A human-machine collaborative automated adhesive application control system for aviation and its control method

Abstract

This invention provides a human-machine collaborative automated adhesive application control system and method for aviation, relating to the field of industrial robot automatic control. The robot includes a lifting platform mounted on an AGV (Automated Guided Vehicle), a robotic arm mounted on the lifting platform, an end effector mounted at one end of the robotic arm, and a vision component mounted next to the end effector. The end effector includes a single-liquid screw pump, a dispensing nozzle connected to the single-liquid screw pump, and a scraper mounted on one side of the dispensing nozzle. The single-liquid screw pump is controlled to change the total dispensing volume, dispensing speed, and backflow speed. A curved surface worktable for the aircraft fuselage to be surface-processed is positioned at a predetermined location within the movable range of the AGV. Adhesive tape is used to form a U-shaped seam and / or a straight seam on the curved surface worktable, and the vision component scans the seam. This invention can control the continuous scanning and data acquisition of the seam, adhesive application, and scraping, achieving automated processing and improving adhesive application quality and flexibility.

Description

Technical Field

[0001] This invention relates to the field of automatic control of industrial robots, and in particular to a human-machine collaborative automated adhesive application control system and its control method for aviation. Background Technology

[0002] Currently, in many assembly industries, especially in aircraft assembly, the large size and weight of aircraft parts often prevent integrated production. Therefore, the manufacturing process typically involves manufacturing each part individually and then assembling them step by step. Modern aircraft are generally composed of multiple components and materials, including aluminum alloys and composite materials. At the joints between these materials, especially at seams, sealing and adhesive techniques are required to ensure the bonding strength and durability between different materials. With innovations in materials science and coating technology, various high-performance adhesives and sealants are constantly being introduced. These materials exhibit excellent bonding performance, high-temperature resistance, and aging resistance, making the application of aircraft in high-intensity, complex environments a reality. Applying adhesive to the seams on the aircraft fuselage exterior, taking into account multiple factors such as fuselage structural strength, airtightness, corrosion resistance, and weight, is a crucial technical step, essential for ensuring the safety and reliability of the aircraft.

[0003] However, current automated methods for applying adhesive to seams on the machine body's exterior often involve: manual tape application; manual or automated adhesive application; manual scraping of adhesive; and manual inspection of the application quality. When the machine body is large, the seams are long and come in various shapes, such as straight lines, squares, and T-shapes, and are distributed across curved surfaces at different locations on the machine body. Manually holding the glue bucket to apply adhesive not only makes it difficult to precisely control the amount and speed of adhesive dispensing, as well as the continuity of application, thus making it difficult to guarantee the overall adhesive quality, but also poses certain safety risks for workers operating at higher seam locations. Summary of the Invention

[0004] Purpose of the invention: To propose a human-machine collaborative automated adhesive application control system for aviation, and further to propose a control method for the automated adhesive application robot, so as to solve the above-mentioned problems existing in the prior art.

[0005] In a first aspect, the present invention provides a human-machine collaborative aviation automated adhesive application control system, comprising: an AGV trolley, a lifting platform mounted on the AGV trolley, a robotic arm mounted on the lifting platform, an end effector mounted on one end of the robotic arm, and a vision component mounted next to the end effector.

[0006] The end effector includes a single-liquid screw pump, a dispensing nozzle connected to the single-liquid screw pump, and a scraper disposed on one side of the dispensing nozzle; the single-liquid screw pump is controlled to change the total dispensing volume, dispensing speed, and back suction speed;

[0007] The vision component includes a binocular camera and a line laser sensor; the vision component is used to identify the adhesive application position on the outer surface of the curved surface workbench of the aircraft fuselage and correct the work trajectory in real time.

[0008] The worktable for the curved surface of the aircraft fuselage to be surface-processed is set up at a predetermined position within the range that the AGV trolley can move to;

[0009] On the curved worktable, tape is used to form a U-shaped seam and / or a straight seam, and the seam is scanned using the vision component.

[0010] A second aspect of the present invention provides a control method for the aforementioned human-machine collaborative aviation automated adhesive application control system, comprising the following steps:

[0011] Calibrate the coordinate system of the end effector;

[0012] On a curved workbench, use tape to create a crisscross pattern and / or a straight line;

[0013] Establish the relative positional relationship between the end effector and the curved worktable, obtain the working area, and control the AGV to move to the working area;

[0014] When the AGV arrives at the work area, the control robot arm moves toward the seam and the vision component identifies the seam information.

[0015] Based on the seam information and the moving speed of the robotic arm, the adhesive application trajectory and dispensing pattern are calculated.

[0016] The robotic arm drives the end effector to complete the glue application;

[0017] After the adhesive is applied, the tape is manually removed, and the robotic arm drives a binocular camera to scan and check the quality of the adhesive application. If the quality of the adhesive application is found to be substandard in a certain area, the robot's pose information corresponding to that area is output, and the adhesive is manually applied.

[0018] In a further embodiment of the second aspect, establishing the relative positional relationship between the end effector and the curved surface stage specifically includes:

[0019] The cross laser emitted by the line laser sensor is dragged to illuminate the reference hole on the curved worktable. At this time, the binocular camera captures and measures the three-dimensional coordinates of multiple reference rivet heads in the robot arm base coordinate system, and calculates the relative pose between the curved worktable coordinate system and the robot arm base coordinate system.

[0020] In a further embodiment of the second aspect, the seam information is identified using a visual component, specifically including:

[0021] A line laser sensor is used to scan the seam to obtain several raw point cloud data, which includes the X and Z coordinates of each point.

[0022] All raw point cloud data were divided into 16 groups, each containing 2N points. The average x and y coordinates of the first N points were recorded as average1x and average1y; the average x and y coordinates of the last N points were recorded as average2x and average2y.

[0023] And calculate the slope for each group:

[0024] ;

[0025] By recursively calculating the slope of each group, comparing the magnitudes of the slopes in each group, and taking the maximum slope, the results are obtained. and minimum value As the point of abrupt change at both ends of the seam at that moment, the coordinates of the two points are recorded simultaneously, i.e. ( ), ( );

[0026] Calculate the coordinates of the midpoint between the two abrupt change points as the target point in the robot tool coordinate system during glue application. Its coordinates are as follows:

[0027] ;

[0028] ;

[0029] .

[0030] In a further embodiment of the second aspect, based on the seam information and the moving speed of the robotic arm, the adhesive application trajectory and adhesive dispensing pattern are calculated, specifically including:

[0031] The vector of the relative position of the line laser sensor with respect to the robotic arm along the Z-axis. The Z-axis direction serves as the coordinate system of the end effector.

[0032] Let the Z-axis direction of the robot arm's base coordinate system be taken as the Y-axis direction of the end effector's coordinate system, that is... = Then the X-axis direction of the end effector coordinate system = Find the Y-axis vector of the end effector coordinate system. Form a 3x3 rotation matrix from the three direction vectors. =[ ];

[0033] According to the rotation matrix Find the Euler angles Roll, Pitch, and Yaw, and their corresponding A, B, and C coordinates in Cartesian coordinates.

[0034] Calculate the coordinates of the midpoint of the seam in the robot's base coordinate system:

[0035] ;

[0036] Output the complete pose of the midpoint of the seam in the robot's base coordinate system. (X,Y,Z,A,B,C);

[0037] After the scan is completed, all pose information generated is imported into ROBODK software for simulation. After deleting points that deviate from the trajectory, the NC code for generating the end effector coordinate system is determined and saved as an NC file.

[0038] B-spline curve interpolation is performed on the points in the NC file to optimize the glue application trajectory.

[0039] In a further embodiment of the second aspect, the robotic arm drives the end effector to complete the adhesive application, specifically including:

[0040] The host computer reads the NC file and drives the end effector to move along the trajectory. When it moves to the first point, it triggers the glue dispensing start command, and the end effector starts dispensing glue. The glue nozzle has a glue scraper to scrape the glue. When it moves to the last point, it triggers the end command, and the end effector stops dispensing glue.

[0041] In a further embodiment of the second aspect, after the adhesive application is completed, the tape is manually removed, and a robotic arm drives a binocular camera to scan and inspect the adhesive application quality, specifically including:

[0042] In each scan profile, starting from the first point, the absolute value of the difference between all adjacent points is recorded sequentially. Calculate the difference between the absolute value of each difference and the joint depth d. ;

[0043] When the difference If the value exceeds the preset value, the adhesive application quality is deemed unqualified.

[0044] In a third aspect, the present invention provides an electronic device comprising: a processor, a memory, a communication interface, and a communication bus, wherein the processor, the memory, and the communication interface communicate with each other via the communication bus; the memory stores a plurality of executable instructions, wherein the executable instructions cause the processor to execute the control method of the human-machine collaborative aviation automated adhesive coating control system as described in the second aspect.

[0045] In a fourth aspect, the present invention provides a computer-readable storage medium storing a plurality of executable instructions which, when executed on an electronic device, cause the electronic device to perform a control method for a human-machine collaborative aviation automated adhesive coating control system as described in the second aspect.

[0046] Compared with existing technologies, the present invention has the following advantages: The present invention can automate the entire process of applying glue, scraping glue, and quality inspection of the seams on the outer surface of the machine body. Through multiple experimental verifications, the present invention can maintain a highly consistent amount and position of glue during the application process, reducing material waste and avoiding errors that may occur in manual operation, thereby improving the overall quality of the product. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the collaborative robotic arm adhesive application system in an example of the present invention.

[0048] Figure 2 This is a schematic diagram showing the connection of the robot, the line laser sensor, and the end effector in an example of the present invention.

[0049] Figure 3 This is a schematic diagram of the curved worktable in an example of the present invention.

[0050] Figure 4 This is a schematic diagram of the principle of scanning the seam using a line laser sensor in an example of the present invention.

[0051] Figure 5 This is a flowchart illustrating the control relationship in an example of the present invention.

[0052] Figure 6 This is a schematic diagram of the adhesive application process in an example of the present invention.

[0053] The labels for each item in the diagram are as follows: 1. Host computer; 2. Robot controller; 3. AGV trolley; 4. Mechanical arm; 5. Curved worktable; 5. U-shaped seam; 5. Straight seam; 5. End effector; 6. Single-liquid screw pump; 6. Binocular camera; 6. Glue scraper; 6. Line laser sensor; 6. Glue bucket; 6. Lifting platform; 7. Detailed Implementation

[0054] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid obscuring the invention.

[0055] like Figure 1This example provides a method for applying adhesive to the seams of the outer surface of a machine body using a collaborative robotic arm 4 carrying a line laser sensor 6-4. The method mainly includes a host computer 1, a robot controller 2, an AGV trolley 3, a collaborative robotic arm 4, an adhesive application table, a line laser sensor 6-4, an end effector 6, and a lifting platform 7.

[0056] like Figure 2 As shown, the line laser sensor 6-4 is mounted on the flange of the collaborative robotic arm 4 together with the end effector 6. The end effector 6 includes a single-liquid screw pump 6-1, a glue scraper 6-3, and a glue tank 6-5.

[0057] like Figure 4 As shown, adhesive is applied to the curved workbench 5 to form a U-shaped seam 5-1 and a straight seam 5-2.

[0058] like Figure 3 As shown, the line laser sensor 6-4 is scanning the seam.

[0059] As a technical solution of the present invention, a human-machine collaborative automated adhesive application method for aviation, the control relationships and processes of which are described in detail below. Figure 5 and Figure 6 The steps are as follows:

[0060] Step S1: Power on the robot, turn on the sensor power, use the teach pendant to operate the robot to scan the ceramic standard ball, process the scan data, calculate the hand-eye matrix according to the integrated calibration algorithm, and complete the hand-eye calibration of the sensor and the robot.

[0061] Step S2: Use the robot's built-in handheld four-point calibration method to complete the calibration of the end effector 6 relative to the robot's end tool coordinate system (TCP).

[0062] Step S3: Lay a thin layer of tape on the curved workbench 5, and then lay double-sided tape on top of it to create a gap of about 2-3mm to simulate a seam.

[0063] Step S4: Using ROBODK industrial robot offline programming software, import the digital models of the robot, experimental platform, sensors, screw valves and other equipment and establish their relative positions. Perform offline programming simulation on the real experimental scenario to obtain the NC code of the line scan sensor during scanning.

[0064] Step S5: Manually drag the end effector 6 to illuminate the reference hole with the cross laser emitted by the line laser sensor 6-4. At this time, the binocular camera 6-2 takes pictures and measures the three-dimensional coordinates of multiple reference rivet heads in the coordinate system of the collaborative robot arm 4. It accurately calculates the relative pose between the product position coordinate system and the position coordinate system of the glue application collaborative robot arm 4, and updates it automatically in offline programming.

[0065] Step S6: Use offline programming software to simulate the real experimental scenario and obtain the NC code of the line scan sensor during scanning.

[0066] Step S5: Connect the line laser sensor 6-4 to the host computer 1 via a signal cable, and use the ScanControlConfiguration Tools software to enable communication between the sensor and the host computer 1. Set the sensor initialization parameters such as laser exposure time, contour frequency, and points for each contour.

[0067] Step S6: Control the AGV trolley 3 to move to the predetermined processing position, and at the same time control the lifting platform 7 to reach the predetermined working height; store the offline programmed robot pose (XYZABC) NC code in a .txt file, place it in the program project working directory, and use the host computer 1 program to read the pose information in the .txt file and continuously move to these poses.

[0068] Step S7: Use the host computer program to continuously read the current pose information of the robot's end effector during the robot's movement. Set the read cycle to 100ms.

[0069] Step S8: Use the host computer program to make the sensor scan the seam to obtain the original data of the point cloud, namely the x and z coordinates of each point, and make the data collected each time processed and matched with the current robot pose information for calculation.

[0070] Step S9: Process the raw data. Each scan yields 1280 points of raw data, starting from the 41st point. Begin by recording the average of the x and y values ​​of the first 40 points for each point, denoted as average1x and average1y respectively; record the average of the x and y values ​​of the next 40 points for that point, denoted as average2x and average2y respectively, and calculate the slope at that point. Continue this process until the 600th point.

[0071] .

[0072] Step S10: Compare the slopes sequentially and take the maximum slope. and minimum value As the point of abrupt change at both ends of the seam at that moment, the coordinates of the two points are recorded simultaneously, i.e. ( ), ( ).

[0073] Step S11: Calculate the coordinates of the midpoint between these two breakpoints as the target point in the robot tool coordinate system during glue application. :

[0074] ,

[0075] ,

[0076] .

[0077] Step S12: Convert the Cartesian coordinates of the robot's end effector from step S7 to 4. Transformation matrix of 4 The hand-eye matrix relating the sensor to the robot flange Multiplying the results yields the transformation matrix of the sensor relative to the robot base. .

[0078] Step S13: Obtain the Z-axis vector of the sensor's relative position to the robot Base. The Z-axis direction, serving as the coordinate system for the adhesive application tool, ensures that the tool remains close to the normal direction of the workpiece surface during adhesive application.

[0079] Step S14: Assume the Z-axis direction of the robot's base coordinate system is taken as the Y-axis direction of the adhesive application tool's coordinate system TCP. = Then the X-axis direction of TCP = Find the Y-axis vector of TCP. The three direction vectors are used to form a 3x3 rotation matrix for TCP. =[ ].

[0080] Step S15: Calculate the Euler angles Roll, Pitch, and Yaw based on the TCP rotation matrix, which correspond to A, B, and C in Cartesian coordinates, respectively.

[0081] Step S16: Calculate the coordinates of the midpoint of the seam in the robot's base coordinate system:

[0082] .

[0083] Step S17: Output the complete pose of the seam midpoint in the robot's base coordinate system: (X,Y,Z,A,B,C).

[0084] Step S18: Import all pose information generated after scanning into ROBODK software for simulation, delete points that deviate from the trajectory, determine the NC code for TCP generation, and save it to a .txt file.

[0085] Step S19: Perform B-spline curve interpolation on the points in the NC code to optimize the glue application trajectory. The main characteristic of B-splines is that they allow the curve to change locally by adjusting the control points. Its mathematical expression is:

[0086]

[0087] In the formula, ( ) is a basis function of a k-th (k-1)th degree B-spline function. For the control points of the B-spline function, the weight factors are... Set it to 1 to bring the curve closer to the corresponding control point.

[0088]

[0089] Because B-spline curves have the property of local support, for There are at most k+1 non-zero basis functions Therefore, B-spline curves can also be represented as follows:

[0090]

[0091] The l-th derivative of the k-th degree B-spline curve is calculated using the de Boor-Cox recursive formula:

[0092]

[0093] Setting the repetition degree of the two nodes to k+1 allows the curve to pass through both the starting and ending points, thus requiring only n-1 internal nodes. The curve is then normalized using the cumulative chord length parameter method.

[0094]

[0095] in .

[0096] Step S20: Estimate the appropriate glue dispensing speed based on the seam length, width, depth and robot movement speed. The host computer 1 connects to the single-liquid screw pump 6-1 via RS485 communication program to set parameters such as glue dispensing volume, glue dispensing speed and back suction speed.

[0097] Step S21: The host computer 1 reads the NC file and drives the robot end effector to move along the trajectory. When it moves to the first point, it triggers the glue dispensing start command and the end effector 6 starts dispensing glue. The glue nozzle has a glue scraper 6-3 to scrape the glue. When it moves to the last point, it triggers the end command and the end effector 6 stops dispensing glue.

[0098] Step S22: Peel off the surface layer of the tape and manually observe the adhesive application effect to see if there is any obvious glue breakage or overflow.

[0099] Step S23: The robot carrying the sensor end scans the seam again, that is, runs the NC code in step 6 to detect the adhesive quality.

[0100] Step S24: During the scanning process, the seam is detected. In each scan profile, starting from the first point, its Z coordinate is... Compare with the next point The absolute value of the difference And so on, record the difference between all adjacent points. Calculate the absolute value of the difference between each value and the seam depth d. Assuming the seam depth is 3.5mm, the following possibilities may occur:

[0101]

[0102] Among them, when If the adhesive application quality is deemed unqualified, the possible causes include: adhesive breakage, adhesive leakage, and adhesive overflow. Further assessment is needed to determine the specific situation.

[0103] Step S25: During the scanning process, the seam is inspected, and the X coordinates of the points at the two edges of the seam after adhesive application are calculated to obtain the width of the seam. Assuming the seam width is 3mm, the following possibilities may occur.

[0104]

[0105] When the glue application quality is not up to standard, the robot outputs its current pose information and saves the record for easy retrieval of the location later. If glue breaks or leaks, manual glue replenishment is required; if glue overflows, manual glue scraping is required.

[0106] The control method disclosed in the above embodiments can be embedded in a field system by being written as executable code. The executable code runs in the field system as software, and the software can be written to a computer-readable storage medium. More specific examples of computer-readable storage media in this embodiment may include, but are not limited to: electrical connections with one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the above.

[0107] Computer-readable storage media may include data signals propagated in baseband or as part of a carrier wave, carrying readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A readable signal medium may also be any readable medium other than a readable storage medium, capable of sending, propagating, or transmitting a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0108] As described above, although the invention has been shown and described with reference to specific preferred embodiments, it should not be construed as limiting the invention itself. Various changes in form and detail may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A control method for a human-machine collaborative automated adhesive application control system for aviation, characterized in that, Includes the following steps: Calibrate the coordinate system of the end effector; On a curved workbench, use tape to create a crisscross pattern and / or a straight line; Establish the relative positional relationship between the end effector and the curved worktable, obtain the working area, and control the AGV to move to the working area; When the AGV arrives at the work area, the control robot arm moves toward the seam and the vision component identifies the seam information. Based on the seam information and the robotic arm's movement speed, the adhesive application trajectory and dispensing pattern are calculated, specifically including: The vector of the relative position of the line laser sensor with respect to the robotic arm along the Z-axis. The Z-axis direction serves as the coordinate system of the end effector. Let the Z-axis direction of the robot arm's base coordinate system be taken as the Y-axis direction of the end effector's coordinate system, that is... = Then the X-axis direction of the end effector coordinate system = Find the Y-axis vector of the end effector coordinate system. Form a 3x3 rotation matrix from the three direction vectors. =[ ]; According to the rotation matrix Find the Euler angles Roll, Pitch, and Yaw, and their corresponding A, B, and C coordinates in Cartesian coordinates. Calculate the coordinates of the midpoint of the seam in the robot's base coordinate system: ； In the formula, The transformation matrix is ​​used to convert the Cartesian coordinates of the robot's end effector into a 4×4 matrix. The hand-eye matrix represents the relationship between the sensor and the robot flange; This is the target point in the robot tool coordinate system during glue application; Output the complete pose of the midpoint of the seam in the robot's base coordinate system. (X,Y,Z,A,B,C); After the scan is completed, all pose information generated is imported into ROBODK software for simulation. After deleting points that deviate from the trajectory, the NC code for generating the end effector coordinate system is determined and saved as an NC file. Perform B-spline curve interpolation on the points in the NC file to optimize the glue application trajectory; The robotic arm drives the end effector to complete the glue application; After the adhesive is applied, the tape is manually removed, and the robotic arm drives a binocular camera to scan and check the quality of the adhesive application. If the quality of the adhesive application is found to be substandard in a certain area, the robot's pose information for that area is output, and the adhesive is manually applied.

2. The control method of the human-machine collaborative aviation automated adhesive application control system according to claim 1, characterized in that, Establishing the relative positional relationship between the end effector and the curved surface table specifically includes: The cross laser emitted by the line laser sensor is dragged to illuminate the reference hole on the curved worktable. At this time, the binocular camera captures and measures the three-dimensional coordinates of multiple reference rivet heads in the robot arm base coordinate system, and calculates the relative pose between the curved worktable coordinate system and the robot arm base coordinate system.

3. The control method of the human-machine collaborative aviation automated adhesive application control system according to claim 1, characterized in that, The visual components are used to identify seam alignment information, specifically including: A line laser sensor is used to scan the seam to obtain several raw point cloud data, which includes the X and Z coordinates of each point. All raw point cloud data were divided into 16 groups, each containing 2N points. The average x and y coordinates of the first N points were recorded as average1x and average1y; the average x and y coordinates of the last N points were recorded as average2x and average2y. And calculate the slope for each group: ； By recursively calculating the slope of each group, comparing the magnitudes of the slopes in each group, and taking the maximum slope, the results are obtained. and minimum value As the two abrupt change points at the two ends of the seam, the coordinates of the two points are recorded simultaneously, i.e. ( ), ( ); Calculate the coordinates of the midpoint between the two abrupt change points as the target point in the robot tool coordinate system during glue application. Its coordinates are as follows: ； ； 。 4. The control method of the human-machine collaborative aviation automated adhesive application control system according to claim 1, characterized in that, The robotic arm drives the end effector to complete the adhesive application, specifically including: The host computer reads the NC file and drives the end effector to move along the trajectory. When it moves to the first point, it triggers the glue dispensing start command, and the end effector starts dispensing glue. The glue nozzle has a glue scraper to scrape the glue. When it moves to the last point, it triggers the end command, and the end effector stops dispensing glue.

5. The control method of the human-machine collaborative aviation automated adhesive application control system according to claim 1, characterized in that, After the adhesive is applied, the tape is manually removed, and a robotic arm drives a binocular camera to scan and inspect the adhesive application quality, specifically including: In each scan profile, starting from the first point, the absolute value of the difference between all adjacent points is recorded sequentially. Calculate the difference between the absolute value of each difference and the joint depth d. ; When the difference If the value exceeds the preset value, the adhesive application quality is deemed unqualified.

6. An electronic device, characterized in that, include: The processor, memory, communication interface, and communication bus are provided, wherein the processor, memory, and communication interface communicate with each other via the communication bus. The memory is used to store a plurality of executable instructions, which cause the processor to execute the control method of the human-machine collaborative aviation automated adhesive coating control system as described in any one of claims 1 to 5.

7. A computer-readable storage medium, characterized in that, The storage medium stores a plurality of executable instructions, which, when executed on the electronic device, cause the electronic device to perform the control method of the human-machine collaborative aviation automated adhesive coating control system as described in any one of claims 1 to 5.

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