阅读说明：本技术 一种用于环形薄壁工件的双传感器测量系统以及测量方法 (Double-sensor measuring system and measuring method for annular thin-wall workpiece ) 是由 陈远流 胡朋 高智远 居冰峰 于 2021-08-31 设计创作，主要内容包括：本发明属于高精度测量技术领域,特指一种用于环形薄壁工件的双传感器测量系统以及测量方法。包括：XY定位平台,具有X方向移动的X向驱动平台以及Y方向移动的Y向驱动平台；旋转台,设置在XY定位平台上,用于Z向旋转；手调台,设置在旋转台上,且具有装夹环形薄壁工件的工件载具,用于微调环形薄壁工件的位置；Z向驱动平台,用于Z方向移动；两个传感器调节装置,安装在Z向驱动平台上；以及两个距离传感器,安装在传感器调节装置上,且距离传感器的光路相互对齐。本发明通过两个距离传感器测量环形薄壁工件的中心线与旋转台转轴轴线之间的偏移距离以及偏移角度,并通过手调台消除,从而提高工件的测量精度。(The invention belongs to the technical field of high-precision measurement, and particularly relates to a double-sensor measurement system and a measurement method for an annular thin-wall workpiece. The method comprises the following steps: an XY positioning stage having an X-direction driving stage moving in an X direction and a Y-direction driving stage moving in a Y direction; the rotating platform is arranged on the XY positioning platform and used for rotating in the Z direction; the manual adjusting platform is arranged on the rotating platform, is provided with a workpiece carrier for clamping the annular thin-wall workpiece and is used for finely adjusting the position of the annular thin-wall workpiece; the Z-direction driving platform is used for moving in the Z direction; the two sensor adjusting devices are arranged on the Z-direction driving platform; and two distance sensors installed on the sensor adjusting device, and optical paths of the distance sensors are aligned with each other. According to the invention, the offset distance and the offset angle between the central line of the annular thin-wall workpiece and the axis of the rotating shaft of the rotating table are measured by two distance sensors and eliminated by manually adjusting the table, so that the measurement precision of the workpiece is improved.)

1. A dual sensor measurement system for an annular thin-walled workpiece, comprising:

an XY positioning platform, which is provided with an X-direction driving platform (102) moving in the X direction and a Y-direction driving platform (101) moving in the Y direction;

a rotating table (103) which is arranged on the XY positioning platform and used for Z-direction rotation;

the manual adjusting platform (105) is arranged on the rotating platform (103), is provided with a workpiece carrier for clamping the annular thin-walled workpiece (106), and is used for finely adjusting the position of the annular thin-walled workpiece (106);

a Z-direction driving platform (109) used for moving in the Z direction;

two sensor adjusting devices are arranged on the Z-direction driving platform (109) and used for adjusting the position of the distance sensor (107); and

and two distance sensors (107) are arranged on the sensor adjusting device, and the light paths of the distance sensors (107) are mutually aligned and used for measuring the distance from the distance sensors (107) to the inner wall and the outer wall of the annular thin-walled workpiece (106).

2. The dual-sensor measurement system for the annular thin-walled workpiece of claim 1, wherein: the distance sensor (107) is a dispersive confocal sensor.

3. The dual-sensor measurement system for the annular thin-walled workpiece of claim 1, wherein: also included is a standard ball (116) mountable on the hand-adjusting station (105) for aligning the optical paths of the two distance sensors (107).

4. The dual-sensor measurement system for the annular thin-walled workpiece of claim 1, wherein: the manual adjusting table (105) comprises an X-direction translation fine adjusting assembly used for X-direction movement, a Y-direction translation fine adjusting assembly used for Y-direction movement, an X-direction inclination table (110) used for rotating around the X direction and a Y-direction inclination table (111) used for rotating around the Y direction.

5. The dual-sensor measurement system for the annular thin-walled workpiece of claim 1, wherein: the sensor adjusting device comprises a Z-direction translational fine adjusting component (112) used for Z-direction movement, an X-direction translational fine adjusting component (113) used for X-direction movement, a Z-direction angle fine adjusting component (114) used for rotating around the Z direction and a Y-direction angle fine adjusting component (115) used for rotating around the Y direction.

6. A double-sensor measuring method for an annular thin-wall workpiece, which is characterized in that the double-sensor measuring system for the annular thin-wall workpiece is based on any one of claims 1 to 5 and comprises the following steps:

the first step is as follows: mounting an annular thin-walled workpiece (106) to a workpiece carrier;

the second step is that: moving the XY positioning platform to enable the annular thin-walled workpiece (106) to move to the position below the two distance sensors (107); moving a Z-direction driving platform (109) to enable two distance sensors (107) to move to the thin wall where the horizontal section a of the annular thin-wall workpiece (106) is located;

the third step: by passingControlling the rotation of the rotating platform (103) and the translation of the X-direction driving platform (102) to measure the annular thin-walled workpiece (106), recording the reading of the distance sensor (107), and calculating the eccentric coordinate O of the circle center of the annular thin-walled workpiece (106) at the horizontal section a relative to the rotation axis of the rotating platform (103) according to the geometric relation_a(x_a，y_a，z_a)；

The fourth step: moving the Z-direction driving platform (109) to enable the two distance sensors (107) to move to the thin wall where the horizontal section b of the annular thin-wall workpiece (106) is located;

the fifth step: by controlling the rotation of the rotating platform (103) and the translation of the X-direction driving platform (102), the annular thin-wall workpiece (106) is measured, the reading of the distance sensor (107) is recorded, and the eccentric coordinate O of the circle center of the annular thin-wall workpiece (106) at the horizontal section b relative to the rotating axis of the rotating platform (103) is calculated according to the geometric relation_b(x_b，y_b，z_b)；

And a sixth step: calculating the inclination angle alpha of the central axis of the annular thin-wall workpiece (106) on the YZ plane and the inclination angle beta on the XZ plane according to the eccentric coordinates of the centers of the circles of the horizontal section a and the horizontal section b, wherein the formula is as follows:

the seventh step: and respectively adjusting the freedom degrees of the rotation of the manual adjusting platform (105) around the X axis and the Y axis according to the inclination angles alpha and beta, so that the central axis of the annular thin-wall workpiece (106) is parallel to the rotation axis of the rotating platform (103), and the inclination angle adjustment of the annular thin-wall workpiece (106) is measured.

Eighth step: controlling the rotation of the rotating platform (103) and the translation of the X-direction driving platform (102) to measure the annular thin-wall workpiece (106), recording the reading of the dispersive confocal sensor (108), and calculating the eccentric coordinate (X) of the circle center of the annular thin-wall workpiece (106) at the horizontal section b relative to the rotation axis according to the geometric relation_b1，y_b1，z_b) (ii) a Then according to x_b1And y_b1The eccentric distance in the direction of X, Y can be eliminated by adjusting the manual adjusting platform (105), and then the middle of the annular thin-wall workpiece (106) is enabledThe spindle coincides with the rotation axis of the rotating table (103) to realize centering.

7. The dual sensor measurement system for an annular thin-walled workpiece of claim 6, further comprising a ninth step of: the Z positioning platform (110) is required to be controlled to translate and the rotating platform (103) is required to rotate so as to realize the spiral scanning measurement of the double displacement sensors on the annular thin-wall workpiece (106).

8. The dual-sensor measuring system for the annular thin-walled workpiece according to claim 6, characterized in that before measuring the annular thin-walled workpiece (106), the optical path alignment operation of two displacement sensors (107) is first performed:

firstly, a standard ball (116) is arranged on a manual adjusting table (105), and the standard ball (116) is moved between two displacement sensors by moving an X-direction driving platform (102), a Y-direction driving platform (101) and a Z-direction driving platform (109);

secondly, the light paths of the two displacement sensors are aligned to the center of a standard ball (116) by adjusting a sensor adjusting device;

finally, the standard ball (116) is removed.

Technical Field

The invention belongs to the technical field of high-precision measurement, and particularly relates to a double-sensor measurement system and a measurement method for an annular thin-wall workpiece.

Background

The annular thin-wall workpiece is an indispensable component in national defense, aviation, information electronics and optical systems, and the cylindricity, the wall thickness difference, the appearance error and the like of the annular thin-wall workpiece greatly influence the performance of the system. The accurate and stable measurement of the wall surface of the annular thin-wall workpiece is realized, so that the improvement of the processing precision of the annular thin-wall workpiece is an important means for improving the system performance.

In a single-sensor measuring system of an annular thin-wall workpiece, a positioning error of a rotating table is an important error source, and the positioning error of the rotating table directly causes a splicing error of measured data of inner and outer walls of the annular thin-wall workpiece, so that the measured data cannot accurately reflect a wall thickness difference.

In the double-sensor measuring system, the eccentricity and inclination error of the workpiece to be measured and the deviation of the measuring light path of the double sensors directly cause the measuring error of the annular thin-wall workpiece, and the error is more obvious and critical in the precision measuring system. How to effectively restrain and decompose the eccentricity and inclination angle errors of the annular thin-wall workpiece and the deviation of a measuring light path of the double sensors by using the double sensors for measurement has more important significance for the precise measurement of the annular thin-wall workpiece.

Disclosure of Invention

The invention aims to provide a double-sensor measuring system and a measuring method with simple structure and high precision.

The purpose of the invention is realized as follows:

a dual sensor measurement system for an annular thin-walled workpiece, comprising:

an XY positioning stage having an X-direction driving stage moving in an X direction and a Y-direction driving stage moving in a Y direction;

the rotating platform is arranged on the XY positioning platform and used for rotating in the Z direction;

the manual adjusting platform is arranged on the rotating platform, is provided with a workpiece carrier for clamping the annular thin-wall workpiece and is used for finely adjusting the position of the annular thin-wall workpiece;

the Z-direction driving platform is used for moving in the Z direction;

the two sensor adjusting devices are arranged on the Z-direction driving platform and used for adjusting the positions of the distance sensors; and

and the two distance sensors are arranged on the sensor adjusting device, and the light paths of the distance sensors are mutually aligned and are used for measuring the distance from the distance sensors to the inner wall and the outer wall of the annular thin-wall workpiece.

Preferably, the distance sensor is a dispersive confocal sensor.

Preferably, a standard ball is also included, mountable on the hand-set table, for alignment of the optical paths of the two distance sensors.

Preferably, the manual adjustment table comprises an X-direction translation fine adjustment assembly for X-direction movement, a Y-direction translation fine adjustment assembly for Y-direction movement, an X-direction inclination table for rotating around an X direction and a Y-direction inclination table for rotating around a Y direction.

Preferably, the sensor adjusting device comprises a Z-direction translational fine adjusting component for Z-direction movement, an X-direction translational fine adjusting component for X-direction movement, a Z-direction angle fine adjusting component for rotation around the Z-direction, and a Y-direction angle fine adjusting component for rotation around the Y-direction.

A double-sensor measuring method for an annular thin-wall workpiece is based on the double-sensor measuring system for the annular thin-wall workpiece, and comprises the following steps:

the first step is as follows: mounting an annular thin-walled workpiece to a workpiece carrier;

the second step is that: moving the XY positioning platform to enable the annular thin-walled workpiece to move to the position below the two distance sensors; moving the Z-direction driving platform to enable the two distance sensors to move to the thin wall where the horizontal section a of the annular thin-wall workpiece is located;

the third step: the rotation of the rotary table and the translation of the X-direction driving platform are controlled to measure the annular thin-wall workpiece, the reading of the distance sensor is recorded, and the eccentric coordinate O of the circle center of the annular thin-wall workpiece at the horizontal section a relative to the rotation axis of the rotary table is calculated according to the geometric relationship_a(x_a，y_a，z_a)；

The fourth step: moving the Z-direction driving platform to enable the two distance sensors to move to the thin wall where the horizontal section b of the annular thin-wall workpiece is located;

the fifth step: tong (Chinese character of 'tong')The rotation of the rotary table and the translation of the X-direction driving platform are controlled, the annular thin-wall workpiece is measured, the reading of the distance sensor is recorded, and the eccentric coordinate O of the circle center of the annular thin-wall workpiece at the horizontal section b relative to the rotation axis of the rotary table is calculated according to the geometric relationship_b(x_b，y_b，z_b)；

And a sixth step: calculating the inclination angle alpha of the central shaft of the annular thin-wall workpiece on a YZ plane and the inclination angle beta of the central shaft of the annular thin-wall workpiece on an XZ plane according to the eccentric coordinates of the centers of the horizontal sections a and b, wherein the formula is as follows:

the seventh step: and respectively adjusting the degree of freedom of the hand adjusting table rotating around the X axis and the Y axis according to the inclination angles alpha and beta, so that the central axis of the annular thin-wall workpiece 106 is parallel to the rotation axis of the rotating table, and the inclination angle adjustment of the annular thin-wall workpiece is realized.

Eighth step: controlling the rotation of the rotary table and the translation of the X-direction driving platform to measure the annular thin-wall workpiece, recording the reading of the dispersion confocal sensor, and calculating the eccentric coordinate (X) of the circle center of the annular thin-wall workpiece at the horizontal section b relative to the rotation axis according to the geometric relationship_b1，y_b1，z_b) (ii) a Then according to x_b1And y_b1The eccentric distance in the direction of X, Y can be eliminated by adjusting the manual adjusting table, so that the central axis of the annular thin-wall workpiece is superposed with the rotation axis of the rotating table, and the centering is realized.

The ninth step: the Z positioning platform translation and the rotating platform rotation are controlled to realize the spiral scanning measurement of the double-displacement sensor on the annular thin-wall workpiece.

Preferably, before measuring the annular thin-wall workpiece, the optical path alignment operation of the two displacement sensors is firstly carried out:

firstly, a standard ball is arranged on a manual adjusting table, and the standard ball is moved between two displacement sensors by moving an X-direction driving platform, a Y-direction driving platform and a Z-direction driving platform;

secondly, the light paths of the two displacement sensors are aligned to the center of the standard ball by adjusting the sensor adjusting device;

finally, the standard ball is removed.

Compared with the prior art, the invention has the outstanding and beneficial technical effects that:

1. according to the invention, the offset distance and the offset angle between the central line of the annular thin-wall workpiece and the axis of the rotating shaft of the rotating table are measured by two distance sensors and eliminated by manually adjusting the table, so that the measurement precision of the workpiece is improved.

2. The invention uses the double-dispersion confocal sensor to measure the inner wall and the outer wall of the annular thin-wall workpiece, can improve the measurement efficiency, overcomes the splicing error of the measurement data of the inner wall and the outer wall in the measurement of a single sensor, has very high measurement precision, and is suitable for the measurement of high-precision parts.

3. The invention can reduce the inclination angle between the central line of the annular thin-wall workpiece and the axis of the rotating shaft of the rotating table to +/-0.1 degree through manually adjusting the table, and can also reduce the eccentricity between the central line of the annular thin-wall workpiece and the axis of the rotating shaft of the rotating table to submicron order.

4. According to the invention, through the standard ball and the sensor adjusting device, the deviation of the double-sensor measuring light path to the micron order can be reduced, the alignment precision of the detecting light path is effectively improved, and the measuring precision of the displacement sensor is further improved.

Drawings

Fig. 1 is a schematic diagram of the structure of a dual sensor measurement system of the present invention.

Fig. 2 is a schematic diagram of the alignment of the optical paths of the dual sensors of the present invention.

FIG. 3 is a schematic diagram of the centering of an annular thin-walled workpiece.

FIG. 4 is a schematic illustration of the movement of a dual displacement sensor to the thin wall of an annular thin-walled workpiece.

FIG. 5 is a schematic diagram of a dual displacement sensor for helical scan measurement of an annular thin-walled workpiece.

The reference numerals in the figures denote the meanings:

a 101-Y direction driving mechanism; a 102-X direction drive mechanism; 103-rotating table; 104-manually adjusting the installation position; 105-manual tuning; 106-ring-shaped thin-walled workpiece; 107-distance sensors; 108-a sensor mount; 109-Z direction driving platform; a 110-X direction tilt table; a 111-Y direction tilt table; 112-Z translational fine adjustment component; 113-X direction translation fine adjustment components; 114-Z direction angle fine adjustment component; 115-Y direction angle fine adjustment component; 116-Standard ball.

Detailed Description

The invention is further described below with reference to specific examples:

as shown in fig. 1, a dual-sensor measuring system for a ring-shaped thin-walled workpiece includes an XY positioning stage, a rotating stage 103, a manual adjusting stage 105, a Z-direction driving stage 109, two sensor adjusting devices, and two distance sensors 107.

The XY positioning platform is provided with an X-direction driving platform 102 moving in the X direction and a Y-direction driving platform 101 moving in the Y direction, and is mainly used for moving and positioning the annular thin-wall workpiece. The XY positioning platform is provided with a rotating platform 103 used for rotating in the Z direction, the rotating platform 103 is provided with a manual adjusting installation position 104, the manual adjusting installation position 104 is provided with a manual adjusting platform 105, the manual adjusting platform 105 is provided with a workpiece carrier for clamping the annular thin-walled workpiece 106, and the manual adjusting platform 105 is used for finely adjusting the position of the annular thin-walled workpiece 106.

The manual adjustment stage 105 includes an X-direction translational fine adjustment assembly for X-direction movement, a Y-direction translational fine adjustment assembly for Y-direction movement, an X-direction tilt stage 110 for rotation about the X-direction, and a Y-direction tilt stage 111 for rotation about the Y-direction. When the distance sensor 107 measures the offset of the central axis of the annular thin-walled workpiece and the axis of the rotating shaft of the rotating table 103, the structure can not only eliminate the offset in the X direction through the X-direction translation fine-tuning component and eliminate the offset in the Y direction through the Y-direction translation fine-tuning component, but also eliminate the spatial inclination angle of the annular thin-walled workpiece 106 through the X-direction inclination angle table 110 and the Y-direction inclination angle table 111, is suitable for the annular thin-walled workpiece 106 with the central axis and the bottom surface not vertical, and ensures that the central axis of the annular thin-walled workpiece 106 before measurement is the rotating axis of the overlapping rotating table 103, so as to improve the measurement precision.

In this embodiment, the manual adjustment mounting position 104 is a mounting plate fixed at the bottom of the manual adjustment platform 105, and the mounting plate is fixed on the rotation platform 103 by screws. The workpiece carrier is an annular seat, the bottom of the annular thin-wall workpiece 106 is arranged on the inner ring of the annular seat, and clamping is realized through a fastener.

The Z-direction driving platform 109 is used for moving and positioning the distance sensor 107 in the Z direction, two sensor adjusting devices for adjusting the position of the distance sensor 107 are symmetrically arranged on the Z-direction driving platform through the sensor mounting frame 108, and each sensor adjusting device is correspondingly provided with one distance sensor 107.

In this embodiment, the distance sensor 107 is a dispersive confocal sensor, is vertically disposed in the sensor adjustment device, and has a light source emitting light at 90 °, and the light paths of the distance sensor 107 are aligned with each other, so as to measure the distance from the distance sensor 107 to the inner wall and the outer wall of the annular thin-walled workpiece 106, and measure the surface shape, the roundness, the cylindricity, and the like of the annular thin-walled workpiece 106, and the precision thereof is nm level.

Specifically, a sensor adjusting device for adjusting the position of the distance sensor 107 is symmetrically arranged on the Z-direction driving platform 109, and the sensor adjusting device includes a Z-direction translational fine adjusting component 112 for Z-direction movement, an X-direction translational fine adjusting component 113 for X-direction movement, a Z-direction angle fine adjusting component 114 for rotation around the Z-direction, and a Y-direction angle fine adjusting component 115 for rotation around the Y-direction. The sensor adjusting device can adjust the position of the distance sensor 107 in the Z/X direction and the angle of the Z/Y direction, and facilitates the adjustment of the light path of the distance sensor 10.

The present embodiment is further provided with a standard ball 116 having a diameter of 8mm and a processing accuracy of 30nm, which is detachably mounted on the manual adjustment stage 105.

Before measurement, the standard ball 116 is mounted on the manual adjustment table 105, the position of the standard ball 116 is adjusted by adjusting the X-direction driving platform 102, the Y-direction driving platform 101, and the Z-direction driving platform 109, and the position of the optical path of the distance sensor 107 is adjusted by the sensor adjustment device, and when the optical path of the distance sensor 107 is aligned with the center of the standard ball 116, the optical path is aligned. After the light paths are aligned, the standard ball 116 is removed.

In this embodiment, the X-direction driving stage 102, the Y-direction driving stage 101, and the Z-direction driving stage 109 include a servo motor, a screw transmission structure, and a sliding table, and the servo motor drives the sliding table to move linearly through the screw transmission structure, generally, the stroke is within 1000mm, and the precision is in the μm level.

The structures of the X-direction translation fine adjustment assembly, the Y-direction translation fine adjustment assembly, the Z-direction translation fine adjustment assembly 112 and the X-direction translation fine adjustment assembly 113 are similar to the structure of the driving platform, a general manual control lead screw transmission structure drives the sliding table to move linearly, the stroke of the sliding table is in a mm level, and the adjustment precision is in a micrometer level.

The structures of the X-direction inclination angle table 110, the Y-direction inclination angle table 111, the Z-direction angle fine adjustment component 114 and the Y-direction angle fine adjustment component 115 are all similar, and the X-direction inclination angle table, the Y-direction inclination angle table, the Z-direction angle fine adjustment component 114 and the Y-direction angle fine adjustment component 115 all comprise a mounting seat provided with an arc-shaped groove, a rotating block arranged on the arc-shaped bottom surface and a fine adjustment component, wherein the rotating block is arranged on the mounting seat in a rotating mode through the fine adjustment component, so that the rotating block can rotate around the axis of the arc-shaped groove, and angle adjustment is achieved. The angle adjusting range is +/-10 degrees, and the adjusting precision is 0.01 degrees.

A double-sensor measuring method for an annular thin-wall workpiece is based on the double-sensor measuring system for the annular thin-wall workpiece.

Before measuring the annular thin-wall workpiece 106, the optical path alignment operation of the two displacement sensors 107 is firstly carried out:

first, the reference ball 116 is mounted on the manual stage 105, and the X-direction drive table 102, the Y-direction drive table 101, and the Z-direction drive table 109 are moved to move the reference ball 116 between the two displacement sensors. Secondly, the degree of freedom of the sensor adjusting device in the Y direction is adjusted, so that the standard ball 116 is positioned within the measuring range of the two displacement sensors; the X, Z directional freedom of the sensor adjusting device is adjusted to align the optical paths of the two displacement sensors with the center of the standard ball 116. As shown in fig. 2, the alignment of the optical paths of the two displacement sensors 107 is achieved, with the standard ball 116 removed.

Then, starting centering and detecting of the annular thin-wall workpiece, wherein the method comprises the following steps:

the first step is as follows: mounting the annular thin-walled workpiece 106 to a workpiece carrier;

the second step is that: moving the XY positioning platform to enable the annular thin-wall workpiece 106 to move to the position below the two distance sensors 107; then moving the Z-direction driving platform 109 to move the two distance sensors 107 to the thin wall where the horizontal section a of the bottom annular thin-wall workpiece 106 is located, as shown in FIG. 3;

the third step: measuring the annular thin-walled workpiece 106 by controlling the rotation of the rotary table 103 and the translation of the X-direction driving platform 102, recording the reading of the distance sensor 107, and calculating the eccentric coordinate O of the circle center of the annular thin-walled workpiece 106 at the horizontal section a relative to the rotation axis of the rotary table 103 according to the geometric relation_a(x_a，y_a，z_a)；

The fourth step: moving the Z-direction driving platform 109 to enable the two distance sensors 107 to move to the thin wall where the horizontal section b of the top annular thin-wall workpiece 106 is located;

the fifth step: by controlling the rotation of the rotary table 103 and the translation of the X-direction drive platform 102, the annular thin-wall workpiece 106 is measured, the reading of the distance sensor 107 is recorded, and the eccentric coordinate O of the circle center of the annular thin-wall workpiece 106 at the horizontal section b relative to the rotation axis of the rotary table 103 is calculated according to the geometric relation_b(x_b，y_b，z_b)；

And a sixth step: calculating the inclination angle alpha of the central axis of the annular thin-wall workpiece 106 on the YZ plane and the inclination angle beta on the XZ plane according to the eccentric coordinates of the centers of the circles of the horizontal section a and the horizontal section b, wherein the formula is as follows:

the seventh step: according to the inclination angles alpha and beta, the degrees of freedom of the rotation of the manual adjusting platform 105 around the X axis and the Y axis are respectively adjusted, so that the central axis of the annular thin-wall workpiece 106 is parallel to the rotation axis of the rotating platform 103, and the inclination angle adjustment of the annular thin-wall workpiece 106 is realized.

Eighth step: controlling the rotating platform 103 to rotate and the X-direction driving platform 102 to translate to measure the annular thin-wall workpiece 106, recording the reading of the dispersive confocal sensor 108,calculating the eccentric coordinate (x) of the circle center of the annular thin-wall workpiece 106 at the horizontal section b relative to the rotation axis according to the geometric relation_b1，y_b1，z_b) (ii) a The axis of rotation of the rotary table 103 is a reference system of X/Y origin, then according to X_b1And y_b1The eccentric distance in the direction X, Y can be eliminated by adjusting the manual adjustment table 105, and the center axis of the annular thin-walled workpiece 106 is aligned with the rotation axis of the rotary table 103, thereby realizing centering.

The ninth step: as shown in fig. 4, the dual displacement sensor is moved to the thin-wall measurement starting point of the annular thin-wall workpiece 106; as shown in FIG. 5, it is necessary to control the translation of the Z positioning stage 110 and the rotation of the rotary table 103 to realize the spiral scanning measurement of the annular thin-walled workpiece 106 by the dual displacement sensors.

The above embodiments are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereby, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.