Integral impeller measurement path planning method and device, electronic equipment and storage medium

Abstract

This application discloses a method, device, electronic equipment, and storage medium for overall impeller measurement path planning. This scheme belongs to the field of on-machine measurement technology for CNC machine tools. Specifically, it first performs adaptive distribution processing of the measurement points on the surface to be measured. Based on the local surface normal constraints of the measurement points, the machine tool rotation axis angle limit constraints, and the table anti-collision constraints, it performs a rough screening of attitude rays to obtain a rough screening attitude ray set. A projection line is selected and projected onto the surface to be measured along the surface normal. Based on the projection boundary line, the global measurement points of the impeller are adaptively divided into an unobstructed open area and a flow channel restricted area. For the measurement points in the open area, a non-interference fine screening attitude set is obtained; after completing the attitude pre-screening for the measurement points in the restricted area, a global ray-model bounded intersection detection is performed in conjunction with the impeller model to obtain a collision-free reachable attitude set. The two types of attitude sets are integrated to perform global path optimization, outputting the measurement point execution sequence and probe attitude data. Implementation verification shows that this scheme, by using partitioned differentiated screening, reduces redundant calculations and can significantly avoid wasting computing power.

Description

Technical Field

[0001] This application relates to the field of in-machine measurement technology for CNC machine tools, and more specifically, to a method, apparatus, electronic device, and storage medium for overall impeller measurement path planning. Background Technology

[0002] As a core component of hydroelectric generator sets, the turbine runner's blades are typically precision parts composed of complex three-dimensional twisted free-form surfaces. With modern hydroelectric power stations developing towards larger capacity and higher efficiency, the machining accuracy requirements for runner blades are becoming increasingly stringent. Any minute geometric deviation in the blade surface can trigger cavitation, vibration, and energy loss in high-speed water flow, thus affecting the long-term safe and stable operation of the entire unit. Therefore, timely acquisition of the actual geometric accuracy of the blades during critical CNC machining processes has become a crucial step in controlling machining quality and avoiding ineffective cutting. Compared to coordinate measuring machines (CMMs), which require disassembling the workpiece from the machine tool and transporting it to offline measuring equipment, in-machine measurement directly utilizes the machine tool itself or an integrated probe to complete the inspection at the machining station. This not only saves time spent on repeated clamping but also allows for timely detection of machining deviations and feedback to subsequent toolpath corrections, without causing secondary clamping errors. Therefore, it has gained increasing attention in the intelligent manufacturing of complex curved surface parts.

[0003] However, when in-machine measurement technology is applied to parts such as pump turbine runners, it encounters unique difficulties not present in general components. Runners typically consist of an upper crown, a lower ring, and six to nine circumferentially distributed twisted blades, such as... Figure 1 As shown, the wrap angle of each blade relative to the rotor axis often exceeds 90 degrees, forming a narrow flow channel with radially varying depth between adjacent blades. The curvature of the blade surface changes drastically at different radii; the closer to the rotor axis, the larger the angle between the blade and the circumferential tangent, and the narrower the flow channel space. This means that when the probe penetrates deep into the flow channel for contact testing, its attitude space is severely compressed by the high-pressure and low-pressure surfaces of adjacent blades, resulting in extremely limited feasible probe directions. Finding collision-free probe attitudes for hundreds or thousands of measurement points within such a confined space, while ensuring that the probe does not interfere with the surrounding structure during movement, undoubtedly presents a significant challenge to measurement path planning.

[0004] Currently, the mainstream approach to solving the reachable attitude of a probe at a measuring point on a turbine blade is based on the reachability cone theory. Specifically, taking each discrete measuring point on the surface to be measured as the origin, a large number of uniformly distributed candidate directional rays are generated in the surrounding space using a spherical lattice. These rays are then subjected to bounded intersection checks with the overall three-dimensional solid model of the impeller, eliminating rays that collide with the model's geometry. The final set of interference-free rays is the reachability cone for that measuring point. In principle, this method can obtain a theoretically complete solution for the reachable attitude. However, in engineering practice, it faces a serious efficiency bottleneck. Since each ray needs to undergo a solid intersection calculation with the entire impeller model, when the number of measuring points is large and the number of discrete directions at a single point reaches thousands, the overall computational load will rapidly expand to millions of intersection calculations, making the solution time for the reachability cone unacceptable. More importantly, this strategy of indiscriminately traversing all rays does not take into account the spatial structural characteristics of the impeller channel. In fact, the feasible attitude space of measurement points located in the open area of ​​the outer edge of the blade is very different from that of measurement points deep inside the channel. However, the existing method treats the two equally, and a large number of geometrically obviously infeasible rays are still sent into the time-consuming global intersection process, resulting in a significant waste of computing power. Summary of the Invention

[0005] In view of this, this application provides a method, apparatus, electronic device and storage medium for planning the measurement path of an integral impeller during in-machine measurement, so as to avoid wasting computing power.

[0006] To achieve the above objectives, the following solution is proposed: A method for planning the measurement path of an integral impeller, applied to electronic equipment, includes the following steps: Isoparametric curves are constructed for the surface under test, and the distribution of measurement points is adaptively determined based on the NURBS curves and curvature changes. Using the center of the measuring ball at each measuring point as the origin, attitude rays are discretized in space. The attitude rays are coarsely screened using the local surface normal constraint of the measuring point, the machine tool rotation axis angle limit constraint, and the machine tool worktable anti-collision constraint to obtain a coarsely screened attitude ray set. The projection line is selected and projected onto the surface to be measured along the surface normal. Based on the projection boundary line, the global measuring points of the impeller are adaptively divided into an unobstructed open area and a flow channel restricted area. For the measurement points in the unobstructed open area, the coarse screening attitude ray set and the overall impeller model are subjected to global ray-model bounded intersection detection to obtain the open area non-interference fine screening attitude set. For the measuring points in the confined area of ​​the flow channel, a local spatial constraint circle is constructed based on the positional relationship of the outer contour lines of adjacent blades in the local space of the flow channel. The local spatial constraint circle is used to perform geometric analysis pre-screening on the coarse screening attitude ray set, and the rays that interfere with the local spatial constraint circle are removed to obtain the confined area pre-screening attitude ray set. The restricted area pre-screened attitude ray set is subjected to global ray-model bounded intersection detection with the overall impeller model to obtain the restricted area collision-free reachable attitude set. Based on the open area non-interference fine screening attitude set and the restricted area non-collision reachable attitude set, the reachable probe attitude of each measuring point is determined; with the minimum rotation angle of attitude transfer between adjacent measuring points as the constraint condition, the measuring points with reachable probe attitudes are constructed into continuous measurable segments, and global path optimization is performed on each continuous measurable segment to obtain the measuring point execution sequence and probe attitude data.

[0007] Optionally, the step of constructing isoparametric curves for the surface under test and adaptively distributing measurement points based on NURBS curves and curvature changes includes the following steps: Extract the NURBS geometric model information of the impeller surface to be measured, and construct isoparametric curves within the parameter domain; The curvature change rate at each node on the surface is calculated. The sampling density of the measuring points is increased in the high curvature region where the curvature change is drastic, and the sampling density of the measuring points is decreased in the region where the curvature change is gentle, so as to achieve an adaptive discrete distribution of the measuring points on the isoparametric curve.

[0008] Optionally, the process involves using the center of the measuring sphere at each measuring point as the origin to discretize and generate attitude rays in space. These attitude rays are then coarsely screened using local surface normal constraints at the measuring points, machine tool rotation axis angle limit constraints, and machine tool table anti-collision constraints to obtain a coarsely screened attitude ray set. A projection line is selected and projected onto the surface to be measured along the surface normal. Based on the projection boundary line, the global measuring points of the impeller are adaptively divided into an unobstructed open area and a flow channel restricted area. This includes the following steps: Using the Fibonacci spherical lattice method, spherical direction rays are generated in space, starting from the center of each sphere; Using the local surface normal constraint of the measuring point, the machine tool rotation axis angle limit constraint, and the machine tool worktable anti-collision constraint as three criteria, the spherical direction rays are initially screened, and invalid directions that do not meet the above criteria are eliminated to obtain the coarse screening attitude ray set; Select a projection line and project it onto the surface to be measured along the normal of the surface. Extract the projection point set to construct the projection boundary line. By calculating the sign distance and positional relationship between the measurement point and the projection boundary line, the global measurement points are adaptively divided into unobstructed open areas and flow channel restricted areas.

[0009] Optionally, the global ray-model bounded intersection detection calls the ray-surface bounded intersection interface of the geometric kernel to perform collision detection on each attitude ray in the coarse screening attitude ray set and the overall impeller 3D solid model, and retains the attitude rays without collision as the open area non-interference fine screening attitude set.

[0010] Optionally, for the measuring points within the confined flow channel, a local spatial constraint circle is constructed based on the positional relationship of the outer contour lines of adjacent blades in the local space of the flow channel. This local spatial constraint circle is then used to perform geometric analytical pre-screening of the coarse screening attitude ray set, eliminating rays that interfere with the local spatial constraint circle, thus obtaining the confined area pre-screening attitude ray set. This includes the following steps: For any measuring point located in the confined flow channel area, calculate the tangent vector of the measuring point on its isoparametric curve. Draw a spatial perpendicular line to the tangent vector through the measuring point, so that it intersects the outer contour line of the adjacent low-pressure surface at point A. Search for the point B closest to point A on the outer contour line of the adjacent high-pressure surface. Construct the local spatial constraint circle with line segment AB as the diameter and the midpoint O of line segment AB as the center. Set the angle between the normal vector of the circle plane and the vector from the measuring point to point A to be the smallest, so as to ensure that the constraint surface faces outward. Calculate the intersection parameters of the candidate attitude rays in the coarse screening attitude ray set with the local spatial constraint circle, determine that the ray crosses in the positive direction and the intersection point falls within the radius of the local spatial constraint circle, and retain the rays that satisfy the above determination as the restricted area pre-screening attitude ray set.

[0011] Optionally, the step of performing global ray-model bounded intersection detection between the pre-screened attitude ray set of the confined area and the overall impeller model includes: After obtaining the set of collision-free reachable postures in the restricted area, the non-interference rays in the set of collision-free reachable postures in the restricted area are reconstructed with the center of the measuring ball at the corresponding retreat point as the starting point, and a second intersection fine screening is performed. The posture after passing the second intersection fine screening is taken as the final non-interference reachable probe posture of the measuring point in the restricted area of ​​the flow channel.

[0012] Optionally, the global path optimization adopts an adaptive genetic algorithm based on the Tent-Logistic-Cosine chaotic mapping. With the shortest non-measurement movement distance between measurement points as the optimization objective, the algorithm iteratively optimizes the execution sequence of measurement points in each continuous measurable segment to obtain the globally optimal measurement path.

[0013] An integrated impeller measurement path planning device, applied to electronic equipment, the planning device comprising: The measurement point distribution module is configured to construct isoparametric curves for the surface under test and adaptively distribute measurement points based on NURBS curves and curvature changes. The coarse screening and region division module is configured to generate attitude rays in space with the center of the measuring ball at each measuring point as the origin. The attitude rays are coarsely screened using the local surface normal constraint of the measuring point, the machine tool rotation axis angle limit constraint, and the machine tool worktable anti-collision constraint to obtain a coarse screening attitude ray set. The projection line is selected and projected onto the surface to be measured along the surface normal. Based on the projection boundary line, the global measuring points of the impeller are adaptively divided into an unobstructed open area and a flow channel restricted area. The open area fine screening module is configured to perform global ray-model bounded intersection detection on the coarse screening attitude ray set and the overall impeller model for the measurement points in the unobstructed open area, so as to obtain the open area non-interference fine screening attitude set. The restricted area pre-screening module is configured to construct a local spatial constraint circle for the measuring points within the restricted area of ​​the flow channel based on the positional relationship of the outer contour lines of adjacent blades in the local space of the flow channel. The local spatial constraint circle is used to perform geometric analytical pre-screening on the coarse screening attitude ray set, and the rays that interfere with the local spatial constraint circle are removed to obtain the restricted area pre-screening attitude ray set. The restricted area verification module is configured to perform global ray-model bounded intersection detection on the pre-screened attitude ray set of the restricted area and the overall impeller model to obtain a set of collision-free reachable attitudes in the restricted area. The path planning module is configured to determine the reachable probe posture of each measuring point based on the non-interference fine screening posture set in the open area and the non-collision reachable posture set in the restricted area; using the minimum rotation angle of posture transfer between adjacent measuring points as a constraint, measuring points with reachable probe postures are constructed into continuous measurable segments, and global path optimization is performed on each continuous measurable segment to obtain the measuring point execution sequence and probe posture data.

[0014] An electronic device includes at least one processor and a memory connected to the processor, wherein: The memory is used to store computer programs or instructions; The processor is used to execute the computer program or instructions to enable the electronic device to implement the overall impeller measurement path planning method as described above.

[0015] A computer-readable storage medium is applied to an electronic device, the storage medium carrying one or more computer programs, the one or more calculations and programs being executable by the electronic device, thereby enabling the electronic device to implement the overall impeller measurement path planning method as described above.

[0016] As can be seen from the above technical solution, this application discloses a method, device, electronic device, and storage medium for overall impeller measurement path planning. The method and storage medium are applied to the electronic device, specifically: adaptively distributing measurement points on the surface to be measured; using the local surface normal constraint of the measurement points, the machine tool rotation axis angle limit constraint, and the machine tool worktable anti-collision constraint to coarsely screen the attitude rays, obtaining a coarsely screened attitude ray set; selecting projection lines and projecting them onto the surface to be measured along the surface normal, and adaptively dividing the global measurement points of the impeller into an unobstructed open area and a flow channel restricted area based on the projection boundary line; obtaining an interference-free fine screening attitude set for the measurement points in the unobstructed open area; obtaining a pre-screened attitude ray set for the measurement points in the flow channel restricted area; performing a global ray-model bounded intersection detection between the pre-screened attitude ray set in the restricted area and the overall impeller model to obtain a collision-free reachable attitude set in the restricted area; and performing global path optimization based on the interference-free fine screening attitude set in the open area and the collision-free reachable attitude set in the restricted area to obtain the measurement point execution sequence and probe attitude data. Specific implementation shows that this scheme can significantly shorten the computation time for reachable cones, thereby avoiding the waste of computing power. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of an impeller model; Figure 2 This is a flowchart of an overall impeller measurement path planning method according to an embodiment of this application; Figure 3 This is a schematic diagram of criterion one of the embodiments of this application; Figure 4 This is a schematic diagram of criterion two in an embodiment of this application; Figure 5 This is a schematic diagram of criterion three in the embodiments of this application; Figure 6 This is a schematic diagram of the segmented region in an embodiment of this application; Figure 7 This is a schematic diagram of a local spatial constraint circle according to an embodiment of this application; Figure 8 This is a view of the reachability cone calculation results in an embodiment of this application; Figure 9 The optimal path and fitness curve under the GA algorithm in this application are shown. Figure 10The optimal path and fitness curve under the LNS-GA algorithm in this application are shown. Figure 11 The optimal path and fitness curve under the AGA algorithm in this application are shown. Figure 12 The optimal path and fitness curve under the LNS-AGA algorithm in this application are shown. Figure 13 The TLC planning path and fitness curve are shown in the embodiments of this application; Figure 14 This is a block diagram of an integral impeller measurement path planning device according to an embodiment of this application; Figure 15 This is a block diagram of an electronic device according to an embodiment of this application. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0020] Figure 2 This is a flowchart illustrating a method for overall impeller measurement path planning according to an embodiment of this application.

[0021] like Figure 2 As shown, the overall impeller measurement path planning method provided in this embodiment is applied to an electronic device for planning the overall impeller measurement path based on local analytical constraints. This electronic device can be understood as a computer, server, or cloud platform with data computing and information processing capabilities. The overall impeller measurement path planning method specifically includes the following steps: S1. Construct isoparametric curves for the surface to be measured and adaptively distribute the measurement points.

[0022] First, the isoparametric discrete curve method is used to extract characteristic curves from the complex surfaces of the known CAD model, and the spatial geometry of the surface is fully represented by the characteristic curves. NURBS curves are then used to represent the isoparametric curves, and an adaptive distribution of curvature measurement points is implemented based on these curves.

[0023] Let C( u The specific NURBS expression is as follows: , In the formula, Let w be a p-th order B-spline basis function. i P is the weighting factor.i These are control points.

[0024] From the curve expression, the curvature of the NURBS curve at parameter u is calculated as follows: , In the formula, The first derivative of the curve. It is the second derivative.

[0025] In regions with significant curvature variations, the curve exhibits greater curvature and more pronounced changes in local geometric features. To avoid excessively dense measurement points in areas of abrupt curvature changes and excessively sparse measurement points in areas of smooth curvature, the curvature parameters are normalized, and basic sampling weights are introduced: , , In the formula, The curvature parameters after normalization. To select the minimum curvature of the isoparametric curve, To select the maximum curvature of the isoparametric curve, For curvature measurement, Use the base sampling weights.

[0026] Basic sampling weights The value range is [0,1]. Its value can be determined by combining the expected density differences in different regions of the blade. Taking into account the preservation of features in high curvature regions and the sampling integrity in low curvature regions, the initial value is 0.2. Subsequently, it can be adjusted by comparing the measurement point distribution results and curve reconstruction errors under different values.

[0027] By using curvature measure as the curve sampling density index and integrating over the arc length, the total mass of the curve is obtained. The total mass is divided into (N+1) equal-mass regions by the number of target measurement points N. The sampling point parameters are determined by the midpoint sampling criterion of the interval. Therefore, the j-th sampling point satisfies the following expression: , In the formula, Where M is the range of curve parameters and M is the total mass of the curve after weighting by the curvature measure.

[0028] The sampling parameters are thus obtained. u j Then, substitute the coordinates of the measurement point into the NURBS expression above to obtain the corresponding coordinates.

[0029] Through the above process, the measurement points are adaptively discretely distributed on the isoparametric curve, the sampling density in the high curvature region is increased, and the sampling density in the low curvature region is reduced, thereby preserving key geometric features while avoiding excessive density of measurement points.

[0030] S2, Discrete generation of attitude rays, coarse screening and adaptive region partitioning.

[0031] After completing the distribution planning of measurement points on the surface to be measured, the Fibonacci spherical lattice method is introduced to discretize the probe's measurement posture in three-dimensional space, using the center of the sphere at each measurement point as the origin. This method generates a spherical spiral point set based on the golden section angle, and ensures that the discrete sampling vectors are uniformly distributed isotropically on the unit sphere by linearly dividing the longitudinal height coordinate and strictly controlling the circumferential azimuth angle using irrational angle increments. In this embodiment, the initial number of discrete directions in the single-point posture space is set to 2000.

[0032] Subsequently, using the local surface normal constraint of the measuring point, the machine tool rotation axis angle limit constraint, and the machine tool table anti-collision constraint as three criteria, the above spatial discrete rays are initially screened, and invalid directions that do not meet the above criteria are eliminated, resulting in a coarsely screened attitude ray set. Specifically, the three criteria are as follows: Criterion 1: Local surface normal constraint at the measuring point: Based on the principle of "contact measurement in the southern hemisphere," interference from the probe's posture was initially eliminated, and the consistency between the probe's contact area and the calibration state was maintained to support subsequent pre-stroke error compensation. The discrete measurement points on the measured surface S are designated as P. i The unit normal vector at that point is The tangent plane of the surface passing through point P is Let the radius of the measuring sphere be R, and the center of the measuring sphere be located at C. i Introducing the center C of the ball i And parallel to The reference plane is The direction vector of any measuring rod extending outward from the center of the sphere is: .like Figure 3 As shown, A, B, C, and D are examples of valid probe postures that satisfy criterion one. Therefore, criterion one can be given by the following spatial vector set expression: . .

[0033] Guideline 2: Collision Prevention Constraints for Machine Tool Tables Due to the geometric constraints of the workpiece and the physical worktable, the accessibility search range must be strictly limited to the upper half of the space above the worktable. To avoid intrusive interference from the probe's downward movement on the machine tool worktable, the probe must be oriented with an upward vertical component.

[0034] like Figure 4 As shown in the figure, A, B, and C are examples of effective probe postures that satisfy criterion two, passing through the center of the sphere. The horizontal plane and the sphere form a plane Its effective attitude space can be given by the following expression for a set of space vectors: .

[0035] Criterion 3: Limit Constraints on the Angle of Machine Tool Rotary Axes To ensure that the probe's position is within the range of motion of the measuring equipment, the travel limitations of the machine tool's rotary axis must also be considered, such as... Figure 5 As shown in the figure, taking the AC axis as an example, the rotation angle of the C axis is... The rotation angle of axis A is Five-axis machine tools with different configurations (AC-axis, AB-axis, BC-axis) have varying degrees of rotational freedom. Therefore, a unified physical travel constraint model for the machine tool is established here. Let the variables representing the machine tool's rotation angles around the X, Y, and Z axes be... , , Define the rotation axis screening factor as , When the value is 0, the axis has a corresponding rotational constraint. When the value is 1, there is no corresponding rotational constraint for that axis. The rotational constraint space region for each rotational axis is given by its angular range. Let each rotational axis... j The angle range is Therefore, by introducing characteristic multipliers ( Constructing the spatial range of motion of the rotation axis: , For any probe orientation vector After normalization and conversion to a spherical polar coordinate system, the rotation relative to each linear axis is obtained, i.e.: , Therefore, the kinematic constraints of criterion three can be given by the following spatial vector set expression:

[0036] Combining the above three criteria, the coarse screening attitude ray set of the probe posture when it touches the measuring point is obtained. This is given by the following expression: , Since this coarse screening process only involves simple vector operations and angle judgments, it avoids the bounded intersection detection of ray-model, and its time cost is minimal.

[0037] After coarse screening, the global measurement points of the impeller need to be adaptively divided into an unobstructed open area and a confined flow channel area. To this end, the outer contour lines of adjacent blades are selected as projection lines and projected onto the surface to be measured along the surface normal. The projection point set is then extracted to construct the projection boundary line. The construction of this projection boundary mainly utilizes BRep_Tool::Curve() and BRep_Tool::Surface() in OCCT to obtain the geometric representations of the contour lines and the surface to be measured, respectively, and then uses ShapeAnalysis_Surface::ValueOfUV() to map the discrete points of the contour lines to the surface to be measured.

[0038] After the projection boundary line is constructed, the closest position between the measuring point and the boundary line is obtained using GeomAPI_ProjectPointOnCurve, and the local normal of the surface to be measured is calculated using Geom_Surface::D1(). The local segmentation direction is then constructed based on the tangent vector of the projection line and the surface normal. Let the measuring point... The nearest point on the projection boundary line is , The splitting tangent vector of the point on the projection boundary is The normal vector of this point on the blade surface is The partitioning normal vector is The symbolic distance is ,but: , .

[0039] By judgment The sign of the measurement point is used to distinguish its location, such as... Figure 6 As shown, When d > 0, the measuring point is located above the projection boundary, with open space and a very low probability of being blocked by adjacent blades, and is therefore classified as an unobstructed open area. When the value is less than 0, the measuring point is located below the projected boundary and extends deep into the narrow flow channel, thus classifying it as the flow channel confined area. This enables adaptive division of global measuring points, laying the foundation for subsequent differentiated fine screening strategies.

[0040] S3, Open Area Global Ray-Model Bounded Intersection Detection.

[0041] For measurement points in unobstructed open areas, since the space is open and the probability of being blocked by adjacent blades is extremely low, the coarse screening attitude ray set obtained above can be directly subjected to global ray-model bounded intersection detection with the overall impeller model without the need for additional local pre-screening steps.

[0042] In practice, attitude rays are constructed using `gp_Dir` and `gp_Lin`, and the bounded intersection of the rays with the global model `TopoDS_Shape` is performed using OCCT's `BRepIntCurveSurface_Inter`. Collision detection is then performed on each attitude ray in the coarse-screened set, eliminating interfering attitudes and retaining collision-free rays, thus obtaining the open-area interference-free fine-screened attitude set. Since the attitude space of the measurement points in the open area is relatively ample, a large proportion of the coarse-screened rays can already be interfered globally, and the computational load in this region does not constitute a bottleneck.

[0043] S4. Construction and geometric analysis pre-screening of local spatial constraint circles in confined areas.

[0044] For measurement points within the confined flow channel region, the probe attitude space is severely compressed by the high-pressure and low-pressure surfaces of adjacent blades. If a global intersection is directly performed on all coarse-screening attitude rays, many geometrically infeasible rays would still require individual collision detection with the overall impeller model, resulting in significant computational waste. Therefore, this implementation introduces a local spatial constraint circle for geometric analytical pre-screening before global intersection.

[0045] The construction process of a locally constrained circle is as follows: any measuring point located in the confined region of the flow channel... First, calculate the tangent vector T of the measuring point on its isoparametric curve. Draw a spatial perpendicular line from the measuring point P to the tangent vector T, intersecting it at point A on the outer contour of the adjacent low-pressure surface. Then, search for the point B closest to point A on the outer contour of the adjacent high-pressure surface. Construct a local spatial constraint circle with line segment AB as its diameter and its midpoint O as its center, as shown below. Figure 7 As shown. This constraint circle is generated using OCCT's geometry and topology tools such as gp_Ax2, gp_Circ, and BRepBuilderAPI_MakeEdge(), and is used to describe the local window through which the probe can pass within the restricted flow channel.

[0046] When constructing a local spatial constraint circle, the angle between the normal vector of the circle plane and the vector from the measuring point to point A (i.e., vector PA) is set to be the smallest to ensure that the constraint surface faces outward and that the constraint circle correctly defines the local spatial range that the measuring needle can pass through.

[0047] After the local spatial constraint circle is constructed, the candidate attitude rays in the coarse-screened attitude ray set are geometrically pre-screened based on this constraint circle. The intersection parameters of each candidate attitude ray with the local spatial constraint circle are calculated to determine whether the ray crosses in a positive direction and whether the intersection point falls within the radius of the local spatial constraint circle. Only rays that satisfy the above two criteria are retained, and rays that interfere with the constraint circle or whose crossing direction does not meet the requirements are removed, thus obtaining the constrained area pre-screened attitude ray set.

[0048] Through the above-mentioned geometric analysis pre-screening, a large number of candidate poses that are obviously not geometrically feasible in the confined area of ​​the flow channel are eliminated before entering the global intersection calculation, which significantly reduces the number of rays that need to be detected for physical collisions in the future, thereby effectively alleviating the computing power bottleneck in the narrow flow channel area.

[0049] S5. Global intersection verification and secondary screening of backtracking points in the restricted area.

[0050] After the above geometric pre-screening, the number of rays in the confined area pre-screened attitude ray set has been significantly reduced. To ensure the absolute safety of the final detection attitude, a global ray-model bounded intersection test is performed between this confined area pre-screened attitude ray set and the overall impeller model. Then, BRepIntCurveSurface_Inter is called again to perform bounded intersection tests between each pre-screened ray and the overall model TopoDS_Shape, eliminating interfering attitudes and obtaining a collision-free reachable attitude set in the confined area, such as... Figure 8 As shown.

[0051] It is particularly important to note that in flow-restricted areas, after the probe completes a single-point contact measurement, it must retract a safe distance along the probe rod direction before moving to the next measurement point. The spatial position after retraction is different from the original measurement point, especially in flow-restricted areas where the effective space along the retraction path is narrower than at the measurement point. Therefore, verifying no interference at the measurement point contact position alone is insufficient to guarantee the safety of the entire measurement operation.

[0052] Therefore, after obtaining the set of collision-free reachable postures in the confined area, the interference-free rays in this set are moved to the corresponding retraction points for secondary intersection screening. Specifically, using the center of the probe at the retraction point as the new ray starting point, while maintaining the original posture direction, BRepIntCurveSurface_Inter is called again to perform bounded intersection detection. Only postures that pass the secondary intersection screening are retained as the final interference-free reachable probe postures for the flow channel confined area measurement points; postures that fail the secondary verification are removed from the reachable posture set. This mechanism effectively fills the safety blind spot during probe retraction, ensuring that the planned measurement path will not interfere with the actual machine tool execution due to retraction collisions.

[0053] S6. Construction of Continuously Measurable Sections and Global Path Optimization.

[0054] Based on the above operations that yield the interference-free fine screening attitude set in the open area and the collision-free reachable attitude set in the confined area, the reachable probe attitude of each measuring point is first determined. For each measuring point, the optimal attitude from its corresponding attitude set is selected as the reachable probe attitude for that point, thereby establishing a mapping relationship between global measuring points and their reachable attitudes.

[0055] To ensure smooth and continuous movement of the probe within the flow channel and reduce attitude deflection of the multi-axis mechanism, a continuous measurable segment is constructed using the minimum rotation angle of attitude transfer between adjacent measuring points as a constraint. Specifically, the dot product angle of candidate reachable attitude vectors between adjacent measuring points is calculated. When the rotation angle of attitude transfer between adjacent measuring points is less than a set angle tolerance threshold, the adjacent measuring points are merged into the same continuous measurable segment. In this embodiment, the angle tolerance threshold is set to 10°. This continuous measurable segment is constructed by dividing the flow channel. This ensures that the probe's attitude remains consistent or undergoes small, continuous changes within the section, effectively suppressing drastic probe deflection within narrow flow channels. This continuously measurable section... The expression is as follows: , And any adjacent measuring points in this section satisfy the following: , In the formula This represents the angle between the i-th measuring point and the (i+1)-th measuring point. The maximum allowable angle change threshold.

[0056] After the continuous measurable sections are constructed, global path optimization is performed on each continuous measurable section to reduce the non-measuring idle travel of the probe and improve detection efficiency. The starting point of the measurement is determined based on the coordinates of the measurement points. The path optimization mainly focuses on optimizing the non-measuring travel distance between adjacent measurement points from the backtracking point of the previous measurement point to the starting point of the next measurement point, with the shortest total measurement path length as the optimization objective.

[0057] This implementation uses an adaptive genetic algorithm based on the Tent-Logistic-Cosine (TLC) chaotic map for measurement path planning. The TLC chaotic map is expressed as: , In the formula, x n The value represents the chaotic orbital state, and its range is (0,1). μ The parameters are mixed. This chaotic map combines the complex nonlinear characteristics of the cosine transform with the chaotic dynamics advantages of the Tent and Logistic maps, exhibiting excellent ergodicity and nonlinearity.

[0058] The algorithm employs real-number encoding, using the sequence of measurement point numbers as the order of chromosome expression paths. In the initial population generation stage, a large-scale neighborhood search algorithm and a chaotic reversal operator are introduced to improve the quality of the initial solution and population diversity, avoiding the slow convergence problem caused by completely random initialization in traditional genetic algorithms. Subsequently, iterative searches are performed through operations such as fitness calculation, roulette wheel selection, adaptive crossover mutation, and chaotic optimization. Among these, chaotic optimization utilizes the ergodicity and nonlinearity of the Tent-Logistic-Cosine mapping to reverse the order of individual gene segments, retaining individuals with better fitness, thereby enhancing the algorithm's ability to escape local optima.

[0059] In this embodiment, the algorithm parameters are set as follows: population size popSize = 41, maximum number of iterations maxGen = 1000. Through the above genetic iterative optimization, the globally optimal measurement path is obtained, yielding the measurement point execution sequence and probe posture data. Verification has shown that, compared to traditional methods… Figure 9 The GA shown Figure 10 The LNS-GA algorithm shown Figure 11 The AGA algorithm shown and Figure 12 Of the algorithms shown, such as LNS-AGA, the TLC algorithm used in this implementation method yields the shortest measurement path length. Figure 13 As shown, this can effectively shorten the probe's travel distance.

[0060] After obtaining the final measurement point coordinates, probe posture data, and motion paths between measurement points, these data are input into the post-processing equipment. The post-processing equipment transforms the optimized measurement point coordinates and probe optimal posture into the machine tool workpiece coordinate system using matrix transformation, generates a G-code program for actual machine tool measurement, outputs the measurement point execution sequence and probe posture data, and completes the overall impeller in-machine measurement path planning.

[0061] As can be seen from the above technical solution, this application provides a method for overall impeller measurement path planning. This method is applied to electronic equipment, specifically involving the adaptive distribution of measurement points on the surface to be measured; coarse screening of attitude rays using local surface normal constraints of measurement points, machine tool rotation axis angle limit constraints, and machine tool worktable anti-collision constraints to obtain a coarsely screened attitude ray set; selecting projection lines and projecting them onto the surface to be measured along the surface normal, and adaptively dividing the global measurement points of the impeller into an unobstructed open area and a flow channel restricted area based on the projection boundary lines; obtaining a non-interference fine screening attitude set for measurement points in the unobstructed open area; obtaining a pre-screened attitude ray set for measurement points in the flow channel restricted area; performing global ray-model bounded intersection detection between the pre-screened attitude ray set in the restricted area and the overall impeller model to obtain a collision-free reachable attitude set in the restricted area; and performing global path optimization based on the non-interference fine screening attitude set in the open area and the collision-free reachable attitude set in the restricted area to obtain the measurement point execution sequence and probe attitude data. Specific implementation shows that this solution can significantly shorten the computation time of reachable cones, thereby avoiding wasted computing power.

[0062] Although the operations are described in a specific order, this should not be construed as requiring these operations to be performed in the specific order shown or in a sequential order. In certain environments, multitasking and parallel processing may be advantageous.

[0063] It should be understood that the steps described in the method embodiments of this disclosure may be performed in different orders and / or in parallel. Furthermore, the method embodiments may include additional steps and / or omit the steps shown. The scope of this disclosure is not limited in this respect.

[0064] Computer program code for performing the operations of this disclosure can be written in one or more programming languages ​​or a combination thereof, including but not limited to object-oriented programming languages ​​such as Java, Smalltalk, and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer.

[0065] Figure 14 This is a block diagram of an overall impeller measurement path planning device according to an embodiment of this application.

[0066] like Figure 14As shown, the planning device provided in this embodiment is applied to an electronic device for planning the overall impeller measurement path based on local analytical constraints. This electronic device can be understood as a computer, server, or cloud platform with data computing and information processing capabilities. Specifically, the planning device includes a measurement point distribution module 10, a coarse screening and region division module 20, an open area fine screening module 30, a restricted area pre-screening module 40, a restricted area verification module 50, and a path planning module 60.

[0067] The measurement point distribution module is used to construct isoparametric curves for the surface under test and to adaptively distribute measurement points based on NURBS curves and curvature changes.

[0068] First, the isoparametric discrete curve method is used to extract characteristic curves from the complex surfaces of the known CAD model, and the spatial geometry of the surface is fully represented by the characteristic curves. NURBS curves are then used to represent the isoparametric curves, and an adaptive distribution of curvature measurement points is implemented based on these curves.

[0069] The coarse screening and region partitioning module is used to perform discrete generation of attitude rays, coarse screening, and adaptive region partitioning.

[0070] After completing the distribution planning of measurement points on the surface to be measured, the Fibonacci spherical lattice method is introduced to discretize the probe's measurement posture in three-dimensional space, using the center of the sphere at each measurement point as the origin. This method generates a spherical spiral point set based on the golden section angle, and ensures that the discrete sampling vectors are uniformly distributed isotropically on the unit sphere by linearly dividing the longitudinal height coordinate and strictly controlling the circumferential azimuth angle using irrational angle increments. In this embodiment, the initial number of discrete directions in the single-point posture space is set to 2000.

[0071] Subsequently, the above spatial discrete rays are initially screened using three criteria: local surface normal constraint of the measuring point, limit constraint of the machine tool rotation axis angle, and anti-collision constraint of the machine tool worktable. Invalid directions that do not meet the above criteria are eliminated to obtain a coarse screening attitude ray set.

[0072] The open area fine screening module is used to perform global ray-model bounded intersection detection in open areas.

[0073] For measurement points in unobstructed open areas, since the space is open and the probability of being blocked by adjacent blades is extremely low, the coarse screening attitude ray set obtained above can be directly subjected to global ray-model bounded intersection detection with the overall impeller model without the need for additional local pre-screening steps.

[0074] In practice, attitude rays are constructed using `gp_Dir` and `gp_Lin`, and the bounded intersection of the rays with the global model `TopoDS_Shape` is performed using OCCT's `BRepIntCurveSurface_Inter`. Collision detection is then performed on each attitude ray in the coarse-screened set, eliminating interfering attitudes and retaining collision-free rays, thus obtaining the open-area interference-free fine-screened attitude set. Since the attitude space of the measurement points in the open area is relatively ample, a large proportion of the coarse-screened rays can already be interfered globally, and the computational load in this region does not constitute a bottleneck.

[0075] The restricted area pre-screening module is used to perform pre-screening of local spatial constraint circles and geometric analysis in restricted areas.

[0076] For measurement points within the confined flow channel region, the probe attitude space is severely compressed by the high-pressure and low-pressure surfaces of adjacent blades. If a global intersection is directly performed on all coarse-screening attitude rays, many geometrically infeasible rays would still require individual collision detection with the overall impeller model, resulting in significant computational waste. Therefore, this implementation introduces a local spatial constraint circle for geometric analytical pre-screening before global intersection. The specific pre-screening process has been detailed above and will not be repeated here.

[0077] Through geometric analysis pre-screening, a large number of candidate poses that are obviously not geometrically feasible in the confined area of ​​the flow channel are eliminated before entering the global intersection calculation, which significantly reduces the number of rays that need to be detected for physical collisions in the later stage, thereby effectively alleviating the computing power bottleneck in the narrow flow channel region.

[0078] The restricted area verification module is used to perform global intersection verification of restricted areas and secondary screening of backtracking points.

[0079] After the above geometric pre-screening, the number of rays in the confined area pre-screened attitude ray set has been significantly reduced. To ensure the absolute safety of the final detection attitude, a global ray-model bounded intersection test is performed between this confined area pre-screened attitude ray set and the overall impeller model. Then, BRepIntCurveSurface_Inter is called again to perform bounded intersection tests between each pre-screened ray and the overall model TopoDS_Shape, eliminating interfering attitudes and obtaining a collision-free reachable attitude set in the confined area, such as... Figure 8 As shown.

[0080] The path planning module is used to perform continuous measurable segment construction and global path optimization.

[0081] Based on the above operations that yielded the open-area interference-free fine-screen attitude set and the confined-area collision-free reachable attitude set, the reachable probe attitudes for each measuring point are first determined. For each measuring point, the optimal attitude is selected from its corresponding attitude set as its reachable probe attitude, thus establishing a global mapping relationship between measuring points and their reachable attitudes. The specific execution process has been detailed above and will not be repeated here.

[0082] After obtaining the final measurement point coordinates, probe posture data, and motion paths between measurement points, these data are input into the post-processing equipment. The post-processing equipment transforms the optimized measurement point coordinates and probe optimal posture into the machine tool workpiece coordinate system using matrix transformation, generates a G-code program for actual machine tool measurement, outputs the measurement point execution sequence and probe posture data, and completes the overall impeller in-machine measurement path planning.

[0083] As can be seen from the above technical solution, this application provides an overall impeller measurement path planning device. This device is applied to electronic equipment, specifically for the adaptive distribution of measurement points on the surface to be measured; coarse screening of attitude rays using local surface normal constraints of measurement points, machine tool rotation axis angle limit constraints, and machine tool worktable anti-collision constraints, to obtain a coarse-screened attitude ray set; selecting projection lines and projecting them onto the surface to be measured along the surface normal, and adaptively dividing the global measurement points of the impeller into an unobstructed open area and a flow channel restricted area based on the projection boundary lines; obtaining a non-interference fine screening attitude set for measurement points in the unobstructed open area; obtaining a pre-screened attitude ray set for measurement points in the flow channel restricted area; performing global ray-model bounded intersection detection between the pre-screened attitude ray set in the restricted area and the overall impeller model to obtain a collision-free reachable attitude set in the restricted area; and performing global path optimization based on the non-interference fine screening attitude set in the open area and the collision-free reachable attitude set in the restricted area to obtain the measurement point execution sequence and probe attitude data. Specific implementation shows that this solution can significantly shorten the calculation time of reachable cones, thereby avoiding wasted computing power.

[0084] The units described in the embodiments of this disclosure can be implemented in software or in hardware. The name of a unit does not necessarily limit the unit itself; for example, the first acquisition unit can also be described as "a unit that acquires at least two Internet Protocol addresses".

[0085] The functions described above in this document can be performed at least in part by one or more hardware logic components. For example, exemplary types of hardware logic components that can be used, without limitation, include: field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), system-on-a-chip (SoCs), complex programmable logic devices (CPLDs), and so on.

[0086] Figure 15This is a block diagram of an electronic device according to an embodiment of this application.

[0087] The following is for reference. Figure 15 This document illustrates a structural diagram suitable for implementing the electronic device in the embodiments of this disclosure. The terminal device in the embodiments of this disclosure may include, but is not limited to, mobile terminals such as mobile phones, laptops, digital broadcast receivers, PDAs (personal digital assistants), PADs (tablet computers), PMPs (portable multimedia players), in-vehicle terminals (e.g., in-vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. This electronic device is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this disclosure.

[0088] The electronic device may include a processing unit (e.g., a central processing unit, a graphics processing unit, etc.) 601, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 602 or a program loaded from an input device 606 into a random access memory (RAM) 603. The RAM also stores various programs and data required for the operation of the electronic device. The processing unit, ROM, and RAM are interconnected via a bus 604. An input / output (I / O) interface 605 is also connected to the bus 604.

[0089] Typically, the following devices can be connected to the I / O interface: input devices including, for example, touchscreens, touchpads, keyboards, mice, cameras, microphones, accelerometers, gyroscopes, etc.; output devices 607 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 608 including, for example, magnetic tapes, hard disks, etc.; and communication devices 609. Communication device 609 allows the electronic device to communicate wirelessly or wiredly with other devices to exchange data. Although electronic devices with various devices are shown in the figures, it should be understood that it is not required to implement or possess all of the devices shown. More or fewer devices may be implemented or possessed alternatively.

[0090] This application also provides an embodiment of a computer-readable storage medium.

[0091] The aforementioned computer-readable storage medium is applied to an electronic device and carries one or more computer programs. When the electronic device executes these programs, it causes the device to adaptively distribute measurement points on the surface under test. The attitude rays are coarsely screened using local surface normal constraints, machine tool rotation axis angle limit constraints, and machine tool table anti-collision constraints to obtain a coarsely screened attitude ray set. Projection lines are selected and projected onto the surface under test along the surface normal. Based on the projection boundary lines, the global measurement points of the impeller are adaptively divided into an unobstructed open area and a flow channel restricted area. For measurement points in the unobstructed open area, a non-interference fine-screening attitude set for the open area is obtained. For measurement points in the flow channel restricted area, a pre-screening attitude ray set for the restricted area is obtained. The pre-screening attitude ray set for the restricted area is used to perform a global ray-model bounded intersection detection with the overall impeller model to obtain a collision-free reachable attitude set for the restricted area. Based on the non-interference fine-screening attitude set for the open area and the collision-free reachable attitude set for the restricted area, global path optimization is performed to obtain the measurement point execution sequence and probe attitude data. Specific implementation shows that this scheme can significantly shorten the computation time for reachable cones, thereby avoiding the waste of computing power.

[0092] It should be noted that the computer-readable medium described above in this disclosure can be a computer-readable signal medium or a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof.

[0093] In this disclosure, a computer-readable storage medium can be any tangible medium that contains or stores a program that can be used by or in connection with an instruction execution system, apparatus, or device. In this disclosure, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wires, optical fibers, RF (radio frequency), etc., or any suitable combination thereof.

[0094] It should also be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. In addition, in the device embodiment drawings provided in this application, the connection relationship between modules indicates that they have a communication connection, which can be implemented as one or more communication buses or signal lines.

[0095] Through the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware, or it can be implemented by special-purpose hardware including application-specific integrated circuits, special-purpose CPUs, special-purpose memory, special-purpose components, etc. Generally, any function performed by a computer program can be easily implemented by corresponding hardware, and the specific hardware structure used to implement the same function can also be diverse, such as analog circuits, digital circuits, or special-purpose circuits. However, for this application, software program implementation is more often the preferred implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a readable storage medium, such as a computer floppy disk, USB flash drive, mobile hard disk, ROM, RAM, magnetic disk, or optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, training equipment, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0096] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product.

[0097] The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions may be transmitted from one website, computer, training device, or data center to another website, computer, training device, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can store or a data storage device such as a training device or data center that integrates one or more available media. The available media may be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state drives (SSDs)).

Claims

1. A method for integral impeller measurement path planning, applied to an electronic device, comprising: The overall impeller measurement path planning method includes the following steps: Isoparametric curves are constructed for the surface under test, and the distribution of measurement points is adaptively determined based on the NURBS curves and curvature changes. Using the center of the measuring ball at each measuring point as the origin, attitude rays are discretized in space. The attitude rays are coarsely screened using the local surface normal constraint of the measuring point, the machine tool rotation axis angle limit constraint, and the machine tool worktable anti-collision constraint to obtain a coarsely screened attitude ray set. The projection line is selected and projected onto the surface to be measured along the surface normal. Based on the projection boundary line, the global measuring points of the impeller are adaptively divided into an unobstructed open area and a flow channel restricted area. For the measurement points in the unobstructed open area, the coarse screening attitude ray set and the overall impeller model are subjected to global ray-model bounded intersection detection to obtain the open area non-interference fine screening attitude set. For the measuring points in the confined area of ​​the flow channel, a local spatial constraint circle is constructed based on the positional relationship of the outer contour lines of adjacent blades in the local space of the flow channel. The local spatial constraint circle is used to perform geometric analysis pre-screening on the coarse screening attitude ray set, and the rays that interfere with the local spatial constraint circle are removed to obtain the confined area pre-screening attitude ray set. The restricted area pre-screened attitude ray set is subjected to global ray-model bounded intersection detection with the overall impeller model to obtain the restricted area collision-free reachable attitude set. Based on the set of non-interference fine screening attitudes in the open area and the set of non-collision reachable attitudes in the restricted area, the reachable probe attitudes of each measuring point are determined; Using the minimum rotation angle for attitude transfer between adjacent measuring points as a constraint, measuring points with reachable probe attitudes are constructed as continuous measurable segments. Global path optimization is performed on each continuous measurable segment to obtain the measuring point execution sequence and probe attitude data.

2. The integrated impeller measurement path planning method of claim 1, wherein, The process of constructing isoparametric curves for the surface under test and adaptively distributing measurement points based on NURBS curves and curvature changes includes the following steps: Extract the NURBS geometric model information of the impeller surface to be measured, and construct isoparametric curves within the parameter domain; The curvature change rate at each node on the surface is calculated. The sampling density of the measuring points is increased in the high curvature region where the curvature change is drastic, and the sampling density of the measuring points is decreased in the region where the curvature change is gentle, so as to achieve an adaptive discrete distribution of the measuring points on the isoparametric curve.

3. The overall impeller measurement path planning method as described in claim 1, characterized in that, The process involves using the center of the measuring sphere at each measuring point as the origin, discretizing attitude rays in space, and using local surface normal constraints, machine tool rotation axis angle limit constraints, and machine tool table anti-collision constraints to coarsely screen the attitude rays, obtaining a coarsely screened attitude ray set; selecting projection lines and projecting them along the surface normal onto the surface to be measured, and adaptively dividing the global measuring points of the impeller into an unobstructed open area and a flow channel restricted area based on the projection boundary lines, including the following steps: Using the Fibonacci spherical lattice method, spherical direction rays are generated in space, starting from the center of each sphere; Using the local surface normal constraint of the measuring point, the machine tool rotation axis angle limit constraint, and the machine tool worktable anti-collision constraint as three criteria, the spherical direction rays are initially screened, and invalid directions that do not meet the above criteria are eliminated to obtain the coarse screening attitude ray set; Select a projection line and project it onto the surface to be measured along the normal of the surface. Extract the projection point set to construct the projection boundary line. By calculating the sign distance and positional relationship between the measurement point and the projection boundary line, the global measurement points are adaptively divided into unobstructed open areas and flow channel restricted areas.

4. The integral impeller measurement path planning method as described in claim 1, characterized in that, The global ray-model bounded intersection detection calls the ray-surface bounded intersection interface of the geometric kernel to perform collision detection on each attitude ray in the coarse screening attitude ray set and the overall impeller 3D solid model, and retains the attitude rays without collision as the open area non-interference fine screening attitude set.

5. The overall impeller measurement path planning method as described in claim 1, characterized in that, The method involves constructing a local spatial constraint circle for the measuring points within the confined flow channel based on the positional relationship of the outer contour lines of adjacent blades in the local space of the flow channel. This local spatial constraint circle is then used to perform geometric analytical pre-screening of the coarse-screening attitude ray set, eliminating rays that interfere with the local spatial constraint circle, thus obtaining the pre-screened attitude ray set for the confined area. The steps include: For any measuring point located in the confined flow channel area, calculate the tangent vector of the measuring point on its isoparametric curve. Draw a spatial perpendicular line to the tangent vector through the measuring point, so that it intersects the outer contour line of the adjacent low-pressure surface at point A. Search for the point B closest to point A on the outer contour line of the adjacent high-pressure surface. Construct the local spatial constraint circle with line segment AB as the diameter and the midpoint O of line segment AB as the center. Set the angle between the normal vector of the circle plane and the vector from the measuring point to point A to be the smallest, so as to ensure that the constraint surface faces outward. Calculate the intersection parameters of the candidate attitude rays in the coarse screening attitude ray set with the local spatial constraint circle, determine that the ray crosses in the positive direction and the intersection point falls within the radius of the local spatial constraint circle, and retain the rays that satisfy the above determination as the restricted area pre-screening attitude ray set.

6. The integral impeller measurement path planning method as described in claim 1, characterized in that, The step of performing global ray-model bounded intersection detection between the pre-screened attitude ray set of the restricted area and the overall impeller model includes the following steps: After obtaining the set of collision-free reachable postures in the restricted area, the non-interference rays in the set of collision-free reachable postures in the restricted area are reconstructed with the center of the measuring ball at the corresponding retreat point as the starting point, and a second intersection fine screening is performed. The posture after passing the second intersection fine screening is taken as the final non-interference reachable probe posture of the measuring point in the restricted area of ​​the flow channel.

7. The integral impeller measurement path planning method as described in claim 1, characterized in that, The global path optimization employs an adaptive genetic algorithm based on the Tent-Logistic-Cosine chaotic mapping. With the goal of minimizing the non-measurement travel distance between measurement points, the algorithm iteratively optimizes the execution sequence of measurement points within each continuous measurable segment to obtain the globally optimal measurement path.

8. An integral impeller measurement path planning device, applied to electronic equipment, characterized in that, The overall impeller measurement path planning device includes: The measurement point distribution module is configured to construct isoparametric curves for the surface under test and adaptively distribute measurement points based on NURBS curves and curvature changes. The coarse screening and region division module is configured to generate attitude rays in space with the center of the measuring ball at each measuring point as the origin. The attitude rays are coarsely screened using the local surface normal constraint of the measuring point, the machine tool rotation axis angle limit constraint, and the machine tool worktable anti-collision constraint to obtain a coarse screening attitude ray set. The projection line is selected and projected onto the surface to be measured along the surface normal. Based on the projection boundary line, the global measuring points of the impeller are adaptively divided into an unobstructed open area and a flow channel restricted area. The open area fine screening module is configured to perform global ray-model bounded intersection detection on the coarse screening attitude ray set and the overall impeller model for the measurement points in the unobstructed open area, so as to obtain the open area non-interference fine screening attitude set. The restricted area pre-screening module is configured to construct a local spatial constraint circle for the measuring points within the restricted area of ​​the flow channel based on the positional relationship of the outer contour lines of adjacent blades in the local space of the flow channel. The local spatial constraint circle is used to perform geometric analytical pre-screening on the coarse screening attitude ray set, and the rays that interfere with the local spatial constraint circle are removed to obtain the restricted area pre-screening attitude ray set. The restricted area verification module is configured to perform global ray-model bounded intersection detection on the pre-screened attitude ray set of the restricted area and the overall impeller model to obtain a set of collision-free reachable attitudes in the restricted area. The path planning module is configured to determine the reachable probe posture of each measuring point based on the non-interference fine screening posture set in the open area and the non-collision reachable posture set in the restricted area; using the minimum rotation angle of posture transfer between adjacent measuring points as a constraint, measuring points with reachable probe postures are constructed into continuous measurable segments, and global path optimization is performed on each continuous measurable segment to obtain the measuring point execution sequence and probe posture data.

9. An electronic device, characterized in that, The electronic device includes at least one processor and a memory connected to the processor, wherein: The memory is used to store computer programs or instructions; The processor is used to execute the computer program or instructions to enable the electronic device to implement the overall impeller measurement path planning method as described in any one of claims 1 to 7.

10. A computer-readable storage medium for use in electronic devices, characterized in that, The storage medium carries one or more computer programs that can be executed by the electronic device, thereby enabling the electronic device to implement the overall impeller measurement path planning method as described in any one of claims 1 to 7.

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