickly whether the first limit member 12 and the second limit member 13 are in the correct installation posture before starting the visual recognition operation and closed-loop adjustment, or during the visual recognition operation and closed-loop adjustment process. This ensures the accuracy of the chip width and actual limit width data obtained by the visual recognition module 2, thereby more effectively supporting the reliable execution of the visually guided limit width adaptive adjustment and automatic locking function in this application.

[0067] In one embodiment, refer to Figure 2 and Figure 3 The limiting groove 111 is formed on the top surface of the base 11; the locking component 14 includes a locking block 141 and a threaded connector 142, the threaded connector 142 being used to lock the locking block 141 onto the base 11. The first positioning groove 112 includes a plurality of first grooves 1121, which are formed on the top of the first sidewall 1111 and arranged at intervals along the first sidewall 1111; the second positioning groove 16 includes a plurality of second grooves 161, which are formed on the top of the first main body 121 and face the first sidewall 1111, and the plurality of second grooves 161 are arranged at intervals along the sliding direction of the first main body 121; the locking block 141 is used to insert into the first grooves 1121 and the second grooves 161 that are aligned with each other along the insertion direction, which is perpendicular to the sliding direction of the first limiting member 12 and the second limiting member 13.

[0068] In one embodiment, refer to Figure 2 and Figure 3 The first positioning groove 112 includes a plurality of third grooves 1122, which are opened at the top of the second side wall 1112 and arranged at intervals along the second side wall 1112; the second positioning groove 16 includes a plurality of fourth grooves 162, which are opened at the top of the second main body 131 and face the second side wall 1112, and are arranged at intervals along the sliding direction of the second main body 131; the locking block 141 is used to insert into the mutually aligned third grooves 1122 and fourth grooves 162 in the insertion direction, which is perpendicular to the sliding direction of the first limiting member 12 and the second limiting member 13.

[0069] Specifically, such as Figure 2 and Figure 3 As shown, multiple first grooves 1121 are formed on the top of the first sidewall 1111 and spaced apart along the Y direction, with the openings of the first grooves 1121 facing both the Z and X directions. Multiple second grooves 161 are formed on the top of the first main body 121 and spaced apart along the Y direction, with the openings of the second grooves 161 facing both the Z and X directions. When the first main body 121 slides along the Y direction to a preset position, one of the first grooves 1121 will align with the corresponding second groove 161 in the Y direction to form a closed-loop groove structure. At this time, a locking block 141 can be driven by the driving component 3 to simultaneously insert and engage with the aligned first groove 1121 and second groove 161 from top to bottom, thereby locking the first main body 121 relative to the base 11 in the Y direction.

[0070] Similarly, as Figure 2 and Figure 3As shown, multiple third grooves 1122 are formed on the top of the second sidewall 1112 and spaced apart along the Y direction, with the openings of the third grooves 1122 facing both the Z and X directions. Multiple fourth grooves 162 are formed on the top of the second main body 131 and spaced apart along the Y direction, with the openings of the fourth grooves 162 facing both the Z and X directions. When the second main body 131 slides along the Y direction to a preset position, one of the third grooves 1122 will align with the corresponding fourth groove 162 in the Y direction to form a closed-loop groove structure. At this time, the driving component 3 can drive another locking block 141 to simultaneously insert and engage with the aligned third groove 1122 and fourth groove 162 from top to bottom, thereby locking the second main body 131 relative to the base 11 in the Y direction.

[0071] Based on the above structure, the locking block 141 can simultaneously occupy the positioning groove on the base 11 and the positioning groove on the limiting member, thereby preventing the limiting member from sliding relative to the base 11 in the Y direction. Then, the locking block 141, after being engaged, is locked onto the base 11 by a threaded connector 142 such as a bolt to maintain its fixation. This locking method has a simple structure and is easy to operate, achieving reliable limiting and locking between the first limiting member 12, the second limiting member 13, and the base 11 without the need for a complex locking mechanism.

[0072] In one embodiment, refer to Figure 2 and Figure 3 When the locking block 141 is inserted into the first groove 1121 and the second groove 161 that are aligned with each other, the top surface of the locking block 141 is higher than the top surface of the base 11 and the top surface of the first main body 121.

[0073] In one embodiment, refer to Figure 2 and Figure 3 When the locking block 141 is inserted into the third groove 1122 and the fourth groove 162 that are aligned with each other, the top surface of the locking block 141 is higher than the top surface of the base 11 and the top surface of the second main body 131.

[0074] Specifically, by setting the height of the locking block 141 to be greater than the depth of the positioning groove, when the locking block 141 is inserted into the aligned first groove 1121 and second groove 161, the top surface of the locking block 141 is higher than the top surface of the base 11 and the top surface of the first main body 121. Similarly, when the locking block 141 is inserted into the aligned third groove 1122 and fourth groove 162, the top surface of the locking block 141 is higher than the top surface of the base 11 and the top surface of the second main body 131. This allows the top of the locking block 141 to protrude from the top surface of the base 11, the top surface of the first limiting member 12, and the top surface of the second limiting member 13. This protruding portion can be gripped by the clamping mechanism in the drive assembly 3, thereby facilitating the picking, placing, and transferring of the locking block 141 during automated operation.

[0075] In one embodiment, refer to Figure 2 and Figure 3 The cross-sectional area of ​​the locking block 141 gradually decreases from top to bottom, resulting in a tapered structure that is larger at the top and smaller at the bottom. When the locking block 141 is inserted into the corresponding positioning groove from top to bottom, the smaller cross-sectional area of ​​the lower part of the locking block 141 ensures that it can smoothly enter the positioning groove without easily getting stuck. As the locking block 141 continues to move downward, the upper part of the locking block 141 with a larger cross-sectional area will gradually form a contact fit with the groove wall of the positioning groove.

[0076] In one embodiment, refer to Figure 2 and Figure 3 The cross-sectional area of ​​the first tank 1121 and the cross-sectional area of ​​the second tank 161 both gradually decrease from top to bottom.

[0077] In one embodiment, refer to Figure 2 and Figure 3 The cross-sectional area of ​​the third tank 1122 and the cross-sectional area of ​​the fourth tank 162 both gradually decrease from top to bottom.

[0078] Specifically, when the cross-sectional area of ​​the first groove 1121 gradually decreases from top to bottom, and the cross-sectional area of ​​the second groove 161 gradually decreases from top to bottom, both the first groove 1121 and the second groove 161 have a conical groove structure that is larger at the top and smaller at the bottom. Similarly, when the cross-sectional area of ​​the third groove 1122 gradually decreases from top to bottom, and the cross-sectional area of ​​the fourth groove 162 gradually decreases from top to bottom, both the third groove 1122 and the fourth groove 162 have a conical groove structure that is larger at the top and smaller at the bottom.

[0079] When the cross-sectional area of ​​the locking block 141 gradually decreases from top to bottom, and the cross-sectional area of ​​each groove also gradually decreases from top to bottom, the outer wall of the locking block 141 and the inner wall of each groove can form a mutually mating conical structure. When the locking block 141 is inserted into the corresponding groove, during the process of tightening the locking block 141 downwards through the threaded connector 142, the conical surface of the locking block 141 and the conical surface of the groove gradually press together to produce a wedging effect. This wedge action can eliminate the gap between the locking block 141 and the positioning groove, improving the positioning accuracy after locking. On the other hand, the oblique component force generated by the conical surface pressing can exert a downward force on the first limiting member 12 and the second limiting member 13, thereby pressing and fixing the first limiting member 12 and the second limiting member 13 in the limiting groove 111. At this time, the locking block 141 can not only block the sliding of the first limiting member 12 and the second limiting member 13 relative to the base 11 in the Y direction, but also restrict the movement of the first limiting member 12 and the second limiting member 13 in the X and Z directions through the downward pressing force, thereby improving the positional stability of the first limiting member 12 and the second limiting member 13 in the subsequent testing process.

[0080] In one embodiment, refer to Figures 2 to 4 The multiple sidewalls that enclose and form the limiting area 15 have limiting wall surface 151 and guide wall surface 152. The limiting wall surface 151 is located between the bottom wall of the limiting groove 111 and the guide wall surface 152. The limiting wall surface 151 is perpendicular to the bottom wall of the limiting groove 111. The guide wall surface 152 gradually tilts outward along the direction perpendicular to the bottom wall of the limiting groove 111.

[0081] Specifically, when the first limiting member 12 and the second limiting member 13 are configured as follows: Figure 2 and Figure 3 In the comb-like structure shown, the limiting area 15 is formed by the first partition strip 122, the second partition strip 132, the first main stem 121, and the second main stem 131. At this time, as... Figure 4As shown, the sidewalls of the first partition strip 122, the second partition strip 132, the first main stem 121, and the second main stem 131 facing the limiting area 15 can all be configured to include a limiting wall 151 and a guide wall 152 connected in sequence. The limiting wall 151 is located below the guide wall 152 and is perpendicular to the XY plane. The guide wall 152 gradually slopes outward along the positive Z-axis, so that the cross-sectional dimension of the top opening of the limiting area 15 is larger than the cross-sectional dimension of its bottom. When the chip under test is placed downward along the Z-direction into the limiting area 15, the guide wall 152 can guide the chip under test. Even if there is a slight deviation in the initial placement position of the chip under test in the X or Y direction, the chip under test can slide into the bottom of the limiting area 15 along the guide wall 152, thereby reducing the positioning accuracy requirements during the chip under test placement and removal process, and reducing scratch damage caused by direct collision between the edge of the chip under test and the sidewall. Once the chip under test (DUT) is placed in the limiting area 15, the limiting wall 151 can limit the DUT to prevent it from shifting significantly in the XY plane during subsequent testing. A gap of 0.08~0.12mm exists between the limiting wall 151 and the corresponding side of the DUT. This avoids adverse effects on the electrical connection of the DUT due to an excessively large gap, while also preventing the DUT from jamming due to an excessively small gap. Preferably, this gap is set to 0.1mm.

[0082] In one embodiment, a 30° chamfer is formed between the guide wall 152 and the limiting wall 151. This 30° chamfer makes the cross-sectional dimension of the top opening of the limiting area 15 larger than its bottom cross-sectional dimension. When the chip under test (DUT) is placed downwards into the limiting area 15 along the Z direction, the 30° chamfer guides the DUT. Even if there is a slight deviation in the initial placement position of the DUT in the X or Y direction, the DUT can slide along the guide wall 152 into the bottom of the limiting area 15, thereby reducing the positioning accuracy requirements during the placement and removal of the DUT and reducing scratch damage caused by direct collision between the edge of the DUT and the sidewall. After the DUT is placed, the limiting wall 151 limits the DUT. A non-contact gap of 0.10mm to 0.15mm is maintained between the limiting wall 151 and the corresponding side of the DUT. This avoids adverse effects on the electrical connection of the DUT due to an excessively large gap, and also avoids jamming of the DUT due to an excessively small gap.

[0083] In one embodiment, refer to Figure 2 and Figure 3The first limiting member 12 is provided with at least two first waist-shaped holes 123 at intervals, and the first waist-shaped holes 123 extend in a direction parallel to the limiting width; the bottom wall of the limiting groove 111 is provided with at least two first guide posts 17 at intervals, and the first guide posts 17 are correspondingly inserted and fitted in the first waist-shaped holes 123 to restrict the first limiting member 12 from sliding in a direction parallel to the limiting width.

[0084] In one embodiment, refer to Figure 2 and Figure 3 The second limiting member 13 is provided with at least two second waist-shaped holes 133 at intervals, and the second waist-shaped holes 133 extend in a direction parallel to the limiting width; the bottom wall of the limiting groove 111 is provided with at least two second guide posts 18 at intervals, and the second guide posts 18 are correspondingly inserted and fitted in the second waist-shaped holes 133 to restrict the second limiting member 13 from sliding in a direction parallel to the limiting width.

[0085] Specifically, the first limiting member 12 is provided with at least two first waist-shaped holes 123 spaced apart along the Y direction. The long axis of the first waist-shaped holes 123 extends along the Y direction, and the first waist-shaped holes 123 penetrate the first limiting member 12 along the Z direction. The bottom wall of the limiting groove 111 is provided with at least two first guide posts 17 spaced apart along the Y direction. The axis of the first guide post 17 extends along the Z direction, and each first guide post 17 is correspondingly fitted into each first waist-shaped hole 123. Since the width of the first waist-shaped hole 123 in the X direction is adapted to the diameter of the first guide post 17, the first guide post 17 allows the first limiting member 12 to slide along the Y direction, while constraining the displacement of the first limiting member 12 in the X direction. The first limiting member 12 can also avoid deflection during the sliding process of the first limiting member 12 by the joint limiting effect of the two first guide posts 17.

[0086] Similarly, at least two second oblong holes 133 are spaced apart along the Y direction on the second limiting member 13. The long axis of the second oblong holes 133 extends along the Y direction, and the second oblong holes 133 penetrate the second limiting member 13 along the Z direction. At least two second guide posts 18 are spaced apart along the Y direction on the bottom wall of the limiting groove 111. The axis of the second guide posts 18 extends along the Z direction, and each second guide post 18 is correspondingly fitted into each second oblong hole 133. Since the width of the second oblong hole 133 in the X direction is adapted to the diameter of the second guide post 18, the second guide post 18 allows the second limiting member 13 to slide along the Y direction, while restraining the displacement of the second limiting member 13 in the X direction. The common limiting effect of the two second guide posts 18 can prevent the second limiting member 13 from deflecting during the sliding process along the Y direction.

[0087] Based on the guiding cooperation between the guide post and the waist-shaped hole, it can be ensured that the first limiting member 12 and the second limiting member 13 always maintain a movement trajectory parallel to the Y direction during the sliding process, avoiding the problem of inconsistent limiting width at different positions in the Y direction due to positional deviation.

[0088] In one embodiment, refer to Figure 2 and Figure 3 Each first positioning groove 112 is provided with a corresponding chip size mark 113. This chip size mark 113 can be a number or symbol mark located on the top surface of the base 11 and beside the first positioning groove 112, used to indicate the limiting width value corresponding to that first positioning groove 112. Specifically, as shown... Figure 2 and Figure 3 As shown, 7.5 can be marked on the side of the first positioning groove 112 corresponding to a 7.5mm limit width, and 8 can be marked on the side of the first positioning groove 112 corresponding to an 8mm limit width, and so on.

[0089] In actual operation, the visual recognition module 2 can read the chip size identifier 113 during the image acquisition process through the character recognition function, and send the width value indicated by the chip size identifier 113 to the control module 4. The control module 4 can use the width value as a reference value for the target limit width and compare and verify it with the chip width detected by the visual recognition module 2.

[0090] In one embodiment, refer to Figure 2 and Figure 3 Both the first limiting member 12 and the second limiting member 13 are provided with positioning holes 19, which are used to connect with the driving end of the driving assembly 3. Specifically, taking the driving assembly 3 as an example including a robotic arm, when it is necessary to drive the first limiting member 12 and the second limiting member 13 to slide via the robotic arm, the operating end of the robotic arm can be inserted into the corresponding positioning hole 19. Through the cooperation between the positioning hole 19 and the driving end, the driving assembly 3 and the first limiting member 12 and the second limiting member 13 can be quickly positioned and the driving force can be transmitted, thereby facilitating the sliding adjustment of the first limiting member 12 and the second limiting member 13. In addition, the positioning hole 19 can ensure that the point of application of the driving force remains consistent each time the adjustment is performed, thereby improving the repeatability and adjustment accuracy of the adjustment operation.

[0091] This application also provides a chip test fixture calibration method, implemented using the chip test fixture calibration system in any of the above embodiments; please refer to... Figure 1 , Figure 5 and Figure 6 and supplementary reference Figure 2 and Figure 3 The calibration method includes the following steps: Place the chip under test in the limiting area 15; Acquire a detection image of the chip under test placed in the limiting area 15, and obtain the chip width of the chip under test and the actual limiting width of the limiting area 15 based on the detection image; Calculate the width error between the chip width and the actual limit width; Determine whether the width error meets the preset tolerance conditions; If the width error meets the preset tolerance condition, the control drive component 3 will engage the locking member 14 in the first positioning groove 112 and the second positioning groove 16 that are aligned with each other, so as to restrict the sliding of the first limiting member 12 and the second limiting member 13 relative to the base 11. If the width error does not meet the preset tolerance condition, the control drive component 3 drives the first limit member 12 and the second limit member 13 to slide relative to each other to change the actual limit width, and returns to the step of acquiring the detection image of the chip under test placed in the limit area 15.

[0092] In this embodiment, the chip under test is first placed in the limiting area 15. This placement operation can be performed manually or by an automated feeding robot. After placement, the chip under test is located between the first limiting member 12 and the second limiting member 13.

[0093] Then, the visual recognition module 2 acquires a detection image of the chip under test placed in the limiting area 15, and performs data processing and analysis on the acquired detection image. The chip width is obtained by extracting the size information of the chip under test in the Y direction from the detection image, and the actual limiting width is obtained by extracting the size information of the limiting area 15 in the Y direction from the detection image.

[0094] Next, the visual recognition module 2 sends the obtained chip width and actual limit width to the control module 4. The control module 4 calculates the width error between the chip width and the actual limit width and compares the width error with the preset tolerance conditions stored in the control module 4 to determine whether the current actual limit width matches the chip width to an acceptable degree.

[0095] If the width error meets the preset tolerance condition, it means that the current limit width is adapted to the chip width. The control module 4 will send a locking command to the drive component 3 to trigger the drive component 3 to drive the locking device 14 to engage in the currently aligned first positioning groove 112 and second positioning groove 16, fixing the first limit member 12 and the second limit member 13 relative to the base 11, so that the limit width of the limit area 15 is locked, and the adjustment process ends.

[0096] If the width error does not meet the preset tolerance condition, the control module 4 will calculate the required sliding direction and displacement of the first limiting member 12 and the second limiting member 13 in the Y direction based on the width error, and convert the calculation result into a drive command and send it to the drive component 3. After receiving the drive command, the drive component 3 will drive the first limiting member 12 and the second limiting member 13 to slide relative to each other in the Y direction to change the actual limiting width. After the sliding operation is completed, the process will return to the step of acquiring the detection image of the chip under test placed in the limiting area 15 through the vision recognition module 2. That is, the chip width and the actual limiting width will be re-acquired through the vision recognition module 2, and the width error will be recalculated through the control module 4 to determine again whether the width error meets the preset tolerance condition. The above steps can be repeated until the width error meets the preset tolerance condition and then the locking operation is performed.

[0097] For other specific structures of the chip test fixture calibration system, please refer to the description of the above embodiments. Since the chip test fixture calibration method in this embodiment adopts all the technical solutions of all the above embodiments, it includes at least all the beneficial effects brought about by the technical solutions of the above embodiments. That is, based on visual guidance and closed-loop feedback control, the limiting width of the limiting area 15 can be adaptively adjusted for different specifications, including chips under test with different widths, and automatically locked after automatic adjustment. This realizes rapid changeover of the chip test fixture in multi-specification production scenarios without the need to equip a test fixture specifically for each specification of chip. This reduces the input of material costs, labor costs, and warehousing management pressure, and also eliminates the positioning deviation introduced by manual operation in the measurement, judgment, and adjustment stages. It improves the positioning accuracy and consistency of the adjustment results of the limiting width adjustment, thereby improving the testing efficiency and testing reliability while ensuring the reliability of chip testing.

[0098] In one implementation, please refer to Figure 1 , Figure 5 and Figure 6 and supplementary reference Figure 2 and Figure 3 After the step where the width error meets the preset tolerance condition, the following position calibration step is also included: The actual center position of the chip under test is obtained from the detected image; Calculate the positional error between the actual center position and the desired center position; If the position error exceeds the preset position tolerance, the position of the chip under test is adjusted by the external positioning mechanism, and the process returns to the step of acquiring the detection image of the chip under test placed in the limiting area 15. If the position error does not exceed the preset position tolerance, the control drive component 3 will perform the step of engaging the locking fastener 14 into the mutually aligned first positioning groove 112 and second positioning groove 16.

[0099] This embodiment further adds a position calibration step to further verify and adjust the placement position of the chip under test in the limiting area 15 after the width adjustment operation is completed and before the locking operation is performed.

[0100] Specifically, after the control module 4 determines that the width error meets the preset tolerance condition, the vision recognition module 2 obtains the actual center position of the chip under test in the limiting area 15 based on the acquired detection image. This actual center position can be obtained by extracting the edge contour of the chip under test in the detection image and calculating its geometric center. The control module 4 pre-stores the desired center position of the chip under test in the limiting area 15; this desired center position is the target placement position of the chip under test in the limiting area 15. The control module 4 compares the actual center position with the desired center position and calculates the positional error between them. This positional error can include positional deviation in the X direction and positional deviation in the Y direction.

[0101] The preset tolerance condition is limited by a preset tolerance threshold. The preset tolerance threshold is set to 0.03 mm. In other embodiments of this application, it can be other values, which are not limited here. The control module 4 calculates the width error between the chip width and the actual limiting width. When the absolute value of the width error is less than or equal to 0.03 mm, it is determined that the preset tolerance condition is met, and a locking operation is performed; otherwise, it is determined that the condition is not met, and the control drive component 3 drives the first limiting member 12 and the second limiting member 13 to slide relative to each other. The preset tolerance threshold is set based on the fact that there is a 0.10 mm gap between the limiting wall surface 151 and the corresponding side of the chip under test. The 0.03 mm tolerance threshold is about one-third of this gap. On the one hand, it can ensure that the limiting area 15 has sufficient limiting effect on the chip under test, and avoid the chip from shifting during the test due to excessive gap, which would affect the electrical contact reliability between the probe and the pad; on the other hand, it can leave a margin for the measurement error of the visual recognition module 2 and the repeatability error of the mechanical adjustment of the first limiting member 12 and the second limiting member 13, and avoid over-adjustment.

[0102] If the position error does not exceed the preset position tolerance, it means that the current placement position of the chip under test in the limiting area 15 has met the test requirements. The control module 4 will control the drive component 3 to drive the locking device 14 to perform a locking operation on the first limiting member 12 and the second limiting member 13.

[0103] If the position error exceeds the preset position tolerance, it indicates that the current position of the chip under test in the limiting area 15 has deviated from the target placement position. At this time, the control module 4 can send a position adjustment command to the external positioning mechanism. The external positioning mechanism can refer to the XY displacement stage connected to the test machine 5, or it can refer to the robotic arm used to hold the chip under test. The external positioning mechanism fine-tunes the position of the chip under test according to the position adjustment command. The adjustment direction is the X and Y directions, and the adjustment amount is the magnitude of the position error. After the external positioning mechanism completes the position adjustment, it will re-acquire the detection image of the chip under test placed in the limiting area 15 through the vision recognition module 2 to re-acquire the chip width, actual limiting width, and actual center position, and re-perform the width error judgment and position error judgment. If the recalculated width error still meets the preset tolerance condition and the position error does not exceed the preset position tolerance, the control module 4 will control the drive component 3 to perform a locking operation.

[0104] It should be noted that when the external positioning mechanism adjusts the position of the chip under test, the first limiting member 12 and the second limiting member 13 are still in a free sliding state without being locked. However, the first limiting member 12 and the second limiting member 13 have been adjusted to a position that matches the width of the chip through the previous width adjustment steps. Therefore, the chip under test is constrained by the first limiting member 12 and the second limiting member 13 in the Y direction. The adjustment amount of the external positioning mechanism in the Y direction can only be fine-tuned within the gap range allowed by the limiting width. The setting of this gap range is sufficient to compensate for the small position deviation generated by the chip under test during placement.

[0105] Through the above-described position calibration steps, this embodiment further achieves position calibration of the chip under test within the limiting area 15 based on automatic width matching, so that the center position of the chip under test can meet the test requirements, thereby ensuring that the probe can accurately align with the pads of the chip under test, avoiding misalignment or poor contact between the probe and the pads due to chip position offset, and further improving the reliability of the test.

[0106] In one implementation, please refer to Figure 1 , Figure 5 and Figure 6 and supplementary reference Figure 2 and Figure 3 The steps for obtaining the chip width of the chip under test and the actual limiting width of the limiting region 15 based on the detection image include: The detected image is preprocessed, including grayscale conversion and filtering. Edge detection is performed on the preprocessed image to extract the edge contour of the chip under test; Connectivity analysis is performed on the extracted edge contours to extract closed contours; Perform area filtering on closed contours to remove interfering contours with areas smaller than the minimum area threshold or larger than the maximum area threshold. The minimum bounding rectangle is calculated using the rotating caliper algorithm for the closed contour that has passed the area filtering operation, so as to obtain the center pixel coordinates, pixel width and pixel height of the minimum bounding rectangle; Using the camera calibration results, the center pixel coordinates and pixel width are converted into physical coordinates and physical width in the world coordinate system, thereby obtaining the chip width and actual limit width.

[0107] In this embodiment, after the visual recognition module 2 acquires the detection image, it first performs preprocessing operations on the detection image. The preprocessing operations include grayscale conversion and filtering; grayscale conversion is used to convert the acquired color detection image into a grayscale image to facilitate subsequent edge detection processing; the filtering can use Gaussian filtering to suppress noise and fine texture interference in the detection image, avoiding the adverse effects of noise on subsequent edge detection.

[0108] After preprocessing, the visual recognition module 2 performs edge detection on the preprocessed detection image to extract the edge contours of the chip under test. Edge detection can employ the Canny edge detection algorithm, which, through steps such as calculating image gradients, non-maximum suppression, and double threshold detection, can accurately extract edge information from the image.

[0109] After edge detection is completed, the visual recognition module 2 performs connected component analysis on the extracted edge contours to extract closed contours. Connected component analysis divides interconnected pixels in the image into independent regions, thereby separating each independent contour from the image.

[0110] After extracting the closed contours, the visual recognition module 2 performs area filtering on each closed contour. The area filtering operation is used to remove contours with an area smaller than the minimum area threshold and contours with an area larger than the maximum area threshold. Among them, contours with too small an area are usually noise points or tiny interference objects, while contours with too large an area may be background or other non-chip objects. The area filtering operation can exclude these interference contours, thereby retaining the valid contours that match the size of the chip under test.

[0111] For the closed contour retained after area filtering, the visual recognition module 2 uses a rotating caliper algorithm to calculate the minimum bounding rectangle of the closed contour, thereby obtaining the center pixel coordinates, pixel width, and pixel height of the minimum bounding rectangle. The rotating caliper algorithm can find the smallest bounding rectangle among all bounding rectangles of the closed contour. The longer side of this minimum bounding rectangle corresponds to the length direction of the chip under test, and the shorter side corresponds to the width direction of the chip under test. For a normally placed rectangular chip, the dimension of its minimum bounding rectangle in the Y direction corresponds to the chip width.

[0112] After obtaining the center pixel coordinates and pixel width, the visual recognition module 2 uses the camera calibration results to convert the center pixel coordinates into physical coordinates in the world coordinate system, and the pixel width into physical width in the world coordinate system, thereby obtaining the chip width of the chip under test and the actual limiting width of the limiting area 15. The camera calibration results include camera intrinsic parameters and pixel-to-millimeter conversion ratio. These calibration results are obtained in advance through the calibration board and stored in the control module 4 before the system is used for the first time.

[0113] Through the above image processing steps, the visual recognition module 2 can simultaneously extract the chip width of the chip under test and the actual limiting width of the limiting area 15 from a single detection image, providing an accurate data source for subsequent width error calculation.

[0114] In one implementation, please refer to Figure 1 , Figure 5 and Figure 6 and for reference Figure 2 and Figure 3 After calculating the minimum bounding rectangle of the closed contour obtained by area filtering using the rotating caliper algorithm, the process also includes: Calculate the rectangularity of the closed contour using the following formula: Ri =Ai / (wi hi) Where Ri is the rectangularity of the closed contour, Ai is the area of ​​the closed contour, wi is the pixel width of the minimum bounding rectangle, and hi is the pixel height of the minimum bounding rectangle. Only retain closed contours with a rectangle size greater than a preset rectangle size threshold.

[0115] This embodiment is used to further filter the closed contours retained based on image processing operations in the above embodiments. Specifically, after removing interfering contours with excessively small or large areas through area filtering, the visual recognition module 2 calculates the rectangularity of each retained closed contour. The formula for calculating the rectangularity is Ri=Ai / (wi) Let Ri be the rectangularity of the i-th closed contour, Ai be the area of ​​the closed contour, wi be the pixel width of the minimum bounding rectangle of the closed contour, and hi be the pixel height of the minimum bounding rectangle of the closed contour. For an ideal rectangle, its contour area is equal to the area of ​​the minimum bounding rectangle, so the rectangularity Ri is equal to 1; for a circle or irregular shape, its contour area is significantly smaller than the area of ​​the minimum bounding rectangle, so the rectangularity Ri is significantly less than 1.

[0116] After calculating the rectangularity of each closed contour, the visual recognition module 2 compares the rectangularity of each closed contour with a preset rectangularity threshold, retaining only closed contours with a rectangularity greater than the preset rectangularity threshold, and discarding closed contours with a rectangularity less than or equal to the preset rectangularity threshold; wherein, the preset rectangularity threshold can be set to a value close to 1.

[0117] By performing a rectangle verification in this embodiment, interference objects of circular, elliptical, or irregular shapes that may exist in the image can be eliminated, ensuring that the retained closed contour accurately corresponds to the rectangular shape of the chip under test, thereby improving the accuracy of chip width detection.

[0118] After the above two screening operations of area filtering and rectangle verification, the closed contour retained by the visual recognition module 2 is the effective contour that matches the shape and size of the chip under test. Subsequently, the rotating caliper algorithm is used to calculate the minimum bounding rectangle of the effective contour and convert the pixel width to the physical width to ensure the accuracy and reliability of the final detection result.

[0119] In one implementation, please refer to Figure 1 , Figure 5 and Figure 6 and supplementary reference Figure 2 and Figure 3 The preset rectangle size threshold is 0.84~0.86.

[0120] In this embodiment, the preset rectangularity threshold can be set to any value between 0.84 and 0.86, preferably 0.85. The lower limit of this range, 0.84, can effectively eliminate common non-rectangular interference objects in the image, while the upper limit, 0.86, can accommodate slight decreases in the rectangularity of the chip in the image due to optical distortion or edge blurring. By setting the preset rectangularity threshold within this range, the visual recognition module 2 can ensure screening accuracy while possessing sufficient fault tolerance, avoiding the erroneous removal of actually valid chip contours due to improper threshold setting or the retention of invalid contours due to an excessively low threshold.

[0121] In one implementation, please refer to Figure 1 , Figure 5 and Figure 6 and supplementary reference Figure 2 and Figure 3 Before the step of converting the center pixel coordinates and pixel width to physical coordinates and physical width in the world coordinate system using the camera calibration results, the following steps are also included: Obtain the rotation angle θi of the minimum bounding rectangle. The rotation angle θi is the angle between the long side of the minimum bounding rectangle and the u-axis of the image coordinate system. The rotation angle θi satisfies: -90°≤θi≤0°. Determine whether the rotation angle θi exceeds the preset angle tolerance range; If the rotation angle θi exceeds the preset angle tolerance range, a position adjustment command is output to rotate the chip under test so that the long side of the chip under test is parallel to the length direction of the limiting area 15.

[0122] This embodiment adds a step of detecting and correcting the placement angle of the chip under test before converting the center pixel coordinates and pixel width into physical coordinates and physical width.

[0123] Specifically, when calculating the minimum bounding rectangle, the visual recognition module 2 simultaneously obtains the rotation angle θi of the minimum bounding rectangle using a rotating caliper algorithm. This rotation angle θi is the angle between the longer side of the minimum bounding rectangle and the u-axis of the image coordinate system, with a value range of -90° ≤ θi ≤ 0°. Here, θi = 0° indicates that the longer side of the chip under test is parallel to the u-axis, and the closer θi is to -90°, the larger the deflection angle of the chip under test. The visual recognition module 2 sends this rotation angle θi to the control module 4, which determines whether the rotation angle θi exceeds a preset angle tolerance range. The preset angle tolerance range can be set according to the test accuracy requirements, for example, set to -2° ≤ θi ≤ 2°, which allows the chip under test to deflect within ±2° relative to the target direction.

[0124] If the rotation angle θi does not exceed the preset angle tolerance range, it indicates that the placement angle of the chip under test in the limiting area 15 meets the test requirements. The control module 4 does not perform angle adjustment and directly proceeds to the subsequent size conversion step. If the rotation angle θi exceeds the preset angle tolerance range, it indicates that the placement angle of the chip under test in the limiting area 15 deviates from the target direction. At this time, the control module 4 outputs a position adjustment command to the external positioning mechanism. This command contains the direction and angle value that the chip under test needs to rotate. The external positioning mechanism drives the chip under test to rotate around its center by the corresponding angle according to the command to correct the deflection of the chip under test, so that the long side of the chip under test is parallel to the length direction of the limiting area 15. The length direction of the chip under test in the limiting area 15 is the X direction. When the long side of the chip under test is parallel to the X direction, the rotation angle θi of the minimum bounding rectangle extracted by the vision recognition module 2 is 0°.

[0125] After the rotation correction of the chip under test is completed, the visual recognition module 2 re-acquires the detection image and recalculates the minimum bounding rectangle and its rotation angle. The control module 4 then determines whether the rotation angle exceeds the preset angle tolerance range. The above process can be repeated until the rotation angle of the chip under test meets the preset angle tolerance range, and then the conversion from pixel coordinates and pixel width to physical coordinates and physical width is performed.

[0126] Through the above angle detection and correction steps, this embodiment further realizes automatic correction of the placement angle of the chip under test based on width matching and position calibration, ensuring that the long side direction of the chip under test is consistent with the length direction of the limiting area 15 before locking, thereby ensuring that the probe array and the pad arrangement direction of the chip under test are aligned, avoiding misalignment of probes and pads due to angle deflection, and further improving the reliability of the test.

[0127] In one implementation, please refer to Figure 1 , Figure 5 and Figure 6 and for reference Figure 2 and Figure 3 If the width error does not meet the preset tolerance condition, the control drive component 3 drives the first limit member 12 and the second limit member 13 to slide relative to each other to change the actual limit width, and returns to the step of acquiring the detection image of the chip under test placed in the limit area 15. The sliding adjustment amount δWn used during the nth return execution is: δWn=Kp γ^(n-1) ΔWn Where Kp is the initial gain coefficient, γ is the gain attenuation coefficient, 0 < γ < 1, ΔWn is the width error before the nth return execution, and n is the cumulative number of return executions.

[0128] In actual operation, when the width error does not meet the preset tolerance condition and the first limiting member 12 and the second limiting member 13 need to slide relative to each other, the control module 4 needs to calculate the adjustment amount for each slide. During multiple iterative adjustments, if the same gain coefficient is used each time, overshoot or oscillation may occur when approaching the target value, causing the adjustment process to fail to converge stably. To solve this problem, this embodiment adopts a gain attenuation control strategy.

[0129] Specifically, assuming the current step is the nth return to execute the image acquisition and detection step, i.e., the nth iteration adjustment, the sliding adjustment amount δWn is calculated according to the following formula: δWn=Kp γ^(n-1) ΔWn. Where Kp is the initial gain coefficient, which determines the response amplitude during the initial adjustment; γ is the gain attenuation coefficient, 0 < γ < 1, which makes the gain coefficient γ^(n-1) gradually decrease as the number of iterations n increases; ΔWn is the width error before the nth return execution; n is the cumulative number of return executions, that is, the number of times it is accumulated from the first time.

[0130] The calculation formula means that during the initial adjustment, the gain coefficient is Kp, and the control module 4 drives the first limit member 12 and the second limit member 13 to slide with a large adjustment step size to quickly reduce the width error. As the number of iterations increases, the gain coefficient gradually decreases according to powers of γ, and the adjustment step size decreases successively. When the width error gradually approaches zero, the smaller adjustment step size can avoid overshoot or oscillation caused by over-adjustment, so that the limit width can be stably converged to near the target value, thereby improving the stability and convergence efficiency of the adjustment process. The specific value of γ can be set according to the response characteristics of the actual system. For example, setting it to 0.8 will make the gain coefficient of each iteration decrease by 20% compared to the previous one, achieving a balance between rapid approximation and stable convergence.

[0131] In one implementation, please refer to Figure 1 , Figure 5 and Figure 6 and supplementary reference Figure 2 and Figure 3 Before each return to the step of acquiring the detection image of the chip under test placed in the limiting area 15, the following anti-vibration steps are also included: Get the width error ΔWn before the current return execution, and the width errors ΔWn-1 and ΔWn-2 before the previous two return executions; A series of sign inversions is determined to have occurred if at least one of the following two conditions is met: ΔWn-2>0, and ΔWn-1<0, and ΔWn>0; ΔWn-2<0, and ΔWn-1>0, and ΔWn<0; Multiply the sliding adjustment amount δWn used in the nth return execution by the damping factor ζ to obtain the actual sliding adjustment amount for this return execution, where 0 < ζ < 1.

[0132] In practical operation, during the iterative adjustment of the attenuation gain using the above embodiments, although the overshoot can be suppressed to some extent by successively decreasing the gain coefficient, in certain situations, such as when the initial width error is large or when the system has nonlinear friction, the adjustment amount may still alternate between the two sides of the target value, that is, the sign of the width error repeatedly reverses in consecutive iterations. This continuous sign reversal indicates that the adjustment process has an oscillating trend, and if no intervention is taken, it may lead to a prolonged adjustment time or even failure to converge effectively.

[0133] To address the aforementioned issues, this embodiment adds an anti-oscillation judgment step before each return to execute the image acquisition and detection step. Specifically, the control module 4 acquires the width error ΔWn before the current return execution, as well as the width errors ΔWn-1 and ΔWn-2 before the previous two return executions. The control module 4 determines whether at least one of the following two conditions is met: Condition 1 is ΔWn-2>0, ΔWn-1<0, and ΔWn>0; Condition 2 is ΔWn-2<0, ΔWn-1>0, and ΔWn<0. These two conditions correspond to the sign change pattern of the width error in three consecutive iterations, i.e., positive-negative-positive or negative-positive-negative. If either condition is met, it is determined that the current adjustment process has experienced continuous sign reversal, i.e., there is an oscillation trend.

[0134] When a continuous sign reversal is detected, control module 4 multiplies the sliding adjustment amount δWn used during this return execution by the damping factor ζ, and then uses the actual sliding adjustment amount ζ. δWn represents the actual sliding adjustment amount for this return execution, where 0 < ζ < 1. The specific value of the damping factor ζ can be set according to the system characteristics, for example, set to 0.5. By introducing the damping factor ζ, the control module 4 actively reduces the adjustment step size when it detects an oscillation trend, in order to suppress over-adjustment and allow the width error to smoothly approach zero.

[0135] The above-mentioned anti-oscillation steps effectively suppress the oscillation trend during the adjustment process by applying additional damping to the adjustment amount when the width error is detected to be continuously reversed, thus avoiding repeated overshoot caused by excessive adjustment, thereby further improving the stability and convergence speed of the adjustment process.

[0136] The above description is merely an exemplary embodiment of this application and does not limit the patent scope of this application. Any equivalent structural transformations made based on the technical concept of this application and the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this application.

Claims

1. A chip test fixture calibration system, characterized in that, include: The test fixture assembly (1) includes a base (11), a first limiting member (12), a second limiting member (13), and a locking member (14); the base (11) is provided with a limiting groove (111) and a plurality of first positioning grooves (112), the plurality of first positioning grooves (112) being arranged on the edge of the limiting groove (111); the first limiting member (12) and the second limiting member (13) are slidably engaged in the limiting groove (111), and the first limiting member (12) and the second limiting member (13) enclose a limiting area. Domain (15); the first limiting member (12) and the second limiting member (13) move closer to each other or further away from each other during the sliding process to adjust the limiting width of the limiting area (15); the first limiting member (12) and the second limiting member (13) are each provided with a plurality of second positioning grooves (16), the second positioning grooves (16) and the first positioning grooves (112) are arranged opposite to each other in the mating direction, and the mating direction intersects or is perpendicular to the sliding direction of the first limiting member (12) and the sliding direction of the second limiting member (13); The visual recognition module (2) is used to acquire an image of the chip under test placed in the limiting area (15) to obtain the chip width of the chip under test and the actual limiting width of the limiting area (15); The drive component (3) is connected to the first limiting member (12), the second limiting member (13) and the locking member (14); The control module (4) is electrically connected to the visual recognition module (2) and the driving component (3); the control module (4) is used to control the driving component (3) to drive the first limiting member (12) and the second limiting member (13) to slide relative to each other until the chip width and the actual limiting width meet the preset tolerance condition; and the control module (4) is used to control the driving component (3) to engage the locking fastener (14) in the first positioning groove (112) and the second positioning groove (16) that are aligned with each other, so as to restrict the sliding of the first limiting member (12) and the second limiting member (13) relative to the base (11).

2. The chip testing fixture calibration system as described in claim 1, characterized in that, The limiting groove (111) includes a first sidewall (1111) and a second sidewall (1112) disposed opposite to each other; The first limiting member (12) includes a first main body (121) and a plurality of first partition strips (122). The first main body (121) is slidably fitted in the limiting groove (111) along the first sidewall (1111). The plurality of first partition strips (122) are spaced apart on the first main body (121) along the sliding direction of the first main body (121), and the first partition strips (122) extend in a direction close to the second sidewall (1112). The second limiting member (13) includes a second main body (131) and Multiple second partition strips (132) are provided, and the second main body (131) slides along the second sidewall (1112) in the limiting groove (111). The multiple second partition strips (132) are arranged at intervals on the second main body (131) along the sliding direction of the second main body (131), and the second partition strips (132) extend in a direction close to the first sidewall (1111). Each pair of adjacent first partition strips (122) and second partition strips (132) forms a limiting area (15).

3. The chip testing fixture calibration system as described in claim 2, characterized in that, The limiting groove (111) is formed on the top surface of the base (11); the locking fastener (14) includes a locking block (141) and a threaded connector (142), the threaded connector (142) being used to lock the locking block (141) onto the base (11); The first positioning groove (112) includes a plurality of first grooves (1121), which are formed on the top of the first sidewall (1111) and spaced apart along the first sidewall (1111); the second positioning groove (16) includes a plurality of second grooves (161), which are formed on the top of the first main body (121) and facing the first sidewall (1111), and spaced apart along the sliding direction of the first main body (121); the locking block (141) is used to insert into the aligned first grooves (1121) and second grooves (161) along the insertion direction, which is perpendicular to the sliding direction; And / or, the first positioning groove (112) includes a plurality of third grooves (1122), the plurality of third grooves (1122) being opened at the top of the second sidewall (1112) and spaced apart along the second sidewall (1112); the second positioning groove (16) includes a plurality of fourth grooves (162), the fourth grooves (162) being opened at the top of the second main body (131) and facing the second sidewall (1112), the plurality of fourth grooves (162) being spaced apart along the sliding direction of the second main body (131); the locking block (141) is used to insert into the mutually aligned third grooves (1122) and fourth grooves (162) along the insertion direction, the insertion direction being perpendicular to the sliding direction.

4. The chip test fixture calibration system as described in claim 3, characterized in that, When the locking block (141) is inserted into the first groove (1121) and the second groove (161) that are aligned with each other, the top surface of the locking block (141) is higher than the top surface of the base (11) and the top surface of the first main body (121); And / or, when the locking block (141) is inserted into the mutually aligned third groove (1122) and fourth groove (162), the top surface of the locking block (141) is higher than the top surface of the base (11) and the top surface of the second main body (131); And / or, the cross-sectional area of ​​the locking block (141) gradually decreases from top to bottom; And / or, the cross-sectional area of ​​the first tank (1121) and the cross-sectional area of ​​the second tank (161) both gradually decrease from top to bottom; And / or, the cross-sectional area of ​​the third groove (1122) and the cross-sectional area of ​​the fourth groove (162) both gradually decrease from top to bottom.

5. The chip test fixture calibration system as described in any one of claims 1 to 4, characterized in that, The multiple sidewalls that enclose the limiting area (15) have limiting wall surfaces (151) and guide wall surfaces (152). The limiting wall surface (151) is located between the bottom wall of the limiting groove (111) and the guide wall surface (152). The limiting wall surface (151) is perpendicular to the bottom wall of the limiting groove (111). The guide wall surface (152) gradually slopes outward along a direction perpendicular to the bottom wall of the limiting groove (111). And / or, the first limiting member (12) is provided with at least two first waist-shaped holes (123) at intervals, the first waist-shaped holes (123) extending in a direction parallel to the limiting width; the bottom wall of the limiting groove (111) is provided with at least two first guide posts (17) at intervals, the first guide posts (17) being correspondingly inserted and fitted into the first waist-shaped holes (123) to restrict the first limiting member (12) from sliding in a direction parallel to the limiting width; And / or, the second limiting member (13) is provided with at least two second waist-shaped holes (133) at intervals, the second waist-shaped holes (133) extending in a direction parallel to the limiting width; the bottom wall of the limiting groove (111) is provided with at least two second guide posts (18) at intervals, the second guide posts (18) correspondingly passing through and engaging in the second waist-shaped holes (133) to restrict the second limiting member (13) from sliding in a direction parallel to the limiting width; And / or, each of the first positioning slots (112) is provided with a corresponding chip size mark (113); And / or, the first limiting member (12) and the second limiting member (13) are both provided with positioning holes (19), which are used to dock with the driving end of the driving component (3).

6. A chip test fixture calibration method, characterized in that, The calibration method is implemented using the chip test fixture calibration system as described in any one of claims 1 to 5; the calibration method includes the following steps: Place the chip under test in the limiting area (15); Acquire a detection image of the chip under test placed in the limiting area (15), and obtain the chip width of the chip under test and the actual limiting width of the limiting area (15) based on the detection image; Calculate the width error between the chip width and the actual limiting width; Determine whether the width error meets the preset tolerance condition; If the width error meets the preset tolerance condition, the drive component (3) is controlled to engage the locking fastener (14) in the first positioning groove (112) and the second positioning groove (16) that are aligned with each other, so as to restrict the sliding of the first limiting member (12) and the second limiting member (13) relative to the base (11); If the width error does not meet the preset tolerance condition, the driving component (3) is controlled to drive the first limiting member (12) and the second limiting member (13) to slide relative to each other to change the actual limiting width, and then the step of collecting the detection image of the chip under test placed in the limiting area (15) is returned.

7. The calibration method according to claim 6, characterized in that, After the step where the width error meets the preset tolerance condition, the following position calibration step is also included: The actual center position of the chip under test is obtained from the detected image. Calculate the positional error between the actual center position and the desired center position; If the position error exceeds the preset position tolerance, the position of the chip under test is adjusted by an external positioning mechanism, and the step of collecting the detection image of the chip under test placed in the limiting area (15) is returned. If the position error does not exceed the preset position tolerance, then the step of controlling the drive component (3) to engage the locking fastener (14) in the first positioning groove (112) and the second positioning groove (16) that are aligned with each other is executed.

8. The calibration method according to claim 6, characterized in that, The step of obtaining the chip width of the chip under test and the actual limiting width of the limiting region (15) based on the detection image includes: The detected image is preprocessed, including grayscale conversion and filtering. Edge detection is performed on the detection image after the preprocessing operation to extract the edge contour of the chip under test; Connectivity analysis is performed on the extracted edge contours to extract closed contours; An area filtering operation is performed on the closed contour to remove interfering contours with an area smaller than the minimum area threshold or an area larger than the maximum area threshold. The minimum bounding rectangle is calculated using the rotating caliper algorithm on the closed contour obtained by the area filtering operation, so as to obtain the center pixel coordinates, pixel width and pixel height of the minimum bounding rectangle; Using the camera calibration results, the center pixel coordinates and the pixel width are converted into physical coordinates and physical width in the world coordinate system, thereby obtaining the chip width and the actual limiting width.

9. The calibration method according to claim 8, characterized in that, After the step of calculating the minimum bounding rectangle of the closed contour obtained by the area filtering operation using the rotating caliper algorithm, the method further includes: The rectangularity of the closed contour is calculated using the following formula: Ri=Ai / (wi hi) Where Ri is the rectangularity of the closed contour, Ai is the area of ​​the closed contour, wi is the pixel width of the minimum bounding rectangle, and hi is the pixel height of the minimum bounding rectangle; Only the closed contours whose rectangles are greater than a preset rectangle threshold are retained.

10. The calibration method according to claim 9, characterized in that, The preset rectangularity threshold is 0.84~0.

86.

11. The calibration method according to claim 8, characterized in that, Before the step of converting the center pixel coordinates and the pixel width into physical coordinates and physical width in the world coordinate system using the camera calibration results, the method further includes: Obtain the rotation angle θi of the minimum bounding rectangle, where the rotation angle θi is the angle between the long side of the minimum bounding rectangle and the u-axis of the image coordinate system, and the rotation angle θi satisfies: -90°≤θi≤0°; Determine whether the rotation angle θi exceeds the preset angle tolerance range; If the rotation angle θi exceeds the preset angle tolerance range, a position adjustment command is output to rotate the chip under test so that the long side of the chip under test is parallel to the length direction of the limiting area (15).

12. The calibration method according to claim 6, characterized in that, If the width error does not meet the preset tolerance condition, the driving component (3) is controlled to drive the first limiting member (12) and the second limiting member (13) to slide relative to each other to change the actual limiting width, and the process returns to the step of acquiring the detection image of the chip under test placed in the limiting area (15). The sliding adjustment amount δWn used during the nth return execution is: δWn=Kp γ^(n-1) ΔWn Where Kp is the initial gain coefficient, γ is the gain attenuation coefficient, 0 < γ < 1, ΔWn is the width error before the nth return execution, and n is the cumulative number of return executions.

13. The calibration method according to claim 12, characterized in that, Before each return to the step of acquiring the detection image of the chip under test placed in the limiting area (15), the following anti-vibration step is also included: Obtain the width error ΔWn before the current return execution, and the width errors ΔWn-1 and ΔWn-2 before the previous two return executions; A series of sign inversions is determined to have occurred if at least one of the following two conditions is met: ΔWn-2>0, and ΔWn-1<0, and ΔWn>0; ΔWn-2<0, and ΔWn-1>0, and ΔWn<0; Multiply the sliding adjustment amount δWn used in the nth return execution by the damping factor ζ to obtain the actual sliding adjustment amount for this return execution, where 0 < ζ < 1.

Images