A method for testing the adjustment of a turning mirror of a vertical camera with optical axis

Abstract

The application discloses a kind of optical axis vertical camera's folding mirror's adjustment test method, this method is based on three different height conversion station pins of customization, combined with three-dimensional coordinate transformation, adjustment target value is reversed, inverse solution folding mirror's space position and posture, realizes the precision adjustment and test of optical axis vertical camera folding mirror.Through three coordinate actual measurement data shows, for the translation amount control of optical axis vertical camera folding mirror within ±0.015mm, inclination amount control within ±2 seconds.Result shows, this test method has universality, and measurement precision is high and the characteristics, also better overcome the problem of traditional folding mirror adjustment test method, repeatedly disassembles, and the problem of insufficient test precision, realize the high-efficiency assembly and high-precision measurement of folding mirror in optical axis vertical camera main light path.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of space remote sensor, and particularly relates to a folding mirror adjustment and testing method of an optical axis vertical camera. BACKGROUND

[0002] With the pursuit of high resolution of space remote sensor, in recent years, optical axis vertical cameras are gradually applied in the field of space remote sensor design. The folding mirror is an important component in the main light path of the optical axis vertical camera. In the adjustment process of the optical axis vertical camera, the precise positioning of the folding mirror is an important procedure.

[0003] The existing measurement technologies mainly include the following: a) relying on the theodolite, only the horizontal angle and the pitch angle of the folding mirror coated reflecting surface can be measured, and the precise positioning of the folding mirror space coordinates cannot be realized; b) using the laser tracker to directly measure, which is limited by the installation position and size of the folding mirror, as shown in FIG. 1, the structure often interferes and blocks, and the test precision cannot meet the requirements of precise measurement and precise adjustment. Figure 1 SUMMARY

[0004] The technical problem of the application is to overcome the shortcomings of the prior art, provide a folding mirror adjustment and testing method of an optical axis vertical camera, and solve the problems of complicated process and insufficient precision in the optical precise adjustment and testing process of the folding mirror of the optical axis vertical camera, so as to realize the efficient assembly and high-precision measurement of the space position of the folding mirror in the main light path of the optical axis vertical camera.

[0005] In order to solve the above technical problems, the application discloses a folding mirror adjustment and testing method of an optical axis vertical camera, which comprises the following steps:

[0006] Seven rotating station pins, i.e., rotating station pin M1, rotating station pin M2, rotating station pin M3, rotating station pin M4, rotating station pin M5, rotating station pin M6 and rotating station pin M7, are installed on the mounting plate of the folding mirror;

[0007] Target balls P1, P2, P3, P4, P5, P6 and P7 are respectively installed on the rotating station pins M1, M2, M3, M4, M5, M6 and M7;

[0008] A three-coordinate measuring machine is used to measure the mirror surface and the seven target balls of the folding mirror, and a folding mirror coordinate system C1 is constructed according to the measurement results, and seven nominal points in the folding mirror coordinate system C1 are determined;

[0009] According to the theoretical position relationship R0 of the mirror surface of the folding mirror model and the four corner points of the rectangular mirror surface in the optical design model, the theoretical coordinates A 10 , A 20 , A​30 and A 40 ;

[0010] According to the relationship R2 of the mirror surface M, the four corner points of the rectangular mirror surface and the seven nominal points in the coordinate system C1 of the fold mirror, the coordinates T1-T7 of the seven target spheres in the theoretical coordinate system C0 are calculated through the best fitting transformation of three-dimensional space points, straight lines and planes; and T1-T7 are taken as the adjustment target values;

[0011] Using three laser trackers, the difference ΔT1-ΔT3 between the coordinate values of the target spheres P1-P3 in the theoretical coordinate system C0 and the adjustment target values T1-T3 is obtained through tracking measurement; and the fold mirror is quickly positioned according to the difference ΔT1-ΔT3;

[0012] Using a single laser tracker, the difference ΔT1-ΔT7 between the coordinate values of the target spheres P1-P7 in the theoretical coordinate system C0 and the adjustment target values T1-T7 is obtained through tracking measurement; and the final calculation of the spatial position and posture of the fold mirror is performed according to the difference ΔT1-ΔT7;

[0013] Through the measurement of the coordinate values of the target spheres P1-P7, combined with the position relationship R3 of the target spheres P1-P7, the mirror surface M of the fold mirror and the four corner points A1-A4 of the rectangular mirror surface, the spatial position and posture of the fold mirror are inversely solved through the best fitting transformation of three-dimensional space points, straight lines and planes.

[0014] In the above optical axis vertical camera fold mirror adjustment test method, a coordinate measuring machine is used to measure the mirror surface of the fold mirror and the seven target spheres, and the fold mirror coordinate system C1 is constructed according to the measurement results, and the seven nominal points in the fold mirror coordinate system C1 are determined, including:

[0015] The mirror surface M of the fold mirror, the four edge points L1-L4 of the rectangular mirror surface, and the seven target spheres S1-S7 are measured in the CMM coordinate system;

[0016] The centers of the spheres S1-S7 are fitted to obtain the center coordinates P1(X1, Y1, Z1), P2(X2, Y2, Z12), P3(X3, Y3, Z3), P4(X3, Y3, Z3), P5(X3, Y3, Z3), P6(X3, Y3, Z3) and P7(X7, Y7, Z7) of the seven target spheres in the coordinate system of the coordinate measuring machine;

[0017] Through the space intersection calculation of the edge points L1-L4 and the mirror surface M, the coordinates A1-A4 of the four corner points of the rectangular mirror surface and the coordinates (X0, Y0, Z0) of the intersection S of the diagonal L14 and the diagonal L23 are obtained;

[0018] Taking the coordinates (X0, Y0, Z0) of the intersection S as the origin O1, taking the plane where the mirror surface of the folding mirror is located as the X1O1Y1 plane, taking the direction of the fitting center line of the line segment L14 and the line segment L23 as the X1 axis, and taking the direction of the fitting center line of the line segment L12 and the line segment L34 as the Y1 axis, a folding mirror coordinate system C1 is established according to the right-hand rule: O 1- X1Z1Y1;

[0019] P1 (X1, Y1, Z1), P2 (X2, Y2, Z12), P3 (X3, Y3, Z3), P4 (X3, Y3, Z3), P5 (X3, Y3, Z3), P6 (X3, Y3, Z3) and P7 (X7, Y7, Z7) are taken as nominal points of the folding mirror coordinate system C1.

[0020] In the folding mirror installation and adjustment test method of the optical axis vertical camera, the heights of the transfer station pin P1 and the transfer station pin P7 are consistent, which is H1; the heights of the transfer station pin P3, the transfer station pin P4 and the transfer station pin P5 are consistent, which is H2; the heights of the transfer station pin P2 and the transfer station pin P6 are consistent, which is H3; H1 < H2 < H3; in the Y direction: the transfer station pin P1 and the transfer station pin P7 are located on the same straight line, which is recorded as a first transfer station pin group; the transfer station pin P3, the transfer station pin P4 and the transfer station pin P5 are located on the same straight line, which is recorded as a second transfer station pin group; the transfer station pin P4 and the transfer station pin P5 are located on the same straight line, which is recorded as a third transfer station pin group; the first transfer station pin group, the second transfer station pin group and the third transfer station pin group are sequentially arranged along the positive direction of the X; wherein, the plane where the mounting plate is located is the XOY plane.

[0021] In the folding mirror installation and adjustment test method of the optical axis vertical camera, the transfer station pin is installed on the mounting plate of the folding mirror in a threaded connection manner.

[0022] In the folding mirror installation and adjustment test method of the optical axis vertical camera, the target ball is installed on the transfer station pin through a neodymium magnet.

[0023] The present application has the following advantages:

[0024] (1) The present application discloses a folding mirror installation and adjustment test method of an optical axis vertical camera, which can accurately install the folding mirror of the optical axis vertical camera to a spatial position and attitude close to the optical design theory, and can be applied to the installation and adjustment test process of a certain military reconnaissance remote sensing satellite high-resolution camera.

[0025] (2) The present application discloses a folding mirror installation and adjustment test method of an optical axis vertical camera, which can accurately measure the spatial position and attitude of the folding mirror assembly of the optical axis vertical camera through the measurement means, solves the difficult problem of high risk, low efficiency and insufficient precision of the traditional test method for the folding mirror of the optical axis vertical camera, and has successfully guided the installation and adjustment test work of multiple high-resolution earth observation cameras with optical axis vertical. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is a schematic diagram of a position of a turning mirror in an optical path in an embodiment of the present application;

[0027] Figure 2 is a schematic diagram of installation of a turning station pin in an XOY plane in an embodiment of the present application;

[0028] Figure 3 is a schematic diagram of installation of a turning station pin in an XOZ plane in an embodiment of the present application;

[0029] Figure 4 is a schematic diagram of installation of a turning station pin and a target ball in an embodiment of the present application;

[0030] Figure 5 is a schematic diagram of a principle of establishment of a coordinate system of a turning mirror by a three-coordinate measurement in an embodiment of the present application;

[0031] Figure 6 is a schematic diagram of a principle of rapid approach to a theoretical value assembly in an embodiment of the present application;

[0032] Figure 7 is a schematic diagram of a principle of measurement of a spatial position and posture of a turning mirror of a single laser tracker in an embodiment of the present application. DETAILED DESCRIPTION

[0033] To make the purpose, technical scheme and advantages of the present application clearer, the disclosed embodiments of the present application will be described in further detail below with reference to the drawings.

[0034] One of the core ideas of the present application is that, in order to solve the problem that a traditional theodolite test cannot realize precise positioning of a spatial coordinate of a turning mirror of an optical axis vertical camera, and the problem that a direct measurement of a traditional laser tracker is interfered by a structure and has insufficient test precision, a method for assembly and adjustment test of a turning mirror of an optical axis vertical camera is proposed. The method is based on three different height turning station pins customized, combined with three-dimensional coordinate transformation, and performs assembly and adjustment target value back calculation to inversely solve the spatial position and posture of the turning mirror, so as to realize precise assembly and adjustment and test of the turning mirror of the optical axis vertical camera. The three-coordinate actual measurement data show that the translation amount of the turning mirror of the optical axis vertical camera is controlled within ±0.015 mm, and the inclination amount is controlled within ±2 seconds. The results show that the test method has the characteristics of strong universality and high measurement precision, and also better overcomes the problems of repeated disassembly and assembly and insufficient test precision of a traditional turning mirror assembly and adjustment test method.

[0035] In the embodiment, the assembly and adjustment test method of the turning mirror of the optical axis vertical camera includes:

[0036] Step 1, install seven turning station pins on the mounting plate of the turning mirror: turning station pin M1, turning station pin M2, turning station pin M3, turning station pin M4, turning station pin M5, turning station pin M6 and turning station pin M7.

[0037] In this embodiment, as shown in Figure 2 and Figure 3 , the turning station pin M1, the turning station pin M2, the turning station pin M3, the turning station pin M4, the turning station pin M5, the turning station pin M6 and the turning station pin M7 are arranged on the mounting plate of the turning mirror. The height of the turning station pin P1 and the turning station pin P7 is consistent, which is H1; the height of the turning station pin P3, the turning station pin P4 and the turning station pin P5 is consistent, which is H2; the height of the turning station pin P2 and the turning station pin P6 is consistent, which is H3; H1<H2<H3. In the Y direction: the turning station pin P1 and the turning station pin P7 are located on the same straight line, which is recorded as the first turning station pin group; the turning station pin P3, the turning station pin P4 and the turning station pin P5 are located on the same straight line, which is recorded as the second turning station pin group; the turning station pin P4 and the turning station pin P5 are located on the same straight line, which is recorded as the third turning station pin group; the first turning station pin group, the second turning station pin group and the third turning station pin group are arranged in turn along the positive direction of X, staggered in height, and arranged in a stepped manner; wherein the XOY plane refers to the plane on which the mounting plate is located.

[0038] Step 2, install the target ball P1, the target ball P2, the target ball P3, the target ball P4, the target ball P5, the target ball P6 and the target ball P7 on the turning station pin M1, the turning station pin M2, the turning station pin M3, the turning station pin M4, the turning station pin M5, the turning station pin M6 and the turning station pin M7 respectively.

[0039] In this embodiment, as shown in Figure 4 , each target ball is installed on the corresponding turning station pin through a neodymium magnet. Each turning station pin is installed on the mounting plate of the turning mirror in a threaded connection manner. Through the best fitting matching of the target ball positioning, instead of repeated measurement of the turning mirror, it plays a key role in the mounting and adjustment of the turning mirror.

[0040] Step 3, use a three-coordinate measuring machine to measure the mirror surface of the turning mirror and the seven target balls, and construct the turning mirror coordinate system C1 according to the measurement results, and determine the seven nominal points in the turning mirror coordinate system C1.

[0041] In this embodiment, as shown in Figure 5As shown, the mirror surface M of the folding mirror, the four edge points L1 to L4 of the rectangular mirror, and the spherical surfaces S1 to S7 of the seven target spheres are measured in the CMM coordinate system. By fitting the center of the spheres S1 to S7, the center coordinates of the seven target spheres are obtained as follows: P1(X1,Y1,Z1), P2(X2,Y2,Z12), P3(X3,Y3,Z3), P4(X3,Y3,Z3), P5(X3,Y3,Z3), P6(X3,Y3,Z3), and P7(X7,Y7,Z7) in the coordinate system of the coordinate measuring machine. Furthermore, by solving the spatial intersection calculation between the edge points L1 to L4 and the mirror surface M, the coordinates A1 to A4 of the four corner points of the rectangular mirror, and the coordinates (X0,Y0,Z0) of the intersection point S of diagonals L14 and L23 are obtained. Finally, with the coordinates (X0, Y0, Z0) of the intersection point S as the origin O1, the plane containing the mirror surface as the X1O1Y1 plane, the direction of the fitting center line of line segment L14 and line segment L23 as the X1 axis, and the direction of the fitting center line of line segment L12 and line segment L34 as the Y axis, a coordinate system C1:O is established according to the right-hand rule. 1- X1Z1 Y1; Meanwhile, P1(X1,Y1,Z1), P2(X2,Y2,Z12), P3(X3,Y3,Z3), P4(X3,Y3,Z3), P5(X3,Y3,Z3), P6(X3,Y3,Z3) and P7(X7,Y7,Z7) are used as nominal points of the folding mirror coordinate system C1.

[0042] Step 4: Based on the theoretical positional relationship R0 between the mirror surface of the folding mirror model and the four corner points of the rectangular mirror in the optical design model, determine the theoretical coordinates A of the four corner points of the rectangular mirror in the theoretical coordinate system C0. 10 A 20 A 30 and A 40 .

[0043] Step 5: Based on the coordinates of the mirror surface M, the four corner points of the rectangular mirror, and the relationship R2 of the seven nominal points under the coordinate system C1 of the rotating mirror, the coordinates T1 to T7 of the seven target spheres under the theoretical coordinate system C0 are calculated through the best fitting transformation of three-dimensional space points, lines, and planes; T1 to T7 are used as the assembly target values.

[0044] Step 6, as follows Figure 6 As shown, three laser trackers were used to obtain the difference ΔT1~ΔT3 between the coordinates of the target spheres P1~P3 in the theoretical coordinate system C0 and the target values ​​T1~T3 in the assembly and adjustment by actual tracking and measurement; based on the difference ΔT1~ΔT3, the folding mirror was quickly positioned.

[0045] Step 7, as follows Figure 7As shown, using a single laser tracker, the coordinate values of the target balls P1-P7 in the theoretical coordinate system C0 are measured, and the difference values AT1-AT7 between the measured values and the set values T1-T7 are obtained; and the spatial position and posture of the turning mirror are calculated according to the difference values AT1-AT7.

[0046] In step 8, the coordinate values of the target balls P1-P7 are measured, and the spatial position and posture of the turning mirror are obtained by combining the three-coordinate measurement of the target balls P1-P7 and the turning mirror, the position relationship R3 of the four corner points A1-A4 of the rectangular mirror surface, and the best fitting transformation of three-dimensional space points, lines and planes.

[0047] In summary, the application discloses a method for assembling, adjusting and testing a turning mirror of an optical axis vertical camera, and the method is used for precise assembling, adjusting and testing of multiple turning mirrors of optical axis vertical cameras.

[0048] Although the application has been disclosed with the above preferred embodiments, it is not intended to limit the application, and any person skilled in the art can make possible changes and modifications to the technical solutions of the application without departing from the spirit and scope of the application.

[0049] The contents not described in detail in the specification of the application belong to the known technology of the person skilled in the art.

Claims

1. A method of testing the alignment of a fold mirror of an optical axis vertical camera, characterized in that, Comprise: Install seven rotating station pins on the mounting plate of the folding mirror: rotating station pin M1, rotating station pin M2, rotating station pin M3, rotating station pin M4, rotating station pin M5, rotating station pin M6 and rotating station pin M7; Install target ball P1, target ball P2, target ball P3, target ball P4, target ball P5, target ball P6 and target ball P7 on rotating station pin M1, rotating station pin M2, rotating station pin M3, rotating station pin M4, rotating station pin M5, rotating station pin M6 and rotating station pin M7 respectively; Use a three-coordinate measuring machine to measure the mirror surface of the folding mirror and the seven target balls, and construct folding mirror coordinate system C1 according to the measurement results, and determine the seven nominal points under folding mirror coordinate system C1; According to the theoretical position relationship R0 between the mirror surface of the fold mirror model in the optical design model and the four corner points of the rectangular mirror surface, the theoretical coordinates A of the four corner points of the rectangular mirror surface in the theoretical coordinate system C0 are determined 10 , A 20 , A 30 , and A 40 ; According to the relationship R2 between the coordinates of the mirror surface M, the four corner points of the rectangular mirror surface and the seven nominal points under folding mirror coordinate system C1, the coordinates T1-T7 of the seven target balls under theoretical coordinate system C0 are calculated through three-dimensional space point, straight line and plane best fitting transformation; T1-T7 are used as the adjustment target value; Use three laser trackers to obtain the difference ΔT1-ΔT3 between the coordinate values of target balls P1-P3 under theoretical coordinate system C0 and the adjustment target value T1-T3 through tracking measurement; according to the difference ΔT1-ΔT3, the folding mirror is quickly positioned; Use a single laser tracker to obtain the difference ΔT1-ΔT7 between the coordinate values of target balls P1-P7 under theoretical coordinate system C0 and the adjustment target value T1-T7 through tracking measurement; according to the difference ΔT1-ΔT7, the final calculation of the spatial position and attitude of the folding mirror is carried out; Through the measured coordinate values of target balls P1-P7, combined with the three-coordinate measurement of target balls P1-P7 and the position relationship R3 of the mirror surface M of the folding mirror and the four corner points A1-A4 of the rectangular mirror surface, the spatial position and attitude of the folding mirror are inversely solved through three-dimensional space point, straight line and plane best fitting transformation; Use a three-coordinate measuring machine to measure the mirror surface of the folding mirror and the seven target balls, and construct folding mirror coordinate system C1 according to the measurement results, and determine the seven nominal points under folding mirror coordinate system C1, comprising: Measure the mirror surface M of the folding mirror, the four edge points L1-L4 of the rectangular mirror surface, and the seven spherical surfaces S1-S7 under the CMM coordinate system; Carry out spherical center fitting on the spherical surfaces S1-S7 to obtain the spherical center coordinates P1-P7 of the seven target balls under the three-coordinate measuring machine coordinate system; Through the space intersection calculation of the edge points L1-L4 and the mirror surface M, the coordinates A1-A4 of the four corner points of the rectangular mirror surface and the coordinates (X0, Y0, Z0) of the intersection S of the diagonal L14 and the diagonal L23 are obtained; With the coordinates (X0, Y0, Z0) of the intersection point S as the origin O1, with the plane where the mirror surface of the turning mirror is located as the X1O1Y1 plane, with the direction of the fitting center line of the line segment L14 and the line segment L23 as the X1 axis, and with the direction of the fitting center line of the line segment L12 and the line segment L34 as the Y1 axis, a turning mirror coordinate system C1:O 1- X1Z1Y1; The spherical center coordinates P1-P7 of the seven target balls under the three-coordinate measuring machine coordinate system are used as the nominal points of the folding mirror coordinate system C1.

2. The method of claim 1, wherein: The heights of rotating station pin M1 and rotating station pin M7 are consistent, which are H1; the heights of rotating station pin M3, rotating station pin M4 and rotating station pin M5 are consistent, which are H2; the heights of rotating station pin M2 and rotating station pin M6 are consistent, which are H3; H1 Rotating station pin M1 and rotating station pin M7 are located on the same straight line in the Y direction, which is recorded as the first rotating station pin group; Rotating station pin M3, rotating station pin M4 and rotating station pin M5 are located on the same straight line, which is recorded as the second rotating station pin group; The rotating pin M4 and the rotating pin M5 are located on the same straight line, and are denoted as a third rotating pin group; The first rotating pin group, the second rotating pin group and the third rotating pin group are sequentially arranged along the positive direction of X; wherein, the plane where the mounting plate is located is XOY plane.

3. The method of claim 1, wherein: The rotating pin is installed on the mounting plate of the folding mirror in a threaded connection mode.

4. The method of claim 1, wherein: The target ball is installed on the rotating pin through a neodymium magnet.

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