Ultra-high vacuum compatible high-precision nanoradian turntable and nanoradian angle output method

Abstract

The application discloses an ultrahigh-vacuum-compatible high-precision nanoradian rotary table and a nanoradian angle output method, and belongs to the technical field of precise adjustment equipment. The rotary table is composed of a rotary seat assembly, a driving assembly, a displacement transmission assembly and an angle output rotary hinge. The driving assembly and the displacement transmission assembly are cores. The nanometer displacement of a piezoelectric actuator is scaled and amplified by a displacement driving hinge, driving force is accurately transmitted through the displacement transmission assembly, and linear displacement is converted into nanoradian rotation through the angle output rotary hinge. The titanium alloy material of the rotary table is suitable for an ultrahigh-vacuum environment, and the piezoelectric actuator is combined to realize overall power-off self-locking. Under a 5kg load, a minimum rotation step of 10nrad and a rotation stroke of 200μrad can be realized, and the problems of poor load, no self-locking, unsuitable vacuum and low rotation precision of existing rotary tables are solved. The structure has high rigidity and stability, and closed-loop control can also be realized.

Description

Technical Field

[0001] This invention relates to the field of precision adjustment equipment technology, specifically to a high-precision nanoradian turntable compatible with ultra-high vacuum and a nanoradian angle output method. Background Technology

[0002] With the rapid development of high-end precision manufacturing and scientific research fields such as semiconductor lithography, synchrotron radiation optical element adjustment, and high-precision scanning stages, extremely high requirements have been placed on the accuracy, load capacity, environmental adaptability and stability of angle adjustment equipment. There is an urgent need for high-precision turntables that can achieve a minimum rotation angle in nanoradians under ultra-high vacuum environments.

[0003] Currently, most high-precision turntables employ piezoelectric stick-slip drive. While these turntables offer a large adjustment stroke, they suffer from significant technical drawbacks: First, their load capacity is poor, failing to meet the precision angle adjustment requirements under heavy load conditions. Second, they lack effective power-off self-locking capability, making them susceptible to external interference after power failure, leading to angle deviation and insufficient stability. Third, their overall structural design and material selection are not adapted to ultra-high vacuum environments, hindering stable operation under such conditions. Fourth, their angular accuracy is limited to the nanoradian level, failing to meet the ultra-precision adjustment requirements of high-end applications. In summary, existing high-precision turntables cannot simultaneously meet the comprehensive technical requirements of ultra-high vacuum environment compatibility, nanoradian angle generation, heavy load bearing, high structural stability, and power-off self-locking, becoming a key issue restricting the technological development of related fields. Summary of the Invention

[0004] The purpose of this invention is to provide a high-precision nanoradian turntable and a nanoradian angle output method that are compatible with ultra-high vacuum, so as to solve the above-mentioned defects.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] This invention proposes a high-precision nanoarc-degree turntable compatible with ultra-high vacuum, characterized in that it comprises: a transition base assembly, a drive assembly, a displacement transmission assembly, and an angle output transition hinge; the transition base assembly is the overall load-bearing foundation of the turntable; the drive assembly and the displacement transmission assembly constitute the core drive and displacement transmission components and are used to generate and transmit sub-nanometer linear displacement; the angle output transition hinge is connected to the displacement transmission assembly and an external load respectively and is used to convert the linear displacement into a nanoarc-degree-of-magnitude rotation angle.

[0007] The drive assembly includes a displacement drive hinge, a pair of powerful magnets, and a piezoelectric actuator. The displacement drive hinge is installed within the adapter assembly. The piezoelectric actuator is connected to the displacement drive hinge, providing nanometer-level displacement input to the turntable and possessing a power-off self-locking function. The pair of powerful magnets is located at the connection point between the piezoelectric actuator and the displacement drive hinge, used to apply preload to ensure tight contact between the two. The displacement drive hinge is an integrated thin-film structure with an integrated displacement scaling hinge structure, used to proportionally scale the input displacement of the piezoelectric actuator and output sub-nanometer linear displacement, while simultaneously amplifying the driving force by a factor of two.

[0008] The displacement transmission component includes a linear displacement transmission hinge and a sinusoidal drive hinge. The linear displacement transmission hinge is fixedly connected to the displacement drive hinge and the sinusoidal drive hinge, and is used to transmit sub-nanometer linear displacement without loss and enhance the straightness and lateral stiffness of the displacement output. The sinusoidal drive hinge is a three-segment decoupled structure and is fixedly connected to the angle output transition hinge, and is used to transmit driving force only in the Tx direction.

[0009] The high-precision nanoarc rotary table, consisting of an adapter assembly, a drive assembly, a displacement transmission assembly, and an angle output adapter hinge, is suitable for ultra-high vacuum environments. Under a 5kg load, it can achieve a minimum rotation step of 10nrad and a rotation stroke of 200μrad. Furthermore, the amplified driving force of the displacement drive hinge, combined with the power-off self-locking characteristic of the piezoelectric actuator, enables the overall mechanism to achieve power-off self-locking.

[0010] Preferably, the displacement driving hinge includes an overall frame, an input end one, a displacement guiding hinge one, an input end two, an intermediate displacement output block, and a displacement guiding hinge two; the intermediate displacement output block is disposed inside the overall frame, and the displacement guiding hinge one and displacement guiding hinge two are respectively disposed at both ends of the intermediate displacement output block and connected to the overall frame to ensure the straightness of the intermediate displacement output block's movement along the x-direction; the input end one and input end two are symmetrically disposed on both sides of the intermediate displacement output block within the overall frame and connected to the output end of the piezoelectric actuator to receive the y-direction displacement input by the piezoelectric actuator; the displacement scaling hinge structure is disposed inside the overall frame and connected to the piezoelectric actuator. Input terminals one and two are connected, with sheet-like hinges at both ends having a preset eccentricity. The displacement scaling factor is determined by the size of the eccentricity, used to convert the input displacement in the y-direction into the x-direction and perform proportional scaling. The intermediate displacement output block is connected to the displacement scaling hinge structure and is used to output the scaled sub-nanometer linear displacement in the x-direction. The intermediate displacement output block has a screw through hole for detachable connection between the displacement driving hinge and the linear displacement transmission hinge. The displacement driving hinge can scale the 25nm step displacement input by the piezoelectric actuator in the y-direction by a factor of 40, and then output a 0.625nm sub-nanometer linear displacement in the x-direction to the intermediate displacement output block.

[0011] Preferably, the linear displacement transmission hinge includes an outer frame, a mounting surface, a sheet-like flexible hinge, a moving end, a first threaded hole, a first pin hole, and a second threaded hole. The outer frame is the basic load-bearing structure of the linear displacement transmission hinge. The first pin hole and the second threaded hole are both located on the outer frame. The second threaded hole corresponds to a threaded locking hole on the outer mounting surface of the overall frame, and the outer frame and the overall frame are detachably fixed together via threaded components. The first pin hole corresponds to a pin positioning hole on the outer mounting surface of the overall frame, and the outer frame and the overall frame are precisely positioned together via pins. The moving end is connected to the outer frame via the sheet-like flexible hinge and is the linear displacement transmission execution structure. The first threaded hole is located on the moving end and is used to detachably fix the moving end to the intermediate displacement output block of the displacement driving hinge. The mounting surface is located on the upper end of the moving end and is used to install and fix the sinusoidal driving hinge. The sheet-like flexible hinge is an elastic connection structure used to transfer motion from the plane of the displacement driving hinge to the upper moving end of the linear displacement transmission hinge.

[0012] Preferably, the sinusoidal drive hinge includes a fixed end, hinge structure one, hinge structure two, and a drive end; the fixed end is detachably fixed to the mounting surface of the linear displacement transmission hinge, serving as the fixed foundation of the sinusoidal drive hinge; the drive end is connected to the inner ring of the angle output transition hinge, serving as the output structure of the driving force; hinge structure one and hinge structure two are connected and perpendicular to each other, with their ends connected to the fixed end and drive end respectively, used to decouple the five degrees of freedom Rx, Ry, Rz, Ty, and Tz, retaining only the Tx degree of freedom required for driving, ensuring that the driving force is transmitted unidirectionally to the angle output transition hinge along the Tx direction.

[0013] Preferably, the angle output adapter hinge includes an outer frame and an inner ring; the outer frame is disposed on the fixed end of the displacement transmission component, and the upper end face of the outer frame has a threaded through hole one and a pin hole two, which are used for positioning the outer frame and the fixed end and for detachable assembly, respectively; the side end face of the outer frame has a threaded hole three, which is used to realize the detachable fixed connection between the angle output adapter hinge and the adapter assembly; a central hole is provided in the center of the outer frame, and the inner ring is disposed in the central hole of the outer frame and connected to the inner wall of the central hole of the outer frame through a wheel-type rotating hinge structure. The first part is the angle output execution structure of the turntable, used to connect with an external load and rotate around the z-axis; the inner ring has a threaded through hole two, used to lock and fix the driving end of the sinusoidal drive hinge to the inner ring; the upper end face of the inner ring has a threaded hole four and a pin hole three, used for precise positioning of the external load and detachable locking, respectively; the angle output adapter hinge is a radial plate hinge structure, used to improve the lateral stiffness and load-bearing capacity of the table; the wheel-type rotating hinge structure is designed with several centrally symmetrical annular spokes to reduce the drift of the rotation center during rotation.

[0014] Preferably, the drive assembly further includes a top seat, a tungsten carbide gasket, and a piezoelectric actuator mounting base. The top seat is positioned between the piezoelectric actuator and the input ends of the displacement drive hinge, forming the basic structure for applying preload. The tungsten carbide gasket is fitted onto the end face of the top seat facing the piezoelectric actuator, contacting the output end of the piezoelectric actuator to reduce contact wear. A pair of strong magnets with opposite poles are positioned at corresponding positions on the top seat and the displacement drive hinge. The magnets apply preload through the principle of opposite pole attraction, and the attraction force is inversely proportional to the distance, working in conjunction with the hinge's restoring force to maintain a constant preload within a certain range, further ensuring tight contact between the piezoelectric actuator and the tungsten carbide gasket. The piezoelectric actuator mounting base is mounted on the adapter assembly to fix the fixed end of the piezoelectric actuator, ensuring the installation stability of the piezoelectric actuator.

[0015] Preferably, the adapter assembly includes an adapter and a capacitive sensor. The adapter is the main supporting structure of the adapter assembly, and its side has two screw through holes for locking the angle output adapter hinge onto the adapter. The capacitive sensor is detachably installed in a semi-circular groove at the bottom of the adapter via a capacitive sensor pressure block. The drive assembly also includes a capacitive sensor plate, which is connected to the intermediate displacement output block of the displacement drive hinge and forms a detection structure with the capacitive sensor. This structure is used to detect the linear displacement of the intermediate displacement output block in the x-direction in real time, and the linear displacement corresponds one-to-one with the rotation angle of the turntable. After calibration, the rotation angle of the turntable can be calculated from the detected displacement. The displacement drive hinge, linear displacement transmission hinge, sine drive hinge, and angle output adapter hinge are all integrally machined using slow wire EDM to ensure the machining accuracy and integrated performance of each hinge structure.

[0016] Preferably, the capacitive sensor is an ultra-high vacuum version sensor, which is adapted to the ultra-high vacuum environment with the titanium alloy structure. The displacement data detected by the sensor can be transmitted to an external control terminal for real-time monitoring and control of the turntable angle.

[0017] Preferably, a nanoradian angle output method, based on the aforementioned ultra-high vacuum compatible high-precision nanoradian turntable, includes the following steps:

[0018] S1. Place the strong magnets with opposite poles facing each other at the corresponding positions of the top seat and the displacement drive hinge. Apply preload through the principle of opposite poles attracting each other, so that the preload and the hinge restoring force are kept constant, ensuring that the output end of the piezoelectric actuator is in close contact with the tungsten carbide gasket on the top seat.

[0019] S2. The piezoelectric actuator is controlled by an external control terminal to input a displacement of 25nm step size to input end one and input end two of the displacement driving hinge in the y direction. The displacement driving hinge scales the input displacement by 40 times in the x direction through the internal displacement scaling hinge structure with eccentricity. The intermediate displacement output block outputs a sub-nanometer linear displacement of 0.625nm. At the same time, the displacement driving hinge amplifies the driving force by the same multiple.

[0020] S3. The linear displacement transmission hinge receives the sub-nanometer linear displacement output by the intermediate displacement output block through the moving end. After being guided by the sheet-like flexible hinge, the displacement is transmitted without loss and moves linearly along the x-axis, while enhancing the lateral stiffness and straightness of the displacement output.

[0021] S4. The sinusoidal drive hinge receives linear displacement through the fixed end and transmits the motion driving force of the hinge. The driving force is decoupled in five degrees of freedom (Rx, Ry, Rz, Ty, Tz) through the mutually perpendicular hinge structure one and hinge structure two. Only the driving force in the Tx direction is transmitted to the inner ring of the angle output adapter hinge through the drive end.

[0022] S5. Under the driving force in the Tx direction, the inner ring of the angle output adapter hinge rotates around the z-axis through the wheel-type rotating hinge structure, converting the sub-nanometer linear displacement into a 10 nrad nano-arc-level rotation angle, thus completing the nano-arc-degree angle output and realizing precise angle adjustment of external loads.

[0023] S6. When the high-precision nanoarc turntable compatible with ultra-high vacuum is powered off, the amplified driving force of the displacement drive hinge is used in conjunction with the power-off self-locking characteristic of the piezoelectric actuator to keep the overall mechanism of the turntable at a fixed rotation angle, thereby achieving power-off self-locking, ensuring angle stability and preventing external interference.

[0024] S7. A sine plate with two plane mirrors is mounted on the turntable's angle output hinge. A laser interferometer is used to measure the real-time displacement of the two plane mirrors during the turntable's rotation. The arcsine conversion is performed using the displacement difference between the two plane mirrors and the straight-line distance between them to complete the test and calibration of the turntable's angle output accuracy.

[0025] Preferably, after calibration in step S7, the linear displacement in the x-direction of the displacement drive hinge intermediate displacement output block is detected in real time by the cooperation of the capacitive sensor installed on the adapter with the capacitive sensor plate. Based on the one-to-one correspondence between linear displacement and rotation angle, the detected displacement data is converted into the real-time rotation angle of the turntable. The external control terminal adjusts the step size and direction of the y-direction input displacement of the piezoelectric actuator in real time according to the deviation between the actual value and the target value of the rotation angle, thereby realizing closed-loop control of the turntable rotation angle.

[0026] The beneficial effects of this invention are as follows:

[0027] This invention discloses a high-precision nanoradian turntable compatible with ultra-high vacuum. Through a modular and collaborative design of the adapter assembly, drive assembly, displacement transmission assembly, and angle output hinge, it specifically addresses the core technical problems of existing high-precision turntables, such as poor load capacity, lack of power-off self-locking function, inability to adapt to ultra-high vacuum environments, and inability to achieve nanoradian-level angular accuracy. The structural and functional design of each core component forms an organic whole, achieving comprehensive technical effects including ultra-high vacuum compatibility, nanoradian-level angle generation, stable large load bearing, and reliable power-off self-locking. It also possesses a large stroke angle adjustment capability. Specific beneficial effects are as follows:

[0028] (1) This invention can achieve adaptation to ultra-high vacuum environment and meet the special working conditions of high-end fields. Through the adaptability design of the overall structure and materials, the turntable can be stably applied to ultra-high vacuum environment, breaking through the technical limitation that the existing turntable cannot achieve precise angle adjustment under ultra-high vacuum conditions, and can meet the vacuum working conditions requirements of high-end scientific research and manufacturing fields such as synchrotron radiation technology and semiconductor lithography.

[0029] (2) This invention can achieve ultra-high angular accuracy at the nanoradian level and realize ultra-precise angle generation. The displacement driving hinge in the drive component is an integrated thin-film structure and integrates a displacement scaling hinge structure, which can proportionally scale the nano-level displacement input by the piezoelectric actuator and output sub-nanometer linear displacement. After the linear displacement angle is transmitted by the displacement transmission component and converted by the angle output transition hinge, nanoradian level angular output is realized; and the turntable can stably achieve a minimum angular step of 10 nrad under a 5kg load. The angular accuracy is far superior to the existing piezoelectric stick-slip drive turntable, meeting the core requirements of ultra-precise angle adjustment.

[0030] (3) This invention enables stable operation under heavy loads, enhancing the practical application value of the turntable. The core drive and displacement transmission components, consisting of the drive assembly and the displacement transmission assembly, utilize the amplified driving force design of the displacement drive hinge and the stiffness enhancement of the linear displacement transmission hinge, combined with the structural characteristics of the angle output transition hinge, to enable the turntable to operate stably under a 5kg load. This solves the problem of poor load capacity of existing turntables, significantly improving the application scenarios and value of the turntable in practical engineering, and making it suitable for ultra-precision adjustment conditions with high load requirements.

[0031] (4) The present invention has a reliable power-off self-locking function, ensuring the stability of the angle after power failure. The present invention combines the power-off self-locking characteristic of the piezoelectric actuator with the driving force amplification function of the displacement driving hinge. The displacement driving hinge amplifies the driving force by an equal multiple while scaling the input displacement. The combination of the two enables the turntable to maintain a fixed rotation angle after power failure, and it is not easy to be affected by external forces and cause angle deviation. This solves the technical defect of insufficient stability of the existing turntable after power failure and ensures long-term accuracy after angle adjustment.

[0032] (5) This invention can achieve large stroke angle adjustment, taking into account both adjustment accuracy and adjustment range. The turntable of this invention achieves a minimum angle step of 10 nrad nanoradians while the angle stroke can reach 200 μrad, taking into account both ultra-precise angle adjustment accuracy and a wide angle adjustment range. It solves the problem that existing high-precision turntables mostly sacrifice stroke for accuracy or sacrifice accuracy for stroke, and can meet the angle adjustment needs in different scenarios, thus improving the versatility of the turntable.

[0033] (6) This invention ensures the accuracy and stability of angle output through gapless displacement transmission. The displacement drive hinge in the drive component of this invention is an integrated thin-film structure. The linear displacement transmission hinge of the displacement transmission component is fixedly connected to the sinusoidal drive hinge to form a seamless transmission link. The angle output transition hinge is fixedly connected to the displacement transmission component to realize the direct conversion of linear displacement to angle. The entire transmission process has no assembly gap and no displacement transmission loss, ensuring the accuracy of the conversion of sub-nanometer linear displacement to nano-radian angle, so that the angle output of the turntable has high stability and consistency.

[0034] (7) The present invention improves the ease of assembly and maintenance of the turntable through modular structural design. The turntable of the present invention is divided into four major modules: adapter assembly, drive assembly, displacement transmission assembly, and angle output adapter hinge. The drive assembly and displacement transmission assembly constitute an integrated core drive and displacement transmission assembly. The modules are fixedly connected to achieve precise assembly. The modular structural design makes the assembly accuracy of the turntable easy to control, and at the same time facilitates subsequent maintenance, disassembly and precision calibration, reducing the difficulty of operation in actual use. Attached Figure Description

[0035] Appendix Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0036] Appendix Figure 2 This is a schematic diagram of the structure of the drive component and displacement transmission component of the present invention;

[0037] Appendix Figure 3 This is a schematic diagram of the displacement-driven hinge of the present invention;

[0038] Appendix Figure 4 This is a schematic diagram of the linear displacement transmission hinge of the present invention;

[0039] Appendix Figure 5 This is a schematic diagram of the sinusoidal drive hinge of the present invention;

[0040] Appendix Figure 6 This is a schematic diagram of the angle output adapter hinge of the present invention;

[0041] Appendix Figure 7This is a schematic diagram of the adapter assembly of the present invention;

[0042] Appendix Figure 8 This is a schematic diagram showing the interaction between the capacitive sensor and the capacitive sensor plate of the present invention;

[0043] Appendix Figure 9 This is a front view of the prototype of the high-precision nano-arc turntable of the present invention;

[0044] Appendix Figure 10 This is a photograph of the bottom surface of the prototype of the high-precision nano-arc turntable of the present invention;

[0045] Appendix Figure 11 This is a test photo of the 1-step rotation angle output of the high-precision nano-arc turntable prototype of the present invention;

[0046] Appendix Figure 12 This is a diagram showing the displacement results of two plane mirrors in the 1-step rotation angle output test of the high-precision nanoradian turntable prototype of this invention;

[0047] Appendix Figure 13 The image shows the actual rotation angle results of the 1-step rotation angle output test of the high-precision nanoarc turntable prototype of this invention.

[0048] In the diagram, 1. Adapter assembly, 2. Drive assembly, 3. Displacement transmission assembly, 4. Angle output adapter hinge, 101. Adapter, 101-1. Adapter positioning pin hole, 101-2. Adapter threaded hole, 101-3. Screw through hole two, 102. Capacitive sensor pressure block, 103. Capacitive sensor, 201. Displacement drive hinge, 201-1. Overall frame, 201-2. Input end one, 201-5. Displacement guide hinge one, 201-6. Displacement scaling hinge structure, 201-7. Input end two, 201-8. Intermediate displacement output block, 201-9. Displacement guide hinge two, 201-10. Screw through hole one, 202. Top seat, 203. Tungsten carbide gasket, 204. Strong magnet pair, 205. Piezoelectric actuator, 206. Piezoelectric actuator mounting. 207. Fixed seat; 301. Capacitive sensor plate; 301. Linear displacement transmission hinge; 301-1. Outer frame; 301-2. Mounting surface; 301-3. Sheet-shaped flexible hinge; 301-4. Moving end; 301-5. Threaded hole one; 301-6. Pin hole one; 301-7. Threaded hole two; 302. Sine drive hinge; 302-1. Fixed end mounting hole; 302-2. Fixed end; 302-3. Hinge structure one; 302-4. Hinge structure two; 302-5. Drive end; 302-6. Drive end mounting hole; 4-1. Outer frame; 4-2. Threaded through hole one; 4-3. Pin hole two; 4-4. Wheel-type rotating hinge structure; 4-5. Threaded hole three; 4-6. Inner ring; 4-7. Threaded through hole two; 4-8. Threaded hole four; 4-9. Pin hole three. Detailed Implementation

[0049] The present invention will be further described below with reference to the embodiments. It should be noted that these are merely examples and descriptions of the inventive concept. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the inventive concept or exceed the scope defined in the claims, they should all be considered to fall within the protection scope of the present invention.

[0050] Example 1:

[0051] Combined with appendix Figures 1-13 The following describes a high-precision nano-arc turntable compatible with ultra-high vacuum according to the present invention:

[0052] like Figure 1 As shown, this invention proposes a high-precision nanoarc-degree turntable compatible with ultra-high vacuum, comprising an adapter assembly 1, a drive assembly 2, a displacement transmission assembly 3, and an angle output hinge 4. The adapter assembly 1 serves as the overall load-bearing foundation of the turntable; the drive assembly 2 and the displacement transmission assembly 3 are assembled into an integrated core drive and displacement transmission component (as shown in the attached diagram). Figure 2 As shown, the entire assembly is mounted on the adapter 101 of the adapter assembly 1, and is used to generate and transmit sub-nanometer linear displacement; the angle output adapter hinge 4 is connected to the displacement transmission assembly 3 and the external load respectively and is used to convert the linear displacement into a nano-arc-level rotation angle.

[0053] The drive assembly 2 includes a displacement drive hinge 201, a pair of powerful magnets 204, and a piezoelectric actuator 205. The displacement drive hinge 201 is installed inside the adapter assembly 1. The piezoelectric actuator 205 is connected to the displacement drive hinge 201, providing nanometer-level displacement input to the turntable, and has a power-off self-locking function. The pair of powerful magnets 204 is located at the connection between the piezoelectric actuator 205 and the displacement drive hinge 201, and is used to apply a preload to ensure tight contact between the two. The displacement drive hinge 201 is an integrated thin-film structure and integrates a displacement scaling hinge structure 201-6, which is used to proportionally scale the input displacement of the piezoelectric actuator 205 and output sub-nanometer linear displacement, while amplifying the driving force by an equal multiple.

[0054] The displacement transmission component 3 includes a linear displacement transmission hinge 301 and a sinusoidal drive hinge 302. The linear displacement transmission hinge 301 is fixedly connected to the displacement drive hinge 201 and the sinusoidal drive hinge 302, and is used to transmit sub-nanometer linear displacement without loss and enhance the straightness and lateral stiffness of the displacement output. The sinusoidal drive hinge 302 is a three-segment decoupled structure and is fixedly connected to the angle output transition hinge 4, and is used to transmit the driving force only in the Tx direction.

[0055] The high-precision nanoarc rotary table, consisting of adapter assembly 1, drive assembly 2, displacement transmission assembly 3 and angle output adapter hinge 4, is suitable for ultra-high vacuum environments. Under a 5kg load, it can achieve a minimum rotation step of 10nrad and a rotation stroke of 200μrad. Furthermore, the amplified driving force of the displacement drive hinge 201, combined with the power-off self-locking characteristic of the piezoelectric actuator 205, enables the overall mechanism to achieve power-off self-locking.

[0056] This invention provides a high-precision nanoradian turntable compatible with ultra-high vacuum, which solves the technical problems of existing high-precision turntables such as poor load capacity, lack of power-off self-locking function, inability to adapt to ultra-high vacuum environment, and inability to achieve nanoradian-level rotation accuracy. At the same time, it realizes high stability and large stroke angle adjustment of the turntable under large load, meeting the ultra-precision adjustment requirements of fields such as synchrotron radiation and semiconductor lithography.

[0057] Example 2:

[0058] Combined with appendix Figures 1-13 The following describes a high-precision nano-arc turntable compatible with ultra-high vacuum according to the present invention:

[0059] like Figure 1 As shown, this invention proposes a high-precision nanoarc-degree turntable compatible with ultra-high vacuum, comprising an adapter assembly 1, a drive assembly 2, a displacement transmission assembly 3, and an angle output hinge 4. The adapter assembly 1 serves as the overall load-bearing foundation of the turntable; the drive assembly 2 and the displacement transmission assembly 3 are assembled into an integrated core drive and displacement transmission component (as shown in the attached diagram). Figure 2 As shown, the entire assembly is mounted on the adapter 101 of the adapter assembly 1, and is used to generate and transmit sub-nanometer linear displacement; the angle output adapter hinge 4 is connected to the displacement transmission assembly 3 and the external load respectively and is used to convert the linear displacement into a nano-arc-level rotation angle.

[0060] The specific structure and connection relationship of the adapter assembly 1, drive assembly 2, displacement transmission assembly 3, and angle output adapter hinge 4 are as follows:

[0061] (a) Driver components.

[0062] Drive component 2 is the core of the rotary table's displacement input, as shown in the attached diagram. Figure 2 As shown, the system includes a displacement drive hinge 201, a top seat 202, a tungsten carbide gasket 203, a pair of powerful magnets 204, a piezoelectric actuator 205, a piezoelectric actuator mounting base 206, and a capacitive sensor electrode plate 207. The positions, connections, and functions of each component are as follows:

[0063] 1. Displacement drive hinge 201: This is the core displacement scaling component of drive assembly 2, and it is machined into an integrated thin-film structure using slow wire EDM (as shown in the attached image). Figure 3As shown, the components include an overall frame 201-1, input end 1 201-2, displacement guide hinge 1 201-5, displacement scaling hinge structure 201-6, input end 2 201-7, intermediate displacement output block 201-8, displacement guide hinge 2 201-9, and screw through hole 1 201-10. All sub-components are integrally molded without assembly gaps. Their specific structure and functions are as follows:

[0064] Overall frame 201-1: It is the basic load-bearing structure for the outer contour of the displacement drive hinge 201. All sub-components are integrated inside the overall frame 201-1. Its exterior is fixedly connected to the outer frame 301-1 of the linear displacement transmission hinge 301, providing an overall installation foundation for the displacement drive hinge 201, while ensuring the structural rigidity of the hinge.

[0065] Input terminal 1 201-2 and input terminal 2 201-7 are symmetrically arranged inside the overall frame 201-1 on the same side of the intermediate displacement output block 201-8, and directly contact the top seat 202. They are used to receive the nanometer-level displacement in the y-direction transmitted by the piezoelectric actuator 205 through the top seat 202, and transmit the displacement to the displacement scaling hinge structure 201-6 without loss.

[0066] The displacement scaling hinge structure 201-6 is located inside the overall frame 201-1. Its two ends are integrated with input end 201-2, input end 201-7, and the intermediate displacement output block 201-8, respectively. Both ends are equipped with sheet-like hinges with a preset eccentricity. The displacement scaling factor is determined by the size of the eccentricity. In this embodiment, the eccentricity of the displacement scaling hinge structure 201-6 is designed to have a scaling ratio of 40. This allows the 25nm displacement input from the piezoelectric actuator 205 to be converted into an x-direction displacement and scaled by 40 times, outputting a sub-nanometer linear displacement of 0.625nm to the intermediate displacement output block 201-8. Simultaneously, the displacement scaling hinge structure 201-6 amplifies the driving force by the same factor while scaling the displacement, providing a driving force basis for the turntable's large load bearing and power-off self-locking.

[0067] Intermediate displacement output block 201-8: Located in the central area inside the overall frame 201-1, it is the core component for displacement output of displacement drive hinge 201. It is integrated with displacement scaling hinge structure 201-6 and is used to receive the scaled sub-nanometer linear displacement in the x-direction. The displacement is then transmitted to linear displacement transmission hinge 301 through screw through hole 201-10. The screw through hole 201-10 on intermediate displacement output block 201-8 is a reference hole for connecting with the moving end 301-4 of linear displacement transmission hinge 301, enabling detachable connection between the two.

[0068] Displacement guide hinge 1 201-5 and displacement guide hinge 2 201-9 are symmetrically arranged at the left and right ends of the intermediate displacement output block 201-8. The two ends are integrated with the intermediate displacement output block 201-8 and the overall frame 201-1, respectively, providing precise linear guidance for the x-direction movement of the intermediate displacement output block 201-8. Both hinges are sheet-like flexible hinges, which can only produce slight elastic deformation in the x-direction. They have extremely strong constraint stiffness for displacement in the y and z-axis directions and rotation in the Rx, Ry, and Rz directions. They can limit the parasitic movement of the intermediate displacement output block 201-8 and ensure that it only makes linear displacement in the x-direction, avoiding the loss of transmission accuracy caused by displacement deviation.

[0069] 2. Piezoelectric actuator mounting base 206: Installed in the preset mounting area of ​​the adapter 101 of the adapter assembly 1, and detachably fixed to the adapter 101 by means of threaded parts. Its core function is to fix the fixed end of the piezoelectric actuator 205, restrict the circumferential and radial displacement of the piezoelectric actuator 205, ensure that the piezoelectric actuator 205 can move without jamming in the y-direction, and provide a rigid mounting base for the stable operation of the piezoelectric actuator 205.

[0070] 3. Piezoelectric actuator 205: The fixed end is locked in the preset assembly slot of the piezoelectric actuator mounting base 206, and the output end is set towards the displacement drive hinge 201 to provide nanometer-level displacement input in the y direction for the turntable. It has a power-off self-locking characteristic and can maintain its extension and retraction state after power failure, providing a basis for the overall power-off self-locking of the turntable. The minimum output step size of the piezoelectric actuator 205 is 25nm, which is the basis for realizing nano-arc-level rotation displacement input.

[0071] 4. Top seat 202 and tungsten carbide gasket 203: The top seat 202 is positioned between the output end of the piezoelectric actuator 205 and the input ends 201-2 and 201-7 of the displacement drive hinge 201, serving as the basic transition structure for applying preload. The tungsten carbide gasket 203 is fixedly attached to the end face of the top seat 202 facing the piezoelectric actuator 205, directly contacting the output end of the piezoelectric actuator 205. Utilizing the high hardness of tungsten carbide, it reduces contact wear at the output end of the piezoelectric actuator 205 during displacement transmission, ensuring long-term accuracy of displacement transmission.

[0072] 5. Strong magnet pair 204: Opposite poles are positioned opposite each other at the corresponding positions of the top seat 202 and the displacement drive hinge 201. Preload is applied to the connection between the piezoelectric actuator 205 and the displacement drive hinge 201 by the principle of attraction between opposite poles. Since the attraction force of the magnet is inversely proportional to the distance, while the hinge restoring force of the displacement drive hinge 201 is directly proportional to the distance, the two work together to maintain a constant preload within a certain range, thereby ensuring close contact between the piezoelectric actuator 205, the tungsten carbide gasket 203, the top seat 202 and the displacement drive hinge 201, and avoiding displacement transmission loss due to gaps.

[0073] 6. Capacitive sensor plate 207: It is fixedly connected to the intermediate displacement output block 201-8 of the displacement drive hinge 201 by a threaded part. It moves linearly in the x direction synchronously with the intermediate displacement output block 201-8. Its core function is to cooperate with the capacitive sensor 103 of the adapter assembly 1 to form a displacement detection structure and provide real-time feedback on the linear displacement of the intermediate displacement output block 201-8 in the x direction.

[0074] (ii) Displacement transfer components.

[0075] The displacement transmission component 3 is the core of the turntable's precise displacement transmission, including a linear displacement transmission hinge 301 and a sinusoidal drive hinge 302. It achieves lossless transmission of sub-nanometer linear displacement and decoupling of driving force, ensuring that the driving force is unidirectionally transmitted along the Tx direction to the angle output transition hinge 4. Both the linear displacement transmission hinge 301 and the sinusoidal drive hinge 302 are integrally machined using slow wire EDM, seamlessly connecting with the displacement drive hinge 201. The specific structure and connection relationship are as follows:

[0076] Linear displacement transmission hinge 301: as attached Figure 4 As shown, the structure includes an outer frame 301-1, a mounting surface 301-2, a sheet-like flexible hinge 301-3, a moving end 301-4, a threaded hole 301-5, a pin hole 301-6, and a threaded hole 301-7. These components serve as the transmission carrier for displacement from the displacement-driven hinge 201 to the sinusoidal-driven hinge 302, while also enhancing the straightness and lateral stiffness of the displacement output. The functions and connections of each component are as follows:

[0077] Outer frame 301-1: This is the basic load-bearing structure for the linear displacement transmission hinge 301. Threaded hole 2 301-7 and pin hole 1 301-6 are provided on it. Threaded hole 2 301-7 corresponds to the threaded locking hole on the outer mounting end face of the overall frame 201-1, and the outer frame 301-1 and the overall frame 201-1 are detachably fixed together through the threaded parts. Pin hole 1 301-6 corresponds to the pin positioning hole on the outer mounting end face of the overall frame 201-1, and the pins are used to achieve precise positioning of the outer frame 301-1 and the overall frame 201-1, ensuring the installation accuracy of both and avoiding displacement transmission errors caused by assembly deviations.

[0078] Mobile end 301-4: It is elastically connected to the outer frame 301-1 through a sheet-like flexible hinge 301-3, which is the structure for transmitting and executing linear displacement; the threaded hole 301-5 on the mobile end 301-4 cooperates with the screw through hole 201-10 of the displacement drive hinge 201, so as to realize the detachable connection between the mobile end 301-4 and the intermediate displacement output block 201-8, thereby receiving the sub-nanometer linear displacement in the x-direction transmitted by the intermediate displacement output block 201-8 and moving linearly along the x-axis.

[0079] The sheet-like flexible hinge 301-3 is an elastic connection structure. Its two ends are integrated with the outer frame 301-1 and the moving end 301-4, respectively. Its core function is to enhance the lateral stiffness and straightness of the displacement output, and at the same time transfer the motion from the plane where the displacement driving hinge 201 is located to the upper moving end 301-4 of the linear displacement transmission hinge 301, so as to realize the spatial transmission of displacement and provide a spatial basis for the assembly and driving force transmission of the sinusoidal driving hinge 302.

[0080] Mounting surface 301-2: Located on the upper surface of the moving end 301-4, it serves as the fixed mounting surface for the sinusoidal drive hinge 302, enabling precise connection between the sinusoidal drive hinge 302 and the linear displacement transmission hinge 301, ensuring that the linear motion of the moving end 301-4 can be transmitted to the sinusoidal drive hinge 302 without loss.

[0081] Sine-driven hinge 302: as attached Figure 5 As shown, this is a three-section decoupling structure, including fixed end 302-2, hinge structure one 302-3, hinge structure two 302-4, and driving end 302-5. All components are integrally molded. Its core function is to decouple the driving force transmitted by the linear displacement transmission hinge 301, retaining only the driving force in the Tx direction and transmitting it to the angle output transition hinge 4. Specific structure and function are as follows:

[0082] Fixed end 302-2: It is provided with a fixed end mounting hole 302-1, which corresponds to the threaded hole provided on the mounting surface 301-2 of the linear displacement transmission hinge 301. It is detachably fixed by using threaded parts and serves as the fixed base for the sinusoidal drive hinge 302. It is used to receive the linear motion driving force transmitted by the moving end 301-4.

[0083] Hinge structure 1 302-3 and hinge structure 2 302-4 are mutually perpendicular elastic hinge structures, with both ends integrated with the fixed end 302-2 and the driving end 302-5 respectively. Through the vertical structure design of the two, the five degrees of freedom Rx, Ry, Rz, Ty, and Tz can be decoupled, retaining only the Tx degree of freedom required for driving, avoiding parasitic forces in other directions from interfering with the transmission of driving force, and ensuring that the driving force is transmitted unidirectionally along the Tx direction to the inner ring 4-6 of the angle output adapter hinge 4.

[0084] Drive end 302-5: This is the driving force output end of the sinusoidal drive hinge 302. It is locked and fixed to the inner ring 4-6 of the angle output adapter hinge 4 through the threaded through hole 4-7. It is used to transmit the driving force in the Tx direction to the inner ring 4-6, push the inner ring 4-6 to rotate around the z axis, and realize the conversion of linear displacement to angle.

[0085] (iii) Angle output adapter hinge.

[0086] Angle output adapter hinge 4 is the core of the turntable's angle output, as shown in the attached figure. Figure 6 As shown, the turntable includes an outer frame 4-1, threaded through hole 1 4-2, pin hole 2 4-3, wheel-type rotating hinge structure 4-4, threaded hole 3 4-5, inner ring 4-6, threaded through hole 2 4-7, threaded hole 4-8, and pin hole 3 4-9. It adopts a radial, plate-like hinge structure design and is integrally machined using slow wire EDM. This achieves the conversion from linear displacement to nanoradian-level rotation, while also improving the turntable's load-bearing capacity and rotational stability. The functions and connections of each component are as follows:

[0087] The outer frame 4-1 serves as the basic load-bearing structure for the angle output adapter hinge 4. The pin hole 4-3 on its upper end face engages with the matching pin hole on the fixed end 302-2 of the sinusoidal drive hinge 302, achieving precise positioning between the outer frame 4-1 and the fixed end 302-2 via the pin. The threaded through hole 4-2 on its upper end face is a threaded component through-hole. The threaded component passes through this hole and engages with the matching threaded hole on the fixed end 302-2, achieving a detachable connection between the outer frame 4-1 and the sinusoidal drive hinge 302. The threaded hole 4-5 on the side end face of the outer frame 4-1 engages with the screw through hole 101-3 on the adapter seat 101 of the adapter seat assembly 1, achieving a detachable connection between the angle output adapter hinge 4 and the adapter seat 101, providing an overall mounting foundation for the angle output adapter hinge 4.

[0088] Wheel-type rotating hinge structure 4-4: Located between the inner wall of the central hole of the outer frame 4-1 and the inner ring 4-6, it consists of several centrally symmetrical annular spokes, serving as an elastic connection structure between the inner ring 4-6 and the outer frame 4-1. Its core function is to enable the inner ring 4-6 to rotate flexibly around the z-axis. At the same time, the centrally symmetrical annular spoke design can reduce the drift of the rotation center during rotation, ensuring the accuracy of the rotation angle. The radial plate-like hinge structure can also improve the lateral stiffness of the table surface, further enhancing the load-bearing capacity of the turntable.

[0089] Inner ring 4-6: Located in the center hole of outer frame 4-1, it is connected to outer frame 4-1 through wheel-type rotating hinge structure 4-4. It serves as the angle output execution structure of the turntable and also as the mounting interface for external loads. The threaded through hole 4-7 on inner ring 4-6 corresponds to the drive end mounting hole 302-6 on drive end 302-5. It is used to lock and fix drive end 302-5 of sinusoidal drive hinge 302 to inner ring 4-6, ensuring that the driving force in the Tx direction of drive end 302-5 can be transmitted to inner ring 4-6 without loss, driving inner ring 4-6 to rotate around z-axis. The threaded hole 4-8 and pin hole 4-9 on the upper end face of inner ring 4-6 are used for precise positioning and detachable locking of external loads, respectively, to achieve precise docking between turntable and external load, ensuring accurate transmission of angle adjustment.

[0090] When the driving end 302-5 of the sinusoidal drive hinge 302 applies a driving force in the Tx direction to the inner ring 4-6, the inner ring 4-6 rotates around the z-axis under the constraint of the wheel-type rotating hinge structure 4-4. Since the linear displacement in the input Tx direction is sub-nanometer (0.625nm), after the linear displacement-angle conversion, the rotation angle generated by the inner ring 4-6 is on the order of nanoarcs. In this embodiment, a minimum rotation step of 10nrad is achieved, the rotation stroke can reach 200μrad, and it can still maintain stable rotation under a 5kg load.

[0091] (iv) Adapter assembly.

[0092] Adapter assembly 1 serves as the overall load-bearing and testing foundation for the turntable, as shown in the attached diagram. Figure 7 As shown, the functions and connections of the disclosed components, including the adapter 101 and the capacitive sensor 103, are as follows:

[0093] Adapter 101: This is the main load-bearing structure of adapter assembly 1, made of titanium alloy, suitable for ultra-high vacuum environments. The screw through hole 101-3 on its side mates with the threaded hole 4-5 of the angle output adapter hinge 4, enabling a detachable connection between the angle output adapter hinge 4 and adapter 101. Adapter 101 has a pre-set mounting position for the capacitive sensor 103, and also provides an overall mounting base for the drive assembly 2 and displacement transmission assembly 3, ensuring the coaxiality of the assembly of each component of the turntable. The structural design of adapter 101 must ensure the overall rigidity of the turntable to avoid affecting the angular accuracy of the turntable due to its own deformation.

[0094] The bottom surface of the adapter 101 is provided with adapter positioning pin holes 101-1 and adapter threaded holes 101-2. The adapter positioning pin holes 101-1 are high-precision through holes, with multiple holes symmetrically / diagonally distributed along the bottom mounting plane of the adapter 101. These holes correspond to the positioning pin holes on the external mounting reference surface, ensuring precise positioning of the entire nano-arc turntable in terms of coaxiality, perpendicularity, and flatness with the external mechanism, eliminating assembly misalignment. The adapter threaded holes 101-2 are blind / through-hole internal thread structures, with multiple holes evenly distributed along the mounting plane. These holes correspond to the threaded mounting holes on the external mounting reference surface, and, with the help of bolts, firmly lock the adapter 101 to the external mounting platform / equipment base, ensuring the overall installation rigidity of the turntable and suppressing vibration and displacement.

[0095] Capacitive sensor 103: Utilizing an ultra-high vacuum version of the capacitive sensor, its titanium alloy structure is adapted for ultra-high vacuum operating environments; see attached... Figure 8 As shown, the capacitive sensor 103 is detachably installed in the pre-set semi-circular groove at the bottom of the adapter 101. In actual use, after adjusting the range distance between the capacitive sensor 103 and the capacitive sensor plate 207, the capacitive sensor 103 is fixed and pressed tightly by the capacitive sensor clamping block 102. The capacitive sensor 103 and the capacitive sensor plate 207 of the drive assembly 2 cooperate to form a displacement detection structure, which is used to detect the linear displacement in the x-direction of the intermediate displacement output block 201-8 of the displacement drive hinge 201 in real time. Since there is a one-to-one linear relationship between the linear displacement in the x-direction of the intermediate displacement output block 201-8 and the rotation angle of the turntable, the displacement data detected by the capacitive sensor 103 can be directly converted into the real-time rotation angle of the turntable after calibration. The displacement data detected by the capacitive sensor 103 can be transmitted to an external control terminal to provide a data basis for real-time monitoring and closed-loop control of the turntable angle.

[0096] As attached Figure 9 Appendix Figure 10 The image shown is a prototype of the nano-arc turntable of this invention. Figure 9 A frontal view clearly shows the outer frame 4-1, inner ring 4-6, and external load mounting interface of the angle output adapter hinge 4; (Attached) Figure 10 The bottom view clearly shows the structure of the adapter 101 and the reserved installation position of the capacitive sensor 103. The overall structure of the prototype is completely consistent with the above technical solution, verifying the feasibility of the technical solution.

[0097] Example 3:

[0098] The present invention provides a nanoradian angle output method, which is based on the ultra-high vacuum compatible high-precision nanoradian turntable disclosed in Example 2, and specifically includes the following steps:

[0099] S1. Preload application: The opposite poles of the strong magnets 204 are set at the corresponding positions of the top seat 202 and the displacement drive hinge 201. The preload is applied by means of the attraction between opposite poles. By utilizing the combination of the attraction between the magnets and the restoring force of the hinge, the preload is kept constant within a certain range. This ensures that the output end of the piezoelectric actuator 205 is in close contact with the tungsten carbide gasket 203 on the top seat 202, thus avoiding gaps in displacement transmission.

[0100] S2, Nanoscale Displacement Input and Scaling: A control signal is sent to the piezoelectric actuator 205 via an external control terminal to control the piezoelectric actuator 205 to input a displacement of 25nm steps in the y-direction to the input terminals 201-2 and 201-7 of the displacement driving hinge 201; the displacement driving hinge 201 converts the y-direction input displacement into the x-direction displacement and scales it by 40 times through the internal displacement scaling hinge structure 201-6 with eccentricity, and outputs a sub-nanometer linear displacement of 0.625nm by the intermediate displacement output block 201-8. At the same time, the displacement driving hinge 201 amplifies the driving force by 40 times.

[0101] S3, Sub-nanometer linear displacement transmission: The moving end 301-4 of the linear displacement transmission hinge 301 receives the sub-nanometer linear displacement output by the intermediate displacement output block 201-8 through the threaded hole 301-5. After being guided and stiffened by the sheet-like flexible hinge 301-3, the displacement is transmitted without loss and moves linearly along the x-axis. At the same time, the sheet-like flexible hinge 301-3 transfers the motion from the plane where the displacement driving hinge 201 is located to the upper moving end 301-4.

[0102] S4. Decoupling of driving force: The fixed end 302-2 of the sinusoidal drive hinge 302 receives the motion driving force transmitted by the moving end 301-4 of the linear displacement transmission hinge 301. The driving force is decoupled in five degrees of freedom (Rx, Ry, Rz, Ty, Tz) by the mutually perpendicular hinge structure 1 302-3 and hinge structure 2 302-4, retaining only the driving force in the Tx direction. The driving force is then transmitted to the inner ring 4-6 of the angle output adapter hinge 4 through the drive end 302-5.

[0103] S5. Linear Displacement-Angle Conversion: Under the driving force in the Tx direction, the inner ring 4-6 of the angle output adapter hinge 4 rotates around the z-axis through the wheel-type rotating hinge structure 4-4, converting the sub-nanometer linear displacement of 0.625nm into a nanoradian-level rotation angle of 10nrad, thus completing the nanoradian angle output and realizing precise angle adjustment under external load. Under a 5kg load, the turntable can still achieve this level of angle output accuracy, and the rotation stroke can reach 200μrad.

[0104] S6. Power-off self-locking: When the turntable completes the angle adjustment and is powered off, the driving force amplified 40 times by the displacement drive hinge 201, combined with the power-off self-locking characteristic of the piezoelectric actuator 205, keeps the overall mechanism of the turntable at a fixed rotation angle, thus achieving power-off self-locking of the overall mechanism and ensuring that the turntable is not disturbed by external forces after power is cut off, maintaining angle stability.

[0105] S7. Cornering accuracy test and calibration: see attached. Figure 11 As shown, a sine plate with two plane mirrors is mounted on the inner ring 4-6 of the turntable's angle output hinge 4. A laser interferometer is used to measure the real-time displacement of the two plane mirrors during the turntable's rotation; as shown in the attached figure. Figure 12 As shown, the laser interferometer detects that the displacement distances of the two plane mirrors at both ends of the sine plate are equal in magnitude and opposite in direction per step; by converting the displacement difference between the two plane mirrors to an arcsine of the straight-line distance between the two mirrors, the actual rotation angle of the turntable is obtained (as shown in the attached figure). Figure 13 As shown in the figure, the rotation angle output accuracy of the turntable is tested and calibrated. In this embodiment, the rotation angle generated by the turntable step 1 is accurately 10 nrad after calibration.

[0106] After calibration in step S7, closed-loop control of the turntable angle can be achieved: the capacitive sensor 103 installed on the adapter 101 cooperates with the capacitive sensor plate 207 to detect the linear displacement in the x-direction of the displacement output block 201-8 in the middle of the displacement drive hinge 201 in real time; based on the one-to-one correspondence between linear displacement and rotation angle, the detected displacement data is converted into the real-time rotation angle of the turntable; the external control terminal compares the real-time rotation angle with the target rotation angle, calculates the angle deviation value, and adjusts the step size and direction of the y-direction input displacement of the piezoelectric actuator 205 in real time according to the deviation value, thereby achieving closed-loop control of the turntable angle and further improving the angle adjustment accuracy and stability of the turntable.

[0107] The above is an exemplary description of the invention. Obviously, the specific implementation of the invention is not limited to the above-described manner. Any non-substantial improvement made using the inventive concept and technical solution of the invention, or the direct application of the inventive concept and technical solution to other situations without modification, is within the protection scope of the invention.

Claims

1. A high-precision nanoradian turntable compatible with ultra-high vacuum, characterized in that, include: The components include a transition base assembly (1), a drive assembly (2), a displacement transmission assembly (3), and an angle output transition hinge (4). The transition base assembly (1) serves as the overall load-bearing foundation of the turntable. The drive assembly (2) and the displacement transmission assembly (3) together form the core components for drive and displacement transmission and are used to generate and transmit sub-nanometer linear displacement. The angle output transition hinge (4) is connected to the displacement transmission assembly (3) and the external load, respectively, and is used to convert linear displacement into a nano-arc-level rotation angle. The drive assembly (2) includes a displacement drive hinge (201), a pair of powerful magnets (204), and a piezoelectric actuator (205). The displacement drive hinge (201) is installed in the adapter assembly (1). The piezoelectric actuator (205) is connected to the displacement drive hinge (201) to provide nanometer-level displacement input to the turntable and has a power-off self-locking function. The pair of powerful magnets (204) is located at the connection between the piezoelectric actuator (205) and the displacement drive hinge (201) to apply a preload to ensure close contact between the two. The displacement drive hinge (201) is an integrated thin-film structure and integrates a displacement scaling hinge structure (201-6) to proportionally scale the input displacement of the piezoelectric actuator (205) and output sub-nanometer linear displacement, while amplifying the driving force by an equal multiple. The displacement transmission component (3) includes a linear displacement transmission hinge (301) and a sinusoidal drive hinge (302). The linear displacement transmission hinge (301) is fixedly connected to the displacement drive hinge (201) and the sinusoidal drive hinge (302) to transmit sub-nanometer linear displacement without loss and enhance the straightness and lateral stiffness of the displacement output. The sinusoidal drive hinge (302) is a three-segment decoupled structure and is fixedly connected to the angle output transition hinge (4) to transmit only the driving force in the Tx direction. The high-precision nanoradian turntable, consisting of the adapter assembly (1), drive assembly (2), displacement transmission assembly (3) and angle output adapter hinge (4), is adapted to ultra-high vacuum environment. Under a 5kg load, it can achieve a minimum rotation step of 10nrad and a rotation stroke of 200μrad. Furthermore, the amplified driving force of the displacement drive hinge (201) combined with the power-off self-locking characteristic of the piezoelectric actuator (205) enables the overall mechanism to achieve power-off self-locking.

2. The high-precision nanoradius turntable compatible with ultra-high vacuum according to claim 1, characterized in that, The displacement driving hinge (201) includes an overall frame (201-1), an input end (201-2), and a displacement guiding hinge (201-5). The system comprises an input end two (201-7), an intermediate displacement output block (201-8), and a displacement guide hinge two (201-9). The intermediate displacement output block (201-8) is located inside the overall frame (201-1). The first displacement guide hinge (201-5) and the second displacement guide hinge (201-9) are respectively located at both ends of the intermediate displacement output block (201-8) and connected to the overall frame (201-1) to ensure the straightness of the intermediate displacement output block (201-8) moving in the x-direction. The first input end (201-2) and the second input end (201-7) are symmetrically located on both sides of the intermediate displacement output block (201-8) inside the overall frame (201-1) and connected to the output end of the piezoelectric actuator (205) to receive the y-direction displacement input by the piezoelectric actuator (205). The displacement scaling hinge structure (201-6) is located in the overall frame (201-1). The 201-1) is internal and connected to input terminal 1 (201-2) and input terminal 2 (201-7). Both ends of the 201-1 are provided with sheet-like hinges with preset eccentricity. The displacement scaling factor is determined by the size of the eccentricity. The 201-1 is used to convert the input displacement in the y direction into the x direction and scale it proportionally. The intermediate displacement output block (201-8) is connected to the displacement scaling hinge structure (201-6) and is used to output the scaled x-direction sub-nanometer linear displacement. The intermediate displacement output block (201-8) is provided with a screw through hole 1 (201-10) and is used to realize the detachable connection between the displacement driving hinge (201) and the linear displacement transmission hinge (301). The displacement driving hinge (201) can scale the 25nm step displacement input by the piezoelectric actuator (205) in the y direction by 40 times and output a 0.625nm sub-nanometer linear displacement to the intermediate displacement output block (201-8) in the x direction.

3. The high-precision nano-arc turntable compatible with ultra-high vacuum according to claim 2, characterized in that, The linear displacement transmission hinge (301) includes an outer frame (301-1), a mounting surface (301-2), a sheet-like flexible hinge (301-3), a moving end (301-4), a threaded hole one (301-5), a pin hole one (301-6), and a threaded hole two (301-7). The outer frame (301-1) is the basic load-bearing structure of the linear displacement transmission hinge (301). The pin hole one (301-6) and the threaded hole two (301-7) are both opened on the outer frame (301-1). The threaded hole two (301-7) corresponds to the threaded locking hole provided on the outer mounting end face of the overall frame (201-1) and realizes the detachable fixed connection between the outer frame (301-1) and the overall frame (201-1) through the threaded parts. The pin hole one (301-6) The pin positioning holes on the outer mounting surface of the overall frame (201-1) correspond to the pin positioning holes, and the pins are used to achieve precise positioning of the outer frame (301-1) and the overall frame (201-1); the moving end (301-4) is connected to the outer frame (301-1) through a sheet-like flexible hinge (301-3), which is a linear displacement transmission and execution structure; the threaded hole (301-5) is opened on the moving end (301-4) to realize the movement of the moving end (301-4). 4) Detachable connection with the displacement output block (201-8) of the displacement drive hinge (201), wherein the mounting surface (301-2) is set on the upper end surface of the moving end (301-4) for mounting and fixing the sinusoidal drive hinge (302); the sheet-like flexible hinge (301-3) is an elastic connection structure for transferring motion from the plane where the displacement drive hinge (201) is located to the upper moving end (301-4) of the linear displacement transmission hinge (301).

4. The high-precision nanoradius turntable compatible with ultra-high vacuum according to claim 3, characterized in that, The sinusoidal drive hinge (302) includes a fixed end (302-2), hinge structure one (302-3), hinge structure two (302-4), and a drive end (302-5). The fixed end (302-2) is detachably fixed to the mounting surface (301-2) of the linear displacement transmission hinge (301), serving as the fixed foundation for the sinusoidal drive hinge (302). The drive end (302-5) is connected to the inner ring of the angle output transition hinge (4), serving as the output structure for the driving force. The hinge structure one (302-3) and hinge structure two (302-4) are connected and perpendicular elastic hinge structures, with their ends connected to the fixed end (302-2) and the drive end (302-5) respectively. This is used to decouple the five degrees of freedom Rx, Ry, Rz, Ty, and Tz, retaining only the Tx degree of freedom required for driving, ensuring that the driving force is transmitted unidirectionally to the angle output transition hinge (4) along the Tx direction.

5. The high-precision nanoradius turntable compatible with ultra-high vacuum according to claim 4, characterized in that, The angle output adapter hinge (4) includes an outer frame (4-1) and an inner ring (4-6); the outer frame (4-1) is mounted on the fixed end (302-2) of the displacement transmission component (3), and the upper end face of the outer frame (4-1) is provided with a threaded through hole 1 (4-2) and a pin hole 2 (4-3), which are used for positioning and detachable assembly of the outer frame (4-1) and the fixed end (302-2), respectively; the side end face of the outer frame (4-1) is provided with a threaded hole 3 (4-5), which is used to realize the detachable connection between the angle output adapter hinge (4) and the adapter assembly (1); a central hole is provided in the center of the outer frame (4-1), and the inner ring (4-6) is located in the central hole of the outer frame (4-1) and is connected by a wheel-type rotating hinge structure ( 4-4) is connected to the inner wall of the center hole of the outer frame (4-1) and is the angle output execution structure of the turntable, which is used to connect with the external load and rotate around the z-axis; the inner ring (4-6) is provided with a threaded through hole two (4-7) for locking the driving end (302-5) of the sinusoidal drive hinge (302) to the inner ring (4-6); the upper end face of the inner ring (4-6) is provided with a threaded hole four (4-8) and a pin hole three (4-9), which are used for precise positioning and detachable locking of the external load, respectively; the angle output transition hinge (4) is a radial plate hinge structure, which is used to improve the lateral stiffness and load-bearing capacity of the table; the wheel-type rotating hinge structure (4-4) is designed with several centrally symmetrical annular spokes to reduce the drift of the rotation center during rotation.

6. The high-precision nanoradius turntable compatible with ultra-high vacuum according to claim 5, characterized in that, The drive assembly (2) further includes a top seat (202), a tungsten carbide gasket (203), and a piezoelectric actuator mounting base (206); the top seat (202) is disposed between the piezoelectric actuator (205) and the input end one (201-2) and input end two (201-7) of the displacement drive hinge (201), serving as the basic structure for applying preload; the tungsten carbide gasket (203) is fitted onto the end face of the top seat (202) facing the piezoelectric actuator (205), for contacting the output end of the piezoelectric actuator (205) to reduce contact wear of the piezoelectric actuator (205); The strong magnets (204) are arranged with opposite poles facing each other at the corresponding positions of the top seat (202) and the displacement drive hinge (201). They apply preload force through the principle of opposite pole attraction, and the attraction force of the magnets is inversely proportional to the distance. They cooperate with the restoring force of the hinge to maintain the preload force constant within a certain range, and further ensure the tight contact between the piezoelectric actuator (205) and the tungsten carbide gasket (203). The piezoelectric actuator fixing seat (206) is arranged on the adapter assembly (1) to fix the fixing end of the piezoelectric actuator (205) and ensure the installation stability of the piezoelectric actuator (205).

7. The high-precision nanoradian turntable compatible with ultra-high vacuum according to claim 6, characterized in that, The adapter assembly (1) includes an adapter (101) and a capacitance sensor (103). The adapter (101) is the main supporting structure of the adapter assembly (1), and its side has two screw through holes (101-3) for locking the angle output adapter hinge (4) onto the adapter (101). The capacitance sensor (103) is detachably installed in the semi-circular groove at the bottom of the adapter (101) via a capacitance sensor pressure block (102). The drive assembly (2) also includes a capacitance sensor electrode plate (207), which is connected to the displacement drive. The intermediate displacement output block (201-8) of the hinge (201) is connected and cooperates with the capacitive sensor (103) to form a detection structure, which is used to detect the linear displacement in the x direction of the intermediate displacement output block (201-8) in real time. The linear displacement is in one-to-one correspondence with the rotation angle of the turntable. After calibration, the rotation angle of the turntable can be calculated from the detected displacement. The displacement driving hinge (201), linear displacement transmission hinge (301), sine drive hinge (302), and angle output transition hinge (4) are all processed by slow wire EDM to ensure the processing accuracy and integrated performance of each hinge structure.

8. The high-precision nanoradius turntable compatible with ultra-high vacuum according to claim 7, characterized in that, The capacitive sensor (103) is an ultra-high vacuum version sensor, which is adapted to the ultra-high vacuum environment with the titanium alloy structure. The displacement data detected by it can be transmitted to an external control terminal for real-time monitoring and control of the turntable angle.

9. A nanoradian angle output method, implemented based on the ultra-high vacuum compatible high-precision nanoradian turntable as described in any one of claims 6-8, characterized in that, Includes the following steps: S1. Place the opposite poles of the strong magnet pair (204) at the corresponding positions of the top seat (202) and the displacement drive hinge (201). Apply a preload force through the principle of opposite pole attraction, so that the preload force and the hinge restoring force are kept constant, ensuring that the output end of the piezoelectric actuator (205) is in close contact with the tungsten carbide pad (203) on the top seat (202). S2. The piezoelectric actuator (205) is controlled by an external control terminal to input a displacement of 25nm step size to the input end one (201-2) and input end two (201-7) of the displacement driving hinge (201) in the y direction. The displacement driving hinge (201) scales the input displacement by 40 times in the x direction through the internal displacement scaling hinge structure (201-6) with eccentricity. The intermediate displacement output block (201-8) outputs a sub-nanometer linear displacement of 0.625nm. At the same time, the displacement driving hinge (201) amplifies the driving force by the same multiple. S3. The linear displacement transmission hinge (301) receives the sub-nanometer linear displacement output by the intermediate displacement output block (201-8) through the moving end (301-4), and after being guided by the sheet-like flexible hinge (301-3), the displacement is transmitted without loss and moves linearly along the x-axis, while enhancing the lateral stiffness and straightness of the displacement output. S4. The sinusoidal drive hinge (302) receives the motion driving force of the linear displacement transmission hinge (301) through the fixed end (302-2). The driving force is decoupled in five degrees of freedom (Rx, Ry, Rz, Ty, Tz) through the mutually perpendicular hinge structure one (302-3) and hinge structure two (302-4). Only the driving force in the Tx direction is transmitted to the inner ring (4-6) of the angle output adapter hinge (4) through the drive end (302-5). S5. The inner ring (4-6) of the angle output adapter hinge (4) rotates around the z-axis through the wheel-type rotating hinge structure (4-4) under the action of the driving force in the Tx direction, converting the sub-nanometer linear displacement into a 10 nrad nano-arc-level rotation angle, completing the nano-arc-degree angle output, and realizing the precise angle adjustment of the external load. S6. When the high-precision nanoarc turntable compatible with ultra-high vacuum is powered off, the amplified driving force of the displacement drive hinge (201) is used in conjunction with the power-off self-locking characteristic of the piezoelectric actuator (205) to keep the overall mechanism of the turntable at a fixed rotation angle, thereby achieving power-off self-locking, ensuring angle stability and preventing external interference. S7. A sine plate with two plane mirrors is mounted on the turntable angle output transition hinge (4). A laser interferometer is used to measure the real-time displacement of the two plane mirrors during the turntable rotation. The arcsine conversion is performed by the displacement difference between the two plane mirrors and the straight distance between the two mirrors to complete the test and calibration of the turntable angle output accuracy.

10. The nanoradian angle output method according to claim 9, characterized in that, After calibration in step S7, the linear displacement in the x-direction of the displacement output block (201-8) in the middle of the displacement drive hinge (201) is detected in real time by the cooperation of the capacitive sensor (103) installed on the adapter (101) and the capacitive sensor plate (207). Based on the one-to-one correspondence between linear displacement and rotation angle, the detected displacement data is converted into the real-time rotation angle of the turntable. The external control terminal adjusts the step size and direction of the y-direction input displacement of the piezoelectric actuator (205) in real time according to the deviation between the actual value and the target value of the rotation angle, so as to realize the closed-loop control of the turntable rotation angle.

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