CN105627918B

CN105627918B - Quickly draw tooling and method in axis hole benchmark scene for precision visual measurement

Info

Publication number: CN105627918B
Application number: CN201410635996.3A
Authority: CN
Inventors: 郭磊; 刘柯; 宋金城; 高越; 董利军; 孙增玉; 逯海
Original assignee: China Academy of Launch Vehicle Technology CALT; Beijing Aerospace Institute for Metrology and Measurement Technology
Current assignee: China Academy of Launch Vehicle Technology CALT; Beijing Aerospace Institute for Metrology and Measurement Technology
Priority date: 2014-11-05
Filing date: 2014-11-05
Publication date: 2019-01-08
Anticipated expiration: 2034-11-05
Also published as: CN105627918A

Abstract

The invention belongs to the technical field of precise measurement of geometric quantities, and in particular relates to an on-site rapid extraction tool and method for shaft hole reference used for visual precision measurement, and aims to provide a extraction tool and method. The tooling includes a shaft datum lead-out tool and a hole datum lead-out tool. The method includes five steps of establishing a tooling coordinate system, marking the three-dimensional coordinate value of the center of the directional reflection ball in the tooling coordinate system, installing the shaft hole datum to quickly draw the tooling on site, measuring and data processing. The lead-out tooling of the present invention and the method based on the tooling can effectively solve the problem of measuring the coordinate system and the workpiece coordinates when the visual precision measurement system is used to measure the large-scale mechanical parts whose workpiece coordinate system is defined by the intersection of the axis of the shaft or the hole and the reference plane as the reference point. The field of the department quickly establishes the problem.

Description

Quickly draw tooling and method in axis hole benchmark scene for precision visual measurement

Technical field

The invention belongs to geometric sense Technology of Precision Measurement fields, and in particular to a kind of axis hole base for precision visual measurement Quickly draw tooling and method in quasi- scene.

Background technique

In geometric sense accurate measurement, it usually needs measured to measured workpiece coordinate system, analyze the geometry of measured workpiece Form and position error, or obtain workpiece coordinate system and measure the spatial relationship of coordinate system, and then complete measurement task.Due to axis hole form Largely it is present in component of machine, using the intersection point of the axis and datum plane in axis or hole as datum mark definition of object co-ordinate systems It is a kind of common Method for Coordinate Definition.In face of above-mentioned measurement problem, in contact type measurement, such as three-dimensional coordinates measurement is utilized Machine measures measured workpiece, can directly carry out sampling site measurement on axis or hole wall using coordinate machine gauge head, pass through cylinder The data processing methods such as fitting obtain the axis of axis hole and the intersection point of datum plane, and then measure workpiece coordinate system.

In precision visual measurement, need to be arranged in measurement space visual properties, measurement exists the result is that feature is arranged The three-dimensional coordinate in space solves the problems, such as the measurement of the above-mentioned measured workpiece that local Coordinate System is defined with axis hole using visible sensation method When, need to establish the relationship between axis hole material standard and vision measurement visual properties, i.e. axis hole base in precision visual measurement Quasi- extraction problem.

Summary of the invention

It is an object of the invention to provide a kind of axis hole benchmark scenes for precision visual measurement quickly to draw tooling and method.

The present invention is implemented as follows:

A kind of axis hole benchmark scene quickly extraction tooling, including axis benchmark extraction tooling and hole for precision visual measurement Benchmark draws tooling.

It includes axis benchmark lead, the first leading-off rods and the first orienting reflex that axis benchmark as described above, which draws tooling, Ball；Wherein, axis benchmark lead is that made of metal is circular, is matching hole, internal diameter and axis ruler inside axis benchmark lead Very little to match, front end face is benchmark plane；First leading-off rods is " √ " shape that short side is horizontally arranged, one end of the first leading-off rods It is connect with one end of axis benchmark lead, the other end installs the first orienting reflex ball.

It includes hole benchmark lead, the second leading-off rods and the second orienting reflex that hole benchmark as described above, which draws tooling, Ball, hole benchmark lead are ladder-like rotary table, and point diameter is less than rear end diameter, and front end portion, which is used as, matches dowel pin, and second draws One end of rod is connect with the rear end face of hole benchmark lead, and the other end of the second leading-off rods installs the second orienting reflex Ball.

A kind of extraction side for quickly drawing tooling based on the axis hole benchmark scene as described above measured for precision visual Method includes the following steps:

Step 1: establishing tooling coordinate system；

Step 2: D coordinates value of the mark orienting reflex ball centre of sphere under tooling coordinate system；

Step 3: tooling is quickly drawn at mounting shaft hole benchmark scene；

Step 4: measurement；

Step 5: data processing.

Tooling coordinate system step is established as described above, the axis benchmark lead front end surface of tooling is drawn with axis benchmark The leading portion annular shape table top for drawing tooling hole benchmark lead with hole benchmark is respectively the XOY plane of two pieces tooling coordinate system, The hole of axis benchmark lead or hole benchmark draw the friendship of the axis and datum plane with dowel pin of tooling hole benchmark lead Putting is coordinate origin O, and the line of subpoint of the centre of sphere of orienting reflex ball on datum plane and origin O are coordinate system X-axis, Subpoint is directed toward by origin in direction, and what the hole of axis benchmark lead or hole benchmark drew tooling hole benchmark lead matches dowel pin Axis be coordinate system Z axis, direction by origin be directed toward orienting reflex ball direction.

Tooling coordinate system step is established as described above, Accurate Calibration goes out to orient anti-on metering type high accuracy three coordinate machine Penetrate D coordinates value of the ball centre of sphere under respective tooling coordinate system.

Tooling step is quickly drawn at mounting shaft hole benchmark as described above scene, and benchmark extraction tooling is installed to tested machine On the reference axis or datum hole of tool component.

Measuring process as described above is sat using the space that precision visual measuring system measures the fixed direction reflective ball centre of sphere Mark；Make to draw tooling rotating around the hole of axis benchmark lead or hole benchmark draw tooling hole benchmark lead with dowel pin Axis rotation measures directional lighting ball, then rotary tooling using precision visual measuring system, then measures, until tooling rotation one Week.

Data processing step as described above, using the 3 d space coordinate of fixed direction reflective ball and its under tooling coordinate system Coordinate value carry out data processing, solve three-dimensional coordinate of the tooling coordinate origin O in the case where measuring coordinate system.

Data processing step as described above, specifically comprises the following steps:

(1) plane normal vector (A, B, C) is obtained；

If it is (X that benchmark, which draws space coordinate of the fixed direction reflective ball in the case where measuring coordinate system in the entire rotary course of tooling,_m1, Y_m1,Z_m1)、(X_m2,Y_m2,Z_m2)、…、(X_mn,Y_mn,Z_mn) (n >=4), coordinate value of the fixed direction reflective ball under tooling coordinate system be (X_a,0,Z_a)；

By fixed direction reflective ball centre of sphere point coordinate measurement process it is found that all the points in the same plane, if its plane equation is AX+BY+CZ+D=0；By (X_mi,Y_mi,Z_mi) (i=1,2 ..., n, n >=4) bring into equation constitute Simultaneous Equations, solve flat Face equation parameter (A, B, C, D) obtains plane normal vector (A, B, C)；

(2) central coordinate of circle (X is calculated_c, Y_c, Z_c)；

By fixed direction reflective ball centre of sphere point coordinate measurement process it is found that all the points are on the same circle, if its equation is (X- X_c)²+(Y-Y_c)²+(Z-Z_c)²=R², unknown parameter (X can be solved by bringing all the points coordinate into equation_c, Y_c, Z_c) and R；

(3) coordinate value (X of the work coordinate system origin O in the case where measuring coordinate system is calculated_o, Y_o, Z_o)；

Utilize vector (A, B, C) and coordinate (X_c, Y_c, Z_c) obtain one, space mistake (X_o, Y_o, Z_o) and direction vector be (A, B, C) linear equation, which is the Z axis of tooling coordinate system, linearly uncompensation distance Z_a, acquire work coordinate system original Coordinate value (X of the point O in the case where measuring coordinate system_o, Y_o, Z_o)。

The beneficial effects of the present invention are:

Extraction tooling of the invention and the method based on the tooling can effectively solve the problem that be surveyed using precision visual measuring system When measuring the large scale machine parts using the intersection point of the axis and datum plane in axis or hole as datum mark definition of object co-ordinate systems, measurement Problem is quickly established at the scene of coordinate system and workpiece coordinate system.

Detailed description of the invention

Fig. 1 is that the axis benchmark that tooling is quickly drawn at a kind of axis hole benchmark scene for precision visual measurement of the invention draws The structural schematic diagram of tooling out；

Fig. 2 is that the hole benchmark that tooling is quickly drawn at a kind of axis hole benchmark scene for precision visual measurement of the invention draws The structural schematic diagram of tooling out；

Fig. 3 is using a kind of Kong Ji for quickly drawing tooling for the axis hole benchmark scene of precision visual measurement of the invention Standard draws the flow chart of the method for tooling；

In figure: 1. axis benchmark leads, 2. first leading-off rods, 3. first orienting reflex balls, 4. hole benchmark leads, 5. the second leading-off rods, 6. second orienting reflex balls.

Specific embodiment

With reference to the accompanying drawings and examples quickly to a kind of axis hole benchmark scene for precision visual measurement of the invention It draws tooling and method is introduced:

A kind of axis hole benchmark scene quickly extraction tooling, including axis benchmark extraction tooling and hole for precision visual measurement Benchmark draws tooling, wherein as shown in Figure 1, it includes axis benchmark lead 1, the first leading-off rods 2 and that axis benchmark, which draws tooling, One orientation reflection sphere 3.Wherein, axis benchmark lead 1 is that made of metal is circular, its inside is matching hole, internal diameter and axis Size matches, its front end face is benchmark plane.First leading-off rods 2 is " √ " shape that short side is horizontally arranged, and first draws One end of bar is connect with one end of axis benchmark lead, and the other end installs the first orienting reflex ball 3.As shown in Fig. 2, hole benchmark Drawing tooling includes hole benchmark lead 4, the second leading-off rods 5 and the second orienting reflex ball 6, and hole benchmark lead 4 is rank Scalariform rotary table, point diameter are less than rear end diameter, and front end portion, which is used as, matches dowel pin, and one end and the hole benchmark of the second leading-off rods 5 draw The rear end face connection of end 4, the other end of the second leading-off rods 5 install the second orienting reflex ball out.

As shown in figure 3, a kind of axis hole benchmark scene for measure for precision visual using above-mentioned tooling is quickly drawn Method includes the following steps:

Step 1: establishing tooling coordinate system；

The axis benchmark lead front end surface of tooling is drawn with axis benchmark and hole benchmark draws tooling hole benchmark exit First 4 leading portion annular shape table top is respectively the XOY plane of two pieces tooling coordinate system, and the hole of axis benchmark lead or hole benchmark draw The intersection point of the axis and datum plane with dowel pin of tooling hole benchmark lead 4 is coordinate origin O out, orienting reflex ball The line of subpoint of the centre of sphere on datum plane and origin O are coordinate system X-axis, and subpoint, axis benchmark are directed toward by origin in direction The axis with dowel pin that the hole of lead or hole benchmark draw tooling hole benchmark lead 4 is coordinate system Z axis, and direction is by original Point is directed toward orienting reflex ball direction.

Step 2: D coordinates value of the calibration orienting reflex ball centre of sphere under tooling coordinate system；

Accurate Calibration goes out the orienting reflex ball centre of sphere under respective tooling coordinate system on metering type high accuracy three coordinate machine D coordinates value.

Step 3: tooling is quickly drawn at mounting shaft hole benchmark scene；

Benchmark extraction tooling is installed on the reference axis or datum hole of tested mechanical part.

Step 4: measurement；

The space coordinate of the fixed direction reflective ball centre of sphere is measured using precision visual measuring system；Make to draw tooling rotating around axis The hole of benchmark lead or hole benchmark draw the axis rotation with dowel pin of tooling hole benchmark lead 4, utilize vision essence Close measuring system measures directional lighting ball, then rotary tooling, then measures, until tooling rotates a circle.

Step 5: data processing；

Data processing is carried out using the 3 d space coordinate of fixed direction reflective ball and its coordinate value under tooling coordinate system, is asked Solve three-dimensional coordinate of the tooling coordinate origin O in the case where measuring coordinate system.Specifically comprise the following steps:

(1) plane normal vector (A, B, C) is obtained；

If it is (X that benchmark, which draws space coordinate of the fixed direction reflective ball in the case where measuring coordinate system in the entire rotary course of tooling,_m1, Y_m1,Z_m1)、(X_m2,Y_m2,Z_m2)、…、(X_mn,Y_mn,Z_mn) (n >=4), coordinate value of the fixed direction reflective ball under tooling coordinate system be (X_a,0,Z_a), above-mentioned coordinate value is obtained by second step；

By fixed direction reflective ball centre of sphere point coordinate measurement process it is found that all the points in the same plane, if its plane equation is AX+BY+CZ+D=0；By (X_mi,Y_mi,Z_mi) (i=1,2 ..., n, n >=4) bring into equation constitute Simultaneous Equations, utilize minimum Square law can solve plane equation parameter (A, B, C, D), and then can get plane normal vector (A, B, C)；

(2) central coordinate of circle (X is calculated_c, Y_c, Z_c)；

By fixed direction reflective ball centre of sphere point coordinate measurement process it is found that all the points are on the same circle, if its equation is (X- X_c)²+(Y-Y_c)²+(Z-Z_c)²=R², unknown parameter (X can be solved by bringing all the points coordinate into equation_c, Y_c, Z_c) and R.

Utilize vector (A, B, C) and coordinate (X_c, Y_c, Z_c) one, space mistake (X can be obtained_o, Y_o, Z_o) and direction vector be The linear equation of (A, B, C), this straight line are the Z axis of tooling coordinate system, linearly uncompensation distance Z_a, work can be acquired Coordinate value (X of the coordinate origin O in the case where measuring coordinate system_o, Y_o, Z_o)。

Claims

1. An on-site quick extraction tool for shaft and hole benchmarks for visual precision measurement, including a shaft benchmark extraction tool and a hole benchmark extraction tool; the shaft benchmark extraction tool includes a shaft benchmark extraction end, a first extraction rod and a first extraction rod. Directional reflection ball; wherein, the shaft reference leading end (1) is a metal circular ring, the inside of the shaft reference leading end (1) is a matching hole, the inner diameter of which is matched with the shaft size, and the front end face is the reference plane; The first lead-out rod (2) is in the shape of "√" with the short side placed horizontally, one end of the first lead-out rod is connected with one end of the shaft reference lead-out end, and the other end is installed with a first directional reflection ball (3).

2. A kind of on-site quick extraction tooling for shaft hole reference for visual precision measurement according to claim 1, characterized in that: the hole reference extraction tooling comprises a hole reference extraction end (4), a second extraction rod (5) and the second directional reflection ball (6), the reference lead-out end (4) of the hole is a stepped circular truncated cone, the diameter of the front end is smaller than the diameter of the rear end, the front end part is used as a matching pin, and one end of the second lead-out rod (5) is connected to the hole The rear end face of the reference lead-out end (4) is connected, and the other end of the second lead-out rod (5) is installed with a second directional reflection ball.

3. an extraction method based on the fast extraction tooling of the shaft hole benchmark for visual precision measurement according to any one of claims 1-2, comprising the steps:

The first step: establish a tooling coordinate system;

The second step: mark the three-dimensional coordinate value of the center of the directional reflection ball in the tooling coordinate system;

Step 3: Install the shaft hole datum to quickly lead out the tooling on site;

Step 4: measure;

Step 5: Data processing.

4. A method of drawing out according to claim 3, characterized in that: in the step of establishing a tooling coordinate system, the front end face of the shaft reference drawing end of the tooling and the hole reference drawing the tooling hole reference drawing end with the shaft reference (4) The front circular table surface is the XOY plane of the two tooling coordinate systems, respectively, the axis of the axis of the shaft reference lead-out end or the hole of the hole reference lead-out tooling hole reference lead-out end (4) The axis of the mating pin and the reference plane intersect It is the origin O of the coordinate system, and the connection line between the projection point of the center of the directional reflection ball on the reference plane and the origin O is the X axis of the coordinate system, and the direction points from the origin to the projection point. The axis of the mating pin of the hole reference lead-out end (4) is the Z axis of the coordinate system, and the direction points from the origin to the direction where the directional reflection ball is located.

5. A method of drawing out according to claim 3, characterized in that: in the step of marking the three-dimensional coordinate value of the center of the directional reflection sphere in the tooling coordinate system, the orientation is accurately calibrated on a metrology-type high-precision three-coordinate machine The three-dimensional coordinate value of the center of the reflection ball in the respective tooling coordinate system.

6 . The extraction method according to claim 3 , characterized in that: in the step of installing the shaft hole benchmark on-site rapid extraction tooling, the benchmark extraction tool is installed on the benchmark shaft or benchmark hole of the mechanical component under test. 7 .

7. A method of drawing out according to claim 3, characterized in that: in the measuring step, the space coordinates of the center of the directional reflective sphere are measured by a visual precision measuring system; Rotate the axis of the mating pin of the hole or hole reference lead-out end (4) of the tool hole reference lead-out end, measure the directional light-emitting ball with a vision precision measurement system, rotate the tool, and measure again until the tool rotates once.

8. A kind of extraction method according to claim 3, it is characterized in that: described data processing step, utilizes the space three-dimensional coordinate of the directional reflective ball and its coordinate value under the tooling coordinate system to carry out data processing, and solves the tooling The three-dimensional coordinates of the origin O of the coordinate system in the measurement coordinate system.

9. A kind of extraction method according to claim 3, is characterized in that: described data processing step, specifically comprises the following steps:

(1) Obtain the plane normal vector (A, B, C);

Assume that the space coordinates of the directional reflective ball in the measurement coordinate system during the entire rotation process of the reference extraction tooling are (X _m1 , Y _m1 , Z _m1 ), (X _m2 , Y _m2 , Z _m2 ), …, (X _mn , Y _mn ) ,Z _mn )(n≥4), the coordinate value of the directional reflective ball in the tooling coordinate system is (X _a ,0,Z _a );

From the process of measuring the coordinates of the center point of the directional reflective ball, it can be known that all points are in the same plane, and the plane equation is set as _AX + _BY + _CZ +D=0; 2,...,n,n≥4) into the equation to form a simultaneous equation system, solve the plane equation parameters (A, B, C, D), and obtain the plane normal vector (A, B, C);

(2) Calculate the coordinates of the center of the circle (X _c , Y _c , Z _c );

From the process of measuring the coordinates of the center point of the retroreflective ball, it can be known that all points are on the same circle, and the equation is set as (XX _c ) ² +(YY _c ) ² +(ZZ _c ) ² =R ² , and the coordinates of all points are The unknown parameters (X _c , Y _c , Z _c ) and R can be solved by entering the equation;

(3) Calculate the coordinate value (X _o , Y _o , Z _o ) of the origin O of the working coordinate system in the measurement coordinate system;

Using the vector (A, B, C) and the coordinates (X _c , Y _c , Z _c ) to obtain a straight line equation in space through (X _o , Yo , Z _o ₎ and the vector direction is (A, B, C), The straight line is the Z axis of the tooling coordinate system, and the distance Z _a is compensated along the straight line direction to obtain the coordinate values (X _o , Y _o , Z _o ) of the origin O of the working coordinate system in the measurement coordinate system.