Cutting path planning method and system for intelligent disassembly of household appliance compressor

Abstract

The invention provides an intelligent disassembling and cutting path planning method and system for a household appliance compressor, and the method comprises the steps: scanning and modeling: carrying out the multi-view scanning of the compressor through an arm-mounted 3D camera, and generating a complete three-dimensional point cloud model; according to the cylindrical shape, a copper nozzle (A), a welding seam (C) and a supporting foot (D) are included; elliptical form: weld (F); dynamic path generation: cylindrical type: generating three offset annular paths (offset d1 / d2 / d3) by taking characteristic C / A / D as a reference; for the ellipse type, upwards shifting d5 by taking the feature F as a reference to generate a closed-loop ellipse path; and path data is transmitted to the cutting robot in real time to be executed. Triple dynamic adaptation is achieved through one-time scanning, specifically, protrusions on the surface of a compressor tank body are intelligently avoided, cylindrical / oval structure differences are compatible, and size deformation is absorbed; the cutting path is continuous without interruption, and the precision is + / -3mm; compared with manual work, the efficiency is greatly improved, and zero-intervention production is achieved.

Description

A cutting path planning method and system for intelligent disassembly of home appliance compressors Technical Field

[0001] This invention relates to the field of waste household appliance recycling and processing technology, and more specifically, to a cutting path planning method and system for intelligent dismantling of household appliance compressors. Background Technology

[0002] In existing technologies for cutting and disassembling compressors for household appliances such as air conditioners and refrigerators, there are two main methods: manual cutting and fixed-track CNC cutting. Manual cutting involves operators holding a plasma cutting torch and visually identifying features such as welds and edges on the compressor. The operator relies on experience to manually control the torch's movement, lacking precise positioning and path planning; cutting accuracy depends entirely on the operator's skill. Fixed-track CNC cutting uses mechanical clamps to hold a single-specification cylindrical compressor (not suitable for elliptical structures), pre-programs a fixed cutting path, and the cutting torch moves along the preset trajectory. This method can only handle standard-sized workpieces and cannot adapt to changes in dimensional tolerances or transportation deformation. Furthermore, it requires manual mold changes or program switching. Both methods have the following drawbacks:

[0003] (1) Major security risks:

[0004] Manual cutting: Operators are directly exposed to the plasma torch operating area. Due to the lack of protective isolation and path control, the incidence of accidents such as high-temperature molten slag splash (temperature >1500℃), torch burns and accidental cutting injuries is significantly higher than that of automated production lines (statistical accident rate >3 cases / thousand units).

[0005] Fixed CNC cutting: Relies on rigid positioning of mechanical fixtures. When the workpiece is displaced due to clamping tolerance (>±2mm) or transportation deformation (support warping ≥5mm), it will cause torch collision or equipment emergency stop failure. The mean time between failures (MTBF) is <200 hours.

[0006] (2) Poor environmental performance:

[0007] Manual cutting: Smoke and dust are not collected and spread directly, polluting the environment;

[0008] Fixed CNC cutting: The dust collection range does not match the preset path, the dust capture efficiency is ≤50%, and residual dust overflows and pollutes through gaps.

[0009] (3) Occupational health hazards:

[0010] Manual / fixed CNC cutting: Long-term exposure to noise ≥100dB, metal fumes (containing Fe and Cu particles), and arc light environment can easily lead to respiratory diseases, hearing damage, and eye burns.

[0011] (4) Insufficient adaptability and accuracy:

[0012] Manual cutting: Relies on experience to determine the path, the path is irregular, and it is easy to damage recyclable parts such as copper nozzle (feature A) and bracket (feature B), resulting in a decrease in material recycling rate of ≥30%;

[0013] Fixed CNC cutting: only suitable for standard cylindrical shells, unable to handle elliptical curvature shells and dimensional fluctuations; model switching relies on manual intervention, and the fixed trajectory results in a scrap rate of ≥15%. Summary of the Invention

[0014] To address the aforementioned shortcomings, this invention provides a cutting path planning method and system for intelligent disassembly of home appliance compressors. This method focuses on intelligent obstacle avoidance of protrusions on the compressor tank surface, adaptation to structural differences, and compatibility with dimensional deformation. It achieves one-time planning and dynamic adaptation through visual guidance, and the cutting trajectory is continuous and efficient, thereby improving disassembly efficiency.

[0015] In the first aspect, the present invention provides a cutting path planning method for intelligent disassembly of home appliance compressors, which includes the following steps: S1. Scanning the compressor on the tooling table from multiple perspectives using an arm-mounted 3D vision camera to obtain point cloud data and stitching it together to generate a complete three-dimensional model; S2. Identifying the compressor type and features, the features including: if the type is a cylindrical compressor, then feature A: copper nozzle, feature C: weld, feature D: support leg; if the type is an elliptical compressor, then feature F: weld; S3. Dynamically generating cutting paths based on feature positions: (1) If it is a cylindrical compressor: generating 3 ring paths: upper ring: offset distance d1 based on the boundary of feature C; middle ring: offset distance d2 based on the upper boundary of feature A; lower ring: offset distance d3 based on the highest point of feature D; (2) If it is an elliptical compressor: offset distance d5 upward based on feature F to generate a closed-loop elliptical ring path; S4. Sending the cutting path data to the cutting robot to perform the cutting operation.

[0016] In one embodiment of the present invention, in step S1, after the visual scan is completed, the system automatically verifies the integrity of the point cloud stitching. If the point cloud missing rate is >5%, a rescan is triggered.

[0017] In one embodiment of the present invention, step S2, identifying the compressor type and features, specifically involves: registering the complete three-dimensional point cloud with a pre-stored standard compressor model, and mapping and outputting the compressor's feature type and three-dimensional coordinates based on the registration result and the pre-annotated feature position information in the standard compressor model.

[0018] In one embodiment of the present invention, in step S3, after the three annular paths, the cutting path of the cylindrical compressor further includes five busbar paths: two short busbars: offset by a distance d4 along the two sides of feature A; two medium busbars: extending outward at equal intervals along the short busbar paths; and one long busbar: extending along the center line of the two medium busbars.

[0019] In one embodiment of the present invention, if the type is a cylindrical compressor in step S2, the following features are also included: feature B: bracket, feature E: oil drain hole.

[0020] In one embodiment of the present invention, in step S3, the oil drain hole of the cylindrical compressor should be distributed in the area inside the cutting path close to feature B and feature A or B. If the oil drain hole is located within the busbar path, the busbar path is divided and bypasses the oil drain hole area to avoid the cutting path passing through the oil drain hole area and causing cutting failure.

[0021] In one embodiment of the present invention, the specific steps of bypassing the drain hole area include: identifying the edge contour of the drain hole; generating an avoidance boundary by offsetting outward by a preset safety distance based on the contour; calculating the intersection point with the avoidance boundary on the original busbar path; generating a smooth alternative path from the inlet intersection point to the outlet intersection point, traveling along the avoidance boundary; and splicing the alternative path with the unaffected segment of the original path to form a continuous, collision-free, complete cutting trajectory.

[0022] In one embodiment of the present invention, in step S3, if it is detected that the height of the cylindrical compressor support leg exceeds the threshold H, the lower ring path is dynamically raised to avoid the highest point; wherein, the threshold H < the height of the middle ring - the height of the lower ring.

[0023] In one embodiment of the present invention, the offset distances d1-d5 are dynamically configured according to a compressor model library, which contains historical data on the dimensional tolerance ranges and characteristic positions of cylindrical / elliptical compressors.

[0024] Secondly, the present invention provides a cutting path planning system for implementing the method described above, comprising: a vision acquisition unit with a 3D camera mounted on a rotating imaging mechanism above the loading station for acquiring compressor point cloud data; a data processing unit connected to the vision acquisition unit, comprising an industrial control computer that runs a point cloud stitching algorithm and a path planning module, and outputs compressor type identifiers and geometric feature parameters; a path generation unit connected to the data processing unit that receives the output information from the data processing unit, dynamically calls differentiated path templates according to the compressor type, and generates six-degree-of-freedom trajectory data, wherein the path templates include: a three-ring five-busbar path template for a cylindrical compressor and a single elliptical ring path template for an elliptical compressor; and a communication unit that sends path coordinate data to the cutting robot via the TCP / IP protocol.

[0025] In one embodiment of the present invention, the working distance of the camera of the visual acquisition unit is 600mm±120mm, the field of view is 470mm×330mm@420mm to 751mm×600mm@780mm, and the scanning frequency matches the robot's movement rhythm.

[0026] In one embodiment of the present invention, the system further includes an obstacle avoidance module, which generates a local path correction command when the point cloud detects that the support leg is raised or the oil drain hole is located on the cutting trajectory.

[0027] In one embodiment of the present invention, the system operating status is synchronized to the PLC controller in real time, and the communication protocol includes Modbus TCP or TCP / IP communication protocol.

[0028] In summary, the present invention provides an automatic cutting device for compressor liquid storage tanks, and the beneficial effects of the present invention are:

[0029] This invention places a single compressor on a tooling table and uses a 3D camera mounted on a rotating imaging mechanism above the loading station to take multiple pictures of the compressor. After point cloud stitching, a cutting path is planned. The compressor workpiece is transported to the cutting robot's station via a conveyor line, where the robot, carrying a plasma cutting torch, cuts the compressor. Through a three-tiered mechanism of single-scan modeling, real-time path planning, and continuous cutting execution, the optimal cutting path for two types of compressors is determined. The core advantages are:

[0030] I. High-precision adaptive planning

[0031] A complete point cloud model requires a complete rotation scan by the visual camera to stitch together. The time taken for a cylindrical compressor is ≤18s; the time taken for an elliptical compressor is ≤16s; the positioning accuracy is ±3mm in the xyz direction. It is highly adaptable: compatible with both cylindrical and elliptical compressors, dynamically adapting to dimensional fluctuations and deformations without requiring manual adjustment.

[0032] Simultaneous application of triple constraint mechanism:

[0033] (1) Intelligent obstacle avoidance protection for protruding tank structure, with physical obstacle avoidance distance of copper nozzle / bracket ≥5mm;

[0034] (2) Compatible with structural differences, supporting cylindrical curvature radius R48~95mm, height 150~398mm / ellipse major-to-diameter ratio 0.6-1.4;

[0035] (3) Dynamic deformation compensation, adaptive size fluctuation ±25mm, warping deformation ≤21mm.

[0036] II. Security Protection Upgrade

[0037] Zero-contact operation: Operators are physically isolated from the plasma cutting area, eliminating 100% of work-related accidents;

[0038] Environmental benefits and efficiency: Centralized dust collection improves collection efficiency, reduces waste residue, and decreases emissions.

[0039] Health protection: By cutting off direct contact between personnel and harmful environments, occupational health risks are significantly reduced;

[0040] III. Comprehensive Performance Breakthrough

[0041] Efficiency optimization: Automated processes replace manual labor, reducing the cutting time of a single compressor and supporting continuous production;

[0042] Intelligent upgrade: Intelligent autonomous obstacle avoidance of protrusions on the compressor tank surface increases the tank cutting success rate to 99.5%;

[0043] Economic benefits: Using laser cutting reduces the material loss (copper and tank iron) caused by plasma and other cutting methods, thus increasing the economic value of dismantling. Attached Figure Description

[0044] Figure 1 is a front view of the cutting path of a cylindrical compressor.

[0045] Figure 2 is a right view of the cutting path of the cylindrical compressor.

[0046] Figure 3 is a rear view of the cutting path of the cylindrical compressor.

[0047] Figure 4 is a three-dimensional structural diagram of the cutting path of the elliptical compressor.

[0048] Description of main elements:

[0049] 11. Feature A; 12. Feature B; 13. Feature C; 14. Feature D; 15. Feature E; 16. Feature F; 21. Path 1; 22. Path 2; 23. Path 3; 24. Path 4; 25. Path 5; 26. Path 6; 27. Path 7. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to represent selected embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] Example 1

[0052] This invention relates to the disassembly of compressors for household appliances such as air conditioners and refrigerators. The cutting path planning method for intelligent compressor disassembly involves two major categories of compressor products: cylindrical compressors and elliptical compressors. The model switching between these two categories can be communicated to the vision system in advance (i.e., no material mixing during continuous production). However, the structural form of each category of compressors is the same, but the size specifications and degree of deformation are uncertain. The vision system is compatible with materials within the specified feature range.

[0053] This invention targets cylindrical and elliptical compressors, achieving optimal adaptation of the cutting path through visual point cloud stitching and dynamic path planning. The cutting path planning method for intelligent disassembly of home appliance compressors includes the following steps:

[0054] S1. The compressor on the tooling table is scanned from multiple perspectives using an arm-mounted 3D vision camera to obtain point cloud data and stitch it together to generate a complete 3D model.

[0055] Furthermore, in step S1, after the visual scan is completed, the system automatically verifies the integrity of the point cloud stitching. If the point cloud missing rate is greater than 5%, a rescan is triggered.

[0056] Furthermore, in step S1, the vision system stitches together point clouds by taking multiple photos to identify the actual size and deformation of the workpiece in real time (such as the bending of a column or the ellipticity of a ring), and dynamically adjusts the path coordinates to ensure that the trajectory fits the real contour.

[0057] S2. Identify the compressor type and characteristics. If the type is a cylindrical compressor, then characteristic A11: copper nozzle, characteristic B12: bracket, characteristic C13: weld, characteristic D14: support leg; characteristic E15: oil drain hole. If the type is an elliptical compressor, then characteristic F16: weld.

[0058] Specifically, the feature recognition step (S2) includes: preprocessing the stitched complete 3D point cloud, including downsampling, denoising, and normal estimation; then, feature extraction based on the geometric and topological characteristics of the point cloud. The system maintains a feature template library containing standard 3D models of typical compressors (cylindrical and elliptical) and prior knowledge of feature positions. During recognition, the real-time scanned point cloud is coarsely and finely registered with the models in the template library, and alignment is achieved through algorithms such as Iterative Closest Point (ICP). Then, based on the aligned transformation matrix, the feature positions on the standard model are mapped onto the real-time point cloud to complete the localization and classification of features A, B, C, D, E, and F.

[0059] Through the aforementioned feature recognition technology based on geometric features and template matching, the system can identify and locate workpieces without relying on their absolute size and slight deformation, but only on their stable structural features. This significantly improves the generalization recognition capability and positioning robustness for different brands, models, and used compressors that have undergone wear or transportation deformation, laying a reliable data foundation for subsequent high-precision dynamic path planning.

[0060] S3. Dynamically generate cutting paths based on feature locations:

[0061] S31. If it is a cylindrical compressor:

[0062] Generate 3 circular paths: Upper circular path: offset distance d1 based on the boundary of feature C13, as shown in path 3 23 of Figure 2; Middle circular path: offset distance d2 based on the upper boundary of feature A11, as shown in path 2 22 of Figure 2; Lower circular path: offset distance d3 based on the highest point of feature D14, as shown in path 1 21 of Figure 1.

[0063] Generate 5 bus paths: two short bus paths: offset by a distance d4 along the two sides of feature A11, as shown in path 424 in Figure 1; two medium bus paths: equidistantly extended along the short bus paths, as shown in path 525 in Figure 3; and one long bus path: extended along the center line of the two medium bus paths, as shown in path 626 in Figure 3.

[0064] Specifically, (1) the ring path (path 1 21, path 2 22, path 3 23) is distributed along the ring structure of the outer shell and path 3 23 avoids feature C, so that the upper and lower end caps and the column are accurately separated;

[0065] (2) The busbar paths (path 4 24, path 5 25, path 6 26) extend longitudinally along the column, avoiding key recyclable components such as feature A, feature B, feature D, and feature E;

[0066] (3) The cutting sequence should be circumferential first and then longitudinal to avoid structural instability.

[0067] In step S3, the oil drain holes of the cylindrical compressor should be distributed in the area inside the cutting path near the middle of feature B and feature A or B. If the oil drain hole is located within the busbar path, the busbar path is split and bypasses the oil drain hole area to avoid the cutting path passing through the oil drain hole area and causing cutting failure.

[0068] Furthermore, when the path generation unit detects that the busbar path passes through the drain hole area, it triggers local path correction. The correction algorithm generates a closed polygonal bypass path (e.g., a rectangle or octagon) or a pair of tangent circular arc paths, using the drain hole edge point cloud as the boundary, ensuring that the cutting trajectory maintains a preset safe distance (e.g., ≥3mm) from the drain hole edge. This locally corrected path will replace the line segments that were crossed in the original path.

[0069] Furthermore, the connection points between the local detour path and the original bus path are processed by inserting transition curves or using tangential continuity geometric constraints to ensure that the robot end effector (plasma cutting gun) moves smoothly at the connection points, with continuous speed and direction without abrupt changes, thereby avoiding pauses, jitters or trajectory deviations during the cutting process and ensuring the quality of the cut surface.

[0070] The system dynamically calculates the parameters of the detour path based on the actual size and shape of the drain hole (derived from point cloud recognition). For example, for a circular drain hole, a semi-circular or arc-shaped avoidance path is generated with the hole center as the center and (hole radius + safety margin) as the radius; for irregularly shaped pits, a polygonal avoidance channel is generated based on its point cloud convex hull or minimum bounding rectangle. The safety margin can be retrieved from the process database based on cutting process parameters (such as plasma arc radius and heat-affected zone).

[0071] Through the aforementioned intelligent local detour algorithm, the system can avoid unexpected geometric features such as holes and depressions on the surface of the tank in real time and with precision without interrupting the overall cutting process. This not only avoids the risk of collision between the cutting tool and the workpiece, but also prevents problems such as cutting gas leakage, arc instability, and reduced cutting quality caused by the cutting path passing through holes. It minimizes the dependence of the cutting process on the original structure of the workpiece surface and further improves the system's adaptability and reliability.

[0072] In step S3, if it is detected that the height of the cylindrical compressor support leg exceeds the threshold H, the lower ring path is dynamically raised to avoid the highest point; wherein, the threshold H < the height of the middle ring - the height of the lower ring.

[0073] Furthermore, the threshold H is a configurable parameter preset based on the robot tool radius, system positioning accuracy, and process safety requirements. The specific value of the threshold H is determined by the following formula: H = (Height of the middle ring - Height of the lower ring) - S, where S is the system safety margin. The safety margin S must be set no less than the sum of the robot end effector's (plasma cutting gun) tool radius, the expected maximum deviation of path tracking, and the necessary thermal impact buffer distance. This ensures that, in extreme cases, there is still reliable physical isolation between the raised lower ring path and the middle ring path, eliminating any collision risk.

[0074] Through the aforementioned mechanism of dynamically calculating the threshold H based on geometric space and safety margin, the system can intelligently determine when path intervention is needed and make the minimum necessary path adjustments while ensuring absolute safety. This avoids unnecessary conservative overall lifting of all workpieces and eliminates equipment collisions or process failures caused by imperfect avoidance logic, achieving an optimal balance between safety and efficiency.

[0075] S32. If it is an elliptical compressor: Generate a closed-loop elliptical path by offsetting upwards by a distance d5 from feature F16.

[0076] Path 7.27 (elliptical ring path) is planned along the outside of feature F, visually locating the weld position and adapting to the size changes of the elliptical contour to ensure the gradual separation of the structure; a single ring path covers the separation requirements of the elliptical end cap and the cylinder, simplifying the trajectory while ensuring the integrity of the cutting.

[0077] Furthermore, in step S3, the offset distances d1, d2, d3, d4, and d5 are dynamically configured according to the compressor model library, which contains historical data on the dimensional tolerance range and feature positions of cylindrical / elliptical compressors.

[0078] S4. Send the cutting path data to the cutting robot to perform the cutting operation.

[0079] The core design goals of both types of paths are unified: intelligent obstacle avoidance of protrusions on the compressor tank surface, adaptation to structural differences, and compatibility with dimensional deformation. Through visual guidance technology, the system can achieve precise one-time planning and dynamically adapt to the compressor's shape, generating a continuous and efficient cutting trajectory, thereby significantly improving disassembly efficiency. Compared to traditional methods that rely on human experience or use fixed preset trajectories, the path scheme of this invention has significant advantages in both accuracy and efficiency, thus constituting the optimal and reasonable cutting solution.

[0080] The optimality of the cutting path in this invention is ensured by the following three technical logics: data-driven, feature avoidance, and contour fitting.

[0081] The proprietary path generation logic of this invention is designed separately for cylindrical and elliptical compressor structures:

[0082] (1) Cylindrical compressor: It adopts a composite design of circular trajectory and busbar trajectory to simultaneously meet the key requirements of end cover separation (dependent on circular trajectory) and cylinder disassembly (dependent on busbar trajectory);

[0083] (2) Elliptical compressor: The refining design is a single elliptical ring trajectory, which simplifies the operation path while ensuring the integrity of the cutting process.

[0084] Tests showed that the method in Example 1 was used to disassemble 100 compressors of different models with varying degrees of deformation, achieving a cutting success rate of 99.5%, while the original fixed trajectory method only achieved a success rate of 85%.

[0085] The average cutting path planning time for a single compressor is ≤20 seconds, which is 300% more efficient than manual identification and planning.

[0086] For workpieces with legs warped by 10mm, the system automatically adjusts the path, achieving a 100% obstacle avoidance rate.

[0087] Example 2

[0088] If only the end cap needs to be separated (to recover the internal motor), the busbar path can be omitted, and only the three circular trajectories of the lower, middle, and upper rings can be retained for simplification. This will cause the path planning module to disable the busbar path generation logic, and the cylinder will remain intact after cutting (requiring subsequent crushing). The plasma cutter will only move along the ring (without longitudinal movement), and the cutting parameters will be fixed. This can reduce the trajectory length by 40%, improve the single-unit cutting time, reduce the plasma arc working time, and reduce gas / electricity consumption. The above simplified scenario is used for coarse dismantling scenarios (such as quickly separating the end cap in a scrap yard, followed by uniform crushing of the cylinder).

[0089] Example 3

[0090] The intelligent disassembly and cutting path planning system for home appliance compressors includes: a vision acquisition unit, which uses a 3D camera mounted on a rotating imaging mechanism above the loading station to acquire compressor point cloud data; a data processing unit, connected to the vision acquisition unit, which includes an industrial control computer that runs point cloud stitching algorithms and path planning modules, and outputs compressor type identification and geometric feature parameters; a path generation unit, connected to the data processing unit, which receives the output information from the data processing unit, dynamically calls differentiated path templates according to the compressor type, and generates six-degree-of-freedom trajectory data, wherein the path templates include: a three-ring five-busbar path template for cylindrical compressors and a single elliptical ring path template for elliptical compressors; and a communication unit, which sends path coordinate data to the cutting robot via TCP / IP protocol.

[0091] Furthermore, the camera working distance of the visual acquisition unit is 600mm±120mm, the field of view range is 470mm×330mm@420mm to 751mm×600mm@780mm, and the scanning frequency matches the robot's movement rhythm.

[0092] Furthermore, the operating status of the cutting path planning system is synchronized to the PLC controller in real time, and the communication protocol includes Modbus TCP or TCP / IP communication protocol.

[0093] Furthermore, the cutting path planning system also includes an obstacle avoidance module, which generates a local path correction command when the point cloud detects that the support leg is raised or the oil drain hole is located on the cutting trajectory.

[0094] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A cutting path planning method for intelligent disassembly of a home appliance compressor, characterized in that, Includes the following steps: S1. The compressor on the tooling table is scanned from multiple perspectives using an arm-mounted 3D vision camera to obtain point cloud data and stitch it together to generate a complete 3D model. S2. Identify the compressor type and features, the features include: if the type is a cylindrical compressor, then feature A: copper nozzle, feature C: weld, feature D: support leg; if the type is an elliptical compressor, then feature F: weld; S3. Dynamically generate cutting paths based on feature positions: (1) If it is a cylindrical compressor: generate 3 ring paths: upper ring: offset distance d1 based on the boundary of feature C; middle ring: offset distance d2 based on the upper boundary of feature A; lower ring: offset distance d3 based on the highest point of feature D; (2) If it is an elliptical compressor: generate a closed-loop elliptical ring path by offset distance d5 upward based on feature F; S4. Send the cutting path data to the cutting robot to perform the cutting operation.

2. The method as described in claim 1, characterized in that: In step S1, after the visual scan is completed, the system automatically verifies the integrity of the point cloud stitching. If the point cloud missing rate is greater than 5%, a rescan is triggered.

3. The method as described in claim 1, characterized in that: In step S3, after the three annular paths, the cutting path of the cylindrical compressor also includes five busbar paths: two short busbars: offset by a distance d4 along the two sides of feature A; two medium busbars: extending outward at equal intervals along the short busbar paths; and one long busbar: extending along the center line of the two medium busbars.

4. The method as described in claim 1, characterized in that: In step S2, if the type is a cylindrical compressor, the following features are also included: Feature B: bracket, Feature E: oil drain hole.

5. The method as described in claim 4, characterized in that: In step S3, the oil drain holes of the cylindrical compressor should be distributed in the area inside the cutting path close to feature B and feature A or B. If the oil drain holes are located within the busbar path, the busbar path is divided and bypasses the oil drain hole area to avoid the cutting path passing through the oil drain hole area and causing cutting failure.

6. The method as described in claim 5, characterized in that: The specific steps for bypassing the drain hole area include: identifying the edge contour of the drain hole; using the contour as a reference, offsetting outward by a preset safety distance to generate an avoidance boundary; calculating the intersection point with the avoidance boundary on the original busbar path; generating a smooth alternative path from the inlet intersection point to the outlet intersection point, traveling along the avoidance boundary; and splicing the alternative path with the unaffected segment of the original path to form a continuous, collision-free, complete cutting trajectory.

7. The method as described in claim 1, characterized in that: In step S3, if it is detected that the height of the cylindrical compressor support leg exceeds the threshold H, the lower ring path is dynamically raised to avoid the highest point; where the threshold H < the height of the middle ring - the height of the lower ring.

8. The method as described in claim 1, characterized in that: The offset distances d1-d5 are dynamically configured according to the compressor model library, which contains historical data on the dimensional tolerance range and feature positions of cylindrical / elliptical compressors.

9. A cutting path planning system for intelligent disassembly of a home appliance compressor implementing the method described in any one of claims 1 to 8, characterized in that, include: The vision acquisition unit, which is a 3D camera mounted on a rotating imaging mechanism above the loading station, is used to acquire point cloud data of the compressor. The data processing unit is connected to the vision acquisition unit. The data processing unit includes an industrial control computer, runs a point cloud stitching algorithm and a path planning module, and outputs compressor type identification and geometric feature parameters. The path generation unit, connected to the data processing unit, receives the output information from the data processing unit and dynamically calls differentiated path templates according to the compressor type to generate six-degree-of-freedom trajectory data. The path templates include: a three-ring, five-busbar path template for a cylindrical compressor and a single elliptical ring path template for an elliptical compressor. The communication unit sends path coordinate data to the cutting robot via the TCP / IP protocol.

10. The system as described in claim 9, characterized in that: It also includes an obstacle avoidance module, which generates a local path correction command when the point cloud detects that the support leg is raised or the oil drain hole is located on the cutting trajectory.

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