Laser ablation and milling collaborative processing system and method for hard and brittle materials

Abstract

The invention discloses a laser ablation and milling collaborative processing system and method for hard and brittle materials. The system comprises a machine tool milling system, a laser ablation system and a cooperative control device, the laser ablation system carries an ablation mechanism through a six-degree-of-freedom mechanical arm, the cooperative control device generates cooperative data based on a machining program, and cooperative machining with advanced laser ablation and lagged milling is achieved. According to the method, the milling lag time interval is calculated through the Newton's law of cooling, a laser ablation track is generated by combining G code analysis, a non-ablation section is added, and the machining safety and precision are ensured in cooperation with a visual obstacle avoidance module, a laser focusing adjustment module and other modules. According to the system and the method, the problems of cutter abrasion, low efficiency, difficulty in thermal damage control and the like in hard and brittle material processing are solved, high-efficiency, high-precision and low-damage processing is realized, the complex molded surface processing requirement is met, and the laser advanced ablation time is quantified to balance the processing efficiency and precision.

Description

Technical Field

[0001] The present invention relates to the technical field of hard and brittle material processing, and in particular to a laser ablation and milling collaborative processing system and method for hard and brittle materials. Background Art

[0002] With the development of aviation manufacturing technology, hard and brittle materials represented by reaction-sintered silicon carbide and ceramic-based composites have become the core materials for high-performance hot-end structural parts of aircraft due to their high temperature resistance, high specific strength, light weight and high damage tolerance. The application of such materials requires four key links: material forming, mechanical processing, component assembly and whole machine assembly, among which mechanical processing is the core step that determines the final performance of the component. However, the intrinsic characteristics of hard and brittle materials such as high hardness, high brittleness, anisotropy and heterogeneity bring severe challenges to the processing process: severe tool wear and chipping, high processing loads, easy occurrence of edge chipping and chatter mark defects, and the risk of material damage is significantly increased due to the influence of fiber direction and weak interface. Traditional solutions ensure processing quality by reducing material removal rate, but the processing efficiency is low and cannot meet the aviation field's demand for mass production of complex structural parts.

[0003] In response to the above problems, laser-assisted processing technology has become a research hotspot in recent years. For example, laser-assisted grinding, turning, milling and other technologies reduce the hardness of materials through the laser thermal softening effect, thereby improving the processing quality. However, the existing technology still has significant limitations: on the one hand, the thermal softening effect has limited effect on high-temperature resistant materials, and the melting, oxidation and resolidification of the material surface during high-energy laser ablation will cause performance changes, and the degree of damage needs to be precisely controlled; on the other hand, traditional laser-assisted processing focuses more on the optimization of a single process and lacks a multi-process coordination mechanism. For example, the movable ultrafast laser processing robot equipment proposed in patent CN112060103B, although it realizes laser drilling of large-size workpieces, is only suitable for simple hole processing and cannot meet the needs of high-precision milling; the laser ultrasonic dual-assisted milling device disclosed in patent CN215941632U, although it combines laser and ultrasonic technology, has not established a multi-field collaborative processing method, and it is difficult to cope with the precision processing of complex surfaces.

[0004] Furthermore, while the combination of ultrafast lasers and five-axis linkage technology has achieved breakthroughs in micron-level machining accuracy, issues such as the lack of real-time performance of dynamic coupling algorithms and imperfect subsurface crack suppression mechanisms remain to be addressed. For example, while femtosecond laser machining can reduce surface damage, its nonlinear energy absorption mechanism remains unclear, making it difficult to ensure consistent machining quality for large-scale applications. While existing research has proposed partial ablation-milling strategies to improve surface quality, a quantitative relationship between laser advance ablation time and material removal rate has not been established, making it difficult to achieve a balance between machining efficiency and precision. Summary of the Invention

[0005] The present invention aims to address the shortcomings of the aforementioned prior art and achieve efficient, high-precision, and low-damage machining of hard and brittle materials. It proposes a system and method for collaborative laser ablation and milling of hard and brittle materials, ensuring machining accuracy and meeting the demands of machining complex surfaces. Furthermore, the system calculates the minimum laser advance ablation time, thereby ensuring efficient machining of hard and brittle composite materials.

[0006] This application specifically achieves the above objectives through the following technical solutions: A laser ablation and milling collaborative processing system for hard and brittle materials is characterized by comprising a machine tool milling system, a laser ablation system and a collaborative control device; the machine tool milling system comprises a machine tool numerical control mechanism, a machine tool main mechanism and a machine tool spindle unit; the laser ablation system comprises a six-degree-of-freedom robotic arm and a laser ablation mechanism; the collaborative control device comprises a central control unit, a robotic arm control module and a laser ablation control module.

[0007] The central control unit establishes physical communication connections with the machine tool CNC mechanism, laser ablation control module and robotic arm control module respectively, and is used to generate ablation end collaborative data and milling end collaborative data based on the hard and brittle material workpiece processing program, and sends drive collaborative instructions and ablation collaborative instructions to the robotic arm control module and laser ablation control module respectively according to the ablation end collaborative data, and sends milling collaborative instructions to the machine tool CNC mechanism according to the milling end collaborative data.

[0008] The robotic arm control module establishes a physical control connection with the six-degree-of-freedom robotic arm, and is used to parse the drive coordination instructions into drive control signals for the six-degree-of-freedom robotic arm; the six-degree-of-freedom robotic arm is installed at the front end of the workbench of the machine tool main body mechanism, and is used to execute each joint action according to the drive control signals issued by the robotic arm control module.

[0009] The laser ablation control module establishes a physical control connection with the laser ablation mechanism, and is used to parse the ablation coordination instruction into a drive signal for the laser ablation mechanism; the laser ablation mechanism is mounted on the execution end of the six-degree-of-freedom robotic arm, and is used to perform laser ablation processing on hard and brittle material workpieces according to the specified trajectory and speed based on the drive signal issued by the laser ablation control module and the movements of each joint of the six-degree-of-freedom robotic arm.

[0010] The machine tool spindle unit is mounted on the main body of the machine tool, and a milling tool assembly for milling hard and brittle material workpieces is installed on the machine tool spindle unit; the machine tool CNC mechanism and the machine tool spindle unit are physically controlled and connected through a servo control circuit, which is used to control the movement of the machine tool spindle unit according to the milling coordination instruction, so that the milling tool assembly performs milling processing on the hard and brittle material workpiece according to the specified trajectory and speed, which lags behind the laser ablation processing.

[0011] Preferably, the laser ablation system also includes a visual obstacle avoidance unit, and the visual obstacle avoidance unit includes a camera device and an image posture recognition unit; the camera device is physically connected to the image posture recognition unit for real-time acquisition of image data of the machine tool spindle unit and the hard and brittle material workpiece, and the image data is transmitted to the image posture recognition unit; the image posture recognition unit is physically connected to the central control unit for recognizing the real-time dynamic posture information of the machine tool spindle unit and the hard and brittle material workpiece through image data, and transmitting the real-time dynamic posture information to the central control unit, so that the central control unit controls the six-degree-of-freedom robotic arm through the robotic arm control module to avoid the machine tool spindle unit and the hard and brittle material workpiece.

[0012] Preferably, the laser ablation mechanism includes a laser processing head and a laser generator; the laser generator is connected to the laser ablation control module and is used to emit a laser beam according to the drive signal emitted by the laser ablation control module; the laser processing head is connected to the laser generator and is used to focus the laser beam emitted by the laser generator on a workpiece of hard and brittle material.

[0013] Preferably, the collaborative control device also includes a laser focus adjustment unit and a laser rangefinder; the laser rangefinder is mounted on a six-degree-of-freedom robotic arm and establishes a physical communication connection with the laser focus adjustment unit, and is used to measure the real-time distance between the laser processing head and the hard and brittle material workpiece according to the projection of the laser beam emitted by the laser processing head on the surface of the hard and brittle material workpiece, and transmit the real-time distance to the laser focus adjustment unit; the laser focus adjustment unit establishes a physical communication connection with the robotic arm control module, and is used to obtain a distance adjustment signal according to the real-time distance between the laser processing head and the hard and brittle material workpiece, and transmit the distance adjustment signal to the robotic arm control module, and the six-degree-of-freedom robotic arm is controlled by the robotic arm control module to adjust the distance between the laser processing head and the hard and brittle material workpiece, so that the laser beam emitted by the laser processing head is always focused on the surface of the hard and brittle material workpiece.

[0014] Preferably, the laser ablation system further comprises a freeze dryer, and the freeze dryer establishes a physical control connection with the central control unit to provide a dry gas source for the laser generator.

[0015] Preferably, a power distribution cabinet is also included, and the power distribution cabinet is connected to the laser ablation system and the collaborative control device for power supply respectively.

[0016] A method for collaborative laser ablation and milling processing of hard and brittle materials, specifically employing the aforementioned collaborative laser ablation and milling processing system to implement the following processing control steps: The laser ablation and milling collaborative processing system is started and initialized; The central control unit obtains a machining program for a hard and brittle material workpiece, and generates ablation-end collaborative data and milling-end collaborative data based on the machining program for the hard and brittle material workpiece; The central control unit sends driving coordination instructions and ablation coordination instructions to the robot arm control module and the laser ablation control module respectively according to the ablation end coordination data; The robotic arm control module interprets the drive coordination instructions into drive control signals for the six-degree-of-freedom robotic arm, and the laser ablation control module interprets the ablation coordination instructions into drive control signals for the laser ablation mechanism, enabling the laser ablation mechanism to cooperate with the six-degree-of-freedom robotic arm to perform laser ablation processing on hard and brittle material workpieces according to the specified trajectory and speed; The central control unit sends milling coordination instructions to the machine tool CNC mechanism based on the milling end coordination data. The machine tool CNC mechanism runs the hard and brittle material workpiece processing program according to the milling coordination instructions. By controlling the movement of the machine tool spindle unit, the milling tool assembly performs milling processing on the hard and brittle material workpiece according to the specified trajectory and speed, which lags behind the laser ablation processing.

[0017] Preferably, the method for the central control unit to obtain the processing program of the hard and brittle material workpiece includes active acquisition and passive acquisition. The active acquisition is: the central control unit sends a processing program reading instruction to the machine tool numerical control mechanism based on the physical connection established with the machine tool numerical control mechanism through the industrial communication interface; the machine tool numerical control mechanism responds to the instruction and transmits the workpiece processing program to the central control unit in binary or text format. The passive acquisition is: the machine tool numerical control mechanism directly transmits the workpiece processing program to the central control unit in binary or text format based on the physical connection established with the central control unit through the industrial communication interface. After receiving the workpiece processing program, the central control unit performs an integrity check on the workpiece processing program; if the check passes, it enters the next parsing process; if the check fails, it sends error feedback to the machine tool numerical control mechanism.

[0018] Preferably, the process of generating the milling end collaborative data based on the hard and brittle material workpiece processing program includes generating the lag time interval of the milling process relative to the laser ablation process. , that is: Based on Newton's law of cooling, we get formula 1 ;in is the minimum hysteresis time interval, is the mass of the current ablation area of the hard and brittle material workpiece, is the specific heat capacity of the hard and brittle material workpiece, is the convective heat transfer coefficient, is the surface area of the current ablation region of the hard and brittle material workpiece; is the average temperature of the current ablation area, The maximum temperature at which milling can be performed; The current ablation area of the hard and brittle material workpiece is set to be a length, width and height of 、 、 For a rectangular parallelepiped, we have 、 , Represents the density of hard and brittle material workpiece; thus, formula 1 is converted into , calculate the minimum lag time interval ,make .

[0019] Preferably, the process of generating ablation end collaborative data based on the hard and brittle material workpiece processing program includes generating a laser ablation processing trajectory, and the generation of the laser ablation processing trajectory includes the following steps: the central control unit calls the G code parser, scans the workpiece processing program line by line, identifies the instructions related to milling processing, filters non-trajectory instructions, and only retains the trajectory instructions related to the movement of the milling tool assembly. The trajectory instructions are interpolated, and then the discrete trajectory instruction segments are converted into a continuous trajectory point sequence to form the basic data structure of the workpiece milling processing operation trajectory. After the central control unit smoothes the basic data structure of the milling processing operation trajectory, it converts the trajectory coordinate data from the machine tool coordinate system to the reference coordinate system of the laser ablation system to generate a basic ablation trajectory for laser ablation. A non-ablation segment trajectory is added to the end of the basic ablation trajectory to finally generate a laser ablation processing trajectory.

[0020] Preferably, adding a non-ablation segment track at the end of the basic ablation track includes: calculating the minimum distance between the ablation area and the milled area at the same time, that is, ,in Indicates the milling feed rate; considering the milling tool component diameter Under the condition of ,Right now Based on the coordinates of the end point of the basic ablation trajectory, the vector is extended along the ablation motion direction, and the extension length is .

[0021] Preferably, in the process of generating ablation end collaborative data based on the hard and brittle material workpiece processing program, it also includes generating trajectory segmentation marks, which are used as the basis for the laser ablation control module to control the operation of the laser ablation mechanism; the trajectory segmentation marks include traversing the laser ablation processing trajectory point set, marking the points in the basic ablation trajectory as "ablation task segments", and marking the points in the non-ablation segment trajectory as "non-ablation segments".

[0022] Compared with the problems of severe tool wear, low processing efficiency, lack of multi-process coordination mechanism, and insufficient thermal damage control in traditional hard and brittle material processing technology in the background art, the "laser ablation and milling coordinated processing system and method for hard and brittle materials" proposed in this invention brings beneficial technical effects: 1. Multi-process collaboration improves processing efficiency and precision Time coordination between laser ablation and milling: laser ablation is advanced processing, while milling is delayed. The lag time interval is calculated by Newton's cooling law to ensure that the ablation area is cooled to a safe temperature, thus avoiding tool wear and workpiece cracking caused by high temperature. Breaking through the limitations of traditional single process, by quantifying the synergistic relationship (such as The correlation between the thermal and physical properties of the material can improve the material removal efficiency while ensuring the processing quality.

[0023] Trajectory Planning and Dynamic Obstacle Avoidance: Laser ablation trajectories are generated based on G-code analysis, and conflicts with milling trajectories are avoided through a combination of a "basic ablation trajectory and non-ablation segment extension." A visual obstacle avoidance unit identifies the machine tool spindle and workpiece positions in real time, dynamically adjusting the robotic arm's path. This addresses the existing issue of traditional laser-assisted machining, which suffers from a single trajectory and is incapable of processing complex surfaces, enabling precise machining of complex surfaces.

[0024] 2. Thermal Damage Control and Processing Stability Optimization Dynamic laser focus adjustment: A laser rangefinder measures the distance between the processing head and the workpiece in real time. A focus adjustment unit controls the height of the robotic arm to ensure the laser remains focused on the workpiece surface, avoiding uneven energy density caused by distance fluctuations. This improves existing technologies, such as the unclear mechanism of nonlinear energy absorption in ultrafast laser processing and poor processing quality consistency, and enhances surface processing quality.

[0025] Cooling and air source guarantee: The refrigerated dryer provides dry air source for the laser generator to prevent damage to optical components caused by moisture; the power distribution cabinet provides unified power supply to ensure system stability.

[0026] 3. System Integration and Intelligent Control The multi-module linkage of the collaborative control device: The central control unit uniformly generates collaborative data for the ablation and milling ends. Through the robotic arm control module and the laser ablation control module, multiple actuators are precisely driven, supporting active and passive acquisition and integrity verification of machining programs. This addresses the existing problem of "traditional laser-assisted machining lacking a multi-process collaborative mechanism" by enabling dynamic matching of process parameters through integrated control.

[0027] Quantitative design based on physical models: Use Newton's cooling law to establish a lag time calculation model, simplify the ablation area into a cuboid, and derive the time by combining parameters such as material density and specific heat capacity. Minimum value, to achieve a quantitative balance between processing efficiency and thermal damage. Different from the existing technology that "has not established a quantitative relationship between laser advance ablation time and material removal rate", the present invention improves process controllability through physical modeling.

[0028] 4. Enhanced adaptability and security Flexible six-degree-of-freedom robotic arm movement: Equipped with a laser ablation mechanism, the arm adapts to complex trajectories through six-degree-of-freedom joint motion and uses visual obstacle avoidance to prevent collisions with the machine tool spindle, making it suitable for machining large workpieces. This overcomes the existing issue of "lack of real-time dynamic coupling algorithms in five-axis linkage technology" and improves motion accuracy and environmental adaptability.

[0029] Trajectory Segmentation and Laser Output Control: The laser ablation trajectory is marked as "ablation task segments" and "non-ablation segments." Laser output is precisely controlled based on these segmentation markings, reducing ineffective ablation and energy waste. Compared to existing technologies that struggle with controlling the extent of laser ablation damage, this invention achieves precise control of the processing area through trajectory segmentation. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Schematic diagram of the spatial layout structure of the laser ablation and milling collaborative processing system; Figure 2 This is a schematic diagram of the structure layout and installation of the laser ablation system; Figure 3 Schematic diagram of the trajectory relationship between laser ablation and milling; Figure 4 Schematic diagram of the laser focusing trajectory in a single ablation area; Figure 5 This is the electrical control schematic diagram of the laser ablation and milling collaborative processing system.

[0031] 1. Machine tool main structure; 1.1. Workbench; 2. Machine tool spindle unit; 3. Cooperative control device; 4. Six-degree-of-freedom robotic arm; 5. Camera device; 6. Laser processing head; 7. Laser generator; 8. Laser rangefinder; 9. Power distribution cabinet; 10. Refrigerated dryer; 11. Cable; 12. Workpiece made of hard and brittle materials; 13. Basic ablation trajectory; 14. Starting position of laser ablation processing trajectory; 15. End position of laser ablation processing trajectory; 16. Laser focusing trajectory; 17. Area to be processed; 18. Starting position of milling trajectory; 19. End position of milling trajectory; 20. Ablation area. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the drawings in the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0033] Therefore, the following detailed description of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0034] Example 1 This embodiment discloses a system and method for collaborative processing of hard and brittle materials by laser ablation and milling (hereinafter referred to as "collaborative processing system" and "collaborative processing method"), as a preferred embodiment of the present invention. Figure 1 and Figure 5 As shown, the collaborative processing system includes a machine tool milling system, a laser ablation system, and a collaborative control device 3. The machine tool milling system includes a machine tool CNC mechanism, a machine tool main mechanism 1, and a machine tool spindle unit 2; the laser ablation system includes a six-degree-of-freedom robotic arm 4 and a laser ablation mechanism; and the collaborative control device 3 includes a central control unit, a robotic arm control module, and a laser ablation control module.

[0035] The central control unit establishes physical communication connections (such as through cable connections) with the machine tool CNC mechanism, the laser ablation control module and the robotic arm control module respectively, and is used to generate ablation end coordination data and milling end coordination data based on the processing program of the hard and brittle material workpiece 12, and sends drive coordination instructions and ablation coordination instructions to the robotic arm control module and the laser ablation control module respectively according to the ablation end coordination data, and sends milling coordination instructions to the machine tool CNC mechanism according to the milling end coordination data.

[0036] The robotic arm control module establishes a physical control connection with the six-degree-of-freedom robotic arm 4, which is used to parse the drive coordination instructions into drive control signals for the six-degree-of-freedom robotic arm 4; the six-degree-of-freedom robotic arm 4 is installed at the front end of the workbench 1.1 of the machine tool main body mechanism 1, and is used to execute each joint action according to the drive control signals issued by the robotic arm control module.

[0037] The laser ablation control module establishes a physical control connection with the laser ablation mechanism to resolve the ablation coordination instruction into a drive control signal for the laser ablation mechanism; Figure 2 As shown, the laser ablation mechanism is mounted on the execution end of the six-degree-of-freedom robot arm 4, and is used to perform laser ablation processing on the hard and brittle material workpiece 12 according to the specified trajectory and speed based on the drive signal sent by the laser ablation control module and the movements of each joint of the six-degree-of-freedom robot arm 4.

[0038] The machine tool spindle unit 2 is mounted on the machine tool main body mechanism 1, and a milling tool assembly for milling a workpiece 12 made of hard and brittle material is installed on the machine tool spindle unit 2; the machine tool CNC mechanism and the machine tool spindle unit 2 are physically controlled and connected through a servo control circuit, which is used to control the movement of the machine tool spindle unit 2 according to the milling coordination instruction, so that the milling tool assembly performs milling processing on the hard and brittle material workpiece 12 according to the specified trajectory and speed, which lags behind the laser ablation processing.

[0039] Based on the above collaborative processing system, the collaborative processing method of this technical solution includes the following steps: Step 1: Start and initialize the collaborative processing system.

[0040] The central control unit of the collaborative control device 3 establishes a physical communication connection with the machine tool numerical control mechanism through an industrial communication interface (such as EtherCAT, Modbus, OPCUA or TCP / IP) to ensure smooth data transmission channels. Taking OPCUA as an example, it is based on a service-client model and relies on the discovery service (DiscoveryService) defined in the OPCUA protocol. Through this service, the central control unit can automatically identify and connect to the address space exposed by the machine tool numerical control mechanism, thereby establishing a data interaction channel. If data is transmitted through the TCP / IP protocol, secure communication between cross-platform and cross-manufacturer devices is supported to ensure the compatibility and stability of the data transmission channel. The communication link between the central control unit and the machine tool numerical control mechanism is established, The central control unit sends a communication protocol handshake signal (such as identity authentication and data transmission format agreement) to the machine tool's numerical control mechanism to confirm that the communication parameters on both sides are consistent. This process follows the standardized process of industrial communication. Taking the Modbus protocol as an example, the communication status is confirmed through function codes (Function Code) and exception codes (Exception Code). This ensures that parameters such as baud rate, data bits, stop bits, and parity are consistent between the two parties, avoiding data transmission errors caused by communication parameter mismatches.

[0041] Step 2: The central control unit obtains the machining program for the hard and brittle workpiece 12 and generates ablation-side collaborative data and milling-side collaborative data based on the machining program for the hard and brittle workpiece 12. The machining program for the hard and brittle workpiece 12 can be obtained by importing it through the CNC machine tool, other external tools (such as a USB flash drive), or a client.

[0042] Step 3: The central control unit sends a driving coordination instruction and an ablation coordination instruction to the robot arm control module and the laser ablation control module respectively according to the ablation end coordination data.

[0043] Step 4: The robot control module interprets the drive coordination instruction into a drive control signal for the six-degree-of-freedom robot 4, and the laser ablation control module interprets the ablation coordination instruction into a drive control signal for the laser ablation mechanism, so that the laser ablation mechanism cooperates with the six-degree-of-freedom robot 4 to perform laser ablation processing on the hard and brittle material workpiece 12 according to the specified trajectory and speed; Step 5: The central control unit sends a milling coordination instruction to the machine tool numerical control mechanism according to the milling end coordination data. The machine tool numerical control mechanism runs the hard and brittle material workpiece 12 processing program according to the milling coordination instruction, and controls the machine tool spindle unit 2 to move so that the milling tool assembly follows the specified trajectory (such as Figure 3 As shown, starting from the starting station 18 of the milling trajectory, passing through the basic ablation trajectory 13 in the middle, and finally landing at the ending station 19 of the milling trajectory, the entire hard and brittle material workpiece 12 is covered in the entire process. The area to be processed 17) and the speed of the hard and brittle material workpiece 12 are milled at a speed that lags behind the laser ablation processing.

[0044] Example 2 This embodiment discloses a system and method for collaborative laser ablation and milling of hard and brittle materials. As a preferred embodiment of the present invention, based on Example 1, in step 2 of the collaborative processing method, the machining program for the hard and brittle workpiece 12 is preferably acquired by importing it from a machine tool CNC mechanism. This also includes active and passive acquisition.

[0045] Passive acquisition is a physical connection established between the machine tool CNC mechanism and the central control unit based on the industrial communication interface, which directly transmits the workpiece processing program to the central control unit in binary or text format.

[0046] Active acquisition involves the central control unit using a "producer-consumer model" to send a read instruction to the machine tool's numerical control mechanism to retrieve the workpiece processing program. In this model, the machine tool's numerical control mechanism acts as the data producer and the central control unit acts as the consumer. The central control unit specifies the storage path or number of the target program (e.g., by searching through the G-code program name). For example, in a custom TCP / IP-based communication protocol, the central control unit sends a request data packet containing program path information. After receiving the request, the machine tool's numerical control mechanism parses the data packet and locates the target program. The machine tool's numerical control mechanism responds to the instruction and transfers the workpiece processing program in binary or text format (e.g., an NC code file) to the central control unit's cache or storage module.

[0047] To ensure reliable data transmission, a block transmission + verification mechanism, such as LRC (Longitudinal Redundancy Check) or CRC (Cyclic Redundancy Check), is used between the machine tool CNC mechanism and the central control unit. Taking CRC verification as an example: before sending data, the machine tool CNC mechanism calculates a CRC checksum based on the data content and appends it to the end of the data packet. After receiving the data, the central control unit performs an integrity check on the workpiece processing program. This involves recalculating the data's CRC checksum and comparing it with the received checksum. If the comparison is consistent, the verification is considered passed and the next step of the analysis process is entered. If the comparison is inconsistent, an error feedback is sent to the machine tool CNC mechanism, which retransmits the workpiece processing program, thus ensuring that the data is not lost or tampered with.

[0048] Example 3 This embodiment discloses a system and method for collaborative processing of hard and brittle materials by laser ablation and milling. As a preferred embodiment of the present invention, based on embodiment 1 or 2, in step 2 of the collaborative processing method, in the process of generating collaborative data of the milling end based on the processing program of the hard and brittle material workpiece 12, the lag time interval of the milling process relative to the laser ablation process is generated. Assume that the average temperature of the current ablation area 20 is The maximum temperature at which milling can be performed is According to Newton's law of cooling, it can be calculated that the hard and brittle materials Cool to The time required, which is also the minimum value of the lag time interval Specifically: Newton's law of cooling is In this formula, The rate of heat loss, represents the convective heat transfer coefficient, represents the surface area of an object, Indicates the current temperature of the object, Indicates the ambient temperature.

[0049] The Newton's law of cooling formula is applied to this technical solution. In order to simplify the calculation, it is assumed that the specific heat capacity, mass, surface area and ambient temperature of the object remain constant. After integrating the Newton's law of cooling formula, the formula 1 can be obtained. In this formula, is the minimum hysteresis time interval, is the mass of the current ablation region 20 of the hard and brittle material workpiece 12, is the specific heat capacity of the hard and brittle material workpiece 12, is the convective heat transfer coefficient, is the surface area of the current ablation region 20 of the hard and brittle material workpiece 12; is the average temperature of the current ablation area 20, The maximum temperature at which milling can be performed; is the ambient temperature.

[0050] Since the laser focus is at the nanometer level and moves at a high speed along a specific trajectory, e.g. Figure 3 The laser ablation processing track starting station 14 and Figure 4 The ablation region 20 shown is generally set to be a region of a hard and brittle material workpiece 12 with a length, width and height of 、 、 The cuboid ( Figure 4 Shows the length and width of the ablation area 20), then 、 , Represents the density of the hard and brittle material workpiece 12; thus, formula 1 is converted into , and then calculate the minimum lag time interval , then let .

[0051] Ceramic matrix composites are typical hard and brittle materials. They are a type of composite material with ceramic as the matrix and various fibers as the reinforcement phase. They have the characteristics of hard and brittle materials such as high brittleness, high hardness, and thermal stability. Take the laser ablation and milling collaborative processing of ceramic matrix composites as an example: First, a milling program (ie, a processing program for a hard and brittle material workpiece 12 ) is compiled according to the processing characteristics of the ceramic matrix composite workpiece, which includes a CNC milling trajectory.

[0052] Then, according to the processing requirements of the ceramic matrix composite workpiece, the laser ablation power, ultrasonic vibration frequency and amplitude and other parameters are set in the collaborative control device 3, as well as the following parameters related to the ceramic matrix composite: the specific heat capacity of the ceramic matrix composite ; The convective heat transfer coefficient between the ceramic matrix composite and air is ; Ambient temperature ; Density of ceramic matrix composite workpiece to be processed ; Average temperature of the ablated area 20 The ablated area 20 is a length and width of , height is The maximum temperature at which milling can be performed .

[0053] Finally, the collaborative processing of laser ablation and milling is carried out according to the collaborative processing method of the present technical solution. In the process of .Right now Milling should lag at least 28 seconds behind laser ablation. The surface temperature of the ceramic matrix composite workpiece rises sharply after laser ablation. Direct milling will reduce the service life of the milling tool assembly. Therefore, milling should be started at least 28 seconds after laser ablation to allow sufficient time for the ablated area 20 to cool.

[0054] Example 4 This embodiment discloses a system and method for collaborative processing of hard and brittle materials by laser ablation and milling. As a preferred embodiment of the present invention, based on embodiment 1 or 2, in step 2 of the collaborative processing method, in the process of generating collaborative data of the milling end based on the processing program of the hard and brittle material workpiece 12, the lag time interval of the milling process relative to the laser ablation process is generated. , which is different from Example 3 in that this embodiment uses the central control unit in the collaborative control device 3 to retrieve the workpiece material database, obtain the target material's thermodynamic property parameters such as thermal conductivity, specific heat capacity, and melting point, and simultaneously read the processing characteristic data such as the heat resistance limit temperature of the milling tool assembly. Based on the Fourier heat conduction equation, combined with ablation parameters such as laser energy density and spot diameter, the temperature field change process of the laser ablation area 20 is simulated through the finite element thermal analysis algorithm. For example, for hard and brittle ceramic materials, a three-dimensional heat conduction model is established using simulation software such as ANSYS to calculate the time required for the ablation area 20 to drop from the maximum temperature to the milling safety temperature, thereby determining the execution time interval (i.e., the lag time interval). .

[0055] Example 5 This embodiment discloses a system and method for collaborative laser ablation and milling processing of hard and brittle materials. As a preferred embodiment of the present invention, based on Embodiment 3 or 4, the process of generating collaborative ablation end data based on the machining program of the hard and brittle material workpiece 12 includes generating a laser ablation machining trajectory, and generating the laser ablation machining trajectory includes the following steps: The central control unit calls the G-code parser, which scans the workpiece machining program line by line, identifying instructions related to milling (such as G00 / G01 linear interpolation, G02 / G03 circular interpolation, F feed rate, S spindle speed, etc.). Taking the recursive descent parser as an example, it breaks down the G-code string into lexical units (tokens), such as coordinate values, instruction codes, and parameters, according to the G-code syntax rules. During the parsing process, the parser verifies the legitimacy of the instructions by matching syntax rules (such as the G01 instruction must be followed by X, Y, and Z coordinate parameters). For identified instructions related to milling, the parser extracts and stores them, filtering out non-trajectory instructions (such as M-code auxiliary functions and T-code tool change instructions), retaining only trajectory instructions related to the movement of the milling tool assembly.

[0056] Interpolate the trajectory instructions. Linear interpolation: The linear interpolation algorithm is used to calculate the intermediate interpolation points through the start and end point coordinates to form a continuous straight line trajectory. For example, for the G01, X10, Y20, Z30 and F100 instructions, the parser generates a series of small line segments between the start and end points according to the start and end point coordinates (X10, Y20, Z30) and the feed rate F100. These line segments are connected to form a straight line trajectory. Arc interpolation: The circular interpolation algorithm is used to generate arc trajectory points according to the center coordinates, radius and rotation direction (clockwise / counterclockwise). For example, for the G02, X20, Y30, I10, and J0 instructions, the parser generates discrete points on the arc trajectory by calculating the offset of the circle center relative to the start point (I10, J0) and combining it with the end point coordinates (X20, Y20).

[0057] The discrete trajectory instruction segments are converted into a continuous sequence of trajectory points, forming the basic data structure of the workpiece milling operation trajectory (such as a point set + motion parameter array). During the conversion process, motion attributes such as speed and acceleration are assigned to each trajectory point based on the motion type and parameters to ensure the accuracy and stability of the subsequent machining process.

[0058] The central control unit smoothes the underlying data structure of the milling trajectory, employing either cubic spline interpolation or B-spline curve fitting algorithms. For example, cubic spline curves require continuity of position, first-order derivatives, and second-order derivatives at the connection points of adjacent curve segments. This eliminates sudden speed changes at the junctions of command segments, ensuring the continuity and stability of the milling motion and minimizing the impact of motion shock on the workpiece and equipment.

[0059] For the smoothed milling trajectory data, the trajectory coordinate data is converted from the machine tool coordinate system to the reference coordinate system of the laser ablation system to generate the basic ablation trajectory for laser ablation. This conversion is based on a homogeneous transformation matrix. In practical applications, high-precision calibration tools (such as laser trackers) can be used to measure the coordinates of at least three non-collinear points in the two coordinate systems. The homogeneous transformation matrix is optimized using the least squares method to control the coordinate transformation error within ±0.01mm, ensuring the consistency of the trajectory spatial position.

[0060] Finally, since the milling processing trajectory overlaps with the basic ablation trajectory, in order to avoid delayed milling processing, a non-ablation segment trajectory is added to the end of the basic ablation trajectory to generate a laser ablation processing trajectory (including the laser ablation processing trajectory starting station 14 and the laser ablation processing trajectory ending station 15).

[0061] Example 6 This embodiment discloses a system and method for collaborative laser ablation and milling of hard and brittle materials. As a preferred embodiment of the present invention, based on Example 5, a non-ablation segment track is added to the end of the basic ablation track, including: Based on the hysteresis time interval And the machining feed speed of the machine tool spindle unit 2 , using the formula Calculate the distance before and after execution This calculation is based on the relationship between speed, time and displacement in kinematics, ensuring that the milling process is carried out after the laser ablation area 20 cools down. At the same time, the milling tool assembly diameter is taken into account. ( Determines the contact range and heat-affected zone when the tool cuts into the material), through the formula Calculate the length of the non-ablative segment trajectory ,in The purpose of introducing is to prevent the milling cutter from cutting into the high-temperature ablation area 20, which may cause tool wear or workpiece cracking.

[0062] Based on the coordinates of the end point of the basic ablation trajectory, a vector extension is performed along the ablation motion direction (determined by the tangent direction of the trajectory point), and the extension length is , thereby generating the laser ablation processing trajectory.

[0063] Furthermore, in actual application, trajectory planning and control verification can be added, such as: the central control unit uses virtual simulation technology to simulate and verify the generated laser ablation processing trajectory and control logic in the digital twin environment. By importing the three-dimensional model of the hard and brittle material workpiece 12, the virtual model of the laser ablation system and the machine tool milling system, setting the processing parameters and motion constraints, and running the simulation program. Based on the collision detection algorithm in computer graphics (such as the hierarchical bounding box method), check whether the laser ablation processing trajectory will cause the laser ablation system and the machine tool spindle unit 2, and whether there is a risk of collision between the hard and brittle material workpiece 12, and verify the rationality of the ablation-milling time interval and the trajectory connection. If problems are found in the trajectory planning or control logic during the simulation process (such as collision risk, the ablation area 20 is not completely cooled, etc.), the central control unit automatically adjusts the relevant parameters (such as 、 or trajectory path), regenerate the laser ablation processing trajectory, and perform simulation verification again until the processing requirements are met to ensure the safety and efficiency of the actual processing process.

[0064] Example 7 This embodiment discloses a system and method for collaborative laser ablation and milling of hard and brittle materials. As a preferred embodiment of the present invention, based on Example 5 or Example 6, in the process of generating collaborative ablation end data based on the machining program of the hard and brittle material workpiece 12, it also includes generating a trajectory segmentation mark, which serves as a basis for the laser ablation control module to control the operation of the laser ablation mechanism. The trajectory segmentation mark includes traversing the laser ablation machining trajectory point set, marking points in the basic ablation trajectory as "ablation task segments", and marking points in the non-ablation segment trajectory as "non-ablation segments".

[0065] Therefore, when the laser ablation mechanism and the six-degree-of-freedom robotic arm 4 cooperate to perform laser ablation processing on a hard and brittle material workpiece 12 according to a specified trajectory and speed, the control logic is as follows: the central control unit simultaneously sends ablation coordination instructions and drive coordination instructions to the laser ablation control module and the robotic arm control module, respectively. After receiving the drive coordination instructions, the robotic arm control module converts the trajectory data into motion control instructions for each joint of the six-degree-of-freedom robotic arm 4 based on the planned laser ablation processing trajectory data (including trajectory point coordinates and motion speed) based on G-code parsing and motion control principles. Specifically, the DH parameter method can be used to establish a robotic arm kinematic model. Using an inverse kinematics solution algorithm (such as the Newton-Raphson iteration method), the trajectory points in the Cartesian coordinate system are converted into a sequence of joint angle values. These angle values are then converted into pulse signals or analog voltage signals to drive the servo motors of each joint to control the movement of the six-degree-of-freedom robotic arm 4. After receiving the coordinated ablation command, the laser ablation control module controls the power output of the laser ablation mechanism based on the trajectory segmentation markings ("ablation task segment" or "non-ablation segment") and laser ablation parameters (such as laser power parameters) while the 6-DOF robotic arm 4 moves along the laser ablation processing trajectory. When in the "ablation task segment," the module outputs a corresponding laser power control signal (drive signal) based on the preset laser ablation parameters, thereby controlling the operation of the laser ablation mechanism. When entering the "non-ablation segment," the module immediately cuts off the power to the laser ablation mechanism, stopping laser output.

[0066] At the same time, the laser ablation control module and / or the robotic arm control module records the start time of the laser ablation task And synchronize the timestamp to the system clock of the central control unit, and then control the CNC mechanism of the machine tool in the Start the milling task, where On this basis, the control logic of the collaborative control device 3 for the machine tool milling system is as follows: When the system clock reaches Before the time, the central control unit sends a pre-start instruction to the CNC machine tool to inform it to prepare to receive the milling task. After receiving the pre-start instruction, the CNC machine tool will allocate internal resources (such as tool path cache, spindle acceleration preparation, etc.). At this moment, the central control unit sends a formal milling start signal (i.e., milling coordination instruction) to the machine tool's CNC mechanism. Upon receiving the instruction, the CNC mechanism immediately initiates the milling task (i.e., step five). During the machining process, the CNC mechanism monitors parameters such as spindle load and feed speed in real time, ensuring machining accuracy and stability through feedback control mechanisms.

[0067] Example 8 This embodiment discloses a system and method for collaborative processing of hard and brittle materials by laser ablation and milling. As a preferred embodiment of the present invention, that is, based on any one of embodiments 1 to 7, its laser ablation system also includes a visual obstacle avoidance unit, and the visual obstacle avoidance unit includes a camera device 5 and an image posture recognition unit; the camera device 5 is physically connected in communication with the image posture recognition unit for real-time acquisition of image data of the machine tool spindle unit 2 and the hard and brittle material workpiece 12, and transmission of the image data to the image posture recognition unit; the image posture recognition unit is physically connected in communication with the central control unit for identifying the real-time dynamic posture information of the machine tool spindle unit 2 and the hard and brittle material workpiece 12 through image data, and transmission of the real-time dynamic posture information to the central control unit, so that the central control unit controls the six-degree-of-freedom robotic arm 4 through the robotic arm control module to avoid the machine tool spindle unit 2 and the hard and brittle material workpiece 12.

[0068] Camera device 5 can utilize an industrial-grade, high-resolution camera to ensure it can capture rapid, dynamic changes in the machine tool spindle unit 2 and the workpiece. Initialization commands can be sent via the collaborative control device 3 to set parameters such as exposure time, gain, and white balance for camera device 5 to adapt to the lighting conditions of the machining environment and ensure the clarity and accuracy of captured images. During the collaborative machining task, camera device 5 continuously captures image data of the machine tool spindle unit 2 and the workpiece area at a set frame rate and transmits this image data to the image pose recognition unit.

[0069] After receiving the raw image data, the image pose recognition unit first performs image preprocessing. Digital image processing techniques, including grayscale conversion, are used to convert color images into grayscale images, reducing data processing workload. Gaussian or median filtering algorithms are used to remove image noise and smooth image edges. Histogram equalization is used to enhance image contrast and highlight the contour features of the machine tool spindle unit 2 and the hard and brittle workpiece 12, providing high-quality image data for subsequent pose recognition. The image pose recognition unit uses computer vision feature extraction algorithms, such as SIFT (Scale-Invariant Feature Transform), SURF (Speeded Robust Features), or ORB (Oriented Rapid Feature Points and Rotation Brief Descriptors), to extract key feature points (such as corners and edges) of the machine tool spindle unit 2 and the hard and brittle material workpiece 12. Simultaneously, a pre-trained deep learning-based object detection model (such as YOLO and FasterR-CNN) identifies the machine tool spindle unit 2 and the hard and brittle material workpiece 12 in the image, determining their position and extent within the image. The extracted feature points are combined with the object detection results to construct a feature descriptor for the target object, which is used for subsequent pose calculation. Pose Calculation: Based on the extracted feature points and the 3D model of the target object (pre-stored in the image pose recognition unit), the PnP (Perspective-n-Point) algorithm is used to calculate the six-degree-of-freedom pose (3D position and 3D attitude) of the machine tool spindle unit 2 and the hard and brittle workpiece 12. Based on the principle of perspective projection, the PnP algorithm establishes a correspondence between the image plane feature points and the 3D model points to determine the pose parameters of the target object in the coordinate system of the camera device 5. Using the pre-calibrated transformation relationship between the camera device 5 and the reference coordinate system, the pose parameters are converted to the reference coordinate system of the laser ablation system. This results in real-time dynamic pose information for the machine tool spindle unit 2 and the hard and brittle workpiece, which is then transmitted to the central control unit.

[0070] The central control unit constructs a collision detection model based on the three-dimensional models of the machine tool spindle unit 2, the hardened workpiece, and the laser ablation system (the six-degree-of-freedom robotic arm 4 and the laser ablation mechanism). A hierarchical bounding box method is used to simplify the complex three-dimensional model, dividing it into multiple levels of bounding box structures to reduce the computational complexity of collision detection. Based on the real-time pose information of the machine tool spindle unit 2, the hardened workpiece, and the laser ablation system, the central control unit updates the position and posture of each component in the collision detection model in real time. The presence of collision interference is determined by calculating whether the motion trajectory of the laser ablation system intersects with the bounding boxes of the machine tool spindle unit 2, the central control unit, and the workpiece. A spatial segmentation algorithm is used to divide the machining space into multiple subspaces. Only bounding boxes within subspaces where collisions may occur are checked for intersection, further improving detection efficiency. If bounding box intersection is detected, a collision risk is determined; otherwise, the system is considered to be operating normally and there is no collision interference. When the central control unit detects a collision, it triggers obstacle avoidance path planning. Using motion planning algorithms such as RRT (Rapidly Expanding Random Trees), the system searches for a collision-free, obstacle-avoiding path within the processing space, starting with the current laser ablation system's position and aiming for a safe position after avoiding the collision zone. Taking into account the kinematic constraints of the 6-DOF robot (e.g., joint angle limits and speed limits), the generated path is optimized during the path planning process to ensure the 6-DOF robot can move safely and quickly along the planned path. The robotic arm control module converts the obstacle avoidance path planned by the central control unit into joint motion instructions for the six-degree-of-freedom robotic arm 4, which are then transmitted to the servo drivers of each joint of the six-degree-of-freedom robotic arm 4. The servo drivers drive the robotic arm's joints according to the instructions, allowing the laser ablation system to follow the obstacle avoidance path, avoiding the machine tool spindle unit 2 and the workpiece. During the obstacle avoidance process, the camera device 5 continuously monitors environmental changes, and the collaborative control device 3 updates position information and collision detection in real time to ensure the effectiveness and safety of the obstacle avoidance action. Once the laser ablation system successfully avoids the collision zone, the central control unit reassesses the processing task and, if conditions permit, resumes the normal collaborative processing process. Otherwise, the obstacle avoidance strategy continues or the processing task is paused.

[0071] Example 9 This embodiment discloses a system and method for collaborative laser ablation and milling of hard and brittle materials. As a preferred embodiment of the present invention, based on any of Examples 1 to 8, the collaborative control device 3 further includes a human-machine interface unit physically connected to the central control unit for inputting corresponding processing parameters and control instructions, as well as displaying collaborative processing parameters. Based on this, during the processing preparation phase, the processing can be started automatically or manually.

[0072] Automatically start processing: Once the central control unit has generated collaborative data for both the ablation and milling ends, it automatically triggers the automated workflow trigger command, entering the processing task initiation phase (Step 3). The advantage of automatic processing is that it saves time and eliminates the need for personnel to constantly monitor the processing process.

[0073] Manually start processing: After the central control unit completes the generation of the coordinated data for the ablation and milling ends, the human-machine interface displays a "Loading Complete" prompt. When the operator sends a manual start signal using the "Start" button on the human-machine interface, the signal is transmitted to the central control unit via the PLC (Programmable Logic Controller) or dedicated I / O interface. After the central control unit recognizes the signal, the processing task starts (i.e., step three). The advantage of manually starting processing is that it allows technicians time to check the equipment, processing parameters, and other aspects. Example 10 This embodiment discloses a laser ablation and milling collaborative processing system and method for hard and brittle materials, as a preferred embodiment of the present invention, that is, based on any one of Examples 1 to 9, such as Figure 2 As shown, the laser ablation mechanism includes a laser processing head 6 and a laser generator 7; the laser generator 7 is connected to the laser ablation control module and is used to emit a laser beam according to the drive signal emitted by the laser ablation control module; the laser processing head 6 is connected to the laser generator 7 and is used to focus the laser beam emitted by the laser generator 7 on a hard and brittle material workpiece 12.

[0074] After receiving control signals (including power and pulse frequency) from the laser ablation control module, the laser generator 7 operates based on the principle of stimulated emission of radiation. Taking a solid-state laser as an example, the internal gain medium achieves population inversion under the stimulation of the pump source. The control system of the laser generator 7 adjusts the pump source current based on input commands, thereby controlling the laser energy generated by the gain medium. For example, when laser power needs to be increased, the pump source current is increased to enable more particles to achieve energy level transitions, thereby increasing the laser output power. Simultaneously, a modulation circuit controls the laser pulse frequency and pulse width to meet the requirements of different processing stages. The laser processing head 6 has a built-in optical focusing system, including optical elements such as lenses and reflectors. After the laser beam output from the laser generator 7 enters the laser processing head 6, it first passes through a collimating lens to adjust the divergent beam into parallel light, and then passes through a focusing lens to focus the parallel light onto the surface of the workpiece. The focal length of the focusing lens is selected according to the processing requirements. The shorter the focal length, the smaller the focused spot and the higher the energy density, which is suitable for fine processing. The laser processing head 6 realizes rapid scanning and guiding of the light beam through a two-dimensional galvanometer system driven by a servo motor. The galvanometer accurately adjusts the angle of the reflector according to the trajectory coordinate instruction sent by the laser ablation control module, so that the laser beam follows the preset trajectory (such as Figure 4 The laser focusing track 16 shown in FIG. 1 is moved until the laser ablation processing of the current ablation area 20 is completed. After the laser ablation processing of the current ablation area 20 is completed, the six-degree-of-freedom robot 4 moves the laser processing head 6 to the next ablation area 20 along the laser ablation processing track.

[0075] Example 11 This embodiment discloses a system and method for collaborative processing of laser ablation and milling of hard and brittle materials. As a preferred embodiment of the present invention, that is, based on Example 9 or 10, its collaborative control device 3 also includes a laser focusing adjustment unit and a laser rangefinder 8; the laser rangefinder 8 is mounted on a six-degree-of-freedom robotic arm 4 and establishes a physical communication connection with the laser focusing adjustment unit, and is used to measure the real-time distance between the laser processing head 6 and the hard and brittle material workpiece 12 according to the projection of the laser beam emitted by the laser processing head 6 on the surface of the hard and brittle material workpiece 12, and transmit the real-time distance to the laser focusing adjustment unit; the laser focusing adjustment unit establishes a physical communication connection with the robotic arm control module, and is used to obtain a distance adjustment signal according to the real-time distance between the laser processing head 6 and the hard and brittle material workpiece 12, and transmit the distance adjustment signal to the robotic arm control module, and the robotic arm control module controls the six-degree-of-freedom robotic arm 4 to adjust the distance between the laser processing head 6 and the hard and brittle material workpiece 12, so that the laser beam emitted by the laser processing head 6 is always focused on the surface of the hard and brittle material workpiece 12.

[0076] The raw data collected by the laser rangefinder is filtered to remove noise interference. Median filtering or Kalman filtering algorithms are used to improve data accuracy and stability. Because factors such as optical component manufacturing errors and ambient temperature fluctuations can affect measurement accuracy, the laser focus adjustment unit has a built-in calibration module for regular self-calibration. During calibration, the measurement error is calculated by measuring a reference object with a known standard distance, and an error compensation table is generated. During actual measurement, the measured data is corrected according to the error compensation table to ensure that the distance data accuracy meets processing requirements.

[0077] The laser focus adjustment unit compares the processed and calibrated distance data with the preset focus distance. If there is a deviation, the laser focus self-adjustment module is triggered. Based on a PID control algorithm, the laser focus self-adjustment module calculates the adjustment amount for each joint of the 6-DOF robotic arm 4. The robotic arm control module drives the 6-DOF robotic arm 4 to adjust its movements, thereby adjusting the position of the laser processing head 6 to restore the distance between the laser processing head 6 and the workpiece surface to the optimal focus distance. This ensures that the laser beam is always focused on the workpiece surface, guaranteeing the accuracy and quality of the laser ablation process.

[0078] Example 12 This embodiment discloses a system and method for collaborative laser ablation and milling processing of hard and brittle materials. As a preferred embodiment of the present invention, based on Example 11, its laser ablation system also includes a freeze dryer 10, and the freeze dryer 10 establishes a physical control connection with the central control unit to provide a dry gas source for the laser generator 7.

[0079] Example 13 This embodiment discloses a system and method for collaborative processing of hard and brittle materials by laser ablation and milling. As a preferred embodiment of the present invention, that is, based on any one of embodiments 1 to 12, it also includes a power distribution cabinet 9, and the power distribution cabinet 9 is respectively connected to the laser ablation system and the collaborative control device 3 for power supply.

Claims

1. A laser ablation and milling collaborative processing system for hard and brittle materials, characterized by: It comprises a machine tool milling system, a laser ablation system and a coordinated control device (3); the machine tool milling system comprises a machine tool numerical control mechanism, a machine tool main body mechanism (1) and a machine tool spindle unit (2); the laser ablation system comprises a six-degree-of-freedom robotic arm (4) and a laser ablation mechanism; the coordinated control device (3) comprises a central control unit, a robotic arm control module and a laser ablation control module; The central control unit establishes physical communication connections with the machine tool numerical control mechanism, the laser ablation control module and the robot arm control module respectively, and is used to generate ablation end coordination data and milling end coordination data based on a hard and brittle material workpiece (12) processing program, and sends a driving coordination instruction and ablation coordination instruction to the robot arm control module and the laser ablation control module respectively according to the ablation end coordination data, and sends a milling coordination instruction to the machine tool numerical control mechanism according to the milling end coordination data; The robotic arm control module establishes a physical control connection with the six-degree-of-freedom robotic arm (4) for parsing the drive coordination instruction into a drive control signal for the six-degree-of-freedom robotic arm (4); the six-degree-of-freedom robotic arm (4) is mounted on the front end of the workbench (1.1) of the machine tool main body (1) for executing each joint action according to the drive control signal issued by the robotic arm control module; The laser ablation control module establishes a physical control connection with the laser ablation mechanism, and is used to resolve the ablation coordination instruction into a drive control signal for the laser ablation mechanism; the laser ablation mechanism is mounted on the execution end of the six-degree-of-freedom robotic arm (4), and is used to perform laser ablation processing on a hard and brittle material workpiece (12) according to a specified trajectory and speed in coordination with the joint movements of the six-degree-of-freedom robotic arm (4) based on the drive control signal issued by the laser ablation control module; The machine tool spindle unit (2) is mounted on the machine tool main body mechanism (1), and a milling tool assembly for milling a hard and brittle material workpiece (12) is installed on the machine tool spindle unit (2); the machine tool numerical control mechanism and the machine tool spindle unit (2) are physically controlled and connected via a servo control circuit, and are used to control the movement of the machine tool spindle unit (2) according to a milling coordination instruction, so that the milling tool assembly performs milling processing on the hard and brittle material workpiece (12) at a specified trajectory and speed, which lags behind the laser ablation processing.

2. The laser ablation and milling collaborative processing system for hard and brittle materials according to claim 1, characterized in that: The laser ablation system further comprises a visual obstacle avoidance unit, and the visual obstacle avoidance unit comprises a camera device (5) and an image posture recognition unit; the camera device (5) is physically connected to the image posture recognition unit for real-time acquisition of image data of the machine tool spindle unit (2) and the hard and brittle material workpiece (12), and the image data is transmitted to the image posture recognition unit; the image posture recognition unit is physically connected to the central control unit for real-time dynamic posture information of the machine tool spindle unit (2) and the hard and brittle material workpiece (12) through image data, and the real-time dynamic posture information is transmitted to the central control unit, so that the central control unit controls the six-degree-of-freedom robot arm (4) to avoid the machine tool spindle unit (2) and the hard and brittle material workpiece (12) through the robot arm control module.

3. The laser ablation and milling collaborative processing system for hard and brittle materials according to claim 1, characterized in that: The laser ablation mechanism comprises a laser processing head (6) and a laser generator (7); the laser generator (7) is connected to the laser ablation control module and is used to emit a laser beam according to a drive control signal emitted by the laser ablation control module; the laser processing head (6) is connected to the laser generator (7) and is used to focus the laser beam emitted by the laser generator (7) on a hard and brittle material workpiece (12).

4. The laser ablation and milling collaborative processing system for hard and brittle materials according to claim 3, characterized in that: The collaborative control device (3) further includes a laser focus adjustment unit and a laser rangefinder (8); the laser rangefinder (8) is mounted on the six-degree-of-freedom robotic arm (4) and establishes a physical communication connection with the laser focus adjustment unit, and is used to measure the real-time distance between the laser processing head (6) and the hard and brittle material workpiece (12) based on the projection of the laser beam emitted by the laser processing head (6) on the surface of the hard and brittle material workpiece (12), and transmit the real-time distance to the laser focus adjustment unit; the laser focus adjustment unit establishes a physical communication connection with the robotic arm control module, and is used to obtain a distance adjustment signal based on the real-time distance between the laser processing head (6) and the hard and brittle material workpiece (12), and transmit the distance adjustment signal to the robotic arm control module, and the robotic arm control module controls the six-degree-of-freedom robotic arm (4) to adjust the distance between the laser processing head (6) and the hard and brittle material workpiece (12), so that the laser beam emitted by the laser processing head (6) is always focused on the surface of the hard and brittle material workpiece (12).

5. The laser ablation and milling collaborative processing system for hard and brittle materials according to claim 4, characterized in that: The laser ablation system further comprises a freeze dryer (10), and the freeze dryer (10) establishes a physical control connection with the central control unit, and is used to provide a dry gas source for the laser generator (7).

6. The laser ablation and milling collaborative processing system for hard and brittle materials according to claim 1, characterized in that: It also includes a power distribution cabinet (9), and the power distribution cabinet (9) is respectively connected to the laser ablation system and the collaborative control device (3) for power supply.

7. A method for collaborative laser ablation and milling of hard and brittle materials, characterized in that: The following processing control steps are implemented using the laser ablation and milling collaborative processing system as described in any one of claims 1 to 6: The laser ablation and milling collaborative processing system is started and initialized; The central control unit obtains a machining program of a hard and brittle material workpiece (12), and generates ablation end collaborative data and milling end collaborative data based on the machining program of the hard and brittle material workpiece (12); The central control unit sends driving coordination instructions and ablation coordination instructions to the robot arm control module and the laser ablation control module respectively according to the ablation end coordination data; The robot control module interprets the driving coordination instruction into a driving control signal for the six-degree-of-freedom robot (4), and the laser ablation control module interprets the ablation coordination instruction into a driving control signal for the laser ablation mechanism, so that the laser ablation mechanism cooperates with the six-degree-of-freedom robot (4) to perform laser ablation processing on the hard and brittle material workpiece (12) according to a specified trajectory and speed; The central control unit sends a milling coordination instruction to the machine tool numerical control mechanism according to the milling end coordination data. The machine tool numerical control mechanism runs a hard and brittle material workpiece (12) processing program according to the milling coordination instruction, and controls the movement of the machine tool spindle unit (2) so that the milling tool assembly performs milling processing on the hard and brittle material workpiece (12) at a specified trajectory and speed, which lags behind the laser ablation processing.

8. The laser ablation and milling collaborative processing method for hard and brittle materials according to claim 7, characterized in that: The method for the central control unit to obtain the processing program of the hard and brittle material workpiece (12) includes active acquisition and passive acquisition; The active acquisition is as follows: the central control unit sends a processing program reading instruction to the machine tool numerical control mechanism based on the physical connection established between the industrial communication interface and the machine tool numerical control mechanism; the machine tool numerical control mechanism responds to the instruction and transmits the workpiece processing program in binary or text format to the central control unit; Passive acquisition means that the CNC mechanism of the machine tool directly transmits the workpiece processing program in binary or text format to the central control unit based on the physical connection established between the industrial communication interface and the central control unit; After receiving the workpiece processing program, the central control unit performs an integrity check on the workpiece processing program; if the check passes, it enters the next step of the analysis process; If the verification fails, an error feedback is sent to the machine tool CNC mechanism.

9. The laser ablation and milling collaborative processing method for hard and brittle materials according to claim 7, characterized in that: In the process of generating milling end collaborative data based on the machining program of hard and brittle material workpiece (12), including generating the lag time interval of milling processing relative to laser ablation processing ,Right now: Formula 1 is obtained based on Newton's law of cooling ;in is the minimum hysteresis time interval, is the mass of the current ablation area (20) of the hard and brittle material workpiece (12), is the specific heat capacity of the hard and brittle material workpiece (12), is the convective heat transfer coefficient, is the surface area of the current ablation region (20) of the hard and brittle material workpiece (12); is the average temperature of the current ablation area (20), The maximum temperature at which milling can be performed; is the ambient temperature; The current ablation region (20) of the hard and brittle material workpiece (12) is set to be a region with a length, width and height of 、 、 For a rectangular parallelepiped, we have 、 , represents the density of the hard and brittle material workpiece (12); thus, formula 1 is converted into , calculate the minimum lag time interval ,make .

10. The laser ablation and milling collaborative processing method for hard and brittle materials according to claim 9, characterized in that: In the process of generating ablation end collaborative data based on a machining program of a hard and brittle material workpiece (12), the process includes generating a laser ablation machining trajectory, and the generating of the laser ablation machining trajectory includes the following steps: The central control unit calls the G-code parser, scans the workpiece processing program line by line, identifies the instructions related to milling processing, filters out non-trajectory instructions, and only retains the trajectory instructions related to the movement of the milling tool assembly; Interpolate the trajectory instructions, and then convert the discrete trajectory instruction segments into a continuous trajectory point sequence to form the basic data structure of the workpiece milling machining trajectory; After smoothing the basic data structure of the milling machining trajectory, the central control unit converts the trajectory coordinate data from the machine tool coordinate system to the reference coordinate system of the laser ablation system to generate a basic ablation trajectory of laser ablation (13); A non-ablation segment track is added to the end of the basic ablation track (13) to finally generate a laser ablation processing track.

11. The laser ablation and milling collaborative processing method for hard and brittle materials according to claim 10, characterized in that: Adding a non-ablation segment trajectory at the end of the basic ablation trajectory (13) includes: calculating the minimum distance between the ablation area (20) and the milled area at the same time, that is, ,in Indicates the milling feed rate; considering the milling tool component diameter Under the condition of ,Right now Based on the coordinates of the end point of the basic ablation trajectory (13), the vector is extended along the ablation motion direction, and the extension length is .

12. The laser ablation and milling collaborative processing method for hard and brittle materials according to claim 10, characterized in that: The process of generating ablation end collaborative data based on the machining program of a hard and brittle material workpiece (12) also includes generating trajectory segmentation marks, which are used as a basis for the laser ablation control module to control the operation of the laser ablation mechanism; the trajectory segmentation marks include traversing the laser ablation machining trajectory point set, marking the points in the basic ablation trajectory (13) as "ablation task segments", and marking the points in the non-ablation segment trajectory as "non-ablation segments".

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