A trimming end effector

Abstract

This invention relates to a trimming end effector. The device includes a trimming module, a vision inspection module, an expansion module, and electrical and pneumatic control modules. This device replaces existing manual trimming methods with automated equipment, improving efficiency and reducing operator injury. Compared to existing end effectors, this device can adapt to both offline and real-time online compensation, and can select appropriate algorithm strategies based on factors such as the characteristics of the workpiece. The same trimming end effector can be used to adapt to different product configurations, significantly improving product adaptability. The device features a detachable expansion module at the front end, enabling automatic tool changing, chip removal, and clamping functions. The trimming end effector achieves stable connection with a robot via a quick-change mechanism. The quick-change module allows for high-precision, repeatable connections, enabling different processing functions to be performed at the same workstation according to process requirements. This device has broad application prospects in the aircraft assembly industry.

Description

Technical Field

[0001] This invention belongs to the technical field of automated machining equipment, and particularly relates to a trimming end effector. Background Technology

[0002] In the field of aircraft assembly, the requirement for seam gaps in skin is generally less than 1mm. With the pursuit of stealth performance in fifth-generation aircraft, the requirement for seam gaps has been increased to 0.5mm or even higher.

[0003] In actual assembly, operators need to test assemble the material inside the frame, making it difficult to use ordinary CNC milling machines. Currently, manual trimming is the only option. The method for controlling the allowance through manual trimming is as follows: on the assembly frame, lines are drawn along the mating datum on the composite skin. Then, the composite skin is removed from the frame for rough trimming, then back on the frame to align with the datum, and the process is repeated multiple times to ensure a mating gap of approximately 1mm. Manual trimming is labor-intensive, time-consuming, and inefficient, consuming a significant amount of manpower. Furthermore, because the trimmed surfaces are mostly curved, current manual methods cannot meet the trimming precision requirements for the skin. With the widespread application of carbon fiber composite skins, manual trimming also generates a large amount of toxic dust, which can enter the human body through the respiratory system or skin contact. Long-term exposure to this work can cause irreversible and serious harm to workers' health.

[0004] For the reasons mentioned above, automated equipment (such as industrial robots) has been introduced to replace manual operation in various mechanical processing fields. As a result, there is an urgent need for various end-processing equipment that can be used in combination with automated equipment. Summary of the Invention

[0005] To overcome the aforementioned drawbacks of manual trimming operations, this invention proposes a novel trimming end effector that can be mounted on an industrial robot.

[0006] During our research and development, we recognized that automated and intelligent trimming of the inner skin is a definite development trend in order to ensure the quality of skin seam trimming, improve efficiency, and meet the design and manufacturing standards of next-generation aircraft. Considering the large size and complex shape of the skin, and from the perspective of system flexibility, we adopted a six-axis serial industrial robot as the carrier and a trimming end effector as the tool to achieve flexible trimming processing of skins of different specifications. Because the positions and working conditions of the skin to be trimmed vary, the end effector must not only meet the basic trimming functions but also ensure that the vision inspection module can automatically adjust its position and accurately identify patterns under various working conditions to meet different trimming requirements.

[0007] This invention provides a trimming end effector, which includes: a trimming module 3, a vision inspection module 2, an expansion module 4, and an electronic control and pneumatic control module;

[0008] The trimming end effector is mounted on the robot via quick-change module 1, and the connection structure is reliable and stable.

[0009] Furthermore, the trimming end effector of this invention follows the design principles of lightweight, high integration, and modularity, employing a fixed spindle; the vision inspection module is configured with one or more degrees of freedom to adapt to different references; the expansion module provides automatic tool changing, chip suction, clamping functions, and customizable layout options; wires, cables, and pipes are all concealed, and cable carriers and other bundled installation measures are used along the robot body's wiring path to adapt to various changes during equipment operation, preventing wire pulling during operation; the quick-change module allows for high-precision repeated connections, and the entire system can complete different types of processing operations at the same workstation according to process requirements.

[0010] Furthermore, the trimming module 3 in the trimming end effector of the present invention includes an electric spindle 301, a tool clamping device 302 (i.e., a tool holder), a tool 303, and a spindle fixing frame 304, wherein:

[0011] The electric spindle provides power for the tool rotation and features a compact structure, light weight, low inertia, low noise, and fast response. It also boasts high speed and power, facilitating spindle positioning. The spindle speed is controlled by a spindle motor, while the temperature rise within the spindle unit is limited by a cooling system. Speed ​​and angular displacement sensors are mounted at the rear end of the spindle, while the inner tapered hole and end face at the front end are used to mount the tool holder 302 and the tool 303. The electric spindle bearings utilize high-speed bearing technology, offering wear resistance, heat resistance, and a long service life. The electric spindle has a closed structure, preventing internal oil spillage and dripping, making it suitable for machining aluminum alloys, titanium alloys, and composite materials.

[0012] The tool holder uses the HSK tool system, which is a high-speed short conical tool holder. The interface adopts a method of simultaneous positioning of the conical surface and the end face. The tool holder is hollow, the cone length is short, and the taper is 1 / 10, which is conducive to achieving lightweight and high-speed tool changes. Due to the use of hollow cone and end face positioning, the radial deformation difference between the spindle hole and the tool holder during high-speed machining is compensated, and the axial positioning error is completely eliminated, making high-speed and high-precision machining possible.

[0013] The cutting tool is a solid carbide multi-flute micro-tooth end mill, and each tool has a unique identifier for easy identification and reading, thereby enabling tool management.

[0014] This invention employs a multi-tooth micro-end mill, which can simultaneously achieve the machining effects of both left-hand and right-hand helical cutting edges. On one hand, the left-hand micro-tooth offsets the upward lifting force F exerted by the cutter on the workpiece. r Simultaneously, it can shear burrs on the upper surface; on the other hand, the right-hand micro-tooth counteracts the downward pressure F exerted by the tool on the workpiece. lSimultaneously, it can shear burrs on the lower surface, and the combined effect of these two factors balances the Z-axis cutting force on the workpiece to a certain extent. A reasonable tooth arrangement allows the micro-tooth end mill to effectively suppress surface damage when milling workpieces at any axial position. Therefore, the structure of the micro-tooth end mill can effectively suppress burr damage on both the upper and lower surfaces of the workpiece, while achieving a low surface roughness Sa while meeting quality requirements, making it the preferred tool structure for CFRP milling.

[0015] Furthermore, the tool clamping device in the trimming end effector of the present invention is equipped with a forward movement balance adjustment to ensure the dynamic balance of the tool holder;

[0016] The tool clamping device is embedded with an RFID chip as a storage carrier for tool information to achieve tool management.

[0017] Furthermore, the vision detection module 2 in the trimming end effector of the present invention is used to identify the processing reference and calculate the compensation amount for the processing reference error caused by clamping, so as to ensure the positional accuracy of trimming; the vision detection module includes an image acquisition unit and detection and recognition software; wherein:

[0018] The image acquisition unit is used to capture and acquire images of the processing reference according to process requirements. The image acquisition unit includes a 3D contour scanner 201 and a motion mechanism. The 3D contour scanner uses the laser triangulation principle for measurement. Specifically, through a lens group, the laser beam is magnified to form a static laser line projected onto the surface of the object being measured. The laser line forms diffuse reflection on the surface of the object, and the reflected light passes through a high-quality optical system and is projected onto a sensitive photosensitive matrix. In addition to the distance information (Z-axis) from the sensor to the surface being measured, the controller can also calculate the position information (X-axis) along the laser line using the image information. Within a two-dimensional coordinate system centered on the sensor, the contour scanner measures and outputs a set of two-dimensional coordinate values. By moving the object being measured or the contour scanner probe, a set of three-dimensional measurement values ​​can be obtained.

[0019] The motion mechanism consists of a scanner bracket 202, a connecting plate 203, a miniature electric turntable 204, a slide table 205, and a guide rail 206. The motion mechanism is adaptable to both offline compensation and online real-time compensation processing modes, and can be adapted to different structural products using the same trimming end effector, effectively improving product adaptability.

[0020] The image acquisition unit works as follows: the detection and recognition software controls the 3D contour scanner 201 to acquire images, the host computer performs image preprocessing, reference recognition, and deviation calculation, and sends the reference position deviation value to the robot to complete the processing reference alignment and trimming end effector pose adjustment. Since the skin to be trimmed has different positions and working conditions, the vision inspection module 2 needs to be able to automatically adjust its position and accurately identify the graphics. Therefore, the vision inspection module 2 is equipped with a device that can translate and rotate. The 3D contour scanner 201 is fixed to the scanner bracket 202, and the scanner bracket 202 is connected to the micro electric turntable 204 and the slide table 205 via the connecting plate 203. The slide table 205 is mounted on the guide rail 206. The guide rail 206 is driven by a servo motor to rotate the lead screw, thereby moving the slide table 205 on the guide rail 206. Since the slide table 205 is connected to the connecting plate 203, it drives the 3D contour scanner 201 to complete the translational movement. The miniature electric turntable 204 consists of a servo motor, a worm gear, and bearings. When the 3D contour scanner 201 needs to be rotated, the miniature electric turntable 204 is connected to the scanner bracket 202. The servo motor drives the worm gear to rotate the scanner bracket 202, thereby driving the 3D contour scanner 201 to rotate.

[0021] Furthermore, the image acquisition unit in the trimming end effector of the present invention is adapted to the following two compensation methods:

[0022] (1) Offline compensation: Before trimming, the processing reference is detected by the visual reference detection module, and the trajectory and pose of the robot are compensated according to the processing reference before trimming.

[0023] (2) Online real-time compensation: During the trimming process, the visual reference detection module measures the features of the workpiece in real time, calculates the trajectory pose compensation value and performs robot pose compensation.

[0024] The image acquisition unit is divided into two layout methods: reference front and reference rear.

[0025] Reference front position: The trimming reference is located in front of the edge to be trimmed relative to the trimming end effector. For the reference front position working condition, the relative position of the reference and the workpiece to be processed is different. In order to use the same trimming end effector in the online real-time compensation mode to meet the processing requirements under different working conditions, the image acquisition unit is configured with two degrees of freedom, one translation and one rotation, to adapt to the two processing modes of offline compensation and online real-time compensation.

[0026] Rear reference: Relative to the trimming end effector, the trimming reference is located behind the edge to be trimmed; for the rear reference working condition, it is necessary to ensure that the tool end face is tangent to the reference and the edge to be trimmed. Therefore, the spindle is parallel to the reference plane, and the reference position and attitude are fixed relative to the tool. At this time, the image acquisition unit is only configured with one translational degree of freedom.

[0027] Furthermore, the translational degree of freedom in the trimming end effector of the present invention is implemented as follows:

[0028] The translational motion precession mechanism uses a servo motor to drive the lead screw to rotate, which in turn drives the slide to move on the guide rail. Its drive mechanism is a fully enclosed actuator, which is equipped with an inner slider. The LM slider and the ball screw nut of this inner slider are integrally constructed on the inner side of the high-rigidity U-shaped cross-section outer track. Its main advantages are: equal load in four directions, high precision, and high rigidity. The translational degree of freedom accuracy is measured by a linear grating ruler and corrected by the control system circuit. There are no mechanical transmission parts during the measurement of the linear axis position by the linear grating ruler. The mechanical motion error of the slider is detected by the linear grating ruler in the slide and corrected by the control system circuit. Therefore, the application of the grating ruler can eliminate multiple potential error sources, including: reverse error; and motion characteristic error caused by ball screw pitch error.

[0029] The rotational degree of freedom is implemented as follows:

[0030] The rotational motion drive mechanism is a miniature electric turntable equipped with a servo motor. The miniature electric turntable adopts a worm gear transmission mode and uses a high-precision shaft system inside, which has high rotational accuracy, strong load-bearing capacity, and smooth movement. The rotational freedom is realized under the rotational drive of the miniature electric turntable.

[0031] Furthermore, to adapt to different product needs, the trimming end effector of the present invention is equipped with a detachable expansion module at the front end. The expansion module is used to realize automatic tool changing, chip suction, and clamping functions; it can also be integrated to provide a rapid response solution for different working conditions in the future.

[0032] The drive system of the expansion module uses two independent cylinders, which are respectively fixed to the main body adapter plate of the trimming end effector;

[0033] The expansion module includes a chip suction module and an independent clamping module; wherein:

[0034] The chip suction module is equipped with a detachable flexible flared chip suction port at the front end, which can achieve 360° surround of the tool. The front end of the chip suction module is made of flexible material, which can make the chip suction port fit the product surface to the maximum extent without damaging the product surface, providing good suction. The flared design makes the chip suction port turn outward, thereby avoiding the chip getting into the tool during the trimming process and affecting the processing.

[0035] In the working state, the cylinder pushes the push rod to extend the expansion module, and the chip suction port surrounds the tool and contacts the product to be trimmed. The chip suction port continuously moves with the tool during the trimming process. Therefore, regardless of the relative position of the edge to be trimmed and the trimming end actuator, it can provide the same effective suction force. In the non-working state, the cylinder push rod retracts, driving the chip suction module to retract. At this time, the chip suction module does not occupy the front end space. This state is also applicable to working conditions where there is interference around the cutting edge.

[0036] The chip suction module is equipped with an automatic opening and closing mechanism at the front end. When a tool change is required, the cylinder push rod continues to retract, driving the opening and closing mechanism to open, so that the chip suction module separates from the middle, thereby avoiding the tool change path and realizing the automatic tool change function.

[0037] The independent clamping module is equipped with two clamping heads, each controlled independently by two cylinders. Each head has two sets of plungers to ensure that the surface to be repaired is in close contact with the back support during processing. When the independent clamping module is working, the chip suction port is fixed on the spindle base and guided to the chip discharge position by a universal tube. This structure is suitable for working conditions where the surface to be repaired has poor rigidity, has an effective support structure on its back, and the surface to be repaired is not in good contact with the back support.

[0038] Furthermore, the extended module in the trimming end effector of the present invention includes an integrated chip suction and pressing module. The integrated chip suction and pressing module combines chip suction and pressing functions. Using the full circumference pressing end, while pressing the surface to be trimmed, the chip suction port is sent to the edge to be trimmed.

[0039] The integrated chip suction and clamping module is equipped with an automatic opening and closing mechanism at the front end. When a tool change is required, the cylinder push rod continues to retract, driving the opening and closing mechanism to open, so that the integrated chip suction and clamping module separates from the middle, thereby avoiding the tool change path and realizing the automatic tool change function.

[0040] Furthermore, the trimming end effector of the present invention is equipped with one electric spindle, two motors, two cylinders and one grating ruler. Based on this design and with a margin reserved, the electric control and pneumatic control modules are configured.

[0041] Furthermore, the present invention also relates to the application of the above-mentioned trimming end effector in the aircraft assembly industry.

[0042] In summary, the trimming end effector of the present invention has the following advantages:

[0043] (1) Replacing the existing manual trimming method with automated equipment can improve quality and efficiency and reduce physical harm to operators.

[0044] (2) Compared with other types of existing automated processing end effectors, the device of the present invention can adapt to offline compensation and online real-time compensation, and can select a suitable algorithm strategy based on comprehensive factors such as the characteristics of the workpiece itself.

[0045] (3) Compared with other types of existing automated processing end effectors, the present invention can adapt to different product configurations using the same trimming end effector, and the product adaptability is greatly improved.

[0046] (4) The front end of this trimming end effector is equipped with a detachable expansion module, which can provide different functions such as chip suction and clamping according to customer needs, while realizing the automatic tool changing function. It can also be integrated to provide a quick response solution for different working conditions in the future.

[0047] (5) This trimming end effector achieves a stable connection with the robot through a quick-change mechanism. The quick-change module can achieve high-precision repeated connection and can provide the possibility of achieving different processing functions at the same workstation according to process requirements. Attached Figure Description

[0048] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments of the present invention will be briefly introduced below. Obviously, the following drawings 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.

[0049] Figure 1 This is a schematic diagram of the basic structure of the trimming end effector of the present invention.

[0050] Figure 2 This is a schematic diagram illustrating the installation method of the trimming end effector and robot of the present invention.

[0051] Figure 3 This is a schematic diagram of the trimming module in the trimming end effector of the present invention.

[0052] Figure 4 This is a schematic diagram of the milling force state in the trimming end effector of the present invention.

[0053] Figure 5 This is a schematic diagram of the laser triangular reflection principle in the trimming end effector of the present invention.

[0054] Figure 6 This is a schematic diagram illustrating the working condition of ensuring the seam gap after trimming one or both sides of adjacent skin in an embodiment of the trimming end actuator of the present invention.

[0055] Figure 7 This is a schematic diagram illustrating the working condition of ensuring the seam gap between the skin and the skeleton after the skin is trimmed in an embodiment of the trimming end effector of the present invention.

[0056] Figure 8 This is a schematic diagram illustrating the relative pose of the skin and the reference after trimming in an embodiment of the trimming end effector of the present invention.

[0057] Figure 9 This is a schematic diagram of the degree-of-freedom configuration of the image acquisition unit in the visual inspection module of the trimming end effector of the present invention.

[0058] Figure 10 This is a schematic diagram of the actuator structure in the trimming end effector of the present invention.

[0059] Figure 11 This is a schematic diagram of the miniature electric turntable in the trimming end effector of the present invention.

[0060] Figure 12 This is a schematic diagram illustrating the working condition of ensuring that the skin is flush with the underlying skeleton after trimming in an embodiment of the trimming end effector of the present invention.

[0061] Figure 13 This is a schematic diagram showing the position of the extension module driving cylinder in the trimming end effector of the present invention.

[0062] Figure 14 This is a schematic diagram of the chip suction module in the working state of the trimming end effector of the present invention.

[0063] Figure 15 This is a schematic diagram of the chip suction module in the non-working state of the trimming end effector of the present invention.

[0064] Figure 16 This is a schematic diagram of the chip suction module in the tool changing state of the trimming end effector of the present invention.

[0065] Figure 17 This is a schematic diagram of the independent clamping module in the trimming end effector of the present invention.

[0066] Figure 18 This is a schematic diagram of the integrated chip suction and clamping module in the trimming end effector of the present invention.

[0067] Figure 19 This is a schematic diagram of the electrical and pneumatic control modules in the trimming end effector of the present invention.

[0068] Figure captions: 1. Quick-change module; 2. Visual inspection module; 3. Trimming module; 4. Expansion module; 201. 3D contour scanner; 202. Scanner bracket; 203. Connecting plate; 204. Miniature electric turntable; 205. Slide table; 206. Guide rail; 301. Electric spindle; 302. Tool clamping device; 303. Tool; 304. Spindle fixing bracket. Detailed Implementation

[0069] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. This invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this invention.

[0070] At the same time, it should be understood that the scope of protection of the present invention is not limited to the specific embodiments described below; it should also be understood that the terminology used in the embodiments of the present invention is for describing specific embodiments and not for limiting the scope of protection of the present invention.

[0071] Example: A trimming end effector

[0072] The trimming end effector of the present invention mainly includes a trimming module 3, a vision inspection module 2, an expansion module 4, and an electrical control and pneumatic control module. It is installed on the robot through a quick-change module 1, and the connection structure is reliable and stable.

[0073] This trimming end effector is designed in accordance with the principles of lightweight, high integration and modularity. It adopts a fixed spindle, and the vision inspection module has a degree of freedom in configuration to adapt to different references. The expansion module provides optional functions such as chip suction and clamping. Its wires, cables and pipes are arranged in a concealed manner to adapt to various changes in the equipment operation process, and there will be no wire pulling or other phenomena during the operation of the equipment.

[0074] This trimming end effector connects to the robot via a quick-change module, and its basic structure is as follows: Figure 1 As shown, its installation method is as follows Figure 2 As shown. The quick-change module enables high-precision repeatable connections, and the entire system can complete different types of processing operations at the same workstation according to process requirements.

[0075] (I) Trimming Module

[0076] The trimming module includes an electric spindle 301, a tool holder 302 (i.e., a tool holder), a tool 303, and a spindle mounting bracket 304 (i.e., a mounting structure), etc. Figure 3 As shown, it uses an electric spindle to drive the tool to rotate, thus achieving the trimming function.

[0077] 1.1 Electric Spindle

[0078] Electric spindles provide power for tool rotation and offer advantages such as compact structure, light weight, low inertia, low noise, and fast response. They also boast high speed, high power, and easy spindle positioning. The electric spindle bearings utilize high-speed bearing technology, are wear-resistant and heat-resistant, and have a lifespan several times that of traditional bearings.

[0079] The spindle speed is controlled by the spindle motor, while the temperature rise within the spindle unit is limited by the cooling system. Speed ​​and angular displacement sensors are installed at the rear end of the spindle, and the inner tapered hole and end face at the front end are used to mount the tool holder 302 and the cutting tool 303.

[0080] The electric spindle of this application adopts a closed structure, so that the internal oil will not overflow or drip, and it is suitable for machining aluminum alloys, titanium alloys and composite materials.

[0081] 1.2 Tool clamping device

[0082] The tool holder uses the HSK tool system, a new type of high-speed short conical tool holder. The interface employs simultaneous positioning via the conical surface and end face. The tool holder is hollow, with a short cone length and a taper of 1 / 10, which facilitates lightweight and high-speed tool changes. The use of a hollow cone and end face positioning compensates for the radial deformation difference between the spindle bore and the tool holder during high-speed machining and completely eliminates axial positioning errors, making high-speed, high-precision machining possible.

[0083] The tool holder is embedded with a Balluff RFID chip (BIS C-122-04 / L) as a storage medium for tool information to enable tool management.

[0084] The tool holder is factory-balanced to ensure dynamic balance.

[0085] 1.3 Cutting tools

[0086] We use solid carbide micro-tooth end mills, each with a unique identifier for easy identification and reading, thus enabling tool management.

[0087] For straight-blade end mills, when the vibration amplitude in the workpiece thickness direction is too large, the peeling effect of the cutting edge on the surface fibers is stronger than steady-state cutting. Because the upper and lower surfaces of the workpiece are in a weakly constrained state, burrs or tearing damage are easily caused on both the upper and lower surfaces. Figure 4 As shown, under vibration, on the one hand, when the milling end of the workpiece is subjected to the action of the tool F lo When the workpiece is below the horizontal plane of the clamping end, the motion state of the tool can be equivalent to the machining effect of a left-hand spiral end mill. This is because the workpiece is subjected to a force F in the negative Z-axis direction of the left-hand spiral end mill. l This leads to burrs easily appearing on the lower surface layer; on the other hand, when the milled end of the workpiece is subjected to the action of the tool, F up When the workpiece is above the horizontal plane of the clamping end, the motion state of the tool can be equivalent to the machining effect of a right-hand spiral end mill. This is because the workpiece is subjected to a force F in the positive Z-axis direction of the right-hand spiral end mill. rThis leads to burrs easily appearing on the upper surface. For multi-tooth micro-end mills, the machining effect of both left and right helical cutting edges can be taken into account simultaneously. On the one hand, the left helical micro-tooth offsets the upward lifting force F of the tool on the workpiece. r Simultaneously, it can shear burrs on the upper surface; on the other hand, the right-hand micro-tooth counteracts the downward pressure F exerted by the tool on the workpiece. l Simultaneously, it can shear burrs on the lower surface, and the combined effect of these two factors balances the Z-axis cutting force on the workpiece to a certain extent. A reasonable tooth arrangement allows the micro-tooth end mill to effectively suppress surface damage when milling workpieces at any axial position. Therefore, the structure of the micro-tooth end mill can effectively suppress burr damage on both the upper and lower surfaces of the workpiece, while achieving a low surface roughness Sa while meeting quality requirements, making it the preferred tool structure for CFRP milling.

[0088] (II) Visual Inspection Module

[0089] The vision inspection module is used to identify the machining datum and calculate the compensation amount for machining datum errors caused by clamping, ensuring the positional accuracy of trimming. It mainly includes an image acquisition unit and detection and recognition software.

[0090] 2.1 Image Acquisition Unit

[0091] (1) 3D contour scanner

[0092] The image acquisition unit, primarily composed of a 3D contour scanner, is used to capture and acquire images of the processing reference according to process requirements. The 3D contour scanner employs the principle of laser triangulation, such as... Figure 5 As shown, a laser beam is magnified into a static laser line and projected onto the surface of the object being measured through a special lens group. The laser line causes diffuse reflection on the surface of the object, and the reflected light passes through a high-quality optical system and is projected onto a sensitive photosensitive matrix. In addition to the distance information from the sensor to the surface being measured (Z-axis), the controller can also calculate the position information along the laser line (X-axis) using image information. Within a two-dimensional coordinate system centered on the sensor, the profilometer measures and outputs a set of two-dimensional coordinate values. By moving the object being measured or the profilometer probe, a set of three-dimensional measurement values ​​can be obtained.

[0093] (2) Movement mechanism

[0094] This trimming end effector is compatible with two compensation technologies: offline compensation and online real-time compensation. Offline compensation refers to using a vision reference detection module to detect the machining reference before trimming, compensating for the robot's trajectory and pose before proceeding with the trimming process. Online real-time compensation refers to using a vision reference detection module to measure the workpiece's features in real time during the trimming process, calculating and compensating for the robot's pose.

[0095] The motion mechanism consists of a scanner bracket 202, a connecting plate 203, a miniature electric turntable 204, a slide table 205, and a guide rail 206. This motion mechanism is adaptable to both offline compensation and online real-time compensation processing modes, and can be adapted to different structural products using the same trimming end effector, effectively improving product adaptability.

[0096] The image acquisition unit works as follows: the detection and recognition software controls the 3D contour scanner 201 to acquire images. The host computer performs image preprocessing, reference recognition, and deviation calculation, and sends the reference position deviation value to the robot to complete the machining reference alignment and trimming end effector pose adjustment. Because the skin to be trimmed has different positions and working conditions, the vision inspection module 2 needs to be able to automatically adjust its position and accurately identify the graphics. Therefore, the vision inspection module 2 is equipped with a device that can translate and rotate. The 3D contour scanner 201 is fixed to the scanner bracket 202. The scanner bracket 202 is connected to the miniature electric turntable 204 and the slide table 205 via the connecting plate 203. The slide table 205 is mounted on the guide rail 206. The guide rail 206 is driven by a servo motor to rotate the lead screw, thereby moving the slide table 205 on the guide rail 206. Since the slide table 205 is connected to the connecting plate 203, it drives the 3D contour scanner 201 to complete the translational movement. The miniature electric turntable 204 consists of a servo motor, a worm gear, and bearings. When the 3D contour scanner 201 needs to be rotated, the miniature electric turntable 204 is connected to the scanner bracket 202. The servo motor drives the worm gear to rotate the scanner bracket 202, thereby driving the 3D contour scanner 201 to rotate.

[0097] Based on the layout of the reference front and reference back, image acquisition units can be divided into two main categories:

[0098] a) Reference in front, that is: relative to the trimming end effector, the trimming reference is located in front of the edge to be trimmed, corresponding to the following three working conditions (this is just an example and can be adapted to more working conditions):

[0099] Working Condition 1: Ensure the seam gap after trimming one or both sides of adjacent skins. Example working condition is as follows: Figure 6 As shown.

[0100] Working Condition 2: After trimming the skin, ensure the seam gap between it and the frame. Example working condition is as follows: Figure 7 As shown.

[0101] Working condition 3: Using a certain feature as a reference, after trimming, ensure the relative pose (e.g., parallelism) of the skin and the reference. Example working condition is as follows: Figure 8 As shown.

[0102] For pre-work conditions where the reference and the workpiece are at different relative positions, the image acquisition unit is configured with one translational and one rotational degree of freedom to meet the processing requirements under different conditions using the same trimming end effector in online real-time compensation mode. The basic structure includes guide rails, slides, servo motors, and adapter fixtures, etc. Figure 9 As shown. Its advantage lies in its adaptability to both offline compensation and online real-time compensation processing modes, and it can be adapted to different structural products through the same trimming end effector, effectively improving product adaptability.

[0103] The translational motion precession mechanism employs a servo motor to drive a lead screw, which in turn moves the slide table along the guide rail. The drive mechanism uses a compact, high-rigidity, high-precision, fully enclosed actuator, the structure of which is as follows: Figure 10 As shown.

[0104] This series of actuators is equipped with an internal slider, in which the LM slider and ball screw nut are integrally constructed on the inner side of the high-rigidity U-shaped cross-section outer track. Its main advantages are: four-way equal load, high precision, and high rigidity.

[0105] The accuracy of translational degrees of freedom is guaranteed by the linear grating ruler. There are no mechanical transmission parts during the measurement of the linear axis position by the linear grating ruler. The mechanical motion error of the slider is detected by the linear grating ruler in the slide plate and corrected by the control system circuit. Therefore, the application of the grating ruler can eliminate multiple potential error sources, including: reverse error; and motion characteristic error caused by ball screw pitch error.

[0106] The rotary motion drive mechanism uses a miniature electric turntable equipped with a servo motor, such as... Figure 11 As shown, this electric rotary table adopts a worm gear transmission mode and undergoes special processing, resulting in high wear resistance, reliable precision, and a high-precision internal shaft system, ensuring high rotational accuracy, strong load-bearing capacity, and smooth movement.

[0107] b) Rear-mounted reference: The trimming reference is located behind the edge to be trimmed relative to the trimming end effector. This corresponds to the condition where the skin trimming ensures flush alignment with the underlying skeleton. Figure 12 As shown:

[0108] In this type of working condition, it is necessary to ensure that the tool end face is tangent to the reference and the edge to be repaired. Therefore, the spindle is parallel to the reference plane, and the reference position and posture are fixed relative to the tool, providing only one translational degree of freedom for the vision inspection module.

[0109] 2.2 Detection and Recognition Software

[0110] The detection and recognition software controls the 3D contour scanner to complete image acquisition. The host computer performs image preprocessing, benchmark recognition, and deviation calculation, and sends the benchmark position deviation value to the robot to complete the machining benchmark alignment and trimming end effector pose adjustment.

[0111] (III) Extended Modules

[0112] To adapt to different product needs, the trimming end effector is equipped with a detachable expansion module at the front end. While achieving automatic tool changing, it can provide different functions such as chip suction and clamping according to customer needs. It can also be integrated to provide a quick response solution for different working conditions in the future.

[0113] The expansion module drive system uses two independent cylinders, each fixed to the adapter plate of the trimming end effector body, such as... Figure 13 As shown.

[0114] (1) Dust collection module

[0115] The chip suction module is a general-purpose module with a flexible, flared chip suction port at the front. In operation, a cylinder pushes a push rod to extend the module, allowing the flexible chip suction port to completely surround the tool and contact the product to be trimmed. Figure 14 As shown. Its main advantages are:

[0116] a) It achieves 360° surround of the tool and can continuously follow the tool during the trimming process. Therefore, it can provide the same effective suction force regardless of the relative position of the edge to be trimmed and the trimming end actuator.

[0117] b) The front end is made of flexible material, which allows the dust suction port to fit the product surface to the maximum extent without damaging the product surface, providing good suction;

[0118] c) The flared design makes the chip suction port turn outward, thus preventing the chip from getting caught in the tool during the trimming process and affecting the machining.

[0119] d) The flexible chip suction port and the main body of the expansion module are designed separately, which makes them easy to install, remove and maintain.

[0120] When not in operation, the cylinder push rod retracts, causing the chip suction module to retract as follows: Figure 15 As shown, in this state, the chip suction module does not occupy the front-end space, and this state is also applicable to working conditions where there is interference around the cutting edge area.

[0121] Because the spindle has no degrees of freedom of movement, an automatic opening and closing mechanism is configured at the front end of the chip suction module to achieve automatic tool changing, such as... Figure 16 As shown, when a tool change is required, the cylinder push rod continues to retract, driving the opening and closing mechanism to open, causing the chip suction module to separate from the middle, thereby avoiding the tool change path.

[0122] (2) Independent clamping module

[0123] The independent clamping module is equipped with two clamping heads, each independently controlled by a cylinder, and each has two sets of plungers to ensure that the surface to be repaired is in close contact with the back support during processing. The independent clamping module is as follows: Figure 17 As shown, when using this expansion module, the chip suction port is fixed on the spindle base, and a universal joint is used to guide the chip suction port to the chip discharge position. This structure is suitable for working conditions where the surface to be repaired has poor rigidity, its back has an effective support structure, and the surface to be repaired does not fit well with the back support.

[0124] (3) Integrated chip suction and pressing module

[0125] The integrated chip suction and clamping module combines chip suction and clamping functions. Utilizing the full-circumference clamping end, it clamps the product while simultaneously delivering the chip suction port to the edge to be repaired. It also employs the same method as the chip suction module to achieve automatic tool changing. Its structure is as follows: Figure 18 As shown.

[0126] (iv) Electrical and pneumatic control modules

[0127] The intelligent trimming end effector consists of one electric spindle, two motors, two cylinders, and one linear encoder. Based on this design and with allowances for future expansion, it is equipped with electronic and pneumatic control modules, such as... Figure 19 As shown.

[0128] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to obtain equivalent embodiments without departing from the scope of the technical solution of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the technical solution of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A trimming end effector, characterized in that, The trimming end effector includes: a trimming module, a vision inspection module, an expansion module, and an electronic and pneumatic control module; The trimming end effector is mounted on the robot via a quick-change module; The trimming end effector is fixed to the spindle; the expansion module provides automatic tool changing, chip suction, and clamping functions; wires, cables, and pipes are all laid out in a concealed manner; The visual inspection module is used to identify the machining datum and calculate the compensation amount for machining datum errors caused by clamping, ensuring the positional accuracy of trimming; the visual inspection module includes an image acquisition unit and detection and recognition software; wherein: The image acquisition unit is used to capture and acquire images of the processing reference according to process requirements. The image acquisition unit includes a 3D contour scanner and a motion mechanism. The 3D contour scanner uses the laser triangular reflection principle for measurement. The motion mechanism includes a scanner bracket, a connecting plate, a miniature electric turntable, a slide, and a guide rail. The working process of the motion mechanism includes: fixing the 3D contour scanner to the scanner bracket, connecting the scanner bracket to the miniature electric turntable and the slide through the connecting plate, and installing the slide on the guide rail; the guide rail is driven by a servo motor to rotate the lead screw, thereby driving the slide to move on the guide rail. Since the slide is connected to the connecting plate, it drives the 3D contour scanner to complete the translational movement. The miniature electric turntable consists of a servo motor, a worm gear, and bearings. When it is necessary to rotate the 3D contour scanner, the miniature electric turntable is connected to the scanner bracket, and the servo motor drives the worm gear to rotate the scanner bracket, thereby driving the 3D contour scanner to rotate. The image acquisition unit is compatible with the following two compensation methods: (1) Offline compensation: Before trimming, the processing reference is detected by the visual reference detection module, and the trajectory and pose of the robot are compensated according to the processing reference before trimming. (2) Online real-time compensation: During the trimming process, the visual reference detection module measures the features of the workpiece in real time, calculates the trajectory pose compensation value and performs robot pose compensation; The image acquisition unit is divided into two layout methods: reference front and reference rear. Reference in front: The trimming reference is located in front of the edge to be trimmed relative to the trimming end effector; for reference in front working condition, the image acquisition unit is configured with two degrees of freedom, one translation and one rotation, to adapt to two processing modes: offline compensation and online real-time compensation. Rear reference: Relative to the trimming end effector, the trimming reference is located behind the edge to be trimmed; For the rear reference working condition, it is necessary to ensure that the tool end face is tangent to the reference and the edge to be trimmed. Therefore, the spindle is parallel to the reference plane, and the reference position and attitude are fixed relative to the tool. At this time, the image acquisition unit is only configured with one translational degree of freedom. The detection and recognition software controls the 3D contour scanner to complete image acquisition. The host computer performs image preprocessing, benchmark recognition, and deviation calculation, and sends the benchmark position deviation value to the robot to complete the machining benchmark alignment and trimming end effector pose adjustment.

2. The trimming end effector according to claim 1, characterized in that, The trimming module includes an electric spindle, a tool clamping device, and a tool, wherein: The electric spindle provides power for the rotation of the tool, and the electric spindle has a closed structure; The tool clamping device is a high-speed short conical tool holder. The interface adopts a method of simultaneous positioning of the conical surface and the end face. The tool holder is hollow and the taper is 1 / 10. The cutting tool is an alloy multi-tooth micro-end mill.

3. The trimming end effector according to claim 2, characterized in that, The tool clamping device is equipped with a forward movement balance adjustment to ensure the dynamic balance of the tool holder; The tool clamping device has an embedded chip that serves as a storage carrier for tool information, enabling tool management.

4. The trimming end effector according to claim 1, characterized in that, The translational degrees of freedom are implemented as follows: The translational motion precession mechanism uses a servo motor to drive the lead screw to rotate, which in turn drives the slide to move on the guide rail; its drive mechanism is a fully enclosed actuator; the accuracy of the translational degree of freedom is measured by a linear grating ruler and corrected by the control system circuit; The rotational degree of freedom is implemented as follows: The rotational motion drive mechanism is a miniature electric turntable equipped with a servo motor. The miniature electric turntable adopts a worm gear transmission mode, and the rotational freedom is achieved under the rotational drive of the miniature electric turntable.

5. The trimming end effector according to claim 1, characterized in that, The trimming end effector is equipped with a detachable expansion module at its front end, which is used to realize automatic tool changing, chip suction and clamping functions. The drive system of the expansion module uses two independent cylinders, which are respectively fixed to the main body adapter plate of the trimming end effector; The expansion module includes a chip suction module and an independent clamping module; wherein: The chip suction module is equipped with a detachable flexible flared chip suction port at the front end, which can achieve 360° surround of the tool. In the working state, the cylinder pushes the push rod to push out the extension module, and the chip suction port surrounds the tool all around and contacts the product to be trimmed. The chip suction port continuously moves with the tool during the trimming process. In the non-working state, the cylinder push rod retracts, which drives the chip suction module to retract. At this time, the chip suction module does not occupy the front end space. The chip suction module is equipped with an automatic opening and closing mechanism at the front end. When a tool change is required, the cylinder push rod continues to retract, driving the opening and closing mechanism to open, so that the chip suction module separates from the middle, thereby avoiding the tool change path and realizing the automatic tool change function. The independent clamping module is equipped with two clamping heads, each controlled independently by two cylinders. It is equipped with two sets of plungers to keep the surface to be repaired in close contact with the back support during the processing. When the independent clamping module is working, the chip suction port is fixed on the spindle base and a universal tube is used to guide the chip suction port to the chip discharge position.

6. The trimming end effector according to claim 1, characterized in that, The expansion module includes an integrated chip suction and pressing module, which combines chip suction and pressing functions. Using the full-circumference pressing end, the chip suction port is sent to the edge to be repaired while pressing the surface to be repaired. The integrated chip suction and clamping module is equipped with an automatic opening and closing mechanism at the front end. When a tool change is required, the cylinder push rod continues to retract, driving the opening and closing mechanism to open, so that the integrated chip suction and clamping module separates from the middle, thereby avoiding the tool change path and realizing the automatic tool change function.

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