1. The method for improving the local pose accuracy of the component by optimizing and constructing the measuring points is characterized in that n measuring points are arranged on the component, wherein n is more than or equal to 5, the n measuring points comprise m delta tolerance measuring points and p eta tolerance measuring points, n is m + p, n is more than or equal to 4, eta is more than delta, the measuring points are called initial points before the component is subjected to pose adjustment positioning and are called target points after the pose adjustment positioning, and the measuring point optimizing and constructing method for improving the local pose positioning accuracy of the component comprises the following steps:

step 1, measuring and acquiring a coordinate set A of initial points of m delta tolerances relative to a reference coordinate system { R }¹：

Step 2, acquiring a coordinate set B of p initial points with eta tolerance relative to a reference coordinate system { R }¹：

Step 3, a local coordinate system { D } fixedly connected on the component is constructed, and the coordinate of the initial point relative to the local coordinate system { D } is obtained, and the method comprises the following steps:

3-1 setting the centroid of the initial point of the m delta tolerances as the origin of the local coordinate system { D };

3-2, taking the original point as a starting point, respectively taking the initial points of m delta tolerances as end points to obtain m vectors, and taking the vector with the maximum modulus in the vector as the x direction of the local coordinate system { D };

3-3, respectively cross-multiplying the rest m-1 vectors with the x-direction vector to obtain new m-1 vectors, and taking the vector with the largest modulus in the new m-1 vectors as the z direction of the local coordinate system { D };

3-4, turning the four fingers of the right hand from the z direction to the x direction, wherein the pointing direction of the thumb is the y direction of the local coordinate system { D };

3-5 obtaining a set a of coordinates of an initial point of the n measurement points with respect to the local coordinate system { D }¹：

Step 4, before adjusting the posture and positioning, constructing a matrix equation F (x y z alpha beta gamma), and solving six unknown quantities [ x y z alpha beta gamma ]:

the following were obtained:

wherein c represents a cosine function cos, s represents a sine function sin, x, y, z represent line coordinate components of the origin of the local coordinate system { D } relative to the reference coordinate system { R }, and α, β, γ represent angular coordinate components of the three directions of the local coordinate system { D } relative to the reference coordinate system { R };

step 5, obtaining the coordinates of the m delta tolerance target points relative to the reference coordinate system { R } and the tolerance set A thereof²：

Step 6, obtaining the coordinates of p eta tolerance target points relative to a reference coordinate system { R } and a tolerance set B thereof²：

Step 7 of constructing effective criteria for p η tolerance measurement points, wherein d_ijActual length of initial point of two η tolerances, D_ijTheoretical length of target point for two η tolerances:

finding out all jth eta tolerance measurement points which do not meet the requirement of the criterion of the formula 10, and removing the jth eta tolerance measurement points, wherein i is more than or equal to 1 and less than or equal to m and j is less than or equal to n;

step 8, screening the eta tolerance measuring points meeting the step 7 to form effective eta tolerance measuring points, forming the effective measuring points by the m delta tolerance measuring points and the effective eta tolerance measuring points, and obtaining a coordinate set c of the initial point of the effective measuring points relative to a local coordinate system { D }¹：

Obtaining a coordinate set C of a target point corresponding to the effective measuring point relative to a reference coordinate system { R }²：

Step 9, constructing a function min (x y z α β γ) containing six unknowns, and solving the function to obtain a solution of the unknowns when the minimum value is obtained:

wherein c represents a cosine function cos, s represents a sine function sin, x, y and z represent line coordinate components of the origin of the centrolizing coordinates formed by the effective measuring points relative to the reference coordinate system { R }, and alpha, beta and gamma represent angle coordinate components of three directions of the centrolizing coordinates formed by the effective measuring points relative to the reference coordinate system { R };

solving to obtain:

step 10, constructing a transformation matrix T before and after the effective measurement point attitude adjustment positioning of the components:

wherein c represents a cosine function cos, s represents a sine function sin;

step 11, transforming the initial point of the effective measurement point into the construction point of the effective measurement point by transforming the matrix T, and obtaining a coordinate set C of the construction point of the effective measurement point relative to a reference coordinate system { R }^T：

Step 12, calculating the position deviation value of the construction point and the target point of the effective eta tolerance measurement point:

wherein, Delta_kx、Δ_ky、Δ_kzPositional deviation of construction points and target points, respectively representing effective η tolerance measurement pointsThree coordinate components from the reference coordinate system { R };

step 13 constructs the preferred criterion of the effective eta tolerance measuring point:

step 14, selecting the effective eta tolerance measurement points satisfying the formula 18 to form preferred effective eta tolerance measurement points, forming preferred effective measurement points by using the m delta tolerance measurement points and the preferred effective eta tolerance measurement points, and acquiring a coordinate set D of an initial point of the preferred effective measurement points relative to a local coordinate system { D }¹：

Obtaining a set D of coordinates of a target point of a preferred valid measurement point with respect to a reference coordinate system { R }²：

Step 15, when the number of the optimized effective eta tolerance measuring points is one half or more of the number of the effective eta tolerance measuring points, obtaining a coordinate set D of the construction points of the optimized effective measuring points relative to a reference coordinate system { R }^T：

Step 16, when the number of preferred effective η tolerance measurement points is less than one-half of the number of effective η tolerance measurement points, constructing a function min (Α Β Γ) containing three unknowns, and solving the solution of the unknowns when the function takes a minimum value:

wherein c denotes a cosine function cos, s denotes a sine function sin, and A, BETA, Γ denote angular coordinate components of three directions of centroidal coordinates constituted by preferred effective measurement points with respect to a reference coordinate system { R };

solving to obtain:

step 17, constructing a correction transformation matrix T before and after the component posture adjustment positioning^C：

Wherein c represents a cosine function cos, s represents a sine function sin;

step 18 by modifying the transformation matrix T^CThe initial point correction of the preferred effective measuring point is transformed into the construction point of the preferred effective measuring point, and the coordinate set of the construction point of the preferred effective measuring point relative to the reference coordinate system { R } is obtained

2. The method for improving the local pose accuracy of the zero components by optimizing and constructing the measurement points according to claim 1, wherein the poses of the zero components before the pose alignment positioning are random and the poses after the pose alignment positioning are determined.

3. The method for improving the local pose accuracy of the component parts by optimizing and constructing the measurement points according to claim 1, wherein the length between the initial points of any two δ tolerances does not exceed the length range covered by the target points corresponding to the two points and the tolerances thereof.

4. The method for improving the local pose accuracy of the component parts by optimizing and constructing the measurement points according to claim 1, wherein the optimized effective measurement points are required to envelop one half and more than one half of the whole component parts.

Background

The posture adjustment of the components refers to the rotation of the components around three axes of a coordinate system XYZ; the positioning of the component refers to the movement of the component around three axes of the coordinate system XYZ. The position and the posture of the airplane component can be uniquely determined through attitude adjusting and positioning, and high-precision assembly of the airplane component is realized.

The airplane is assembled by a large number of components through posture adjustment and positioning. When adjusting, positioning and assembling some components, higher local precision is required on the premise of meeting basic overall precision. For example, a flap for lifting the lift of an aircraft is not a fixed component but a movable component including a moving mechanism, and when the aircraft takes off, the flap extends out from the wing to increase the force-bearing area of the wing in order to increase the lift of the aircraft. It follows that the flap not only needs to satisfy the overall accuracy of the aerodynamic profile, but also needs to satisfy the local accuracy of the movement of its telescopic mechanism, which in general is much higher than the overall accuracy, and needs to satisfy the local accuracy preferentially.

In order to meet the local precision of the airplane component in the attitude adjusting positioning assembly process, at least four measuring points with higher precision are required to be arranged on the local part of the airplane component, at least one measuring point with lower precision is arranged in other areas, the local precision of the component is evaluated by using the coordinates of the local measuring points, and the overall precision of the component is evaluated by using the coordinates containing the local measuring points and the non-local measuring points. In order to realize the local precision of the attitude adjustment positioning of the airplane components, the currently adopted technical scheme is as follows: firstly, local precision is met by correcting the local structure of the zero assembly, although the method is feasible, the efficiency is low, the cost is high, and in most cases, the positions of only part of measuring points can be corrected; and secondly, a local shape-preserving tool is arranged, and local deformation of the component is controlled through the shape-preserving tool with high rigidity.

Disclosure of Invention

In order to ensure that the component can ensure higher local precision on the premise of meeting the overall precision in the process of adjusting and positioning the attitude, the invention provides a measuring point optimization and construction method for improving the local precision of adjusting and positioning the attitude of the component.

The invention adopts the following technical scheme:

the method for improving the local pose accuracy of the component by optimizing and constructing the measuring points is characterized in that the component is provided with n measuring points, n is more than or equal to 5, the n measuring points comprise m delta tolerance measuring points and p eta tolerance measuring points, n is m + p, n is more than m is more than or equal to 4, eta is more than delta, the measuring points are called initial points before the component is adjusted in pose and positioned and are called target points after the component is adjusted in pose and positioned, and the method for optimizing and constructing the measuring points for improving the local pose positioning accuracy of the component comprises the following steps:

step 1, measuring and acquiring a coordinate set A of initial points of m delta tolerances relative to a reference coordinate system { R }¹：

Step 2, acquiring a coordinate set B of p initial points with eta tolerance relative to a reference coordinate system { R }¹：

Step 3, a local coordinate system { D } fixedly connected on the component is constructed, and the coordinate of the initial point relative to the local coordinate system { D } is obtained, and the method comprises the following steps:

3-1 setting the centroid of the initial point of the m delta tolerances as the origin of the local coordinate system { D };

3-2, taking the original point as a starting point, respectively taking the initial points of m delta tolerances as end points to obtain m vectors, and taking the vector with the maximum modulus in the vector as the x direction of the local coordinate system { D };

3-3, respectively cross-multiplying the rest m-1 vectors with the x-direction vector to obtain new m-1 vectors, and taking the vector with the largest modulus in the new m-1 vectors as the z direction of the local coordinate system { D };

3-4, turning the four fingers of the right hand from the z direction to the x direction, wherein the pointing direction of the thumb is the y direction of the local coordinate system { D };

3-5 obtaining a set a of coordinates of an initial point of the n measurement points with respect to the local coordinate system { D }¹：

Step 4, before adjusting the posture and positioning, constructing a matrix equation F (x y z alpha beta gamma), and solving six unknown quantities [ x y z alpha beta gamma ]:

the following were obtained:

wherein c represents a cosine function cos, s represents a sine function sin, x, y, z represent line coordinate components of the origin of the local coordinate system { D } relative to the reference coordinate system { R }, and α, β, γ represent angular coordinate components of the three directions of the local coordinate system { D } relative to the reference coordinate system { R };

step 5, obtaining the coordinates of the m delta tolerance target points relative to the reference coordinate system { R } and the tolerance set A thereof²：

Step 6, obtaining the coordinates of p eta tolerance target points relative to a reference coordinate system { R } and a tolerance set B thereof²：

Step 7 of constructing effective criteria for p η tolerance measurement points, wherein d_ijIs a tolerance of two etaOf the initial point, D_ijTheoretical length of target point for two η tolerances:

finding out all jth eta tolerance measurement points which do not meet the requirement of the criterion of the formula 10, and removing the jth eta tolerance measurement points, wherein i is more than or equal to 1 and less than or equal to m and j is less than or equal to n;

step 8, screening the eta tolerance measuring points meeting the step 7 to form effective eta tolerance measuring points, forming the effective measuring points by the m delta tolerance measuring points and the effective eta tolerance measuring points, and obtaining a coordinate set c of the initial point of the effective measuring points relative to a local coordinate system { D }¹：

Obtaining a coordinate set C of a target point corresponding to the effective measuring point relative to a reference coordinate system { R }²：

Step 9, constructing a function min (x y z α β γ) containing six unknowns, and solving the function to obtain a solution of the unknowns when the minimum value is obtained:

wherein c represents cos and s represents sin. Formula 13;

wherein c represents a cosine function cos, s represents a sine function sin, x, y and z represent line coordinate components of the origin of the centrolizing coordinates formed by the effective measuring points relative to the reference coordinate system { R }, and alpha, beta and gamma represent angle coordinate components of three directions of the centrolizing coordinates formed by the effective measuring points relative to the reference coordinate system { R };

solving to obtain:

step 10, constructing a transformation matrix T before and after the effective measurement point attitude adjustment positioning of the components:

wherein c represents a cosine function cos, s represents a sine function sin;

step 11, transforming the initial point of the effective measurement point into the construction point of the effective measurement point by transforming the matrix T, and obtaining a coordinate set C of the construction point of the effective measurement point relative to a reference coordinate system { R }^T：

Step 12, calculating the position deviation value of the construction point and the target point of the effective eta tolerance measurement point:

wherein, Delta_kx、Δ_ky、Δ_kzThree coordinate components of the deviation of the positions of the construction point and the target point respectively representing the effective eta tolerance measurement point from the reference coordinate system { R };

step 13 constructs the preferred criterion of the effective eta tolerance measuring point:

step 14, selecting the effective eta tolerance measurement points satisfying the formula 18 to form preferred effective eta tolerance measurement points, and combining the m delta tolerance measurement points and the preferred effective eta tolerance measurement pointsObtaining a coordinate set D of an initial point of the preferred effective measuring point relative to a local coordinate system { D }, wherein the initial point is a preferred effective measuring point¹：

Obtaining a set D of coordinates of a target point of a preferred valid measurement point with respect to a reference coordinate system { R }²：

Step 15, when the number of the optimized effective eta tolerance measuring points is one half or more of the number of the effective eta tolerance measuring points, obtaining a coordinate set D of the construction points of the optimized effective measuring points relative to a reference coordinate system { R }^T：

Step 16, when the number of the preferred effective η tolerance measurement points is less than one-half of the number of the effective η tolerance measurement points, constructing a function min (A B Γ) containing three unknowns, and solving the solution of the unknowns when the function takes a minimum value:

wherein c represents cos and s represents sin.

Formula 22;

wherein c denotes a cosine function cos, s denotes a sine function sin, A, B, Γ denotes the angular coordinate components of the three directions of the centroidal coordinates of the preferred valid measurement points with respect to the reference coordinate system { R };

solving to obtain:

step 17, constructing a correction transformation matrix T before and after the component posture adjustment positioning^C：

Wherein c represents a cosine function cos, s represents a sine function sin;

step 18 by modifying the transformation matrix T^CThe initial point correction of the preferred effective measuring point is transformed into the construction point of the preferred effective measuring point, and the coordinate set of the construction point of the preferred effective measuring point relative to the reference coordinate system { R } is obtained

The method for improving the local pose accuracy of the component by optimizing and constructing the measuring points is characterized in that the pose of the component before pose adjustment and positioning is random, and the pose after pose adjustment and positioning is determined.

The method for improving the local pose accuracy of the component by optimizing and constructing the measuring points is characterized in that the length between any two initial points of delta tolerance does not exceed the length range covered by the target points corresponding to the two points and the tolerance thereof.

The method for improving the local pose accuracy of the components by optimizing and constructing the measuring points is characterized in that the optimized effective measuring points are required to envelop one half or more of the whole components.

Compared with the prior art, the invention has the following advantages and obvious benefits:

(1) the local precision of the posture-adjusting positioning of the components is improved. The measuring points preferentially constructed by the method disclosed by the application have invariance of the position relation before and after the posture adjustment and positioning, so that the precision of the evaluated components has accuracy.

(2) The working efficiency of the zero assembly posture-adjusting positioning is improved, the measuring points are optimized and constructed through the analysis and transformation of the coordinate data of the measuring points on the zero assembly, and compared with the existing zero assembly shape correction and shape preservation, the efficiency of the posture-adjusting positioning is greatly improved.

The present application is described in further detail below with reference to the accompanying drawings of embodiments:

drawings

FIG. 1 is a pose illustration of an aircraft flap and its measurement points before and after pose alignment.

Fig. 2 is a schematic illustration of a local coordinate system constructed on the basis of m delta tolerance measurement points provided on an aircraft flap.

Fig. 3 is an illustration of η tolerance measurement points that do not meet a validity criterion.

Fig. 4 is a schematic illustration of the matching of the construction points of the active measurement points on the aircraft flap to the target points in a reference coordinate system.

Fig. 5 is a diagram illustrating deviations of the construction point from the target point for the ith δ -tolerance measurement point and the jth effective η -tolerance measurement point, respectively, on the aircraft flap.

The numbering in the figures illustrates: 1 flap box section, 2 flap crossing point, 3 wing back beam, 4 back beam crossing point, 5 flap before attitude adjustment positioning, 6 flap after attitude adjustment positioning, 7 eta tolerance initial point, 8 delta tolerance initial point, 9 eta tolerance target point, 10 delta tolerance target point, 11 eta tolerance measuring point which does not accord with validity criterion, 12 eta tolerance structural point and target point matching, 13 delta tolerance structural point and target point matching, 14 ith delta tolerance structural point, 15 ith delta tolerance target point, 16 ith delta tolerance measuring point tolerance box, 17 jth eta tolerance structural point, 18 jth eta tolerance target point, 19 jth eta tolerance measuring point tolerance box

Detailed Description

As shown in fig. 1, the component in this embodiment is an aircraft flap, the aircraft flap is composed of a flap box 1 and a flap intersection point 2, and the aircraft flap is installed on a back beam intersection point 4 of a wing back beam 3 after being adjusted in posture and positioned. In order to realize the light weight of the structure of the airplane flap, the flap box 1 which accounts for most of the airplane flap is usually made of light honeycomb materials, so that the flap box is weak in rigidity and easy to deform under stress; the flap intersection point 2 occupying a small part of the aircraft flap is made of titanium alloy and other high-rigidity materials, and is not easy to deform when stressed, so that the non-deformation and the stability of the aircraft flap in the process of stretching movement are ensured. Therefore, the attitude adjustment positioning process of the airplane flap needs to improve the local precision as much as possible under the condition of meeting the basic overall precision.

The left side of figure 1 is the flap 5 before attitude adjustment positioning, and the right side of figure 1 is the flap 6 after attitude adjustment positioning. 15 eta tolerance initial points 7 and 8 delta tolerance initial points 8 are arranged on the flap 5 before attitude adjusting and positioning; on the flap 6 after the attitude adjustment positioning, 15 η tolerance target points 9 and 8 δ tolerance target points 10 are provided. Wherein the coordinates of the η tolerance initial point 7 and the δ tolerance initial point 8 with respect to the reference coordinate system { R } are obtained by the measuring device; the coordinates and tolerances of the η and δ tolerance target points 9, 10 with respect to the reference coordinate system { R }, are given by the design.

Due to factors such as deformation of the aircraft flap, the internal position relationship of the initial point (including 15 eta tolerance initial points 7 and 8 delta tolerance initial points 8) on the flap 5 before the attitude adjustment positioning is definitely inconsistent with the internal position relationship of the flap 6 after the attitude adjustment positioning, and part of the initial points on the flap 5 before the attitude adjustment positioning cannot be enveloped in the tolerance box (shown in fig. 3) of the corresponding target point of the flap 6 after the attitude adjustment positioning.

Before the attitude adjustment positioning, on the premise of not correcting or keeping the shape of the aircraft flap, by the method disclosed by the invention, all delta tolerance initial points 8 on the aircraft flap are enveloped in the range of a tolerance box 16 (shown in the left side of FIG. 5) of a corresponding delta tolerance target point 10 after the attitude adjustment positioning, so that the aircraft flap meets the local precision of a flap intersection point 2 in the attitude adjustment positioning process, and meanwhile, part of eta tolerance initial points 7 on the aircraft flap are enveloped in the range of a tolerance box 19 (shown in the right side of FIG. 5) of a corresponding eta tolerance target point 9, so that the aircraft flap meets the basic overall precision in the attitude adjustment positioning process.

The method for improving the local pose accuracy of the component by optimizing and constructing the measuring points is characterized in that the component is provided with n measuring points, n is more than or equal to 5, the n measuring points comprise m delta tolerance measuring points and p eta tolerance measuring points, n is m + p, n is more than m is more than or equal to 4, eta is more than delta, the measuring points are called initial points before the component is adjusted in pose and positioned and are called target points after the component is adjusted in pose and positioned, and the method for optimizing and constructing the measuring points for improving the local pose positioning accuracy of the component comprises the following steps:

step 1, measuring and acquiring a coordinate set A of initial points of m delta tolerances relative to a reference coordinate system { R }¹：

Step 2, acquiring a coordinate set B of p initial points with eta tolerance relative to a reference coordinate system { R }¹：

Step 3, a local coordinate system { D } fixedly connected on the component is constructed, and the coordinate of the initial point relative to the local coordinate system { D } is obtained, and the method comprises the following steps:

3-1 setting the centroid of the initial point of the m delta tolerances as the origin of the local coordinate system { D };

3-2, taking the original point as a starting point, respectively taking the initial points of m delta tolerances as end points to obtain m vectors, and taking the vector with the maximum modulus in the vector as the x direction of the local coordinate system { D };

3-3, respectively cross-multiplying the rest m-1 vectors with the x-direction vector to obtain new m-1 vectors, and taking the vector with the largest modulus in the new m-1 vectors as the z direction of the local coordinate system { D };

3-4, turning the four fingers of the right hand from the z direction to the x direction, wherein the pointing direction of the thumb is the y direction of the local coordinate system { D };

3-5 obtaining a set a of coordinates of an initial point of the n measurement points with respect to the local coordinate system { D }¹：

As shown in fig. 2, is a local coordinate system { D } constructed based on m δ tolerance measurement points provided on the aircraft flap;

step 4, before adjusting the posture and positioning, constructing a matrix equation F (x y z alpha beta gamma), and solving six unknown quantities [ x y z alpha beta gamma ]:

the following were obtained:

wherein c represents a cosine function cos, s represents a sine function sin, x, y, z represent line coordinate components of the origin of the local coordinate system { D } relative to the reference coordinate system { R }, and α, β, γ represent angular coordinate components of the three directions of the local coordinate system { D } relative to the reference coordinate system { R };

step 5, obtaining the coordinates of the m delta tolerance target points relative to the reference coordinate system { R } and the tolerance set A thereof²：

Step 6, obtaining the coordinates of p eta tolerance target points relative to a reference coordinate system { R } and a tolerance set B thereof²：

Step 7 of constructing effective criteria for p η tolerance measurement points, wherein d_ijActual length of initial point of two η tolerances, D_ijTheoretical length of target point for two η tolerances:

finding out all jth eta tolerance measurement points which do not meet the requirement of the criterion of the formula 10, and removing the jth eta tolerance measurement points, wherein i is more than or equal to 1 and less than or equal to m and j is less than or equal to n;

as shown in fig. 3, two η -tolerance measurement points 11 are found which do not meet the validity criterion and are distributed at the two sharp corners of the flap box 1, and are removed;

step 8, screening the eta tolerance measuring points meeting the step 7 to form effective eta tolerance measuring points, forming the effective measuring points by the m delta tolerance measuring points and the effective eta tolerance measuring points, and obtaining a coordinate set c of the initial point of the effective measuring points relative to a local coordinate system { D }¹：

Obtaining a coordinate set C of a target point corresponding to the effective measuring point relative to a reference coordinate system { R }²：

Step 9, constructing a function min (x y z α β γ) containing six unknowns, and solving the function to obtain a solution of the unknowns when the minimum value is obtained:

wherein c represents cos and s represents sin. Formula 13;

wherein c represents a cosine function cos, s represents a sine function sin, x, y and z represent line coordinate components of the origin of the centrolizing coordinates formed by the effective measuring points relative to the reference coordinate system { R }, and alpha, beta and gamma represent angle coordinate components of three directions of the centrolizing coordinates formed by the effective measuring points relative to the reference coordinate system { R };

solving to obtain:

step 10, constructing a transformation matrix T before and after the effective measurement point attitude adjustment positioning of the components:

wherein c represents a cosine function cos, s represents a sine function sin;

step 11, transforming the initial point of the effective measurement point into the construction point of the effective measurement point by transforming the matrix T, and obtaining a coordinate set C of the construction point of the effective measurement point relative to a reference coordinate system { R }^T：

As shown in fig. 4, the construction point of the effective measurement point on the flap wing box 1 is matched with the target point under a reference coordinate system { R }, and the matching 12 of the eta tolerance construction point and the target point and the matching 13 of the delta tolerance construction point and the target point are included;

step 12, calculating the position deviation value of the construction point and the target point of the effective eta tolerance measurement point:

wherein, Delta_kx、Δ_ky、Δ_kzThree coordinate components of the deviation of the positions of the construction point and the target point respectively representing the effective eta tolerance measurement point from the reference coordinate system { R };

as shown in fig. 5, the deviation of the construction point and the target point corresponding to the ith δ tolerance measurement point and the jth effective η tolerance measurement point on the aircraft flap is illustrated, wherein the ith δ tolerance construction point 14 and the ith δ tolerance target point 15 are enveloped in the tolerance box 16 of the ith δ tolerance measurement point on the left of fig. 5; fig. 5 shows on the right the jth η tolerance measurement point within the tolerance box 19, enveloping the jth η tolerance build-up point 17 and the jth η tolerance target point 18;

step 13 constructs the preferred criterion of the effective eta tolerance measuring point:

step 14, selecting the effective eta tolerance measurement points satisfying the formula 18 to form preferred effective eta tolerance measurement points, forming preferred effective measurement points by using the m delta tolerance measurement points and the preferred effective eta tolerance measurement points, and acquiring a coordinate set D of an initial point of the preferred effective measurement points relative to a local coordinate system { D }¹：

Obtaining a set D of coordinates of a target point of a preferred valid measurement point with respect to a reference coordinate system { R }²：

Step 15, when the number of the optimized effective eta tolerance measuring points is one half or more of the number of the effective eta tolerance measuring points, obtaining a coordinate set D of the construction points of the optimized effective measuring points relative to a reference coordinate system { R }^T：

Step 16, when the number of the preferred effective η tolerance measurement points is less than one-half of the number of the effective η tolerance measurement points, constructing a function min (A B Γ) containing three unknowns, and solving the solution of the unknowns when the function takes a minimum value:

wherein c represents cos and s represents sin.

Formula 22;

wherein c denotes a cosine function cos, s denotes a sine function sin, A, B, Γ denotes the angular coordinate components of the three directions of the centroidal coordinates of the preferred valid measurement points with respect to the reference coordinate system { R };

solving to obtain:

step 17, constructing a correction transformation matrix T before and after the component posture adjustment positioning^C：

Wherein c represents a cosine function cos, s represents a sine function sin;

step 18 by modifying the transformation matrix T^CThe initial point correction of the preferred effective measuring point is transformed into the construction point of the preferred effective measuring point, and the coordinate set of the construction point of the preferred effective measuring point relative to the reference coordinate system { R } is obtained

The method for improving the local pose accuracy of the component by optimizing and constructing the measuring points is characterized in that the pose of the component before pose adjustment and positioning is random, and the pose after pose adjustment and positioning is determined.

The method for improving the local pose accuracy of the component by optimizing and constructing the measuring points is characterized in that the length between any two initial points of delta tolerance does not exceed the length range covered by the target points corresponding to the two points and the tolerance thereof.

The method for improving the local pose accuracy of the components by optimizing and constructing the measuring points is characterized in that the optimized effective measuring points are required to envelop one half or more of the whole components.

Compared with the prior art, the invention has the following advantages and obvious benefits:

(1) the local precision of the posture-adjusting positioning of the components is improved. The measuring points preferentially constructed by the method disclosed by the application have invariance of the position relation before and after the posture adjustment and positioning, so that the precision of the evaluated components has accuracy.

(2) The working efficiency of the zero assembly posture-adjusting positioning is improved, the measuring points are optimized and constructed through the analysis and transformation of the coordinate data of the measuring points on the zero assembly, and compared with the existing zero assembly shape correction and shape preservation, the efficiency of the posture-adjusting positioning is greatly improved.