A large-stroke high-bandwidth precision compound-axis beam scanning device and a control method thereof

Abstract

The application relates to a large-stroke high-bandwidth precise composite-axis light beam scanning device and a control method thereof, and belongs to the field of optical instruments. The device comprises a laser, a micro-motion fast mirror, a macro-motion fast mirror, a PSD position sensor and a controller. The controller comprises a frequency domain instruction signal distribution module, a low-frequency feedforward instruction module, a deflection instruction driving module, a light beam point position sensing estimation module and a high-frequency feedback error distribution module. The application proposes a control method suitable for a macro-micro two-stage four-degree-of-freedom redundant light beam scanning system, designs a double-butterfly-shaped controller to comprehensively control two-stage mechanisms with different dynamic characteristics, realizes adaptive adjustment of closed-loop bandwidth under different strokes through dynamic cooperation of the macro-micro two-stage mechanisms, the system bandwidth is close to the performance of the micro-motion fast mirror in the micro-motion range, the macro-motion fast mirror keeps the covering capacity under the condition of large stroke, and the influence of macro-motion fast mirror measurement noise on system precision can be effectively inhibited.

Description

Technical Field

[0001] This invention relates to a large-stroke, high-bandwidth precision composite axis beam scanning device and its control method, belonging to the field of optical instruments. Background Technology

[0002] Beam scanning devices are widely used in semiconductor processing, laser communication, laser fabrication, and biomedical equipment. They typically employ galvanometers or fast-reflecting mirrors as the beam deflection actuators. With the development of semiconductor and laser processing technologies, higher demands are being placed on the stroke, bandwidth, and accuracy of beam scanning devices. Traditional galvanometers and single fast-reflecting mirror mechanisms, due to limitations in their driving principles, are increasingly unable to simultaneously meet the technical requirements of large stroke and high bandwidth.

[0003] There is an inherent contradiction between the closed-loop bandwidth, stroke, and motion accuracy of a beam scanning system, making it difficult to simultaneously meet all high-performance requirements. Multi-stage composite axes offer an effective solution to this problem.

[0004] Current composite axis beam scanning systems mainly use galvanometers as the execution unit. Due to the inherent defect of the low resonant frequency of the galvanometer mechanism, although a large actuation stroke can be guaranteed, its closed-loop bandwidth and control accuracy are difficult to achieve. Summary of the Invention

[0005] To address the problem of simultaneously failing to guarantee stroke, bandwidth, and accuracy, this invention proposes a large-stroke, high-bandwidth precision composite axis beam scanning device and its control method.

[0006] The technical solution adopted by the present invention to solve the above problems is as follows: The present invention includes a laser, a micro-motion fast-reflection mirror, a macro-motion fast-reflection mirror, a PSD position sensor, and a controller;

[0007] The micro-motion fast-reflection mirror includes a micro-motion mirror, a micro-motion mirror support, a micro-motion mirror driver, and a micro-motion mirror sensor;

[0008] The micromirror is rotatably connected to the micromirror support; the micromirror driver is connected to the micromirror and is used to drive the micromirror to deflect around the horizontal and vertical axes;

[0009] The micromirror sensor is used to measure the horizontal deflection angle of the micromirror surface. Vertical deflection angle of the micro-moving mirror surface ;

[0010] The macro-motion fast-reflection mirror includes a macro-motion mirror, a macro-motion mirror bracket, a macro-motion mirror driver, and a macro-motion mirror sensor;

[0011] The macro-motion mirror is rotatably connected to the macro-motion mirror bracket; the macro-motion mirror driver is connected to the macro-motion mirror and is used to drive the macro-motion mirror to deflect around the horizontal axis and the vertical axis;

[0012] The macro-motion mirror sensor is used to measure the horizontal deflection angle of the macro-motion mirror surface. Vertical deflection angle of macroscopic mirror surface ;

[0013] The laser, the micro-motion fast-reflecting mirror, the macro-motion fast-reflecting mirror, and the PSD position sensor are arranged in sequence at intervals, so that the laser beam emitted by the laser irradiates the center of the mirror surface of the micro-motion mirror, and after reflecting a first reflected beam, it irradiates the center of the mirror surface of the macro-motion mirror, and after reflecting a second reflected beam, it irradiates the receiving plane of the PSD position sensor perpendicularly.

[0014] The controller includes a frequency domain command signal allocation module, a low-frequency feedforward command module, a deflection command driving module, a beam point position sensing estimation module, and a high-frequency feedback error allocation module.

[0015] The frequency domain command signal allocation module is used to assign the preset two-dimensional coordinate command signal of the beam point position on the receiving plane of the PSD position sensor to the input signal. , The low-frequency command signal is assigned as a two-dimensional coordinate system based on the preset beam point position according to the frequency components. , and the high-frequency command signal of the two-dimensional coordinates of the preset beam point position , ;

[0016] The low-frequency feedforward command module is used to transmit the preset beam point position coordinates low-frequency command signal according to the principle of stroke allocation, based on the inverse kinematics principle of the two-stage optical path. , The horizontal deflection angle is preset by converting inverse kinematics into a micromirror feedforward command. Preset vertical deflection angle for micromirror feedforward command Preset horizontal deflection angle for macro-mirror feedforward command Macro-mirror feedforward command preset vertical deflection angle ;

[0017] The deflection command driving module is used to... and The micromirror driver is controlled to drive the micromirror to deflect accordingly around the vertical and horizontal axes, and according to... and The macro mirror driver is controlled to drive the macro mirror to deflect accordingly around the vertical and horizontal axes;

[0018] The beam point position sensing and estimation module is used to... , , , Subtract respectively , , , The horizontal feedforward angle deflection error of the micromirror was obtained. Vertical feedforward angle deflection error of the micromirror Macro-mirror horizontal feedforward angle deflection error Macro-mirror vertical feedforward angle deflection error Then, the two-dimensional coordinate change command signal of the preset beam point position on the receiving plane of the PSD position sensor is obtained through forward kinematics calculation. , ;

[0019] The high-frequency feedback error allocation module is used to adjust the preset two-dimensional coordinate change command signal of the beam point position. , The low-frequency horizontal correction deflection angle of the micromirror was calculated. Low-frequency vertical correction deflection angle of the micro-moving mirror Macro-mirror low-frequency horizontal correction deflection angle Macro-motion mirror low-frequency vertical correction deflection angle ;

[0020] The beam point position sensing and estimation module is used to estimate based on , , , The actual two-dimensional coordinates of the preset beam point position on the receiving plane of the PSD position sensor are obtained through forward kinematics calculations. , ;

[0021] The high-frequency feedback error allocation module is also used to determine the high-frequency command signal based on the preset two-dimensional coordinates of the beam point position. , and the actual two-dimensional coordinates of the preset beam point position , The high-frequency horizontal correction deflection angle of the micromirror was calculated. High-frequency vertical correction of deflection angle of micro-moving mirror High-frequency horizontal correction deflection angle of macro-motion mirror Macro-motion mirror high-frequency vertical correction deflection angle ;

[0022] The deflection command driving module is also used to... and , and , and , and The horizontal compensation deflection angle of the micromirror is obtained by adding them separately. Vertical compensation deflection angle of the micromirror Horizontal compensation deflection angle of macro mirror Vertical compensation deflection angle of macro mirror The micromirror driver is controlled to drive the micromirror to deflect around the vertical and horizontal axes by angles respectively. and And control the macro mirror driver to drive the macro mirror to deflect around the vertical axis and horizontal axis by angles respectively. and This is to adjust the beam point on the receiving plane of the PSD position sensor to a preset beam point position.

[0023] Furthermore, the micro-motion mirror and the macro-motion mirror are arranged parallel to each other at intervals; the laser beam emitted by the laser has an incident angle of 45° on the micro-motion mirror; the primary reflected beam has an incident angle of 45° on the macro-motion mirror.

[0024] The present invention also provides a control method for the above-mentioned large-stroke, high-bandwidth precision composite axis beam scanning device, which includes the following steps:

[0025] Step 100: The frequency domain command signal allocation module will input the preset two-dimensional coordinate command signal of the beam point position on the receiving plane of the PSD position sensor. , The low-frequency command signal is assigned as a two-dimensional coordinate system based on the preset beam point position according to the frequency components. , and the high-frequency command signal of the two-dimensional coordinates of the preset beam point position , ;

[0026] Step 200: The low-frequency feedforward command module, through the inverse kinematics principle of the two-stage optical path and according to the principle of travel allocation, transmits the low-frequency command signal of the two-dimensional coordinates of the preset beam point position. , The horizontal deflection angle is preset by converting inverse kinematics into a micromirror feedforward command. Preset vertical deflection angle for micromirror feedforward command Preset horizontal deflection angle for macro-mirror feedforward command Macro-mirror feedforward command preset vertical deflection angle ;

[0027] Step 300: The deflection command driving module according to and The micromirror driver is controlled to drive the micromirror to deflect accordingly around the vertical and horizontal axes, and according to... and The macro mirror driver is controlled to drive the macro mirror to deflect accordingly around the vertical and horizontal axes;

[0028] Step 400: The micromirror sensor measures the horizontal deflection angle of the micromirror surface. Vertical deflection angle of the micro-moving mirror surface ;

[0029] The macro-motion mirror sensor measures the horizontal deflection angle of the macro-motion mirror surface. Vertical deflection angle of macroscopic mirror surface ;

[0030] Step 500: The beam point position sensing and estimation module will... , , , Subtract respectively , , , The horizontal feedforward angle deflection error of the micromirror was obtained. Vertical feedforward angle deflection error of the micromirror Macro-mirror horizontal feedforward angle deflection error Macro-mirror vertical feedforward angle deflection error Then, the two-dimensional coordinate change command signal of the preset beam point position on the receiving plane of the PSD position sensor is obtained through forward kinematics calculation. , ;

[0031] Step 600: The high-frequency feedback error allocation module uses a preset two-dimensional coordinate change command signal for the beam point position. , The low-frequency horizontal correction deflection angle of the micromirror was calculated. Low-frequency vertical correction deflection angle of the micro-moving mirror Macro-mirror low-frequency horizontal correction deflection angle Macro-motion mirror low-frequency vertical correction deflection angle ;

[0032] Step 700: The beam point position sensing estimation module, based on... , , , The actual two-dimensional coordinates of the beam point position on the receiving plane of the PSD position sensor are obtained through forward kinematics calculations. , ;

[0033] Step 800: The high-frequency feedback error allocation module uses a preset high-frequency command signal based on the two-dimensional coordinates of the beam point position. , and the actual two-dimensional coordinates of the beam point position , The high-frequency horizontal correction deflection angle of the micromirror was calculated. High-frequency vertical correction of deflection angle of micro-moving mirror High-frequency horizontal correction deflection angle of macro-motion mirror Macro-motion mirror high-frequency vertical correction deflection angle ;

[0034] Step 900: The deflection command driving module will... and , and , and , and The horizontal compensation deflection angle of the micromirror is obtained by adding them separately. Vertical compensation deflection angle of the micromirror Horizontal compensation deflection angle of macro mirror Vertical compensation deflection angle of macro mirror The micromirror driver is controlled to drive the micromirror to deflect around the vertical and horizontal axes by angles respectively. and And control the macro mirror driver to drive the macro mirror to deflect around the vertical axis and horizontal axis by angles respectively. and This is to adjust the beam point on the receiving plane of the PSD position sensor to a preset beam point position.

[0035] Further, step 700 specifically includes:

[0036] Step 701: Calculate the mirror normal vector of the micro-moving mirror using formula (1). The mirror normal vector of the macro-motion mirror is calculated using formula (2). :

[0037] Formula (1) ;

[0038] Formula (2) ;

[0039] Step 702: Calculate the mirror normal vector of the micro-moving mirror using formulas (3) and (4). In the preset basic coordinate system coordinates in The mirror normal vector of the macro-motion mirror is calculated using formulas (5) and (6). In the preset basic coordinate system coordinates in :

[0040] Formula (3) ;

[0041] Formula (4) ,

[0042] in, Basic coordinate system To the micro-mirror coordinate system The homogeneous coordinate transformation matrix;

[0043] Formula (5) ;

[0044] Formula (6) ,

[0045] in, Basic coordinate system To the macro mirror coordinate system The homogeneous coordinate transformation matrix, For the micro-moving mirror coordinate system The origin of the coordinate system and the coordinate system of the macro mirror The distance between the origin of the coordinate system;

[0046] Step 703: Based on the incident beam Calculate the first reflected beam after reflection by the micro-moving mirror. :

[0047] Incident beam The laser beam emitted by the laser;

[0048] Representing a beam of light in three-dimensional space using the point-direction method, the incident beam... ;

[0049] The first reflected beam is calculated using formulas (7) and (8). ;

[0050] in and represents the directions of the incident beam and the first reflected beam, respectively, and is a unit-length vector; and These are any points on the incident beam and the first reflected beam, respectively.

[0051] Formula (7) ,

[0052] in, The Householder matrix represents the direction reflection transformation of the micro-mirror. It is the identity matrix;

[0053] Formula (8) ,

[0054] in, For the micro-moving mirror coordinate system From the origin of the coordinate system to the base coordinate system The distance from the origin of the coordinate system. It is the identity matrix. It is a zero vector; Let be the mirror reflection matrix of the micro-moving mirror;

[0055] Step 704: Based on the first reflected beam The secondary reflected beam after reflection by the macro-motion mirror is calculated using formulas (9) and (10) as follows: , The direction of the secondary reflected beam is given by , and is a vector per unit length. Let be any point on the secondary reflected beam;

[0056] Formula (9) ,

[0057] in, Let be the Householder matrix for the directional reflection transformation of the macro-mirror. It is the identity matrix;

[0058] Formula (10) ,

[0059] in, For the macro mirror coordinate system From the origin of the coordinate system to the base coordinate system The distance from the origin of the coordinate system. Let be the mirror reflection matrix of the macro-motion mirror;

[0060] Step 705: Calculate the secondary reflected beam using formula (11) The actual beam point on the PSD position sensor in the base coordinate system Three-dimensional coordinates on :

[0061] Formula (11) ,

[0062] in, Let be the normal vector of the receiving plane of the PSD position sensor; , , The actual beam point in the base coordinate system X-axis, Y-axis, and Z-axis coordinates;

[0063] Step 706: Use formula (12) to obtain the three-dimensional coordinates of the actual beam point. Converted into two-dimensional coordinates on the receiving plane of the PSD position sensor. :

[0064] Formula (12) ,

[0065] in, For the micro-moving mirror coordinate system The distance from the origin of the coordinate system to the receiving plane of the PSD position sensor.

[0066] Further, step 700 specifically includes:

[0067] The actual two-dimensional coordinates of the beam point position on the PSD position sensor are calculated using formula (13). Formula (13) is:

[0068] .

[0069] Further, step 800 specifically includes:

[0070] The beam displacement on the receiving plane of the PSD position sensor caused by the micro-moving mirror reaching its maximum stroke is: , ;

[0071] Step 801: Calculate the total horizontal error of the beam point on the receiving plane of the PSD position sensor along the X-axis. and the total vertical error on the Y-axis Specifically:

[0072] ;

[0073] ;

[0074] Step 802: Calculate the total horizontal error. and total vertical error The micro-motion mirror and the macro-motion mirror are assigned, and the horizontal error of the micro-motion mirror is calculated. Horizontal error of macro mirror Vertical error of the micromirror Vertical error of macro mirror Specifically:

[0075] when hour, , ;

[0076] when hour, , ;

[0077] when hour, , ;

[0078] when hour, , ;

[0079] when hour, , ;

[0080] when hour, , ;

[0081] Step 803: Calculate the high-frequency horizontal correction deflection angle of the micromirror. High-frequency vertical correction of deflection angle of micro-moving mirror High-frequency horizontal correction deflection angle of macro-motion mirror Macro-motion mirror high-frequency vertical correction deflection angle Specifically:

[0082] The micromirror PI controller controls the horizontal error of the micromirror. Vertical error of the micromirror Converted to micromirror horizontal compensation output Vertical compensation output of micromirror Then, the high-frequency horizontal correction deflection angle of the micromirror is obtained through inverse kinematics calculation. High-frequency vertical correction of deflection angle of micro-moving mirror ;

[0083] The macro-mirror PI controller controls the macro-mirror's horizontal error. Vertical error of macro mirror Convert to macro mirror horizontal compensation output Macro-mirror vertical compensation output Then, the high-frequency horizontal correction deflection angle of the macromirror is calculated through inverse kinematics. Macro-motion mirror high-frequency vertical correction deflection angle .

[0084] Further, step 200 specifically includes:

[0085] Calculate using formulas (14) and (15) , , , ;

[0086] Formula (14) ,

[0087] in, The stroke of the micro-motion fast-reflection mirror is... The stroke of the macro-motion fast-reflection mirror, The inverse kinematic equations;

[0088] Formula (15) ,

[0089] in, , The low-frequency command signal is the two-dimensional coordinate of the preset beam point position.

[0090] The beneficial effects of this invention are:

[0091] 1. Compared with the traditional composite axis beam scanning system composed of a turntable / galvanometer + fast reflector, the present invention has a faster overall response speed and stronger anti-interference ability. It has a compact structure, small size, light weight, and is easy to integrate. The nonlinear coupling effect of beam pointing is smaller and easier to correct and control.

[0092] 2. This invention applies kinematic analysis to incorporate complex light transformation relationships into the closed-loop control of the system, reducing the design complexity of the control system. It can achieve high precision, high response, and high stability under different working conditions, and is suitable for fields such as laser communication, precision machining, and optical measurement.

[0093] 3. A dynamic allocation mechanism is adopted to achieve adaptive adjustment of the closed-loop bandwidth under different strokes. Within the micro-motion range, the system bandwidth is close to the performance of the micro-motion channel, while maintaining the coverage capability of the macro-motion fast-reflection mirror under large stroke conditions. Compared with traditional master-slave control, the closed-loop bandwidth of the system for small stroke command signals is significantly improved, and by reducing the participation of the macro-motion fast-reflection mirror when the error is low, the impact of macro-motion measurement noise on the overall system accuracy is effectively suppressed. Attached Figure Description

[0094] Figure 1 This is a schematic diagram of the structure of the large stroke, high bandwidth, precision composite axis beam scanning device of the present invention;

[0095] Figure 2 yes Figure 1 A schematic diagram of beam deflection during operation;

[0096] Figure 3 These are the system response test results of this invention under a large stroke of 300Hz;

[0097] Figure 4 These are the system response test results of this invention under a short stroke of 300Hz.

[0098] Markings: 1-Laser; 2-Micro-motion fast-reflection mirror; 3-Macro-motion fast-reflection mirror; 4-PSD position sensor; 21-Micro-motion mirror bracket; 22-Micro-motion mirror; 23-Micro-motion mirror driver; 24-Micro-motion mirror sensor; 31-Macro-motion mirror bracket; 32-Macro-motion mirror; 33-Macro-motion mirror driver; 34-Macro-motion mirror sensor. Detailed Implementation

[0099] Specific implementation method one: Combining Figure 1 and Figure 2 This embodiment describes a large-stroke, high-bandwidth, precision composite axis beam scanning device, which includes a laser 1, a micro-motion fast-reflection mirror 2, a macro-motion fast-reflection mirror 3, a PSD position sensor 4, and a controller.

[0100] The micro-motion quick-reflection mirror 2 includes a micro-motion mirror 22, a micro-motion mirror support 21, a micro-motion mirror driver 23, and a micro-motion mirror sensor 24. The micro-motion mirror 22 is rotatably connected to the micro-motion mirror support 21. The micro-motion mirror driver 23 is connected to the micro-motion mirror 22 and is used to drive the micro-motion mirror 22 to deflect around the horizontal and vertical axes. The micro-motion mirror sensor 24 is used to measure the horizontal deflection angle of the micro-motion mirror surface of the micro-motion mirror 22. Vertical deflection angle of the micro-moving mirror 22 .

[0101] The micromirror driver 23 includes a micromirror control electrical signal amplification circuit, a micromirror PI controller, and a micromirror driving mechanism. The micromirror driving mechanism consists of three sets of circumferentially equidistant piezoelectric ceramics, which drive the micromirror 22 to rotate. The micromirror sensor 24 consists of three sets of circumferentially equidistant capacitive angle sensors. The micro-motion fast-reflection mirror 2 can achieve high-speed and high-precision adjustment of the beam within a small range, with a high bandwidth; its structure is existing technology.

[0102] The macro-motion fast-reflection mirror 3 includes a macro-motion mirror 32, a macro-motion mirror support 31, a macro-motion mirror driver 33, and a macro-motion mirror sensor 34. The macro-motion mirror 32 is rotatably connected to the macro-motion mirror support 31. The macro-motion mirror driver 33 is connected to the macro-motion mirror 32 and is used to drive the macro-motion mirror 32 to deflect around the horizontal and vertical axes. The macro-motion mirror sensor 34 is used to measure the horizontal deflection angle of the macro-motion mirror surface of the macro-motion mirror 32. Macro-motion mirror 32 vertical deflection angle .

[0103] The macro-motion mirror driver 33 includes a macro-motion mirror control electrical signal amplification circuit, a macro-motion mirror PI controller, and a macro-motion mirror drive mechanism. The macro-motion mirror drive mechanism consists of three sets of circumferentially equidistant magnetoresistive actuators, which drive the macro-motion mirror 32 to rotate. The macro-motion mirror sensor 34 is an eddy current sensor. The macro-motion fast-reflection mirror 3 can achieve adjustment over a large range of beam distances and has a large stroke; its structure is existing technology.

[0104] Laser 1, micro-motion fast reflector 2, macro-motion fast reflector 3, and PSD position sensor 4 are arranged in sequence at intervals so that the laser beam emitted by laser 1 illuminates the center of the mirror surface of micro-motion mirror 22, and after reflecting a first reflected beam, it illuminates the center of the mirror surface of macro-motion mirror 32, and after reflecting a second reflected beam, it illuminates the receiving plane of PSD position sensor 4 perpendicularly.

[0105] The controller includes a frequency domain command signal allocation module, a low-frequency feedforward command module, a deflection command drive module, a beam point position sensing estimation module, and a high-frequency feedback error allocation module.

[0106] The frequency domain command signal distribution module is used to distribute the preset two-dimensional coordinate command signal of the beam point position on the receiving plane of the input PSD position sensor 4. , The low-frequency command signal is assigned as a two-dimensional coordinate system based on the preset beam point position according to the frequency components. , and the high-frequency command signal of the two-dimensional coordinates of the preset beam point position , .

[0107] Soon Decomposed into and ,Will Decomposed into and Specifically:

[0108] ;

[0109] .

[0110] The low-frequency feedforward command module is used to transmit the preset beam point position coordinates low-frequency command signal according to the principle of stroke allocation based on the inverse kinematics principle of the two-stage optical path. , The horizontal deflection angle is preset by converting inverse kinematics into a micromirror feedforward command. Preset vertical deflection angle for micromirror feedforward command Preset horizontal deflection angle for macro-mirror feedforward command Macro-mirror feedforward command preset vertical deflection angle The specific method is to use formulas (14) and (15) for calculation.

[0111] The deflection instruction driver module is used to determine the deflection instruction based on the instructions provided. and The micromirror actuator 23 controls the micromirror 22 to deflect accordingly around the vertical and horizontal axes, and according to... and The macro mirror driver 33 controls the macro mirror 32 to deflect accordingly around the vertical and horizontal axes.

[0112] The beam point position sensing estimation module is used to... , , , Subtract respectively , , , The horizontal feedforward angle deflection error of the micromirror was obtained. Vertical feedforward angle deflection error of the micromirror Macro-mirror horizontal feedforward angle deflection error Macro-mirror vertical feedforward angle deflection error Then, through forward kinematics calculations, the two-dimensional coordinate change command signal of the preset beam point position on the receiving plane of the PSD position sensor 4 is obtained. , .

[0113] Right now ;

[0114] ;

[0115] ;

[0116] .

[0117] The horizontal feedforward angle deflection error of the micro-moving mirror is used to correct the error. Vertical feedforward angle deflection error of the micromirror Macro-mirror horizontal feedforward angle deflection error Macro-mirror vertical feedforward angle deflection error Then, through forward kinematics calculations, the two-dimensional coordinate change command signal of the preset beam point position on the receiving plane of the PSD position sensor 4 is obtained. , There are two methods for calculation:

[0118] Method 1: Calculate using formulas (1) to (12), specifically... Substituting into formula (1) ,Will Substituting into formula (1) ,Will Substituting into formula (1) ,Will Substituting into formula (1) The formula (12) is used to calculate That is , .

[0119] The second method: use formula (13) for calculation, specifically... Substituting into formula (13) ,Will Substituting into formula (13) ,Will Substituting into formula (13) ,Will Substituting into formula (13) The formula (13) is used to calculate That is , .

[0120] The high-frequency feedback error distribution module is used to adjust the two-dimensional coordinates of the preset beam point position according to the command signal. , The low-frequency horizontal correction deflection angle of the micromirror was calculated. Low-frequency vertical correction deflection angle of the micro-moving mirror Macro-mirror low-frequency horizontal correction deflection angle Macro-motion mirror low-frequency vertical correction deflection angle The specific calculation method is as follows:

[0121] The calculation is performed using formulas (14) and (15), specifically... Substituting into formula (15) ,Will Substituting into formula (15) The original formula (15) calculates That is , That is , That is , That is .

[0122] The beam point position sensing estimation module is used to estimate the position of the beam point based on the beam point position sensing estimation module. , , , The actual two-dimensional coordinates of the preset beam point position on the receiving plane of the PSD position sensor 4 are obtained through forward kinematics calculations. , The specific method is to use formulas (1) to (12) or formula (13) to calculate.

[0123] The high-frequency feedback error allocation module is also used to determine the high-frequency command signal based on the preset two-dimensional coordinates of the beam point position. , and the actual two-dimensional coordinates of the preset beam point position , The high-frequency horizontal correction deflection angle of the micromirror was calculated. High-frequency vertical correction of deflection angle of micro-moving mirror High-frequency horizontal correction deflection angle of macro-motion mirror Macro-motion mirror high-frequency vertical correction deflection angle The specific method is to follow steps 801 to 803 as described below.

[0124] The deflection instruction driver module is also used to... and , and , and , and The horizontal compensation deflection angle of the micromirror is obtained by adding them separately. Vertical compensation deflection angle of the micromirror Horizontal compensation deflection angle of macro mirror Vertical compensation deflection angle of macro mirror The micromirror driver 23 controls the micromirror 22 to deflect around the vertical and horizontal axes by angles, respectively. and And control the macro mirror driver 33 to drive the macro mirror 32 to deflect by angles around the vertical axis and the horizontal axis respectively. and This is to adjust the beam point on the receiving plane of the PSD position sensor 4 to the preset beam point position.

[0125] Right now ;

[0126] ;

[0127] ;

[0128] ;

[0129] The two error compensations are superimposed, and then the micro-mirror 22 and macro-mirror 32 are controlled to rotate to correct the position of the beam point on the PSD position sensor 4, thereby improving the control accuracy.

[0130] The micro-mirror 22 and the macro-mirror 32 are arranged parallel to each other and spaced apart. The incident angle of the laser beam emitted by the laser 1 on the micro-mirror 22 is 45°; the incident angle of the primary reflected beam on the macro-mirror 32 is also 45°. That is, the angle between the incident beam (the laser beam emitted by the laser 1) and the reflected beam (the primary reflected beam) on the micro-mirror 22 is 90°, and the angle between the incident beam (the primary reflected beam) and the reflected beam (the secondary reflected beam) on the macro-mirror 32 is 90°. This arrangement facilitates setup and use.

[0131] The large-stroke, high-bandwidth precision composite axis beam scanning device provided by this invention employs a micro-motion mirror and a macro-motion mirror. The micro-motion mirror has a high bandwidth, while the macro-motion mirror has a large stroke. Simultaneously, it corrects the position of the beam point on the PSD position sensor 4, accurately adjusting the actual beam point to the preset beam point position, achieving high precision.

[0132] This invention designs a macro-micro two-stage composite axis beam scanning system. Through dynamic coordination of macro and micro channels, it comprehensively coordinates the performance indicators such as accuracy, bandwidth, and travel of the fast-reflecting mirror. Compared with the traditional composite axis beam scanning system composed of a turntable / galvanometer + fast-reflecting mirror, it can simultaneously guarantee large travel, high bandwidth, and high accuracy, and has a faster overall response speed and stronger anti-interference capability. It has a compact structure, small size, light weight, and is easy to integrate. The nonlinear coupling effect of beam pointing is smaller, making it easier to correct and control.

[0133] The present invention also provides a control method for the above-mentioned large-stroke, high-bandwidth precision composite axis beam scanning device, which includes the following steps:

[0134] Step 100: The frequency domain command signal distribution module assigns the preset two-dimensional coordinate command signal of the beam point position on the receiving plane of the input PSD position sensor 4. , The low-frequency command signal is assigned as a two-dimensional coordinate system based on the preset beam point position according to the frequency components. , and the high-frequency command signal of the two-dimensional coordinates of the preset beam point position , ;

[0135] Soon Decomposed into and ,Will Decomposed into and Specifically:

[0136] ;

[0137] .

[0138] Specifically, the frequency domain command signal distribution module uses a low-pass filter and a high-pass filter for distribution. In the low-frequency feedback loop, the input signal passes through the low-pass filter. :

[0139] ,

[0140] In a high-frequency feedback loop, the input signal passes through a high-pass filter. :

[0141] ,

[0142] in, The imaginary unit, For the current frequency, This is the cutoff frequency of the low-pass filter. This is the cutoff frequency of the high-pass filter. and The values ​​should be equal, in which case the sum of the two distributed signals equals the original signal at any given time. When they are not equal, the controller still converges, but unwanted spikes may appear at special times.

[0143] Step 200: The low-frequency feedforward command module, based on the inverse kinematics principle of the two-stage optical path and according to the principle of travel allocation, transmits the low-frequency command signal of the two-dimensional coordinates of the preset beam point position. , The horizontal deflection angle is preset by converting inverse kinematics into a micromirror feedforward command. Preset vertical deflection angle for micromirror feedforward command Preset horizontal deflection angle for macro-mirror feedforward command Macro-mirror feedforward command preset vertical deflection angle The specific method involves using formulas (14) and (15) for calculation, which will be discussed in detail later.

[0144] Step 300: The deflection instruction driver module, according to... and The micromirror actuator 23 controls the micromirror 22 to deflect accordingly around the vertical and horizontal axes, and according to... and The macro mirror driver 33 controls the macro mirror 32 to deflect accordingly around the vertical and horizontal axes.

[0145] Step 400: The micromirror sensor 24 measures the horizontal deflection angle of the micromirror surface of the micromirror 22. Vertical deflection angle of the micro-moving mirror surface .

[0146] The macro-mirror sensor 34 measures the horizontal deflection angle of the macro-mirror surface of the macro-mirror 32. Vertical deflection angle of macroscopic mirror surface .

[0147] Step 500: The beam point position sensing estimation module will... , , , Subtract respectively , , , The horizontal feedforward angle deflection error of the micromirror was obtained. Vertical feedforward angle deflection error of the micromirror Macro-mirror horizontal feedforward angle deflection error Macro-mirror vertical feedforward angle deflection error Then, through forward kinematics calculations, the two-dimensional coordinate change command signal of the preset beam point position on the receiving plane of the PSD position sensor 4 is obtained. , .

[0148] Right now ;

[0149] ;

[0150] ;

[0151] .

[0152] The horizontal feedforward angle deflection error of the micro-moving mirror is used to correct the error. Vertical feedforward angle deflection error of the micromirror Macro-mirror horizontal feedforward angle deflection error Macro-mirror vertical feedforward angle deflection error Then, through forward kinematics calculations, the two-dimensional coordinate change command signal of the preset beam point position on the receiving plane of the PSD position sensor 4 is obtained. , There are two methods for calculation:

[0153] Method 1: Calculate using formulas (1) to (12), specifically... Substituting into formula (1) ,Will Substituting into formula (1) ,Will Substituting into formula (1) ,Will Substituting into formula (1) The formula (12) is used to calculate That is , .

[0154] The second method: use formula (13) for calculation, specifically... Substituting into formula (13) ,Will Substituting into formula (13) ,Will Substituting into formula (13) ,Will Substituting into formula (13) The formula (13) is used to calculate That is , .

[0155] Step 600: The high-frequency feedback error allocation module uses the preset two-dimensional coordinate change command signal of the beam point position. , The low-frequency horizontal correction deflection angle of the micromirror was calculated. Low-frequency vertical correction deflection angle of the micro-moving mirror Macro-mirror low-frequency horizontal correction deflection angle Macro-motion mirror low-frequency vertical correction deflection angle The specific calculation method is as follows:

[0156] The calculation is performed using formulas (14) and (15), specifically... Substituting into formula (15) ,Will Substituting into formula (15) The original formula (15) calculates That is , That is , That is , That is .

[0157] Step 700: The beam point position sensing estimation module, based on... , , , The actual two-dimensional coordinates of the beam point position on the receiving plane of PSD position sensor 4 are obtained through forward kinematics calculations. , The specific method is to use formulas (1) to (12) or formula (13) for calculation. This will be discussed in detail later.

[0158] Step 800: The high-frequency feedback error allocation module uses the preset two-dimensional coordinates of the beam point position as the basis for the high-frequency command signal. , and the actual two-dimensional coordinates of the beam point position , The high-frequency horizontal correction deflection angle of the micromirror was calculated. High-frequency vertical correction of deflection angle of micro-moving mirror High-frequency horizontal correction deflection angle of macro-motion mirror Macro-motion mirror high-frequency vertical correction deflection angle The specific method is to use steps 801 to 803 as described below.

[0159] Step 900: The deflection instruction driver module will... and , and , and , and The horizontal compensation deflection angle of the micromirror is obtained by adding them separately. Vertical compensation deflection angle of the micromirror Horizontal compensation deflection angle of macro mirror Vertical compensation deflection angle of macro mirror The micromirror driver 23 controls the micromirror 22 to deflect around the vertical and horizontal axes by angles, respectively. and And control the macro mirror driver 33 to drive the macro mirror 32 to deflect by angles around the vertical axis and the horizontal axis respectively. and Specifically:

[0160] ;

[0161] ;

[0162] ;

[0163] .

[0164] The two error compensations are superimposed, and then the micro-mirror 22 and macro-mirror 32 are controlled to rotate to correct the position of the beam point on the PSD position sensor 4, thereby improving the control accuracy.

[0165] There are two ways to calculate step 700:

[0166] The first method, step 700, specifically involves:

[0167] Step 701: Calculate the mirror normal vector of the micro-moving mirror 22 using formula (1). The mirror normal vector of the macro-motion mirror 32 is calculated using formula (2). :

[0168] Formula (1) ;

[0169] Formula (2) ;

[0170] Step 702: Calculate the mirror normal vector of the micro-moving mirror 22 using formulas (3) and (4). In the preset basic coordinate system coordinates in The mirror normal vector of the macro-motion mirror 32 is calculated using formulas (5) and (6). In the preset basic coordinate system coordinates in :

[0171] Formula (3) ;

[0172] Formula (4) ,

[0173] in, Basic coordinate system To the 22 coordinate system of the micro-moving mirror The homogeneous coordinate transformation matrix;

[0174] Formula (5) ;

[0175] Formula (6) ,

[0176] in, Basic coordinate system To the macro-mirror 32 coordinate system The homogeneous coordinate transformation matrix, For the micro-moving mirror coordinate system The origin of the coordinate system and the coordinate system of the macro mirror The distance between the origin of the coordinate system;

[0177] Step 703: Based on the incident beam Calculate the first reflected beam after reflection by micromirror 22 :

[0178] Incident beam The laser beam emitted by laser 1;

[0179] Representing a beam of light in three-dimensional space using the point-direction method, the incident beam... ;

[0180] The first reflected beam is calculated using formulas (7) and (8). ;

[0181] in, and represents the directions of the incident beam and the first reflected beam, respectively, and is a unit-length vector; and These are any points on the incident beam and the first reflected beam, respectively.

[0182] Formula (7) ,

[0183] in, The Householder matrix represents the directional reflection transformation of the micro-mirror 22. It is the identity matrix;

[0184] Formula (8) ,

[0185] in, For the micro-moving mirror coordinate system From the origin of the coordinate system to the base coordinate system The distance from the origin of the coordinate system. It is the identity matrix. It is a zero vector; The mirror reflection matrix of the micro-moving mirror 22;

[0186] Step 704: Based on the first reflected beam The secondary reflected beam after reflection by macro-mirror 32 is calculated using formulas (9) and (10) as follows: , The direction of the secondary reflected beam is given by , and is a vector per unit length. Let be any point on the secondary reflected beam;

[0187] Formula (9) ,

[0188] in, Here is the Householder matrix for the directional reflection transformation of the macro-mirror 32. It is the identity matrix;

[0189] Formula (10) ,

[0190] in, For the macro mirror coordinate system From the origin of the coordinate system to the base coordinate system The distance from the origin of the coordinate system. The mirror reflection matrix of macro-motion mirror 32;

[0191] Step 705: Calculate the secondary reflected beam using formula (11) The actual beam point on the PSD position sensor 4 is in the base coordinate system. Three-dimensional coordinates on :

[0192] Formula (11) ,

[0193] in, This is the normal vector of the receiving plane of the PSD position sensor 4; , , The actual beam point in the base coordinate system X-axis, Y-axis, and Z-axis coordinates;

[0194] Step 706: Use formula (12) to obtain the three-dimensional coordinates of the actual beam point. Converted into two-dimensional coordinates on the receiving plane of PSD position sensor 4. :

[0195] Formula (12) ,

[0196] in, For the micro-moving mirror coordinate system The distance from the origin of the coordinate system to the receiving plane of the PSD position sensor 4.

[0197] The second method, step 700, specifically involves:

[0198] The actual two-dimensional coordinates of the beam point position on the PSD position sensor 4 are calculated using formula (13). Formula (13) is:

[0199] .

[0200] Since the system input angle is small, it can be linearized. Analysis shows that it has good accuracy within the stroke range. After linearization, the two-dimensional coordinates of the actual beam point on the PSD position sensor 4 can be directly calculated using formula (13), simplifying the calculation process. Formula (13) is the linearized calculation formula.

[0201] Specifically, step 800 is as follows:

[0202] The beam displacement on the receiving plane of the PSD position sensor 4 caused by the micromirror 22 reaching its maximum stroke is: , . , It is a constant and a positive value.

[0203] Step 801: Calculate the total horizontal error of the beam point on the receiving plane of the PSD position sensor 4 along the X-axis. and the total vertical error on the Y-axis Specifically:

[0204] ;

[0205] ;

[0206] Step 802: Calculate the total horizontal error. and total vertical error The micro-motion mirror 22 and the macro-motion mirror 32 are assigned, and the horizontal error of the micro-motion mirror is calculated. Horizontal error of macro mirror Vertical error of the micromirror Vertical error of macro mirror Specifically:

[0207] when hour, , ;

[0208] when hour, , ;

[0209] when hour, , ;

[0210] when hour, , ;

[0211] when hour, , ;

[0212] when hour, , ;

[0213] The allocation is based on the following principle: when the error signal is greater than the set adjustable range of the micro-motion quick-reflection mirror 2, the micro-motion mirror 22 outputs its maximum stroke, and the remaining error signal is handled by the macro-motion mirror 32. When the error signal is within the adjustable range of the micro-motion quick-reflection mirror 2, the error signal is entirely handled by the micro-motion mirror 22, and the macro-motion mirror 32 does not handle the error.

[0214] Step 803: Calculate the high-frequency horizontal correction deflection angle of the micromirror. High-frequency vertical correction of deflection angle of micro-moving mirror High-frequency horizontal correction deflection angle of macro-motion mirror Macro-motion mirror high-frequency vertical correction deflection angle Specifically:

[0215] The micromirror PI controller controls the horizontal error of the micromirror. Vertical error of the micromirror Converted to micromirror horizontal compensation output Vertical compensation output of micromirror Then, the high-frequency horizontal correction deflection angle of the micromirror is obtained through inverse kinematics calculation. High-frequency vertical correction of deflection angle of micro-moving mirror The principle of inverse kinematics here is similar to that of formulas (14) and (15). The difference is that formulas (14) and (15) directly calculate four deflection angles using coordinates, while here two deflection angles are calculated using coordinates. Calculating two deflection angles using coordinates is a mature calculation method for inverse kinematics, and will not be elaborated here.

[0216] The macro-mirror PI controller controls the macro-mirror's horizontal error. Vertical error of macro mirror Convert to macro mirror horizontal compensation output Macro-mirror vertical compensation output Then, the high-frequency horizontal correction deflection angle of the macromirror is calculated through inverse kinematics. Macro-motion mirror high-frequency vertical correction deflection angle The principle of inverse kinematics here is similar to that of formulas (14) and (15). The difference is that formulas (14) and (15) directly calculate four deflection angles using coordinates, while here two deflection angles are calculated using coordinates. Calculating two deflection angles using coordinates is a mature calculation method for inverse kinematics, and will not be elaborated here.

[0217] This invention designs a dual-butterfly PI controller (a micro-motion mirror PI controller and a macro-motion mirror PI controller). Due to the significant differences in the dynamic characteristics of the micro- and macro-motion fast-reflecting mirrors, a high-frequency feedback error distribution module is designed to distribute the error. A butterfly distribution mechanism is used to redistribute the horizontal and vertical error signals according to the micro-motion and macro-motion stages. Considering the system's geometric kinematics, the compensator output signal needs to be fed into the fast-reflecting mirror input with the correct direction and gain. A reduced-order generalized inverse kinematics is designed, and the result is butterfly-distributed into the inverse kinematics.

[0218] Specifically, step 200 is as follows:

[0219] Calculate using formulas (14) and (15) , , , ;

[0220] Formula (14) ,

[0221] in, For the travel of the micro-motion quick-reflection mirror 2, For the travel of the Macrotronic Quick Response Mirror 3, These are the inverse kinematic equations.

[0222] Formula (15) ,

[0223] in, , The low-frequency command signal is the two-dimensional coordinate of the preset beam point position.

[0224] The detailed control steps are as follows:

[0225] 1. The frequency domain command signal distribution module will assign the preset two-dimensional coordinate command signal of the beam point position. , Assigned as a low-frequency command signal with two-dimensional coordinates of the preset beam point position. , and the high-frequency command signal of the two-dimensional coordinates of the preset beam point position , .

[0226] 2. The low-frequency feedforward command module uses formulas (14) and (15) to convert the two-dimensional coordinates of the preset beam point position into low-frequency command signals. , Convert to micromirror feedforward command with preset horizontal deflection angle Preset vertical deflection angle for micromirror feedforward command Preset horizontal deflection angle for macro-mirror feedforward command Macro-mirror feedforward command preset vertical deflection angle .

[0227] 3. The deflection instruction driver module is based on and The micromirror actuator 23 controls the micromirror 22 to deflect accordingly around the vertical and horizontal axes, and according to... and The macro mirror driver 33 controls the macro mirror 32 to deflect accordingly around the vertical and horizontal axes.

[0228] 4. The micromirror sensor 24 measures the horizontal deflection angle of the micromirror surface of the micromirror 22. Vertical deflection angle of the micro-moving mirror surface .

[0229] The macro-mirror sensor 34 measures the horizontal deflection angle of the macro-mirror surface of the macro-mirror 32. Vertical deflection angle of macroscopic mirror surface .

[0230] 5. The beam point position sensing estimation module calculates the preset two-dimensional coordinate change command signal of the beam point position on the receiving plane of the PSD position sensor 4. , .

[0231] 6. The low-frequency feedback error compensation module uses a preset two-dimensional coordinate change command signal for the beam point position. , Calculate the low-frequency horizontal correction deflection angle of the micromirror. Low-frequency vertical correction deflection angle of the micro-moving mirror Macro-mirror low-frequency horizontal correction deflection angle Macro-motion mirror low-frequency vertical correction deflection angle .

[0232] 7. The beam point position sensing estimation module estimates based on... , , , The actual two-dimensional coordinates of the beam point position on the receiving plane of the PSD position sensor 4 can be calculated using formulas (1) to (12) or formula (13). , .

[0233] 8. The high-frequency feedback error distribution module uses a preset two-dimensional coordinate high-frequency command signal for the beam point position. , and the actual two-dimensional coordinates of the beam point position , The high-frequency horizontal correction deflection angle of the micromirror was calculated. High-frequency vertical correction of deflection angle of micro-moving mirror High-frequency horizontal correction deflection angle of macro-motion mirror Macro-motion mirror high-frequency vertical correction deflection angle .

[0234] 9. The deflection instruction driver module will and , and , and , and The horizontal compensation deflection angle of the micromirror is obtained by adding them separately. Vertical compensation deflection angle of the micromirror Horizontal compensation deflection angle of macro mirror Vertical compensation deflection angle of macro mirror The micromirror driver 23 controls the micromirror 22 to deflect around the vertical and horizontal axes by angles, respectively. and And control the macro mirror driver 33 to drive the macro mirror 32 to deflect by angles around the vertical axis and the horizontal axis respectively. and This is to adjust the beam point on the receiving plane of the PSD position sensor 4 to the preset beam point position.

[0235] In practical applications, when the feedforward loop signal is set to 0, the feedforward loop performs the above method; when the feedback loop signal is set to 0, the feedback loop performs the above method in the same way.

[0236] The control method for a large-stroke, high-bandwidth precision composite axis beam scanning device provided by this invention comprehensively coordinates the performance indicators such as accuracy, bandwidth, and stroke of the fast-reflecting mirror through dynamic coordination of macro and micro channels. Compared with the traditional composite axis beam scanning system composed of a turntable / galvanometer + fast-reflecting mirror, it can simultaneously ensure large stroke, high bandwidth, and high precision, and has a faster overall response speed and stronger anti-interference capability. The nonlinear coupling effect of beam pointing is smaller, making it easier to correct and control.

[0237] This invention achieves adaptive control of large stroke and high bandwidth through dynamic coordination of macro and micro channels. Within the micro-motion range, the system bandwidth approaches 2500Hz, while maintaining a macro-motion mirror coverage of approximately 500Hz within the large stroke range.

[0238] Figure 3 These are the system response test results of this invention under a large stroke of 300Hz. Figure 4 These are the system response test results of this invention at a short stroke of 300Hz. That is, both are at 300Hz. Figure 3 The amplitude of the rectangular wave reference signal is 10mm. Figure 4 The amplitude of the rectangular wave reference signal is 1 mm. Under a small range of command signals, the system bandwidth is determined by the bandwidth of the micro-motion fast-return mirror. From Figure 3 and Figure 4 As can be seen from this, the present invention can achieve high-precision displacement control.

[0239] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent substitutions, and improvements made to the above embodiments without departing from the scope of the present invention, based on the technical essence of the present invention, and within the spirit and principles of the present invention, shall still fall within the protection scope of the present invention.

Claims

1. A large-stroke, high-bandwidth precision composite axis beam scanning device, characterized in that, Includes laser, micro-motion fast-reflecting mirror, macro-motion fast-reflecting mirror, PSD position sensor, and controller; The micro-motion fast-reflection mirror includes a micro-motion mirror, a micro-motion mirror support, a micro-motion mirror driver, and a micro-motion mirror sensor; The micromirror is rotatably connected to the micromirror support; the micromirror driver is connected to the micromirror and is used to drive the micromirror to deflect around the horizontal and vertical axes; The micromirror sensor is used to measure the horizontal deflection angle of the micromirror surface. Vertical deflection angle of the micro-moving mirror surface ; The macro-motion fast-reflection mirror includes a macro-motion mirror, a macro-motion mirror bracket, a macro-motion mirror driver, and a macro-motion mirror sensor; The macro-motion mirror is rotatably connected to the macro-motion mirror bracket; the macro-motion mirror driver is connected to the macro-motion mirror and is used to drive the macro-motion mirror to deflect around the horizontal axis and the vertical axis; The macro-motion mirror sensor is used to measure the horizontal deflection angle of the macro-motion mirror surface. Vertical deflection angle of macroscopic mirror surface ; The laser, the micro-motion fast-reflecting mirror, the macro-motion fast-reflecting mirror, and the PSD position sensor are arranged in sequence at intervals, so that the laser beam emitted by the laser irradiates the center of the mirror surface of the micro-motion mirror, and after reflecting a first reflected beam, it irradiates the center of the mirror surface of the macro-motion mirror, and after reflecting a second reflected beam, it irradiates the receiving plane of the PSD position sensor perpendicularly. The controller includes a frequency domain command signal allocation module, a low-frequency feedforward command module, a deflection command driving module, a beam point position sensing estimation module, and a high-frequency feedback error allocation module. The frequency domain command signal allocation module is used to assign the preset two-dimensional coordinate command signal of the beam point position on the receiving plane of the PSD position sensor to the input signal. , The low-frequency command signal is assigned as a two-dimensional coordinate system based on the preset beam point position according to the frequency components. , and the high-frequency command signal of the two-dimensional coordinates of the preset beam point position , ; The low-frequency feedforward command module is used to transmit the preset beam point position coordinates low-frequency command signal according to the principle of stroke allocation, based on the inverse kinematics principle of the two-stage optical path. , The horizontal deflection angle is preset by converting inverse kinematics into a micromirror feedforward command. Preset vertical deflection angle for micromirror feedforward command Preset horizontal deflection angle for macro-mirror feedforward command Macro-mirror feedforward command preset vertical deflection angle ; The deflection command driving module is used to... and The micromirror driver is controlled to drive the micromirror to deflect accordingly around the vertical and horizontal axes, and according to... and The macro mirror driver is controlled to drive the macro mirror to deflect accordingly around the vertical and horizontal axes; The beam point position sensing and estimation module is used to... , , , Subtract respectively , , , The horizontal feedforward angle deflection error of the micromirror was obtained. Vertical feedforward angle deflection error of the micromirror Macro-mirror horizontal feedforward angle deflection error Macro-mirror vertical feedforward angle deflection error Then, the two-dimensional coordinate change command signal of the preset beam point position on the receiving plane of the PSD position sensor is obtained through forward kinematics calculation. , ; The high-frequency feedback error allocation module is used to adjust the preset two-dimensional coordinate change command signal of the beam point position. , The low-frequency horizontal correction deflection angle of the micromirror was calculated. Low-frequency vertical correction deflection angle of the micro-moving mirror Macro-mirror low-frequency horizontal correction deflection angle Macro-motion mirror low-frequency vertical correction deflection angle ; The beam point position sensing and estimation module is used to estimate based on , , , The actual two-dimensional coordinates of the preset beam point position on the receiving plane of the PSD position sensor are obtained through forward kinematics calculations. , ; The high-frequency feedback error allocation module is also used to determine the high-frequency command signal based on the preset two-dimensional coordinates of the beam point position. , and the actual two-dimensional coordinates of the preset beam point position , The high-frequency horizontal correction deflection angle of the micromirror was calculated. High-frequency vertical correction of deflection angle of micro-moving mirror High-frequency horizontal correction deflection angle of macro-motion mirror Macro-motion mirror high-frequency vertical correction deflection angle ; The deflection command driving module is also used to... and , and , and , and The horizontal compensation deflection angle of the micromirror is obtained by adding them separately. Vertical compensation deflection angle of the micromirror Horizontal compensation deflection angle of macro mirror Vertical compensation deflection angle of macro mirror The micromirror driver is controlled to drive the micromirror to deflect around the vertical and horizontal axes by angles respectively. and And control the macro mirror driver to drive the macro mirror to deflect around the vertical axis and horizontal axis by angles respectively. and This is to adjust the beam point on the receiving plane of the PSD position sensor to a preset beam point position.

2. The apparatus according to claim 1, characterized in that, The micro-motion mirror and the macro-motion mirror are arranged parallel to each other and spaced apart; the laser beam emitted by the laser has an incident angle of 45° on the micro-motion mirror; the primary reflected beam has an incident angle of 45° on the macro-motion mirror.

3. A control method for the large-stroke, high-bandwidth, precision composite axis beam scanning device as described in claim 1 or 2, characterized in that, Includes the following steps: Step 100: The frequency domain command signal allocation module will input the preset two-dimensional coordinate command signal of the beam point position on the receiving plane of the PSD position sensor. , The low-frequency command signal is assigned as a two-dimensional coordinate system based on the preset beam point position according to the frequency components. , and the high-frequency command signal of the two-dimensional coordinates of the preset beam point position , ; Step 200: The low-frequency feedforward command module, through the inverse kinematics principle of the two-stage optical path and according to the principle of travel allocation, transmits the low-frequency command signal of the two-dimensional coordinates of the preset beam point position. , The horizontal deflection angle is preset by converting inverse kinematics into a micromirror feedforward command. Preset vertical deflection angle for micromirror feedforward command Preset horizontal deflection angle for macro-mirror feedforward command Macro-mirror feedforward command preset vertical deflection angle ; Step 300: The deflection command driving module according to and The micromirror driver is controlled to drive the micromirror to deflect accordingly around the vertical and horizontal axes, and according to... and The macro mirror driver is controlled to drive the macro mirror to deflect accordingly around the vertical and horizontal axes; Step 400: The micromirror sensor measures the horizontal deflection angle of the micromirror surface. Vertical deflection angle of the micro-moving mirror surface ; The macro-motion mirror sensor measures the horizontal deflection angle of the macro-motion mirror surface. Vertical deflection angle of macroscopic mirror surface ; Step 500: The beam point position sensing and estimation module will... , , , Subtract respectively , , , The horizontal feedforward angle deflection error of the micromirror was obtained. Vertical feedforward angle deflection error of the micromirror Macro-mirror horizontal feedforward angle deflection error Macro-mirror vertical feedforward angle deflection error Then, the two-dimensional coordinate change command signal of the preset beam point position on the receiving plane of the PSD position sensor is obtained through forward kinematics calculation. , ; Step 600: The high-frequency feedback error allocation module uses a preset two-dimensional coordinate change command signal for the beam point position. , The low-frequency horizontal correction deflection angle of the micromirror was calculated. Low-frequency vertical correction deflection angle of the micro-moving mirror Macro-mirror low-frequency horizontal correction deflection angle Macro-motion mirror low-frequency vertical correction deflection angle ; Step 700: The beam point position sensing estimation module, based on... , , , The actual two-dimensional coordinates of the beam point position on the receiving plane of the PSD position sensor are obtained through forward kinematics calculations. , ; Step 800: The high-frequency feedback error allocation module uses a preset high-frequency command signal based on the two-dimensional coordinates of the beam point position. , and the actual two-dimensional coordinates of the beam point position , The high-frequency horizontal correction deflection angle of the micromirror was calculated. High-frequency vertical correction of deflection angle of micro-moving mirror High-frequency horizontal correction deflection angle of macro-motion mirror Macro-motion mirror high-frequency vertical correction deflection angle ; Step 900: The deflection command driving module will... and , and , and , and The horizontal compensation deflection angle of the micromirror is obtained by adding them separately. Vertical compensation deflection angle of the micromirror Horizontal compensation deflection angle of macro mirror Vertical compensation deflection angle of macro mirror The micromirror driver is controlled to drive the micromirror to deflect around the vertical and horizontal axes by angles respectively. and And control the macro mirror driver to drive the macro mirror to deflect around the vertical axis and horizontal axis by angles respectively. and This is to adjust the beam point on the receiving plane of the PSD position sensor to a preset beam point position.

4. The method according to claim 3, characterized in that, Step 700 specifically involves: Step 701: Calculate the mirror normal vector of the micro-moving mirror using formula (1). The mirror normal vector of the macro-motion mirror is calculated using formula (2). : Official (1) ; Official (2) ; Step 702: Calculate the mirror normal vector of the micro-moving mirror using formulas (3) and (4). In the preset basic coordinate system coordinates in The mirror normal vector of the macro-motion mirror is calculated using formulas (5) and (6). In the preset basic coordinate system coordinates in : Official (3) ; Official (4) , in, Basic coordinate system To the micro-mirror coordinate system The homogeneous coordinate transformation matrix; Official (5) ; Official (6) , in, Basic coordinate system To the macro mirror coordinate system The homogeneous coordinate transformation matrix, For the micro-moving mirror coordinate system The origin of the coordinate system and the coordinate system of the macro mirror The distance between the origin of the coordinate system; Step 703: Based on the incident beam Calculate the first reflected beam after reflection by the micro-moving mirror. : Incident beam The laser beam emitted by the laser; Representing a beam of light in three-dimensional space using the point-direction method, the incident beam... ; The first reflected beam is calculated using formulas (7) and (8). ; in and represents the directions of the incident beam and the first reflected beam, respectively, and is a unit-length vector; and These are any points on the incident beam and the first reflected beam, respectively. Official (7) , in, The Householder matrix represents the direction reflection transformation of the micro-mirror. It is the identity matrix; Official (8) , in, For the micro-moving mirror coordinate system From the origin of the coordinate system to the base coordinate system The distance from the origin of the coordinate system. It is the identity matrix. It is a zero vector; Let be the mirror reflection matrix of the micro-moving mirror; Step 704: Based on the first reflected beam The secondary reflected beam after reflection by the macro-motion mirror is calculated using formulas (9) and (10) as follows: , The direction of the secondary reflected beam is given by , and is a vector per unit length. Let be any point on the secondary reflected beam; Official (9) , in, Let be the Householder matrix for the directional reflection transformation of the macro-mirror. It is the identity matrix; Official (10) , in, For the macro mirror coordinate system From the origin of the coordinate system to the base coordinate system The distance from the origin of the coordinate system. Let be the mirror reflection matrix of the macro-motion mirror; Step 705: Calculate the secondary reflected beam using formula (11) The actual beam point on the PSD position sensor in the base coordinate system Three-dimensional coordinates on : Official (11) , in, Let be the normal vector of the receiving plane of the PSD position sensor; , , The actual beam point in the base coordinate system X-axis, Y-axis, and Z-axis coordinates; Step 706: Use formula (12) to obtain the three-dimensional coordinates of the actual beam point. Converted into two-dimensional coordinates on the receiving plane of the PSD position sensor. : Official (12) , in, For the micro-moving mirror coordinate system The distance from the origin of the coordinate system to the receiving plane of the PSD position sensor.

5. The method according to claim 4, characterized in that, Step 800 specifically involves: The beam displacement on the receiving plane of the PSD position sensor caused by the micro-moving mirror reaching its maximum stroke is: , ; Step 801: Calculate the total horizontal error of the beam point on the receiving plane of the PSD position sensor along the X-axis. and the total vertical error on the Y-axis Specifically: ； ； Step 802: Calculate the total horizontal error. and total vertical error The micro-motion mirror and the macro-motion mirror are assigned, and the horizontal error of the micro-motion mirror is calculated. Horizontal error of macro mirror Vertical error of the micromirror Vertical error of macro mirror Specifically: when hour, , ; when hour, , ; when hour, , ; when hour, , ; when hour, , ; when hour, , ; Step 803: Calculate the high-frequency horizontal correction deflection angle of the micromirror. High-frequency vertical correction of deflection angle of micro-moving mirror High-frequency horizontal correction deflection angle of macro-motion mirror Macro-motion mirror high-frequency vertical correction deflection angle Specifically: The micromirror PI controller controls the horizontal error of the micromirror. Vertical error of the micromirror Converted to micromirror horizontal compensation output Vertical compensation output of micromirror Then, the high-frequency horizontal correction deflection angle of the micromirror is obtained through inverse kinematics calculation. High-frequency vertical correction of deflection angle of micro-moving mirror ; The macro-mirror PI controller controls the macro-mirror's horizontal error. Vertical error of macro mirror Convert to macro mirror horizontal compensation output Macro-mirror vertical compensation output Then, the high-frequency horizontal correction deflection angle of the macromirror is calculated through inverse kinematics. Macro-motion mirror high-frequency vertical correction deflection angle .

6. The method according to claim 5, characterized in that, Step 200 specifically involves: Calculate using formulas (14) and (15) , , , ; Official (14) , in, The stroke of the micro-motion fast-reflection mirror is... The stroke of the macro-motion fast-reflection mirror, The inverse kinematic equations; Official (15) , in, , The low-frequency command signal is the two-dimensional coordinate of the preset beam point position.

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