Microsphere target five-axis machining method and system based on FTP protocol

Abstract

The application provides a microsphere target five-axis machining method and system based on an FTP protocol, and belongs to the field of thin-wall microsphere target machining. In order to solve the problem that in the machining process of the global surface feature structure of the existing thin-wall microsphere target complex micro component, the compatibility is insufficient, the interaction is poor, the robustness is poor, the control authority is insufficient, and the microstructure machining numerical control program is difficult to be edited and loaded online efficiently, the microstructure machining program code is prepared based on the microsphere target and the geometric features of the microstructure to be machined, communication between the host computer control system and the motion controller is established by the FTP file transfer protocol, the program is loaded to the controller, and then each shaft servo motion is controlled. The application cooperates with high-precision program editing, efficient and stable program loading and servo control, and can provide key process and equipment support for high-precision micro-milling forming of the global surface feature structure of the microsphere target.

Description

Technical Field

[0001] This invention relates to the field of thin-walled microsphere target processing technology, and more specifically, to a five-axis microsphere target processing method and system based on the FTP protocol. Background Technology

[0002] With the rapid development of high-end manufacturing equipment and ultra-precision machining processes, complex micro-components such as sub-millimeter-scale high-precision thin-walled microspheres have attracted widespread attention in aerospace and biomedical fields. Engineering applications require the fabrication of over a hundred multi-scale microstructures across the entire surface of these components, demanding sub-micrometer-level surface accuracy, nanometer-level surface roughness, and high-precision consistency. This typically necessitates ultra-precision five-axis machining equipment, where a dedicated CNC system programs the machining process and loads it onto a controller to control the axis movements and achieve stable removal of the microstructure material, thus meeting the high-precision manufacturing requirements.

[0003] The microsphere target component is a sub-millimeter scale soft and brittle polymer thin-walled spherical shell. The machining of its more than one hundred microstructures on its global surface requires a uniform distribution of better than 80% and a shell thickness uniformity of better than 90%, involving key processes such as point set distribution, trajectory planning, and reversing clamping. During machining, the machining program must be edited online based on the geometric characteristics and engineering requirements of the microsphere target, placing stringent demands on the efficiency and portability of the CNC system's program editing. Current industrial practice often employs offline program editing, relying on third-party programming or post-processing software to write machining code offline, which is then imported into the CNC system in a specific format. This approach suffers from low efficiency, insufficient compatibility, and poor interactivity. Furthermore, traditional program code loading methods often transmit via serial interfaces, resulting in slow transmission speeds and poor robustness. Emerging distributed CNC systems, based on HTTP, P2P, and other file download protocols, use LANs or Ethernet for data transmission. While this improves transmission efficiency and stability, it lacks native file directory management permissions and hinders automated software deployment. Current mainstream program editing and loading methods cannot meet the manufacturing requirements of efficient online editing and stable transmission of machining programs for complex micro-components such as thin-walled microspheres. Therefore, to address the problem of high-precision machining of global surface microstructures for thin-walled microspheres, there is an urgent need to develop a CNC program editing module and loading method based on the FTP protocol to meet the application needs of the engineering field. Summary of the Invention

[0004] The technical problem to be solved by this invention is:

[0005] To address the problems in the current machining process of complex micro-components such as thin-walled microspheres and targets, which suffer from insufficient compatibility, poor interactivity, poor robustness, and insufficient control permissions, making it difficult to efficiently edit and stably load CNC programs for microstructure machining online.

[0006] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0007] This invention provides a five-axis machining method for microsphere targets based on the FTP protocol, comprising the following steps:

[0008] S100. Turn on the ultra-precision five-axis machining equipment and its CNC system, and confirm the hardware connection; turn on the negative pressure to adsorb and clamp the thin-walled microsphere target component onto the fixture; turn on the milling axis conversion switch to clamp the single-edged diamond tool onto the milling axis, and turn on the industrial computer desktop CNC system software.

[0009] S200. Adjust the actual working distance and magnification of the visual monitoring system until the edge contour of the microsphere target is clearly imaged, and obtain an optical image of the microsphere target contour.

[0010] S300. Based on the microsphere target diameter and the number of feature structures processed by image processing, the coordinates of the microstructure point set in the workpiece coordinate system are optimized based on the uniformity iterative optimization algorithm: a spherical crown microstructure difference uniformity evaluation function is constructed, and the gradient descent iterative strategy is used to fine-tune the coordinates of each point along the tangent of the spherical surface until the uniformity evaluation function value converges to below the preset threshold.

[0011] S400. Optimal processing sequence planning for microstructures based on the improved Traveling Salesman Problem (TSP) algorithm: Using the motion cost in the five-axis linkage space as the distance metric between nodes, a heuristic optimization algorithm is used to solve for the processing sequence arrangement with the minimum total path length.

[0012] S500, based on the code editing module and the coordinates of the microstructure processing point set on the global surface of the microsphere target, write the microstructure processing program code;

[0013] After the S600 program is checked and found to be correct, open the controller IDE software, enable and configure the FTP server function, and set the IP address and port; create an FTP connection request pointing to the target directory to establish FTP communication; the host computer CNC system responds to the request and obtains the download address and port, establishing a program code data transmission channel; the CNC system reads the program code into a byte stream and transmits it to the controller;

[0014] The S700 X / Y / Z axis linear motion unit and B / C axis rotary motion unit driver receive input signals from the controller and change the amplitude and phase of the output current, as well as the speed and displacement, to achieve high-precision servo control of the motion axis system.

[0015] Furthermore, the visual monitoring system is connected to the shaft transition element through a four-degree-of-freedom micro-displacement platform. The four-degree-of-freedom micro-displacement platform can be adjusted for linear displacement along the X / Y / Z axes and for rotational angle adjustment along the direction perpendicular to the mounting surface.

[0016] Further, in step S300,

[0017] Define the evaluation function for the microstructure heterogeneity of the spherical cap. :

[0018]

[0019] In the formula, P = {p1, p2, ..., p} N Let} be the set of microstructure center points on the surface of the microsphere target, p i Let be the i-th microstructure center point, N be the total number of microstructure center points; C be any spherical cap region on the sphere; P∩C be the set of microstructure center points located within the spherical cap region C, and |P∩C∣| be the number of microstructure center points within that region; Ω be the set of all spherical cap microstructures on the sphere, A(C) be the area of ​​the spherical cap microstructure, and R be the radius of the microsphere target; the smaller D(P) is, the more uniform the distribution of the point set on the sphere;

[0020] In the gradient descent iterative strategy, during the k-th iteration, for each point... Calculate its relationship with all other points. tangential repulsive force :

[0021]

[0022] Remove the radial component to obtain the pure tangential update direction. :

[0023]

[0024] Update the point coordinates and project them back onto the sphere:

[0025]

[0026] Where η is the learning rate, normalize is the spherical normalization operation, and the iteration continues until... ε is the preset convergence precision.

[0027] Further, in step S400,

[0028] Motion cost is defined as :

[0029]

[0030] Where, ΔL ij Let ΔB be the displacement along the X / Y / Z linear axes. ij ΔC ij The change in the rotation angle of the B / C axis is given by α, β, and γ, which are weighting coefficients.

[0031] In the heuristic optimization algorithm, specifically the genetic algorithm, the objective function is:

[0032]

[0033] Where Ψ represents the processing sequence.

[0034] Further, step S500 includes: 1) closing all buffers and defining the coordinate system and axis system; 2) opening a buffer for the program to be loaded and clearing the existing cache contents; 3) defining the axis system motion interpolation mode and programming mode; 4) setting the axis system motion parameters; and 5) compiling the machining CNC program.

[0035] Furthermore, in step S600, to improve the reliability and efficiency of large-size machining program transmission, an enhancement mechanism is added to the standard FTP protocol:

[0036] Resume interrupted transmission: During the transmission process, the host computer records the offset of the transmitted bytes in real time. If the transmission is interrupted due to network fluctuations, it will resume transmission from the offset point after reconnection, avoiding repeated transmission.

[0037] Multi-threaded block transfer: The program code file is divided into multiple data blocks, and different data blocks are transferred simultaneously by establishing multiple concurrent FTP connections. The controller reassembles the blocks according to their sequence numbers and performs integrity verification after the transfer is completed.

[0038] MD5 Integrity Verification: Before transmission begins, the host computer calculates the MD5 checksum of the source file and transmits it along with the file; after transmission is complete, the controller calculates the MD5 value of the received file and compares it with the checksum from the source. If they do not match, the file is automatically retransmitted.

[0039] Adaptive window congestion control: Monitors network round-trip time (RTT) and packet loss rate, dynamically adjusts the transmission window size, adopts linear growth during the congestion avoidance phase, and employs a slow start strategy during the timeout retransmission phase.

[0040] Furthermore, in step S700, the motion controller adopts an analog control strategy. Based on the program instructions of the host computer control software, it outputs analog signals to control the drivers of each axis motion unit. The drivers change the amplitude and phase of the output current, change the speed and displacement, and realize the servo control of the motion axis.

[0041] A five-axis machining system for microsphere targets based on the FTP protocol is provided. The system has program modules corresponding to the above steps and executes the steps in the above-described five-axis machining method for microsphere targets based on the FTP protocol when running.

[0042] A computer-readable storage medium storing a computer program configured to implement, when invoked by a processor, the steps of a five-axis machining method for a microsphere target based on the FTP protocol.

[0043] Compared with the prior art, the beneficial effects of the present invention are:

[0044] This invention addresses the bottlenecks of existing code editing and transmission methods, such as insufficient compatibility, poor interactivity, poor robustness, and insufficient management permissions, which hinder the efficient online editing and stable loading of microstructure machining programs. It proposes a microsphere target global surface microstructure machining program editing module and loading method based on the FTP protocol. This provides technical support for editing and downloading machining programs for sub-millimeter-level surface feature structures of complex micro-components such as sub-millimeter-scale thin-walled microsphere targets, achieving sub-micrometer-level surface accuracy, nanometer-level surface roughness, and high-precision consistency.

[0045] This invention is based on the FTP file transfer protocol, which provides interactive file transfer operations and supports file upload, download, deletion and renaming operations between the host computer and the control system. It uses interactive access, allowing users to specify the file type and format, and allowing files to have access permissions. It is suitable for the efficient transmission of processing programs for more than 100 feature microstructures on the global surface of sub-millimeter scale thin-walled microsphere target components.

[0046] This invention independently develops a CNC system host computer control software and uses a network library for data transmission. The software includes a program editing module and an image monitoring module, which meet the manufacturing needs such as editing the machining program code and obtaining high-precision image information of the microsphere target diameter, and provide data support for the compilation of microsphere target machining programs.

[0047] This invention relates to an ultra-precision five-axis machining equipment and its CNC system for complex micro-components such as thin-walled microspheres. It is equipped with a high-precision X / Y / Z-axis linear motion unit with a straightness better than 100nm and a positioning accuracy better than 0.4μm, a hydraulic B-axis rotary motion unit with a radial error better than 0.1 μm and a positioning accuracy better than 0.4″, and a gas static pressure C-axis rotary motion unit with radial and axial errors both better than 12nm. Together with high-precision program editing, efficient and stable program loading and servo control, it can provide key process and equipment support for high-precision micro-milling of the global surface feature structure of microspheres.

[0048] This invention, based on Fibonacci spherical sampling, innovatively introduces a uniformity iterative optimization algorithm based on the difference measurement of spherical cap microstructures, improving the uniformity of microstructure point set distribution from 75% to 87%, ensuring consistent global surface machining quality. Simultaneously, it introduces a machining path planning algorithm based on an improved TSP, using five-axis linkage spatial motion cost as a distance metric. After optimization with a genetic algorithm, the tool idle travel is shortened by approximately 38%, significantly improving machining efficiency. Furthermore, it adds enhancement mechanisms to the FTP protocol, such as breakpoint resumption, block concurrency, MD5 checksum, and adaptive congestion control, increasing the program transmission success rate to 99.8%. These systematic innovations at the algorithmic level, in conjunction with high-precision hardware, form a complete technology chain of "point set generation - uniformity optimization - path planning - code generation - reliable transmission - precision servo," solving the long-standing core technical challenges in the machining of global surface microstructures of thin-walled microsphere targets, such as low programming efficiency, poor transmission stability, and suboptimal machining paths.

[0049] This invention has a certain degree of universality. It is not only applicable to the editing and loading of global surface feature structure processing programs for thin-walled microsphere target components, but can also be further extended to the specific practice of editing and transmitting CNC code files when forming multi-process features of macro-micro-nano scale parts and cross-scale feature structures. Attached Figure Description

[0050] Figure 1 This is a framework diagram of a five-axis microsphere target machining system based on the FTP protocol in an embodiment of the present invention;

[0051] Figure 2 This is a structural diagram of the code editing module in an embodiment of the present invention;

[0052] Figure 3 This is a flowchart of a five-axis machining method for microsphere targets based on the FTP protocol in an embodiment of the present invention;

[0053] Figure 4 The appendix diagram shows the microstructure fabrication process in the embodiments of the present invention. Detailed Implementation

[0054] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0055] Specific Implementation Plan 1: Combining Figures 1 to 3 As shown, this invention provides a five-axis machining system for microsphere targets based on the FTP protocol, including a code editing module, a program loading unit based on the FTP protocol, and an axis motion module.

[0056] Combination Figure 2As shown, the code editing module is used for generating the machining point set of the global surface feature structure of the microsphere target, coordinate transformation, program editing, and providing real-time feedback on the program running status. Specifically, based on the geometric characteristics of the microsphere target and the microstructure to be processed, the Fibonacci principle is used to generate the coordinates of the microstructure point set in the workpiece coordinate system, and the coordinates of the microstructure in the machining coordinate system are obtained by the coordinate transformation method. The microstructure machining program is then written using the code editing module.

[0057] The controls for the code editing module include program opening, program saving, program download, loading progress and program path display, and a program editing box;

[0058] The FTP-based program loading unit is used for FTP server configuration, FTP connection request creation, data transmission connection establishment, byte stream code reading, and processing program file transfer. Specifically, the FTP-based program loading unit is connected to the shaft motion module and transmits the program code file to the controller via Ethernet communication. The file transfer progress can be displayed in real time on the code editing module via a progress bar.

[0059] The shaft motion module is based on a controller that controls the driver through analog input and adjusts the output current to achieve high-precision shaft servo control of the shaft motion module.

[0060] The axis motion module includes X / Y / Z axis linear motion units, B / C axis rotary motion units, a milling axis, cutting tools, and fixtures. The thin-walled microsphere target component is suction-attached to the end of the fixture in the C-axis rotary motion unit via negative pressure. The cutting tool is connected to the end of the milling axis via a pneumatic chuck. The X / Z axis linear motion units use Parker I-Force 410 series linear motors with a peak thrust of 2967 N, paired with Heidenhain LIP201R 420 (2 μm pitch) high-precision diffraction grating rulers, and are driven by a TA330 driver. The Y-axis linear motion unit uses a Parker I-Force 310 linear motor with a peak thrust of 600 N, paired with Heidenhain LIP201R 170 (2 μm pitch) high-precision diffraction grating rulers, and is driven by a TA330 driver. The TA330 driver is a Class B push-pull amplifier with linear output, no zero-point dead zone, no crossover distortion, no electromagnetic noise, and a peak current of 18 N / m². A; The linear motion unit has a straightness better than 100 nm and a positioning accuracy better than 0.4 μm; B-axis rotary motion unit uses a hydraulic rotary table manufactured by AMETEKPRECITECH, with a radial error of 0.1 μm, a conical runout of 1 nm / mm, a load capacity of 225 kg, and a positioning accuracy better than 0.4″; C-axis rotary motion unit uses a rotary axis of model ISO 5.5 PG manufactured by PI, driven by an Aerotech Soloist CP20 driver, with radial and axial errors both less than 12 nm.

[0061] It also includes a visual monitoring system composed of dual high-resolution CCD cameras, used to observe the milling process status in the tool-workpiece contact area;

[0062] In summary, based on the geometric features of the thin-walled microsphere target component and the microstructure to be processed, the microstructure processing program code is compiled, and the communication between the host computer control system and the motion controller of the axis motion module is established by the program loading unit based on the FTP protocol, the program is loaded into the controller, and then the servo motion of each axis is controlled.

[0063] Specific Implementation Plan 1: Combining Figures 1 to 3 As shown, this invention provides a five-axis machining method for microsphere targets based on the FTP protocol, comprising the following steps:

[0064] S100. Turn on the ultra-precision five-axis machining equipment and its CNC system, and confirm the hardware connection; turn on the negative pressure to adsorb and clamp the thin-walled microsphere target component onto the fixture; turn on the milling axis conversion switch to clamp the single-edged diamond tool onto the milling axis, and turn on the industrial computer desktop CNC system software.

[0065] Specifically, including,

[0066] Check the connection of the controller and driver of the ultra-precision five-axis machining equipment and the CNC system software enablement. Adjust the pressure of the negative pressure source of the equipment to ensure that the thin-walled microsphere target component is stably adsorbed at the end of the C-axis fixture. Turn on the pneumatic switch of the milling axis. The tool is clamped at the end of the milling axis through the HSK chuck and locked pneumatically. The tool used is a single-flute diamond ball end mill with a radius R of 0.303mm and a tool shank diameter of 6mm. The HSK chuck used holds the tool with a diameter of 6mm, a rotation accuracy better than 0.003mm, and a minimum torque of 10Nm.

[0067] The visual monitoring system is connected to the shaft transition element through a four-degree-of-freedom micro-displacement platform. The four-degree-of-freedom micro-displacement platform can make linear displacement adjustment along the X / Y / Z axes and rotation angle adjustment along the direction perpendicular to the mounting surface (linear displacement adjustable stroke ±12.5mm, fine adjustment accuracy 2μm; rotation angle coarse adjustment stroke 360°, fine adjustment stroke ±5°, fine adjustment accuracy 1°).

[0068] S200. Adjust the actual working distance and magnification of the visual monitoring system until the edge contour of the microsphere target is clearly imaged, and obtain an optical image of the microsphere target contour.

[0069] S300, based on the microsphere target diameter D: 1.000mm and the number of microstructures to be processed on the global surface N: 20, the coordinates N of the microstructure point set in the workpiece coordinate system are obtained using the Fibonacci sequence. w-i (x wi ,y wi ,z wi ,b wi ,c wi As shown in Table 1 below;

[0070] Table 1. Coordinates of the microstructure point set on the surface of the microsphere target in the workpiece coordinate system (N=20)

[0071]

[0072] Based on the microsphere target diameter and the number of feature structures processed obtained through image processing, and relying on the Fibonacci principle, mutually perpendicular X and Y axes are established in the equatorial plane of the microsphere target, and the Z axis is determined based on the right-hand rule to establish the workpiece coordinate system. The sphere is divided into N layers of equal thickness, and the midpoint of each layer is taken as the Z-axis coordinate. The X and Y coordinates are further divided according to the arithmetic sequence of longitude to obtain the coordinate set of microstructure processing points in the workpiece coordinate system.

[0073] The initial point set P0={p1, p2, …p} generated by the Fibonacci principle NAlthough it satisfies a certain degree of uniformity, the distribution uniformity is usually only about 75% due to the influence of spherical discretization error, which is difficult to meet the engineering requirement that the global surface microstructure distribution uniformity of thin-walled microspherical targets is better than 80%. To this end, this invention proposes a uniformity iterative optimization algorithm based on the difference measurement of spherical cap microstructure.

[0074] Specifically, including,

[0075] Define the evaluation function for the microstructure heterogeneity of the spherical cap. :

[0076]

[0077] In the formula, P = {p1, p2, ..., p} N Let} be the set of microstructure center points on the surface of the microsphere target, p i Let P be the center point of the i-th microstructure, |P|=N be the total number of microstructure center points; C be any spherical cap region on the sphere, Ω be the set of all spherical cap microstructures on the sphere; P∩C be the set of microstructure center points located within the spherical cap region C, |P∩C∣ be the number of microstructure center points within that region; Ω be the set of all spherical cap microstructures on the sphere, A(C) be the area of ​​the spherical cap microstructure, and R be the radius of the microsphere target; the smaller D(P) is, the more uniform the distribution of the point set on the sphere;

[0078] The iterative optimization process is as follows:

[0079] In the kth iteration, for each point Calculate its relationship with all other points. tangential repulsive force :

[0080]

[0081] Remove the radial component to obtain the pure tangential update direction. :

[0082]

[0083] Update the point coordinates and project them back onto the sphere:

[0084]

[0085] Where η is the learning rate (0.01 in this embodiment), normalize(x) = x / ||x||;

[0086] Iterate to , ε Take 10 -4 To achieve the preset convergence accuracy, after optimization, the uniformity of the point set distribution was improved from the initial 75% to 87%, meeting engineering requirements.

[0087] S400. Based on the coordinate transformation method, transform the coordinate set of points in the workpiece coordinate system to the machining coordinate system N. m-i (x mi ,y mi ,z mi ,b mi ,c mi As shown in Table 2 below,

[0088] Table 2. Coordinates of microstructures on the surface of the microsphere target in the machining coordinate system (N=20)

[0089]

[0090] Based on the improved TSP optimal machining sequence planning, after obtaining N microstructure machining points in the machining coordinate system in step S300, the machining sequence directly affects the tool idle travel time and machining efficiency; this invention models the machining sequence optimization as a traveling salesman problem (TSP) and introduces the cost of five-axis linkage motion as the distance between nodes;

[0091] Define the motion cost between any two points i and j. :

[0092]

[0093] in, For linear axial displacement, Let i be the x, y, and z coordinates of point i. Let j be the x, y, and z coordinates of point j; ΔB ij =|b i - b j |,ΔC ij =|c i - c j | represents the angle difference of the rotation axis. Let i be the coordinates of point i along the B-axis and C-axis. Let j be the coordinates of the B-axis and C-axis; weighting coefficients α=1, β=0.5, γ=0.5, set according to the dynamic response characteristics of each axis;

[0094] The objective function is to minimize the total processing path length.

[0095]

[0096] Wherein, Ψ represents the processing sequence;

[0097] The solution is obtained using an improved genetic algorithm:

[0098] Encoding method: Integer permutation encoding is used, with each individual representing a processing order;

[0099] Initial population: 200 individuals are randomly generated;

[0100] Fitness function:

[0101] Selection operator: Tournament selection, tournament size is 3;

[0102] Crossover operator: Sequential crossover (OX), crossover probability 0.8;

[0103] Mutation operator: Exchange mutation, mutation probability 0.05;

[0104] Termination condition: No improvement in optimal fitness after 200 iterations or 50 consecutive iterations;

[0105] After the above algorithm optimization, the tool idle travel path is shortened by about 38% compared with the original sequence, which significantly improves the machining efficiency. The optimized machining sequence Ψ is used as the basis for subsequent program writing, and the code editing module outputs the machining instructions of each microstructure in sequence according to this order.

[0106] Using the S500 code editing module and the coordinates of N=20 microstructure machining points on the global surface of a D1.000mm microsphere target, write microstructure machining program code, including: 1) closing all buffers and defining the coordinate system and axis system; 2) opening a buffer for the program to be loaded and clearing the existing buffer contents; 3) defining the axis system motion interpolation mode and programming mode; 4) setting the axis system motion parameters; 5) compiling the machining CNC program;

[0107] Meanwhile, clicking the "Open Program Control" opens the locally compiled program code, which can be further edited in the program editing box; clicking the "Save Program Control" completes the program code editing; the program path text box displays the local save path of the program.

[0108] The first 5 microstructure fabrication procedures are as follows: Figure 4 As shown;

[0109] After the S600 program is checked and found to be correct, open the controller IDE software, enable and configure the FTP server function, and set the IP address and port; click "Save Program" in the code editing module to create an FTP connection request pointing to the target directory to establish FTP communication; the host computer CNC system responds to the request and obtains the download address and port, establishing a program code data transmission channel; further click the program download control, and the CNC system reads the program code as a byte stream and transmits it to the controller;

[0110] FTP is a protocol for file transfer between ports, which allows users to upload and download files between the local machine and the host. It supports the following two transfer modes: (1) active mode, where the controller actively connects to the host computer control terminal; (2) passive mode, where the host computer connects to the controller.

[0111] The FTP-based program loading unit is used to load the micro-sphere target global surface feature micro-structure machining program code, compiled in the host computer control software of the five-axis machining equipment, into the axis motion module. The implementation steps are as follows: ① Parameter configuration: Enable and configure the FTP server function through the system controller IDE software, setting a fixed IP address, port, and dedicated file storage directory; reference the data transmission network library in the host computer control software application; ② Communication request: Create an FTP connection request pointing to the target directory by clicking the program save control in the program editor to establish FTP communication; ③ Communication establishment: The host computer CNC system responds to the FTP file synchronization command request and obtains the download address and port of the server in the controller, establishing a program code data transmission channel; ④ Code Conversion and Transmission: The program code within the program editing box is read as a byte stream using the program download control in the code editing module. A request stream is obtained via FTP connection, and the file byte stream is written to this network stream. The microstructure machining code data then begins transmission to the controller, achieving efficient and stable transmission of the program code file. The byte stream is a common data representation and processing method in computers. During microstructure machining program download, the program code is read and converted into a continuous, unstructured sequence of raw bytes (byte stream object), preparing for data transmission. The network stream is the sequence of data bytes flowing during network file transmission, representing the channel and carrier for code data transmission between the CNC system's host computer and the controller. The request stream is a write port pointing to the FTP server network stream, serving as the programming interface for the machining program in the host computer to actively initiate data transmission. It injects local byte stream data into the network stream to initiate the actual data transmission to the controller. The device motion controller is a Power UMAC with a 1GHz operating frequency, 64-bit (double-precision) floating-point computing, and built-in USB 2.0, Ethernet 100 Mbps, and 1Gbps interfaces, meeting the high-precision control requirements of microstructure machining.

[0112] To improve the reliability and efficiency of transmitting large-size machining programs, this method adds an enhancement mechanism to the standard FTP protocol:

[0113] (1) Resume transmission from interruption: During the transmission process, the host computer records the offset of the transmitted bytes in real time. If the transmission is interrupted due to network fluctuations, the transmission will resume from the offset after reconnection to avoid repeated transmission.

[0114] (2) Multi-threaded block transmission: The program code file is divided into multiple data blocks of 64KB each. Multiple FTP concurrent connections are established to transmit different data blocks simultaneously. The controller reassembles the blocks according to their sequence numbers and performs integrity verification after transmission is completed.

[0115] (3) MD5 integrity check: Before the transmission starts, the host computer calculates the MD5 check value of the source file and transmits it along with the file; after the transmission is completed, the controller calculates the MD5 value of the received file and compares it with the check value of the source. If they are inconsistent, the transmission is automatically retransmitted.

[0116] (4) Adaptive window congestion control: Monitor network round-trip time (RTT) and packet loss rate, dynamically adjust the transmission window size, adopt linear growth in the congestion avoidance phase, and adopt a slow start strategy in the timeout retransmission phase;

[0117] Experiments show that for 5MB-level processing program files, the above-mentioned enhancement mechanism reduces the transmission time from 5-8 minutes of traditional serial port transmission to less than 25 seconds, and increases the transmission success rate from 85% to 99.8%.

[0118] The S700 X / Y / Z axis linear motion unit and B / C axis rotary motion unit driver receive input signals from the controller and change the amplitude and phase of the output current, as well as the speed and displacement, to achieve high-precision servo control of the motion axis system.

[0119] The motion controller adopts an analog control strategy. Based on the program instructions of the host computer control software, it outputs analog signals to control the drivers of each axis motion unit. The drivers change the amplitude and phase of the output current, change parameters such as speed and displacement, and realize high-precision servo control of the motion axis.

[0120] The other combinations and connections in this implementation scheme are the same as in Specific Implementation Scheme 1.

[0121] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A five-axis machining method for microsphere targets based on the FTP protocol, characterized in that: Includes the following steps, S100. Turn on the ultra-precision five-axis machining equipment and its CNC system, and confirm the hardware connection; turn on the negative pressure to adsorb and clamp the thin-walled microsphere target component onto the fixture; Turn on the milling axis selector switch, clamp the single-edged diamond tool onto the milling axis, and open the CNC system software on the industrial computer desktop; S200. Adjust the actual working distance and magnification of the visual monitoring system until the edge contour of the microsphere target is clearly imaged, and obtain an optical image of the microsphere target contour. S300. Based on the microsphere target diameter and the number of feature structures processed by image processing, the coordinates of the microstructure point set in the workpiece coordinate system are optimized based on the uniformity iterative optimization algorithm: a spherical crown microstructure difference uniformity evaluation function is constructed, and the gradient descent iterative strategy is used to fine-tune the coordinates of each point along the tangent of the spherical surface until the uniformity evaluation function value converges to below the preset threshold. S400. Optimal processing sequence planning for microstructures based on the improved Traveling Salesman Problem (TSP) algorithm: Using the motion cost in the five-axis linkage space as the distance metric between nodes, a heuristic optimization algorithm is used to solve for the processing sequence arrangement with the minimum total path length. S500, based on the code editing module and the coordinates of the microstructure processing point set on the global surface of the microsphere target, write the microstructure processing program code; After verifying that the S600 program is error-free, open the controller IDE software, enable and configure the FTP server function, and set the IP address and port; create an FTP connection request pointing to the target directory to establish FTP communication; The host computer CNC system responds to the request and obtains the download address and port, establishing a program code data transmission channel; The CNC system reads the program code into a byte stream and transmits it to the controller; The S700 X / Y / Z axis linear motion unit and B / C axis rotary motion unit driver receive input signals from the controller and change the amplitude and phase of the output current, as well as the speed and displacement, to achieve high-precision servo control of the motion axis system.

2. The five-axis machining method for microsphere targets based on the FTP protocol according to claim 1, characterized in that: The visual monitoring system is connected to the shaft transition element through a four-degree-of-freedom micro-displacement platform. The four-degree-of-freedom micro-displacement platform can be adjusted for linear displacement along the X / Y / Z axes and for rotational angle adjustment along the direction perpendicular to the mounting surface.

3. The five-axis machining method for microsphere targets based on the FTP protocol according to claim 2, characterized in that: In step S300, Define the evaluation function for the microstructure heterogeneity of the spherical cap. : In the formula, P = {p1, p2, ..., p} N Let} be the set of microstructure center points on the surface of the microsphere target, p i Let be the i-th microstructure center point, N be the total number of microstructure center points; C be any spherical cap region on the sphere; P∩C be the set of microstructure center points located within the spherical cap region C, and |P∩C∣| be the number of microstructure center points within that region; Ω be the set of all spherical cap microstructures on the sphere, A(C) be the area of ​​the spherical cap microstructure, and R be the radius of the microsphere target; the smaller D(P) is, the more uniform the distribution of the point set on the sphere; In the gradient descent iterative strategy, during the k-th iteration, for each point... Calculate its relationship with all other points. tangential repulsive force : Remove the radial component to obtain the pure tangential update direction. : Update the point coordinates and project them back onto the sphere: Where η is the learning rate, normalize is the spherical normalization operation, and the iteration continues until... ε is the preset convergence precision.

4. The five-axis machining method for microsphere targets based on the FTP protocol according to claim 3, characterized in that: In step S400, Motion cost is defined as : Where, ΔL ij Let ΔB be the displacement along the X / Y / Z linear axes. ij ΔC ij The change in the rotation angle of the B / C axis is given by α, β, and γ, which are weighting coefficients. In the heuristic optimization algorithm, specifically the genetic algorithm, the objective function is: Where Ψ represents the processing sequence.

5. The five-axis machining method for microsphere targets based on the FTP protocol according to claim 4, characterized in that: Step S500 includes: 1) closing all buffers and defining the coordinate system and axis system; 2) allocating a buffer for the program to be loaded and clearing the existing cache contents; 3) Define the axis motion interpolation mode and programming mode; 4) Set the axis motion parameters; 5) Compile the machining CNC program.

6. The five-axis machining method for microsphere targets based on the FTP protocol according to claim 5, characterized in that: In step S600, to improve the reliability and efficiency of large-size machining program transmission, an enhanced mechanism is added to the standard FTP protocol: Resume interrupted transmission: During the transmission process, the host computer records the offset of the transmitted bytes in real time. If the transmission is interrupted due to network fluctuations, it will resume transmission from the offset point after reconnection, avoiding repeated transmission. Multi-threaded block transfer: The program code file is divided into multiple data blocks, and different data blocks are transferred simultaneously by establishing multiple concurrent FTP connections. The controller reassembles the blocks according to their sequence numbers and performs integrity verification after the transfer is completed. MD5 Integrity Verification: Before transmission begins, the host computer calculates the MD5 checksum of the source file and transmits it along with the file; after transmission is complete, the controller calculates the MD5 value of the received file and compares it with the checksum from the source. If they do not match, the file is automatically retransmitted. Adaptive window congestion control: Monitors network round-trip time (RTT) and packet loss rate, dynamically adjusts the transmission window size, adopts linear growth during the congestion avoidance phase, and employs a slow start strategy during the timeout retransmission phase.

7. The five-axis machining method for microsphere targets based on the FTP protocol according to claim 6, characterized in that: In step S700, the motion controller adopts an analog control strategy. Based on the program instructions of the host computer control software, it outputs analog signals to control the drivers of each axis motion unit. The drivers change the amplitude and phase of the output current, change the speed and displacement, and realize the servo control of the motion axis.

8. A five-axis machining system for microsphere targets based on the FTP protocol, characterized in that: The system has a program module corresponding to the steps of any one of the claims 1-7 above, and executes the steps in the above-described five-axis machining method for microsphere targets based on the FTP protocol when running.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program configured to, when invoked by a processor, implement the steps of the five-axis machining method for microsphere targets based on the FTP protocol as described in any one of claims 1-7.

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