High-efficiency screw automatic locking device and control method

Abstract

The application discloses a kind of high-efficiency screw automatic locking device and control method, comprising: machine body, with conveying mechanism of conveying workpiece to be processed;Fixed mechanism, including servo motor driven turnover table, locking fixture and pedestal, for clamping workpiece and realizing turnover;Locking mechanism, including first locking assembly and second locking assembly, respectively configured to perform locking operation of different specifications screw;Visual positioning system, integrated in locking fixture upper, for obtaining the hole characteristics of screw hole on workpiece and tracking the turnover posture of locking fixture;And control system.Through the cooperation of fixed mechanism and locking mechanism, first locking assembly and second locking assembly respectively work in two stations vertically downward and side or upside, respectively lock two different specifications screws on static contact and terminal strip on plastic shell circuit breaker.Relative to prior art, reduce the replacement of screw bit and the change of torque in locking process, increase the precision and efficiency of automatic locking.

Description

Technical Field

[0001] This invention relates to the field of automation technology, and in particular to a high-efficiency automatic screw fastening device and control method. Background Technology

[0002] In the field of industrial power transmission and distribution, the conductive system of a residual current circuit breaker (RCCB) is a core electrical connection component, and its assembly quality directly affects the safety and reliability of the equipment. This conductive system mainly consists of the inlet terminal, the outlet terminal, and the conductive plate. The stationary contact and the terminal block need to be secured using two different sizes of standard screws.

[0003] During the fastening process, the stationary contact and the terminal block each require fastening with two different sizes of standard screws, each with a different torque value, necessitating the use of different screwdriver bits. Existing automatic fastening devices first fasten one type of screw, then require changing the screwdriver bit and adjusting the output torque, resulting in insufficient efficiency and accuracy.

[0004] Therefore, it is necessary to provide an efficient automatic screw fastening device and control method to solve the above-mentioned technical problems. Summary of the Invention

[0005] This invention overcomes the shortcomings of the prior art and provides a highly efficient automatic screw fastening device and control method.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is: a high-efficiency automatic screw fastening device, comprising:

[0007] The machine body is equipped with a conveying mechanism for transporting the workpieces to be processed;

[0008] The fixing mechanism includes a servo motor-driven tilting table, a locking fixture, and a base, used to clamp the workpiece and achieve tilting;

[0009] The locking mechanism includes a first locking component and a second locking component, which are respectively configured to perform locking operations on screws of different specifications;

[0010] A vision positioning system, integrated above the locking fixture, is used to acquire the hole features of the screw holes on the workpiece and track the flipping posture of the locking fixture.

[0011] and control systems, including:

[0012] Main control module;

[0013] The fastening path planning module divides the screw holes on the workpiece into first screw holes and second screw holes corresponding to the first and second fastening components, based on the hole characteristics of the screw holes, and plans the first fastening path and the second fastening path respectively.

[0014] The positioning compensation calculation module calculates the positioning compensation after the flipping based on the flipping posture of the locking fixture;

[0015] The correction module corrects the second locking path based on positioning compensation.

[0016] In a preferred embodiment of the present invention, the locking fixture includes: an upper fixture, a lower fixture, and a servo electric cylinder for controlling the downward pressing of the upper fixture;

[0017] The upper surface of the upper fixture is provided with a contour positioning groove that matches the workpiece locking position;

[0018] Several elastic telescopic rods are provided on the opposing surfaces of the upper and lower fixtures;

[0019] The lower fixture and the servo electric cylinder are disposed on the upper surface of the tilting table. The upper end of the servo electric cylinder is connected to the upper fixture, which is located directly above the lower fixture.

[0020] In a preferred embodiment of the present invention, the first locking component is disposed directly above the locking fixture, and the angle between the second locking component and the first locking component is consistent with the flipping angle of the flipping table.

[0021] In a preferred embodiment of the present invention, the visual positioning system includes: a 3D vision module and a multispectral light source;

[0022] The 3D vision module is configured as a set of industrial cameras, which are vertically mounted above the locking fixture.

[0023] The multispectral light source is configured with infrared 850nm and blue light 450nm bands, and illuminates the workpiece surface at a 30° angle.

[0024] In a preferred embodiment of the present invention, the visual positioning system acquires the screw hole features on the workpiece, specifically as follows:

[0025] The workpiece fixed to the locking fixture is scanned from multiple angles to obtain surface point cloud data. The two types of screw holes on the workpiece are divided into first screw holes and second screw holes, and the center coordinates, depth and tilt angle of the holes are extracted respectively.

[0026] For the second screw hole, based on the preset flipping trajectory of the locking fixture, the center coordinates, depth and tilt angle parameters of the identified second screw hole are converted into the center coordinates, depth and tilt angle parameters of the flipped second screw hole.

[0027] In a preferred embodiment of the present invention, the visual positioning system tracks the flipping posture of the locking fixture, specifically as follows:

[0028] Real-time acquisition of point cloud data of the locking fixture surface;

[0029] The ICP algorithm is used to calculate the flipping posture [R, t] of the locking fixture. Specifically, the current frame point cloud is aligned with the initial frame point cloud, and the rotation matrix R and translation vector t are calculated using the following formula: Among them, P i For the current frame point cloud, Q i This is the point cloud for the initial frame.

[0030] In a preferred embodiment of the present invention, the calculation of positioning compensation is specifically as follows:

[0031] Extract Euler angles (α,β,γ) from the rotation matrix R, where β is the angle about the flip axis;

[0032] Read translation vector

[0033] In a preferred embodiment of the present invention, the correction of the second locking path specifically involves: correcting the second locking path point P based on the extracted angle β and translation vector t around the flip axis. 修正 =R(β)·P 初始 +t.

[0034] A control method for a high-efficiency automatic screw fastening device includes the following steps:

[0035] S1. Grab the workpiece from the conveyor mechanism and place it on the locking fixture to fix the workpiece;

[0036] S2. Using a visual positioning system, identify the features and positions of screw holes on the workpiece and classify them into first screw holes and second screw holes according to specifications.

[0037] S3. Based on the characteristics and positions of the first and second screw holes, plan the locking paths of the first and second locking components respectively, and control the first locking component to perform locking of the first screw based on the first locking path;

[0038] S4. Flip the locking fixture, and calculate the positioning compensation after flipping based on the flipping posture of the locking fixture tracked by the vision positioning system, and correct the second locking path.

[0039] S5. Control the second locking component to execute the modified second locking path to complete the locking of the second screw.

[0040] In a preferred embodiment of the present invention, the flipping angle of the locking fixture is 90° or 180°.

[0041] This invention addresses the shortcomings of the prior art and has the following beneficial effects:

[0042] (1) This invention provides a high-efficiency automatic screw fastening device. Through the coordinated arrangement of a fixing mechanism and a fastening mechanism, the first fastening component and the second fastening component work together in two positions, one vertically downward and the other sideways or upward, to fasten two different specifications of screws to the stationary contacts and terminal blocks of a molded case circuit breaker. Compared with the prior art, this reduces the need to change screwdriver bits and the torque changes during the fastening process. Furthermore, the setting of two different angle positions avoids motion interference between the two robotic arms and large displacements of the robotic arms, thereby increasing the accuracy and efficiency of automatic fastening.

[0043] (2) This invention utilizes the collaboration of a visual positioning system and a control system to perform a single visual positioning of the locking fixture and the workpiece, providing locking paths for the first and second locking components at different workstation angles. The visual positioning system tracks the flipping posture of the locking fixture, calculates positioning compensation in real time, corrects the locking path of the second locking component, and improves locking accuracy. This solves the problem of deviation in the second locking path caused by physical disturbances resulting from the flipping of the locking fixture, and avoids the limitation of relying on the same initial positioning for both locking operations. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 This is a front view of the fixing mechanism according to a preferred embodiment of the present invention;

[0046] Figure 2 This is a top view of the upper fixture according to a preferred embodiment of the present invention;

[0047] Figure 3 This is a control method diagram of a preferred embodiment of the high-efficiency automatic screw fastening device of the present invention;

[0048] In the diagram: 100, servo motor; 200, tilting table; 300, locking fixture; 400, base; 500, upper fixture; 600, lower fixture; 700, servo electric cylinder; 800, contour positioning groove; 900, elastic telescopic rod. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein. Therefore, the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0051] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the scope of protection of this application. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0052] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art will understand the specific meaning of the above terms in this application based on the specific circumstances.

[0053] The present invention provides an efficient automatic screw fastening device, comprising: a body, a fixing mechanism, a fastening mechanism, a vision positioning system and a control system (not shown in the figure) disposed on the body.

[0054] The machine body is equipped with a conveying mechanism for transporting the workpiece to be processed; the machine body has a mounting surface, and the conveying mechanism is mounted on the mounting surface. The conveying mechanism includes a conveyor belt, transfer rollers, or other structures capable of transporting the workpiece to be processed. Understandably, the workpiece is transported to the gripping area via the conveying mechanism, and a gripping device is used to move the workpiece to a designated position on a fixed mechanism. The gripping device can be a mechanical gripper, vacuum suction cup, or other device capable of gripping the workpiece; no limitation is made here.

[0055] It is worth noting that the workpiece is a molded case circuit breaker, and its stationary contacts and terminal block are fastened with screws of different specifications (e.g., M3 and M8). Furthermore, the two types of screws are adapted to different torques, i.e., the corresponding electric screwdriver parameters: torque: 8 N·m (M3) and 20 N·m (M8), speed: 800 rpm (M3) and 300 rpm (M8).

[0056] like Figure 1 As shown, the fixing mechanism includes a tilting table 200 driven by a servo motor 100, a locking fixture 300, and a base 400, used to clamp the workpiece and achieve tilting. The servo motor 100 is mounted on the base 400. The tilting table 200 is directly connected to the output end of the servo motor 100 through a harmonic reducer. An encoder is integrated at the end of the tilting shaft, with a repeatability accuracy of ≤0.01°. The tilting angle of the tilting table 200 is 90° or 180°. The locking fixture 300 is mounted on the tilting table 200. By adjusting the angle of the tilting table 200, the screw fastening surface of the workpiece faces different directions, enabling multi-station fastening of different screws on the same workpiece.

[0057] The first locking assembly is located directly above the locking fixture 300, and the angle between the second locking assembly and the first locking assembly is the same as the flipping angle of the flipping table 200.

[0058] like Figure 2 As shown, the locking fixture 300 includes: an upper fixture 500, a lower fixture 600, and a servo electric cylinder 700 for controlling the downward pressing of the upper fixture 500; the upper surface of the upper fixture 500 is provided with a contour positioning groove 800 that matches the locking position of the workpiece, and the shape of the lower surface of the upper fixture 500 matches the contour of the upper surface of the workpiece. The presence of the contour positioning groove 800 allows the locking position on the workpiece, i.e., the screw hole, to be exposed outside the locking fixture 300, ensuring accurate alignment of the locking position and facilitating automatic screw fastening in the later stage.

[0059] Several elastic telescopic rods 900 are provided on the opposing surfaces of the upper fixture 500 and the lower fixture 600. The diameter of the elastic telescopic rod 900 is preferably 8mm, the telescopic stroke is 10mm, and the preload spring force is 50N. The elastic telescopic rods 900 apply pressure evenly to the workpiece to avoid local stress concentration that could cause workpiece deformation.

[0060] The lower fixture 600 and the servo cylinder 700 are fixed to the upper surface of the tilting table 200. The upper end of the servo cylinder 700 is fixedly connected to one side of the upper fixture 500. The upper fixture 500 is located directly above the lower fixture 600. The servo cylinder 700 is vertically upward, with the upper end of the cylinder body slightly higher than the upper surface of the lower fixture 600. When the servo cylinder 700 is extended, the upper fixture 500 moves away from the lower fixture 600. When the servo cylinder 700 is retracted, the upper fixture 500 and the lower fixture 600 are locked together to fix the workpiece.

[0061] The locking mechanism includes a first locking component and a second locking component, which are respectively configured to perform locking operations on screws of different specifications. The first locking component and the second locking component have the same structure, both including: a six-axis vertical multi-joint robotic arm, and an electric screwdriver mounted on the end of the robotic arm. The electric screwdriver is connected to the robotic arm through a quick-change interface, and the end of the screwdriver integrates a force sensor to monitor the locking pressure and torque in real time.

[0062] Specifically, it also includes the main frame, which is a rectangular box frame that integrates an electric screwdriver drive unit and sensors. The top of the main frame is equipped with a standardized flange interface (ISO 9409-1-50-4-M6) to connect to the quick-change device at the end of the robotic arm. The bottom of the main frame is reserved with an electric screwdriver mounting slot and a screw feeding channel.

[0063] The first locking assembly uses a straight-shank miniature electric screwdriver, such as the DEPRAG DGD-5N, with a torque of 2-8 N·m and a speed of 0-1500 rpm; the second locking assembly uses a straight-shank heavy-duty electric screwdriver, such as the Atlas Copco QSB6, with a torque of 5-20 N·m and a speed of 0-800 rpm. The screwdrivers are fixed by a stainless steel floating bracket with built-in rubber damping pads (Shore A 70 hardness) to reduce vibration transmission. The screwdriver axis is aligned with the flange axis at the end of the robotic arm to ensure precise locking direction.

[0064] The screw feeding channels are specifically designed as follows: the first locking assembly is a flexible vibratory feeder adapted to M3-M5 screws, with a screw feeding tube inner diameter of 3.5mm; while the second locking assembly is a direct vibratory feeder adapted to M6-M8 screws, with a screw feeding tube inner diameter of 7mm. Furthermore, the screw feeding tube is connected to the electric screwdriver via a magnetic quick-change connector, with a changeover time of ≤30 seconds.

[0065] It is worth noting that the first locking component locks the front screw vertically downwards, the robot arm posture is fixed, and the path spacing is compact; the second locking component dynamically adjusts the locking angle according to the workpiece posture after flipping, including lateral or upward locking.

[0066] In this invention, the fixing mechanism and the locking mechanism are designed to work together. The first locking component and the second locking component work in two positions, one vertically downward and the other side or upward, respectively, to lock two different sizes of screws onto the stationary contacts and the terminal block of the molded case circuit breaker. Compared with the prior art, this reduces the need to change screwdriver bits and the torque changes during the locking process. Furthermore, the setting of two different angle positions avoids the movement interference of the two robotic arms and the large displacement of the robotic arms, thereby increasing the accuracy and efficiency of automatic locking.

[0067] The visual positioning system in this embodiment is integrated above the locking fixture 300 and is used to acquire the three-dimensional coordinates of the screw holes on the workpiece and track the flipping posture of the locking fixture 300 in real time. The visual positioning system includes a 3D vision module and a multispectral light source. The 3D vision module is configured as a set of industrial cameras and is vertically mounted above the locking fixture 300. The multispectral light source is configured with infrared 850nm and blue light 450nm bands and illuminates the workpiece surface at a 30° angle.

[0068] The features of screw holes on the workpiece are obtained through a vision positioning system, specifically:

[0069] 1) The workpiece fixed to the locking fixture 300 is scanned from multiple angles using a 3D vision system to obtain surface point cloud data. Two types of screw holes on the workpiece are divided into first screw holes and second screw holes, and the hole center coordinates, hole depth, and tilt angle are extracted for each. Hole center coordinates: The Hough circle detection algorithm is used to identify the screw hole contour, and sub-pixel edge fitting technology is used to calibrate the hole center coordinates. Hole depth and tilt angle: Phase-coded fringes are generated based on structured light projection, and the three-dimensional morphology of the hole is reconstructed through phase calculation. The hole axis direction vector (unit vector) is extracted. ) and hole depth.

[0070] 2) For the second screw hole, based on the preset locking fixture 300 flipping trajectory, the identified hole center coordinates, hole depth and tilt angle parameters of the second screw hole are converted into the hole center coordinates, hole depth and tilt angle parameters of the flipped second screw hole.

[0071] The rotation posture of the locking fixture 300 is tracked by a visual positioning system, specifically as follows:

[0072] 1) Use a 3D vision system to collect point cloud data of the 300 surface of the locking fixture in real time.

[0073] 2) The ICP (Iterative Closest Point) algorithm is used to calculate the flipping posture [R, t] of the locking fixture 300. Specifically, the current frame point cloud is aligned with the initial frame point cloud, and the rotation matrix R and translation vector t are calculated using the following formula: Among them, P i For the current frame point cloud, Qi This is the point cloud for the initial frame.

[0074] The control system includes: a main control module, a locking path planning module, a positioning compensation calculation module, and a correction module.

[0075] The main control module synchronously coordinates the conveying, locking, flipping, and attaching actions via the EtherCAT bus.

[0076] The fastening path planning module, based on the characteristics of the screw holes on the workpiece, divides them into first screw holes and second screw holes corresponding to the first and second fastening components, and plans the first fastening path and the second fastening path respectively; the planning of the first and second fastening paths includes the following steps:

[0077] 1) Set the center coordinates (x, y, z) and direction vector of the screw hole. Transform to the robot arm's base coordinate system; the transformation matrix is ​​P. base =T cam→base ·P cam , among which, T cam→base Obtained through hand-eye calibration.

[0078] Based on the robotic arm model, solve for the joint angle combination θ = [θ1, θ2, ..., θ3] that aligns the electric screwdriver tip with the hole axis. n ],satisfy

[0079] 2) The RRT* (Rapid Extended Random Tree) algorithm is used to plan the motion path of the robotic arm. The constraints include: the distance between path points ≤ 0.5 mm; the deviation between the electric screwdriver axis and the hole axis ≤ 0.05°; and the minimum safe distance from the fixture and workpiece ≥ 10 mm.

[0080] 3) Call the corresponding electric screwdriver parameters from the preset data control according to the screw hole specifications.

[0081] The positioning compensation calculation module calculates the positioning compensation after the flipping based on the flipping posture [R, t] of the locking fixture 300, specifically as follows:

[0082] 1) Extract Euler angles (α,β,γ) from the rotation matrix R, where β is the angle about the flip axis.

[0083] 2) Read the translation vector t = [t x , t y , t z ].

[0084] The correction module, based on positioning compensation, corrects the second locking path, specifically by correcting the locking path point of the second locking component, P, based on the extracted angle β and translation vector t around the flip axis. 修正 =R(β)·P 初始+t.

[0085] This invention utilizes the coordination of a visual positioning system and a control system to perform a single visual positioning of the locking fixture 300 and the workpiece, providing locking paths for the first and second locking components at different workstation angles. The visual positioning system tracks the flipping posture of the locking fixture 300, calculates positioning compensation in real time, corrects the second locking path, and improves locking accuracy. This solves the problem of deviation in the second locking path caused by physical disturbances resulting from the flipping of the locking fixture 300, and avoids the limitation of relying on the same initial positioning for both locking operations.

[0086] like Figure 3 As shown, the present invention also provides a control method for a high-efficiency automatic screw fastening device, comprising the following steps:

[0087] S1. Grab the workpiece from the conveying mechanism and place it on the locking fixture 300 to fix the workpiece;

[0088] S2. Using a visual positioning system, identify the features and positions of screw holes on the workpiece and classify them into first screw holes and second screw holes according to specifications.

[0089] S3. Based on the characteristics and positions of the first and second screw holes, plan the locking paths of the first and second locking components respectively, and control the first locking component to perform locking of the first screw based on the first locking path;

[0090] S4. Flip the locking fixture 300, and calculate the positioning compensation after flipping based on the flipping posture of the locking fixture 300 tracked by the visual positioning system, and correct the second locking path.

[0091] S5. Control the second locking component to execute the modified second locking path to complete the locking of the second screw.

[0092] Each step is explained in detail below.

[0093] In step S1, the conveying mechanism transports the molded case circuit breaker to be processed to the designated position. Here, a gripping device such as a mechanical gripper or vacuum suction cup can be used to achieve precise handling and positioning of the workpiece. Next, the workpiece is placed on a tilting table 200 driven by a servo motor 100 and securely fixed by a locking fixture 300. The locking fixture 300 is designed to apply uniform pressure to the workpiece, preventing deformation.

[0094] In step S2, the workpiece is fixed, and the next step is to identify the screw hole features using a vision positioning system integrated above the locking fixture 300. This system includes a 3D vision module and a multispectral light source, capable of acquiring point cloud data of the workpiece surface and using a Hough circle detection algorithm combined with sub-pixel edge fitting technology to calibrate the hole center coordinates. Furthermore, structured light projection is used to measure the hole depth and tilt angle. Based on the screw hole size (e.g., M3 and M8), these holes are classified as first screw holes and second screw holes.

[0095] In step S3, the fastening path planning module in the control system generates a fastening path based on the position and direction vector of the screw holes. For the first screw holes, since they are usually located on the front side of the workpiece, the first fastening assembly can directly perform the fastening operation from a vertically downward direction. This step requires accurately calculating the alignment of the electric screwdriver tip pose with the hole axis and using the RRT* algorithm to plan the optimal motion path, ensuring that the path point spacing does not exceed 0.5mm and the deviation between the electric screwdriver axis and the hole axis is less than 0.05°.

[0096] In step S4, the rotation angle of the locking fixture 300 is 90° or 180°. When the rotation angle is 90°, the second locking component is on the side, while when the rotation angle is 180°, the second locking component is below and locked from the bottom.

[0097] During the flipping process, the visual positioning system continuously monitors and records the attitude changes of the locking fixture 300. Using the ICP algorithm, the system can update the rotation matrix and translation vector in real time, thereby calculating new positioning compensation values. These compensation values ​​are used to adjust the working path of the second locking component to adapt to the new position after flipping.

[0098] In summary, this highly efficient automatic screw fastening device and its control method significantly improve production efficiency and product quality, especially suitable for complex products requiring high-precision fastening operations, such as molded case circuit breakers. The first fastening assembly (vertically downward) and the second fastening assembly (lateral / elevation angle) work together to fasten the stationary contacts (M3-M5) and terminal blocks (M6-M8) of the molded case circuit breaker, respectively, without the need to change screwdriver bits or adjust torque. The cycle time per piece is reduced to 8-10 seconds, increasing efficiency by over 40%. The two robotic arms are positioned at 90° or 180°, with no overlap in the workspace, completely avoiding motion interference and reducing the risk of collisions.

[0099] Based on the preferred embodiments of the present invention described above, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A high-efficiency automatic screw fastening device, characterized in that, include: The machine body is equipped with a conveying mechanism for transporting the workpieces to be processed; The fixing mechanism includes a servo motor-driven tilting table, a locking fixture, and a base, used to clamp the workpiece and achieve tilting; The locking mechanism includes a first locking component and a second locking component, which are respectively configured to perform locking operations on screws of different specifications; A vision positioning system, integrated above the locking fixture, is used to acquire the hole features of the screw holes on the workpiece and track the flipping posture of the locking fixture. The system includes a main control module, a locking path planning module, a positioning compensation calculation module, and a correction module. The locking path planning module divides the screw holes on the workpiece into first screw holes and second screw holes corresponding to the first and second locking components based on the hole characteristics, and plans the first locking path and the second locking path respectively. The positioning compensation calculation module calculates the positioning compensation after flipping based on the flipping posture of the locking fixture. The correction module corrects the second locking path based on the positioning compensation. Specifically, the visual positioning system tracks the flipping posture of the locking fixture by: acquiring point cloud data of the locking fixture surface in real time; and calculating the flipping posture of the locking fixture using the ICP algorithm. Specifically, this involves aligning the current frame point cloud with the initial frame point cloud, and calculating the rotation matrix R and translation vector t, using the following formula: , where P i For the current frame point cloud, Q i Point cloud for the initial frame; The calculation of the positioning compensation specifically involves extracting Euler angles from the rotation matrix R. Where β is the angle around the flip axis; read the translation vector. , where t x t y t z These represent the translation components along the X, Y, and Z axes of the three-dimensional rectangular coordinate system, respectively. The correction of the second locking path is specifically as follows: based on the angle β and the translation vector t, according to... The second locking path point is corrected, where R(β) represents the rotation matrix about the flip axis determined by angle β, and P 初始 P represents the second locking path point planned before the flip. 修正 This represents the corresponding path point obtained after applying rotation and translation compensation.

2. The high-efficiency automatic screw fastening device according to claim 1, characterized in that: The locking fixture includes: an upper fixture, a lower fixture, and a servo electric cylinder for controlling the downward pressure of the upper fixture; The upper surface of the upper fixture is provided with a contour positioning groove that matches the workpiece locking position; Several elastic telescopic rods are provided on the opposing surfaces of the upper and lower fixtures; The lower fixture and the servo electric cylinder are disposed on the upper surface of the tilting table. The upper end of the servo electric cylinder is connected to the upper fixture, which is located directly above the lower fixture.

3. The high-efficiency automatic screw fastening device according to claim 1, characterized in that: The first locking component is located directly above the locking fixture, and the angle between the second locking component and the first locking component is the same as the flipping angle of the flipping table.

4. The high-efficiency automatic screw fastening device according to claim 1, characterized in that: The visual positioning system includes: a 3D vision module and a multispectral light source; The 3D vision module is configured as a set of industrial cameras, which are vertically mounted above the locking fixture. The multispectral light source is configured with infrared 850nm and blue light 450nm bands, and illuminates the workpiece surface at a 30° angle.

5. The high-efficiency automatic screw fastening device according to claim 1, characterized in that: The visual positioning system acquires the screw hole features on the workpiece, specifically as follows: The workpiece fixed to the locking fixture is scanned from multiple angles to obtain surface point cloud data. The two types of screw holes on the workpiece are divided into first screw holes and second screw holes, and the center coordinates, depth and tilt angle of the holes are extracted respectively. For the second screw hole, based on the preset flipping trajectory of the locking fixture, the center coordinates, depth and tilt angle parameters of the identified second screw hole are converted into the center coordinates, depth and tilt angle parameters of the flipped second screw hole.

6. A control method for a high-efficiency automatic screw fastening device, based on the high-efficiency automatic screw fastening device according to any one of claims 1-5, characterized in that, Includes the following steps: S1. Grab the workpiece from the conveyor mechanism and place it on the locking fixture to fix the workpiece; S2. Using a visual positioning system, identify the features and positions of screw holes on the workpiece and classify them into first screw holes and second screw holes according to specifications. S3. Based on the characteristics and positions of the first and second screw holes, plan the locking paths of the first and second locking components respectively, and control the first locking component to perform locking of the first screw based on the first locking path; S4. Flip the locking fixture, and calculate the positioning compensation after flipping based on the flipping posture of the locking fixture tracked by the vision positioning system, and correct the second locking path. S5. Control the second locking component to execute the modified second locking path to complete the locking of the second screw.

7. The control method for a high-efficiency automatic screw fastening device according to claim 6, characterized in that: The locking fixture can be rotated at an angle of 90° or 180°.

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