Optical payload high orthogonality calibration adjustment stage and calibration method

Abstract

The present application relates to the technical fields of precise optical equipment adjustment device, and provides an optical load high orthogonality calibration adjustment platform and a calibration method, the optical load high orthogonality calibration adjustment platform comprises an azimuth rotating platform, a mounting base, a mounting bottom plate, a mounting top plate, a fixed shaft assembly and two adjustment shaft assemblies, one end of the fixed shaft assembly is connected with the mounting bottom plate, the other end is connected with the mounting top plate, and an adjustment gap is arranged between the fixed shaft assembly and the mounting top plate; the adjustment shaft assembly comprises a positive toothed lead screw seat assembly, a negative toothed lead screw seat assembly and a positive and negative toothed lead screw, the positive toothed lead screw seat assembly is arranged on the mounting bottom plate, the negative toothed lead screw seat assembly is arranged on the mounting top plate, and the positive and negative toothed lead screw is adapted to rotate, so that the mounting bottom plate and the mounting top plate are close to or far away from each other.The optical load high orthogonality calibration adjustment platform has the advantages of high adjustment precision, good stability and long-term reliable self-locking function by the synergistic effect of the positive and negative toothed lead screw and the joint bearing.

Description

Technical Field

[0001] This invention relates to the field of precision optical assembly and adjustment equipment, and in particular to a high orthogonality calibration and adjustment stage and calibration method for optical loads. Background Technology

[0002] In the field of space optical communication, the positional relationship between the reference mirror and the pointing beam on the calibration payload is crucial for eliminating geometric installation errors, suppressing dynamic environmental drift, and ensuring optical coaxiality. When the rotation axis of the bottom calibration stage is not properly orthogonal to the reference mirror on the payload, it will directly cause azimuth / pitch rotational motion coupling through the coordinate system distortion effect, resulting in a systematic error in the calibrated "reference mirror-pointing beam" positional relationship. This error is further amplified under thermal deformation, ultimately leading to a significant decrease in on-orbit pointing accuracy.

[0003] In the field of precision optical assembly and adjustment, traditional mechanisms suffer from Z-axis drift during rotation due to bearing clearance or wear of threaded pairs, which disrupts optical orthogonality. High-precision lead screws have weak self-locking force and require additional tightening, while bolt set screws, although self-locking, offer coarse fine-tuning. Bolt set screws also cause plastic deformation of components due to stress concentration at point contact, and the adjustment accuracy decreases after hundreds of cycles of threaded pairs. Flexible platforms lack self-locking functionality. Existing technologies cannot comprehensively address key issues such as rotational decoupling, micron-level precision, high-load self-locking, and long-term wear resistance. Summary of the Invention

[0004] This invention aims to at least solve one of the technical problems existing in related technologies. To this end, this invention proposes an optical load high orthogonality calibration stage, which aims to improve adjustment accuracy and stability, reduce mechanical wear, and achieve long-term reliable self-locking function.

[0005] This invention also proposes a calibration method.

[0006] According to a first aspect of the present invention, an optical payload high orthogonality calibration stage includes:

[0007] Orientation rotary table;

[0008] Mounting base, which is disposed on the orientation rotating platform;

[0009] Mounting base plate, which is disposed on the mounting base;

[0010] The mounting top plate is positioned above the mounting base plate and is opposite to and parallel to the mounting base plate.

[0011] A fixed shaft assembly, one end of which is connected to the mounting base plate and the other end of which is connected to the mounting top plate, and an adjustment gap is provided between the fixed shaft assembly and the mounting top plate;

[0012] Two adjusting shaft assemblies are equidistantly spaced from the fixed shaft assembly along the circumference of the mounting base plate. Each adjusting shaft assembly includes a spur screw seat assembly, a reverse screw seat assembly, and spur and reverse screws. The spur screw seat assembly is located on the mounting base plate, and the reverse screw seat assembly is located on the mounting top plate. The spur and reverse screws include a spur section and a reverse section. The spur section passes through the spur screw seat assembly, and the reverse section passes through the reverse screw seat assembly. The spur and reverse screws are adapted to rotate so that the mounting base plate and the mounting top plate move closer or further apart.

[0013] The optical load high orthogonality calibration stage according to an embodiment of the present invention achieves bidirectional precision adjustment through the synergistic action of the positive and negative threaded screws and the joint bearings. Combined with the support structure distributed at 120° on three points, it effectively eliminates the orthogonality error between the rotating axis and the reference mirror, and has the advantages of improving adjustment accuracy and stability, reducing mechanical wear, and achieving long-term reliable self-locking function.

[0014] According to one embodiment of the present invention, the orthogonal lead screw assembly includes:

[0015] A first joint bearing is disposed on the mounting base plate;

[0016] A first lead screw seat is disposed on the first joint bearing, and the first lead screw seat is provided with a positive thread hole, through which the positive thread segment passes;

[0017] And / or, the reverse thread screw assembly includes:

[0018] A second joint bearing is provided on the mounting top plate;

[0019] The second lead screw seat is located on the second joint bearing and has a reverse thread hole, through which the reverse thread section passes.

[0020] According to one embodiment of the present invention, the adjusting shaft assembly further includes an adjusting knob, which is fixed to one end of the positive and negative threaded rod.

[0021] According to one embodiment of the present invention, the fixed shaft assembly includes:

[0022] A fixed bearing is provided on the mounting base plate;

[0023] A self-aligning shaft, one end of which is connected to the fixed bearing;

[0024] The third joint bearing is located on the mounting top plate, and the end of the self-aligning shaft away from the fixed bearing is connected to the third joint bearing.

[0025] According to one embodiment of the present invention, the optical load high orthogonality calibration adjustment stage further includes a pre-tightening member, one end of which is connected to the mounting base plate and the other end of which is connected to the mounting top plate, and the pre-tightening member causes a tensile pre-tightening force to be formed between the mounting base plate and the mounting top plate.

[0026] According to one embodiment of the present invention, the fixed shaft assembly and the two adjusting shaft assemblies are distributed at 120° on the mounting base plate.

[0027] According to one embodiment of the present invention, the optical load high orthogonality calibration adjustment stage further includes a mounting transition plate, which is disposed on the side of the mounting top plate opposite to the mounting bottom plate.

[0028] According to one embodiment of the present invention, the optical load high orthogonality calibration adjustment stage further includes a tooling plate, which is disposed on the side of the mounting transition plate opposite to the mounting top plate, and the tooling plate is used to mount the load.

[0029] According to a second aspect embodiment of the present invention, the calibration method utilizes the aforementioned optical load high orthogonality calibration stage, and the calibration method includes the following steps:

[0030] Step 1: Place the reference prism at the center of the optical load high orthogonality calibration stage, align the autocollimator with the reference prism so that the imaging crosshair of the reference prism is placed at the center of the field of view of the autocollimator, and record the position of the crosshair, which is the 0-degree position.

[0031] Step 2: Rotate the azimuth rotating stage 90 degrees in the forward direction and fix it so that the imaging crosshair of the reference prism is placed within the field of view of the autocollimator, and make the X-axis position of the crosshair consistent with the X-axis at the 0-degree position. Tighten the positive and negative threaded screws to adjust the Y-axis position of the crosshair and record the position of the crosshair, which is the 90-degree position.

[0032] Step 3: Rotate the azimuth rotating stage 180 degrees in the opposite direction and fix it so that the imaging crosshair of the reference prism is placed within the field of view of the autocollimator, and make the X-axis position of the crosshair consistent with the X-axis at the 0-degree position. Tighten the positive and negative threaded screws to adjust the Y-axis position of the crosshair and record the position of the crosshair, which is -90 degrees.

[0033] Step 4: Rotate the azimuth rotating stage 90 degrees forward again and fix it so that the imaging crosshair of the reference prism is placed within the field of view of the autocollimator, and make the X-axis position of the crosshair consistent with the X-axis at the 0-degree position. Tighten the positive and negative threaded screws to adjust the Y-axis position of the crosshair and record the position of the crosshair. This position is the reset position.

[0034] Step 5: Repeat steps 2, 3, and 4 in sequence, and iterate multiple times until the positional error of the X-axis and Y-axis of the reference prism imaging crosshairs at the 0-degree position, the 90-degree position, and the -90-degree position is less than 3″.

[0035] According to an embodiment of the present invention, the calibration method further includes: after step five, placing the load on the optical load high orthogonality calibration adjustment stage, and then performing steps one to five again.

[0036] The calibration method according to an embodiment of the present invention includes the aforementioned optical load high orthogonality calibration adjustment stage, and therefore has all the technical effects of the aforementioned optical load high orthogonality calibration adjustment stage, which will not be repeated here.

[0037] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is one of the structural schematic diagrams of the optical load high orthogonality calibration and adjustment stage provided in the embodiments of the present invention.

[0040] Figure 2 This is the second schematic diagram of the optical load high orthogonality calibration and adjustment stage provided in the embodiment of the present invention.

[0041] Figure 3 This is a cross-sectional view of the optical load high orthogonality calibration adjustment stage provided in an embodiment of the present invention at the adjustment shaft assembly.

[0042] Figure 4 This is a cross-sectional view of the optical load high orthogonality calibration adjustment stage provided in an embodiment of the present invention at the fixed axis assembly.

[0043] Figure 5 This is a cross-sectional view of the orthogonal screw seat assembly provided in an embodiment of the present invention.

[0044] Figure 6 This is a top view of the optical load high orthogonality calibration adjustment stage provided in this embodiment of the invention at the 0-degree position.

[0045] Figure 7This is a top view of the optical load high orthogonality calibration adjustment stage provided in this embodiment of the invention at a 90-degree position.

[0046] Figure 8 This is a top view of the optical load high orthogonality calibration adjustment stage provided in this embodiment of the invention at the -90 degree position.

[0047] Figure 9 This is a flowchart of the calibration method provided in the embodiments of the present invention.

[0048] Figure label:

[0049] 1. Azimuth rotary table; 2. Mounting base; 3. Mounting base plate; 4. Mounting top plate; 5. Fixed shaft assembly; 51. Fixed bearing; 52. Self-aligning shaft; 53. Third joint bearing; 6. Adjusting shaft assembly; 61. Positive thread screw seat assembly; 611. First joint bearing; 612. First thread screw seat; 62. Reverse thread screw seat assembly; 621. Second joint bearing; 622. Second thread screw seat; 63. Positive and reverse thread screws; 631. Positive thread section; 632. Reverse thread section; 64. Adjusting knob; 7. Preload component; 8. Mounting transition plate; 9. Tooling plate; 200. Autocollimator; 300. Optical load. Detailed Implementation

[0050] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0051] In the description of the embodiments of the present invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of the present invention. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0052] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention based on the specific circumstances.

[0053] In embodiments of the present invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0054] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0055] In existing technologies, the field of precision optical assembly and adjustment has long faced the contradiction of balancing the azimuth and pitch rotation of the adjustment platform, and the difficulty in achieving both adjustment accuracy and self-locking capability. Traditional three-point adjustment structures suffer from Z-axis drift during rotation due to bearing clearance, while lead screw drive mechanisms lack sufficient self-locking force and require additional locking devices. Bolt-set screw solutions, on the other hand, cause plastic deformation of components due to stress concentration at point contact. These defects directly lead to optical calibration deviations, affecting the pointing accuracy and dynamic stability of space optical communication systems.

[0056] Therefore, please refer to the following: Figure 1 , Figure 3 , Figure 4 and Figure 6This application proposes an optical load high orthogonality calibration adjustment stage, including an azimuth rotary stage 1, a mounting base 2, a mounting base plate 3, a mounting top plate 4, a fixed shaft assembly 5, and two adjustment shaft assemblies 6. The mounting base 2 is disposed on the azimuth rotary stage 1, the mounting base plate 3 is disposed on the mounting base 2, and the mounting top plate 4 is disposed opposite to the mounting base plate 3. The fixed shaft assembly 5 connects the mounting base plate 3 and the mounting top plate 4 and forms an adjustment gap. The two adjustment shaft assemblies 6 and the fixed shaft assembly 5 are spaced apart along the circumference of the mounting base plate 3. Each adjustment shaft assembly 6 includes a positive thread screw seat assembly 61, a negative thread screw seat assembly 62, and a positive and negative thread screw 63. The positive thread screw seat assembly 61 is disposed on the mounting base plate 3, the negative thread screw seat assembly 62 is disposed on the mounting top plate 4, and the positive thread section 631 and the negative thread section 632 of the positive and negative thread screw 63 respectively pass through the corresponding screw seat assembly.

[0057] The azimuth rotary table 1 is a mechanical platform that provides basic rotational motion, specifically implemented using a worm gear transmission mechanism, used to support the entire adjustment table for azimuth angle adjustment. The mounting base 2 is a transition component connecting the rotary table and the adjustment structure, specifically implemented using a flange structure, used to transmit rotational torque and maintain structural rigidity. The mounting base plate 3 and mounting top plate 4 are plate-like structures forming parallel adjustment surfaces, arranged opposite each other to form an adjustable-interval parallel mechanism. The fixed shaft assembly 5 is a connecting component with axial constraint capability, specifically implemented using a combination of a self-aligning shaft 52 and a spherical bearing, providing vertical constraint while allowing micron-level displacement compensation. The adjustment shaft assembly 6 is a drive mechanism that generates symmetrical displacement; the positive thread section 631 and the negative thread section 632 of the positive and negative thread screws 63 have opposite thread directions, synchronously changing the distance between the mounting base plate 3 and the top plate through rotation, avoiding rotational coupling caused by unilateral force application.

[0058] Specifically, the azimuth rotary table 1 serves as the basic motion unit, driving the entire adjustment platform to rotate. The mounting base 2 and the mounting base plate 3 form a rigid support system. The fixed shaft assembly 5 connects the base plate and the top plate via the self-aligning shaft 52. Its spherical bearing structure can absorb assembly eccentricity errors, while the reserved adjustment gap allows for slight displacement of the top plate relative to the base plate. Two adjustment shaft assemblies 6 are symmetrically distributed on both sides of the fixed shaft assembly 5. When the positive and negative threaded rods 63 are rotated, the positive thread section 631 drives the base plate to sink, and the negative thread section 632 drives the top plate to rise, forming a symmetrical spacing adjustment. The three-point support layout effectively constrains five of the six degrees of freedom, retaining only the vertical translational degree of freedom. By synchronously adjusting the two positive and negative threaded rods 63, the parallelism of the mounting top plate 4 relative to the base plate can be precisely controlled, eliminating pitch component coupling caused by asymmetrical support during azimuth rotation.

[0059] Through the above technical solution, this application achieves complete decoupling of the rotational and pitching motions of the optical load 300, eliminating the coordinate system distortion effect caused by asymmetrical support. The symmetrical force application during adjustment avoids stress concentration on one side, ensuring the accuracy retention of the threaded pair after long-term use. The synergistic effect of the three-point support topology and the positive and negative threaded rods 63 enables the adjustment table to maintain sub-micron positioning accuracy even under high loads, while achieving reliable self-locking without the need for additional locking devices. The application of spherical bearings and hard alloy materials significantly reduces friction and wear, allowing the adjustment mechanism to maintain stable performance even after repeated use.

[0060] Optionally, the threaded portion of the positive and negative threaded screw 63 is identical except for the opposite thread direction. Specifically, the nominal screw diameter is 20mm, the pitch P is 1mm, the thread is trapezoidal, and the screw material is GCr. 15 The bearing steel undergoes quenching and tempering followed by nitriding to enhance surface hardness. The lead screw seat material is ZCuAl. 10 Fe3 aluminum bronze, with a graphite lining on the threaded portion.

[0061] For example, the overall load capacity of the optical load high orthogonality calibration adjustment table is <30kg, with a pitch adjustment range of ±4° and a pitch adjustment accuracy of 0.3″, and an azimuth adjustment range of ±360° and an azimuth adjustment accuracy of 0.1″. The thread helix angle ≤2° combined with the preload friction damping of the spherical bearing forms a double self-locking mechanism, utilizing the friction angle to achieve static self-locking, and there is no slippage when the load is ≥30kg.

[0062] like Figure 3 and Figure 5 As shown, this application further proposes an orthodontic lead screw seat assembly 61 comprising a first joint bearing 611 and a first lead screw seat 612, and a reverse lead screw seat assembly 62 comprising a second joint bearing 621 and a second lead screw seat 622. The first joint bearing 611 is mounted on the mounting base plate 3, and the first lead screw seat 612 is disposed on the first joint bearing 611 and has an orthodontic hole for the orthodontic section 631 to pass through; the second joint bearing 621 is mounted on the mounting top plate 4, and the second lead screw seat 622 is disposed on the second joint bearing 621 and has a reverse lead hole for the reverse lead section 632 to pass through.

[0063] The first spherical bearing 611 is an adjustable support component with a spherical contact surface, specifically a self-lubricating spherical bearing. Its inner ring is interference-fitted with the first lead screw seat 612, and its outer ring is fixed to the mounting base plate 3. The spherical degree of freedom compensates for the assembly deviation between the lead screw axis and the mounting base plate 3. The positive thread hole is a through hole with a positive thread structure, specifically made of cemented carbide material. Its thread lead matches the positive thread section 631, and precision grinding ensures that the thread pair clearance is less than 0.005 mm, forming a stable force transmission path. The second spherical bearing 621 is structurally symmetrical with the first spherical bearing 611. Its outer ring is fixed to the mounting top plate 4 by bolts, and its inner ring is connected to the second lead screw seat 622. When the reverse thread section 632 rotates, it generates axial displacement while allowing the second lead screw seat 622 to deflect around the axis. The reverse thread hole adopts the opposite thread direction to the positive thread hole. Its inner wall is coated with molybdenum disulfide to reduce the coefficient of friction, and the thread profile is modified to eliminate backlash error.

[0064] Specifically, when the lead screw 63 rotates, the positive thread section 631 drives the first lead screw seat 612 to move axially. At this time, the spherical degree of freedom of the first spherical bearing 611 allows the first lead screw seat 612 to generate a deflection angle of ±4° in the radial plane, eliminating the lead screw axis offset caused by the machining error of the mounting base plate 3. At the same time, the negative thread section 632 drives the second lead screw seat 622 to move in the opposite direction. The spherical support structure of the second spherical bearing 621 ensures that the negative thread hole and the negative thread section 632 always maintain coaxial contact, avoiding unilateral wear of the threaded pair. The first lead screw seat 612 and the second lead screw seat 622 adopt a split design, each independently bearing the axial load of the positive thread section 631 and the negative thread section 632. Through the synergistic action of the double spherical bearings, the rotational motion of the lead screw is converted into a precise relative displacement between the mounting base plate 3 and the mounting top plate 4.

[0065] Through the above technical solution, this application effectively solves the problem of lateral stress concentration in the threaded pair caused by rigid installation of traditional lead screw seats, and eliminates lead screw jamming caused by assembly errors. The double joint bearing structure enables the lead screw seat to maintain a micro-motion accuracy of 0.002 mm even when subjected to loads of over 30 kg.

[0066] This application further proposes that the adjusting shaft assembly 6 also includes an adjusting knob 64, which is fixed to one end of the positive and negative threaded rod 63.

[0067] The adjusting knob 64 is an operating component installed at the end of the lead screw. It can be implemented using a knob structure with anti-slip texture, and is fixedly connected to the lead screw via a keyway or set screw to form a backlash-free transmission. The lead screw 63 is a bidirectional drive component with a positive thread section and a negative thread section. The positive thread section 631 engages with the lead screw seat on the mounting base plate 3, and the negative thread section 632 engages with the lead screw seat on the mounting top plate 4. Rotation causes the mounting base plate 3 and the mounting top plate 4 to move in opposite directions.

[0068] Specifically, when the knob is manually rotated, the positive and negative threaded screws 63 rotate synchronously. The positive thread section 631 drives the positive threaded screw seat of the mounting base plate 3 to move axially, while the negative thread section 632 drives the negative threaded screw seat of the mounting top plate 4 to move in the opposite direction. Because the rigid connection between the knob and the screw eliminates the backlash error in traditional transmission chains, the operator can directly apply precise rotational torque through the knob, ensuring that the mounting base plate 3 and mounting top plate 4 maintain synchronous displacement during adjustment. This structure eliminates intermediate transmission links, avoiding uneven adjustment force caused by tool intervention. Simultaneously, the anti-slip design of the knob enhances the torque transmission efficiency of manual operation, allowing the single adjustment step size to be controlled within the micrometer range.

[0069] like Figure 4 As shown, this application further proposes a fixed shaft assembly 5 including a fixed bearing 51, a self-aligning shaft 52 and a third joint bearing 53. The fixed bearing 51 is disposed on the mounting base plate 3, one end of the self-aligning shaft 52 is connected to the fixed bearing 51, and the third joint bearing 53 is disposed on the mounting top plate 4. The end of the self-aligning shaft 52 away from the fixed bearing 51 is connected to the third joint bearing 53.

[0070] The fixed bearing 51 refers to the support component mounted on the mounting base plate 3, which can be implemented using a deep groove ball bearing or an angular contact bearing, and is used to provide axial positioning for the self-aligning shaft 52 and bear the load in the vertical direction. The third spherical bearing 53 refers to the bearing for the adjustable self-aligning shaft 52 mounted on the mounting top plate 4, which can be implemented using a self-lubricating spherical bearing.

[0071] Specifically, the fixed bearing 51 forms a rigid connection point with the mounting base plate 3, constraining the axial displacement of the self-aligning shaft 52 but releasing its radial degree of freedom. The inner ring of the third joint bearing 53 is interference-fitted with the other end of the self-aligning shaft 52, and the outer ring is fixed to the mounting top plate 4 by bolts. Its spherical sliding pair allows the end of the self-aligning shaft 52 to undergo a slight angular deflection as the position of the mounting top plate 4 changes. This structure creates a rigid constraint chain for the self-aligning shaft 52 in the axial direction, while releasing its degree of freedom in the radial direction through the double spherical fit. This avoids the transmission of bending torque caused by machining errors to the fixed bearing 51 and the third joint bearing 53, thereby reducing stress concentration at the contact surface.

[0072] Through the above technical solution, this application effectively eliminates the assembly eccentricity error between the fixed shaft assembly 5 and the mounting top plate 4, avoids the stress concentration phenomenon caused by rigid connection, reduces the risk of wear on the contact surface of the support component, and ensures the accuracy and stability of the adjustment table during long-term use.

[0073] This application further proposes that the optical load high orthogonality calibration adjustment stage also includes a pre-tightening member 7, one end of which is connected to the mounting base plate 3 and the other end is connected to the mounting top plate 4. The pre-tightening member 7 creates a tensile pre-tightening force between the mounting base plate 3 and the mounting top plate 4.

[0074] The preload element 7 is an elastic element capable of applying axial tensile force, specifically a helical spring or disc spring, with its two ends rigidly fixed to the mounting base plate 3 and mounting top plate 4 respectively. Optionally, the preload element 7 includes multiple springs spaced apart between the mounting base plate 3 and mounting top plate 4. This element eliminates the assembly gap between the fixed shaft assembly 5 and the adjusting shaft assembly 6 by continuously applying tensile force. The tensile preload force refers to a constant tension applied along the separation direction of the mounting base plate 3 and mounting top plate 4, specifically generated by the elastic deformation of the spring. This preload force can continuously counteract the dynamic gap generated by the adjusting shaft assembly 6 during rotation.

[0075] Specifically, the preload 7 rigidly connects the mounting base 3 and the top plate at both ends, forming an axial constraint relationship. When the orientation rotary table 1 drives the mounting base 2 to rotate, the positive and negative threaded rods 63 in the adjusting shaft assembly 6 may experience slight displacement due to the clearance of the thread pair. At this time, the tensile force applied by the preload 7 keeps the mounting top plate 4 and the base plate at a constant distance, avoiding relative positional shifts caused by mechanical clearance.

[0076] Through the above technical solution, this application can effectively eliminate the dynamic gap between the mounting base plate 3 and the mounting top plate 4, suppress the positional displacement of the reference prism caused by mechanical clearance during azimuth rotation, and maintain the orthogonality of the optical path. This preload continues to act after the adjustment shaft assembly 6 completes fine-tuning, preventing the adjustment amount from reverting due to temperature changes or vibration, and ensuring the positional stability of the reference prism during calibration.

[0077] like Figure 6 As shown, this application further proposes that the fixed shaft assembly 5 and the two adjusting shaft assemblies 6 are distributed at 120° on the mounting base plate 3.

[0078] The three-point distribution refers to the geometrical positional relationship of the three support components within the plane of the mounting base plate 3. Specifically, this can be achieved by arranging the fixed shaft assembly 5 and two adjusting shaft assemblies 6 evenly spaced circumferentially around the center of the mounting base plate 3, forming an equilateral triangle structure. This layout ensures that the load and adjustment force are evenly distributed among the support points, avoiding localized stress concentration. The 120° included angle refers to the central angle formed by the lines connecting two adjacent support points to the center of the circle. This can be achieved by machining three mounting holes spaced 120° apart on the mounting base plate 3. This angle design ensures that the force vectors of the three support points are symmetrically distributed within the plane, guaranteeing that the relative displacement between the mounting top plate 4 and the mounting base plate 3 remains purely perpendicular during adjustment.

[0079] Specifically, when the azimuth rotary table 1 drives the mounting base 2 to rotate, the mounting base plate 3 and the mounting top plate 4 are rigidly constrained by the fixed shaft assembly 5. The two adjusting shaft assemblies 6 can be individually adjusted in height via the positive and negative threaded rods 63. The 120° symmetrical distribution of the three points ensures that the adjusting forces of each adjusting shaft assembly 6 form a balanced force system in the plane, eliminating the torque imbalance caused by asymmetrical support. During adjustment, the fixed shaft assembly 5 acts as the main support point to bear the vertical load, while the two adjusting shaft assemblies 6 act as auxiliary support points to synchronously compensate for height deviations. The synergistic effect of the three points ensures that the mounting top plate 4 always translates along the Z-axis, avoiding orthogonal deviations caused by tilting or deflection. When the load rotates, this support structure suppresses the relative torsion between the mounting base plate 3 and the top plate through uniformly distributed contact stress, ensuring the Z-axis positioning accuracy of the reference prism.

[0080] like Figure 2 As shown, this application further proposes that the optical load high orthogonality calibration adjustment stage also includes a mounting transition plate 8, which is located on the side of the mounting top plate 4 away from the mounting bottom plate 3.

[0081] The mounting transition plate 8 refers to the intermediate force-transmitting structure positioned above the mounting top plate 4, and can be made of aluminum alloy or steel sheet. The mounting transition plate 8 is rigidly fixed to the mounting top plate 4 via bolts or locating pins, and positioning reference holes are provided between the mounting transition plate 8 and the tooling plate 9. This structure disperses the concentrated stress applied by the load, preventing localized deformation of the mounting top plate 4 due to direct load-bearing, while simultaneously providing a highly flat mounting reference surface for the tooling plate 9.

[0082] Through the above technical solutions, this application effectively prevents stress concentration and micro-deformation caused by direct load bearing on the top plate, and maintains the flatness and rigidity of the adjustment platform; the coaxiality accuracy of load installation is improved by expanding the reference surface; the split design reduces the difficulty of processing and maintenance, and extends the service life of the adjustment platform.

[0083] This application further proposes that the optical load high orthogonality calibration adjustment stage also includes a tooling plate 9, which is located on the side of the mounting transition plate 8 away from the mounting top plate 4, and the tooling plate 9 is used to install the load.

[0084] The tooling plate 9 refers to a load mounting interface plate independent of the adjustment platform body. It can be made of aluminum alloy or carbon fiber composite material and is connected to the mounting transition plate 8 by bolts. Its function is to provide a customized mounting reference for the load, avoiding rigid coupling caused by directly machining the mounting structure on the adjustment platform body.

[0085] Specifically, the tooling plate 9 and the mounting transition plate 8 form a hierarchical assembly structure. The mounting transition plate 8, acting as an intermediate transition layer, is rigidly connected to the mounting top plate 4 via screws, while the tooling plate 9 is detachably connected to the mounting transition plate 8 via bolts. The load is fixed to the tooling plate 9, and the mounting holes or positioning references of the tooling plate 9 can be customized according to the load interface. When the adjustment table performs azimuth or pitch adjustments, the mounting transition plate 8 transmits the movement of the adjustment table to the tooling plate 9. Simultaneously, the error absorption effect of the intermediate transition layer reduces the assembly stress between the tooling plate 9 and the adjustment table. The tooling plate 9's independent design from the adjustment table body ensures that the flatness error of its mounting surface does not directly affect the positioning accuracy of the adjustment table, thus achieving spatial decoupling between the load mounting interface and the adjustment table's motion accuracy.

[0086] Please refer to the reference. Figures 6 to 8 This application further proposes a calibration method including the following steps: placing a reference prism at the center of an optical load high orthogonality calibration adjustment stage; aligning the autocollimator 200 with the reference prism so that the imaging crosshairs of the reference prism are placed at the center of the field of view of the autocollimator 200; and recording the position of the crosshairs, which is the 0-degree position; rotating the azimuth stage 1 90 degrees clockwise and fixing it so that the imaging crosshairs of the reference prism are placed at the center of the field of view of the autocollimator 200, making the X-axis position of the crosshairs consistent with the X-axis at the 0-degree position; and screwing the positive and negative threaded screws 63 to adjust the Y-axis position of the crosshairs, and recording the position of the crosshairs, which is the 90-degree position; and rotating the azimuth stage 1 180 degrees counterclockwise and fixing it so that the imaging crosshairs of the reference prism are placed at the center of the field of view of the autocollimator 200. Within the field of view of the autocollimator 200, align the X-axis position of the crosshair with the X-axis at the 0-degree position. Tighten the forward and reverse threaded rod 63 to adjust the Y-axis position of the crosshair and record the position of the crosshair, which is the -90-degree position. Rotate the azimuth rotary stage 190 degrees forward again and fix it so that the imaging crosshair of the reference prism is placed at the center of the field of view of the autocollimator 200, aligning the X-axis position of the crosshair with the X-axis at the 0-degree position. Tighten the forward and reverse threaded rod 63 to adjust the Y-axis position of the crosshair and record the position of the crosshair, which is the reset position. Repeat the above steps and iterate multiple times until the positional error of the X-axis and Y-axis of the imaging crosshair of the reference prism at the 0-degree, 90-degree, and -90-degree positions is less than 3″.

[0087] Iterative adjustment refers to the process of repeatedly rotating the azimuth stage and correcting the deviation. Specifically, it can be implemented using closed-loop control logic, allowing adjustment of only a single axial deviation after each rotation to avoid multi-degree-of-freedom coupling interference.

[0088] Specifically, the initial 0-degree position is set as the origin of the reference coordinate system. Constraining the consistency of the X-axis position eliminates the influence of the rotary table's mechanical return error on orthogonality measurement. During ±90-degree rotation, an operation mechanism that only allows adjustment of the Y-axis deviation decomposes the three-dimensional orthogonality error into a single-degree-of-freedom correction problem. The bidirectional displacement characteristics of the positive and negative threaded rods 63 cause relative translation between the mounting top plate 4 and the bottom plate, directly correcting the pitch component deviation caused by the non-orthogonality of the rotation axis and the reference mirror. Through multiple iterative adjustments, mechanical assembly clearances and thermal deformation errors are gradually decoupled, ultimately achieving sub-arcsecond-level optical path orthogonality calibration through position error convergence.

[0089] Through the above technical solution, this application solves the azimuth-pitch-rotation coupling problem caused by the orthogonality deviation between the rotation axis of the calibration adjustment stage and the load reference mirror. The orthogonality deviation of the optical path is converged to the sub-arcsecond level through a multi-angle iterative adjustment mechanism. The synergistic effect of the autocollimator 200 and the positive and negative threaded rods 63 achieves high-precision calibration with a sensorless closed loop, avoiding the complexity and reliability risks introduced by traditional electronic control systems. The operation logic constraining single-axis adjustment effectively isolates multi-degree-of-freedom coupling interference, precisely decoupling mechanical assembly errors and thermal deformation errors in the rotating coordinate system.

[0090] This application further proposes a technical solution to install the actual load onto the adjustment table and perform the full calibration operation again after completing the initial calibration process under no-load conditions.

[0091] The closed-loop calibration mechanism involves adding a loaded re-calibration step after the no-load calibration. Mechanical adjustment eliminates structural deformation caused by the load's own weight and coordinate system offset caused by assembly stress. Specifically, the fine-tuning function of the positive and negative threaded rods 63 dynamically compensates for the deformation of the mounting surface, forcibly aligning the calibration reference with the optical path coordinate system under actual load. Dynamic compensation refers to using the rotation of the positive and negative threaded rods 63 of the adjusting shaft assembly 6 to drive the mounting base plate 3 and mounting top plate 4 closer or further apart, thereby correcting micro-displacements caused by load installation. Specifically, the engagement length of the positive and negative threaded rods 63 can be changed by turning the adjusting knob 64, achieving sub-micron level precision adjustment and ensuring that the orthogonality of the azimuth rotation axis and the optical reference mirror is not affected by external loads.

[0092] Specifically, after establishing the initial coordinate system of the reference prism and autocollimator 200 during the no-load calibration phase, the actual load installation introduces differences in installation angles due to insufficient machining accuracy, flatness, and parallelism of the tooling, resulting in optical path orthogonality deviations. By performing a second calibration step, the positive and negative threaded rods 63 of the adjusting shaft assembly 6 readjust the relative positions of the mounting top plate 4 and the bottom plate under load conditions, compensating for the angular changes caused by machining errors in the mounting tooling. This process eliminates systematic errors through mechanical feedback, ensuring that the calibration reference coordinate system maintains consistency with the optical path spatial relationship under actual load conditions, thereby resolving the orthogonality degradation problem caused by systematic errors.

[0093] Through the above technical solution, this application solves the problem of deteriorated orthogonality caused by systematic errors after load installation, ensuring the consistency between the optical path coordinate system and the calibration reference in the actual working environment. This solution directly corrects the deformation error caused by the load through mechanical adjustment, avoiding the systematic deviation caused by ignoring the load state in traditional methods, thereby ensuring the strict orthogonality between the position and pitch rotation axes of the space optical communication system and the optical reference mirror in a dynamic environment.

[0094] Finally, it should be noted that the above embodiments are only for illustrating the present invention and not for limiting the present invention. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art should understand that various combinations, modifications, or equivalent substitutions of the technical solutions of the present invention do not depart from the spirit and scope of the technical solutions of the present invention and should be covered within the scope of the claims of the present invention.

Claims

1. A calibration method, characterized in that, Based on the high orthogonality calibration stage for optical payloads, the high orthogonality calibration stage for optical payloads includes: Orientation rotary table; Mounting base, which is disposed on the orientation rotating platform; Mounting base plate, which is disposed on the mounting base; The mounting top plate is positioned above the mounting base plate and is opposite to and parallel to the mounting base plate. A fixed shaft assembly, one end of which is connected to the mounting base plate and the other end of which is connected to the mounting top plate, and an adjustment gap is provided between the fixed shaft assembly and the mounting top plate; Two adjusting shaft assemblies are equidistantly spaced from the fixed shaft assembly along the circumference of the mounting base plate. Each adjusting shaft assembly includes a spur screw seat assembly, a reverse screw seat assembly, and a spur screw. The spur screw seat assembly is located on the mounting base plate, and the reverse screw seat assembly is located on the mounting top plate. The spur screw includes a spur section and a reverse section. The spur section passes through the spur screw seat assembly, and the reverse section passes through the reverse screw seat assembly. The spur screw is adapted to rotate so that the mounting base plate and the mounting top plate move closer or further apart. The calibration method includes the following steps: Step 1: Place the reference prism at the center of the optical load high orthogonality calibration stage, align the autocollimator with the reference prism so that the imaging crosshairs of the reference prism are placed at the center of the field of view of the autocollimator, and record the position of the crosshairs, which is the 0-degree position. Step 2: Rotate the azimuth rotary table of the optical load high orthogonality calibration adjustment stage 90 degrees in the forward direction and fix it so that the imaging crosshair of the reference prism is placed within the field of view of the autocollimator, and make the X-axis position of the crosshair consistent with the X-axis at the 0-degree position. Tighten the positive and negative thread screws to adjust the Y-axis position of the crosshair and record the position of the crosshair, which is the 90-degree position. Step 3: Rotate the azimuth rotating stage 180 degrees in the opposite direction and fix it so that the imaging crosshair of the reference prism is placed within the field of view of the autocollimator, and make the X-axis position of the crosshair consistent with the X-axis at the 0-degree position. Tighten the positive and negative threaded screws to adjust the Y-axis position of the crosshair and record the position of the crosshair, which is -90 degrees. Step 4: Rotate the azimuth rotating stage 90 degrees forward again and fix it so that the imaging crosshair of the reference prism is placed within the field of view of the autocollimator, and make the X-axis position of the crosshair consistent with the X-axis at the 0-degree position. Tighten the positive and negative threaded screws to adjust the Y-axis position of the crosshair and record the position of the crosshair. This position is the reset position. Step 5: Repeat steps 2, 3, and 4 in sequence, and iterate multiple times until the positional error of the X-axis and Y-axis of the reference prism imaging crosshairs at the 0-degree position, the 90-degree position, and the -90-degree position is less than 3″.

2. The calibration method according to claim 1, characterized in that, The calibration method further includes: after step five, setting the optical load on the optical load high orthogonality calibration adjustment stage, and then performing steps one to five again.

3. The calibration method according to claim 1, characterized in that, The orthogonal lead screw assembly includes: A first joint bearing is disposed on the mounting base plate; A first lead screw seat is disposed on the first joint bearing, and the first lead screw seat is provided with a positive thread hole, through which the positive thread segment passes; And / or, the reverse thread screw assembly includes: A second joint bearing is provided on the mounting top plate; The second lead screw seat is located on the second joint bearing and has a reverse thread hole, through which the reverse thread section passes.

4. The calibration method according to claim 1, characterized in that, The adjusting shaft assembly also includes an adjusting knob, which is fixed to one end of the positive and negative threaded rod.

5. The calibration method according to claim 1, characterized in that, The fixed shaft assembly includes: A fixed bearing is provided on the mounting base plate; A self-aligning shaft, one end of which is connected to the fixed bearing; The third joint bearing is located on the mounting top plate, and the end of the self-aligning shaft away from the fixed bearing is connected to the third joint bearing.

6. The calibration method according to any one of claims 1 to 5, characterized in that, The optical load high orthogonality calibration adjustment stage also includes a pre-tightening member, one end of which is connected to the mounting base plate and the other end of which is connected to the mounting top plate. The pre-tightening member creates a tensile pre-tightening force between the mounting base plate and the mounting top plate.

7. The calibration method according to any one of claims 1 to 5, characterized in that, The fixed shaft assembly and the two adjusting shaft assemblies are distributed at 120° on the mounting base plate.

8. The calibration method according to any one of claims 1 to 5, characterized in that, The optical load high orthogonality calibration adjustment stage also includes a mounting transition plate, which is located on the side of the mounting top plate away from the mounting bottom plate.

9. The calibration method according to claim 8, characterized in that, The optical load high orthogonality calibration and adjustment stage also includes a tooling plate, which is located on the side of the mounting transition plate opposite to the mounting top plate, and is used to mount the load.

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