An Automatic Positioning and Sample Transfer Method for Sample Stage Based on Visual Feedback

Abstract

This invention discloses an automatic positioning and analysis chamber for a sample stage based on visual feedback, and a sample transfer method. The mechanical structure includes an upper chamber, a lower chamber, and a first connecting chamber connecting the upper and lower chambers and equipped with a gate valve; a composite motion device integrating X, Y, and Z axis displacement stages and a polar angle rotation device is installed at the upper end of the upper chamber through a second connecting chamber; the lower chamber sidewall is connected to the analyzer. Addressing the depth information loss problem inherent in monocular vision, this system employs a binocular vision system to determine the three-dimensional spatial coordinates (X, Y, Z) of the visual marks on the sample stage, fundamentally solving the depth ambiguity and providing a core guarantee for achieving micron-level positioning. The processing module pre-stores standard positioning coordinates and integrates image acquisition, information processing, and position control functions. It achieves micron-level positioning accuracy, intelligent safety assurance, real-time thermal deformation compensation, and full-process automation.

Description

Technical Field

[0001] This invention belongs to the technical field of synchrotron radiation experimental equipment, and in particular relates to an automatic positioning and analysis cavity of the sample stage and a sample transfer method based on visual feedback. Background Technology

[0002] Angle-resolved photoelectron spectroscopy (ARPES), utilizing synchrotron radiation sources with their high brightness, high collimation, and tunable polarization, has become a super "microscope" for revealing the microscopic structure and dynamic processes of matter, and is widely used in materials science, physics, chemistry, and biology. Its high-resolution imaging, surface analysis, and spectroscopic measurements place stringent requirements on the sample environment: they typically need to be conducted under vacuum or ultra-high vacuum to eliminate interference from gas molecules on the sample surface and signals (such as photoelectrons), ensuring measurement accuracy.

[0003] The angle-resolved photoelectron spectroscopy (ARPES) experimental setup mainly includes: a sample inlet chamber for placing the sample holder from the atmosphere and initially evacuating it to a high vacuum; a vacuum transfer chamber connecting the sample inlet chamber and the analysis chamber, serving as a transfer station for sample holder transfer; and the analysis chamber, the ultra-high vacuum main experimental chamber for ARPES measurements. Other components include a sample processing chamber, a spin detector, and an energy analyzer.

[0004] The analytical chamber, as one of the core components of the experimental station, contains an upper and lower chamber. The sample stage is responsible for carrying, transferring, and precisely positioning the sample in a vacuum environment. Its performance directly affects experimental safety and data quality. Taking the ARPES experiment as an example, the spot size of the fourth-generation synchrotron radiation device can reach 3-5 micrometers, which poses an unprecedented challenge to the positioning accuracy of the sample stage. When the focal deviation between the sample and the detector (hemispherical electron energy analyzer) exceeds this range, the synchrotron radiation illumination area will deviate from the target area, and the signal detected by the detector will show significant attenuation.

[0005] Existing sample stage systems typically employ open-loop or semi-open-loop mechanical drive methods, such as using a stepper motor to drive a micrometer for displacement. These systems mainly suffer from the following technical drawbacks:

[0006] High risk of collision: When transferring samples from one vacuum chamber to another, or when bringing them close to precision instruments such as detectors, the operation relies mainly on visual observation and manual operation by the operator. Due to limited observation angles, blind spots, and potential human negligence, accidents involving mechanical collisions between the sample stage and its accessories and critical equipment such as detectors occur frequently, causing significant equipment damage and experimental interruptions.

[0007] Low positioning accuracy: The repeatability of traditional mechanical structures is usually on the order of 10 micrometers, which is difficult to meet the matching requirements of modern synchrotron radiation micrometer-level light spots, resulting in a decrease in signal acquisition quality;

[0008] Thermal deformation has a significant impact: During temperature-varying experiments (e.g., from 10K to 300K), the sample rod will experience millimeter-level displacement due to thermal expansion and contraction, causing the light spot to deviate from the target measurement area, making it impossible to guarantee positional consistency over long-term measurements. Existing systems lack the ability to compensate for such dynamic drift in real time;

[0009] Low level of automation: The sample transfer and positioning process relies heavily on manual operation and intervention, resulting in low efficiency and poor reliability, making it difficult to meet the needs of high-throughput and high-efficiency modern experiments. Summary of the Invention

[0010] The purpose of this invention is to provide an automatic positioning and analysis chamber method for the sample stage based on visual feedback, which aims to solve the technical problems of low sample stage positioning accuracy, high collision risk, inability to compensate for thermal deformation, and low degree of automation in the prior art.

[0011] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0012] An automatic positioning analysis chamber for a sample stage based on visual feedback, wherein the analysis chamber has an upper chamber and a lower chamber;

[0013] The lower end of the upper cavity is connected to the lower cavity through the first connecting cavity, and a gate valve is provided in the first connecting cavity. The upper end is installed with a compound motion device through the second connecting cavity.

[0014] Lower cavity sidewall connectivity analyzer;

[0015] The output end of the compound motion device is connected to the sample stage via a sample rod, which is used to control the sample stage to make adjustments in multiple degrees of freedom.

[0016] The upper and lower cavities have corresponding optical windows equipped with first and second binocular vision systems, respectively.

[0017] It includes a processing module, which integrates an image acquisition unit, an information processing unit, and a position control unit;

[0018] The image acquisition unit is used to acquire real-time images of visual marks on the sample stage by driving the first and second binocular vision systems;

[0019] The information processing unit is used to preprocess the image and convert the image data into the three-dimensional coordinates and pose of the sample stage based on the principle of binocular stereo vision.

[0020] The position control unit is used to adjust the sample stage with multiple degrees of freedom through a compound motion device.

[0021] Furthermore, the composite motion device includes an X-axis horizontal displacement stage, a Y-axis horizontal displacement stage, a Z-axis vertical displacement stage, and a polar angle rotation device located in the second connecting cavity, each independently equipped with a stepper motor for driving, used for three-dimensional coordinate correction, to ensure that the sample is always at the center of rotation during the rotation process.

[0022] Furthermore, the first binocular vision system includes a first camera and a second camera, used to simultaneously acquire the position information of the sample stage in the upper cavity through the first camera and the second camera; the second binocular vision system includes a third camera and a fourth camera, to jointly calculate the position information of the sample stage in the lower cavity and the three-dimensional spatial position information relative to the analyzer.

[0023] A sample transfer method for automatically positioning the analytical cavity on a sample stage based on visual feedback includes the following steps;

[0024] Step 1: Preset standard positioning coordinates: Based on the ideal positioning positions of the sample stage in the upper and lower cavities, preset standard positioning coordinates are performed using the first and second binocular vision systems; the standard positioning coordinates include the initial positioning coordinates of the sample stage in the upper cavity, the coordinates of the virtual safety channel, and the precise positioning coordinates of the lower cavity;

[0025] Step 2, System Initialization: Monitor the vacuum levels of the upper and lower chambers in real time. When the vacuum level of the upper chamber is better than 8×10... -11 Torr, lower chamber vacuum degree better than 6×10 -11 When torr occurs, the gate valve is opened;

[0026] Step 3, Initial positioning of the upper cavity: The sample stage in the upper cavity is positioned in real time using the first binocular vision system. The real-time positioning coordinates are compared with the pre-stored standard positioning coordinates, and the composite motion device is driven by the position control unit to make corrections to ensure that the sample stage is at the precise sample transfer starting point.

[0027] Step 4, Safe Sample Transfer and Path Planning: After the gate valve is opened, the position control unit controls the sample stage to move along the pre-stored virtual safety channel coordinates. During this process, the first binocular vision system continuously monitors to ensure that the deviation of the motion trajectory is within the safety tolerance. When the sample stage descends to the preset height, the system automatically checks whether its lateral position and angle deviation are within the safety tolerance. If the tolerance is exceeded, the system immediately starts the closed-loop control mechanism to correct the trajectory. The movement can only continue after the pose meets the requirements, ensuring that the sample transfer process is always within the preset virtual safety channel.

[0028] Step 5, Precise positioning in the lower cavity: When the sample stage enters the lower cavity, the system enters the precise positioning and continuous safety monitoring mode. The second binocular vision system performs real-time three-dimensional calibration of the sample stage and compares it with the pre-stored precise positioning coordinates of the lower cavity. The position control unit drives the composite motion device to perform multi-degree-of-freedom precision adjustment until the deviation is less than the precise positioning threshold.

[0029] Step Six: Continuous Collision Prevention Monitoring: The second binocular vision system operates continuously at a set frequency, calculating the spatial distance between the sample stage and the analyzer in real time. This distance data is fed back to the processing module in real time to ensure that it is always maintained above the safe operating distance. When the distance is less than the first safety threshold, the system activates a feedforward control strategy to actively adjust the sample stage's movement trajectory to avoid potential collision risks. When the distance further decreases to the second danger threshold, the system immediately stops all movement and triggers an audible and visual alarm to ensure equipment safety.

[0030] Step 7, High-precision scanning and thermal compensation: After completing single-point precise positioning, the system moves the sample stage according to the preset scanning sequence, repeating the precise positioning process in step 5 at each point to ensure the coordinate accuracy of each data point. The system periodically runs the positioning process to automatically compensate for pose drift caused by thermal deformation.

[0031] Furthermore, using the method of pre-setting standard positioning coordinates and real-time positioning coordinates, the image acquisition unit acquires images of the sample stage through the first and second binocular vision systems, and the information processing unit preprocesses the images and converts the image data into three-dimensional coordinates of the sample stage based on the principle of binocular vision.

[0032] Furthermore, the information processing unit performs preprocessing operations on the image, including noise suppression, contrast enhancement, and lens distortion correction, to generate clear and standardized image frames for subsequent coordinate calculation.

[0033] Furthermore, the first and second binocular vision systems convert image data into three-dimensional coordinates of the sample stage, outputting the two-dimensional pixel coordinates (u1, v1) and (u2, v2) of the feature points in the camera image coordinate system; based on pre-calibrated binocular camera parameters, the three-dimensional spatial coordinates (X, Y, Z) of the feature points in the world coordinate system are reconstructed using triangulation, and its mathematical model is defined by the following set of equations:

[0034] ;

[0035] Where λ1 and λ2 are scale factors, M1 and M2 are camera intrinsic parameter matrices, I represents the identity matrix / identity matrix of the image coordinate system (or image plane), and R and T are the rotation matrix and translation vector of the right camera relative to the left camera, respectively.

[0036] Furthermore, the processing module compares the real-time positioning 3D coordinates with the pre-stored standard positioning coordinates and outputs displacement deviation commands. The displacement deviation commands are obtained through displacement deviation calculation. The calculated real-time positioning 3D coordinates (X,Y,Z) are compared with the pre-stored standard positioning coordinates (X0,Y0,Z0). The linear displacement deviation commands (ΔX, ΔY, ΔZ) for each axis are generated through differential calculation and output to the position control unit. The position control unit receives the displacement deviation commands and uses its built-in motion control card to convert the commands into drive signals for each motor in the composite motion device, thereby realizing automatic and precise correction of the sample stage position.

[0037] The present invention has the following beneficial effects:

[0038] (1) Micrometer-level positioning accuracy: Through the synergy of a high-resolution binocular vision system and a precise closed-loop control algorithm, the spatial pose of the sample stage can be accurately perceived in real time, and automatic compensation and correction can be made according to the deviation. For example, the positioning accuracy in the x / y / z directions is better than ±1μm, and the directional positioning accuracy is better than ±1μm (depending on the specific design), which is several times or even an order of magnitude higher than the accuracy of traditional mechanical positioning methods (usually on the order of ±10μm).

[0039] (2) Vacuum compatible monitoring: Non-contact machine vision technology is used for pose measurement. All vision components can be installed outside the vacuum chamber (observed through the vacuum window), ensuring that the vacuum environment is not disturbed.

[0040] (3) Intelligent safety assurance: The system can monitor the relative distance between the sample stage and surrounding key components (such as detectors) in real time, and has the ability to actively warn and avoid collisions, which fundamentally eliminates the risk of equipment collisions caused by human error and significantly improves experimental safety.

[0041] (4) High degree of automation and efficiency improvement: The system realizes the automated closed loop of "detection-decision-execution" in the sample transfer and positioning process. Users only need to set the target pose, and the system can automatically, quickly and accurately complete the operation, which greatly liberates manpower and improves experimental efficiency.

[0042] (5) Real-time thermal deformation compensation: Continuous visual monitoring can capture and compensate for positional drift caused by temperature changes in real time, ensuring the stability of the sample during long-term, temperature-changing measurement, and guaranteeing the comparability and validity of the data.

[0043] (6) Good applicability and scalability: The design of this system does not depend on the specific structure and form of the sample stage. The core visual feedback and control strategy is universal. By adapting markers and adjusting visual parameters, it can be widely deployed in different types of synchrotron radiation experimental stations or other scientific research equipment that requires precise positioning in a vacuum environment. The vision system has good adaptability to sample sizes and features within a certain range. Attached Figure Description

[0044] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0045] Figure 1 : Schematic diagram of the sample stage located in the upper cavity structure of the present invention.

[0046] Figure 2 : Schematic diagram of the sample stage extending into the lower cavity structure of the present invention.

[0047] The components represented by each number in the attached figure are listed below: upper chamber 8, lower chamber 9, gate valve 15, polar angle rotation device 14, analyzer 10, sample rod 5, sample 6, sample stage 7, X-axis horizontal displacement stage 11, Y-axis horizontal displacement stage 12, Z-axis vertical displacement stage 13, first camera 1, second camera 2, third camera 3, and fourth camera 4. Detailed Implementation

[0048] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0049] like Figure 1 and Figure 2 As shown: A sample stage automatic positioning analysis chamber based on visual feedback, the analysis chamber has an upper chamber 8 and a lower chamber 9; the lower end of the upper chamber 8 is connected to the lower chamber 9 through a first connecting chamber, the first connecting chamber is equipped with a gate valve 15, and the upper end is installed with a compound motion device through a second connecting chamber; the side wall of the lower chamber 9 is connected to the analyzer 10;

[0050] The output end of the composite motion device is connected to the sample stage 7 via the sample rod 5, which is used to control the sample stage 7 to make multi-degree-of-freedom adjustments. The composite motion device includes an X-axis horizontal displacement stage 11, a Y-axis horizontal displacement stage 12, a Z-axis vertical displacement stage 13 and a polar angle rotation device 14 located in the second connecting cavity. Each of them is independently equipped with a stepper motor for driving, which is used for three-dimensional coordinate correction to ensure that the sample is always at the center of rotation during the rotation process.

[0051] The upper cavity 8 and the lower cavity 9 are respectively equipped with the first and second binocular vision systems in the corresponding optical windows. The first binocular vision system includes a first camera 1 and a second camera 2, which are used to synchronously acquire the position information of the sample stage 7 in the upper cavity 8 through the first camera 1 and the second camera 2. The second binocular vision system includes a third camera 3 and a fourth camera 4, which are used to jointly calculate the position information of the sample stage 7 in the lower cavity 9 and the three-dimensional spatial position information relative to the analyzer 10.

[0052] It includes a processing module, whose processing unit is a single-chip microcomputer or microcomputer processor, with integrated memory and arithmetic unit; it integrates an image acquisition unit, an information processing unit and a position control unit;

[0053] The image acquisition unit is used to acquire real-time images of the visual markers on the sample stage 7 by driving the first and second binocular vision systems;

[0054] The information processing unit is used to preprocess the image and convert the image data into the three-dimensional coordinates and pose of the sample stage based on the principle of binocular stereo vision.

[0055] The position control unit is used to adjust the sample stage with multiple degrees of freedom through a compound motion device.

[0056] A sample transfer method for automatically positioning the analytical cavity on a sample stage based on visual feedback includes the following steps;

[0057] Step 1: Preset standard positioning coordinates: Based on the ideal positioning positions of the sample stage 7 in the upper cavity 8 and lower cavity 9, preset standard positioning coordinates are performed using the first and second binocular vision systems; the standard positioning coordinates include the initial positioning coordinates of the upper cavity sample stage 7, the virtual safety channel coordinates, and the precise positioning coordinates of the lower cavity 9;

[0058] Step 2, System Initialization: Monitor the vacuum levels of upper chamber 8 and lower chamber 9 in real time. When the vacuum level of upper chamber 8 is better than 8 × 10⁻⁶, the system will automatically initialize. -11 The vacuum level in the lower chamber (TOR) is better than 6×10⁻⁶. -11 When torr, the gate valve 15 is opened; this dual vacuum protection mechanism ensures that the sample is not contaminated by gas molecules during the transfer process, providing the necessary conditions for precision measurement in an ultra-high vacuum environment.

[0059] Step 3, Initial positioning of the upper cavity: The sample stage 7 in the upper cavity 8 is positioned in real time using the first binocular vision system. The real-time positioning three-dimensional coordinates are compared with the pre-stored standard positioning coordinates, and the composite motion device is driven by the position control unit to make corrections to ensure that the sample stage is at the precise sample transfer starting point.

[0060] Step 4, Safe Sample Transfer and Path Planning: After the gate valve 15 is opened, the position control unit controls the sample stage 7 to move along the pre-stored virtual safety channel coordinates. During this process, the first binocular vision system continuously monitors to ensure that the movement trajectory deviation is within the safety tolerance. When the sample stage 7 descends to the preset height, the system automatically checks whether its lateral position and angle deviation are within the safety tolerance range (position deviation ±2 mm, angle deviation ±0.5°). If the tolerance is exceeded, the system immediately starts the closed-loop control mechanism to correct the trajectory. The movement can only continue after the position and posture meet the requirements, ensuring that the sample transfer process is always within the preset virtual safety channel.

[0061] Step 5, Precise positioning in the lower cavity: When the sample stage 7 enters the lower cavity 9, the system enters the precise positioning and continuous safety monitoring mode. The second binocular vision system performs real-time three-dimensional calibration of the sample stage 7 and compares it with the pre-stored precise positioning coordinates of the lower cavity. The position control unit drives the composite motion device to perform multi-degree-of-freedom precision adjustment until the deviation is less than the precise positioning threshold (translation error threshold > 3μm).

[0062] Step Six: Continuous Collision Prevention Monitoring: The second binocular vision system operates continuously at a set frequency (30Hz) to calculate the spatial distance between the sample stage 7 and the analyzer 10 in real time. This distance data is fed back to the processing module in real time to ensure that it is always maintained above the safe operating distance. When the distance is less than the first safety threshold (30 mm), the system activates the feedforward control strategy to actively adjust the motion trajectory of the sample stage to avoid potential collision risks. When the distance further shrinks to the second danger threshold (15 mm), the system immediately stops all movement and triggers an audible and visual alarm to ensure equipment safety.

[0063] Step 7, High-precision scanning and thermal compensation: After completing single-point precise positioning, the system moves the sample stage according to the preset scanning sequence, repeating the precise positioning process in step 5 at each point to ensure the coordinate accuracy of each data point. The system periodically runs the positioning process to automatically compensate for pose drift caused by thermal deformation.

[0064] Among them, the method of preset standard positioning coordinates and real-time positioning coordinates involves the image acquisition unit acquiring images of the sample stage 7 through the first and second binocular vision systems, and the information processing unit preprocessing the images and converting the image data into three-dimensional coordinates of the sample stage based on the binocular vision principle.

[0065] The information processing unit performs preprocessing operations on the image, including noise suppression, contrast enhancement, and lens distortion correction, to generate clear and standardized image frames for subsequent coordinate calculation.

[0066] The first and second binocular vision systems convert image data into three-dimensional coordinates of the sample stage, outputting the two-dimensional pixel coordinates (u1, v1) and (u2, v2) of the feature points in the camera image coordinate system. Based on pre-calibrated binocular camera parameters, the three-dimensional spatial coordinates (X, Y, Z) of the feature points in the world coordinate system are reconstructed using triangulation. The mathematical model is defined by the following set of equations:

[0067] ;

[0068] Where λ1 and λ2 are scale factors, M1 and M2 are camera intrinsic parameter matrices, I represents the identity matrix / identity matrix of the image coordinate system (or image plane), and R and T are the rotation matrix and translation vector of the right camera relative to the left camera, respectively.

[0069] The processing module compares the real-time positioning 3D coordinates with the pre-stored standard positioning coordinates and outputs displacement deviation commands. The displacement deviation commands are obtained through displacement deviation calculation. The calculated real-time positioning 3D coordinates (X, Y, Z) are compared with the pre-stored standard positioning coordinates (X0, Y0, Z0). The linear displacement deviation commands (ΔX, ΔY, ΔZ) for each axis are generated through differential calculation and output to the position control unit. The position control unit receives the displacement deviation commands and uses its built-in motion control card to convert the commands into drive signals for each motor in the composite motion device, thereby realizing automatic and precise correction of the sample stage position.

[0070] These embodiments are selected and specifically described in this specification in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can better understand and utilize the present invention.

Claims

1. A sample transfer method based on visual feedback automatic positioning of a sample stage in an analysis chamber, characterized in that: the analysis chamber has an upper chamber (8) and a lower chamber (9) inside; the lower end of the upper chamber (8) is connected to the lower chamber (9) through a first communication chamber, the first communication chamber is provided with a gate valve (15), and the upper end is provided with a composite motion device through a second communication chamber; the side wall of the lower chamber (9) is connected to an analyzer (10); the output end of the composite motion device is connected to a sample stage (7) through a sample rod (5) for controlling the sample stage (7) to adjust in multiple degrees of freedom; the upper chamber (8) and the lower chamber (9) are respectively provided with first and second binocular vision systems corresponding to optical windows; it comprises a processing module integrated with an image acquisition unit, an information processing unit and a position control unit; the image acquisition unit is used to acquire real-time images of visual marks of the sample stage (7) by driving the first and second binocular vision systems; the information processing unit is used to pre-process the images and convert the image data into three-dimensional coordinates and poses of the sample stage based on the binocular stereo vision principle; the position control unit is used to adjust the sample stage in multiple degrees of freedom through the composite motion device; it comprises the following steps: step one, preset standard positioning coordinates: according to the ideal positioning position of the sample stage (7) in the upper chamber (8) and the lower chamber (9), the first and second binocular vision systems are used to preset standard positioning coordinates; the standard positioning coordinates include the initial positioning coordinates of the sample stage (7) in the upper chamber, the virtual safety passage coordinates and the precise positioning coordinates of the lower chamber (9); step three, initial positioning of the upper chamber: the first binocular vision system is used to real-time position the three-dimensional coordinates of the sample stage (7) in the upper chamber (8), the real-time positioning three-dimensional coordinates are compared with the pre-stored standard positioning coordinates, and the composite motion device is driven by the position control unit for correction to ensure that the sample stage is at the precise sample transfer starting point; step four, safe sample transfer and path planning: after the gate valve (15) is opened, the position control unit controls the sample stage (7) to move along the pre-stored virtual safety passage coordinates, in this process, the first binocular vision system continuously monitors to ensure that the motion trajectory deviation is within the safety tolerance; when the sample stage (7) is lowered to the preset height, the system automatically checks whether the lateral position and angle deviation are within the safety tolerance range, if the tolerance is exceeded, the system immediately starts the closed-loop control mechanism for trajectory correction, and the position meets the requirements before the movement can continue, ensuring that the sample transfer process is always in the pre-set virtual safety passage; step five, precise positioning of the lower chamber: when the sample stage (7) enters the lower chamber (9), the system enters the precise positioning and continuous safety monitoring mode, the second binocular vision system real-time three-dimensional positioning of the sample stage (7) is carried out, and compared with the pre-stored precise positioning coordinates of the lower chamber, the position control unit drives the composite motion device to adjust in multiple degrees of freedom until the deviation is less than the precise positioning threshold. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Step two, system initialization: real-time monitoring of the vacuum degree of the upper cavity (8) and the lower cavity (9), when the vacuum degree of the upper cavity (8) is better than 8x10 -11 torr, the vacuum degree of the lower cavity (9) is better than 6x10 -11 torr, open the shutter valve (15); ​ ​ ​ Step six, continuous anti-collision monitoring: the second binocular vision system runs continuously at a set frequency, and calculates the spatial distance between the sample stage (7) and the analyzer (10) in real time; the distance data is fed back to the processing module in real time to ensure that it is always maintained above the safe operating distance; when the distance is less than the first safety threshold, the system activates the feedforward control strategy to actively adjust the sample stage motion trajectory to avoid potential collision risks; when the distance is further reduced to the second danger threshold, the system immediately suspends all movements and triggers an audible and visual alarm to ensure equipment safety; Step seven, high-precision scanning and thermal compensation: after completing single-point fine positioning, the system moves the sample stage according to the preset scanning sequence, and repeats the fine positioning process in step five at each point to ensure the coordinate accuracy of each data point. The system periodically runs the positioning process to automatically compensate for the pose drift caused by thermal deformation.

2. The sample transfer method of claim 1, wherein the method further comprises: determining a position of the sample stage based on the visual feedback; and adjusting the position of the sample stage based on the determined position of the sample stage. The composite motion device includes an X-axis horizontal displacement table (11), a Y-axis horizontal displacement table (12), a Z-axis vertical displacement table (13), and a polar angle rotating device (14) in the second communication cavity, and is independently driven by a stepping motor, for three-dimensional coordinate correction, to ensure that the sample is always in the position of the rotation center during rotation.

3. The method of claim 1, wherein the method further comprises: determining a position of the sample stage based on the visual feedback. The first binocular vision system includes a first camera (1) and a second camera (2) for synchronously collecting position information of the sample stage (7) in the upper cavity (8) through the first camera (1) and the second camera (2); the second binocular vision system includes a third camera (3) and a fourth camera (4) for jointly calculating position information of the sample stage (7) in the lower cavity (9) and three-dimensional spatial position information relative to the analyzer (10).

4. The sample transfer method of claim 1, wherein the method further comprises: determining a position of the sample stage based on the visual feedback. The method for presetting standard positioning coordinates and real-time positioning coordinates, the image acquisition unit acquires sample stage (7) images through the first and second binocular vision systems, the information processing unit pre-processes the images, and converts the image data into three-dimensional coordinates of the sample stage based on the binocular vision principle.

5. The sample transfer method of claim 4, wherein the visual feedback based automatic positioning of the sample stage to the analysis chamber comprises: The pre-processing operation performed by the information processing unit on the image includes noise suppression, contrast enhancement, and lens distortion correction to generate clear and standardized image frames for subsequent coordinate calculation. ​ 6. The sample transfer method of claim 5, wherein the method further comprises: determining a position of the sample stage based on the visual feedback. The method for converting image data into three-dimensional coordinates of the sample stage by the first and second binocular vision systems outputs two-dimensional pixel coordinates (u1, v1) and (u2, v2) of the feature points in the camera image coordinate system; based on the pre-calibrated binocular camera parameters, the three-dimensional spatial coordinates (X, Y, Z) of the feature points in the world coordinate system are reconstructed by the triangulation method, and the mathematical model is defined by the following equation set: ； where λ1 and λ2 are scale factors, M1 and M2 are camera intrinsic matrices, I represents the unit matrix / identification matrix of the image coordinate system, and R and T are the rotation matrix and translation vector of the right camera relative to the left camera, respectively.

7. The sample transfer method for automatic positioning of the analysis chamber on a sample stage based on visual feedback according to claim 6, characterized in that: The processing module compares the real-time positioning three-dimensional coordinates with the pre-stored standard positioning coordinates, outputs a displacement deviation instruction, and obtains the displacement deviation instruction through displacement deviation calculation. The real-time positioning three-dimensional coordinates (X, Y, Z) obtained by solving are compared with the pre-stored standard positioning coordinates (X0, Y0, Z0), a linear displacement deviation instruction (ΔX, ΔY, ΔZ) of each axis is generated through difference calculation, and is output to a position control unit. The position control unit receives the displacement deviation instruction, solves the instruction into a driving signal of each motor in the compound motion device through a built-in motion control card, so as to realize automatic and precise correction of the sample table position.

Images