Magnetic levitation support fast mirror and control method

Abstract

The application discloses a kind of magnetic levitation support fast reflecting mirror and control method.The fast reflecting mirror includes: the base body (1) with accommodating cavity, the mirror assembly (2) of suspension arrangement, four groups of fixed stator coplanar installation support unit constitute the magnetic levitation support assembly (3), four staggered audio coil motor (4), position feedback component (5) and limit protection component (6);Control method includes: obtaining target attitude instruction, control light source emits light beam and receives feedback light spot by photoelectric detector, acquires photocurrent signal and calculates current deflection angle data, compares current deflection angle data with target attitude instruction to generate drive control signal.The application can realize non-contact support, eliminate the stiffness nonlinearity and rotation deviation defects caused by flexible hinge, effectively support suspended member in power failure to avoid physical impact, improve dynamic pointing accuracy and environmental adaptability.

Description

Technical Field

[0001] This application relates to the field of fast reflector device technology, specifically to a magnetically levitated fast reflector and its control method. Background Technology

[0002] Fast reflector devices, with their advantages of high bandwidth, small size, and fast response speed, are widely used in fields such as space laser communication, large-aperture telescopes, image stabilization, and precision beam control. With the rapid development of laser communication technology, the system has placed high demands on the accuracy of beam pointing and response frequency, making it urgent to develop fast reflector devices that combine large aperture, large rotation angle, and high precision.

[0003] Currently, most high-precision fast reflectors in the industry employ a combination of voice coil motor and piezoelectric ceramic drive, relying on flexible hinges for structural support. However, existing flexible hinge support structures have revealed limitations in practical engineering applications: firstly, as the system deflection angle increases, the rotation center of the flexible hinge will shift nonlinearly, leading to a decrease in the system's rotational and control accuracy; secondly, the flexible hinge itself has high rotational stiffness, requiring significant motor thrust during large-angle deflections, and is prone to mechanical fatigue under long-term high-frequency alternating stress. Furthermore, some existing flexible support schemes using staggered spring structures are bulky, hindering the miniaturization and high integration design of the overall optomechanical system. Moreover, most existing devices lack effective internal mechanical blocking mechanisms in the event of a system power failure, easily leading to destructive collisions between the precision working mirror and the rigid base, resulting in poor environmental adaptability and system reliability. Summary of the Invention

[0004] The purpose of this application is to propose a magnetically levitated fast reflector and its control method, which solves the problems of small deflection angle, low deflection accuracy and poor adaptability of the existing technology, so as to meet the application requirements of fast reflector devices in space laser communication and high-precision tracking platforms.

[0005] On one hand, this application provides a magnetically levitated fast reflector, comprising: a base having a receiving cavity; a reflector assembly suspended inside the base; a magnetically levitated support assembly comprising four sets of support units evenly distributed along the circumferential direction, each set of support units consisting of a stator fixed to the base and a mover fixed to the reflector assembly, which are installed opposite to each other and coplanarly; a voice coil motor assembly comprising four symmetrically distributed voice coil motors, each voice coil motor being spatially staggered with each set of support units along the circumferential direction, the voice coil motor assembly being configured to drive the reflector assembly to deflect; a position feedback component installed on the bottom surface of the receiving cavity, configured to obtain angle change data through a small reflector linking the reflector assembly; and a limit protection component comprising a mirror base guide groove disposed on the outer side of the reflector assembly and a mechanical limit block fixed to the inner wall of the base.

[0006] In one alternative embodiment, the stator includes a coil holder and a support coil wound on the coil holder; the mover includes an iron core fixedly mounted on the bottom of the reflector assembly and a permanent magnet attached to the side of the iron core; the stator and the mover form a non-contact support structure through magnetic coupling.

[0007] In one optional embodiment, the magnetization direction of the permanent magnet is perpendicular to the axial direction of the support coil, and a first assembly gap is reserved between the permanent magnet and the support coil; the closed magnetic circuit formed by the iron core and the permanent magnet in each support unit generates an interaction force with the support coil, the radial magnetic attraction force generated by the four support units in the coplanar state cancels each other out, the axial magnetic attraction force generated is balanced with the gravity of the reflector assembly, and a working air gap is maintained between the reflector assembly and each stator.

[0008] In one optional embodiment, each voice coil motor and each adjacent support unit are staggered at 45 degrees along the circumference of the base; the position feedback component also includes a light source and a photodetector; a small reflector is fixed at the bottom center of the reflector assembly, and the light source and photodetector are symmetrically mounted on the bottom surface of the receiving cavity and form a V-shaped light path.

[0009] In one optional embodiment, a star-shaped magnetothermal decoupling isolation structure is further included, the star-shaped magnetothermal decoupling isolation structure having radially distributed composite shielding ribs; the composite shielding ribs are interlaced between each voice coil motor and each adjacent support unit.

[0010] In one alternative embodiment, the composite shielding rib is made of a laminated structure with an aluminum nitride ceramic skeleton covered with a permalloy layer; the bottom root end of the composite shielding rib is connected to a heat dissipation backplate disposed at the bottom of the substrate, and a second assembly gap is maintained between the top end of the composite shielding rib and the bottom surface of the reflector assembly.

[0011] In one optional embodiment, the mechanical limiting block has a protrusion on the side facing the mirror assembly, the protrusion is fitted inside the mirror base guide groove and maintains a sliding fit with the inner wall of the mirror base guide groove; when the mirror assembly reaches the limit deflection position, the mechanical limiting block abuts against the end of the mirror base guide groove.

[0012] On the other hand, embodiments of this application provide a control method for a magnetically levitated fast reflector, applied to the aforementioned magnetically levitated fast reflector, wherein the position feedback component includes a light source and a photodetector, and the control method includes: acquiring a target attitude command; controlling the light source to emit a light beam, and receiving the feedback light spot reflected by a small reflector through the photodetector to collect a photocurrent signal; calculating the current deflection angle data of the reflector assembly based on the photocurrent signal; comparing the current deflection angle data with the target attitude command to generate a drive control signal, and outputting the drive control signal to a voice coil motor assembly to drive the reflector assembly to deflect.

[0013] In one optional implementation, the photodetector is a four-quadrant photodetector; the current deflection angle data of the reflector assembly is calculated based on the photocurrent signal, including: acquiring the first photocurrent, second photocurrent, third photocurrent, and fourth photocurrent output by the four quadrants of the four-quadrant photodetector respectively; inputting the first photocurrent, second photocurrent, third photocurrent, and fourth photocurrent into a digital signal processing device to perform differential ratio calculation to obtain the azimuth offset and elevation offset.

[0014] In one optional implementation, the differential ratio calculation includes: summing the first photocurrent and the fourth photocurrent and subtracting the sum of the second photocurrent and the third photocurrent to obtain a first current difference; dividing the first current difference by the sum of the photocurrents in the four quadrants to obtain a first ratio that is directly proportional to the azimuth angle offset; summing the first photocurrent and the second photocurrent and subtracting the sum of the third photocurrent and the fourth photocurrent to obtain a second current difference; dividing the second current difference by the sum of the photocurrents in the four quadrants to obtain a second ratio that is directly proportional to the pitch angle offset.

[0015] In summary, the magnetically levitated fast reflector and control method provided in this application have at least the following beneficial effects:

[0016] On the one hand, the magnetic levitation support assembly of this application adopts a non-contact architecture with four sets of fixed and moving elements mounted coplanarly, and uses the air gap magnetic coupling force generated by the bias magnetic flux to levitate the reflector assembly. This pure magnetic levitation support eliminates the stiffness nonlinearity and rotation center offset defects caused by traditional flexible hinges, improves the upper limit of the deflection angle and the pointing control accuracy under high frequency dynamics, and avoids the risks of mechanical friction and fatigue failure.

[0017] On the other hand, this application arranges the four voice coil motors driving the deflection of the mirror assemblies and the four magnetic levitation support units in a compact, 45-degree circular staggered arrangement in space. This spatial topology ensures multi-dimensional torque decoupling output while compressing the overall physical volume of the system, meeting the requirements of space applications for small-aperture, highly integrated opto-mechanical equipment.

[0018] Furthermore, this application utilizes a guide groove and a mechanical limiting block on the side to form a limiting protection component, which can provide physical blocking when the large-angle deflection reaches the limit point, and support the falling mirror body in the event of an unexpected power failure. This effectively prevents collision damage between precision moving parts and the base, and improves the environmental adaptability of optical equipment during transportation and under extreme working conditions. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the magnetically levitated fast reflector provided in an embodiment of the present invention.

[0020] Figure 2 This is a two-dimensional cross-sectional view of the magnetically levitated fast reflector provided in an embodiment of the present invention.

[0021] Figure 3 This is an exploded view of the internal driving structure of the magnetically levitated fast reflector provided in an embodiment of the present invention.

[0022] Figure 4 This is a partially enlarged view of the limiting and protection component of the magnetically levitated support fast reflector provided in an embodiment of the present invention.

[0023] Explanation of reference numerals in the attached drawings: 1-Base, 2-Reflector assembly, 3-Magnetic levitation support assembly, 4-Voice coil motor assembly, 5-Position feedback assembly, 6-Limit protection assembly, 101-Base, 102-Top cover, 103-Rear cover, 104-Mounting hole, 201-Mounting mirror base, 202-Working mirror body, 301-Small reflector base, 302-Coil base, 303-Support coil, 304-Iron core, 305-Permanent magnet, 401-Drive motor coil, 402-Drive motor magnet, 501-Light source, 502-Small reflector, 503-Photodetector, 504-Circuit board, 601-Mirror base guide groove, 602-Mechanical limit block. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0025] Example 1

[0026] like Figure 1 and Figure 2As shown in the figure, this application provides a physical structure for a magnetically levitated fast reflector. The device has a compact cylindrical configuration and mainly includes a substrate 1, a reflector assembly 2, a magnetically levitated support assembly 3, a voice coil motor assembly 4, a position feedback assembly 5, and a limit protection assembly 6. Through the tight spatial nesting and electromechanical coupling of the components, a frictionless, high-bandwidth beam deflection and stabilization system is constructed.

[0027] Specifically, refer to Figure 1 and Figure 2 The base 1 has a hollow internal cavity. The base 1 is assembled from multiple structural components, with its main body being a cylindrical base 101. An annular top cover 102 is detachably fixed to the upper edge of the base 101 using fastening screws. A through hole is provided in the center of the top cover 102; the diameter of this hole is slightly larger than the outer diameter of the working mirror body 202 within the enclosed reflector assembly 2, thus protecting the internal components without obstructing the entry and exit of the working optical path. A rear cover 103, which closes the cavity, is detachably provided at the bottom of the lower end of the base 101. For docking with an external working platform, multiple threaded mounting holes 104 are evenly arranged circumferentially around the lower end face of the base 101.

[0028] The mirror assembly 2 is suspended within the receiving cavity of the base 101, near its top. The mirror assembly 2 includes a mounting base 201 and a working mirror body 202. The main body of the mounting base 201 includes a disc-shaped base plate, with an annular raised frame extending outwards from the upper circumference of the base plate. The working mirror body 202 is precisely fixed to the upper surface of the disc-shaped base plate of the mounting base 201 using high-strength optical adhesive and is protected by the outer annular protrusion.

[0029] Combination Figure 2 and Figure 3 To achieve high-frequency frictionless motion of the reflector assembly 2, this embodiment constructs a magnetic levitation support assembly 3. The magnetic levitation support assembly 3 is supported between the base 1 and the reflector assembly 2, and includes four sets of magnetic levitation support units evenly distributed along the circumference, as well as a small reflector mount 301 serving as a connecting element. The small reflector mount 301 is located directly below the mounting base 201 and is fixed to the center of the bottom surface of the mounting base 201.

[0030] Each magnetic levitation support unit follows an electromagnetic structure with a separate mover and stator. The stator is fixedly mounted on the inner wall platform of the base 101 and includes a coil holder 302 made of non-magnetic material and a support coil 303 tightly wound and glued to the coil holder 302. Correspondingly, the mover is mounted on the movable side and consists of two iron cores 304 fixed relative to each other between the upper end face of the small reflector holder 301 and the lower end face of the reflector assembly 2. A permanent magnet 305 is fixedly clamped at the center of the gap between the two iron cores 304. The stator component, consisting of the coil holder 302 and the support coil 303, is radially opposite to the mover component, consisting of the iron cores 304 and the permanent magnet 305.

[0031] Based on this, the stators and movers in the four sets of magnetic levitation support units are strictly constrained and coplanarly mounted on the same horizontal cross section. This coplanar arrangement is the core geometric prerequisite for ensuring high-frequency rotation accuracy. The magnetization direction of the permanent magnet 305 is perpendicular to the axial direction of the support coil 303. In physical assembly, a first assembly gap is reserved between the outer wall of the permanent magnet 305 and the inner wall of the support coil 303 to allow for slight radial sway tolerance. In the working state, the biased closed magnetic circuit formed by the iron core 304 and the permanent magnet 305 in each set of support units will cut through the air gap and generate an interaction force with the support coil 303. Based on the centrally symmetrical topological arrangement of the four sets of support units, when the system is powered on and maintained at zero position, the radial magnetic attraction forces generated by these four sets of support units in the coplanar state are mutually balanced and canceled out, while the active axial magnetic attraction force they jointly generate is precisely equal to and opposite in direction to the gravity of the levitation body, thereby lifting the reflector assembly 2 and maintaining a stable and non-contact working air gap between its lower surface and the upper surface of each stator.

[0032] Furthermore, to accommodate optical loads of varying apertures and masses, those skilled in the art can adjust the rotational stiffness of the magnetic levitation support structure according to dynamic control requirements. This rotational stiffness is not only linked to the closed-loop control bandwidth, but at the hardware level, by increasing the number of turns in the support coil 303, increasing the diameter of the enameled wire, or expanding the effective cross-sectional area of ​​the iron core 304 and the permanent magnet 305, the bias magnetic flux density between the stator and mover can be effectively increased, thereby increasing the motor output force and the corresponding restoring torque stiffness around the X-axis or Y-axis. Through this directional adjustment of hardware-level parameters, the drawback of the unadjustable stiffness of mechanical hinges can be avoided, enhancing the system's environmental adaptability to various operating frequency bands.

[0033] Continue reading Figure 3Based on achieving hydrostatic levitation, a voice coil motor assembly 4 is integrated into the system to drive the reflector assembly 2 to perform two-dimensional spatial deflection around two orthogonal rotation axes. The voice coil motor assembly 4 comprises four voice coil motors that are spatially mirror-symmetrical about the X and Y axes. In terms of structural topology, to accommodate a high-power-density drive source within the limited cylindrical cavity, these four voice coil motors and the aforementioned four sets of magnetic levitation support units are spatially staggered at 45-degree intervals along the circumference of the base 1.

[0034] Each voice coil motor consists of a stationary end and a moving end: the drive motor coil 401 is fixedly mounted in a corresponding groove at the bottom of the base 101 by screws; the corresponding drive motor magnet 402 has its output connection end interference-fitted and extends upward, directly and fixedly connected to the bottom of the mounting base 201 of the reflector assembly 2. When the servo control system supplies high-frequency currents of opposite polarity to these four sets of diagonally differentially arranged drive motor coils 401, the Lorentz force principle generates an axial push-pull couple, driving the suspended working mirror 202 to precisely deflect around its center of mass. By adopting a coplanar and staggered electromagnetic array layout, not only is the physical spatial separation and decoupling of the driving force and the levitation holding force achieved, but the axial height dimension of the entire machine is also effectively reduced.

[0035] To construct a closed-loop attitude control circuit, a position feedback component 5 is hidden deep within the bottom surface of the housing cavity. Figure 2 The position feedback component 5 includes a circuit board 504, which serves as a signal detection hub, and is fastened to the bottom surface of the base 101 near the rear cover 103 by screws. A light source 501 and a photodetector 503 are symmetrically mounted at a specific angle on the central protrusion of the bottom surface of the base 101.

[0036] To synchronously sense the microscopic attitude of the moving parts, a small reflector 502 is inverted and fixed at the center of the lower end face of the small reflector mount 301 using optical-grade adhesive. In the optical link design, the collimated measurement beam emitted by the light source 501 is projected obliquely upwards, and its optical path normal accurately intersects at the center of the reflective surface of the small reflector 502. After being reflected by the small reflector 502, the beam forms an echo spot and falls precisely onto the target surface of the photodetector 503, thus constructing an internally hidden V-shaped closed-loop feedback optical path. In addition, based on the needs of system integration, in addition to the front signal line of the photodetector 503, the power supply cable of the drive motor coil 401, the control line of the light source 501, etc., all pass through the pre-reserved dark holes inside the base 101 and are uniformly plugged into and converged on the circuit board 504, which performs the analog-to-digital conversion sampling and power amplification interaction tasks of the signal. This wiring layout effectively prevents parasitic interference caused by messy internal leads to the air gap magnetic field and avoids cable fatigue damage under high-frequency vibration.

[0037] Reference Figure 4 As a long-stroke suspension motion system, loss of control or power failure leading to a fall poses a potential risk of damage. Therefore, this embodiment integrates a purely mechanical limiting and protection component 6 around the periphery of the mechanism. The limiting and protection component 6 mainly includes multiple mirror mount guide grooves 601 and multiple matching mechanical limiting blocks 602. The four mirror mount guide grooves 601, as concave features, are evenly distributed in pairs around the outer periphery of the mounting mirror mount 201 along the rotation axes of the X and Y axes.

[0038] Correspondingly, one end of each of the four mechanical limiting blocks 602 is fixed to a protruding support column on the inner wall of the base 1, and the other end extends inward as a cantilever structure with a rigid protrusion. This protrusion accurately fits into the internal space of the mirror base guide groove 601, and within the normal levitation working air gap range, the inner walls maintain a non-contact sliding fit relationship with a small slip tolerance. The mechanical physical action of this fit structure is as follows: when the system is powered on and the working mirror 202 reaches the software-preset limit deflection angle, the physical boundaries of the upper and lower end faces of the two sets of mirror base guide grooves 601 will directly abut against the upper and lower surfaces of the mechanical limiting blocks 602 inserted therein, using the rigid collision of metal to cut off the tendency of it to continue deflection, thus achieving hard limiting; when the system encounters a sudden power failure, the magnetic levitation attraction disappears, and the entire reflector assembly 2 will fall vertically along the vertical guide surface of the mirror base guide groove 601 under the action of gravity, and finally sit stably on the supporting surface of the mechanical limiting block 602. By setting this limiting and matching relationship, the suspension component can be effectively supported in the event of a power failure, preventing the precision optical working parts from colliding and breaking with the hard base, thus enhancing the equipment's resistance to damage.

[0039] It should be noted that the aforementioned square fitting structure of the mirror mount guide groove and the mechanical limiting block is merely an example. Those skilled in the art may also use similar alternative configurations such as cylindrical pins and elliptical grooves, as long as they can achieve the physical limiting purpose of extreme angle collision prevention and vertical support in the event of power failure, they are all included within the scope of protection of this application.

[0040] In an alternative advanced implementation, considering that the system integrates the voice coil motor and magnetic levitation coil into a small cavity through a compact 45-degree spatial staggered layout, when the voice coil motor is injected with a high-frequency, high-current to perform a step response, its drive coil will inevitably generate an alternating high-frequency leakage magnetic field, accompanied by irreversible heat accumulation. If multi-physics crosstalk intrudes into the air gap of adjacent magnetic levitation stator and mover, it will distort the support stiffness, and thermal expansion will cause the mounting reference surface of the bottom photodetector to drift to zero position, destroying the pointing accuracy. To eliminate this potential defect, this embodiment adds a radially octagonal star-shaped magnetothermal decoupling isolation structure on the internal step of the base 101, along the circumferential direction between each drive motor coil 401 and the adjacent support coil 303.

[0041] The core framework of this star-shaped magnetocaloric decoupling isolation structure is a labyrinthine, intersecting composite shielding rib. In terms of materials and layered microstructure, this composite shielding rib is fabricated using a composite lamination process. The inner core layer uses an aluminum nitride ceramic framework with high thermal conductivity to rapidly conduct the heat accumulated in the stator downwards along the path of least resistance. On the outer surface of this ceramic framework, a permalloy shielding layer with high magnetic permeability is applied using vacuum deposition or edge-wrapping processes. The thickness of this shielding layer is controlled between 0.5 mm and 1.2 mm to provide a low magnetic reluctance return circuit, confining the divergent magnetic lines of force generated by the voice coil motor within a local quadrant.

[0042] In terms of spatial dimensions, the bottom root of the composite shielding rib uses high thermal conductivity adhesive or screw connection to directly couple with the heat dissipation cover 103 attached to the bottom of the substrate 1, forming a low thermal resistance dissipation channel. Simultaneously, to avoid frictional interference, the top end of the upward-growing composite shielding rib is controlled to be truncated, precisely maintaining a non-contact second assembly gap of approximately 0.2mm to 0.5mm between it and the bottom surface of the suspended reflector assembly 2 above. Through this composite shielding rib with its specific material and micro-gap design, not only is a rigid barrier constructed in physical space, but also, at the electromagnetic and thermodynamic levels, efficient bypass absorption of adjacent high-frequency alternating magnetic fields and directional rapid drainage of retained heat are achieved. Based on this design, the system can create an ultra-stable microenvironment with pure magnetic field lines and constant temperature for the core optical position feedback component responsible for calculation at the bottom layer, eliminating the distortion of the reference constant caused by thermal deformation and ensuring the pointing accuracy of the equipment under high-dynamic and demanding operating conditions.

[0043] Example 2

[0044] Based on the opto-electro-mechanical physical architecture disclosed in Embodiment 1 above, in order to achieve closed-loop, precise beam deflection control with high anti-interference capability, this embodiment further proposes a control method applied to the aforementioned magnetically levitated support fast reflector. The execution logic of this method relies on digital signal processing devices deployed on the circuit board 504 at the bottom of the base, as well as related analog-to-digital conversion, power drive, and other peripheral supporting links.

[0045] After the system is powered on and completes its initial self-stabilized levitation from the zero position, this control method, relying on its built-in hardware and software links, cyclically executes closed-loop attitude correction actions. Specifically, this method acquires externally issued target attitude commands containing precise coordinate values. These commands characterize the specific spatial pointing state that the optical payload is expected to enter.

[0046] Simultaneously with receiving instructions, the control system's underlying layer is configured to drive the light source 501 to constantly emit a collimated measurement beam. This beam passes through the internal hollow corridor and is projected onto a small, servo-driven reflector 502. Accompanied by a momentary, minute tumble of the working mirror 202, it reflects a feedback spot carrying spatial angular parameters with an amplified offset. This feedback spot is captured by the photosensitive target of a photodetector 503 mounted at an angle on the underlying layer, thereby acquiring and exciting a real-time transient photocurrent signal.

[0047] Because the energy centroid coordinates of the feedback spot on the target surface are highly correlated with the deflection angle of the working mirror 202 in two-dimensional space, the processor module is configured to acquire the raw analog currents output by the four independently divided photosensitive quadrant arrays (A, B, C, and D) on the target surface of the four-quadrant photodetector. To meet the processor's computational requirements, a transimpedance amplifier preamplifier circuit is set at the bottom layer to filter high-frequency ambient white noise, and the corresponding digitized first photocurrent I is extracted and latched through an analog-to-digital converter circuit. A Second photocurrent I B Third photocurrent I C and the fourth photocurrent I D .

[0048] Subsequently, the photocurrent data from these four isolated quadrants were I A I B I C and I D The input is fed into the arithmetic logic unit of the digital signal processing device to perform the differential ratio calculation process, so as to decouple and extract the current azimuth and elevation angle offset of the mirror.

[0049] The specific mathematical implementation and logical flow steps of the core attitude calculation algorithm are as follows:

[0050] To obtain the azimuth offset, the processor performs the first channel operation. The first photocurrent I, representing the energy density of the light spot on the same side, is processed by an adder. A With the second photocurrent I B Perform a summation operation, and simultaneously calculate the third photocurrent I on the opposite side. C With the fourth photocurrent I D Perform a summation operation; subtract the sums on both sides, i.e., subtract the sum of the latter from the sum of the former, to extract the absolute error energy characterizing the one-dimensional spatial position misalignment; in order to eliminate common-mode gain interference caused by fluctuations in the light source's luminous power or environmental attenuation, divide the first current difference by the sum of the photocurrents in the four quadrants ( The normalization process is performed to extract the first ratio that is highly proportional to the actual azimuth offset.

[0051] To obtain the final azimuth attitude data Introducing an optomechanical proportionality constant K, pre-calibrated based on the specific optical path focal length and the physical dimensions of the detector target surface. x Specifically, the system performs calculations for the azimuth offset:

[0052]

[0053] Similarly, to obtain the pitch angle offset, the processor performs a second-channel operation based on orthogonal mirror logic. This is achieved by analyzing the first photocurrent I, which represents another vertical dimension. A With the third photocurrent I C Summing is performed, and the second photocurrent I is subtracted. B With the fourth photocurrent I D The summation value is used to extract the second current difference. Similarly, the second current difference is divided by the sum of the photocurrents in the four quadrants for normalization and stripping, resulting in a second ratio that is directly proportional to the pitch angle offset.

[0054] Combined with the calibrated longitudinal axis optical mechanism proportionality constant K y Specifically, the system performs calculations for the pitch angle offset:

[0055]

[0056] In the attitude calculation architecture given in the above embodiments, each constant needs to be matched according to the specific engineering system. For example, in this application for a 50mm aperture-level fast reflector, due to the limitations of the folded focal length of the internal V-shaped optical path and the quadrant dead zone width of commercial photodetectors, the constant K... x With K y The value range is configured and calibrated to be between 0.02 rad / A and 0.08 rad / A to ensure that it still has a distortion-free linear mapping capability under deviations at the microradian level.

[0057] After the digital signal processing device completes the transient extraction of the current deflection angle data, the control method enters the execution closed loop. The processor compares the difference between the parsed current attitude and the initially acquired target attitude command in the register, and after filtering and modulation by proportional-integral-derivative or active disturbance rejection control algorithms, generates a digital drive control signal with direction and amplitude indication. This control signal is converted into a strong current excitation by a digital-to-analog converter and an externally bridged power amplifier circuit, and is cross-output to a specific drive motor coil 401 in the voice coil motor assembly 4. The energized coil experiences a net torque generated by the Ampere force in the magnetic field, driving the suspended reflector assembly 2 to deflect in the direction of error reduction. By repeatedly cycling the closed-loop steps within a clock cycle until the error approaches zero, high-precision pointing and anti-jitter stabilization of the space beam are achieved.

[0058] Based on the detailed structural and control method embodiments described above, the collaborative working principle of the device and method described in this application can be summarized as follows: The system utilizes four sets of magnetically levitated support units with separated stationary and moving parts and no mechanical friction to firmly hold the core moving part carrying the optical lens level and suspend it in the inner cavity space; subsequently, high-power density voice coil motors staggered at a 45-degree angle in space are used to perform high-frequency push-pull drive; during the movement, the built-in light source uses the miniature optical path at the bottom of the target surface to project a reference point, and in conjunction with the four-quadrant differential ratio calculation algorithm, acts as a highly sensitive electronic eye, converting weak deflections into electrical signals in real time for core calculation and calibration; during this period, once a risk of overstepping boundaries or power failure is encountered, the mechanical protrusion slots lurking on the periphery will seamlessly take over and absorb the impact energy; at the same time, a special isolation frame is used to prevent multi-source internal interference. This system, which deeply couples light, mechanics, magnetism, and electricity, constructs a frictionless, anti-hard impact, low-drift platform with high-frequency intrinsic sensing capabilities within a limited volume.

Claims

1. A magnetically levitated fast-reflecting mirror, characterized in that, include: The substrate (1) has a receiving cavity; The reflector assembly (2) is suspended inside the receiving cavity; The magnetic levitation support assembly (3) includes four sets of support units evenly distributed along the circumference. Each set of support units is composed of a stator fixed to the base (1) and a mover fixed to the reflector assembly (2) installed opposite to each other and on the same plane. The voice coil motor assembly (4) includes four symmetrically distributed voice coil motors. Each of the voice coil motors is staggered with each of the support units along the circumferential direction in spatial position. The voice coil motor assembly (4) is configured to drive the reflector assembly (2) to deflect. A position feedback component (5) is installed on the bottom surface of the receiving cavity and is configured to obtain angle change data by means of a small reflector fixed to the bottom of the reflector assembly (2); The limiting protection component (6) includes a mirror mount guide groove disposed on the outer side of the reflector assembly (2) and a mechanical limiting block fixed to the inner wall of the base (1).

2. The magnetically levitated fast-reflecting mirror as described in claim 1, characterized in that, The stator includes a coil base and a support coil wound on the coil base; the mover includes an iron core fixedly installed at the bottom of the reflector assembly (2) and a permanent magnet attached to the side of the iron core; the stator and the mover form a non-contact support structure through magnetic coupling.

3. The magnetically levitated fast-reflecting mirror as described in claim 2, characterized in that, The magnetization direction of the permanent magnet is perpendicular to the axial direction of the support coil, and a first assembly gap is reserved between the permanent magnet and the support coil; the closed magnetic circuit formed by the iron core and the permanent magnet in each support unit generates an interaction force with the support coil; the radial magnetic attraction force generated by the four support units in the coplanar state cancels each other out; the axial magnetic attraction force generated is balanced with the gravity of the reflector assembly (2); and a working air gap is maintained between the reflector assembly (2) and each stator.

4. The magnetically levitated fast-reflecting mirror as described in claim 1, characterized in that, Each of the voice coil motors and the adjacent support units are staggered at 45 degrees along the circumference of the base (1); the position feedback component (5) also includes a light source and a photodetector; the small reflector is fixed at the bottom center of the reflector assembly (2), and the light source and the photodetector are symmetrically installed on the bottom surface of the receiving cavity and form a V-shaped light path.

5. The magnetically levitated fast-reflecting mirror as described in claim 4, characterized in that, It also includes a star-shaped magnetothermal decoupling isolation structure, which has radially distributed composite shielding ribs; the composite shielding ribs are interlaced between each of the voice coil motors and each of the adjacent support units.

6. The magnetically levitated fast-reflecting mirror as described in claim 5, characterized in that, The composite shielding rib is made of a layered structure with an aluminum nitride ceramic skeleton covered with a permalloy layer; the bottom root end of the composite shielding rib is connected to the heat dissipation backplate located at the bottom of the substrate (1), and a second assembly gap is maintained between the top end of the composite shielding rib and the bottom surface of the reflector assembly (2).

7. The magnetically levitated fast-reflecting mirror as described in claim 1, characterized in that, The mechanical limiting block has a protrusion on the side facing the mirror assembly (2). The protrusion is fitted into the mirror base guide groove and maintains a sliding fit with the inner wall of the mirror base guide groove. When the mirror assembly (2) reaches the limit deflection position, the mechanical limiting block abuts against the end of the mirror base guide groove.

8. A control method for a magnetically levitated fast reflector, applied to a magnetically levitated fast reflector as described in any one of claims 1 to 7, wherein the position feedback component (5) comprises a light source and a photodetector; characterized in that, include: Obtain target attitude command; The light source is controlled to emit a light beam, and the feedback light spot reflected by a small mirror is received by a photodetector to collect the photocurrent signal. The current deflection angle data of the reflector assembly (2) is calculated based on the photocurrent signal; The current deflection angle data is compared with the target attitude command to generate a drive control signal, and the drive control signal is output to the voice coil motor assembly (4) to drive the reflector assembly (2) to deflect.

9. The method as described in claim 8, characterized in that, The photodetector is a four-quadrant photodetector; The calculation of the current deflection angle data of the reflector assembly (2) based on the photocurrent signal includes: The first photocurrent, second photocurrent, third photocurrent, and fourth photocurrent output in the four quadrants of the four-quadrant photodetector are obtained respectively. The first photocurrent, the second photocurrent, the third photocurrent, and the fourth photocurrent are input into a digital signal processing device to perform differential ratio calculation, thereby obtaining the azimuth offset and the elevation offset.

10. The method as described in claim 9, characterized in that, The differential ratio calculation includes: By summing the first photocurrent and the fourth photocurrent and subtracting the sum of the second photocurrent and the third photocurrent, the first current difference is obtained. The first current difference is then divided by the sum of the photocurrents in the four quadrants to obtain the first ratio that is directly proportional to the azimuth offset. By summing the first photocurrent and the second photocurrent and subtracting the sum of the third photocurrent and the fourth photocurrent, a second current difference is obtained. Dividing the second current difference by the sum of the photocurrents in the four quadrants yields a second ratio that is directly proportional to the pitch angle offset.

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