CN-121997601-A - Non-rigid matching-based blade repair path conformal compensation method and device

CN121997601ACN 121997601 ACN121997601 ACN 121997601ACN-121997601-A

Abstract

The invention belongs to the technical field related to aeroengine manufacturing and precise repair, and discloses a non-rigid matching-based blade repair path conformal compensation method and equipment, wherein the method comprises the following steps of S1, based on a scanning data point set The method comprises the steps of (1) reconstructing a processing error reference point cloud curved surface by a repair area design model, (S2) uniformly modeling the static deviation of the processing error of a blade to be compensated to obtain an error transfer model, simplifying the corresponding nonlinear comprehensive processing error into a calculation equation of the linear pose deviation of a local workpiece coordinate system, S3, establishing a tangent point approximation cost function based on non-rigid matching to register an approximation target curved surface under the constraint of retaining tool path characteristics, and solving the calculation equation by a least square method to obtain the linear pose deviation of the local workpiece coordinate system, solving the pose deviation of each tangent point coordinate system, updating each tangent point and tool position point, and realizing conformal compensation of the blade. The invention improves the compensation precision.

Inventors

HUANG TAO
WU DONGLIANG
SUN CHENCHENG
ZHANG XIAOMING
DING HAN

Assignees

华中科技大学

Dates

Publication Date: 20260508
Application Date: 20260128

Claims (10)

1. A non-rigid matching-based blade repair path conformal compensation method is characterized by comprising the following steps: S1, adopting a non-rigid ICP point cloud registration algorithm, and based on a scanning data point set Reconstructing a processing error reference point cloud curved surface by using the repair area design model; S2, uniformly modeling the static deviation of the machining error of the blade to be compensated based on the machining error reference point cloud curved surface to obtain an error transfer model; s3, establishing a tangent point approximation cost function based on non-rigid matching, registering an approximation target curved surface under the constraint of retaining tool path characteristics by adopting the tangent point approximation cost function, solving a calculation equation by adopting a least square method to obtain the linear pose deviation of the current local workpiece coordinate system, solving the pose deviation of each tangent point coordinate system based on the linear pose deviation of the current local workpiece coordinate system, updating each tangent point and tool position point based on the obtained pose deviation, and realizing shape following compensation of the blade.
2. A non-rigid matching based blade repair path conformal compensation method according to claim 1, wherein the scan data point set is And design model data point set And registering to obtain the machining error reference point cloud curved surface.
3. A non-rigid matching-based blade repair path conformal compensation method as claimed in claim 2, wherein the design model data point set And obtaining by adopting a curvature-based density self-adaptive sampling method.
4. A non-rigid matching based blade repair path conformal compensation method according to claim 1, wherein for each discrete point location Respectively establishing a tangential contact point coordinate system To Represents the theoretical machining point position, In the actual contact point position In the coordinate system, the comprehensive processing error is defined based on the point-tangent plane Expressed as: in the formula, To cut contacts Machining errors in the normal direction.
5. The method for compensating for the shape of a blade repair path based on non-rigid matching as set forth in claim 4, wherein the local workpiece coordinate system pose bias Simultaneously cutting off pose deviation of contact point position coordinate system Satisfying speed-dependent transformation for cut contacts Its position in the object coordinate system is The overall machining error is derived as: in the formula, Is the position error of the local workpiece coordinate system; Is the attitude error of a local workpiece coordinate system; is a coordinate system Position error; is a coordinate system Posture error; is a coordinate system A kind of electronic device A unit vector of the axis in the local workpiece coordinate system; To cut contacts Coordinates in the local object coordinate system.
6. The method for compensating for the shape of a blade repair path based on non-rigid matching as set forth in claim 5, wherein the local workpiece coordinate system pose bias Pose deviation of tangential contact coordinate system There is a relationship between: 。
7. The non-rigid matching-based blade repair path conformal compensation method of any one of claims 1-6, wherein a solving process is realized based on nearest neighbor iteration, the accuracy of the tangential contact correspondence is improved by registering characteristics of the tangential contact and a target curved surface, and the following tangential contact approximation cost function is established to solve the local workpiece pose change: in the formula, Representing the approximation of measurement error and theoretical error, and constructing rigid term The distribution characteristics of the cutting contact points are maintained, Constraint is continuously changed for the pose among all processing sites, wherein, In the formula, Is the non-linear integrated processing error, and the non-linear integrated processing error is the non-linear integrated processing error, The actual measurement processing error is obtained through nearest neighbor search calculation; is the total number of discrete cutting points; To cut contacts The pose deviation of the local workpiece coordinate system corresponding to other tangential point positions in the neighborhood; is the Frobenius norm operator.
8. The method for compensating for the conformal shape of the repair path of the blade based on non-rigid matching as set forth in claim 7, wherein the rigid weight term is used in the repeated iterative convergence process The attenuation is gradual with the change of the iteration number.
9. A non-rigid matching-based blade repair path conformal compensation system is characterized by comprising a memory and a processor, wherein the memory stores a computer program, and the processor executes the non-rigid matching-based blade repair path conformal compensation method according to any one of claims 1-8 when executing the computer program.
10. A computer readable storage medium storing machine executable instructions which when invoked and executed by a processor cause the processor to implement the non-rigid matching based blade repair path shape compensation method of any one of claims 1-8.

Description

Non-rigid matching-based blade repair path conformal compensation method and device Technical Field The invention belongs to the technical field related to aeroengine manufacturing and precise repair, and particularly relates to a non-rigid matching-based blade repair path conformal compensation method and equipment. Background The aeroengine is used as a heart of an aircraft, is a core part and a power source of the aircraft, and the performance of the aeroengine directly affects the safety and the economy of the aircraft. The vane parts are used in the aero-engine on a large scale, the object of the research is a blisk, and compared with the traditional vane turbine disk structure commonly used in the aero-engine, the blisk integrated design is compact in structure, higher in strength and capable of bearing higher rotating speed and working temperature, and the reliability, safety, air tightness and the like of the blisk are remarkably improved. With the progress of aero-engine technology, blisks are used more widely and are commonly used in key parts such as compressors, turbines, fans and the like of aero-engines. Turbine blades and fan blades are subject to various forms of damage, such as cracking, wear, corrosion, breakage, etc., during service, operating in harsh environments at high temperatures, pressures, and speeds for long periods of time. These injuries not only reduce the performance of the engine, but may also cause serious safety accidents. The blade is expensive, for example, the high-pressure turbine blade is more than 10 ten thousand per blade, the integral blade disc is integrally processed, the blade cannot be singly replaced, and the direct replacement of the blade disc is high in economic cost. Therefore, research and development of an effective blade repairing technology of the blade disc have important significance for reducing the maintenance cost of the blade disc and improving the service performance of the blade disc. How to realize the self-adaptive processing quality control of blade repair in high-end equipment such as aeroengines and the like has become one of the core hot problems of research and engineering application in advanced manufacturing fields in recent years. After the blade is repaired in the defect area by the additive manufacturing technology, the subsequent treatment is carried out by adopting material reduction processing technologies such as numerical control milling, precise grinding and polishing and the like, so that the geometric shape and the surface precision of the repaired area can meet the severe engineering standards of key equipment such as aeroengines and the like. For repairing complex components such as blisks, the nature of the repair is a typical reverse engineering task, and due to high-temperature creep and fatigue damage in the service process or the loss of reference information such as an original design drawing, a three-dimensional model and the like, obvious deviation exists between the actual appearance of the blisks and the theoretical design state, and the deviation is often mutually coupled with the reference positioning deviation, so that the high-precision repair requirement is difficult to meet in the traditional positioning machining mode based on a fixed tool and a preset program. In the current blade repairing process, an on-machine measurement-cutting depth direction allowance compensation repairing and compensating scheme is commonly adopted in the industry, a cutter position point is shifted towards the cutting depth direction to compensate for comprehensive processing errors, but nonlinear deviation exists between an actual target curved surface and a theoretical model due to the fact that deformation, reference deviation and the like exist on an actual shape surface of a blade, an accurate corresponding relation of a cutting contact point is difficult to establish in a to-be-repaired area through traditional cutting depth or normal vector direction compensating and mapping, problems of deviation of a processing streamline, undercutting or overcutting of a blade edge area and the like are easily caused, and geometric accuracy and aerodynamic performance after the blade repairing is seriously affected. Disclosure of Invention Aiming at the defects or improvement demands of the prior art, the invention provides a non-rigid matching-based blade repair path conformal compensation method and equipment, which aim to solve the problem of low compensation precision of the existing blade. In order to achieve the above object, according to one aspect of the present invention, there is provided a method for compensating for a shape of a repair path of a blade based on non-rigid matching, comprising the steps of: S1, adopting a non-rigid ICP point cloud registration algorithm, and based on a scanning data point set Reconstructing a processing error reference point cloud curved surface by using the repair area design model; S2, unifo