An on-line robot assembly and composite machining device for difficult-to-machine materials

Abstract

The present application relates to a kind of robot online composite machining device of difficult-to-machine material, for the hole making, cutting work of ceramic matrix composite / high-temperature alloy and other materials of aircraft assembly, belong to the field of aviation manufacturing engineering / aircraft assembly.There is workpiece flexible clamping, accurate control of pressing force, normal correction and other functions, can meet the high-precision processing needs of high-hard high-brittle material such as ceramic matrix composite.Adopting ultrasonic vibration assisted grinding and laser composite processing mode, processing mode conversion is convenient, significantly reduces the processing difficulty of high-hard high-brittle material, rough machining and special-shaped structure processing adopt water guide laser processing mode, finishing adopts ultrasonic assisted vibration grinding, can remove the heat affected zone of laser processing, ensure final machining precision, solve the contradiction between assembly in-situ machining precision and efficiency of ceramic matrix composite and other materials.

Description

Technical Field

[0001] This invention relates to an online composite machining device for difficult-to-machine materials, used for drilling and trimming of ceramic matrix composites / high-temperature alloys and other materials in aircraft assembly, belonging to the field of aerospace manufacturing engineering / aircraft assembly. Background Technology

[0002] High-temperature alloys (such as GH3536 and GH4169) and continuous fiber-reinforced non-oxide ceramic composites such as C / C, C / SiC, and SiC / SiC are mostly difficult-to-machine materials. To meet the aerodynamic and long-life requirements of high-speed aircraft, various manufacturing technical indicators are demanding, such as quality control of surface clearance differences and the amount of protrusions and concavities in standard parts connections. The extensive use of high-value, difficult-to-machine materials poses a greater challenge to assembly process technology, necessitating the development of assembly processes that can effectively drill and trim difficult-to-machine materials for use in assembly sites.

[0003] Due to the long manufacturing process and the numerous and complex coordination relationships of components, a process compensation allowance is typically left on the skin to ensure proper seam clearances, step differences, and fastener connection variations. This allowance is used to eliminate the cumulative effects of component processing and assembly errors, and is achieved through drilling and trimming at the assembly site to meet design requirements. Compared to traditional aircraft, high-speed aircraft feature significant innovations in material systems and structural forms: a large number of high-temperature resistant materials, such as ceramic matrix composites, high-temperature alloys, and high-temperature titanium alloys, along with their corresponding lightweight and complex structures, will largely replace existing material systems and structures as primary and secondary load-bearing components. The rapid manufacturing, processing, and precise assembly of these new materials and structures pose a severe challenge to the capabilities of existing processing and assembly equipment and process design models. If effective measures are not taken as soon as possible, it will not only severely limit the development progress of new aircraft, but some technology verifications may even be completely impossible to conduct. Ceramic matrix composite parts exhibit high hardness and brittleness. Furthermore, the high value of high-temperature resistant materials and the complexity of their manufacturing processes result in high production costs, placing higher demands on assembly drilling and trimming. Therefore, there is an urgent need to develop high-temperature resistant material processing technologies suitable for assembly, addressing on-site repair and long-life connection issues, increasing the number of aircraft uses, and ensuring flight safety. For difficult-to-machine materials, both domestically and internationally, specialized processing technologies are widely used, such as high-frequency ultrasonic vibration-assisted machining, multi-pulse frequency conversion laser processing, laser melting, water-guided lasers, chemical milling, and thermal cracking. These processes have achieved good application results in the processing of high-temperature alloys and ceramic materials. Summary of the Invention

[0004] The present invention proposes an online robotic composite machining device for difficult-to-machine materials, comprising a robot and a machining actuator. The robot is used to clamp the workpiece and can move and position it over a wide range. The machining actuator frame integrates a composite machining module containing ultrasonic-assisted vibration and water-guided laser. Roughing and machining of irregular structures adopt the water-guided laser machining mode, which significantly reduces the machining difficulty. Finishing adopts ultrasonic-assisted vibration grinding, which can remove the heat-affected zone of laser machining and improve the final machining accuracy.

[0005] This invention relates to an online robotic composite machining device for assembling difficult-to-machine materials. It integrates ultrasonic-assisted vibration and water-guided laser processing technologies. Based on processing requirements, it can perform workpiece clamping, automatic method finding, workpiece positioning, clamping, and processing feed, meeting the needs for machining irregularly shaped holes, high-precision round holes, and three-dimensional curved boundaries. For high-hardness and high-brittleness materials, conventional connection holes and boundaries are mainly processed using laser processing. For fastener mounting holes with high requirements for hole diameter accuracy and heat-affected zone, ultrasonic-assisted vibration is used for precision machining and heat-affected zone removal, meeting differentiated processing needs and ensuring processing accuracy and efficiency.

[0006] According to one aspect of this application, a robotic online composite processing device for difficult-to-process materials is provided, comprising a C-shaped fixture 1, a composite processing system 2, an auxiliary detection system 3, and a robot feeding system 4.

[0007] The C-shaped fixing frame 1 has sufficient rigidity, adopts a C-shaped structure with good openness, and is fixed to the ground by the base 13;

[0008] The upper end of the C-shaped fixing frame 1 is provided with a processing unit interface 11 and a detection unit interface 12, which provide installation interfaces for the composite processing system 2 and the auxiliary detection system 3.

[0009] The composite machining system 2 includes an x-axis drive unit 21, a sliding platform 22, an ultrasonic machining feed unit 23, an ultrasonic-assisted vibration machining unit 24, and a laser machining unit 25.

[0010] The x-axis drive unit 21 adopts a conventional structure and is installed on the machining unit interface 11. It mainly includes a motor, coupling, ball screw, grating ruler, bearing seat, etc., and is used for x-axis drive of the composite machining system.

[0011] The sliding platform 22 is mounted on the processing unit interface 11 via a linear guide rail and a slider, and moves along the x-axis under the drive of the x-axis drive unit 21, with a positioning accuracy of up to 0.01 mm.

[0012] The ultrasonic processing feed unit 23 is mounted on the sliding platform 22 and adopts a conventional structure, mainly including a motor, coupling, ball screw, grating ruler, bearing seat, etc., for ultrasonic-assisted vibration processing z-axis drive;

[0013] The ultrasonic-assisted vibration machining unit 24 is mounted on the sliding platform 22 via a linear guide rail and a slider, and moves along the z-axis under the drive of the ultrasonic machining feed unit 23, with a positioning accuracy of up to 0.01 mm.

[0014] The laser processing unit 25 includes a mounting bracket 251, a module bracket 252, a module motor 253, a movable bracket 254, and a laser processing device 255;

[0015] The mounting bracket 251 is fixedly mounted on the sliding platform 22;

[0016] The module support 252 is connected to the mounting support 251;

[0017] The fixed end of the module motor 253 is connected to the module support 252, and the movable end is connected to the movable support 254, which can realize driving along the y-axis with a positioning accuracy of up to 0.03mm.

[0018] The laser processing equipment 255 is fixedly mounted on the movable support 254. The module motor 253 and the x-axis drive unit 21 perform interpolation motion under the control of the motion control system, which can complete laser processing feed of arbitrary trajectory in the OXY plane, overcome the problem of low robot motion accuracy, and meet the high-precision processing requirements of small-sized features.

[0019] The auxiliary detection system 3 has functions such as normal detection of the processing area of ​​the workpiece to be processed, monitoring of working status and workpiece clamping, and includes a station conversion drive unit 31, a sensor mounting bracket 32, a pressure sensor 33, a normal detection unit 34 and an auxiliary lighting and visual monitoring unit 35.

[0020] The workstation conversion drive unit 31 is installed on the detection unit interface 12 and mainly includes a motor, coupling, ball screw, bearing housing, limit switch, etc., and is used to control the working status of the auxiliary detection system 3.

[0021] The sensor mounting bracket 32 ​​is mounted on the detection unit interface 12 via a linear guide rail and a slider, and moves under the drive of the station conversion drive unit 31 to realize the adjustment of two positions: the working station and the avoidance station. In the laser processing mode, the avoidance station is required, and the rest are the working stations.

[0022] The pressure sensor 33 is installed on the sensor mounting bracket 32 ​​to detect the pressure value in real time and feed it back to the robot feeding system 4 for closed-loop control of the clamping force.

[0023] The normal detection unit 34 is installed on the sensor mounting bracket 32 ​​and is used for online detection of the normal of the area to be processed, and feeds back to the robot feeding system 4 for closed-loop control of processing verticality.

[0024] The auxiliary lighting and visual monitoring unit 35 is mounted on the sensor mounting bracket 32 ​​and is used for workpiece lighting and processing status monitoring, so that the operator can understand the actual processing situation.

[0025] The robot feeding system 4 includes a flexible clamping unit 41, a six-axis robot 42, and a robot mounting base 43.

[0026] The six-axis robot 42 is fixedly installed on the foundation via a robot mounting base 43;

[0027] The flexible clamping unit 41 is fixedly mounted on the flange of the six-axis robot 42, and its positioning and clamping mechanisms are replaceable.

[0028] The workpiece stand is fixedly installed on the flexible clamping unit 41 and completes tasks such as machining positioning, normal adjustment, workpiece clamping, and milling feed with the support of data from the auxiliary detection system 3.

[0029] The composite processing includes ultrasonic-assisted vibration processing and laser processing;

[0030] The laser processing is selected from water-guided laser processing or high-frequency pulsed laser processing.

[0031] The above describes the main body of the invention. Some small parts, standard parts, cables, wiring channels, pipes, vacuum systems, control systems, control software, etc. are not shown.

[0032] The advantages of this application are:

[0033] The online robotic composite machining device for assemblies of difficult-to-machine materials proposed in this invention features flexible workpiece clamping, precise clamping force control, and normal correction functions, meeting the rapid and high-precision machining requirements of high-hardness and high-brittle materials such as ceramic matrix composites. Employing a hybrid approach of ultrasonic vibration-assisted grinding and laser machining, the device allows for convenient switching between machining modes, significantly reducing the machining difficulty of high-hardness and high-brittle materials. Roughing and machining of irregularly shaped structures utilize water-guided laser machining, while finishing employs ultrasonic-assisted vibration grinding, which removes the heat-affected zone from laser machining, ensuring final machining accuracy and resolving the contradiction between accuracy and efficiency in in-situ assembly machining of ceramic matrix composites and other materials. Attached Figure Description

[0034] Figure 1 Schematic diagram of an online composite processing device for difficult-to-machine materials using robots;

[0035] Figure 2 This is a schematic diagram of a robot feeding system;

[0036] Figure 3 This is a schematic diagram of a laser processing unit;

[0037] Figure 4This is a schematic diagram of the auxiliary detection system.

[0038] in:

[0039] 1. C-type fixed frame, 2. Composite processing system, 3. Auxiliary detection system, 4. Robot feed system, 11. Processing unit interface, 12. Detection unit interface, 13. Base, 21. X-axis drive unit, 22. Sliding platform, 23. Ultrasonic processing feed unit, 24. Ultrasonic assisted vibration processing unit, 25. Laser processing unit, 254. Mounting support, 252. Module support, 253. Module motor, 254. Moving support, 255. Laser processing equipment, 31. Station conversion drive unit, 32. Sensor mounting support, 33. Pressure sensor, 34. Normal detection unit, 35. Auxiliary lighting and visual monitoring unit, 41. Flexible clamping unit, 42. Six-axis robot, 43. Robot mounting base. Detailed Implementation

[0040] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0041] Example 1

[0042] The main body of the composite processing device of the present invention includes a C-shaped fixed frame 1 (including a processing unit interface 11, a detection unit interface 12, and a base 13), a composite processing system 2 (including an x-axis drive unit 21, a sliding platform 22, an ultrasonic processing feed unit 23, an ultrasonic-assisted vibration processing unit 24, and a laser processing unit 25, wherein the laser processing unit 25 includes a mounting support 251, a module support 252, a module motor 253, a moving support 254, and a laser processing device 255), an auxiliary detection system 3 (including a station conversion drive unit 31, a sensor mounting support 32, a pressure sensor 33, a normal detection unit 34, and an auxiliary lighting and vision monitoring unit 35), and a robot feeding system 4 (including a flexible clamping unit 41, a six-axis robot 42, and a robot mounting base 43, as shown below). Figures 1-3 As shown, the C-type mounting frame 1 serves as the main platform, on which the composite machining system 2 and auxiliary detection system 3 are integrated and installed. These systems primarily handle machining mode switching, online detection, and composite machining, and are used for high-precision hole making / trimming of difficult-to-machine materials such as ceramic-based composites. The workpiece to be processed is connected to the robot feed system 4, enabling workpiece positioning and large-size movement feed via the robot. The specific implementation method is as follows:

[0043] 1) The C-type fixing bracket 1 is fixedly installed on the ground by the base 13, and the bolts are prevented from loosening by using double nuts.

[0044] 2) Place the x-axis drive unit 21 on the machining unit interface 11 and adjust its axis direction to be parallel to the x-axis, and fix it in place with standard parts such as bolts.

[0045] 3) Referring to the position of the x-axis drive unit 21, the sliding platform 22 is installed on the machining unit interface 11 through the linear guide rail and the slider, and its axis direction is adjusted to be parallel to the x-axis. It is then fixedly connected by standard parts such as bolts.

[0046] 4) Connect the sliding platform 22 and the x-axis drive unit 21 with standard parts such as bolts to ensure smooth movement.

[0047] 5) Install the ultrasonic processing feed unit 23 at the corresponding position on the sliding platform 22, ensuring that its z-axis is parallel, and fix it.

[0048] 6) The ultrasonic-assisted vibration processing unit 24 is mounted on the sliding platform 22 via a linear guide rail and a slider, and connected to the ultrasonic processing feed unit 23 to ensure smooth movement along the z-axis.

[0049] 7) Install laser processing unit 25.

[0050] a) Fix the mounting bracket 251 on the sliding platform 22 and machine the positioning pin hole to ensure the repeatability of positioning accuracy during multiple disassembly and assembly.

[0051] b) Connect the module support 252 to the mounting support 251 to ensure its positional accuracy.

[0052] c) Connect the fixed end of the module motor 253 to the mounting bracket 251 to ensure its positional accuracy.

[0053] d) Connect the movable support 254 to the movable end of the module motor 253 to ensure smooth movement and that the direction of movement is parallel to the y-axis.

[0054] e) Fix the laser processing equipment 255 on the movable support 254 to ensure that the processing laser beam is parallel to the z-axis and determine its position to facilitate the alignment of the coordinate system in subsequent processing.

[0055] 8) Auxiliary detection system 3.

[0056] a) Install the workstation conversion drive unit 31 on the detection unit interface 12 to ensure its position accuracy.

[0057] b) The upper surface of the sensor mounting bracket 32 ​​is mounted on the detection unit interface 12 by means of a linear guide rail and a slider, ensuring that the guide rail is parallel to the y-axis.

[0058] c) Connect the lower end face of the sensor mounting bracket 32 ​​to the station conversion drive unit 31 to ensure smooth movement.

[0059] d) Install the pressure sensor 33 on the sensor mounting bracket 32 ​​to ensure accurate positioning.

[0060] e) Install the normal detection unit 34 on the sensor mounting bracket 32 ​​to ensure accurate positioning.

[0061] f) The auxiliary lighting and visual monitoring unit 35 is mounted on the sensor mounting bracket 32.

[0062] 9) Install robot feeding system 4.

[0063] a) The six-axis robot 42 is fixedly installed on the foundation via the robot mounting base 43.

[0064] b) The flexible clamping unit 41 is fixedly installed on the flange at the end of the six-axis robot 42.

[0065] 10) System testing and calibration.

[0066] a) Power on and check the cables, pipes, controllers, robots, etc. that connect to each system to ensure system reliability.

[0067] b) The relative positional relationship of the composite machining system 2, auxiliary detection system 3, and robot feeding system 4 is calibrated using digital measuring instruments.

[0068] 11) Ceramic matrix composite hole composite processing flow.

[0069] a) The workpiece to be processed is fixedly mounted on the flexible clamping unit 41, and the robot is driven to deliver the workpiece to the processing position.

[0070] b) The auxiliary detection system 3 is adjusted to the working position by the workstation conversion drive unit 31; the six-axis robot 42 adjusts the contact between the workpiece and the pressure sensor 33 and detects the force value in real time to ensure that the workpiece to be processed is effectively clamped.

[0071] c) Maintain the clamping state, detect the normal of the hole area to be processed by the normal detection unit 34, and provide closed-loop control data feedback to the robot controller, thereby driving the six-axis robot 42 to adjust the workpiece so that the normal of the hole area to be processed is parallel to the z-axis.

[0072] d) Simultaneously, the sliding platform 22 is moved by the x-axis drive unit 21, so that the laser processing unit 25 is in the working position, the laser processing mode is started, and the rough hole processing is completed.

[0073] e) Move the sliding platform 22 by the x-axis drive unit 21 to put the ultrasonic-assisted vibration processing unit 24 into the working position, start the ultrasonic-assisted vibration processing mode, complete the hole finishing and remove the heat-affected zone of laser processing.

[0074] f) The system is reset after the processing task is completed.

[0075] 12) Boundary laser processing flow.

[0076] a) The workpiece to be processed is fixedly mounted on the flexible clamping unit 41, and the robot is driven to deliver the workpiece to the processing position.

[0077] b) The normal direction of the hole area to be processed is detected by the normal direction detection unit 34, and closed-loop control data feedback is provided to the robot controller, thereby driving the six-axis robot 42 to adjust the workpiece so that the normal direction of the hole area to be processed is parallel to the z-axis.

[0078] c) The auxiliary detection system 3 is adjusted to the avoidance station by the station conversion drive unit 31;

[0079] d) Move the sliding platform 22 by the x-axis drive unit 21 to put the laser processing unit 25 into the working position and start the laser processing mode.

[0080] e) The workpiece is fed by a six-axis robot 42, and laser processing is performed simultaneously to finally complete the boundary laser processing.

[0081] f) The system is reset after the processing task is completed.

[0082] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions made by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A robotic online composite processing device for difficult-to-machine materials, characterized in that, Includes C-type fixed frame (1), composite processing system (2), auxiliary detection system (3), robot feeding system (4); The C-type fixing frame (1) is fixed to the ground by the base (13); The upper end of the C-type fixing frame (1) is provided with a processing unit interface (11) and a detection unit interface (12) to provide installation interfaces for the composite processing system (2) and the auxiliary detection system (3); The composite machining system (2) includes an x-axis drive unit (21), a sliding platform (22), an ultrasonic machining feed unit (23), an ultrasonic-assisted vibration machining unit (24), and a laser machining unit (25). The x-axis drive unit (21) is installed on the machining unit interface (11) and is used for x-axis drive of the composite machining system; The sliding platform (22) is mounted on the processing unit interface (11) via a linear guide rail and a slider, and moves along the x-axis under the drive of the x-axis drive unit (21), with a positioning accuracy of up to 0.01 mm; The ultrasonic machining feed unit (23) is mounted on the sliding platform (22) and is used for ultrasonic-assisted vibration machining in the z-direction. The ultrasonic-assisted vibration processing unit (24) is mounted on the sliding platform (22) via a linear guide rail and a slider, and moves along the z-axis under the drive of the ultrasonic processing feed unit (23), with a positioning accuracy of up to 0.01 mm; The auxiliary detection system (3) includes a workstation conversion drive unit (31), a sensor mounting bracket (32), a pressure sensor (33), a normal detection unit (34), and an auxiliary lighting and visual monitoring unit (35). The workstation switching drive unit (31) is installed on the detection unit interface (12) and is used to control the working status of the auxiliary detection system (3); The sensor mounting bracket (32) is mounted on the detection unit interface (12) via a linear guide rail and a slider, and moves under the drive of the workstation conversion drive unit (31) to realize the adjustment of the two positions: the working position and the avoidance position. The pressure sensor (33) is installed on the sensor mounting bracket (32) to detect the pressure value in real time and feed it back to the robot feeding system (4) for closed-loop control of the clamping force; The normal detection unit (34) is installed on the sensor mounting bracket (32) for online detection of the normal of the area to be processed and feedback to the robot feeding system (4) for closed-loop control of processing verticality; The auxiliary lighting and visual monitoring unit (35) is installed on the sensor mounting bracket (32) and is used for workpiece lighting and processing status monitoring, so that the operator can grasp the actual processing situation.

2. The robotic online composite processing device for difficult-to-machine materials according to claim 1, characterized in that, The laser processing unit (25) includes a mounting bracket (251), a module bracket (252), a module motor (253), a movable bracket (254), and a laser processing device (255). The mounting bracket (251) is fixedly mounted on the sliding platform (22); The module support (252) is connected to the mounting support (251); The fixed end of the module motor (253) is connected to the module support (252), and the movable end is connected to the movable support (254), which can realize driving along the y-axis and the positioning accuracy can reach 0.03mm; The laser processing equipment (255) is fixedly installed on the movable support (254). The module motor (253) and the x-axis drive unit (21) perform interpolation motion under the control of the motion control system, which can complete laser processing feed of arbitrary trajectory in the OXY plane, overcome the problem of low robot motion accuracy, and meet the high-precision processing requirements of small-size features.

3. The robotic online composite processing device for difficult-to-machine materials according to claim 1, characterized in that, The robot feeding system (4) includes a flexible gripping unit (41), a six-axis robot (42), and a robot mounting base (43).

4. The robotic online composite processing device for difficult-to-machine materials according to claim 3, characterized in that, The six-axis robot (42) is fixedly installed on the foundation via a robot mounting base (43); The flexible clamping unit (41) is fixedly mounted on the flange of the six-axis robot (42); The workpiece to be processed is fixedly installed on the flexible clamping unit (41), and with the data support of the auxiliary detection system (3), the processing positioning, normal adjustment, workpiece clamping and processing feed are completed.

5. The robotic online composite processing device for difficult-to-machine materials according to claim 1, characterized in that, The composite processing includes ultrasonic-assisted vibration processing and laser processing; The laser processing is selected from water-guided laser processing or high-frequency pulsed laser processing.

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