A robot intelligent assembly system

Abstract

The present invention discloses a robot intelligent assembly system, the system includes a first four-axis industrial robot, a second four-axis industrial robot, an assembly unit, a photographing unit, a gluing unit and a software control system. The assembly unit is located at the center of the system, the first four-axis industrial robot and the second four-axis industrial robot are separated on both sides of the assembly unit, and the assembly unit cooperates with the first and second four-axis industrial robots according to the instructions of the software control system to complete the mechanical assembly operations of various parts of the product; the photographing unit takes multi-directional photos of the product according to the instructions of the software control system; the gluing unit is controlled by PLC to achieve stable glue output; the software control system is used to streamline the assembly steps through program compilation according to the process flow. The present invention adds a secondary identification and positioning function to ensure the accurate insertion of the low-noise amplifier module pins and the microstrip printed circuit board, realizes automatic management and control, and greatly improves production efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of microwave electronic product assembly, and in particular relates to a robot intelligent assembly system. Background Art

[0002] The current status of aerospace electronic product manufacturing is that the production process and manufacturing methods are still relatively backward, manual operation and manual coordination and command are still dominant, and the promotion and application of advanced manufacturing systems are insufficient; the manufacturing process data collection, storage, organization and analysis capabilities based on information technology have not yet been effectively established.

[0003] Taking microstrip antenna electronic products as the entry point, we use intelligent and automated assembly technology to greatly improve production efficiency while improving product quality and ensuring batch processing consistency, reduce dependence on operator skill levels and the number of personnel, and reduce production costs. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a robot intelligent assembly system, which utilizes industrial robots to realize automated mechanical assembly of microstrip antenna electronic products, and realizes assembly parameter quantification, recording and feedback functions, full-process multimedia recording functions and automatic classification and storage of assembly data packets through a combination of software and hardware.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] A robot intelligent assembly system, the system comprising a first four-axis industrial robot, a second four-axis industrial robot, an assembly unit, a photographing unit, a gluing unit and a software control system;

[0007] The assembly unit is located at the center of the assembly system, the first four-axis industrial robot and the second four-axis industrial robot are separated on both sides of the assembly unit, and the installation flange centers of the two robots are at the same distance from the center of the assembly unit. The assembly unit is used to cooperate with the first and second four-axis industrial robots to complete the mechanical assembly operations of various parts of the product according to the instructions of the software control system;

[0008] The first four-axis industrial robot is an assembly robot, and its arm is equipped with the first top vision CCD (Chinese name "photosensitive coupling device", which is a semiconductor device that converts light images into electronic signals), intelligent grippers and component suction nozzles, and can achieve 270 degrees in the circumferential direction. The rotation inside is used to select the component picking method according to the instructions of the software control system. The first top vision CCD is combined with the bottom vision CCD to realize the precise alignment and installation of components by using image acquisition, analysis and processing technology;

[0009] The second four-axis industrial robot is a screw-mounted robot, which is equipped with a second top vision CCD and an intelligent electric screwdriver on its arm and can achieve 270 degrees in the circumferential direction. The rotation inside is used to carry the corresponding intelligent electric screwdriver to the specified position to suck the screw according to the command of the software control system, and then move to the glue coating unit to apply thread glue. The second top visual CCD is combined with the bottom visual CCD to realize the alignment installation of the screw by using image acquisition, analysis and processing technology, and then apply torque to the screw to lock it according to the command of the software control system;

[0010] The photographing unit is located at the lower side of the first four-axis industrial robot. When the first four-axis industrial robot picks up the product and places it on the rotating platform, the photographing unit takes multi-directional photographs of the product according to the instructions of the software control system and cooperates with the first top visual CCD of the first four-axis industrial robot to use OCR optical character recognition technology to complete automatic classification and storage of multimedia photos.

[0011] The gluing unit is located below the assembly unit and includes two glue cylinders, each of which contains different glue liquids. When the second four-axis industrial robot picks up a screw of corresponding specification and moves to the top of the specified glue cylinder according to the instruction of the software control system, the quantitative application of thread glue is achieved by controlling the height of the screw penetrating into the glue needle.

[0012] The software control system is used to provide instructions to the controllers in the first and second four-axis industrial robots and the intelligent electric screwdriver in the robot intelligent assembly system, so that they drive the first and second four-axis industrial robots and the intelligent electric screwdriver to complete parts picking, installation, screw locking, abnormal state monitoring, alarm, and feedback operations; and cooperate with the first and second four-axis industrial robots and the camera unit to complete the automatic classification and storage of data reports and multimedia photos.

[0013] The beneficial effects of the present invention are:

[0014] The intelligent grippers and component suction nozzles in the first four-axis industrial robot are made of POM material with good wear resistance and toughness; the inner side of the flip grippers in the flipping mechanism of the assembly unit is coated with rubber. The material selection and structural design of the above parts that come into contact with product parts effectively avoid damage to the appearance of product parts during operation.

[0015] Top vision CCD and bottom vision CCD are introduced, and image acquisition, analysis and processing technology are used to obtain key data such as the pixel position of the center point of the component and the relative value of the device angle. The above data are transformed into coordinates to accurately realize the alignment and installation of components and screws. In addition, a secondary identification and positioning function is added to ensure the accurate insertion of the low-noise amplifier module pins and the microstrip printed circuit board.

[0016] The material placement area adopts a detachable tray structure, and the material placement tray can be adaptively changed according to the product size to meet the use requirements of products of different specifications; in addition, the component placement platform in the assembly unit adopts an embedded circular load-bearing structure design, which can adapt to the loading of products of various sizes and shapes by adding a lining structure that matches the product's outer dimensions. The above design ideas increase the versatility and adaptability of the present invention.

[0017] The OCR optical character recognition technology is used in conjunction with the software control system to realize the automatic classification and storage of high-definition multimedia photos and assembly data reports of the entire production process, realize automatic management and control, and greatly improve production efficiency.

[0018] The software control system command compilation is used to accurately control the glue coating unit to discharge glue stably, and the quantitative coating of thread glue is achieved by controlling the height of the glue discharge needle of the screw. Automated means are used to implement precise quantitative control of the glue coating process.

[0019] The design method of full-process automation of mechanical assembly greatly improves production efficiency, avoids the reduction of product quality consistency due to differences in the operating levels of skilled personnel, and focuses on developing in the direction of intelligent and automated production. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a plan layout diagram of the robot intelligent assembly system of the present invention;

[0021] Figure 2 This is a three-dimensional rendering of the robot intelligent assembly system of the present invention.

[0022] Reference numerals:

[0023] 1-Assembly robot, 2-Screw assembly robot, 3-Photographing unit, 4-First top vision CCD, 5-Assembly unit, 6-Material placement area, 7-Combination screw feeding unit, 8-Countersunk screw feeder, 9-Intelligent electric screwdriver, 10-Bottom vision CCD, 11-Gluing unit. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0025] The present invention relates to a robot intelligent assembly system, which comprises two four-axis industrial robots, a set of assembly units, a set of photographing units, a set of gluing units and a set of software control system.

[0026] The robot intelligent assembly system has two four-axis industrial robots, one of which is an assembly robot 1 and the other is a screw assembly robot 2. Before the formal operation, the parts, standard screw parts and thread glue of the product to be assembled are placed in the material placement area 6, countersunk screw feeder 8, combination screw feeding unit 7 and glue coating unit 11 in the specified installation direction. Then enter the software operation interface, select the identity and log in, select the model of the product to be assembled, the assembly quantity, the starting assembly sequence number and the process flow, and click "OK" to start the formal assembly operation after confirming that the above information is correct.

[0027] The two four-axis industrial robots can achieve 270 degrees in the circumferential direction In terms of layout, the first four-axis industrial robot and the second four-axis industrial robot are separated on both sides of the assembly unit, and the distance between the center of the mounting flange of the two robots and the center of the assembly unit is the same. The arm of the assembly robot 1 is equipped with an intelligent gripper and a component suction nozzle (the gripping force of the intelligent gripper is 3N). 5N, maximum load 50g; component suction nozzle maximum load 2kg), used to complete the grasping and suction of components, and cooperate with the arm lifting mechanism to complete the placement of components. Considering that the surface of metal structural parts is smooth and large in size after painting, it is easy to fall during grasping and the common clamping jaws are compatible with a small size range. Therefore, the picking is completed by suction nozzle, and the picking of parts with rough surfaces and large mass such as microstrip printed circuit boards and low-noise amplifier modules is carried out by clamping jaws. The screw-mounting robot 2 is equipped with an intelligent electric screwdriver to the designated position countersunk screw feeder 8 or the combination screw feeding unit 7 to suck the screws and move them to the gluing unit 11 for thread glue coating. Finally, the screws are screwed into the corresponding mounting holes according to the specified screw-mounting sequence and torque is applied to lock them.

[0028] Product material placement areas are set in the upper and lower halves of the assembly robot 1 to facilitate the assembly robot 1 to pick up the parts to be assembled; 5 countersunk screw feeders 8 and combined screw loading units 7 are set in the upper and lower halves of the screw assembly robot 2 to facilitate the screw assembly robot 2 to pick up screw fasteners, and 4 intelligent electric screwdrivers 9 are set in the area on the same axis as the screw assembly robot 2 for screw locking operations of different specifications.

[0029] The assembly unit 5 is located in the center of the system. When the assembly robot 1 picks up the parts and takes photos, it is placed in the assembly unit 5. Since the first and second top vision CCDs 4 are respectively mounted on the two four-axis industrial robot arms, they are combined with the bottom vision CCD 10 on the work surface of the assembly unit 5 to cooperate with the assembly robot 1 and the screw assembly robot 2 to realize the product thread hole positioning and position correction of each part, and the software control system is relied on to compile the program to realize the alignment installation of the parts. In addition, a flipping mechanism is designed and installed on both sides of the assembly unit 5. When flipping, the two side clamps are pressed against the product and the first servo motor drives the clamps to complete the plane flipping of the product.

[0030] The camera unit 3 is located below the assembly robot 1 and is mainly composed of a high-resolution color camera, a camera bracket and a rotating platform. According to the process requirements and software compilation, the whole process of product production can be realized directly facing and 45 The assembly robot 1 has a multimedia photo recording function. During operation, the assembly robot 1 grabs the product and puts it on the rotating platform. The second servo motor drives the camera bracket to move to the rotating platform position to take multimedia photos of the product.

[0031] The glue coating unit 11 is located below the assembly unit, and is mainly composed of a glue dispensing controller, a glue coating cylinder, and a glue dispensing needle. The glue dispensing controller is controlled by a PLC, and is also equipped with RS-232 communication. It receives software control system instructions through I / O signal control or serial communication and feedbacks information to control the stable glue dispensing of the front end. The glue coating cylinder is vertically fixed to the bottom plate of the equipment by a fixed bracket, and the glue is discharged by controlling the up and down movement of the internal piston by air pressure. The glue dispensing accuracy can reach 0.01mL. The glue coating cylinder and the glue dispensing needle are both consumables, with low cost and easy replacement.

[0032] The software control system is a customized design. At the technical level, the assembly steps are streamlined through program compilation according to the process flow, and the key information of the product assembly process (such as assembly quantity, step start, completion time, tightening torque value feedback, etc.) is output and fed back in the form of reports, and abnormal conditions are promptly alarmed. The intelligent electric screwdriver is configured to output the actual number of tightening circles and tightening torque to the software for real-time monitoring. The intelligent electric screwdriver can flexibly adjust the speed and tightening torque when the screw is locked. At the same time, the software establishes communication with the intelligent electric screwdriver controller, monitors the locking data of each screw, and intelligently judges faults such as buckling to ensure that efficiency and accuracy meet high-performance requirements. At the management level, the software control system sets login permissions for different personnel. For example, administrator permissions can add and reduce the number of users, change and release user permissions, adjust process parameters, and operate the system; debugger permissions can adjust process parameters and operate the system; operator permissions can only operate the system, and login permissions are set to facilitate factory management.

[0033] During assembly, the assembly robot 1 picks up the parts and takes photos, and then places them in the assembly unit 5. The assembly robot 1 and the screw-mounting robot 2 are respectively equipped with the first and second top visual CCD4 to take photos of the lower-layer parts or the top surface of the threaded hole to collect identification and positioning to obtain the center point coordinates of the parts or threaded holes, and then select a reference point according to the surface features of the parts to determine the placement angle of the lower-layer parts by calculating the angle and position coordinate offset between the center point coordinates and the reference point. Then the assembly robot 1 and the screw-mounting robot 2 pick up the upper-layer parts or screws and move them to the top of the bottom visual CCD10 and obtain the center point coordinates of the bottom surface of the parts or screws with the help of the photos taken by them. For the alignment and installation of parts, it is necessary to select the position corresponding to the reference point of the lower-layer parts on the bottom surface of the upper-layer parts as the reference point to calculate the angle and position coordinate offset between the center point coordinates and the reference point, so as to determine the placement angle of the upper-layer parts; and for the alignment of the screws and the threaded holes, it is only necessary to collect the center point coordinates of the screws and the threaded holes. According to the above data, the nine-point coordinate calibration is first performed, and the current pixel coordinates are translated, rotated, scaled, and other operations are performed to generate an affine matrix to realize the conversion of the relative position between the pixel coordinate system and the world coordinate system of the assembly robot 1 and the screw-mounting robot 2. Then, the hand-eye calibration is used to obtain the transformation relationship between the terminal coordinate system of the assembly robot 1 and the screw-mounting robot 2 and the camera coordinate system, and finally the unique correspondence between the image coordinate system and the working point coordinates of the assembly robot 1 and the screw-mounting robot 2 is realized. When the first and second top vision CCD4 and the bottom vision CCD10 recognize the same coordinates, the precise alignment and installation of parts and screws can be completed directly; on the contrary, when the first and second top vision CCD4 and the bottom vision CCD10 recognize the same coordinates, it is necessary to calculate the difference between the angle and axial position of the two coordinates, and the assembly robot 1 and the screw-mounting robot 2 complete the angle and axial position adjustment to make the two coordinates correspond to each other. In addition, since the clearance between the pin of the low-noise amplifier module and the socket of the microstrip printed circuit board is only 0.2mm 0.4mm, for this purpose, the center point and angle of the low noise amplifier module pin are identified through the first top vision CCD, and then the position of the root of the low noise amplifier module pin is obtained according to the CAD data. The first four-axis industrial robot equipped with the first top vision CCD4 moves to the root of the low noise amplifier module pin to take a photo to find the pixel position of the low noise amplifier module pin, and the top offset of the low noise amplifier module pin is obtained by calculation. During assembly, only this offset needs to be added to the coordinate position of the identified center point to achieve accurate alignment and installation of the low noise amplifier module pin and the microstrip printed circuit board socket. In addition, since the installation gap between the microstrip printed circuit board socket and the low noise amplifier module pin is only 0.2mm 0.4mm, in order to avoid the abnormal plugging problem caused by the poor consistency of the plumb degree of the low noise amplifier module pin, a secondary identification and positioning function is added. The center point and angle of the pin are recognized by the first top vision CCD4, and then the position of the root of the pin is obtained according to the CAD data. The top vision CCD4 moves to the root position of the pin to take a picture to find the pixel position of the pin, and finally the offset of the top of the pin is obtained to achieve it.

[0034] After the assembly robot 1 completes the operation, the screw-mounting robot 2 carries the corresponding electric screwdriver to the designated position, and then picks up the screw from the countersunk screw feeder 8 or the combined screw feeding unit 7, and moves to the glue coating unit 11 for thread glue coating. Finally, the screw is screwed into the corresponding mounting hole according to the designated screw-mounting sequence, and torque is applied to lock it. When the product needs to be flipped, a flipping mechanism is designed and installed on both sides of the assembly unit. During operation, the clamps on both sides hold the product against the servo motor 3, which drives the clamps to complete the plane flipping of the product.

[0035] The robot intelligent assembly system uses OCR optical character recognition technology to complete the automatic classification and storage of assembly data reports and multimedia photos. Affected by factors such as the randomness of the placement of components and parts and color processing, it is necessary to first identify the rotation angle of the device and rotate the image, and then ensure that the text is rotated to the positive direction and the text is correctly segmented before recognizing and reorganizing to form the correct product logo. Finally, the recognized logo is used as a keyword, and other data of the current product is stored in the corresponding database or folder identified by this keyword, realizing the automatic storage of assembly data and multimedia photos.

[0036] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A robot intelligent assembly system, characterized in that: The system includes a first four-axis industrial robot, a second four-axis industrial robot, an assembly unit, a photographing unit, a gluing unit and a software control system; The assembly unit is located at the center of the assembly system, the first four-axis industrial robot and the second four-axis industrial robot are separated on both sides of the assembly unit, and the installation flange centers of the two robots are at the same distance from the center of the assembly unit. The assembly unit is used to cooperate with the first and second four-axis industrial robots to complete the mechanical assembly operations of various parts of the product according to the instructions of the software control system; The first four-axis industrial robot is an assembly robot, which is equipped with a first top vision CCD, an intelligent gripper and a component suction nozzle on its arm and can achieve a rotation within 270° in the circumferential direction, and is used to select a component picking method according to the instructions of the software control system. The first top vision CCD is combined with the bottom vision CCD to achieve precise alignment and installation of components using image acquisition, analysis and processing technology; the bottom vision CCD is located on the side of the assembly unit; The second four-axis industrial robot is a screw-mounting robot, which is equipped with a second top vision CCD and an intelligent electric screwdriver on its arm and can realize rotation within 270° in the circumferential direction. It is used to carry the corresponding intelligent electric screwdriver to the specified position to suck the screw according to the instruction of the software control system, and then move to the glue coating unit to apply thread glue. The second top vision CCD is combined with the bottom vision CCD to realize the alignment installation of the screw by using image acquisition, analysis and processing technology, and then apply torque to the screw to lock it according to the instruction of the software control system; The photographing unit is located at the lower side of the first four-axis industrial robot. When the first four-axis industrial robot picks up the product and places it on the rotating platform, the photographing unit takes multi-directional photographs of the product according to the instructions of the software control system and cooperates with the first top visual CCD of the first four-axis industrial robot to use OCR optical character recognition technology to complete automatic classification and storage of multimedia photos. The gluing unit is located below the assembly unit and includes two glue cylinders, each of which contains different glue liquids. When the second four-axis industrial robot picks up a screw of corresponding specification and moves to the top of the specified glue cylinder according to the instruction of the software control system, the quantitative application of thread glue is achieved by controlling the height of the screw penetrating into the glue needle. The software control system is used to provide instructions to the controllers in the first and second four-axis industrial robots and the intelligent electric screwdriver in the robot intelligent assembly system, so that the first and second four-axis industrial robots and the intelligent electric screwdriver can be driven to complete the picking and installation of parts, screw locking, abnormal state monitoring, alarm, and feedback operations; and cooperate with the first and second four-axis industrial robots and the camera unit to complete the automatic classification and storage of data reports and multimedia photos; The first and second four-axis industrial robots are respectively equipped with the first and second top vision CCDs to take photos, identify and locate the lower-level components and the top surfaces of the threaded holes to obtain the coordinates of the center points of the lower-level components and the threaded holes, and then select the reference points of the lower-level components according to the surface features of the lower-level components, and determine the placement angle of the lower-level components by calculating the angle and position coordinate offset of the coordinates of the center points of the lower-level components relative to the reference points of the lower-level components; the first and second four-axis industrial robots pick up the upper-level components and screws and move them to the top of the bottom vision CCD and obtain the coordinates of the center points of the components and the bottom surfaces of the screws with the help of the photos taken by them; the position corresponding to the reference point of the lower-level components when installed is selected from the bottom surface of the upper-level components as the reference point of the upper-level components, and the angle and position coordinate offset of the coordinates of the center points of the upper-level components relative to the reference points of the upper-level components are calculated to determine the placement angle of the upper-level components; the alignment of the screws and the threaded holes is achieved by aligning the coordinates of the center points of the screws and the threaded holes; The obtained data is calibrated with nine-point coordinates, and the current pixel coordinates are translated, rotated, and scaled to generate an affine matrix to realize the conversion of the pixel coordinate system to the relative position in the world coordinate system of the first and second four-axis industrial robots. Then, the hand-eye calibration is used to obtain the transformation relationship between the terminal coordinate system of the first and second four-axis industrial robots and the camera coordinate system, respectively, to realize the unique correspondence between the image coordinate system and the coordinates of the working points of the first and second four-axis industrial robots; The center point and angle of the antenna low noise amplifier module pin are identified through the first top vision CCD, and then the position of the root of the low noise amplifier module pin is obtained according to the CAD data. The first four-axis industrial robot equipped with the first top vision CCD moves to the root position of the low noise amplifier module pin to take a picture to find the pixel position of the low noise amplifier module pin, and the top offset of the low noise amplifier module pin is obtained by calculation. During assembly, this offset is added to the identified center point coordinate position to achieve the alignment installation of the low noise amplifier module pin and the microstrip printed circuit board socket.

2. The robot intelligent assembly system according to claim 1, characterized in that: When the first and second top vision CCD recognition coordinates are consistent with the bottom vision CCD recognition coordinates, the alignment and installation of parts and screws are directly completed; conversely, when the first and second top vision CCD recognition coordinates are inconsistent with the bottom vision CCD recognition coordinates, the difference in the angle and axial position of the two recognition coordinates is calculated, and the first and second four-axis industrial robots complete the angle and axial position adjustment to make the two recognition coordinates correspond to each other.

3. The robot intelligent assembly system according to claim 1, characterized in that: A cylindrical component placement platform is arranged at the center of the assembly unit, and the component placement platform is driven by a first servo motor to complete the lifting operation in the Z-axis direction; flipping mechanisms are arranged on both sides of the component placement platform for the component clamping and flipping operation.

4. The robot intelligent assembly system according to claim 1, characterized in that: The photographing unit includes a high-resolution color camera, a camera bracket and a rotating platform. Two high-resolution color cameras are respectively installed directly above the top of the camera bracket and at an angle of 45°, with the lenses facing the rotating platform. After the first four-axis industrial robot picks up the parts and places them on the rotating platform, the second servo motor drives the camera bracket to move to the rotating platform position to take pictures of the parts. The rotating platform is used to realize multi-directional photography within 360° in the Y-axis direction.

5. The robot intelligent assembly system according to claim 1, characterized in that: The glue coating unit is controlled by PLC, which receives software control system instructions and feedback information through I / O signal control or serial communication to control the glue dispensing needle to stably discharge glue. The glue coating cylinder is vertically fixed under the assembly unit by a fixed bracket, and the glue dispensing is achieved by controlling the up and down movement of the internal piston through air pressure.

6. The robot intelligent assembly system according to claim 1, characterized in that: The software control system is used to streamline the assembly steps through program compilation according to the process flow, output the product assembly process information and feedback in the form of reports, promptly alarm for abnormal conditions, establish communication with the intelligent electric batch controller, monitor the locking data of each screw, and intelligently judge the buckle failure.

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