Experimental platform for particle accelerator material irradiation and control method

Abstract

The invention relates to an experimental platform for particle accelerator material irradiation, which comprises a six-dimensional mechanical arm, a camera and light spot identification system, a rotary grasping clamp and an integrated control system, and is characterized in that the camera and light spot identification system is used for acquiring a particle beam light spot image on a scintillator in real time, and transmitting data to the integrated control system; the integrated control system accurately calculates the real-time spatial position deviation of the sample relative to the center of the irradiation beam; then the six-dimensional mechanical arm is driven to dynamically adjust the posture compensation deviation, and meanwhile, the rotary gripper is controlled to stably clamp the sample and rotate by 360 degrees, so that accurate and flexible positioning, uniform irradiation, stable clamping and real-time monitoring and correction of the sample are realized, and the precision, reliability and efficiency of an experiment are improved; and an efficient, stable and intelligent experimental tool is provided for particle accelerator material irradiation research.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of radiotherapy, in particular to an experimental platform for particle accelerator material irradiation and a control method. BACKGROUND

[0002] In the research of particle accelerator material irradiation, the irradiation behavior and performance change of the material are the focus of the research. The irradiation experiment is to expose the material sample to a high-energy particle beam to simulate the material damage process in a nuclear reactor or other irradiation environment, so as to study the microstructure change, mechanical property degradation and radiation resistance performance of the material. However, the current particle accelerator material irradiation experimental device has many deficiencies in sample positioning, irradiation uniformity, sample stability, real-time monitoring capability and experimental efficiency. SUMMARY

[0003] Therefore, it is necessary to provide an experimental platform for particle accelerator material irradiation and a control method to solve the above problems.

[0004] In a first aspect, the present application provides an experimental platform for particle accelerator material irradiation, comprising a six-dimensional mechanical arm, a camera and a light spot recognition system, a rotating gripper and an integrated control system; the integrated control system is connected to the six-dimensional mechanical arm, the camera and the light spot recognition system and the rotating gripper; the camera and the light spot recognition system are fixed at the front end of the six-dimensional mechanical arm; the rotating gripper is fixed at the execution end of the six-dimensional mechanical arm of the six-dimensional mechanical arm;

[0005] The six-dimensional mechanical arm is used to control the position and attitude of the sample;

[0006] The camera and the light spot recognition system are used to capture the particle beam light spot image data on the scintillator in real time, and perform light spot center positioning processing on the particle beam light spot image data to obtain the light spot center position;

[0007] The rotating gripper is used to clamp and drive the sample to rotate 360° around the horizontal axis parallel to the particle beam;

[0008] The integrated control system is used to acquire the data feedback from the six-dimensional mechanical arm, the camera and the light spot recognition system and the rotating gripper, and perform data processing to output control instructions, so that the six-dimensional mechanical arm adjusts the attitude to compensate for the position deviation, the rotating gripper stably clamps and uniformly rotates, so as to ensure that the sample is always in the center of the irradiation beam and is uniformly irradiated.

[0009] In one embodiment, the experimental platform further comprises a level; the level is integrated on the six-dimensional mechanical arm; the integrated control system is connected to the level;

[0010] The level is used to acquire the horizontal state data of the sample;

[0011] An integrated control system is used to send adjustment commands to the six-dimensional robotic arm based on horizontal state data, so that the sample is perpendicular to the horizontal plane.

[0012] In one embodiment, the experimental platform further includes an accelerometer integrated on a six-dimensional robotic arm; an integrated control system controls the accelerometer.

[0013] An accelerometer is used to acquire acceleration data of a six-dimensional robotic arm during its movement.

[0014] An integrated control system is used to adjust the motion state of the robotic arm based on acceleration data to eliminate the impact of vibration on the sample.

[0015] In one embodiment, the aforementioned six-dimensional robotic arm is installed in the target chamber of a particle accelerator and has translational degrees of freedom along the X, Y, and Z axes and rotational degrees of freedom about the X, Y, and Z axes.

[0016] In one embodiment, the scintillator is a 10mm circular hole; the material of the scintillator includes inorganic scintillators such as LYSO:Ce, BGO, NaI:Tl and CsI:Tl, as well as plastic scintillator BC-408.

[0017] Secondly, this application also provides a control method for an experimental platform for material irradiation in a particle accelerator, the method comprising:

[0018] The six-dimensional robotic arm is controlled to adjust the initial state of the sample so that the sample is perpendicular to the horizontal plane.

[0019] The camera and spot recognition system are controlled to capture the particle beam spot image data on the scintillator in real time, and the spot center is located by performing spot center localization processing on the particle beam spot image data to obtain the spot center position.

[0020] Control the rotating gripper to hold and drive the sample to rotate 360° around a horizontal axis parallel to the particle beam;

[0021] Data is acquired from the six-dimensional robotic arm, camera and spot recognition system and rotating gripper, and the data is processed to output control commands. The six-dimensional robotic arm adjusts its posture to compensate for positional deviations, and the rotating gripper stabilizes and rotates at a constant speed to ensure that the sample is always in the center of the irradiation beam and is uniformly irradiated.

[0022] In one embodiment, the above-mentioned spot center localization processing of particle beam spot image data to obtain the spot center position includes:

[0023] Gaussian filtering was applied to the original particle beam spot image data to obtain the denoised spot image data.

[0024] Adopting the adaptive threshold method to binarize and segment the de-noised light spot image data, to obtain the binarized image data containing only the light spot region;

[0025] In the light spot region of the binarized image data, the coordinates and corresponding gray values of all pixels in the light spot region are statistically processed, and the sum of the product of the gray value of each pixel in the region and its own coordinates is calculated, and then divided by the sum of the gray values of all pixels in the region, to obtain the light spot center position; the light spot center position is the coordinate data of the light spot center in the image pixel coordinate system.

[0026] In one embodiment, the above method further comprises:

[0027] Pre-calibration of the camera is performed to obtain the intrinsic matrix of the camera and the extrinsic matrix of the camera relative to the end of the robot arm;

[0028] Based on the pixel coordinate data of the light spot center in the image pixel coordinate system and the intrinsic matrix of the camera, the pixel coordinate data is back-projected to obtain the coordinate data of the light spot center in the image physical coordinate system;

[0029] According to the known fixed distance between the scintillator and the sample, the coordinate data of the light spot center in the image physical coordinate system is mapped to the plane of the six-dimensional robot arm end tool coordinate system to obtain the projection coordinate of the light spot center in the tool coordinate system;

[0030] The projection coordinate of the light spot center in the tool coordinate system is compared with the target coordinate of the preset light spot target in the tool coordinate system, and the difference between the projection coordinate of the light spot center in the tool coordinate system and the preset light spot target in the tool coordinate system is calculated to obtain the spatial position deviation data of the sample relative to the center of the irradiation beam; the spatial position deviation data is used to ensure that the sample is always in the center of the irradiation beam and is uniformly irradiated.

[0031] In one embodiment, the above method further comprises:

[0032] The spatial position deviation data of the sample relative to the center of the irradiation beam is input into the built-in PID controller for motion instruction calculation and processing to obtain the posture adjustment instruction of the six-dimensional robot arm;

[0033] Based on the posture adjustment instruction of the six-dimensional robot arm, the six-dimensional robot arm is driven to move and adjust to correct the spatial position deviation, so as to ensure that the sample is always in the center position of the irradiation beam.

[0034] In a third aspect, the application also provides a control device for an experimental platform for particle accelerator material irradiation, which comprises:

[0035] A state adjustment module is configured to control the six-dimensional robot arm to adjust an initial state of the sample so that the sample is perpendicular to a horizontal plane.

[0036] A position determination module is configured to control the camera and the light spot recognition system to capture particle beam light spot image data on the scintillator in real time and perform light spot center positioning processing on the particle beam light spot image data to obtain a light spot center position.

[0037] A rotating module is configured to control the rotating gripper to hold and drive the sample to rotate 360° around a horizontal axis parallel to the particle beam.

[0038] A robot arm adjustment module is configured to acquire data fed back by the six-dimensional robot arm, the camera and the light spot recognition system, and the rotating gripper, and perform data processing to output a control instruction, so that the six-dimensional robot arm adjusts a posture to compensate for a positional deviation, the rotating gripper stably holds and uniformly rotates, and the sample is always ensured to be at the center of the irradiation beam and uniformly irradiated.

[0039] The experimental platform for particle accelerator material irradiation includes a six-dimensional robot arm, a camera and a light spot recognition system, a rotating gripper, and an integrated control system. The camera and the light spot recognition system acquire particle beam light spot image data on the scintillator in real time and transmit the data to the integrated control system. The integrated control system accurately calculates a real-time spatial positional deviation of the sample relative to the center of the irradiation beam. The six-dimensional robot arm is driven to dynamically adjust a posture to compensate for the deviation, and the rotating gripper is controlled to stably hold the sample and rotate 360°, so as to realize accurate and flexible positioning, uniform irradiation, stable holding, real-time monitoring and correction of the sample, thereby improving the accuracy, reliability and efficiency of the experiment and providing an efficient, stable and intelligent experimental tool for particle accelerator material irradiation research. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 It is a core component assembly relationship diagram of the experimental platform in an embodiment.

[0041] Figure 2 It is a complete schematic diagram of the experimental platform in an embodiment.

[0042] Figure 3 It is a flowchart of a control method of the experimental platform for particle accelerator material irradiation in an embodiment.

[0043] Figure 4 It is a flowchart of light spot center positioning processing in an embodiment.

[0044] Figure 5 It is a flowchart of coordinate conversion and deviation calculation in an embodiment.

[0045] Figure 6 It is a flowchart of robot arm posture adjustment in an embodiment.

[0046] Figure 7 Flowchart of the closed-loop control logic in one embodiment;

[0047] Figure 8 Block diagram of the control device for the experimental platform for particle accelerator material irradiation in one embodiment. DETAILED DESCRIPTION

[0048] In order to make the purposes, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0049] First, before specifically introducing the technical solutions of the embodiments of the present application, the technical background based on which the embodiments of the present application are introduced.

[0050] The existing irradiation experimental device has some limitations in actual application, mainly reflected in the following aspects:

[0051] 1) Insufficient flexibility of sample positioning and adjustment:

[0052] Traditional irradiation experimental devices usually use fixed sample holders or simple mechanical devices to place samples. The adjustment mode of these devices is relatively limited, and usually only simple horizontal or vertical movement can be performed, and it is difficult to achieve precise adjustment of multiple degrees of freedom. During the irradiation process, the position of the sample may be offset due to thermal expansion, mechanical vibration or other factors, resulting in uneven irradiation or experimental result deviation. The existing device lacks the function of real-time monitoring and correcting the position of the sample.

[0053] 2) Difficulty in ensuring irradiation uniformity:

[0054] The material sample needs to be uniformly irradiated during the irradiation process to ensure the accuracy and reliability of the experimental results. However, traditional irradiation devices often cannot ensure that all parts of the sample are uniformly irradiated. For example, the edge part of the sample may receive less irradiation dose due to shielding or uneven beam distribution. In order to achieve uniform irradiation, some experiments will use the method of rotating the sample, but the existing rotating device is usually complex in structure and inconvenient to adjust, and is difficult to integrate with the irradiation device.

[0055] 3) Insufficient sample stability:

[0056] During irradiation, the sample needs to be kept stable to avoid experimental errors caused by vibration, tilting or other mechanical interference. However, existing irradiation devices often lack effective sample stabilization measures. For example, the sample may shake during irradiation due to the movement of the mechanical arm or the impact of the particle beam. Such shaking can affect the uniformity of sample irradiation and even cause sample damage.

[0057] 4) Low experimental efficiency:

[0058] Traditional irradiation experimental devices often require a lot of time during sample installation, adjustment and replacement. Sample installation and adjustment usually require manual operation, and the adjustment accuracy is difficult to guarantee.

[0059] Therefore, the present application provides an experimental platform and control method for particle accelerator material irradiation to solve the above technical problems.

[0060] The present application provides an experimental platform for particle accelerator material irradiation, as shown in Figure 1 and Figure 2 , comprising a six-axis mechanical arm, a camera and light spot recognition system, a rotating gripper and an integrated control system. The integrated control system controls the six-axis mechanical arm, the camera and the light spot recognition system, and the rotating gripper; the camera and the light spot recognition system are fixed at the front end of the six-axis mechanical arm; the rotating gripper is fixed at the execution end of the six-axis mechanical arm.

[0061] Among them, the six-axis mechanical arm refers to a mechanical operating part with six degrees of freedom along the X, Y, Z axes and around the X, Y, Z axes, used to control the position and attitude of the sample.

[0062] The camera and light spot recognition system is a system composed of a camera and a data processing module, used to capture particle beam light spot image data on the scintillator in real time, and analyze the image data through an algorithm to complete light spot center positioning processing and obtain the light spot center position.

[0063] The rotating gripper is a component installed at the execution end of the mechanical arm, which can hold the sample and rotate around a specific axis, used to hold and drive the sample to rotate 360° around the horizontal axis parallel to the particle beam.

[0064] The integrated control system is the core control unit of the experimental platform, which establishes a connection with each component through electrical signals, can obtain the running data feedback from the six-axis mechanical arm, the camera and the light spot recognition system, and the rotating gripper, analyzes and operates the data, and outputs control instructions, finally makes the six-axis mechanical arm adjust the attitude to compensate for the position deviation, the rotating gripper to stabilize the holding and rotate at a uniform speed, ensures that the sample is always in the center of the irradiation beam and is uniformly irradiated.

[0065] The experimental platform for particle accelerator material irradiation includes a six-dimensional mechanical arm, a camera and a light spot recognition system, a rotating gripper, and an integrated control system. The camera and the light spot recognition system are used to collect particle beam light spot images on the scintillator in real time, and transmit the data to the integrated control system. The integrated control system accurately calculates the real-time spatial position deviation of the sample relative to the irradiation beam center. The six-dimensional mechanical arm is driven to dynamically adjust the posture to compensate for the deviation, and the rotating gripper is controlled to stably hold the sample and rotate 360 degrees, realizing accurate and flexible positioning, uniform irradiation, stable holding, real-time monitoring and correction of the sample, thereby improving the accuracy, reliability and efficiency of the experiment, and providing an efficient, stable and intelligent experimental tool for particle accelerator material irradiation research.

[0066] In an exemplary embodiment, the experimental platform further includes a level; the level is integrated on the six-dimensional mechanical arm; and the integrated control system controls the level.

[0067] The level is a measuring component for detecting whether an object is in a horizontal or vertical state, and the level obtains the horizontal state data of the sample through a built-in sensor.

[0068] The integrated control system is configured to send a posture adjustment instruction to the six-dimensional mechanical arm according to the horizontal state data fed back by the level, and correct the sample inclination angle through the rotational degrees of freedom of the mechanical arm, so that the sample is perpendicular to the horizontal plane.

[0069] The embodiments of the present application can monitor the horizontal state of the sample in real time during the initial placement and the experimental process by adding the level, avoid the irradiation area from deviating due to sample inclination, and further ensure the relative position accuracy of the sample and the irradiation beam.

[0070] In an exemplary embodiment, the experimental platform further includes an accelerometer, and the accelerometer is integrated on the six-dimensional mechanical arm; and the integrated control system controls the accelerometer.

[0071] The accelerometer is a sensor for measuring the acceleration of an object in motion, and can capture acceleration change data of the six-dimensional mechanical arm during motion, identify whether the mechanical arm has excessive impact or vibration, and feed back the data to the integrated control system.

[0072] The integrated control system is configured to analyze whether the motion state of the mechanical arm is stable according to the acceleration data fed back by the accelerometer. If the acceleration exceeds a preset threshold, it indicates that the mechanical arm has severe vibration, and the system adjusts the motion parameters of the mechanical arm (such as reducing the motion speed and optimizing the motion trajectory) to eliminate the influence of vibration on the sample and avoid the sample from loosening or deviating due to vibration.

[0073] In the embodiments of the present application, the addition of the accelerometer can monitor the stability of the motion of the mechanical arm in real time, and suppress vibration by dynamically adjusting the motion parameters, thereby protecting the sample from vibration damage and avoiding irradiation position deviation caused by vibration, and improving the stability of the experimental process.

[0074] In an exemplary embodiment, the six-dimensional mechanical arm is installed in a target chamber of a particle accelerator. The "target chamber" refers to a sealed space in the particle accelerator for placing a sample and realizing the interaction of a particle beam with the sample, thereby providing a safe and stable environment for irradiation experiments.

[0075] The six-dimensional mechanical arm has translational degrees of freedom along the X, Y, and Z axes (can drive the sample to move linearly in three-dimensional space), and rotational degrees of freedom around the X, Y, and Z axes (can adjust the inclination angle and orientation of the sample), and through the coordinated action of the six degrees of freedom, the sample can be precisely adjusted to any position and attitude in the target chamber.

[0076] In the embodiments of the present application, the six-dimensional mechanical arm is directly installed in the target chamber, which shortens the distance between the mechanical arm and the irradiation area and reduces the motion error; the design of the six degrees of freedom ensures that the sample can adapt to different irradiation requirements and be flexibly adjusted to the optimal experimental attitude, thereby improving the applicability of the platform.

[0077] In an exemplary embodiment, a scintillator with a 10mm circular hole is arranged in front of the sample, and the scintillator will generate a light spot under the action of the particle beam. The 10mm circular hole is the best balance between beam utilization, irradiation uniformity, heat management difficulty, and sample standardization. It is large enough to effectively utilize the beam and avoid local overheating, and small enough to ensure high uniformity of the irradiation area and match the standard sample size required by the back-end physics test (such as a tensile specimen with a gauge length of 10mm), thereby ensuring the representativeness and reliability of the experimental results.

[0078] Further, the scintillator material needs to be sensitive to the particle beam and have good light emission characteristics. In particle accelerator irradiation experiments, commonly used scintillator materials include inorganic scintillators such as LYSO:Ce, BGO, NaI:Tl, and CsI:Tl, and organic scintillators such as plastic scintillator BC-408. These materials have high density, high light output, and fast decay characteristics, and can efficiently convert particle beam energy into visible light. Among them, LYSO:Ce is widely used due to its high light yield (~32,000 photons / MeV) and fast decay time (40ns); BGO is known for its high density (7.13g / cm 3 ) and radiation damage resistance; and plastic scintillator provides extremely fast response time (~2ns) and good machinability, suitable for making complex-shaped scintillators. The selection of materials needs to consider the type of particles, energy range, time resolution, and radiation damage resistance requirements.

[0079] In the embodiment of the present application, the scintillator with a 10mm circular hole optimizes beam utilization and irradiation uniformity, and matches the standard sample size; the selectability of different types of scintillators enables the platform to adapt to various irradiation experimental requirements, improving the versatility of the platform and the reliability of experimental results.

[0080] In an exemplary embodiment, as shown in FIG. X, the present application provides a control method for an experimental platform for particle accelerator material irradiation, which is applied to the integrated control system in FIG. X. For example, the method includes the following steps: Figure 3

[0081] S101, control the six-dimensional mechanical arm to adjust the initial state of the sample to make the sample perpendicular to the horizontal plane.

[0082] In the embodiment of the present application, the sample to be irradiated is installed on the rotating gripper at the front end of the mechanical arm, and the integrated control system starts the level meter and accelerometer: the level meter detects the current horizontal state data of the sample to determine whether the sample is tilted; the accelerometer monitors the acceleration data during the movement of the mechanical arm to avoid excessive vibration during the adjustment process; the system sends adjustment instructions to the six-dimensional mechanical arm according to the two types of data, corrects the sample tilt angle through the rotational freedom of the mechanical arm, and finally makes the sample reach the initial state of being perpendicular to the horizontal plane.

[0083] S102, control the camera and the light spot recognition system to capture the particle beam light spot image data on the scintillator in real time, and perform light spot center positioning processing on the particle beam light spot image data to obtain the light spot center position.

[0084] In the embodiment of the present application, the particle accelerator is started, and the particle beam acts on the scintillator after passing through the 10mm circular hole of the scintillator, causing the scintillator to generate a visible light spot; the camera captures the light spot image in real time, and transmits the original image data to the light spot recognition system; the system processes the image data through the built-in algorithm to calculate the position of the light spot center in the image.

[0085] S103, control the rotating gripper to hold and drive the sample to rotate 360° around the horizontal axis parallel to the particle beam.

[0086] In the embodiment of the present application, during the irradiation process, the gripper drives the sample to rotate 360°, so that each part of the sample uniformly receives irradiation. The gripper drives the sample to rotate 360° around the horizontal axis parallel to the particle beam, while the scintillator is independently fixed in the beam path and located in front of the sample, so that the sample and the gripper will not block the scintillator during rotation. At the same time, the level meter and the accelerometer monitor the sample state in real time to ensure its stability and perpendicularity.

[0087] ​S104, acquire the data of the six-dimensional mechanical arm, the camera and the light spot recognition system, and the rotating gripper feedback, and perform data processing to output a control instruction, so that the six-dimensional mechanical arm adjusts the posture to compensate for the positional deviation, the rotating gripper stabilizes the clamping and rotates at a uniform speed, so as to ensure that the sample is always in the center of the irradiation beam and is uniformly irradiated.

[0088] In the embodiments of the present application, the integrated control system continuously receives feedback data of each component, i.e., the camera and the light spot recognition system feedback the light spot center position data, the six-dimensional mechanical arm feedbacks the current position and posture data, and the rotating gripper feedbacks the clamping force and rotating speed data; the system comprehensively analyzes these data, and if it finds that the light spot center deviates, it sends a posture adjustment instruction to the six-dimensional mechanical arm; if it finds that the clamping force of the rotating gripper is insufficient or the rotating speed is abnormal, it sends a parameter adjustment instruction to the rotating gripper, so as to ensure the experimental accuracy through real-time closed-loop control.

[0089] The control method of the embodiments of the present application realizes accurate control of the whole process from sample installation to irradiation; each step is closely linked, which not only ensures that the initial state of the sample is compliant, but also effectively improves the accuracy and stability of the experiment through real-time monitoring and correction of deviations.

[0090] In one exemplary embodiment, based on the above embodiments, as shown in Figure 4 The embodiments of the present application relate to a process of locating the center of a particle beam light spot image data to obtain the light spot center position, which includes the following steps:

[0091] S201, performing Gaussian filtering processing on the particle beam light spot original image data to obtain denoised light spot image data.

[0092] First, to realize accurate spatial calculation, four coordinate systems need to be defined:

[0093] Image pixel coordinate system (u, v): taking the upper left corner of the camera picture as the origin, the unit is pixel.

[0094] Image physical coordinate system (x, y): taking the center of the camera optical axis as the origin, the unit is millimeter.

[0095] Mechanical arm end tool coordinate system (X_t, Y_t, Z_t): taking the center of the gripper or the sample as the origin, moving with the mechanical arm.

[0096] World coordinate system (X_w, Y_w, Z_w): taking the ideal particle beam center axis as the reference.

[0097] The control target is to make the sample center in the tool coordinate system continuously coincide with the beam center in the world coordinate system.

[0098] Then, after the camera captures the light spot on the scintillator, the light spot center is accurately calculated through the following image processing steps:

[0099] First, image preprocessing is performed, and the particle beam spot original image I(u, v) is Gaussian filtered to suppress noise:

[0100] G(u, v) = I(u, v) * K gaussian (σ) (1)

[0101] where * represents convolution operation, K gaussian (σ) is a Gaussian kernel with a standard deviation of σ.

[0102] S202, the adaptive threshold method is used to binarize and segment the denoised spot image data, and the binarized image data containing only the spot region is obtained.

[0103] The adaptive threshold method (such as Otsu's Method) is used to binarize the filtered image G(u, v) in the embodiment of the application, and the spot and the background are separated.

[0104]

[0105] S203, in the spot region of the binarized image data, the coordinates and corresponding gray values of all pixels in the spot region are statistically processed, and the sum of the product of the gray value of each pixel in the region and its own coordinates is calculated, and then divided by the sum of the gray values of all pixels in the region, to obtain the spot center position; the spot center position is the coordinate data of the spot center in the image pixel coordinate system.

[0106] In the embodiment of the application, in order to achieve sub-pixel accuracy, the gray centroid method is used on the original gray image in the binarized region. This method is strong in anti-interference and high in accuracy. Assuming that there are N pixels in the spot region, their coordinates and gray values are (u i ,v i ) and I(u i ,v i ). The calculation formula of the spot center (u c ,v c ) is:

[0107]

[0108] In the embodiment of the application, through the step-by-step processing of "coordinate system definition - denoising - segmentation - centroid calculation", a unified coordinate reference is established, noise is suppressed and the background is separated through the algorithm, and finally high-precision spot center positioning is realized.

[0109] In an exemplary embodiment, based on the above embodiment, as shown in Figure 5 , the method of the embodiment of the application further includes the following steps:

[0110] S301, pre-calibration is performed on the camera to obtain an intrinsic matrix of the camera and an extrinsic matrix of the camera relative to the end of the robot arm.

[0111] In the embodiment of the application, the intrinsic matrix K of the camera and the extrinsic matrix [R|t] relative to the end of the robot arm are obtained through pre-calibration.

[0112]

[0113] The intrinsic matrix K is used to connect the image physical coordinates (x, y) and the pixel coordinates (u, v), (fx, fy) is the focal length in pixels, (cx, cy) is the principal point coordinates (origin of the image physical coordinate system). x y

[0114] S302, based on the pixel coordinate data of the spot center in the image pixel coordinate system and the intrinsic matrix of the camera, the pixel coordinate data is subjected to inverse projection processing to obtain the coordinate data of the spot center in the image physical coordinate system.

[0115] The embodiment of the application subjects the pixel coordinate data to inverse projection processing, that is, the pixel coordinates (u c ,v c ) of the spot center are converted back to the image physical coordinates (x c ,y c ) through the inverse matrix K -1 of the intrinsic matrix.

[0116]

[0117] S303, according to the known fixed distance between the scintillator and the sample, the coordinate data of the spot center in the image physical coordinate system is mapped to the plane of the six-dimensional robot arm end tool coordinate system to obtain the projection coordinates of the spot center in the tool coordinate system.

[0118] In the embodiment of the application, since the scintillator is fixed at a known distance d in front of the sample, it can be approximately considered that the projection position of the spot center on the tool coordinate system X t -O-Y t plane is (x c ,y c ).

[0119] S304, the projection coordinates of the spot center in the tool coordinate system are compared with the target coordinates of the preset spot target in the tool coordinate system, and the difference between the projection coordinates of the spot center in the tool coordinate system and the preset spot target calculated in the tool coordinate system in the plane is obtained to obtain the spatial position deviation data of the sample relative to the center of the irradiation beam; the spatial position deviation data is used to ensure that the sample is always in the center of the irradiation beam and is uniformly irradiated.​​

[0120] In this embodiment, the system's preset target is that the light spot is located at the image center (u0, v0), and its corresponding image physical coordinates are (x0, y0). Therefore, in the tool coordinate system X... t -OY t Positional deviation △P on the plane t for:

[0121]

[0122] Among them, this △P t The vector represents the lateral displacement that the robotic arm needs to compensate for. Based on the position information of the light spot, the robotic arm adjusts its posture in real time to ensure that the sample remains at the center of the irradiation beam.

[0123] This application embodiment uses camera calibration and multi-step coordinate transformation to accurately convert the center position of the light spot in the image dimension into a spatial position deviation that can be recognized by the robotic arm.

[0124] In one exemplary embodiment, based on the above embodiments, such as Figure 6 As shown, the method in this embodiment further includes the following steps:

[0125] S401 inputs the spatial position deviation data of the sample relative to the center of the irradiation beam into the built-in PID controller for motion command calculation and processing, and obtains the attitude adjustment command of the six-dimensional robotic arm.

[0126] In this embodiment, a proportional-integral-derivative (PID) controller is used to calculate the motion commands of the robotic arm. The PID controller can effectively smooth the motion and avoid oscillations.

[0127]

[0128] in:

[0129] It is the motion command at time t;

[0130] It is the positional deviation at time t;

[0131] K p K d K i These are the gain parameters of the PID controller, which need to be tuned according to the dynamic characteristics of the robotic arm to ensure that deviations are eliminated quickly, stably, and without overshoot.

[0132] S402, based on the attitude adjustment command of the six-dimensional robotic arm, drives the six-dimensional robotic arm to perform movement adjustment processing to correct spatial position deviations and ensure that the sample is always in the center of the irradiation beam.

[0133] In the embodiments of the present application, the motion instruction in the tool coordinate system is converted into a motion instruction in the world coordinate system. Through the inverse kinematics algorithm of the mechanical arm, the angle or distance of each joint to be rotated or moved is solved, and is sent to the servo driver for execution, thereby driving the sample to move and offset the position deviation.

[0134] In the embodiments of the present application, as shown in Figure 7 Through the smooth operation of the PID controller and the precise conversion of the inverse kinematics, the mechanical arm can realize rapid and stable posture adjustment according to the spatial position deviation, effectively compensate the deviation of the sample from the center of the irradiation beam, and ensure that the sample is always in the ideal irradiation position, thereby further improving the experimental precision.

[0135] It should be understood that, although each step in the flowchart involved in each of the above embodiments is displayed in sequence according to the arrow, these steps are not necessarily executed in sequence according to the arrow. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other sequences. Moreover, at least part of the steps in the flowchart involved in each of the above embodiments can include multiple steps or stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of these steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least part of other steps or steps or stages in other steps.

[0136] Based on the same inventive concept, the embodiments of the present application also provide a control device for the experimental platform for particle accelerator material irradiation for implementing the control method for the experimental platform for particle accelerator material irradiation as described above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme described in the above method, so the specific limitations in one or more control device embodiments for the experimental platform for particle accelerator material irradiation provided below can refer to the limitations of the control method for the experimental platform for particle accelerator material irradiation in the above, which will not be repeated here.

[0137] In one embodiment, as shown in Figure 8 A control device 500 for the experimental platform for particle accelerator material irradiation is provided, and the device comprises:

[0138] A state adjustment module 501 is configured to control the initial state of the sample to be adjusted by the six-dimensional mechanical arm, so that the sample is perpendicular to the horizontal plane.

[0139] The position determination module 502 is configured to control the camera and the light spot identification system to capture particle beam light spot image data on the scintillator in real time, and to perform light spot center positioning processing on the particle beam light spot image data to obtain light spot center positions.

[0140] The rotating module 503 is configured to control the rotating gripper to hold and drive the sample to rotate 360 degrees around a horizontal axis parallel to the particle beam.

[0141] The mechanical arm adjustment module 504 is configured to acquire data fed back by the six-dimensional mechanical arm, the camera and the light spot identification system, and the rotating gripper, and to perform data processing to output control instructions, so that the six-dimensional mechanical arm adjusts the posture to compensate for the position deviation, the rotating gripper stably holds and uniformly rotates, so as to ensure that the sample is always in the center of the irradiation beam and is uniformly irradiated.

[0142] The above-mentioned various modules in the control device of the experimental platform for particle accelerator material irradiation can be realized by software, hardware, or a combination thereof. The above-mentioned various modules can be embedded in or independent of the processor in the computer device in hardware form, or can be stored in the memory in the computer device in software form, so as to be called and executed by the processor to perform the operations corresponding to the above-mentioned various modules.

[0143] It should be noted that the user information (including but not limited to user equipment information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in the present application are all information and data authorized by the user or authorized by all parties, and the collection, use and processing of the related data need to comply with the relevant laws, regulations and standards of the relevant countries and regions.

[0144] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer readable storage medium, and when the computer program is executed, the processes of the above-mentioned embodiments of the methods can be included. Any reference to memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (Read-Only Memory, ROM), magnetic tape, floppy disk, flash memory, optical storage, high-density embedded non-volatile memory, resistive memory (ReRAM), magnetoresistive random access memory (Magnetoresistive Random Access Memory, MRAM), ferroelectric memory (Ferroelectric Random Access Memory, FRAM), phase change memory (Phase Change Memory, PCM), graphene memory, etc. Volatile memory can include random access memory (Random Access Memory, RAM) or external cache memory, etc. As an illustration but not limitation, RAM can be in various forms, such as static random access memory (Static Random Access Memory, SRAM) or dynamic random access memory (Dynamic Random Access Memory, DRAM), etc. The database involved in the embodiments provided in the present application can include at least one of a relational database and a non-relational database. The non-relational database can include a distributed database based on a block chain, etc., without being limited thereto. The processor involved in the embodiments provided in the present application can be a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., without being limited thereto.

[0145] Any combination of the technical features of the above embodiments can be made. In order to make the description simple, all possible combinations of the technical features in the above embodiments are not described, however, as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the present application.

[0146] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of protection of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. An experimental platform for irradiating materials in a particle accelerator, characterized in that, The system includes a six-dimensional robotic arm, a camera and light spot recognition system, a rotary gripper, and an integrated control system. The integrated control system controls and connects the six-dimensional robotic arm, the camera and light spot recognition system, and the rotary gripper. The camera and light spot recognition system is fixed to the front end of the six-dimensional robotic arm. The rotary gripper is fixed to the execution front end of the six-dimensional robotic arm. The six-dimensional robotic arm is used to control the position and orientation of the sample; The camera and spot recognition system are used to capture particle beam spot image data on the scintillator in real time, and perform spot center localization processing on the particle beam spot image data to obtain the spot center position. The rotary gripper is used to hold and drive the sample to rotate 360° around a horizontal axis parallel to the particle beam. The integrated control system is used to acquire data from the six-dimensional robotic arm, the camera and light spot recognition system, and the rotating gripper, and to process the data and output control commands to enable the six-dimensional robotic arm to adjust its posture to compensate for positional deviations and the rotating gripper to stably hold and rotate at a uniform speed, so as to ensure that the sample is always in the center of the irradiation beam and is uniformly irradiated.

2. The experimental platform for particle accelerator material irradiation according to claim 1, characterized in that, It also includes a level; the level is integrated on the six-dimensional robotic arm; the integrated control system controls and connects to the level; The level is used to acquire the horizontal state data of the sample; The integrated control system is used to send adjustment commands to the six-dimensional robotic arm based on the horizontal state data, so that the sample is perpendicular to the horizontal plane.

3. The experimental platform for particle accelerator material irradiation according to claim 2, characterized in that, It also includes an accelerometer, which is integrated on the six-dimensional robotic arm; the integrated control system controls the accelerometer. The accelerometer is used to acquire acceleration data of the six-dimensional robotic arm during its movement. The integrated control system is used to adjust the motion state of the robotic arm based on the acceleration data to eliminate the influence of vibration on the sample.

4. The experimental platform for particle accelerator material irradiation according to claim 3, characterized in that, The six-dimensional robotic arm is installed in the target chamber of the particle accelerator and has translational degrees of freedom along the X, Y, and Z axes as well as rotational degrees of freedom about the X, Y, and Z axes.

5. The experimental platform for particle accelerator material irradiation according to claim 1, characterized in that, The scintillator is a 10mm circular hole; the material of the scintillator includes inorganic scintillators such as LYSO:Ce, BGO, NaI:Tl and CsI:Tl, as well as plastic scintillator BC-408.

6. A control method for an experimental platform used for material irradiation in a particle accelerator, characterized in that, The method includes: The six-dimensional robotic arm is controlled to adjust the initial state of the sample so that the sample is perpendicular to the horizontal plane; The camera and spot recognition system are controlled to capture particle beam spot image data on the scintillator in real time, and the spot center is located by performing spot center localization processing on the particle beam spot image data to obtain the spot center position. Control the rotating gripper to hold and drive the sample to rotate 360° around a horizontal axis parallel to the particle beam; Data from the six-dimensional robotic arm, the camera and light spot recognition system, and the rotating gripper are acquired and processed to output control commands. This enables the six-dimensional robotic arm to adjust its posture to compensate for positional deviations, and the rotating gripper to stably hold and rotate at a uniform speed, ensuring that the sample is always at the center of the irradiation beam and is uniformly irradiated.

7. The control method for the experimental platform for particle accelerator material irradiation according to claim 6, characterized in that, The step of performing spot center localization processing on the particle beam spot image data to obtain the spot center position includes: Gaussian filtering was applied to the original particle beam spot image data to obtain the denoised spot image data. An adaptive thresholding method is used to perform binarization segmentation on the denoised spot image data to obtain binarized image data containing only the spot region. Within the spot area of ​​the binarized image data, the coordinates of all pixels within the spot area and their corresponding gray values ​​are statistically processed. The sum of the products of the gray value of each pixel within the area and its own coordinates is calculated, and then divided by the sum of the gray values ​​of all pixels within the area to obtain the center position of the spot. The center position of the spot is the coordinate data of the center of the spot in the image pixel coordinate system.

8. The control method for the experimental platform for particle accelerator material irradiation according to claim 7, characterized in that, The method further includes: The camera is pre-calibrated to obtain the camera's intrinsic parameter matrix and the camera's extrinsic parameter matrix relative to the end of the robotic arm. Based on the pixel coordinate data of the light spot center in the image pixel coordinate system and the intrinsic parameter matrix of the camera, the pixel coordinate data is back-projected to obtain the coordinate data of the light spot center in the image physical coordinate system. Based on the known fixed distance between the scintillator and the sample, the coordinate data of the light spot center in the image physical coordinate system is mapped onto the plane of the tool coordinate system at the end of the six-dimensional robotic arm to obtain the projected coordinates of the light spot center in the tool coordinate system. The projected coordinates of the light spot center in the tool coordinate system are compared with the target coordinates of the preset light spot target in the tool coordinate system. The difference between the projected coordinates of the light spot center in the tool coordinate system and the preset light spot target in the plane of the tool coordinate system is calculated to obtain the spatial position deviation data of the sample relative to the center of the irradiation beam. The spatial position deviation data is used to ensure that the sample is always in the center of the irradiation beam and is uniformly irradiated.

9. The control method for the experimental platform for particle accelerator material irradiation according to claim 8, characterized in that, The method further includes: The spatial position deviation data of the sample relative to the center of the irradiation beam is input into the built-in PID controller for motion command calculation and processing to obtain the attitude adjustment command of the six-dimensional robotic arm. The six-dimensional robotic arm is driven by the posture adjustment command to perform movement adjustment processing to correct spatial position deviations and ensure that the sample is always in the center of the irradiation beam.

10. A control device for an experimental platform used for material irradiation in a particle accelerator, characterized in that, The device includes: The state adjustment module is used to control the six-dimensional robotic arm to adjust the initial state of the sample so that the sample is perpendicular to the horizontal plane. The position determination module is used to control the camera and the spot recognition system to capture the particle beam spot image data on the scintillator in real time, and to perform spot center positioning processing on the particle beam spot image data to obtain the spot center position. The rotation module is used to control the rotating gripper to hold and drive the sample to rotate 360° around a horizontal axis parallel to the particle beam. The robotic arm adjustment module is used to acquire data from the six-dimensional robotic arm, the camera and light spot recognition system, and the rotating gripper, and to process the data and output control commands to make the six-dimensional robotic arm adjust its posture to compensate for position deviations, and to make the rotating gripper stably hold and rotate at a uniform speed to ensure that the sample is always in the center of the irradiation beam and is uniformly irradiated.

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