Measuring, grinding and polishing system and method for an automated processing platform of composite covers

Abstract

The measurement grinding and polishing system and method of the composite cover automatic processing platform belong to the field of robot automatic measurement processing equipment and method. The method adopts the measurement grinding and polishing system of the automatic processing platform. The system is composed of a full-view measurement module, a self-adaptive processing module, a dust collection and removal module and an integrated control module. The method adopts a non-contact and contact measurement method according to the characteristics of the complex structure of the composite cover, such as the rib plate, negative curvature, cavity and deep cavity. A double six-degree-of-freedom robot is used for collaborative work, and a constant force processing assembly and a consumable replacement station are provided to realize the conformal constant force polishing of the cover component. Through a servo dust cover and an efficient filtration system, the polishing dust is collected and purified in real time. Based on the process knowledge base and intelligent planning algorithm, the whole process closed-loop control of measurement, planning, polishing and dust removal is realized. The processing efficiency and accuracy are significantly improved, and the foundation for realizing unmanned and intelligent production is laid.

Description

Technical Field

[0001] This invention belongs to the field of robotic automated measurement and processing equipment and methods, and relates to a measurement and polishing system and method for an automated processing platform for composite material covers. It is applicable to the measurement, polishing and processing of the inner and outer surfaces of various types of composite material cover components with stiffeners, negative curvature, and cavities. Background Technology

[0002] Composite material enclosures are key components in various high-end equipment. Their multifunctional coatings require polishing before preparation, a process that directly determines the effectiveness of the component's environmental resistance, high wave transmission, strong stealth, antistatic properties, and low infrared emission. Enclosures come in various types, with rotary enclosures characterized by a high aspect ratio, and irregularly shaped enclosures featuring complex structures such as negative curvature, internal cavities, and ribs. These two types differ significantly in measurement and processing methods. Currently, polishing of composite material enclosure components in high-end equipment still primarily relies on manual methods. While this method is advantageous for complex components, the subjectivity of manual operation leads to inconsistent polishing quality, low efficiency, and the large amounts of dust and noise generated during processing can harm the operator's health. Therefore, to achieve intelligent manufacturing of various types of composite material enclosure components, there is an urgent need to develop an automated measurement and processing integrated platform based on industrial robots. This platform uses highly flexible and rigid industrial robots to replace manual labor, aiming to solve the problem of automated polishing of enclosure components of different sizes and types. To achieve this goal, the system will address the need for precise and automated grinding and polishing by implementing measurement methods for different geometric structures of internal and external surfaces, flexible processing strategies to adapt to different sizes and process requirements, dust collection and removal equipment to deal with harmful dust generated during processing, and technologies to ensure smooth control of the integrated measurement and processing platform.

[0003] The existing patent, CN121340094A, entitled "An Adaptive Grinding and Polishing Production Line for Parts Based on Robot Technology," integrates multi-process robots and a vision system to achieve fully automated operation of parts from identification and transfer to inner and outer ring grinding and polishing, solving the problems of reliance on manual labor and low efficiency in process connection. However, this solution mainly relies on vision for rough compliance checks and lacks a high-precision online measurement and closed-loop feedback mechanism for key features such as part size and contour. Therefore, it cannot monitor and compensate for processing errors, making it difficult to ensure the consistency of part processing quality under mass production.

[0004] The existing patent, CN109483369B, entitled "A Robotic Grinding and Polishing System with Three-Dimensional Vision and Its Control Method," achieves automated grinding and polishing by integrating a 3D vision and robotic system. First, a robot drives a 3D camera to scan the workpiece and acquire point cloud data. After processing with algorithms such as filtering and segmentation, the robot's motion trajectory is generated, ultimately driving the robot to complete the overall grinding and polishing of the curved workpiece. This method is mainly used to improve the automation level and processing quality of curved structure manufacturing. However, this solution has limitations. Specifically, when measuring components with deep cavities or complex concave structures, the 3D camera is prone to data loss due to line-of-sight obstruction, making accurate modeling and processing difficult. Summary of the Invention

[0005] To overcome the shortcomings of existing technologies, and considering the measurement methods for the internal and external surfaces of components with different structural types and the processing methods for different polishing requirements, a measurement and polishing system and method for an automated processing platform for composite material covers has been invented to achieve automated measurement and polishing processing for cover components of different sizes and types. This method employs a measurement and polishing system for an automated processing platform, integrating four functional modules: a holographic measurement module, an adaptive processing module, a dust collection and removal module, and an integrated control module, to realize the automated polishing processing of composite material covers. The system comprises several modules: a holographic measurement module for measuring the internal and external contours of composite material enclosure components; a non-contact, rapid optical measurement method for open, large-area areas; and a contact scanning measurement method for deep cavity areas or optical blind spots to measure the internal surface shape. This combined contact and non-contact approach enables comprehensive measurement of various types and structures of composite material enclosure components. An adaptive processing module facilitates flexible processing of composite material enclosure components, incorporating constant-force processing components for consistent processing. A dust collection and removal module collects, cleans, and discharges harmful dust generated during processing. An integrated control module provides process control and protection for the automated polishing platform, consisting of a hardware and software system. The hardware system processes polishing process data into robot language, generates measurement and final processing trajectories, and handles hardware debugging and control. The software system handles command transmission and reception and human-machine interaction. This system enables automated polishing of different types of composite material enclosure components, effectively improving processing efficiency and consistency.

[0006] The technical solution adopted in this invention is a measurement and polishing method for an automated processing platform for composite material covers. The method is characterized by employing a measurement and polishing system for the automated processing platform. This system is a closed-loop, in-situ integrated system that uses a combination of contact and non-contact measurement methods across the entire range, employs dual-robot constant force adaptive processing, and features responsive dust collection and monitoring, as well as flexible and intelligent integrated control. It is used to achieve automated measurement and polishing of composite material covers. The measurement and polishing system consists of a holographic measurement module 1, an adaptive polishing module 2, a dust collection and removal module 3, and an integrated control module 4.

[0007] The overall measurement module 1 adopts a combination of non-contact and contact measurement methods to measure the internal and external surface structural characteristics of different configurations.

[0008] 1) The non-contact in-situ measurement consists of a 3D structured light measurement scanner 1.1 mounted at the end of the robotic arm of the six-degree-of-freedom measurement robot 1.2, the six-degree-of-freedom measurement robot 1.2, and a vibration isolation table 1.3; the six-degree-of-freedom measurement robot 1.2 guides the 3D structured light measurement scanner 1.1 to perform non-contact scanning of the open area;

[0009] 2) The contact-type in-situ measurement consists of a non-standard parallel robot 1.4, an extension rod 1.5, a contact probe 1.6, a truss 1.7, an X-axis linear guide rail 1.8, and a Z-axis linear guide rail 1.9. The contact probe 1.6 is connected to the end of the non-standard parallel robot 1.4 via the extension rod 1.5. The X-axis linear guide rail 1.8 and the Z-axis linear guide rail 1.9 are mounted on the truss 1.7. The non-standard parallel robot 1.4 guides the contact probe 1.6 to measure its running trajectory, thus completing the contact-type measurement of the internal profile of the deep cavity component.

[0010] The adaptive grinding and polishing module 2 consists of a six-degree-of-freedom machining robot 2.1 mounted on a robot base 2.3, a constant-force machining component 2.2, and a consumable replacement station 2.4. The constant-force machining component 2.2 is mounted at the end of the six-degree-of-freedom machining robot 2.1. The constant-force machining component 2.2 consists of an air mill 2.5, an electric spindle 2.6, a floating device 2.7, an axial disc grinding and polishing tool 2.8, and a radial cylindrical grinding and polishing tool 2.9. The air mill 2.5 is mounted along the floating direction of the floating device 2.7, and the axial disc grinding and polishing tool 2.8 is mounted at its end. The electric spindle 2.6 is mounted perpendicular to the floating direction of the floating device 2.7, and the radial cylindrical grinding and polishing tool 2.9 with a flexible sand ring is mounted at its end.

[0011] The dust collection and removal module 3 consists of a dust removal hood 3.1, a dust removal hose 3.2, a centrifugal fan 3.3, a cartridge dust collector 3.4, an exhaust duct 3.5, and a dust monitoring platform 3.6. The dust removal hood 3.1 is fixed to the end of a six-degree-of-freedom machining robot 2.1 with a custom steel clamp, and cooperates with the air mill 2.5 and electric spindle 2.6 of the constant force machining component 2.2 to perform follow-up dust removal operations while the robot performs grinding and polishing on the hood components. The dust removal hose 3.2 connects the dust removal hood 3.1 and the cartridge dust collector 3.4 to realize the transportation of dust from the collection stage to the treatment stage. The dust monitoring platform 3.6 is set in the discharge section of the exhaust duct 3.5 of the dust removal device, with the sampling port located at the top of the exhaust duct 3.5 to monitor the emission quality.

[0012] The integrated control module 4 is divided into a control hardware system and a software system. The control hardware system adopts a control mode of one industrial-grade computer + PLC integrated control cabinet to generate measurement trajectory and final processing trajectory, and realize the debugging and control of hardware equipment.

[0013] The control software system incorporates a closed-loop error compensation algorithm based on measured point clouds. First, the high-density point cloud data acquired by the overall shape measurement module is compared with the component's theoretical model for optimal fit. The algorithm automatically identifies the global deviation field between the actual surface of the component and the theoretical model, including deformation and uneven allowance characteristics. Based on this deviation field, the preset robot grinding and polishing trajectory is adaptively corrected point-by-point in Cartesian space to generate a conformal trajectory. Finally, the corrected trajectory is sent to the six-degree-of-freedom machining robot for execution. This closed-loop process ensures that the center point of the grinding and polishing tool always fits the actual surface of the component, and the machining accuracy is not affected by the original error of the blank.

[0014] The control software system is responsible for sending and receiving control commands throughout the measurement and processing process and provides a visual operation interface. The measurement trajectory, processing trajectory, and process parameters are all planned by the software, which also undertakes the data transmission, status monitoring, alarm protection, and process knowledge management functions of the entire system.

[0015] The specific steps of the automatic measurement and polishing process are as follows:

[0016] Step 1: Measure the inner and outer surfaces of the rotating cover components to provide accurate data for robot grinding and polishing path planning;

[0017] 1) When measuring the outer contour of the rotary cover component A1 at the outer surface machining station, first place the rotary cover component A1 at the outer surface machining station with its top facing upward in the clamping fixture of the measuring station to determine the relative position of the rotary cover component A1 at the outer surface machining station and the 3D structured light measurement scanner 1.1; then unify the coordinates to the base coordinate system of the six-degree-of-freedom measuring robot 1.2, plan the measurement trajectory according to the model of the rotary cover component A1, and input it into the control system of the six-degree-of-freedom measuring robot 1.2; Next, the motion trajectory coordinates are transformed into the base coordinate system of the six-degree-of-freedom measuring robot 1.2. The six-degree-of-freedom measuring robot 1.2 guides the 3D structured light measuring scanner 1.1 to perform high-precision scanning of the rotary cover component A1 at the outer surface processing station, and obtains the point cloud of the cover component in the coordinate system of the 3D structured light measuring scanner 1.1. The rotary cover component A1 at the outer surface processing station is slowly rotated during the precision measurement of the 3D structured light measuring scanner 1.1, so as to realize the full-area scanning of the outer surface of the rotary cover component A1 at the outer surface processing station.

[0018] 2) When measuring the inner profile of the rotary cover component A2 at the inner surface machining station, no secondary clamping is required. Adjust the rotary cover component A to a measurement posture with the opening facing upwards. Then, move the irregularly shaped parallel robot 1.4 to the measurement station of the rotary cover component A2 at the inner surface machining station along the linear guide 1.8 in the X-axis direction. Then, perform coordinate transformation to move the irregularly shaped parallel robot 1.4... The data from the base coordinate system is converted to the coordinate system of the rotating cover component A to complete the initial pose calibration of the system and the component. Next, a corresponding contact probe 1.6 is selected according to the component size, a safety distance is set, and the measurement position of the measuring head is adjusted using the linear guide rails 1.8 and 1.9 on the X-axis and Z-axis directions on the truss 1.7. The non-standard parallel robot 1.4 guides the contact probe to perform line-by-line contact measurement along the circumference of the rotating cover component A2 at the inner surface processing station, starting from the opening. The above measurement process is repeated along the circumference and at different cross-sectional heights until the full-space inner surface data of the measurement station from the opening to the top is collected. The collected data is then denoised and the surface is reconstructed using dedicated data processing software. Finally, after all measurements are completed, the non-standard parallel robot 1.4 returns to the initial safe position.

[0019] Step 2: After measurement, grinding and polishing are performed; the six-DOF machining robot 2.1 simultaneously processes two rotary cover components A1 and A2; firstly, the grinding and polishing trajectories of the inner and outer surfaces of the rotary cover components A1 and A2 are planned; the poses of the rotary cover components A1 and A2 are transformed to the base coordinate system of the six-DOF machining robot 2.1 through coordinate transformation to complete the position determination of the robot and the cover components; then, the outer surface of the rotary cover component A1 at the outer surface machining station is processed. The grinding and polishing process employs a constant force processing component 2.2 to maintain a constant contact force. The outer surface of the rotating cover component is ground and polished using an air grinder 2.5 that floats parallel to the floating direction of the floating device 2.7. After the outer surface of the rotating cover component A1 at the outer surface processing station is ground and polished, the rotating cover component is flipped to the inner surface grinding and polishing station. First, the rotating cover component A1 at the outer surface processing station is horizontally rotated 180°, at which point the open end of the cover component faces upwards. With the tip facing down, the component flips over to enter the inner surface grinding and polishing station. Finally, the inner surface of the rotating cover component A2 in the inner surface processing station is ground and polished using an electric spindle 2.6 that floats perpendicular to the floating device 2.7, and equipped with an adjustable-length radial cylindrical grinding and polishing tool 2.9. Multi-condition grinding and polishing is performed to overcome the limitations of different diameters, depths, and surface shapes of the cover component. For the outer surface and areas with large curvature, an axial disc mill driven by an air mill 2.5 is used. The polishing tool 2.8 is used, and constant force control is applied along the floating direction of the floating device 2.7 to achieve stable constant force polishing. For deep cavities, the radial cylindrical polishing tool 2.9 is driven by the electric spindle 2.6. The constant force control along its outer edge, combined with the constant force control perpendicular to the floating direction of the floating device 2.7, completes the constant force polishing operation on the inner surface of the deep cavity. The entire automated platform polishing system for a composite material cover realizes a closed-loop operation of "in-situ measurement - conformal polishing" from automatic measurement to polishing processing.

[0020] Step 3: While the robot is grinding and polishing the components of the cover, the dust collection and removal module 3 performs follow-up dust removal operations; the dust hood 3.1 installed at the end of the six-degree-of-freedom processing robot 2.1 draws dust into the cartridge dust collector 3.4 for filtration and dust removal through the dust removal hose 3.2 and centrifugal fan 3.3, and then discharges it at high altitude through the exhaust pipe 3.5. The dust monitoring platform 3.6 performs quality checks on the gas after dust removal.

[0021] Step 4: The integrated control module 4 participates in the planning and control of all stages of the automated platform polishing system for a composite material cover. The control hardware is responsible for the debugging, control, and data acquisition of the hardware equipment, including the six-degree-of-freedom machining robot 2.1, the constant force machining component 2.2, the 3D structured light measurement scanner 1.1, the irregular parallel robot 1.4, the six-degree-of-freedom measurement robot 1.2, and the consumable replacement station 2.4. The control software follows a modular and sequential intelligent control logic in the actual processing flow, and coordinates the entire measurement and processing process through a visual operation interface. The control software is responsible for sending and receiving control commands throughout the measurement and processing process, and provides a visual operation interface, as well as planning for measurement trajectory, processing trajectory, and process parameters. At the same time, it plays a role in data transmission, status monitoring, alarm protection, and process knowledge management during the measurement process. It supports the real-time setting, monitoring, recording, and display of key parameters. Once the parameters reach the protection limit, the software system automatically triggers an alarm and implements protection to ensure the safe and stable operation of the equipment and the processing process.

[0022] Compared with the prior art, the beneficial effects of this invention are:

[0023] 1) This invention achieves high-precision, fully automated, and closed-loop machining of "in-situ measurement-conformal machining" without the need for secondary clamping. Through the design of coordinate system transformation between the holographic measurement module and the adaptive machining module, and the embedded closed-loop error compensation algorithm based on measured point clouds, the system can complete a fully automated closed loop from "in-situ measurement" to "path planning" and then to "precision grinding and polishing" at the same workstation. It first uses a high-precision measurement module to acquire the workpiece's true three-dimensional data, then generates a conformal grinding and polishing trajectory for the robot based on the actual profile, and finally executes the process using the adaptive machining module. This closed-loop process completely changes the traditional model that relies on human experience and fixed templates, significantly improving the accuracy and repeatability of machining, and laying the foundation for unmanned and intelligent production.

[0024] 2) This invention addresses the challenges of poor accessibility and incomplete data acquisition in the measurement and processing of complex components, especially deep-cavity components, and proposes an effective solution. Considering the complex structures of composite material enclosures—including stiffeners, negative curvature, cavities, and deep cavities—the system innovatively integrates both non-contact and contact measurement methods. A 3D structured light measurement scanner is used to rapidly measure large open areas, while a contact probe is mounted on the end effector of a dexterous parallel robot to reach deep cavity areas inaccessible by traditional optical methods. This enables comprehensive data acquisition of the entirety of various types of composite material enclosure components, providing comprehensive and reliable data support for subsequent precision processing.

[0025] 3) This invention significantly improves processing efficiency and quality consistency. The system employs a dual-robot collaborative operation mode, enabling simultaneous parallel processing of multiple workpieces and drastically shortening the production cycle. More importantly, its constant-force processing components maintain a constant contact force during the grinding and polishing process. Combined with the optimization of grinding and polishing process parameters through a process database and database application system, this ensures uniform and controllable material removal. This allows each component in mass production to achieve consistent surface quality, effectively solving the problem of large quality fluctuations in traditional manual grinding and polishing.

[0026] 4) This invention possesses a high degree of flexibility and intelligence. The platform is not designed for a single type of component; its flexibility lies in its ability to quickly adapt to cover components of different models, sizes, and structures. Through modular design and intelligent software systems, it can quickly switch between processing objects. Its intelligence stems from an integrated process knowledge base and database system, which can autonomously reason and plan optimal processing parameters based on historical data and learning algorithms, considering the characteristics of new components. This greatly reduces reliance on operator experience and achieves a shift from manual to automated decision-making.

[0027] 5) This invention ensures production safety and environmental friendliness. The system integrates a highly efficient follow-up dust collection and removal module, with the dust hood directly installed at the end of the robot's grinding and polishing process, greatly reducing dust diffusion. Simultaneously, the equipped dust monitoring platform can monitor the purified exhaust air in real time, not only protecting the occupational health of operators and preventing the risk of combustible dust accumulation, but also protecting precision equipment such as robots from dust pollution and wear, thereby extending the service life of the entire system. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the measurement and polishing system structure of an automated processing platform for composite material covers. 1-Overall measurement module, 2-Adaptive processing module, 3-Dust collection and removal module, 4-Integrated control module.

[0029] Figure 2 This is a diagram illustrating the overall operational architecture of a grinding and polishing system and method for an automated processing platform for composite material covers.

[0030] Figure 3 This is a schematic diagram of the in-situ measurement structure of the inner and outer contours of a rotating cover component as an example.

[0031] Among them, 1.1-3D structured light measurement scanner, 1.2-six-degree-of-freedom measurement robot, 1.3-vibration isolation table, 1.4-irregular parallel robot, 1.5-extension rod, 1.6-contact probe, 1.7-truss, 1.8-linear guide rail in the X-axis direction, 1.9-linear guide rail in the Z-axis direction, A1-rotary cover component of the outer surface machining station, A2-rotary cover component of the inner surface machining station.

[0032] Figure 4 This is a schematic diagram of the machining structure, taking a rotary cover component as an example. In the diagram, 2.1 is a six-DOF machining robot, 2.2 is a constant force machining component, 2.3 is a robot base, 2.4 is a consumable replacement station, A1 is a rotary cover component at the outer surface machining station, and A2 is a rotary cover component at the inner surface machining station.

[0033] Figure 5 This is a schematic diagram of the constant force machining component structure. 2.5 - air mill, 2.6 - electric spindle, 2.7 - floating device, 2.8 - axial disc polishing tool, 2.9 - radial cylindrical polishing tool.

[0034] Figure 6 This is a schematic diagram of the dust collection and removal module structure of an automated grinding and polishing platform. 3.1 - Dust hood, 3.2 - Dust removal hose, 3.3 - Centrifugal fan, 3.4 - Cartridge dust collector, 3.5 - Exhaust duct, 3.6 - Dust monitoring platform. Specific implementation methods

[0035] The specific embodiments of the present invention will now be described in detail with reference to the technical solutions and accompanying drawings.

[0036] This invention discloses an automated platform polishing system for composite material covers, such as... Figure 1 As shown, the automated platform used in this polishing method consists of a holographic measurement module 1, an adaptive processing module 2, a dust collection and removal module 3, and an integrated control module 4.

[0037] The overall architecture diagram of the automated grinding and polishing platform for various types of composite material cover components is as follows: Figure 2As shown, the automated grinding and polishing platform for multi-type composite material enclosure components constructs a complete closed-loop processing flow from acquiring the actual surface shape to adaptive grinding and polishing. This process first acquires the inner and outer surfaces of the enclosure to be processed. After system startup, the integrated control module 4 first performs system self-checks and initialization, confirming that all components communicate normally, the air and power sources are stable, and the safety barriers and emergency stop devices are in a ready state. The operator selects the component model to be processed through a visual operation interface. The software system automatically retrieves the matching theoretical model, measurement template, and initial process parameter package from the process knowledge base to complete the processing task configuration. Subsequently, a six-degree-of-freedom measurement robot 1.2 guides a 3D structured light measurement scanner 1.1 to perform non-contact scanning of the open area. Simultaneously, a parallel robot 1.4 carrying a contact probe 1.6 penetrates deep into cavities and complex structural areas to perform contact measurements, acquiring the actual surface shape data of the entire component. The two sets of measurement data are then processed by the data processing unit in the integrated control module 4 through point cloud stitching, noise reduction, simplification, and coordinate unification to generate a complete actual three-dimensional profile of the component. Based on this, the software system performs best-fit comparison between the actual profile and the theoretical model, automatically identifies the global deviation field, and adaptively corrects the preset grinding and polishing trajectory point by point. It plans the processing path based on the obtained actual surface data, and the six-degree-of-freedom machining robot 2.1 guides the constant-force machining component 2.2 to perform grinding and polishing operations according to measurement data and preset process parameters. Force sensors collect grinding and polishing force data in real time, and the processing status is fed back to the control system through end-effector force pose conversion, achieving closed-loop control. During processing, the dust removal device simultaneously handles the generated dust, and the consumable replacement station automatically switches tools as needed. The control system uniformly schedules and monitors the status of the six-degree-of-freedom machining robot 2.1 and various functional modules to ensure safe and stable equipment operation. After a single component is processed, the system automatically generates a processing quality report containing information such as processing parameters, force control curves, measurement deviations, and dust emission concentration, and stores it in the database, providing data support for subsequent process optimization. This process ensures operational safety through a safety protection system, ultimately achieving intelligent, automated, and flexible grinding and polishing of composite material cover components.

[0038] In-situ measurement of the inner and outer profiles of a rotating cover component, for example: Figure 3As shown, when measuring the outer contour of the rotary cover component A1 at the outer surface processing station, firstly, the rotary cover component A1 is clamped onto the clamping fixture at the outer surface processing station to determine the relative position between the rotary cover component A1 and the 3D structured light measurement scanner 1.1. Then, the coordinates are unified to the base coordinate system of the six-DOF measurement robot 1.2. Based on the model of the rotary cover component A1 at the outer surface processing station, the measurement trajectory is planned and input into the control system of the six-DOF measurement robot 1.2. The measurement trajectory planning comprehensively considers the optimal working depth of field, field of view, and curvature change of the component's outer surface of the 3D structured light measurement scanner 1.1, automatically divides multiple scanning viewpoints, and generates scanning paths with sufficient overlap between adjacent viewpoints to ensure the quality of point cloud stitching. Next, the motion trajectory coordinates are transformed to the base coordinate system of the six-DOF measurement robot 1.2. The six-DOF measurement robot 1.2 guides the 3D structured light measurement scanner 1.1 to perform a high-precision scan of the rotary cover component A1 at the outer surface processing station, acquiring the point cloud of the cover component in the coordinate system of the 3D structured light measurement scanner 1.1. The rotary cover component A1 at the outer surface processing station is then slowly rotated during the precise measurement by the 3D structured light measurement scanner 1.1, achieving a full-area scan of the outer surface of the rotary cover component A1 at the outer surface processing station. After scanning, the measurement data is transmitted in real time to the integrated control module 4. A point cloud preprocessing algorithm automatically filters out flying points and noise, and a complete point cloud model of the component's outer surface is generated through multi-zone point cloud stitching. After the outer profile measurement is completed, in-situ contact measurement of the inner profile, taking the rotary cover component as an example, is performed. The non-standard parallel robot 1.4 is located in a safe position on the right side of the truss 1.7 when no measurement process is being performed. When measuring the inner profile of the rotary cover component A2 at the inner surface machining station, no secondary clamping is required. After the outer surface measurement is completed, the component is directly flipped to an opening-up position by the flipping mechanism within the station, maintaining the same clamping datum and avoiding coordinate system deviations introduced by repositioning from the outset. Next, the non-standard parallel robot 1.4 is moved along the linear guide 1.8 along the X-axis to the measurement station of the rotary cover component A2 at the inner surface machining station. Then, a coordinate transformation is performed to convert the data from the base coordinate system of the non-standard parallel robot 1.4 to the coordinate system of the rotary cover component A2 at the inner surface machining station, completing the initial pose calibration of the system and the component. Secondly, select the appropriate contact probe 1.6 according to the component size. The model of the contact probe 1.6 and the length of the extension rod 1.5 are automatically matched and recommended by the system from the process knowledge base based on the selected component model. Set the safety distance. The safety distance setting is based on the theoretical inner surface of the component and the diameter of the probe. The software system automatically calculates the safe approach height of the probe into the cavity and the circumferential safe feed amount to avoid collision between the probe and the component. In conjunction with the Z-axis linear guide rail 1.9, guide the robot to perform line-by-line contact measurement along the circumferential direction of the rotary cover component A2 of the inner surface processing station from the opening.The above measurement process is repeated along the circumference and at different cross-sectional heights. During the measurement, the three-dimensional coordinate data of the probe is continuously recorded at a fixed sampling frequency until the surface data of the entire space from the opening to the top of the measurement station is collected. The collected data is then denoised and the surface is reconstructed using dedicated data processing software. Finally, after all measurements are completed, the non-standard parallel robot 1.4 returns to its initial safe position.

[0039] The machining of a rotating cover component is as follows: Figure 4As shown, a six-degree-of-freedom machining robot 2.1 is used to simultaneously process two rotating cover components A1 and A2. First, the grinding and polishing trajectories of the inner and outer surfaces of the rotating cover components A1 and A2 are planned. Trajectory planning is automatically completed by the software system of the integrated control module 4. It compares the actual point cloud data obtained by the overall shape measurement module 1 with the theoretical model of the components to calculate the global deviation field. Based on this deviation field, the preset initial grinding and polishing trajectory is corrected point-by-point with normal offset in Cartesian space to generate a conformal grinding and polishing trajectory that fits the actual surface. Simultaneously, the software system automatically allocates process parameters according to the characteristics of different regions to ensure uniform material removal. Next, the poses of the rotating cover components A1 and A2 are transformed to the base coordinate system of the six-degree-of-freedom machining robot 2.1, thus determining the position of the robot and the cover components. Then, the outer surface of the rotary cover component A1 at the outer surface machining station is ground and polished. A constant force machining component 2.2 is used to ensure constant contact force during the grinding and polishing process. The outer surface of the rotary cover component is ground and polished using an air grinder 2.5 that floats parallel to the floating direction of the floating device 2.7. Different models of axial disc grinding and polishing tools 2.8 are selected for different areas of the rotary cover component to perform multi-condition grinding and polishing to adapt to the grinding and polishing environment of different areas. After the outer surface of the rotary cover component A1 at the outer surface machining station is ground and polished, the rotary cover component is flipped to the inner surface grinding and polishing station. First, the rotary cover component A1 at the outer surface machining station is horizontally flipped 180°. At this time, the open end of the cover component is facing upward and the top end is facing downward. After the flipping is completed, it enters the inner surface grinding and polishing station, as shown in the rotary cover component A2 at the inner surface machining station. Finally, the inner surface of the rotary cover component A2 at the inner surface machining station is ground and polished. An electric spindle 2.6, floating perpendicular to the floating device 2.7, is used, along with an adjustable-length radial cylindrical grinding and polishing tool 2.9. Multi-condition grinding and polishing is performed to overcome the limitations of different diameters, depths, and surface shapes of the cover component. During the machining process, the system adopts a zoned machining strategy and adapts the appropriate grinding and polishing tools based on the surface curvature characteristics of different areas of the component. For areas with abrupt changes in curvature and steep slopes at the front end of the outer surface, a small-diameter axial disc polishing tool 2.8 is used for multiple circular scanning polishing operations to ensure high-completeness processing. For small feature areas, a fine polishing process is achieved by tilting the edge of the grinding head. A graded polishing strategy is adopted for the transition area from the head to the middle, with large and medium-diameter axial disc polishing tools 2.8 used sequentially to efficiently remove excess material and make supplementary adjustments. The gentle middle area is processed efficiently with a large-diameter axial disc polishing tool 2.8. For the tail clamping area, different diameter axial disc polishing tools 2.8 are used in combination according to the characteristics of the clamping and non-clamping areas to achieve uniform removal. The inner surface is polished with a radial cylindrical polishing tool 2.9 to follow the shape and float, with a reserved area for manual polishing.

[0040] The structure of constant force machining component 2.2 is as follows: Figure 5As shown, the constant force machining assembly 2.2 is rigidly connected to the end of the six-degree-of-freedom machining robot 2.1 via a flange. The air mill 2.5 and the electric spindle 2.6 are integrated on the floating device 2.7. An axial disc-shaped polishing tool 2.8 is mounted at the end of the air mill 2.5, and a radial cylindrical polishing tool 2.9 is mounted at the end of the electric spindle 2.6. In terms of motion configuration, the floating direction of the air mill 2.5 is parallel to the inherent floating direction of the floating device 2.7, while the floating direction of the electric spindle 2.6 is perpendicular to the inherent floating direction of the floating device 2.7. Based on this design, the module enables specialized processing for different areas of various types of composite material cover components: for outer surfaces and areas with large curvature, the air mill 2.5 drives the axial disc polishing tool 2.8 and performs constant force control along the floating direction of the floating device 2.7 to achieve stable constant force polishing; for deep cavity areas, the electric spindle 2.6 drives the radial cylindrical polishing tool 2.9, and uses its outer edge in combination with constant force control perpendicular to the floating direction of the floating device 2.7 to complete the constant force polishing operation on the inner surface of the deep cavity.

[0041] Dust collection and removal of automated grinding and polishing platforms, such as Figure 6 As shown, when polishing multi-type composite material cover components, the dust hood 3.1 is installed at the end of the six-degree-of-freedom processing robot 2.1. The dust is drawn into the cartridge dust collector 3.4 for filtration and dust removal through the dust removal hose 3.2 and centrifugal fan 3.3, and then discharged at high altitude through the exhaust pipe 3.5. The dust monitoring platform 3.6 can check the quality of the gas after dust removal.

[0042] The integrated control module 4 comprises a control hardware system and a software system. The control hardware system is responsible for controlling and acquiring data from hardware facilities such as the six-degree-of-freedom machining robot 2.1, the constant-force machining component 2.2, the 3D structured light measurement scanner 1.1, the non-standard parallel robot 1.4, the six-degree-of-freedom measurement robot 1.2, and the consumable replacement station 2.4. The software system follows a modular and sequential intelligent control logic in actual processing. It coordinates the entire measurement and processing process through a visual operation interface. The software system is responsible for planning the measurement trajectory, processing trajectory, and process parameters, and sending and receiving control commands in real time. The software system also has comprehensive data transmission, status monitoring, alarm protection, and process knowledge management functions. It supports the real-time setting, monitoring, recording, and display of key parameters. Once the parameters reach the protection limit, the software system automatically triggers an alarm and implements protection to ensure the safe and stable operation of the equipment and the processing process.

Claims

1. A measurement and polishing method for an automated processing platform for composite material covers, characterized in that, This method employs an automated processing platform with a measurement and polishing system that is integrated in-situ with a closed loop. It uses a combination of contact and non-contact measurement methods across the entire domain, dual-robot constant force adaptive processing, follow-up dust collection and dust removal monitoring, and flexible and intelligent integrated control. The measurement and polishing system consists of a full-view measurement module (1), an adaptive polishing processing module (2), a dust collection and removal module (3), and an integrated control module (4), and is used to realize the automated measurement and polishing processing of composite material covers. The overall measurement module (1) adopts a combination of non-contact measurement and contact measurement to measure the internal and external surface structure characteristics of different configurations; 1) The non-contact in-situ measurement consists of a 3D structured light measurement scanner (1.1), a six-degree-of-freedom measurement robot (1.2), and a vibration isolation table (1.3) installed at the end of the robotic arm of the six-degree-of-freedom measurement robot (1.2); the six-degree-of-freedom measurement robot (1.2) guides the 3D structured light measurement scanner (1.1) to perform non-contact scanning of the open area; 2) The contact-type in-situ measurement consists of a non-standard parallel robot (1.4), an extension rod (1.5), a contact probe (1.6), a truss (1.7), an X-axis linear guide (1.8), and a Z-axis linear guide (1.9). The contact probe (1.6) is connected to the end of the non-standard parallel robot (1.4) through the extension rod (1.5). The X-axis linear guide (1.8) and the Z-axis linear guide (1.9) are installed on the truss (1.7). The non-standard parallel robot (1.4) guides the contact probe (1.6) to run, penetrate deep into the cavity and complex structural areas to measure the trajectory, and complete the contact measurement of the internal profile of the deep cavity component. The adaptive grinding and polishing module (2) consists of a six-degree-of-freedom machining robot (2.1), a constant-force machining component (2.2), and a consumable replacement station (2.4) mounted on a robot base (2.3). The constant-force machining component (2.2) is mounted at the end of the six-degree-of-freedom machining robot (2.1). The constant-force machining component (2.2) consists of an air mill (2.5), an electric spindle (2.6), a floating device (2.7), an axial disc grinding and polishing tool (2.8), and a radial cylindrical grinding and polishing tool (2.9). The air mill (2.5) is mounted along the floating direction of the floating device (2.7), and the axial disc grinding and polishing tool (2.8) is mounted at its end. The electric spindle (2.6) is mounted perpendicular to the floating direction of the floating device (2.7), and the radial cylindrical grinding and polishing tool (2.9) with a flexible sand ring is mounted at its end. The dust collection and removal module (3) consists of a dust hood (3.1), a dust removal hose (3.2), a centrifugal fan (3.3), a cartridge dust collector (()), an exhaust pipe (3.5), and a dust monitoring platform (3.6). The dust hood (3.1) is fixed to the end of a six-degree-of-freedom machining robot (2.1) with a custom steel clamp, and cooperates with the air mill (2.5) and electric spindle (2.6) of the constant force machining component (2.2) to perform follow-up dust removal while the robot performs grinding and polishing on the hood components. The dust removal hose (3.2) connects the dust hood (3.1) and the cartridge dust collector (3.4) to realize the transportation of dust from the collection stage to the treatment stage. The dust monitoring platform (3.6) is set in the discharge section of the exhaust pipe (3.5) of the dust removal device, and the sampling port is located at the top of the exhaust pipe (3.5) to monitor the emission quality. The integrated control module (4) is divided into a control hardware system and a software system. The control hardware system adopts a control mode of an industrial-grade computer + PLC integrated control cabinet to generate measurement trajectory and final processing trajectory, and realize the debugging and control of hardware equipment. The control software system embeds a closed-loop error compensation algorithm based on measured point clouds. First, the high-density point cloud data obtained by the overall shape measurement module is compared with the component theoretical model for best fit. The algorithm automatically identifies the global deviation field between the actual surface of the component and the theoretical model, including deformation and uneven allowance characteristics. Based on this deviation field, the preset robot polishing trajectory is adaptively corrected point by point in Cartesian space to generate a conformal trajectory; finally, the corrected trajectory is sent to the six-degree-of-freedom processing robot for execution. This closed-loop process ensures that the center point of the grinding and polishing tool is always in contact with the actual surface of the component, and the processing accuracy is not affected by the original error of the blank; the software system is responsible for sending and receiving control commands throughout the measurement and processing process, and provides a visual operation interface; The measurement trajectory, processing trajectory, and process parameters are all planned by the software, which also undertakes the functions of data transmission, status monitoring, alarm protection, and process knowledge management for the entire system. The specific steps of the automatic measurement and polishing process are as follows: Step 1: Measure the inner and outer surfaces of the rotating cover components to provide accurate data for robot grinding and polishing path planning; 1) When measuring the outer contour of the rotary cover component (A1) at the surface machining station, first place the rotary cover component (A1) at the surface machining station with its top facing upwards in the clamping fixture of the measuring station to determine the relative position of the rotary cover component (A1) at the surface machining station and the 3D structured light measurement scanner (1.1); then unify the coordinates to the base coordinate system of the six-degree-of-freedom measuring robot (1.2), plan the measurement trajectory according to the model of the rotary cover component (A1), and input it into the control system of the six-degree-of-freedom measuring robot (1.2); then... The motion trajectory coordinates are transformed into the base coordinate system of the six-degree-of-freedom measuring robot (1.2). The six-degree-of-freedom measuring robot (1.2) guides the 3D structured light measuring scanner (1.1) to perform high-precision scanning of the rotary cover component (A1) at the surface processing station, obtain the point cloud of the cover component in the coordinate system of the 3D structured light measuring scanner (1.1), and make the rotary cover component (A1) at the surface processing station slowly rotate during the precision measurement of the 3D structured light measuring scanner (1.1), so as to realize the full-domain scanning of the surface of the rotary cover component (A1) at the surface processing station. 2) When measuring the inner profile of the rotary cover component (A2) at the inner surface machining station, no secondary clamping is required. Adjust the rotary cover component (A1) to the measurement posture with the opening facing upwards. Then, move the non-standard parallel robot (1.4) to the measurement station of the rotary cover component (A2) at the inner surface machining station along the linear guide rail (1.8) in the X-axis direction. Then, perform coordinate transformation to convert the data in the base coordinate system of the non-standard parallel robot (1.4) to the coordinate system of the rotary cover component (A1) to complete the initial pose calibration of the system and the component. Next, select the appropriate contact probe (1.6) according to the component size, set the safety distance, and use the truss The X-axis linear guide (1.8) and Z-axis linear guide (1.9) on (1.7) are used to adjust the measurement position of the measuring head. The non-standard parallel robot (1.4) guides the contact probe to perform line-by-line contact measurement along the circumference of the rotary cover component (A2) at the inner surface processing station from the opening. The above measurement process is repeated along the circumference and at different cross-sectional heights until the full space inner surface data of the measurement station from the opening to the top is collected. The collected data is then denoised and the surface is reconstructed using dedicated data processing software. Finally, after all measurements are completed, the non-standard parallel robot (1.4) returns to the initial safe position. Step 2: After measurement, grinding and polishing are performed; the six-degree-of-freedom machining robot (2.1) simultaneously processes two rotary cover components (A1, A2); firstly, the grinding and polishing trajectories of the inner and outer surfaces of the rotary cover components (A1, A2) are planned; the poses of the rotary cover components (A1, A2) are transformed into the base coordinate system of the six-degree-of-freedom machining robot (2.1) through coordinate transformation to complete the position determination of the robot and the cover components; then, the outer surface of the rotary cover component (A1) at the outer surface machining station is processed. The grinding and polishing process is carried out by using a constant force processing component (2.2) to maintain a constant contact force. The outer surface of the rotary cover component is ground and polished using an air grinder (2.5) that floats parallel to the floating device (2.7). After the outer surface of the rotary cover component (A1) at the outer surface processing station is ground and polished, the rotary cover component is flipped to the inner surface grinding and polishing station. The rotary cover component (A1) at the outer surface processing station is first horizontally flipped 180°, and at this time the opening end of the cover component faces the inner surface. With the top tip facing down, the machine flips over to enter the inner surface grinding and polishing station. Finally, the inner surface of the rotary cover component (A2) in the inner surface processing station is ground and polished. An electric spindle (2.6) that floats perpendicular to the floating device (2.7) is used, along with a radial cylindrical grinding and polishing tool (2.9) with adjustable length, to perform multi-condition grinding and polishing to overcome the limitations of different diameters, depths, and surface shapes of the cover component. For the outer surface and areas with large curvature, an axial disc is driven by an air mill (2.5). The polishing tool (2.8) is subjected to constant force control along the floating direction of the floating device (2.7) to achieve stable constant force polishing; for the deep cavity, the radial cylindrical polishing tool (2.9) is driven by the electric spindle (2.6), and its outer edge is combined with constant force control perpendicular to the floating direction of the floating device (2.7) to complete the constant force polishing operation on the inner surface of the deep cavity; the entire automated platform polishing system for a composite material cover realizes the closed-loop operation of "in-situ measurement-conformal polishing" from automatic measurement to polishing processing; Step 3: While the robot is grinding and polishing the components of the cover, the dust collection and removal module (3) performs follow-up dust removal operation; the dust hood (3.1) installed at the end of the six-degree-of-freedom processing robot (2.1) draws dust into the cartridge dust collector (3.4) for filtration and dust removal through the dust removal hose (3.2) and centrifugal fan (3.3), and then discharges it at high altitude through the exhaust pipe (3.5), and the dust monitoring platform (3.6) performs quality checks on the gas after dust removal; Step 4: Throughout the entire operation of the automated platform polishing system for composite material covers, the integrated control module (4) is involved in planning and control. The control hardware is responsible for the debugging, control, and data acquisition of the hardware equipment, including the six-degree-of-freedom processing robot (2.1), constant force processing component (2.2), 3D structured light measurement scanner (1.1), irregular parallel robot (1.4), six-degree-of-freedom measurement robot (1.2), and consumable replacement station (2.4). The control software follows a modular and sequential intelligent control logic in the actual processing flow, and coordinates the entire measurement and processing process through a visual operation interface. The control software is responsible for sending and receiving control commands throughout the measurement and processing process, and provides a visual operation interface to coordinate the entire measurement and processing process, including the planning of measurement trajectory, processing trajectory, and process parameters. At the same time, it plays a role in data transmission, status monitoring, alarm protection, and process knowledge management during the measurement process, and supports the real-time setting, monitoring, recording, and display of key parameters. Once the parameters reach the protection limit, the control software system automatically triggers an alarm to implement protection and ensure the safe and stable operation of the equipment and processing process.

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