Collaborative robot-based detection method for in-place installation of double interlocking sheets of disc parts

Abstract

The invention relates to the field of visual inspection in the disc part assembling process, and provides a method for detecting in-place installation of double interlocking pieces of disc parts based on a collaborative robot. The method specifically comprises the steps that firstly, a robot moves to the position over a servo assembly base, a short-focus lens camera is adopted to integrally photograph a disc part, a hole position deviation angle alpha is calculated according to 16 fixing hole positions distributed in the circumferential direction, and the servo assembly base is controlled to automatically rotate by the deviation angle alpha; as the angle positions of the circumferential fixing holes of the disc parts are in one-to-one correspondence with the angle positions of the double interlocking pieces, the sampling positions of the double interlocking pieces are fixed by rotating the deviation angle alpha; a robot is moved to a sampling position at the circumferential edge of a disc part, and a telephoto lens camera is adopted to irradiate the position of a double-interlocking piece, so that a group of complete double-interlocking piece image acquisition is realized; complete image acquisition of eight groups of double-interlocking sheets in the circumferential direction is realized by controlling the servo assembly seat to rotate in a circle in an eight-indexing manner; by labeling and training various lock plate sample conditions, whether the double interlocking plates of the disc parts are installed in place or not is judged.

Description

Technical Field

[0001] The invention relates to the field of visual detection in the assembly process of disc parts, in particular to a method for detecting whether circumferential double interlocking sheets of disc parts are installed in place. Background Art

[0002] The existing assembly process of disc parts involves the installation and locking operations of eight sets of circumferential double interlocking plates. The double interlocking plates are bent and tightened to achieve fixation with matching bolts, thereby avoiding loosening of the locking bolts and achieving firm fixation of the axial components of the disc parts.

[0003] Since the double interlocking plates are located in the lower area of ​​the disc-like parts and are evenly distributed at multiple points in the circumferential direction, it is not convenient for the operator to install and check them. Usually, only one person performs the locking and inspection work of the double interlocking plates. The locking situation cannot be effectively counted, and the locking degree cannot be considered.

[0004] It is very necessary to realize the effective detection of the installation of double interlocking plates, so as to ensure the effective locking of key locking components. Summary of the invention

[0005] Aiming at the problem of whether the double interlocking plates of disk parts are installed in place, the present invention provides a visual inspection method based on a collaborative robot combined with a servo assembly seat. By matching two cameras with long and short focal length lenses, the robot is controlled to perform image acquisition at different positions of the disk parts, and a deep learning algorithm is used to realize the inspection of whether multiple double interlocking plates of the disk parts are installed in place.

[0006] The technical solution adopted by the present invention to achieve the above-mentioned purpose is:

[0007] A detection device for installing double interlocking plates of disc parts based on a collaborative robot comprises: a six-axis collaborative robot, a visual inspection tooling is provided at the end of the robot, a visual acquisition system is provided on the visual inspection tooling, and a servo assembly seat for placing the disc parts to be tested.

[0008] The visual acquisition system is composed of two area array cameras and two annular light sources. The two area array cameras are respectively arranged at the two ends of the visual inspection tooling. The area array cameras are surrounded by annular light sources. The two area array cameras are respectively a telephoto lens camera and a short-focus lens camera.

[0009] The disc-like part to be tested has 16 fixing holes symmetrically distributed around the circumference, and the upper and lower parts of the disc-like part to be tested are connected and fixed by 16 bolts. Double interlocking plates cover the ends of the bolts and are locked in the bolt grooves. Every two holes correspond to a set of double interlocking plates.

[0010] It also includes a PLC control system for controlling the movement of the robot and the operation of the visual acquisition system.

[0011] It also includes industrial computers and displays, including:

[0012] The industrial computer is used to obtain the test results and send the test results to the PLC control system and the display;

[0013] The display is used to display the detection results.

[0014] A method for detecting whether a double interlocking piece of a disk-type part is installed in place based on a collaborative robot comprises the following steps:

[0015] 1) Fix the disk parts to be tested to the servo assembly seat and lock all double interlocking plates;

[0016] 2) The robot automatically moves to the top of the disc-like part to be tested, turns on the annular light source of the short-focus lens, and collects images of 16 fixed holes through the short-focus lens camera;

[0017] 3) Calculate the deviation angle α of 16 circumferential hole positions according to the image, and turn off the annular light source of the short-focus lens;

[0018] 4) Control the servo assembly seat to drive the disc-like parts to be tested to rotate an angle of α;

[0019] 5) The robot moves to the sampling position at the circumferential edge of the disc-like part to be tested, so that the telephoto lens is at the same height as the disc-like part to be tested, the telephoto lens camera is aimed at the position of the double interlocking piece, and the counting variable count is cleared;

[0020] 6) Turn on the annular light source of the telephoto lens, shoot the double interlocking piece through the telephoto lens camera, count the variable count+1, and at the same time detect whether the double interlocking piece at the current position is locked in place;

[0021] 7) The industrial computer obtains and records the test results, sends a test completion signal to the PLC control system, and the servo assembly seat drives the disc parts to rotate 45 degrees and move to the next double interlocking position;

[0022] 8) Loop steps 6) to 7) until the counting variable count>8, then turn off the annular light source of the telephoto lens, move the robot back to its original position, and the industrial computer summarizes the detection results of all double interlocking pieces and displays them on the display interface.

[0023] The following steps are also included:

[0024] Confirm the test results, recheck the locking pieces that are not flattened or locked according to the serial number, flatten and lock them, and re-test.

[0025] The present invention has the following beneficial effects and advantages:

[0026] 1. Automatically detect whether the double interlocking pieces are installed in place, and the detection conclusion is more real and effective.

[0027] 2. Use automated methods to conduct testing, ensuring testing process and consistency.

[0028] 3. The degree of locking can be expanded by training different samples, so that the degree of locking can be determined.

[0029] 4. Completed the image acquisition of all double interlocking pieces to make product assembly traceable. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Provide a layout diagram for the system composition;

[0031] Figure 2 It is a top view of the disc parts (including 16 fixing holes);

[0032] Figure 3 Schematic diagram of eight sets of double interlocking pieces for moving deviation angle sampling;

[0033] Figure 4 A schematic diagram of specific implementation steps. DETAILED DESCRIPTION

[0034] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0035] The system of the present invention comprises the following components:

[0036] 1) Six-axis collaborative robot

[0037] 2) Visual inspection tooling

[0038] 3) Robot column

[0039] 4) Visual acquisition system (dual cameras)

[0040] 5) Disk parts to be tested

[0041] 6) Servo assembly seat

[0042] 7)PLC control system

[0043] 8) Industrial computers and displays

[0044] like Figure 1As shown, the six-axis collaborative robot is equipped with a visual inspection tooling, and two cameras and matching annular light sources are symmetrically installed on both sides of the tooling. The area array camera 1 and the annular light source 1 are long-focus lens acquisition systems to achieve the acquisition of local clear images, which are used to acquire double interlocking plates in the present invention; the area array camera 2 and the annular light source 2 are short-focus lens acquisition systems to achieve the acquisition of the global overall disk image, which are used to acquire the 16 hole position information of the disk circumference in the present invention. The robot is fixed to the robot column, and by moving the robot with a servo assembly seat, image acquisition of most positions of disk parts on the assembly seat can be achieved.

[0045] like Figure 2 As shown in the figure, the disc-like parts to be tested have 16 fixed holes symmetrically distributed in the circumferential direction. Since there is no angular matching relationship between the disc-like parts and the assembly seat, but the double interlocking pieces have a fixed corresponding relationship with the 16 holes, two holes correspond to a set of double interlocking pieces. Therefore, the robot is moved to the top of the assembly seat to collect images of the 16 holes, that is, the dotted hole positions in the figure. By comparing with the standard hole positions (solid lines), the deviation angle α of this installation can be obtained. The deviation angle α is moved by the servo assembly seat to achieve precise compensation. When the robot collects the image of the double interlocking pieces, it can be moved to the fixed sampling position to achieve a complete image collection of a set of double interlocking pieces.

[0046] like Figure 3 As shown, when the image of the double interlocking sheet is captured before compensation, the viewing angle in the camera 1 is the dotted line area in the figure. When the servo assembly seat rotates and moves according to the deviation angle α, the viewing angle in the camera 1 becomes the solid line area in the figure, thereby realizing the complete image capture of the double interlocking sheet.

[0047] like Figure 3 As shown, the sum of the deviation angles α and β is a fixed 1 / 16 circle angle, i.e., α+β=22.5°, and the viewing angle range of the camera 1 is a fixed 1 / 8 circle angle of a set of double interlocking plates (two holes), i.e., 45°. By moving the deviation angle α, the robot can be aligned in obtaining the viewing angle of the double interlocking plates, and by further rotating the fixed index of the servo assembly seat, the complete image acquisition of all double interlocking plates can be achieved.

[0048] The locking plate is in a tilted state before installation, and is perpendicular to the plane of the nut to be locked. The locking operation of the double interlocking plate is completed by flattening the locking plate and punching the middle part of the locking plate into the groove of the nut. Figure 3 As shown in the shaded part of each small trapezoid, No. 5 is a lock plate that is flattened but not locked; No. 8 is a lock plate that is tilted and not flattened. Since there are three types of samples: not flattened, flattened but not locked, and locked properly, a deep learning algorithm is used to collect sample libraries of various situations, label them, train them, generate a recognition library, and finally realize the locking judgment of all double interlocking plates.

[0049] The specific operation process of the double interlocking plate installation detection of the disc parts is as follows: Figure 4 As shown:

[0050] 1. Fix the disc parts to the servo assembly seat and lock all double interlocking plates;

[0051] 2. Select and issue the double interlocking piece detection task and start it through the host computer interface;

[0052] 3. The robot automatically moves to the top of the disc-like parts to look down at the parts, turns on the ring light source 2, and takes pictures with the short-focus lens camera to achieve image acquisition at 16 fixed holes;

[0053] 4. Calculate the deviation angle α of 16 circumferential hole positions and turn off the annular light source 2;

[0054] 5. Control the servo assembly seat to drive the disc parts to rotate at an angle of α

[0055] 6. The robot moves to the sampling position at the circumferential edge of the disc-like part, aims the telephoto lens camera at the position of the double interlocking piece, and clears the counting variable count;

[0056] 7. Turn on the ring light source 1, execute the telephoto lens camera to take pictures, and count the variable count+1;

[0057] 8. Identify whether the current double interlocking piece is locked in place;

[0058] 9. The industrial computer obtains and records the test results and sends a test completion signal to the control system;

[0059] 10. The servo assembly seat drives the disc parts to rotate 45 degrees and move to the next double interlocking piece position;

[0060] 11. Loop through steps 7-10 until the count variable count>8;

[0061] 12. When count>8, the telephoto lens camera has just taken 8 photos and completed the visual inspection of all 8 sets of double interlocking pieces. At this time, light source 1 is turned off and the robot moves back to its original position;

[0062] 13. The industrial computer summarizes the test results of all double interlocking pieces and displays them on the display interface;

[0063] 14. The operator confirms the test results, rechecks the locking pieces that are not flattened or locked according to the serial numbers, flattens and locks them, and retests.

[0064] The double interlocking piece installation detection system of the present invention can fully guarantee the detection process and detection consistency, and the detection conclusion is more real and effective. All images in the detection process can be saved, so that the components after product assembly are still traceable. The deep learning visual inspection method is used to make qualified judgments on the assembly in place. By supplementing a large number of samples of various degrees, not only can a simple "right or wrong" judgment be given, but also a range judgment of 0-1 can be given on the locking degree of the installation in place. It is a new attempt to transform and upgrade the assembly into digitalization, informatization, and intelligence.

Claims

1. A detection device for the installation of double interlocking plates of disc parts based on a collaborative robot, characterized in that: include: A six-axis collaborative robot with a visual inspection tooling at the end of the robot. The visual inspection tooling is equipped with a visual acquisition system and also includes a servo assembly seat for placing disc-type parts to be tested.

2. According to claim 1, a detection device for detecting whether the double interlocking plates of disc parts are installed in place based on a collaborative robot is characterized in that: The visual acquisition system is composed of two area array cameras and two annular light sources. The two area array cameras are respectively arranged at the two ends of the visual inspection tooling. The area array cameras are surrounded by annular light sources. The two area array cameras are respectively a telephoto lens camera and a short-focus lens camera.

3. According to claim 1, a detection device for detecting whether the double interlocking plates of disc parts are installed in place based on a collaborative robot is characterized in that: The disc-like part to be tested has 16 fixing holes symmetrically distributed around the circumference, and the upper and lower parts of the disc-like part to be tested are connected and fixed by 16 bolts. Double interlocking plates cover the ends of the bolts and are locked in the bolt grooves. Every two holes correspond to a set of double interlocking plates.

4. According to claim 1, a detection device for detecting whether the double interlocking plates of disc parts are installed in place based on a collaborative robot is characterized in that: It also includes a PLC control system for controlling the movement of the robot and the operation of the visual acquisition system.

5. The detection device for detecting whether the double interlocking plates of disc parts are installed in place based on a collaborative robot according to claim 1, characterized in that: It also includes industrial computers and displays, among which: The industrial computer is used to obtain the test results and send the test results to the PLC control system and the display; The display is used to display the detection results.

6. The method for detecting whether the double interlocking plates of disk parts are installed in place based on a collaborative robot according to claim 1 is characterized in that: The following steps are involved: 1) Fix the disk parts to be tested to the servo assembly seat and lock all double interlocking plates; 2) The robot automatically moves to the top of the disc-like part to be tested, turns on the annular light source of the short-focus lens, and collects images of 16 fixed holes through the short-focus lens camera; 3) Calculate the deviation angle α of 16 circumferential hole positions according to the image, and turn off the annular light source of the short-focus lens; 4) Control the servo assembly seat to drive the disc-like parts to be tested to rotate an angle of α; 5) The robot moves to the sampling position at the circumferential edge of the disc-like part to be tested, so that the telephoto lens is at the same height as the disc-like part to be tested, the telephoto lens camera is aimed at the position of the double interlocking piece, and the counting variable count is cleared; 6) Turn on the annular light source of the telephoto lens, shoot the double interlocking piece through the telephoto lens camera, count the variable count+1, and at the same time detect whether the double interlocking piece at the current position is locked in place; 7) The industrial computer obtains and records the test results, sends a test completion signal to the PLC control system, and the servo assembly seat drives the disc parts to rotate 45 degrees and move to the next double interlocking position; 8) Loop steps 6) to 7) until the counting variable count>8, then turn off the annular light source of the telephoto lens, move the robot back to its original position, and the industrial computer summarizes the detection results of all double interlocking pieces and displays them on the display interface.

7. The method for detecting whether the double interlocking plates of disk parts are installed in place based on a collaborative robot according to claim 6 is characterized in that: The following steps are also included: Confirm the test results, recheck the locking pieces that are not flattened or locked according to the serial number, flatten and lock them, and re-test.

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