WO2023123560A1 - Inner wall measurement system and method based on deep vector height workpiece - Google Patents

Abstract

An inner wall measurement system based on a deep vector height workpiece, comprising: a workpiece seat (108), used for placing a deep vector height workpiece (109); a lateral meter (111), used for measuring the inner sidewall of the deep vector height workpiece (109); an axial meter (112), used for measuring the inner wall and the bottom wall of the deep vector height workpiece (109); and a six-degree-of-freedom motion platform, wherein the workpiece seat (108), the lateral meter (111), and the axial meter (112) are mounted on the six-degree-of-freedom motion platform, the six-degree-of-freedom motion platform is used for driving the workpiece seat (108) to perform six-degree-of-freedom motion relative to the lateral meter (111) or the axial meter (112), the six-degree-of-freedom motion platform comprises a horizontal base (103) and a vertical base (101), the horizontal base (103) is used for mounting the workpiece seat (108), and the vertical base (101) is used for mounting the lateral meter (111) and the axial meter (112).

Description

Inner wall measurement system and measurement method based on deep sagittal workpiece technical field

The invention relates to a method for measuring the overall shape of the inner wall of a deep sagittal height workpiece, in particular to a measurement scheme and a measurement system for measuring the overall shape of the inner wall of a deep sagittal height workpiece by using dual sensors to separately measure different areas of the inner wall and then performing surface splicing.

Background technique

Fukayako workpieces are widely used in precision equipment in aerospace, nuclear physics and other fields. Due to its unique geometry and specific functions, it plays a role that cannot be replaced by other single or assembled parts. At the same time, due to its critical position, during the assembly process of these ultra-precision equipment, its geometric and contour errors will lead to greater assembly errors, thereby reducing the accuracy and reliability of the equipment. Therefore, as our performance requirements for these ultra-precision equipment become more and more stringent, our requirements for Fukayako's workpieces are also getting higher and higher, especially for the geometric dimension accuracy of its inner wall and the quality of its inner contour.

Currently, these Fukayako workpieces are mainly processed by high-precision machine tools, such as Fast Tool Servo (FTS). During the processing, due to the complex control process, processing technology and strict environmental requirements, the processing process is easily affected by abnormal factors such as environment and materials, which will lead to the occurrence of defects in Fukayako workpieces and reduce the processing quality of Fukayako workpieces. Therefore, in order to ensure the geometric dimension accuracy, contour quality and consistency of the deep sagittal workpiece, and to further improve the quality of the workpiece through secondary processing, it is necessary to accurately evaluate the inner wall geometric dimension and inner wall contour quality of the deep sagittal workpiece.

However, the current measurement methods are mainly aimed at measuring the outer wall of deep sagittal workpieces. Existing measurement schemes such as three-coordinate measuring machines cannot measure the bottom of the inner wall due to their large probes and low measurement efficiency. Optical measurement methods have optical path interference or measurement angles are too large etc. cannot meet the requirements of the full-scale measurement of the inner wall. In this regard, a detection scheme that can measure the overall shape of the inner wall of the deep sagittal workpiece is needed.

Contents of the invention

The purpose of the present invention is to provide a deep sagittal workpiece that uses dual sensors to measure different areas of the inner wall separately and then perform surface splicing to meet the demand that the existing measurement method cannot realize the complete measurement of the inner wall of the deep sagittal workpiece. Inner wall full-face measurement scheme and measurement system.

The purpose of the present invention is achieved like this:

Inner wall measurement system based on deep sagittal workpieces, including:

The horizontal base is equipped with an XY positioning platform, and the XY positioning platform includes an X-direction motion platform that moves in the X direction and a Y-direction motion platform that moves in the Y direction; a turntable is set on the XY positioning platform for rotating around the Z direction; the workpiece Seat, arranged on the turntable, for placing deep sagittal workpieces; a vertical base, on which a Z-direction motion platform that moves in the Z direction is provided; a lateral gauge, arranged on the Z-direction motion platform, for measuring the inner wall and side wall of the deep sagittal workpiece; and an axial gauge, which is arranged on the Z-direction motion platform for measuring the inner wall and bottom wall of the deep sagittal workpiece.

Further, it also includes a space posture adjustment device for the first member, which is arranged between the turntable and the workpiece seat, and is used to drive the workpiece seat to rotate around the X direction or/and around the Y direction.

Further, the space attitude adjustment device of the first member includes two first angular positions that rotate around the X direction and the Y direction respectively.

Further, it also includes two second space attitude adjustment devices, which are arranged on the Z-direction motion platform; the lateral gauge and axial gauge are respectively arranged on the corresponding second space attitude adjustment devices; The two spatial attitude adjustment devices are used to drive the lateral gauge and the axial gauge to rotate around the X direction or/and the Z direction.

Further, the space attitude adjustment device of the second member includes two second angular positions that rotate around the X direction and the Z direction respectively.

Further, both the lateral gauge and the axial gauge include a measuring rod and a measuring ball arranged on the end of the measuring rod.

The inner wall measurement method based on the deep sagittal height workpiece is used in the above-mentioned inner wall measurement system based on the deep sagittal height workpiece, comprising: step (1) correcting the lateral gauge and the axial gauge to a vertical state; step (2) correcting the workpiece seat so that The deep sagittal height workpiece is in a horizontal state; step (3) is by making the lateral gauge move against the inner wall side wall of the deep sagittal height workpiece along the generatrix of the deep sagittal height workpiece, to measure the surface shape of the deep sagittal height workpiece inner wall side wall; by making The axial meter moves on the inner wall bottom wall of the deep sagittal workpiece axis along the busbar base of the deep sagittal workpiece to measure the surface shape of the inner wall bottom wall of the deep sagittal workpiece; step (4) splicing the surface shape of the inner wall side wall and the shape of the inner wall bottom wall The complete surface shape of the deep sagittal workpiece is obtained.

Further, the lateral gauge and the axial gauge have measuring balls, by which the measuring balls lean against the inner wall of the deep sagittal workpiece; in the process of step (3), there is a measuring ball track, and there is a measuring ball track on the measuring ball track Point coordinates P _Ai (x ₀ , y _Ai , z _Ai ), there is a slope k _Ai and the corresponding inclination angle θ _Ai of the point relative to the coordinate system; the radius of the measuring ball at the angle θ _Ai is calculated according to the slope k _Ai and the corresponding inclination angle θ _Ai ; According to the one-to-one mapping relationship, the inner wall side wall point coordinates P _{Ai '} (x ₀ ', y _{Ai '} , z _{Ai '} ) of the corresponding point coordinates P _Ai (x ₀ , y _Ai , z _Ai ) can be obtained; Point coordinates P _Ai (x ₀ , y _Ai , z _Ai ) corresponding to the inner wall side wall point coordinates P _Ai '(x ₀ ', y _Ai ', z _Ai ') to obtain the continuous inner wall side wall shape ;

In the process of step (3), in the process of step (3), there is a measuring ball trajectory, and there is a point coordinate P _Bi (x ₀ , y _Bi , z _Bi ) on the measuring ball trajectory, the point is relative to the coordinate system There is a slope k _Bi and the corresponding inclination angle θ _Bi ; calculate the radius of the measuring ball at the angle θ _Bi according to the slope k _Bi and the corresponding inclination angle θ _Bi ; according to the one-to-one mapping relationship, the corresponding point coordinates P _Bi (x ₀ , y _Bi , z _Bi ) inner wall side wall point coordinates P _Bi '(x ₀ ', y _Bi ', z _Bi '); by calculating multiple point coordinates P _Bi (x ₀ , y _Bi , z _Bi ) corresponding inner wall side Wall point coordinates P _Bi '(x ₀ ', y _Bi ', z _Bi '), to obtain the surface shape of the continuous inner wall and side wall.

Further, the step (1) includes the correction of the lateral or axial gauge space inclination based on a standard sphere, which includes the steps of: step (1.1) setting a standard sphere on the workpiece seat; step (1.2) looking for the first benchmark surface; the first datum plane is the center plane on the standard sphere, and the first datum plane is parallel to a certain plane in the three-dimensional coordinate system; step (1.3) drives the lateral gauge or axial gauge against the first On the outer contour of a datum plane, and move linearly along the outer contour of the first datum plane; record the first position where the measured value of the lateral gauge or axial gauge is the smallest during the movement process, and the first position with a certain distance from the first position Two positions, and record minimum measured value and measured value respectively; Step (1.4) calculates according to minimum measured value and measured value the spatial inclination α _A of lateral gauge or axial gauge and first reference axis; Described first reference axis and The first reference plane is set vertically; step (1.5) drives the second component space posture adjustment device to correct the angle difference between the side gauge or axial gauge and the first reference axis according to the value of the space inclination α _A.

Further, the calculation method in step (1.4) includes: during the movement of the lateral gauge or axial gauge, there are first position measurement side Z _A0 O _A0 , second position measurement side Z _An O _An , right triangle O _A Q _n O _An and right triangle O _An T _A P _A , the space inclination α _A is ∠P _A O _An T _A ; wherein, the value of the measuring side Z _A0 O _A0 at the first position is S _A0 , the second position The value of the measuring side Z _An O _An is S _An ; in the right triangle O _A Q _A O _An , the point O _A is the center of the standard sphere, and the point O _An is the measurement of the lateral gauge or axial gauge on the second position Z _An The center of the sphere, the point Q _A is the intersection point of the lateral extension side of point O _A and the vertical extension side of point O _An ; in the right triangle O _An T _A P _A , point P _A is _the lateral gauge or The intersection of the vertical extension side of the measuring ball center of the axial meter and the second position measurement side Z _An O _An , point T _A is the vertical point of point O _An on the side T _A O _A0 ;

Calculate ∠P _A O _An T _A according to formulas (1)-(5); wherein, R is the radius of the standard sphere, and r _A is the radius of the measuring sphere.

O An P A =S An -S A0	(1)
O A O An = R + r A O A O An = R + r A	(2)
O A Q A ＝O A O A0 -Q A O A0 ＝O A O A0 -O An T A ＝R+r A -(S An -S A0 )×cosα A	(3)
Q A O An ＝T A O A0 ＝P A O A0 -P A T A ＝Z An -Z A0 -(S An -S A0 )×sinα A	(4)
|O A O An | 2 ＝|P A Q A | 2 +|Q A O An | 2	(5)

Further, the step (1) also includes, measuring the roundness of the measuring ball in the lateral gauge or axial gauge based on the standard ball, which includes step (1.6) setting the standard ball on the workpiece seat; step (1.7) looking for the first Two datum planes; the second datum plane is the central plane on the standard sphere, and the second datum plane is parallel to a certain plane in the three-dimensional coordinate system; step (1.8) drives the lateral gauge or axial gauge against the set on the outer contour of the second datum plane, and move linearly along the outer contour of the second datum plane; record the first position with the smallest measured value during the movement of the lateral gauge or axial gauge, and a certain distance from the first position The second position of the distance, and record the minimum measured value and the measured value respectively; step (1.9) calculate the radius r _Ai of the measuring ball under different positions according to the minimum measured value and several measured values, and integrate the radius r _Ai of the measuring ball to obtain the measuring ball roundness.

Further, it is characterized in that the calculation method in step (1.9) includes:

There is a right-angled triangle O _A Q _Ai O _Ai during the movement of the lateral gauge or axial gauge, and at the point of the right-angled triangle O _A Q _Ai O _Ai , the point O _A is the center of the measuring ball, and the point O _Ai is the second position Z _Ai Measure the center of the ball at , there is a straight line OA _{Z A0} passing through the point _OA , and the Q _Ai is the perpendicular point of the point _OAi on the straight line _OA Z _A0 ;

Calculate the measurement sphere radius r _Ai according to formulas (6)-(10); wherein, the θ _Ai is ∠O _Ai O _A Q _Ai .

Further, the step (2) includes, based on the corrected lateral gauge or axial gauge, correcting the space inclination of the workpiece seat, which includes: step (2.1) placing a deep sagittal height workpiece on the workpiece seat; step (2.2) Drive the axial gauge to move towards the X direction at the z ₁ ' height in the deep sagittal workpiece, find the point P ₁ ' with the largest measured value, and record its coordinate values (x ₁ ', y ₁ ', z ₁ '); the drive shaft The azimuth moves towards the X direction at the z ₂ 'height of the deep sagittal workpiece, finds the point P ₂ ' with the largest measured value, and records its coordinates (x ₂ ', y ₂ ', z ₂ '); drives the axial gage Move towards the Y direction at the z ₃ ' height in the deep sagittal workpiece, find the point P ₃ ' with the largest measured value, and record its coordinate values (x ₃ ', y ₃ ', z ₃ '); The z ₂ 'height in the sagittal workpiece moves towards the Y direction, find the point P ₄ ' with the largest measured value, and record its coordinate values (x ₄ ′, y ₄ ′, z ₄ ′).

Step (2.3) calculates the inclination angle θ _α of the workpiece seat around the X direction and the inclination angle θ _b around the Y direction according to the formula (11), (12);

Further, the step (4) includes: according to the coordinate relationship between the surface shape of the side wall of the inner wall and the shape of the bottom wall of the inner wall, determine the overlapping area between the two shapes, and the coordinate change matrix of the two measured shapes; Measure the surface shape and carry out coordinate changes to obtain the complete surface shape of the inner wall of the workpiece.

Compared with the prior art, the present invention has outstanding and beneficial technical effects as follows:

This patent combines lateral gauges and axial gauges to measure the inner wall shape of deep sagittal workpieces. The measurement structure and measurement method are not affected by optical fibers, and can achieve the purpose of measurement for deep sagittal workpieces of various sizes. In addition, this patent drives the six-degree-of-freedom motion platform to perform the previous correction of the workpiece seat, lateral gauge, and axial gauge, effectively increasing the accuracy of deep sagittal height workpiece detection.

Description of drawings

Figure 1 is a schematic structural view of the inner wall measurement system.

Fig. 2(a) is a schematic diagram of the correction of the space inclination of the side gauge.

Fig. 2(b) is a schematic diagram of the correction of the spatial inclination of the axial gauge.

Fig. 3(a) is a schematic diagram of measuring the roundness of a ball measured by a lateral gauge.

Fig. 3(b) is a schematic diagram of measuring spherical roundness in the axial gauge.

Fig. 4 is a schematic diagram of measurement results of spherical roundness measurement.

Figure 5(a) is a top schematic view of the lateral gauge when correcting the inclination angle of the workpiece seat space.

Fig. 5(b) is a three-dimensional schematic view of the lateral gauge when correcting the inclination angle of the workpiece seat space.

Fig. 6 is a schematic diagram of the inspection process of the inner wall of the deep-sag workpiece.

Fig. 7(a) is a schematic diagram of the lateral gauge detecting the inner wall surface of a deep sagittal workpiece.

Fig. 7(b) is a schematic diagram of the axial gauge detecting the inner wall surface of a deep sagittal workpiece.

The meanings of the symbols in the figure:

101. Vertical base; 102. Z-direction motion platform; 103. Horizontal base; 104. Y-direction motion platform; 105. X-direction motion platform; 106. Turntable; ; 109, deep sagittal height workpiece; 110, the second member space attitude adjustment device; 111, lateral gauge; 112, axial gauge; 201, standard ball; 202, measuring ball.

Detailed ways

The present invention will be further described below in conjunction with specific embodiment:

The embodiment of the present invention relates to a full-scale measurement scheme and measurement system for deep-sagittal workpiece inner walls that use dual sensors to measure different areas of the inner wall separately and then perform surface splicing. It is suitable for information electronics, aerospace, new energy, biomedical, etc. The field of ultra-precision machining and measuring products as key components.

The inner wall measurement system based on the deep sagittal height workpiece in this embodiment includes:

The workpiece seat 108 is used to place the deep sagittal workpiece 109;

Lateral gauge 111, used for measuring the inner wall and side wall of deep sagittal workpiece 109

Axial meter 112, used for measuring the inner wall and bottom wall of deep sagittal workpiece 109;

A six-degree-of-freedom motion platform, the workpiece seat 108, the lateral gauge 111 and the axial gauge 112 are installed on the six-degree-of-freedom motion platform, and is used to drive the workpiece base 108 to perform six degrees of freedom relative to the lateral gauge 111 or the axial gauge 112. sports.

The six-degree-of-freedom motion platform in this patent includes a horizontal base 103 and a vertical base 101, the horizontal base 103 is used to install the workpiece seat 108, and the vertical base 101 is used to install the lateral gauge 111 and the axial gauge 112 .

Specifically as shown in Figure 1, the horizontal base 103 includes a horizontal base plate, on which there are X-direction motion platform 105, Y-direction motion platform 104, turntable 106, first member space attitude adjustment device 107 and The workpiece seat 108, specifically, the X-direction motion platform 105 is an X-direction slide rail device, and the Y-direction motion platform 104 is a Y-direction slide rail device, for the turntable 106 to be arranged above the Y-shaped slide rail device, They are respectively used to drive the workpiece seat 108 to move towards the X direction, move towards the Y direction, and rotate around the Z direction; the first component space posture adjustment device 107 can be two first angular positions stacked together, and the The workpiece seat 108 is arranged on the first angle stage, and the two first angle stages are respectively used to drive the workpiece seat 108 to rotate around the X direction and the Y direction.

The vertical base 101 is placed on one side of the horizontal base 103, and includes a vertical base plate perpendicular to the horizontal base plate. The vertical base plate is provided with a Z-direction motion platform 102 and two second component space posture adjustment devices 110, The two second component space posture adjustment devices 110 are respectively equipped with the lateral gauge 111 and the axial gauge 112 . The Z-direction motion platform 102 is specifically a Z-direction slide rail device. Since the two second component space posture adjustment devices 110 are installed above the Z-direction slide rail device, the side gauge will be driven at the same time when the Z-direction slide rail device is working. 111 and axial gauge 112 lift, by changing the height position of lateral gauge 111 and axial gauge 112, relatively changing the relative position between workpiece seat 108 and lateral gauge 111 or axial gauge 112, also just realized workpiece seat 108 Z direction adjustment. There are two space attitude adjustment devices 110 for the second member, and the two second member space attitude adjustment devices 110 are respectively used to drive the lateral gauge 111 and the axial gauge 112 to rotate around the Z direction and the X direction, and pass The rotation of the lateral gauge 111 or the axial gauge 112 around the Z direction makes the workpiece rotate relative to it; the second component space attitude adjustment device 110 specifically includes two rotating around the X direction and around the Z direction respectively. The second corner platform. In combination with the vertical base 101 , the horizontal base 103 and the components on the vertical base 101 and the horizontal base 103 , adjustment of the six degrees of freedom of the workpiece seat 108 is realized.

The lateral gauge 111 in this patent reads by abutting against the inner wall of the deep sagittal workpiece 109, and its end is provided with an abutment rod that contacts the inner wall of the deep sagittal workpiece 109. The shape changes to swing or stretch, and the lateral gauge 111 will record the readings of the rod after swinging or stretching under different conditions, so as to reflect the shape of the inner wall and side wall of the workpiece 109 . In the same way, the axial meter 112 in this patent abuts against the bottom wall of the inner wall of the workpiece 109 for reading, and its end is provided with a rod that contacts the inner wall and bottom wall of the workpiece 109, which will change with the shape of the surface of the abutted object For expansion and contraction, the lateral gauge 111 will record the readings of the extension rod under different conditions, so as to reflect the shape of the inner wall and bottom wall of the workpiece 109 . In addition, a measuring ball 202 is provided at the end of the abutment rod, and the measuring ball 202 is used to ensure that the lateral gauge 111 is in smooth contact with the inner wall of the deep sagittal workpiece 109; correspondingly, setting the measuring ball 202 will reverse the lateral gauge 111 and the shaft The reading of the direction gauge 112 starts from the center of circle of the measuring ball 202 to the other end of the pole.

Before measuring the deep sagittal height workpiece 109 in this patent, in order to ensure the accuracy of the measurement, it is necessary to correct the six-degree-of-freedom motion platform so that the workpiece seat 108, the lateral gauge 111 and the axial gauge 112 are all in a vertical level state. After all the corrections are completed, the inner wall measurement of the deep sag workpiece 109109 is performed, and the method includes measuring the deep sag by moving the lateral gauge 111 against the inner wall sidewall of the deep sag workpiece 109 along the generatrix of the deep sag workpiece 109 The surface shape of the workpiece 109 inner wall side wall; by making the axial meter 112 move on the deep sagittal height workpiece 109 axis inner wall bottom wall along the busbar base of the deep sagittal height workpiece 109, measure the surface shape of the deep sagittal height workpiece 109 inner wall bottom wall; splicing The surface shape of the side wall of the inner wall and the bottom wall of the inner wall obtain the complete surface shape of the Fukiyako workpiece 109 . The splicing method can use point cloud splicing algorithm to splice two measured surface shapes.

Therefore, this patent also includes a correction method based on the inner wall measurement of deep sagittal workpiece 109, which includes:

Step (1) correcting the lateral gauge 111 and the axial gauge 112 to a vertical state;

Step (2) Correcting the workpiece seat 108 so that the deep sagittal height workpiece 109 is in a horizontal state.

Wherein, the step (1) includes correcting the space inclination of the lateral gauge 111 or the axial gauge 112 based on the standard sphere 201, which includes;

Step (1.1) standard ball 201 is set on workpiece seat 108;

Step (1.2) searches for the first datum plane; the first datum plane is the center plane on the standard sphere 201, and the first datum plane is parallel to a certain plane in the three-dimensional coordinate system;

Step (1.3) Drive the lateral gauge 111 or the axial gauge 112 against the outer contour of the first reference plane, and move linearly along the outer contour of the first reference plane; record the lateral gauge 111 or the axial gauge The first position Z _A0 with the smallest measured value during the movement of the meter 112, and the second position Z _An at a certain distance from the first position Z _A0 , and record the smallest measured value S _A0 and the measured value S _An respectively;

Step (1.4) Calculate the space inclination α A between the lateral gauge 111 or the axial gauge 112 and the first reference axis according to the minimum measured value _{S A0} and the measured value S _An ; the first reference axis is perpendicular to the first reference plane set up;

Step (1.5) Drive the second component space posture adjustment device 110 to correct the angle difference between the lateral gauge 111 or the axial gauge 112 and the first reference axis according to the value of the spatial inclination α _A.

As shown in Figure 2 (a), taking the correction of the lateral gauge 111 as an example, after the standard ball 201 is set on the workpiece seat 108, the plane corresponding to the movement direction of the gauge is the YZ plane, and the first datum plane is now It is the central plane parallel to the YZ plane in the standard ball 201; by making the lateral gauge 111 abut on its right side and moving towards the Z direction, the first position Z _A0 with the smallest measured value during the movement is found and recorded Its minimum value S _A0 ; then make the lateral gauge 111 continue to move toward the Z direction until the measured value of the lateral gauge 111 is close to the maximum value of its range and then stop, and record the second position Z _An and the corresponding measured value S _An ; The advantage of setting the position where the measured value of the lateral gauge 111 is close to the maximum value of its range as the second position z _An is that the measurement range is increased, which helps to improve the stability of the reading.

After obtaining the minimum measurement value S _A0 and measurement value S _An and the corresponding first position Z _A0 and second position Z _An , the spatial inclination angle α _A between the lateral gauge 111 and the X-axis can be calculated by the Pythagorean law. As shown in Figure 2(a), there are first position measurement side Z _A0 O _A0 , second position measurement side Z _An O _An , right triangle O _A Q _A O during the movement of lateral gauge 111 or axial gauge 112 _An and right-angled triangle O _An T _A P _A , at this time, the space inclination α _A is ∠P _A O _An T _A ; wherein, the value of the measuring side Z _A0 O _A0 at the first position is S _A0 , the second position The value of measuring side Z _An O _An is S _An ;

In the right triangle O _A Q _A O _An , the point O _A is the center of the standard sphere 201, and the point O _An is the center of a certain central plane of the measuring ball 202 of the lateral gauge 111 or axial gauge 112 on the second position Z _An , Point Q _A is the intersection point of the horizontal extension side of point O _A and the vertical extension side of point O _An ;

In the right triangle O _An T _A P _A , the point P _A is the vertical extension side of the center of the measuring ball 202 of the lateral gauge 111 or the axial gauge 112 on the first position Z _An and the second position measuring side Z _An O _An Intersection point, point T _A is the vertical point of point O _An on side T _A O _A0 ;

Then, according to the formulas (1)-(5), calculate ∠P _A O _An T _A by solving equations; wherein, the R is the radius of the standard ball 201, and r _A is the radius of the measuring ball 202, both of which are known quantity.

O An P A =S An -S A0	(1)
O A O An = R + r A	(2)
O A Q A ＝O A O A0 -Q A O A0 ＝O A O A0 -O An T A ＝R+r A -(S An -S A0 )×cosα A	(3)
Q A O An ＝T A O A0 ＝P A O A0 -P A T A ＝Z An -Z A0 -(S An -S A0 )×sinα A	(4)
|O A O An | 2 ＝|O A Q A | 2 + |Q A O An | 2	(5)

After obtaining the space inclination α _A , eliminate the space inclination α _A by adjusting the second space posture adjustment device on the side gauge 111, finally make the driving rod of the side gauge 111 parallel to the X axis on the YZ surface of the standard ball 201, Refer to the side gauge 111 state in FIG. 3 . After the space inclination α _A is eliminated, the readings of the lateral gauge 111 can be kept consistent, thereby improving accuracy.

After the lateral gauge 111 adjusts the spatial inclination α _A between the lateral gauge 111 and the X-axis with the YZ plane as the first reference plane, the spatial inclination α between the lateral gauge 111 and the Z-axis should also be adjusted with the XY as the first reference plane _A , this is because the lateral gauge 111 moves vertically for measurement during the actual working process, so when the lateral gauge 111 is corrected, it is only necessary to adjust the spatial inclination α _A between the lateral gauge 111 and the X-axis and Z-axis That's it. The method of adjusting on the XY plane is the same as that on the YZ plane, and will not be described in this patent.

As shown in Figure 2(b), when correcting the axial gauge 112, the YZ surface of the standard ball 201 is also used as the first reference plane, and the axial gauge 112 is moved in the Y direction above the standard ball 201 to find The first position Y _B0 where the measured value is the smallest during the movement process and record its minimum value S _B0 ; Two positions Y _Bn and corresponding measured values S _Bn ;

In combination with what is shown in FIG. 2( b ), the spatial inclination α _B between the axial gauge 112 and the X-axis is calculated according to formulas (6)-(9). In addition, after adjusting the spatial inclination α _B of the axial gauge 112 with the YZ plane as the first reference plane, the spatial inclination α _B between the axial gauge 112 and the Y axis should be adjusted with the XZ plane as the first reference plane, because the axial During the actual working process, the gauge 112 moves horizontally to measure the deep sagittal height of workpieces. Therefore, when the axial gauge 112 is calibrated, it is only necessary to adjust the spatial inclination angle α _A between the axial gauge 112 and the X-axis and Y-axis. The method of adjusting on the XZ plane is the same as that on the YZ plane, and will not be described in this patent.

O B O Bn = R + r B	(6)
O B Q B ＝O B O B0 -Q B O B0 ＝O B O B0 -O Bn T B ＝R+r B -(S Bn -S B0 )×cosα B	(7)
Q B O Bn ＝T B O B0 ＝P B O B0 -P B T B ＝Y Bn -Y B0 -(S Bn -S B0 )×sinα B	(8)
|O B O Bn | 2 ＝|O B Q B | 2 +|Q B O Bn | 2	(9)

In this embodiment, the spatial inclination of the lateral gauge 111 and the axial gauge 112 can be calculated repeatedly to converge to a smaller threshold, such as 0.1 degrees. The space inclination is adjusted.

Further, the step (1) also includes, based on the standard ball 201, measuring the roundness of the measuring ball 202 in the lateral gauge 111 or the axial gauge 112, which includes the steps of:

(1.6) A standard ball 201 is set on the workpiece seat 108;

(1.7) Find the second datum plane; the second datum plane is the center plane on the standard sphere 201, and the second datum plane is parallel to a certain plane in the three-dimensional coordinate system;

(1.8) Drive the lateral gauge 111 or the axial gauge 112 against the outer contour of the second datum plane, and move linearly along the outer contour of the second datum plane; record the lateral gauge 111 or the axial gauge 112 The first position Z _A0 with the smallest measured value during the movement process, and several second positions Z _Ai at a certain distance from the first position Z _A0 , and record the smallest measured value S _A0 and measured value S _Ai respectively;

(1.9) Calculate the radius r _Ai of the measuring ball 202 at different positions according to the minimum measured value S _A0 and several measured values S _Ai , and integrate the radius r _Ai of the measuring ball 202 to obtain the roundness of the measuring ball 202 .

As shown in Figure 3(a), taking the lateral gauge 111 as an example, the plane corresponding to the movement direction of the lateral gauge 111 is also the YZ plane. At this time, the midline plane parallel to the YZ plane on the standard ball 201 is the second reference On the surface, by making the lateral gauge 111 abut on its right side and move towards the Z direction, find the first position Z _A0 with the smallest measured value during the movement and record its minimum value S _A0 ; then make the lateral gauge 111 continue Move toward the Z direction until the measured value of the lateral gauge 111 is close to the maximum value of its range and then stop, and record the second position Z _Ai and the corresponding measured value S _Ai .

At this time, there is a right-angled triangle O _A Q Ai O _Ai during the movement of the lateral gauge 111 or the axial gauge 112. At the point of the right-angled triangle O _A Q _{Ai O Ai} , the point O _A is the center of a certain center plane of the measuring ball 202 , the point O _Ai is the center of the measuring ball 202 at the second position Z _Ai , there is a straight line O _A Z _A0 passing through the point O _A , and the Q _Ai is the vertical point of the point O _Ai on the straight line O _A Z _A0 ;

Calculate measuring ball 202 radius r _Ai according to formula (10)-(14); Wherein, described θ _Ai is ∠O _Ai O _A Q _Ai , and R is standard ball 201 radius, and r _Ai is lateral gauge 111 measuring ball 202 contacts The radius at the point, θ _Ai is the angle of the contact point of the measuring ball 202 compared to the initial point, the radius r _Ai of the lateral gauge 111 at the angle θ _Ai can be obtained by solving the equation, and by integrating multiple second positions Z _Ai , To obtain a complete and continuous roundness profile of the measuring ball 202 .

Since the lateral gauge 111 in this patent is provided with the measuring ball 202, when the lateral gauge 111 detects the deep sagittal workpiece 109, the detected profile is the track of the center of the orbit of the measuring ball 202, not the deep sagittal workpiece 109. Profile; for this purpose, it is necessary to detect the roundness profile of the measuring ball 202 to map the inner wall profile of the deep sagittal workpiece 109 according to the roundness profile of the measuring ball 202 when the lateral gauge 111 detects the deep sagittal workpiece 109 . As shown in Figure 4, under normal circumstances, the lateral gauge 111 only uses about 120 degrees of measuring surface in the measurement process, so when detecting the roundness profile of the measuring ball 202, it only needs to determine about 120 degrees Measuring the surface profile of the ball 202 can meet the needs of the work.

As shown in Figure 3 (b), similar to the lateral gauge 111, when detecting the roundness profile of the axial gauge 112, the plane corresponding to the movement direction of the axial gauge 112 is also the YZ plane, by making the axial gauge 112 112 moves toward the Y direction, finds the first position Y _B0 with the smallest measured value in the moving process, and records its minimum value S _B0 ; then makes the axial meter 112 continue to move toward the Y direction until the measured value of the axial meter 112 is close to its range Stop after the maximum value, and record the second position Y _Bi and the corresponding measured value S _Bi . As shown in Figure 3(b), during the calibration process of the axial gauge 112, there is a right triangle O _B Q _Bi O _Bi , and the roundness profile of the axial gauge 112 measuring ball 202 is obtained by formulas (15)-(19) .

Further, the step (2) includes correcting the spatial inclination of the workpiece seat 108 based on the corrected lateral gauge 111 or axial gauge 112, which includes:

Step (2.1) Place the deep sagittal workpiece 109 on the workpiece seat 108, and the deep sagittal height workpiece 109 is directly placed in the workpiece seat 108;

Step (2.2) Drive the axial gauge 112 to move towards the X direction at the z ₁ ′ height in the deep sagittal height workpiece 109, find the point P ₁ ′ with the largest measured value, and record its coordinate values (x ₁ ′, _y1 ′, _z1 ′ ); drive the axial meter 112 to move towards the X direction at the height of z ₂ ′ in the deep sagittal height workpiece 109, find the point P ₂ ′ with the largest measured value, and record its coordinate value (x ₂ ′, y ₂ ′, z ₂ ′ );

Drive the axial meter 112 to move towards the Y direction at the z ₃ ' height in the deep sagittal height workpiece 109, find the point P ₃ ' with the largest measured value, and record its coordinate value (x ₃ ', y ₃ ', z ₃ '); Drive the axial gauge 112 to move toward the Y direction at the z ₂ ′ height in the deep sagittal height workpiece 109, find the point P ₄ ′ with the largest measured value, and record its coordinate values (x ₄ ′, y ₄ ′, z ₄ ′)

Step (2.3) calculates the inclination angle θ _α of the workpiece seat 108 around the X direction and the inclination angle θ _b around the X direction according to the formulas (20) and (21);

As shown in Figure 5, taking the axial gauge 112 as an example, the points P ₁ ′ and P ₂ ′ correspond to two points on the X-direction generatrix of the deep sagittal workpiece 109, and the inclination angle θ _α readings can be obtained by taking the inverse trigonometric function according to the point coordinates, According to the value of the inclination angle θ _α , adjust the first component space posture adjusting device 107 to realize elimination. Similarly, move the axial gauge 112 toward the Y direction to find the inclination angle θ _b of the workpiece seat 108 around the Y direction to eliminate. The correction method can make the inclination angle θ _α and the inclination angle θ _b converge to a smaller threshold, such as 0.05 degrees, through multiple measurements.

After all the corrections are completed, the inner wall measurement of the deep sagittal workpiece 109 is performed.

Specifically as shown in Figure 6, the measurement direction of the lateral gauge 111 is from the edge to the center, the distance from the measurement end point to the axis of the deep sagittal workpiece 109 is _dA , and the measurement direction of the axial gauge 112 is from the center to the edge of the deep sagittal workpiece 109, The distance between the measurement end point and the axis of the deep sagittal workpiece 109 is d _B , and in general, d _B >d _A .

As shown in Fig. 7, in the process of measuring the inner wall and side wall by the lateral gauge 111, there is a track of the measuring ball 202, and there is a point coordinate P _Ai (x ₀ , y _Ai , z _Ai ) on the track of the measuring ball, There is slope k _Ai and corresponding inclination angle θ _Ai in this point relative coordinate system; According to slope k _Ai and corresponding inclination angle θ _Ai , calculate the radius of measuring ball under the angle of θ _Ai ; According to one-to-one mapping relationship, in conjunction with formula (22)-(24 ), the inner wall side wall point coordinates P _{Ai '} (x _{0 '} , y _Ai ', z _{Ai '} ) of the corresponding point coordinates P _Ai (x ₀ , y _Ai , z _Ai ) can be obtained; by calculating multiple point coordinates P _Ai (x ₀ , y _Ai , z _Ai ) corresponding to the point coordinates P _Ai '(x ₀ ', y _Ai ', z _Ai ') of the inner wall and side wall, to obtain the continuous generatrix trajectory of the inner wall and side wall.

y Ai ′＝y Ai -r Ai cos(θ Ai )	(twenty two)
z Ai ′＝z Ai -r Ai sin(θ Ai )	(twenty three)
θ Ai = arctan(k Ai )	(twenty four)

Similarly, in the process of measuring the bottom wall of the inner wall at the axial meter 112, there is a measuring ball track, and there is a point coordinate P _Bi (x ₀ , y _Bi , z _Bi ) on the measuring ball track, and the relative coordinates of this point There is a slope k _Bi and the corresponding inclination θ _Bi ; according to the slope k _Bi and the corresponding inclination θ _Bi , the radius of the measuring ball at the angle θ _Bi is calculated; according to the one-to-one mapping relationship, the corresponding point coordinates P _Bi (x ₀ , y _Bi , z _Bi ) inner wall side wall point coordinates P _Bi '(x ₀ ', y _Bi ', z _Bi '); by calculating the inner wall corresponding to multiple point coordinates P _Bi (x ₀ , y _Bi , z _BBi ) Side wall point coordinates P _Bi '(x ₀ ', y _Bi ', z _Bi '), to obtain the continuous generatrix trajectory of the inner and bottom walls.

y Bi ′=y Bi -r Bi cos(θ Bi )	(25)
z Bi ′＝z Bi -r Bi sin(θ Bi )	(26)
θ Bi = arctan(k Bi )	(27)

After obtaining the generatrix track of the continuous inner wall side wall and the continuous inner wall bottom wall, the rotating workpiece seat 108 continues to measure to obtain the continuous inner wall side wall and the inner wall bottom wall shape, and according to the inner wall side The surface shape of the wall and the surface shape of the bottom wall of the inner wall are spliced.

In the process of splicing the surface shape of the side wall of the inner wall and the bottom wall of the inner wall, since d _B >d _A , there must be an overlapping area between the side wall of the inner wall and the bottom wall of the inner wall. Specifically, according to the measured surface coordinate axes, the overlapping area between the two surface shapes is determined, and then the overlapping area is stitched through point cloud matching, that is, the coordinates are confirmed according to the change matrix of the two surface shapes Finally, after superimposing the overlapping regions, the coordinates of the entire surface shape of the deep sagittal workpiece 109 are changed to obtain the complete surface shape of the inner wall of the deep sagittal workpiece 109 .

This patent combines the lateral gauge 111 and the axial gauge 112 to measure the inner wall shape of the deep sagittal workpiece 109. The measurement structure and measurement method are not affected by the optical fiber, and the measurement can be achieved for various deep sagittal workpieces 109 of different sizes. Purpose. In addition, this patent drives the six-degree-of-freedom motion platform to perform the previous correction of the workpiece seat 108, the lateral gauge 111, and the axial gauge 112, effectively increasing the accuracy of the detection of the deep sagittal height workpiece 109.

The foregoing embodiments are only preferred embodiments of the present invention, and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made according to the structures, shapes and principles of the present invention shall be covered by the protection of the present invention. within range.

Claims (10)

1. The inner wall measurement system based on deep sagittal workpieces is characterized in that it includes:

   The horizontal base is provided with an XY positioning platform, and the XY positioning platform includes an X-direction motion platform that moves in the X direction and a Y-direction motion platform that moves in the Y direction;

   The turntable is set on the XY positioning platform and is used to rotate around the Z direction;

   The workpiece seat is arranged on the turntable and is used for placing deep sagittal workpieces;

   A vertical base on which a Z-direction motion platform that moves in the Z-direction is provided;

   A lateral gauge, arranged on the Z-direction motion platform, is used to measure the inner wall and side wall of the workpiece with deep sagittal height; and

   The axial gauge is arranged on the Z-direction motion platform and is used for measuring the inner wall and the bottom wall of the workpiece with deep sagittal height.
2. The inner wall measurement system based on deep sagittal height workpiece according to claim 1, characterized in that: it also includes a space posture adjustment device for the first member, which is arranged between the turntable and the workpiece seat, and is used to drive the The workpiece seat rotates around the X direction or/and around the Y direction;

   It also includes two second space attitude adjustment devices, which are arranged on the Z-direction motion platform; the lateral gauge and axial gauge are respectively arranged on the corresponding second space attitude adjustment devices; the second space attitude The adjustment device is used to drive the lateral gauge and axial gauge to rotate around X direction or/and Z direction.
3. The inner wall measurement method based on the deep sagittal height workpiece is used in the inner wall measurement system based on the deep sagittal height workpiece as described in any one of claims 1-2, it is characterized in that, comprising:

   Step (1) Correct the lateral gauge and axial gauge to a vertical state;

   Step (2) correcting the workpiece seat so that the deep sagittal height workpiece is in a horizontal state;

   Step (3) measure the surface shape of the inner wall side wall of the deep sagittal workpiece by making the lateral gauge move against the inner wall side wall of the deep sagittal workpiece along the generatrix of the deep sagittal workpiece; The base moves on the bottom wall of the inner wall of the deep sagittal workpiece axis to measure the surface shape of the inner wall bottom wall of the deep sagittal workpiece;

   Step (4) splicing the surface shape of the side wall of the inner wall and the bottom wall of the inner wall to obtain a complete surface shape of the deep sagittal workpiece.
4. The method for measuring the inner wall based on the deep sagittal height workpiece according to claim 3, wherein: the lateral gauge and the axial gauge have a measuring ball, and the measuring ball leans against the inner wall of the deep sagittal height workpiece; in step (3 ) process, there is a measuring ball trajectory, and there is a point coordinate P _Ai (x ₀ , y _Ai , z _Ai ) on the measuring ball trajectory, and the point has a slope k _Ai and a corresponding inclination angle θ _Ai relative to the coordinate system; according to the slope k _Ai and the corresponding inclination angle θ _Ai are calculated to obtain the radius of the measuring ball at the angle θ _Ai ; according to the one-to-one mapping relationship, the inner wall and side wall point coordinates P _Ai ′ of the corresponding point coordinates P _Ai (x ₀ , y _Ai , z _Ai ) can be obtained (x ₀ ′, y _Ai ′, z _Ai ′); By calculating multiple point coordinates P _Ai (x ₀ , y _Ai , z _Ai ) corresponding inner wall side wall point coordinates P _Ai ′(x ₀ ′, y _Ai ′, z _Ai ′);

   In the process of step (3), there is a measuring ball trajectory, and there is a point coordinate P _Bi (x ₀ , y _Bi , z _Bi ) on the measuring ball trajectory, and the relative coordinate system of this point has a slope k _Bi and a corresponding inclination angle θ _Bi ; According to the slope k _Bi and the corresponding inclination angle θ _Bi , the radius of the measuring ball at the angle θ _Bi is calculated; according to the one-to-one mapping relationship, the inner wall side wall point of the corresponding point coordinate P _Bi (x ₀ , y _Bi , z _Bi ) can be obtained Coordinates P _Bi ′(x ₀ ′,y _Bi ′,z _Bi ′); By calculating multiple point coordinates P _Bi (x ₀ ,y _Bi ,z _BBi ) corresponding inner wall side wall point coordinates P _Bi ′(x ₀ ′, y _Bi ′, z _Bi ′).
5. The inner wall measuring method based on deep sagittal height workpiece according to claim 3, it is characterized in that, comprising: described step (1) comprises carrying out the correction of lateral gauge or axial gauge space inclination based on standard sphere, it comprises the steps:

   Step (1.1) standard ball is set on workpiece seat;

   Step (1.2) finds the first datum plane; The first datum plane is the central plane on the standard sphere, and the first datum plane is parallel to a certain plane in the three-dimensional coordinate system;

   Step (1.3) Drive the lateral gauge or axial gauge against the outer contour of the first reference plane, and move linearly along the outer contour of the first reference plane; record the movement process of the lateral gauge or axial gauge The first position with the smallest measured value, and the second position at a certain distance from the first position, and record the smallest measured value and the measured value respectively;

   Step (1.4) Calculate the space inclination α _A of the side gauge or the axial gauge and the first reference axis according to the minimum measured value and the measured value; the first reference axis is vertically arranged with the first reference plane;

   Step (1.5) Driving the space attitude adjustment device of the second member according to the value of the space inclination α _A to correct the angle difference between the side gauge or axial gauge and the first reference axis.
6. The inner wall measuring method based on deep sagittal height workpiece according to claim 5, is characterized in that, the computing method in step (1.4) comprises:

   During the movement of the lateral gauge or axial gauge, there are the first position measurement side Z _A0 O _A0 , the second position measurement side Z _An O _An , the right triangle O _A Q _A O _An and the right triangle O _An T _A P _A , The spatial inclination α _A is ∠P _A O _An T _A ; wherein, the value of the first position measurement side Z _A0 O _A0 is S _A0 , and the value of the second position measurement side Z _An O _An is S _An ;

   In the right triangle O _A Q _A O _An , the point O _A is the center of the standard sphere, the point O _An is the center of the measuring sphere of the lateral gauge or the axial gauge on the second position Z _An , and the point Q _A is the transverse direction of the point O _A The intersection point of the extended side and the point O _An of the vertically extended side;

   In the right triangle O _An T _A P _A , the point P _A is the intersection point of the vertical extension side of the center of the measuring sphere of the lateral gauge or axial gauge on the first position Z _An and the measuring side Z _An O _An of the second position. T _A is the vertical point of point O _An on the side T _A O _A0 ;

   Calculate ∠P _A O _An T _A according to formulas (1)-(5); wherein, R is the radius of the standard sphere, and r _A is the radius of the measuring sphere.

   O _An P _A =S _An -S _A0 (1) O _A O _An = R + r _A O _A O _An = R + r _A (2) O _A Q _A ＝O _A O _A0 -Q _A O _A0 ＝O _A O _A0 -O _An T _A ＝R+r _A -(S _An -S _A0 )×cosα _A (3) Q _A O _An ＝T _A O _A0 ＝P _A O _A0 -P _A T _A ＝Z _An -Z _A0 -(S _An -S _A0 )×sinα _A (4) |O _A O _An | ² ＝|O _A Q _A | ² + |Q _A O _An | ² (5)
7. The inner wall measuring method based on deep sagittal height workpiece according to claim 3, it is characterized in that, described step (1) also comprises, measure the roundness of measuring ball in lateral gauge or axial gauge based on standard ball, it comprises:

   Step (1.6) standard ball is set on workpiece seat;

   Step (1.7) finds the second datum plane; The second datum plane is the central plane on the standard sphere, and the second datum plane is parallel to a certain plane in the three-dimensional coordinate system;

   Step (1.8) driving the lateral gauge or the axial gauge against the outer contour of the second reference plane, and linearly moving along the outer contour of the second reference plane; recording the movement process of the lateral gauge or the axial gauge The first position with the smallest measured value, and several second positions at a certain distance from the first position, and record the smallest measured value and the measured value respectively;

   Step (1.9) Calculate the radius r _Ai of the measuring ball at different positions according to the minimum measured value and several measured values, and integrate the radius r _Ai of the measuring ball to obtain the roundness of the measuring ball.
8. The inner wall measurement method based on the deep sagittal height workpiece according to claim 7, characterized in that: the calculation method in the step (1.9) comprises:

   There is a right-angled triangle O _A Q _Ai O _Ai during the movement of the lateral gauge or axial gauge, and at the point of the right-angled triangle O _A Q _Ai O _Ai , the point O _A is the center of the measuring ball, and the point O _Ai is the second position Z _Ai Measure the center of the ball at , there is a straight line O _A Z _A0 passing through the point O _A , and the Q _Ai is the vertical point of the point O _Ai on the straight line O _A Z _A0 ;

   Calculate the measurement sphere radius r _Ai according to formulas (6)-(10); wherein, the θ _Ai is ∠O _Ai O _A Q _Ai .

   
9. The inner wall measuring method based on deep sagittal height workpiece according to claim 3, characterized in that, said step (2) includes, based on the corrected lateral gauge or axial gauge, the correction of the workpiece seat space inclination angle includes:

   Step (2.1) placing the deep sagittal workpiece on the workpiece seat;

   Step (2.2) Drive the axial gauge to move towards the X direction at the z ₁ ′ height in the deep sagittal workpiece, find the point P ₁ ′ with the largest measured value, and record its coordinate values (x ₁ ′, y ₁ ′, z ₁ ′ ); drive the axial gauge to move towards the X direction at the z ₂ ′ height in the deep sagittal workpiece, find the point P ₂ ′ with the largest measured value, and record its coordinate values (x ₂ ′, y ₂ ′, z ₂ ′);

   Drive the axial gauge to move towards the Y direction at the z ₃ ′ height in the deep sagittal workpiece, find the point P ₃ ′ with the largest measured value, and record its coordinate values (x ₃ ′, y ₃ ′, z ₃ ′); Move toward the Y direction at the z ₂ ′ height of the gage in the deep sagittal height workpiece, find the point P ₄ ′ with the largest measured value, and record its coordinate values (x ₄ ′, y ₄ ′, z ₄ ′);

   Step (2.3) Calculate the inclination angle θ _α of the workpiece seat around the X direction and the inclination angle θ _b around the Y direction according to formulas (11) and (12).

   
10. The inner wall measurement method based on deep sagittal height workpiece according to claim 3, characterized in that, said step (4) comprises: according to the coordinate relationship between the inner wall side wall surface shape and the inner wall bottom wall surface shape, determine the distance between the two surface shapes From the overlapping area, to the coordinate change matrix of the two measurement surfaces; then coordinate change is performed on the entire measurement surface to obtain the complete surface shape of the inner wall of the deep sagittal workpiece.

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