Active vibration suppression and deformation compensation device for high-precision thin-wall part machining

Abstract

The invention discloses an active vibration suppression and deformation compensation device for high-precision thin-walled part machining, and relates to the technical field of machining equipment. The device comprises a base module, a clamping positioning module, a multi-source sensing monitoring module, a cooperative actuation vibration suppression module, a multi-point flexible compensation module, an intelligent control module and a machine tool cooperative interface module. The multi-source sensing monitoring module synchronously collects vibration, deformation, cutting force and temperature signals in the machining process. The intelligent control module processes signals and drives the cooperative actuation vibration suppression module (including a piezoelectric actuator group and a voice coil motor follow-up supporting unit) to perform broadband vibration suppression, and meanwhile drives the multi-point flexible compensation module (including a flexible supporting matrix and a path compensation interface) to perform local and overall deformation compensation. Synchronous monitoring and active cooperative control of vibration and deformation are achieved through closed-loop control, the machining precision, the surface quality and the machining efficiency of the thin-wall part are remarkably improved, compatibility is good, and the adaptive range is wide.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mechanical processing equipment, in particular to an active vibration suppression and deformation compensation device for high-precision thin-walled part processing, which is especially suitable for the fields of aerospace, precision instruments, medical equipment, etc. and has important significance for promoting the development of high-precision processing technology in the vibration suppression and deformation compensation of thin-walled parts (such as aircraft engine blades, spacecraft cabin wall plates, precision instrument housings, etc.) with a wall thickness of 1-5 mm in the processes of milling, turning, grinding, etc. BACKGROUND

[0002] With the development of modern manufacturing towards high precision, high reliability and light weight, thin-walled parts are widely used in key fields such as aerospace, precision instruments, medical implants, etc. due to their outstanding advantages of light weight, compact structure and high material utilization rate. For example, the core parts such as aircraft engine blades and spacecraft cabin wall plates are typical high-precision thin-walled structures, and the machining precision directly affects the performance and reliability of the whole machine. However, due to the structural characteristics of thin-walled parts, such as thin wall thickness, low stiffness and low natural frequency, two major problems often occur during machining, which seriously restrict the machining quality and production efficiency.

[0003] First, vibration problem. During the machining process, dynamic loads such as cutting force and cutting vibration can easily cause chatter and forced vibration of the part and tool system, resulting in obvious vibration marks on the surface of the part, which not only reduces the surface quality, but also exacerbates tool wear and shortens tool life. Second, deformation problem. The action of cutting force, thermal effects during the machining process and the release of residual stress inside the part can cause elastic and plastic deformation of the part, resulting in size deviation of the part, and in severe cases, the part may even be directly scrapped, greatly increasing the production cost.

[0004] Currently, for the vibration and deformation control of thin-walled part machining, the industry mainly adopts passive control schemes, which include the following categories:

[0005] 1. Optimize machining process parameters: reduce cutting load by reducing cutting speed and feed rate, etc., thereby suppressing vibration and deformation to some extent. However, this scheme has significant defects. Reducing cutting parameters will significantly reduce machining efficiency and increase processing cost, and for high-precision thin-walled part machining requirements, it is difficult to meet the expected precision requirements through process parameter optimization alone.

[0006] 2. Using passive vibration damping fixtures: This involves adding passive vibration damping elements such as rubber damping pads and spring dampers to the fixture to reduce vibration by consuming vibration energy. However, the vibration damping frequency range of passive damping elements is fixed and cannot adapt to changes in vibration frequency under different machining conditions (such as different cutting parameters or different part sizes), resulting in limited vibration damping effect. Furthermore, passive fixtures can only reduce vibration and cannot compensate for deformations generated in real time during machining, making it difficult to fundamentally solve the problem of out-of-tolerance dimensional accuracy.

[0007] 3. Using a rigid support structure: By adding auxiliary support points, the rigidity of the part during the machining process is improved, thereby reducing vibration and deformation. However, rigid support is prone to over-positioning of the part, resulting in local stress concentration, which may cause new deformation. Moreover, the position and support force of rigid support are fixed and cannot be dynamically adjusted according to the real-time deformation state of the part, resulting in extremely poor adaptability and making it difficult to meet the machining requirements of complex curved thin-walled parts.

[0008] 4. Post-processing correction: This method involves multiple machining steps, including aging treatment after rough machining to release residual stress, followed by finish machining to correct deformation. This approach is cumbersome, has a long processing cycle, low production efficiency, and cannot address the vibration and deformation issues that occur in real-time during machining. It offers limited improvement in machining accuracy for high-precision thin-walled parts and is ill-suited to the high-efficiency production demands of modern manufacturing.

[0009] In recent years, some studies have attempted to address these problems using active control techniques, such as employing piezoelectric actuators for simple vibration suppression or using a single displacement adjustment mechanism for deformation compensation. However, existing active control schemes still have many shortcomings and are difficult to meet the machining requirements of high-precision thin-walled parts, specifically:

[0010] (1) Single monitoring dimension: Most existing active control schemes only monitor and control one of vibration or deformation, and cannot achieve synchronous monitoring and coordinated control of vibration and deformation. Since vibration and deformation affect and couple with each other during the processing, single-dimensional control cannot fundamentally solve the accuracy problem, resulting in insufficient control accuracy.

[0011] (2) Difficulty in achieving both actuator performance: The actuator is the core execution element of active control. The piezoelectric actuator used in the existing scheme has a fast response speed but a limited stroke, which cannot meet the large deformation compensation requirements; the voice coil motor has a large stroke but a poor high-frequency response, which makes it difficult to effectively suppress high-frequency vibration, resulting in the device being unable to adapt to thin-walled parts of different sizes and different processing conditions.

[0012] (3) Poor adaptability of control algorithm: Most existing solutions adopt traditional PID control algorithm. This algorithm has a simple structure and is difficult to cope with the complex working conditions of multiple variables such as cutting force and temperature during the processing. It has poor adaptability and cannot optimize control parameters in real time according to the changes in processing status, resulting in insufficient control stability.

[0013] (4) Low device integration: The existing active control devices have poor coordination among their modules (monitoring module, actuation module, control module) and insufficient compatibility with machine tools, making it difficult to achieve integrated control of machining-vibration suppression-compensation. This requires large-scale modification of existing machine tools, increasing equipment investment costs and limiting their promotion and application.

[0014] Therefore, developing an active vibration suppression and deformation compensation device that can achieve synchronous monitoring and active collaborative control of vibration and deformation, has high response speed, large stroke adaptability, high integration and good compatibility with machine tools, has become the key to solving the problem of high-precision thin-walled parts processing, and has important practical significance and application value for promoting the development of high-end manufacturing industries such as aerospace. Summary of the Invention

[0015] To address the problems of poor vibration suppression and deformation compensation, insufficient adaptability, low integration, and poor machine tool compatibility in existing technologies for machining thin-walled parts, this invention provides an active vibration suppression and deformation compensation device for high-precision machining of thin-walled parts. This device integrates a multi-source sensing monitoring module, a collaborative vibration suppression module, a multi-point flexible compensation module, and an intelligent control module to construct a closed-loop control system of "monitoring-analysis-control-execution-feedback." This enables real-time synchronous monitoring and active collaborative control of vibration and deformation during machining, effectively improving the machining accuracy and surface quality of thin-walled parts. Simultaneously, by optimizing the device's structural design, the device's adaptability and integration are improved, reducing equipment investment costs, increasing machining efficiency, and lowering machining costs.

[0016] To achieve the above-mentioned objectives, the technical solution adopted by the present invention is as follows:

[0017] An active vibration damping and deformation compensation device for high-precision thin-walled parts machining includes a base module, a clamping and positioning module, a multi-source sensing and monitoring module, a coordinated actuation vibration damping module, a multi-point flexible compensation module, an intelligent control module, and a machine tool collaborative interface module. The modules are connected to each other via signal lines and mechanical structures to form a complete closed-loop control system.

[0018] 1. Base Module: Provides a stable mounting support for the entire device, which is a prerequisite for ensuring machining accuracy. It includes a base platform, leveling feet, and reinforcing ribs. The leveling feet are located at the four corners of the bottom of the base platform and adopt a spiral leveling structure with an adjustment range of 0-50mm. By rotating the leveling feet, the levelness of the base platform can be precisely adjusted to ensure the horizontal accuracy of the upper surface of the base platform. The reinforcing ribs are made of I-beams and are located on the lower surface of the base platform. They are evenly distributed in the key stress areas of the base platform to improve the structural rigidity of the base platform and prevent deformation of the base itself during machining, which would affect the machining accuracy of the parts.

[0019] Furthermore, the base platform is made of high-strength cast iron and undergoes two aging treatments (the first is natural aging for no less than 240 hours; the second is artificial aging at a temperature of 200-250℃ for 4-6 hours) to eliminate residual stress. The flatness error of its upper surface does not exceed 0.01mm / m, ensuring the accuracy of the installation benchmark and providing a stable foundation for the subsequent installation of various modules and parts processing.

[0020] 2. Clamping and Positioning Module: Located above the base platform, this module enables precise positioning and reliable clamping of thin-walled parts, preventing displacement during machining and avoiding excessive clamping force that could cause pre-deformation. It includes a flexible fixture base, adaptive positioning pins, a vacuum suction cup, and elastic grippers. The flexible fixture base is fixed to the base platform with high-strength bolts. Its top has a positioning groove adapted to the contour of the thin-walled part. The surface roughness of the positioning groove does not exceed Ra0.8μm, and the clearance is 0.02-0.03mm to ensure initial positioning accuracy. Three to four adaptive positioning pins are symmetrically arranged within the positioning groove of the flexible fixture base, arranged in a triangular or rectangular pattern. These pins are used for radial positioning of the part. A pressure sensor is provided to monitor the positioning pressure in real time. When the positioning pressure exceeds a preset threshold (50N), the intelligent control module issues a warning signal to prevent over-positioning and deformation of the part. The vacuum suction cups are evenly distributed at the bottom of the positioning groove, with a quantity of 4-8. They fix the bottom of the part by negative pressure adsorption. The adsorption force of the vacuum suction cups can be adjusted by an electromagnetic control valve, with an adjustment range of 0-200N, to adapt to thin-walled parts of different materials and thicknesses. The elastic pressure claws are set on the edge of the flexible clamping seat, with a quantity of 2-4. They are driven by a cylinder to press the top edge of the part. The pressure head of the elastic pressure claw is made of silicone rubber with a hardness of Shore A50-A60 to avoid damaging the surface of the part. At the same time, the elastic structure can buffer the clamping force and prevent excessive local pressure.

[0021] Furthermore, the adaptive positioning pin includes a positioning rod, a spring, and a pressure sensor. The positioning rod is fitted into the mounting hole of the flexible fixture seat, the spring is located at the bottom of the positioning rod, and the pressure sensor is installed below the spring. The top of the positioning rod has a chamfer of 15°-30° to facilitate the insertion and positioning of the part. When the part is placed in the positioning groove, the positioning rod fits against the surface of the part under the action of the spring. The pressure sensor collects the compression force of the spring in real time to realize real-time monitoring and feedback of the positioning pressure.

[0022] 3. Multi-source sensing monitoring module: Used to collect multi-dimensional data such as vibration, deformation, cutting force, and temperature during the machining process in real time, providing decision-making basis for the intelligent control module. It includes a vibration monitoring unit, a deformation monitoring unit, a cutting force monitoring unit, and a temperature monitoring unit. The vibration monitoring unit includes multiple acceleration sensors, installed on the flexible fixture, the actuator end of the collaborative vibration suppression module, and the machine tool spindle, with 3-5 sensors respectively. These sensors collect vibration acceleration signals from different locations, with a monitoring frequency range of 0-20kHz and a sampling frequency up to 1kHz, comprehensively capturing the vibration state during machining. The deformation monitoring unit includes a laser displacement sensor and strain gauges. The laser displacement sensor is installed next to the machining area via an adjustable bracket, employing the laser triangulation principle. Its measurement range is 0-500mm, with a measurement accuracy of ±1μm and a sampling frequency of 1kHz, used for non-contact monitoring of the part surface. Displacement deformation measurement avoids damage to the part surface caused by contact measurement; strain gauges are attached to key deformation areas of the part (such as blade tips, blade roots, and wall plate edges), with a quantity of 4-6 gauges and a sensitivity coefficient of 2.10-2.20, to collect strain signals of the part and assist in judging the degree and direction of deformation; the cutting force monitoring unit uses a three-dimensional piezoelectric force sensor, installed between the flexible fixture and the base platform, to collect X / Y / Z axis cutting force signals in real time during the cutting process, with a measurement range of 0-5kN and an accuracy of ±0.1%FS, which can accurately capture the variation law of cutting force and provide data support for the prediction of vibration and deformation; the temperature monitoring unit uses an infrared thermometer, installed next to the laser displacement sensor, with a measurement range of -20-1200℃, an accuracy of ±1℃, and a sampling frequency of 100Hz, to monitor the temperature changes in the part's machining area in real time and capture the influence of thermal deformation on machining accuracy.

[0023] 4. Cooperative Vibration Suppression Module: This module is used for active vibration suppression during the machining process. Through the coordinated action of multiple actuators, it covers a wide frequency range of vibration suppression. It includes a piezoelectric actuator group, a voice coil motor follower support unit, and a damping adjustment unit. The piezoelectric actuator group, consisting of 4-8 units, is evenly distributed at the bottom of the flexible fixture base and connected to the base platform. Each piezoelectric actuator has a maximum output displacement of 0-50 μm, a maximum output force of 0-5 kN, and a response time of 1 μs, used to suppress high-frequency vibrations (500 Hz-20 kHz). The piezoelectric actuators are connected in parallel and can operate individually or collaboratively based on vibration monitoring signals to achieve precise high-frequency vibration suppression. The voice coil motor follower support unit is adjustable... The support brackets are installed on the side of the processing area, with 2-4 brackets in total. Each bracket has an arc-shaped support head at its output end. The support head surface is made of flexible material to conform to the part surface. The voice coil motor has a stroke range of 0-50mm, a thrust of 0-100N, and a positioning accuracy of ±0.5μm. It is used to suppress low-frequency vibrations (0-500Hz) and provide follow-up support, adjusting the support position in real time according to the part's processing trajectory. The damping adjustment unit includes an electromagnetic damper and a dedicated controller. The electromagnetic damper is installed on the bracket of the voice coil motor follow-up support unit. The damping coefficient adjustment range is 0-50N·s / m. It can adjust the damping coefficient in real time according to the vibration monitoring signal to improve vibration suppression and prevent resonance.

[0024] Furthermore, the arc-shaped support head surface of the voice coil motor follower support unit is equipped with a pressure sensor with a measurement range of 0-100N and an accuracy of ±0.1N. It can monitor the contact pressure between the support head and the surface of the part in real time. When the contact pressure exceeds the preset threshold, the intelligent control module adjusts the output force of the voice coil motor to avoid excessive support force that could cause deformation of the part.

[0025] 5. Multi-point Flexible Compensation Module: Used to achieve active deformation compensation during processing. Through multi-point support and path correction, it achieves comprehensive compensation for both local and overall deformation. It includes a flexible support matrix, an electric push rod adjustment unit, and a path compensation interface. The flexible support matrix consists of multiple independent flexible support units, evenly distributed below the non-processed area of ​​the part, with 6-12 units in total. Each flexible support unit includes a support rod, a pressure sensor, and a micro servo motor. The top of the support rod adopts a spherical structure to adapt to the curved surface of the part. The pressure sensor is used to monitor the support force in real time, with a measurement range of 0-100N and an accuracy of ±0.1N. The micro servo motor... The machine is used to drive the support rod to move up and down. The adjustment range of the support rod is 0-20mm, and the adjustment accuracy can reach ±0.5μm, so as to achieve precise adjustment of the support height. The electric push rod adjustment unit is set on both sides of the flexible fixture seat, with a quantity of 2 units. The stroke is 0-100mm, the thrust is 0-500N, and the positioning accuracy is ±0.1mm. It is used to adjust the overall posture of the flexible fixture seat and assist in compensating for the overall deformation of the part. The path compensation interface is connected to the machine tool CNC system and adopts an EtherCAT bus interface. It can convert the deformation compensation signal into the correction command of the machine tool tool path, realize the real-time adaptive adjustment of the tool path, and compensate for deformation error from the source of machining.

[0026] 6. Intelligent Control Module: This is the core control unit of the device, responsible for data processing, decision analysis, and command output. It includes a data acquisition card, an industrial controller, an algorithm processing unit, and a power supply module. The data acquisition card connects to the sensors of the multi-source sensing monitoring module. It uses a 16-bit resolution high-speed data acquisition card with a sampling rate of 1MS / s, capable of simultaneously acquiring 16 analog signals. This data acquisition card converts the analog signals acquired by the sensors into digital signals and transmits them to the industrial controller. The industrial controller adopts an integrated architecture of PLC and motion controller. The PLC is responsible for logic control (such as clamping and positioning, equipment start / stop, fault warning, etc.), while the motion controller is responsible for the precise motion control of the actuators. The two interact via a bus to ensure the real-time performance and accuracy of control commands. The algorithm processing unit is integrated into the industrial controller and includes signal preprocessing algorithms, vibration and deformation recognition algorithms, and collaborative control algorithms. The predictive model employs a Kalman filter algorithm for signal preprocessing to filter and denoise the monitoring data, improving data accuracy. The vibration and deformation identification algorithm uses Fast Fourier Transform (FFT) to extract characteristic parameters such as vibration frequency and amplitude, and fits the deformation curve using the least squares method to obtain the deformation amount and direction. The collaborative control algorithm combines Active Disturbance Rejection Control (ADRC) and Model Predictive Control (MPC) to generate vibration suppression and compensation commands based on characteristic parameters, ensuring control stability and accuracy. The predictive model, based on a BP neural network algorithm, is trained using historical data from over 100 different processing conditions. It can predict vibration and deformation trends based on historical processing data, adjust control parameters in advance, and improve control response speed. The power supply module provides stable power to each module, including a high-voltage power supply (powering piezoelectric actuators, output voltage 0-1000V DC), a DC power supply (powering voice coil motors, servo motors, etc., output voltage 24V DC / 10A), and a UPS backup power supply (capacity 1kVA) to ensure safe shutdown of the equipment in the event of a sudden power outage.

[0027] Furthermore, the intelligent control module also includes a human-machine interface, which adopts a 12-inch touch screen that can display monitoring data (vibration acceleration, deformation, cutting force, temperature, etc.), control parameters (support force, actuator displacement, damping coefficient, etc.) and equipment operating status (normal, warning, fault) in real time. It supports operators to manually set control parameter thresholds and start / stop equipment operation, and also has fault recording and query functions to facilitate equipment maintenance and management.

[0028] 7. Machine Tool Collaboration Interface Module: This module enables information interaction and collaborative control between the device and the machine tool, ensuring synchronization between the device's vibration suppression and compensation actions and the machine tool's cutting actions. It includes a communication interface and a synchronization control unit. The communication interface uses an EtherCAT bus interface with a transmission rate of 100Mbps, enabling high-speed data transmission between the device and the machine tool's CNC system, and supports compatibility with mainstream machine tool CNC systems (such as FANUC 31i-B, Siemens 840D sl, etc.). The synchronization control unit synchronizes the device's monitoring, vibration suppression, and compensation actions with the machine tool's cutting actions. It collects the machine tool spindle speed signal and feed axis position signal, transmitting them to the industrial controller. The industrial controller adjusts the timing of control command output based on the machine tool's operating status to ensure the coordination of the machining process, with a synchronization error not exceeding 1ms.

[0029] Furthermore, the device also includes a protective module, which comprises a transparent protective cover and a chip collection trough. The transparent protective cover is made of acrylic material with a thickness of 8mm and is set around the processing area to prevent cutting chips from splashing and to protect operators and equipment. The chip collection trough is made of stainless steel, has a U-shaped cross-section, a width of 100mm, and a depth of 50mm, and is set around the base platform. It has a chip discharge port at the bottom to facilitate the collection and discharge of cutting chips and reduce the impact of chips on the processing.

[0030] III. Beneficial Effects

[0031] Compared with the prior art, the present invention has the following significant advantages:

[0032] 1. Achieving synchronous monitoring and coordinated control of vibration and deformation, significantly improving control accuracy: This invention integrates multi-dimensional monitoring units such as vibration, deformation, cutting force, and temperature through a multi-source sensing monitoring module. This allows for real-time and comprehensive acquisition of multi-source data during the machining process, providing a complete understanding of the part's machining status. The intelligent control module employs a fusion-based coordinated control algorithm, driving the coordinated action of the vibration suppression module and the multi-point flexible compensation module to simultaneously achieve vibration suppression and deformation compensation, fundamentally overcoming the limitations of existing technologies that only control vibration or deformation individually. Experimental verification shows that this device can suppress vibration amplitude within ±5μm, reduce deformation to below 10μm, achieve a part surface roughness below Ra0.8μm, and reach dimensional accuracy of IT5 level, fully meeting the machining requirements of high-precision thin-walled parts.

[0033] 2. Wide adaptability, balancing response speed and stroke: The collaborative vibration suppression module of this invention adopts a collaborative architecture of piezoelectric actuator assembly and voice coil motor follower support unit. The piezoelectric actuator has a fast response speed (μs level) and can effectively suppress high-frequency vibrations from 500Hz to 20kHz; the voice coil motor has a large stroke (0-50mm) and can effectively suppress low-frequency vibrations from 0-500Hz and provide follower support. Together, they can cover a wide frequency vibration range of 0-20kHz, adapting to thin-walled parts of different wall thicknesses (1-5mm) and sizes; the flexible support matrix of the multi-point flexible compensation module can adapt to the surface of parts with different contours, and the electric push rod adjustment unit and path compensation interface work together to achieve comprehensive compensation for local and overall deformation, adapting to various processing methods such as milling, turning, and grinding, greatly improving the adaptability of the device.

[0034] 3. Strong adaptability and high control stability: The intelligent control module of this invention integrates a machine learning prediction model based on BP neural network. It can learn the vibration and deformation patterns under different processing conditions (such as different cutting parameters, different part materials, and different processing methods) based on historical processing data, predict vibration and deformation trends in advance, and actively adjust control parameters to achieve adaptive control. At the same time, the signal preprocessing algorithm can effectively filter noise in the monitoring data, improve data accuracy, and the integrated collaborative control algorithm can cope with complex working conditions with multiple variables such as cutting force and temperature, ensuring that the device can operate stably under different processing conditions and has high control reliability.

[0035] 4. High integration, good compatibility with machine tools, and broad application prospects: This invention uses an EtherCAT bus interface and a synchronous control unit through a machine tool collaborative interface module to achieve high-speed data transmission and motion synchronization with mainstream machine tool CNC systems. It can be directly integrated into existing processing equipment without large-scale machine tool modifications, reducing equipment investment costs. The device's human-machine interface is simple and intuitive, easy to operate, and easy for operators to master quickly. It has low maintenance costs and good application prospects.

[0036] 5. Improved processing efficiency and reduced processing costs: By effectively suppressing vibration and compensating for deformation, this device can significantly improve cutting parameters (such as feed rate, which can be increased by 20%-50%) while ensuring processing accuracy, thus greatly improving processing efficiency. At the same time, the effective control of vibration and deformation reduces the rework and scrap rate of parts (the rework rate can be reduced from more than 15% in the existing technology to less than 2%), extends tool life (tool life can be increased by more than 30%), and reduces processing costs. It is suitable for processing high-precision thin-walled parts in small batches of various products, which meets the development needs of modern manufacturing industry. Attached Figure Description

[0037] Figure 1This is a simplified schematic diagram of the overall structure of the present invention;

[0038] Figure 2 This is a block diagram of the control system principle of the present invention;

[0039] Figure 3 This is a schematic diagram of the active vibration suppression and deformation compensation closed-loop control process of the present invention;

[0040] Figure 4 This is a schematic diagram of the multi-source sensing monitoring process of the present invention;

[0041] Figure 5 This is a schematic diagram of the actuator coordinated control process of the present invention.

[0042] The following are the labeling instructions in the diagram: 1. Base module; 11. Base platform; 12. Leveling support; 2. Clamping and positioning module; 21. Flexible fixture seat; 22. Adaptive positioning pin; 3. Multi-source sensor monitoring module; 31. Vibration monitoring unit; 32. Deformation monitoring unit; 4. Cooperative actuation vibration suppression module; 41. Piezoelectric actuator group; 42. Voice coil motor follow-up support unit; 5. Multi-point flexible compensation module; 51. Flexible support matrix; 6. Intelligent control module; 7. Machine tool collaborative interface module; 8. Thin-walled part. Detailed Implementation

[0043] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] Example 1: Active vibration damping and deformation compensation device for aero-engine blade manufacturing

[0045] This embodiment designs an active vibration damping and deformation compensation device for the milling of aero-engine blades (wall thickness 2-3mm, material TC4 titanium alloy, outline dimensions 500mm×150mm×2.5mm). The specific structure and parameters are as follows:

[0046] 1. Base Module 1: The base platform 11 is made of high-strength cast iron (HT300) with dimensions of 1200mm×800mm×200mm. It undergoes two aging treatments to eliminate residual stress, and the flatness error of the upper surface is 0.008mm / m. The leveling legs 12 adopt a spiral leveling structure with an adjustment range of 0-50mm. There are 4 legs in total, which are installed at the four corners of the bottom of the base platform 11. The reinforcing ribs adopt an I-beam structure with a total of 6 ribs, which are evenly distributed on the lower surface of the base platform 11 and welded to the base platform 11 to improve the structural rigidity.

[0047] 2. Clamping and Positioning Module 2: The flexible clamping seat 21 is made of aluminum alloy (6061-T6) and is fixed to the base platform 11 by M12 high-strength bolts. The top positioning groove is machined according to the contour of the aero-engine blade, with a fitting clearance of 0.02mm. There are 3 adaptive positioning pins 22, which are distributed in a triangle in the positioning groove. The positioning rod 221 has a diameter of 8mm and a length of 50mm. The elastic coefficient of the spring 223 is 5N / mm. The pressure sensor 223 adopts the 1-KS series of HBM, with a measurement range of 0-50N and an accuracy of ±0.1N. There are 4 vacuum suction cups 23, which are evenly distributed at the bottom of the positioning groove. The suction force of each suction cup is 0-200N. The negative pressure is controlled by the VFM series electromagnetic control valve of SMC. There are 2 elastic pressure claws 24, which are symmetrically arranged on both sides of the flexible clamping seat 21. The cylinder model is SC63×50, and the pressure head is made of silicone rubber with a hardness of Shore A50.

[0048] 3. Multi-source sensing monitoring module 3: The vibration monitoring unit 31 uses three PCB company 356A16 type accelerometers 311, which are respectively installed on the side of the flexible fixture 21, the end of the support head of the voice coil motor follower support unit 42, and the tool holder of the machine tool spindle. The measurement range is 0-50g, and the frequency response is 0.5-20kHz. The deformation monitoring unit 32 uses Keyence company IL-600 type laser displacement sensor 321, with a measurement range of 0-300mm, an accuracy of ±1μm, and a sampling frequency of 1kHz. It is installed above the processing area via an adjustable bracket, and the laser beam is perpendicular to the blade processing surface. The strain gauge 322 uses BX120- The 3AA type, consisting of four pieces, is respectively attached to key deformation areas such as the blade tip, blade root, leading edge, and trailing edge, with a sensitivity coefficient of 2.10. The three-dimensional piezoelectric force sensor 331 of the cutting force monitoring unit 33 is a Kistler 9257B model, installed between the flexible fixture seat 21 and the base platform 11, with a measurement range of 0-5kN for each of the X / Y / Z axes and an accuracy of ±0.1%FS. The infrared thermometer 341 of the temperature monitoring unit 34 is a Fluke Ti400+ model, with a measurement range of -20-1200℃, an accuracy of ±1℃, and a sampling frequency of 100Hz, installed on the bracket of the laser displacement sensor 321, with the temperature measurement point aligned with the machining cutting area.

[0049] 4. Collaborative Vibration Suppression Module 4: The piezoelectric actuator group 41 uses PI's P-885.91 type piezoelectric actuators, a total of 6, evenly distributed at the bottom of the flexible clamp seat 21. Each actuator has a maximum output displacement of 0-50μm, a maximum output force of 5kN, and a response time of 1μs. It is powered by PI's E-809 type high-voltage power supply with a voltage range of 0-1000V; the voice coil motor follower support unit 42 uses BEI... The system uses two Kimco LA12-8-000A-2 voice coil motors, with a stroke of 0-50mm, a thrust of 0-100N, and a positioning accuracy of ±0.5μm. The arc-shaped support head 421 has an arc of R50mm, and strain gauges are attached to the surface to monitor contact pressure. The bracket uses a ball screw to adjust the height, with an adjustment range of 0-300mm. The electromagnetic damper 431 of the damping adjustment unit 43 is a Lord RD-8000 model, with a damping coefficient adjustment range of 0-50N·s / m. The damping coefficient is adjusted in real time through a dedicated controller.

[0050] 5. Multi-point flexible compensation module 5: The flexible support matrix 51 consists of 8 flexible support units 511, arranged in a rectangle below the non-machined area of ​​the blade. The support rod 5111 of each flexible support unit 511 has a diameter of 6mm, is made of hard alloy (WC-Co), has an adjustment range of 0-20mm, and an adjustment accuracy of ±0.5μm; the pressure sensor 5112 adopts the 1-KS series from HBM, with a measurement range of 0-100N and an accuracy of ±0.1N; the micro servo motor 5113 adopts the MSMF012L1U2M type from Panasonic, with a rated speed of 3000rpm; the electric push rod adjustment unit 52 adopts the Electrak® from Thomson. Two HD-type tools are installed at both ends of the flexible fixture base 21, with a stroke of 0-100mm, a thrust of 0-500N, and a positioning accuracy of ±0.1mm. The path compensation interface 53 adopts Beckhoff's EK1100 EtherCAT bus interface and is connected to the machine tool CNC system (FANUC 31i-B type) to realize real-time correction of the tool path.

[0051] 6. Intelligent Control Module 6: The data acquisition card 61 adopts the NI PXIe-6368, with a sampling rate of 1MS / s and a resolution of 16 bits, capable of simultaneously acquiring 16 analog signals; the industrial controller 62 adopts an integrated architecture of Siemens S7-1511C PLC and SIMOTION D435 motion controller, with the PLC responsible for logic control and the motion controller responsible for precise motion control of the actuators; the algorithm processing unit 63 uses Kalman filtering for signal preprocessing, Fast Fourier Transform (FFT) and least squares for vibration and deformation recognition, and a fusion algorithm of Active Disturbance Rejection Control (ADRC) and Model Predictive Control (MPC) for cooperative control, with a sampling period of 1ms; the prediction model is based on a BP neural network algorithm, trained using historical data from 120 sets of different processing conditions; the power supply module 64 includes a PI E-809 high-voltage power supply (output 0-1000V DC) and a Mean Well NES-200-24 DC power supply (output 24V). The system features a DC / 10A UPS and a C1K UPS backup power supply from SANTAK (capacity 1kVA). The human-machine interface 65 uses a Weintek MT8121iE touch screen, which is 12 inches in size and can display monitoring data and equipment operating status in real time.

[0052] 7. Machine Tool Collaboration Interface Module 7: Communication interface 71 adopts Beckhoff EK1100 EtherCAT bus coupler with a transmission rate of 100Mbps; Synchronization control unit 72 adopts Siemens Synchronization Manager, which realizes the synchronization of the device and the machine tool cutting action by acquiring the spindle speed signal (3000rpm) and feed speed signal (500mm / min), with a synchronization error of no more than 1ms.

[0053] 8. Protective Module 8: The transparent protective cover 81 is made of acrylic material with a thickness of 8mm and a size of 1500mm×1000mm×800mm. It is fixed to the edge of the base platform 11 by bolts. The debris collection trough 82 is made of stainless steel (304) with a U-shaped cross section, a width of 100mm and a depth of 50mm. It is set around the base platform 11 and has a chip discharge port at the bottom.

[0054] The working process of this embodiment is as follows (in conjunction with...) Figure 3 (Closed-loop control process)

[0055] Step 1: Equipment Debugging and Pre-processing. The operator starts the device through the human-machine interface 65 and adjusts the base platform 11 to a horizontal state by adjusting the leveling feet 12 (levelness error ≤ 0.01mm / m); the aero-engine blade is placed in the positioning groove of the flexible clamp seat 21, the adaptive positioning pin 22 achieves radial positioning, and the pressure sensor 223 monitors the positioning pressure in real time (ensuring the positioning pressure ≤ 50N) to avoid over-positioning; the vacuum suction cup 23 is started, and the suction force is adjusted to 150N to fix the bottom of the blade by negative pressure suction, and the elastic pressure claw 24 is controlled to press the top edge of the blade, and the clamping force is adjusted to 80N to complete the clamping and positioning; the deformation and vibration trends during the blade milling process are predicted by ABAQUS finite element analysis software, and the control parameter thresholds are set in the human-machine interface 65: vibration amplitude threshold ±5μm, deformation threshold 10μm, support force range 10-50N, piezoelectric actuator maximum output displacement 50μm, and voice coil motor stroke range 0-50mm.

[0056] Step 2: Processing Start-up and Synchronization Preparation. The operator starts the machine tool milling operation. The synchronization control unit 72 of the machine tool collaborative interface module 7 collects the machine tool spindle speed and feed rate signals and transmits them to the industrial controller 62 to achieve synchronization between the device and the machine tool. The intelligent control module 6 issues commands to activate the sensors of the multi-source sensing monitoring module 3 to begin real-time collection of various data during the processing (combined with...). Figure 4 (Multi-source sensing monitoring process).

[0057] Step 3: Real-time monitoring and data processing. The sensors in the multi-source sensing monitoring module 3 collect data at preset frequencies: the accelerometer 311 collects real-time vibration acceleration signals from the flexible fixture 21, the actuator end, and the machine tool spindle; the laser displacement sensor 321 non-contactly collects the displacement deformation of the blade's machined surface; the strain gauge 322 collects strain signals from key areas of the blade; the three-dimensional piezoelectric force sensor 331 collects X / Y / Z axis cutting force signals during milling; the infrared thermometer 341 collects temperature signals from the machining area; the data acquisition card 61 converts the analog signals from each sensor into digital signals and transmits them to the industrial controller 62; the algorithm processing unit 63 uses a Kalman filter algorithm to filter and denoise the data, removing environmental interference and sensor noise; the vibration frequency and amplitude are extracted using FFT (in this embodiment, the monitored vibration frequency is 1200Hz and the amplitude is 8μm), and the deformation curve is fitted using the least squares method, yielding a deformation of 15μm, with the deformation direction being downward bending of the blade tip.

[0058] Step 4: Active vibration suppression and deformation compensation control. Based on the processed monitoring data, the industrial controller 62 determines that the vibration amplitude (8μm) exceeds the threshold (±5μm) and the deformation (15μm) exceeds the threshold (10μm). It then initiates the collaborative control algorithm to generate vibration suppression and compensation commands (combined with…).Figure 5 (Actuator coordinated control process)

[0059] (1) Vibration suppression control: For the high-frequency vibration of 1200Hz, the industrial controller 62 sends a control command to the piezoelectric actuator group 41, and the high voltage power supply outputs a reverse voltage (800V) to drive the six piezoelectric actuators to output a reverse displacement of 3μm to cancel the high-frequency vibration; at the same time, the industrial controller 62 sends a command to the voice coil motor follower support unit 42, and the voice coil motor drives the arc support head 421 to fit against the blade surface to provide follower support, and the support force is adjusted to 30N; the damping adjustment unit 43 adjusts the damping coefficient of the electromagnetic damper 431 to 30N·s / m according to the vibration signal to further suppress the vibration. After 0.5s of adjustment, the vibration amplitude drops to 3μm, which meets the threshold requirement.

[0060] (2) Deformation compensation control: Based on the deformation amount (15μm) and the deformation direction (the blade tip bends downward), the industrial controller 62 sends a control command to the multi-point flexible compensation module 5: Among the eight flexible support units 511 of the flexible support matrix 51, the micro servo motors 5113 of the two support units in the blade tip region drive the support rods 5111 to move upward by 12μm, and the support force is adjusted to 30N; the support rods 5111 of the two support units in the blade root region move upward by 3μm, and the support force is adjusted to 40N; the remaining four support units keep the support force unchanged at 20N, and the local deformation is offset by multi-point differentiated support; at the same time, the electric push rod adjustment unit 52 adjusts the posture of the flexible fixture seat 21, so that the front end of the fixture seat tilts upward by 0.005° to compensate for the overall deformation; the path compensation interface 53 sends a tool path correction command to the machine tool CNC system to correct the Z-axis feed of the tool by 0.01mm, further ensuring the machining dimension accuracy; after 1s of adjustment, the deformation amount is reduced to 8μm, which meets the threshold requirement.

[0061] Step 5: Closed-loop feedback and dynamic adjustment. The multi-source sensor monitoring module 3 continuously collects data during the machining process and transmits the data to the industrial controller 62 every 1ms. The industrial controller 62 compares the actual monitored values ​​with the set thresholds in real time and dynamically corrects the vibration suppression and compensation commands to achieve closed-loop control. The predictive model predicts the subsequent vibration and deformation trends based on the current machining parameters (cutting speed, feed rate, cutting force, etc.) and adjusts the control parameters in advance. For example, if it is predicted that the vibration frequency in the next cutting area will rise to 1500Hz, the output voltage of the piezoelectric actuator will be adjusted to 850V in advance to improve the control response speed.

[0062] Step 6: Processing Completion and Equipment Reset. After the machine tool completes the milling process, the synchronous control unit 72 sends a processing completion signal, and the industrial controller 62 controls the reset of each actuator: the piezoelectric actuator returns to its initial position, the voice coil motor drives the arc-shaped support head 421 away from the blade surface, and the support rod 5111 of the flexible support matrix 51 returns to its initial height; the vacuum chuck 23 releases pressure, the elastic gripper 24 loosens, and the operator removes the processed blade; the cutting chips collected by the chip collection tank 82 are discharged through the chip discharge port, completing the processing flow.

[0063] Tests have verified that the device described in this embodiment can achieve a surface roughness of Ra0.6μm and a dimensional accuracy of IT5 when machining aero-engine blades. The feed rate has been increased from 500mm / min in traditional machining to 700mm / min, machining efficiency has been increased by 40%, rework rate has been reduced from 15% to 2%, and tool life has been increased by 35%. This significantly improves machining quality and efficiency while reducing machining costs.

[0064] Example 2: Active vibration damping and deformation compensation device for spacecraft cabin wall panel processing

[0065] This embodiment focuses on the grinding process of spacecraft cabin walls (wall thickness 1.5-2mm, material 2A12 aluminum alloy, outline dimensions 2000mm×1000mm×1.8mm). It is based on Embodiment 1 with adaptive adjustments, as follows:

[0066] 1. Clamping and positioning module 2: The positioning groove of the flexible clamp seat 21 is machined according to the planar contour of the cabin wall panel. It adopts a multi-point vacuum adsorption structure, and the number of vacuum suction cups 23 is increased to 12, which are evenly distributed at the bottom of the positioning groove. The adsorption force adjustment range is 0-150N, which improves the adsorption stability of large-area wall panels. The elastic pressure claws 24 adopt pneumatic film pressure claws, and the number is increased to 4, which are evenly distributed on the edge of the flexible clamp seat 21. The pressure head is made of soft rubber material to avoid damaging the surface of the wall panel.

[0067] 2. Multi-source sensing monitoring module 3: The number of laser displacement sensors 321 is increased to 4, which are installed around the processing area to realize deformation monitoring of the large-area processing area of ​​the wall panel; the temperature monitoring unit 34 adds 2 contact temperature sensors (using PT100 type), which are attached to the key areas on the back of the wall panel to assist in monitoring thermal deformation and improve the comprehensiveness of temperature monitoring.

[0068] 3. Collaborative vibration damping module 4: The number of voice coil motor follow-up support units 42 is increased to 6, and they are distributed in a 2×3 matrix below the processing area to achieve comprehensive follow-up support and vibration damping for large-area wall panels; the number of piezoelectric actuator groups 41 is increased to 8, and they are evenly distributed at the bottom of the flexible fixture seat 21 to improve the high-frequency vibration damping effect and adapt to the vibration suppression requirements of large-area wall panels.

[0069] 4. Multi-point flexible compensation module 5: The number of flexible support units 511 in the flexible support matrix 51 is increased to 16, which are distributed in a 4×4 matrix, covering the entire non-processed area of ​​the wall panel, realizing uniform compensation for large-area deformation; the path compensation interface 53 is adapted to the machine tool CNC system (Siemens 840D sl type) to realize the correction of complex paths.

[0070] The working process of this embodiment is basically the same as that of embodiment 1. Through multi-source sensing monitoring, coordinated vibration suppression and multi-point compensation, the vibration amplitude of the cabin wall panel processing can be suppressed within ±4μm, the deformation can be reduced to below 8μm, the surface roughness can reach Ra0.5μm, and the dimensional accuracy can reach IT5 level, which meets the high-precision processing requirements of spacecraft cabin wall panels.

[0071] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. An active vibration damping and deformation compensation device for high-precision thin-walled parts machining, characterized in that: It includes a base module (1), a clamping and positioning module (2), a multi-source sensing and monitoring module (3), a cooperative actuation and vibration suppression module (4), a multi-point flexible compensation module (5), an intelligent control module (6), and a machine tool collaborative interface module (7). The multi-source sensing monitoring module (3) is used to synchronously and in real time collect vibration signals and deformation signals during the processing. The intelligent control module (6) generates control commands based on the vibration signal and deformation signal; The coordinated vibration suppression module (4) actively suppresses vibration of the part according to the control command; the multi-point flexible compensation module (5) actively compensates for deformation of the part according to the control command; The machine tool collaborative interface module (7) is used to realize information interaction and action synchronization between the device and the machine tool CNC system.

2. The active vibration damping and deformation compensation device for high-precision thin-walled parts machining according to claim 1, characterized in that: The base module (1) includes a base platform (11), a leveling support (12) at its bottom, and a reinforcing rib on its lower surface; the leveling support (12) is a spiral leveling structure.

3. The active vibration damping and deformation compensation device for high-precision thin-walled parts machining according to claim 1, characterized in that: The clamping and positioning module (2) includes a flexible clamp seat (21), an adaptive positioning pin (22) set in its positioning groove, a vacuum suction cup and an elastic pressure claw; the adaptive positioning pin (22) is provided with a pressure sensor for monitoring positioning pressure.

4. The active vibration damping and deformation compensation device for high-precision thin-walled parts machining according to claim 1, characterized in that: The multi-source sensing monitoring module (3) includes a vibration monitoring unit (31) for monitoring vibration acceleration, a deformation monitoring unit (32) for monitoring part displacement and strain, a cutting force monitoring unit for monitoring cutting force, and a temperature monitoring unit for monitoring the temperature of the machining area.

5. The active vibration damping and deformation compensation device for high-precision thin-walled parts machining according to claim 1, characterized in that: The cooperative vibration suppression module (4) includes a piezoelectric actuator group (41) for suppressing high-frequency vibration and a voice coil motor follower support unit (42) for suppressing low-frequency vibration and providing follower support; the output end of the voice coil motor follower support unit (42) is provided with an arc-shaped support head with a pressure sensor.

6. The active vibration damping and deformation compensation device for high-precision thin-walled parts machining according to claim 1, characterized in that: The multi-point flexible compensation module (5) includes a flexible support matrix (51) composed of multiple independent flexible support units, an electric push rod adjustment unit for adjusting the overall posture of the fixture seat, and a path compensation interface for sending tool path correction commands to the machine tool CNC system; each of the flexible support units includes a support push rod, a pressure sensor for monitoring the support force, and a micro servo motor for driving the support push rod.

7. The active vibration damping and deformation compensation device for high-precision thin-walled parts machining according to claim 1, characterized in that: The intelligent control module (6) includes a data acquisition card, an industrial controller, and an algorithm processing unit integrated therein; the algorithm processing unit includes a signal preprocessing algorithm for data filtering, a vibration and deformation recognition algorithm for feature extraction, a collaborative control algorithm for generating control commands, and a prediction model trained based on historical data.

8. The active vibration damping and deformation compensation device for high-precision thin-walled parts machining according to claim 1, characterized in that: The machine tool collaborative interface module (7) includes an EtherCAT bus communication interface for high-speed data transmission and a synchronization control unit for synchronizing the actions of the synchronization device and the cutting actions of the machine tool.

9. The active vibration damping and deformation compensation device for high-precision thin-walled parts machining according to claim 1, characterized in that: It also includes a protective module, which includes a transparent protective cover surrounding the processing area and a debris collection trough disposed around the base platform (11).

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