A method and device for locating and tracking radioactive sources based on a gimbal.

Abstract

This invention provides a method and device for locating and tracking radioactive sources based on a gimbal, relating to the field of radioactive source detection and tracking technology. The method includes: acquiring detection data from multiple crystal detectors when locating and tracking a radioactive source in the environment; determining the presence of a radioactive source in the environment based on the multiple detection data; determining the relative positional relationship between the radioactive source and the detection center axis of the main crystal detector based on the multiple detection data when the presence of a radioactive source is confirmed; and driving the gimbal according to the relative positional relationship so that the detection center axis of the main crystal detector points to the position of the radioactive source. Through the intelligent fusion of multiple crystal detectors and a rotating gimbal, real-time, high-precision, and low-cost location and tracking of radioactive sources is achieved, and intuitive optical visual confirmation can be provided.

Description

Technical Field

[0001] This invention relates to the field of radioactive source detection and tracking technology, and more specifically, to a method and device for radioactive source positioning and tracking based on a gimbal. Background Technology

[0002] With the widespread application of nuclear technology, the safety supervision of radioactive sources is becoming increasingly important. Traditional radioactive source detection technologies mainly include fixed radiation monitoring stations and handheld radiation detectors. While fixed radiation monitoring stations can achieve regional coverage, they cannot perform dynamic tracking; handheld radiation detectors, although portable, have low positioning accuracy, rely on manual judgment of the radioactive source's direction, and are inefficient. Although the Compton camera and coded aperture camera technologies developed in recent years can achieve gamma-ray imaging and direction detection, they suffer from problems such as system complexity, high cost, and poor real-time performance, making it difficult to meet the needs of rapid response and portable applications.

[0003] Specifically, the commonly used techniques for detecting the direction of radioactive sources mainly include the following:

[0004] 1. Single-detector rotational scanning method: This method uses a single detector to perform a 360° scan by manual or electric rotation, and determines the direction of the radiation source by comparing the count rates at different angles. This method has the following drawbacks: long scanning time, inability to track moving radiation sources in real time; limited sensitivity of the single detector and short detection distance; and low efficiency due to the need for a complete circular scan to determine the direction.

[0005] 2. Collimated Detector Method: A lead or tungsten alloy collimator is installed at the front of the detector to limit the detection field of view. The direction of the radiation source is determined by the collimator's pointing. The disadvantages of this method include: the collimator significantly reduces detection efficiency and weakens sensitivity; the collimator increases the weight of the device, hindering portable applications; and the limited field of view makes it easy to miss radiation sources.

[0006] 3. Compton Camera Imaging Method: The Compton camera utilizes the Compton scattering principle of gamma rays for direction detection, typically consisting of a scattering detector layer and an absorption detector layer. By measuring the scattering angle and scattering position, the incident direction cone of the gamma rays is reconstructed, and multiple events are superimposed to form an image of the radiation source. This method has the following significant drawbacks: the system structure is extremely complex, requiring high-precision position-sensitive detectors and sophisticated double- or multi-layer detector arrays, making manufacturing difficult; the Compton scattering cross section varies with energy, resulting in extremely low detection efficiency for low-energy gamma rays (less than 200 keV), and a narrow applicable energy range; it requires complex coincidence measurement electronics and event reconstruction algorithms, leading to large data processing volumes and poor real-time performance; for weak radiation sources, a long integration time is required to obtain a clear image, hindering rapid response; and the system cost is extremely high, typically in the millions of yuan range.

[0007] 4. Encoded Aperture Imaging Method: This method modulates incident gamma rays using a specially designed coded aperture mask and reconstructs the radiation source direction image through a decoding algorithm. The main drawbacks of this method are: narrow field of view, complex algorithm, low detection efficiency, poor real-time performance, unsuitability for fast-response scenarios; high requirements for detector pixel resolution, resulting in high cost; poor imaging quality and insufficient positioning accuracy under low dose rate conditions.

[0008] In summary, there is an urgent need for a dynamic positioning and tracking technology solution for radioactive sources that can balance real-time performance, accuracy, efficiency, and cost. Summary of the Invention

[0009] In view of this, the purpose of the present invention is to provide a method and device for locating and tracking radioactive sources based on a gimbal. By intelligently integrating a polycrystalline detector with a rotating gimbal, the method achieves real-time, high-precision, and low-cost location and tracking of radioactive sources, and can provide intuitive optical visual confirmation.

[0010] To achieve the above objectives, the technical solutions adopted in the embodiments of the present invention are as follows:

[0011] In a first aspect, the present invention provides a method for locating and tracking a radiation source based on a gimbal, applied to a radiation detection device. The radiation detection device includes multiple crystal detectors and a gimbal. The multiple crystal detectors are mounted on the gimbal, including a master crystal detector and multiple sets of slave crystal detectors, with the detection center axes of any two crystal detectors having different directions. The method includes the following steps: when locating and tracking a radiation source in the environment, acquiring detection data from multiple crystal detectors; determining whether a radiation source exists in the environment based on the multiple detection data; when a radiation source is determined to exist in the environment, determining the relative positional relationship between the radiation source and the detection center axis of the master crystal detector based on the multiple detection data; and driving the gimbal according to the relative positional relationship so that the detection center axis of the master crystal detector points to the position of the radiation source.

[0012] It should be understood that by setting up multiple crystal detectors with different detection center axis directions and mounting them on a pan-tilt unit, when detecting radioactive sources in the environment, the detection data from multiple crystal detectors is acquired. Based on the multiple detection data, the presence of a radioactive source in the environment is determined. If the presence of a radioactive source is confirmed, the relative positional relationship between the radioactive source and the detection center axis of the main crystal detector is determined based on the multiple detection data. This then drives the pan-tilt unit to adjust the orientation of the main crystal detector, aligning its detection center axis towards the radioactive source. Based on this technical solution, not only can the presence of a radioactive source be detected, but the direction of the radioactive source can also be automatically determined and actively oriented. This reduces reliance on manual rotation scanning and manual judgment, improving the automation and efficiency of radioactive source location and tracking.

[0013] In an optional embodiment, each group of slave crystal detectors includes two crystal detectors with their detection center axes located on the same straight line but in opposite directions. The detection center axes of different groups of slave crystal detectors are located on different straight lines. The detection center axes of all slave crystal detectors are located on the same target plane, and the detection center axis of the main crystal detector is perpendicular to the target plane. Based on multiple detection data, the relative positional relationship between the radiation source and the detection center axis of the main crystal detector is determined, including: for each crystal detector, determining the detection vector of each crystal detector based on its detection center axis and crystal count rate; and determining the relative positional relationship between the radiation source and the detection center axis of the main crystal detector based on the vector sum of all detection vectors. It should be understood that by grouping the slave crystal detectors and performing vector summation based on the detection vectors of each crystal detector, the directional relationship of the radiation source relative to the main crystal detector can be quickly determined by integrating detection responses in multiple directions, thereby improving the accuracy of direction determination and the efficiency of coarse orientation.

[0014] In an optional embodiment, the multiple sets of slave crystal detectors include a first slave crystal detector group and a second slave crystal detector group. The detection center axis of the first slave crystal detector group is perpendicular to the detection center axis of the second slave crystal detector group, and the crystal sizes of the slave crystal detectors are consistent. For each crystal detector, the detection vector of each crystal detector is determined according to the detection center axis and the crystal count rate, including: for a slave crystal detector, the detection vector is determined according to the following first formula: Fi = Ri · ni; where Fi represents the detection vector of the i-th slave crystal detector among the multiple slave crystal detectors, Ri represents the crystal count rate of the i-th slave crystal detector, and ni represents the detection vector of the i-th slave crystal detector. The unit vector corresponding to the detection center axis of the crystal detector; for the main crystal detector, the detection vector is determined according to the following second formula: Fz = β·Rz·nz; where Fz represents the detection vector of the main crystal detector, Rz represents the crystal count rate of the main crystal detector, nz represents the unit vector corresponding to the detection center axis of the main crystal detector, and β represents the preset weighting coefficient; based on the vector sum of all detection vectors, the relative positional relationship between the radiation source and the detection center axis of the main crystal detector is determined, including: summing all detection vectors to obtain the predicted direction of the radiation source; the predicted direction is determined as the relative positional relationship between the radiation source and the detection center axis of the main crystal detector. It should be understood that by setting mutually perpendicular secondary crystal detector groups, a larger-sized main crystal detector, and weighting coefficients for the main crystal detection vector, the detection sensitivity and direction judgment capability of the main direction can be balanced, thereby improving the accuracy of the radiation source prediction direction and the system response speed.

[0015] In an optional embodiment, after driving the pan-tilt unit according to the relative positional relationship to point the detection center axis of the main crystal detector towards the position of the radiation source, the method further includes: determining the counting deviation rate of each group of slave crystal detectors; wherein the counting deviation rate represents the degree of deviation between the crystal counting rates of two slave crystal detectors in the same group; determining whether each counting deviation rate satisfies the locking condition; wherein the locking condition includes the counting deviation rate being less than a preset deviation threshold; if each counting deviation rate satisfies the locking condition and the crystal counting rate of the main crystal detector is the maximum counting rate, then it is determined that the radiation source is locked; if there is a counting deviation rate that does not satisfy the locking condition or the crystal counting rate of the main crystal detector is not the maximum counting rate, then a fine orientation process is performed to reduce the counting deviation rate of the slave crystal detector group that does not satisfy the locking condition, and the process returns to the step of determining the counting deviation rate of each group of slave crystal detectors. It should be understood that by combining the counting deviation rate of each group of slave crystal detectors with the maximum counting rate condition of the main crystal detector for locking judgment, it is possible to more accurately confirm whether the main crystal detector is aligned with the direction of the radiation source, thereby improving the locking accuracy and reducing the probability of false locking.

[0016] In an optional embodiment, the fine orientation process includes the following steps: obtaining the relationship between the count rates of two crystals in the slave crystal detector group that does not meet the locking condition; determining the crystal detector with the larger count rate in the slave crystal detector group that does not meet the locking condition based on the relationship; driving the pan-tilt unit to adjust the detection center axis of the main crystal detector so that the detection center axis of the main crystal detector deflects towards the detection center axis of the crystal detector with the larger count rate, thereby reducing the count deviation rate of the slave crystal detector group that does not meet the locking condition. It should be understood that by determining the fine orientation adjustment direction based on the count rate pattern of the slave crystal detectors in the same group, the count deviation rate can be quickly reduced, thereby improving the executability, convergence speed, and control stability of the fine orientation process.

[0017] In an optional embodiment, the method further includes: setting the rotation speed of the gimbal to a first rotation speed during the process of driving the gimbal according to the relative position relationship; and setting the rotation speed of the gimbal to a second rotation speed during the fine orientation process; wherein the first rotation speed is greater than the second rotation speed. It should be understood that by using a larger rotation speed in the coarse orientation stage and a smaller rotation speed in the fine orientation stage, both the initial response speed and the final locking accuracy can be balanced, thereby improving the overall tracking efficiency and control stability.

[0018] In an optional embodiment, determining whether a radioactive source exists in the environment based on multiple detection data includes: obtaining a dynamic tracking threshold for the radioactive source; obtaining the maximum detection data among the multiple detection data; and determining whether a radioactive source exists in the environment based on the relationship between the maximum detection data and the dynamic tracking threshold for the radioactive source. It should be understood that by comparing the maximum detection data among the multiple detection data with the dynamic tracking threshold, the detection of whether a radioactive source has entered the detection range can be more sensitive, thereby improving the reliability of automatic detection and tracking triggering of radioactive sources.

[0019] In an optional embodiment, the dynamic tracking threshold for the radioactive source is determined based on the background count rates of multiple crystal detectors. It should be understood that by determining the dynamic tracking threshold based on the background count rates of multiple crystal detectors, the threshold can be adaptively adjusted according to the environmental background level, thereby improving the environmental adaptability of radioactive source detection and reducing the probability of false alarms.

[0020] In an optional embodiment, the radiation detection device further includes an optical camera, a processing module, and a display module. Each crystal detector is electrically connected to the processing module, and both the optical camera and the display module are electrically connected to the processing module. The optical camera is mounted on the main crystal detector, and its optical axis is coaxially aligned with the detection center axis of the main crystal detector. After the step of driving the pan-tilt unit according to the relative position relationship to make the detection center axis of the main crystal detector point to the position of the radiation source, the method further includes: using the processing module to drive the display module to display the environmental image captured by the optical camera on the display module; and displaying a radiation source locking mark on the environmental image; wherein the radiation source locking mark corresponds to the position pointed to by the optical axis of the optical camera. It should be understood that by coaxially aligning the optical axis of the optical camera with the detection center axis of the main crystal detector and displaying the locking mark on the environmental image, the radiation source direction information can be intuitively displayed in the image, thereby improving the visualization and operational convenience of on-site positioning.

[0021] In a second aspect, the present invention provides a radiation detection device, comprising: multiple crystal detectors, a pan-tilt unit, and a processing module. The multiple crystal detectors and the pan-tilt unit are electrically connected to the processing module. The multiple crystal detectors are mounted on the pan-tilt unit. The multiple crystal detectors include a master crystal detector and multiple sets of slave crystal detectors. The detection center axes of any two crystal detectors are in different directions. The processing module is used to control the multiple crystal detectors and the pan-tilt unit to implement the method of any embodiment of the first aspect.

[0022] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, embodiments of the present invention are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments of the present invention will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a block diagram of a radiation detection device provided in an embodiment of the present invention;

[0025] Figure 2 A schematic diagram of a five-crystal detector provided in an embodiment of the present invention;

[0026] Figure 3 A flowchart illustrating a method for locating and tracking a radiation source based on a gimbal, provided in an embodiment of the present invention;

[0027] Figure 4 Another flowchart illustrating the gimbal-based radioactive source localization and tracking method provided in this embodiment of the invention;

[0028] Figure 5 This is another flowchart illustrating the gimbal-based method for locating and tracking radioactive sources provided in this embodiment of the invention.

[0029] Figure 6 A functional block diagram of a radiation source positioning and tracking control module provided in an embodiment of the present invention; Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0031] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0032] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0033] It should be noted that, where there is no conflict, the features in the embodiments of the present invention can be combined with each other.

[0034] This invention provides a technical solution including a gimbal-based method for locating and tracking radioactive sources and a radiation detection device, relating to the field of radioactive source detection and tracking technology. The method and device are applicable to scenarios such as nuclear facility operation, environmental protection monitoring, and public safety control, enabling real-time location locking, dynamic trajectory tracking, and precise direction confirmation of radioactive sources. They are particularly suitable for radioactive source monitoring tasks requiring rapid response and high-precision positioning, such as radioactive source leak investigation and illegal radioactive source tracking.

[0035] The technical solution provided by the present invention will now be described in conjunction with the accompanying drawings.

[0036] First, we introduce a radiation detection device provided in an embodiment of the present invention. Please refer to... Figure 1 The device 100 includes multiple crystal detectors 110, a gimbal 120, and a processing module 130, with the multiple crystal detectors 110 and the gimbal 120 all electrically connected to the processing module 130.

[0037] Multiple crystal detectors 110 are mounted on a gimbal 120 and rotate synchronously with the gimbal 120. The mounting method of the multiple crystal detectors 110 on the gimbal 120 can be configured according to actual application requirements. For example, the multiple crystal detectors 110 can be jointly fixed to the same mounting base, which is then fixed to the gimbal 120; or, the multiple crystal detectors 110 can be respectively fixed to different positions of a detector housing, which is then entirely mounted on the gimbal 120. As long as the multiple crystal detectors 110 can synchronously change direction under the movement of the gimbal 120, the application requirements of this embodiment can be met.

[0038] In this embodiment, the crystal detector 110 is used to respond to radiation and output detection data. Here, the detection data can be relevant data characterizing the intensity of the radiation response, such as crystal count rate, dose rate, energy spectrum data, or other data that can characterize the intensity and direction of radiation. Optionally, the crystal detector 110 can employ a scintillator detector structure, or other detection structures capable of radiation detection. In conjunction with specific embodiments of this application, the crystal detector 110 is preferably a scintillator detector, such as a NaI(Tl) scintillator crystal, a CsI scintillator crystal, or other scintillator crystal structures suitable for gamma-ray detection.

[0039] In an optional embodiment, when radiation enters the crystal detector 110, the scintillation crystal inside the crystal detector 110 generates a scintillation light signal under the radiation. The photoelectric sensor converts the scintillation light signal into an electrical signal, which is then amplified, shaped, filtered, and converted from analog to digital by the front-end circuit before outputting the corresponding detection data to the processing module 130. The photoelectric sensor can be a silicon photomultiplier tube (SiPM) or other photoelectric conversion device suitable for converting scintillation light signals into electrical signals.

[0040] In one optional embodiment, the gimbal 120 is used to drive the rotation of multiple crystal detectors 110 to adjust the overall pointing direction of the multiple crystal detectors 110, thereby achieving automatic orientation, locking, and continuous tracking of the radiation source. Optionally, the gimbal 120 can be a two-dimensional rotating gimbal with two mutually cooperating rotational degrees of freedom, such as a horizontal rotational degree of freedom and a pitch rotational degree of freedom, so as to adjust the orientation of the multiple crystal detectors 110 in different azimuth and height directions.

[0041] In an optional embodiment, the processing module 130 can be an electronic processing unit with data processing and control functions, such as including a processor, memory, and communication interface circuitry. The processing module 130 can be connected to multiple crystal detectors 110 via wired or wireless means, including but not limited to one or more of a serial interface, USB interface, Ethernet interface, or wireless communication interface. The processing module 130 can be integrated as a functional module within the radiation detection device 100, or it can be set independently of the multiple crystal detectors 110. In other words, the processing module 130 can be integrated with the multiple crystal detectors 110 into a single structure, or it can be used as an external processing unit to communicate with the multiple crystal detectors 110.

[0042] The processing module 130 is electrically connected to multiple crystal detectors 110 and is used to receive detection data output by the multiple crystal detectors 110 and analyze and process the detection data. Specifically, the processing module 130 can acquire in real time the crystal count rate, dose rate, or other data characterizing the intensity of radiation response output by each crystal detector 110, and based on this detection data, determine whether there is a radioactive source in the environment, determine the relative directional relationship of the radioactive source with respect to the detection center axis of the main crystal detector, and control the pan-tilt unit 120 to perform corresponding coarse orientation, fine orientation, locking, and tracking actions.

[0043] The processing module 130 can also be used to control multiple crystal detectors 110 and the gimbal 120. Specifically, the processing module 130 can send parameter configuration instructions and data acquisition instructions to multiple crystal detectors 110, and generate rotation control instructions for the gimbal 120 based on the detection data output by the multiple crystal detectors 110, so as to realize the functions of automatic detection of radioactive sources, direction determination, coarse orientation, fine orientation, lock confirmation and continuous tracking as described in this application.

[0044] In an optional embodiment, the radiation detection device 100 may further include a front-end signal conditioning circuit. Since the raw electrical signal output by the crystal detector 110 is typically weak, the front-end signal conditioning circuit can be used to preprocess the raw signal, such as amplifying, filtering, shaping, or performing analog-to-digital conversion, to improve the stability of the detection data and the accuracy of subsequent processing. The front-end signal conditioning circuit can be located inside the crystal detector 110 or at the input of the processing module 130; the specific structure can be configured according to the actual application requirements.

[0045] It should be understood that the specific structures and connection methods described above are merely illustrative examples. As long as it is possible to acquire radiation detection data in multiple directions and locate and track radiation sources based on the detection data, it can fall within the protection scope of this application.

[0046] The plurality of crystal detectors 110 includes a master crystal detector 111 and multiple sets of slave crystal detectors 112, and the directions of the detection center axes of any two crystal detectors are different. The master crystal detector 111 is the crystal detector used as the main detection direction, and its detection center axis is used to point towards the radiation source after adjustment by the pan-tilt unit 120. The slave crystal detectors 112 are crystal detectors used to assist in determining the direction and degree of deflection of the radiation source relative to the detection center axis of the master crystal detector 111.

[0047] The detection center axis refers to the direction of the center normal of the detection surface corresponding to the crystal detector 110, or the direction of the axis that characterizes the main response direction of the crystal detector 110.

[0048] It should be noted that the master crystal detector 111 and the slave crystal detector 112 in this application may be the same in terms of detection principle and basic structure. The main differences are in the installation position, detection center axis direction and crystal size.

[0049] In an optional embodiment, the device 100 may further include an optical camera 140 and a display module 150. Both the optical camera 140 and the display module 150 are electrically connected to the processing module 130. The optical camera 140 is positioned forward of the main crystal detector 111, and the optical axis of the optical camera 140 is coaxially aligned with the detection center axis of the main crystal detector 111. Here, "coaxial alignment" means that the imaging center direction of the optical camera 140 is substantially consistent with the main detection direction of the main crystal detector 111, so that when the radiation source is locked, the central region of the image acquired by the optical camera 140 corresponds to the direction of the radiation source.

[0050] Optionally, the optical camera 140 may include a visible light camera, a high-definition camera, an industrial camera, or other image acquisition devices suitable for capturing environmental images; the display module 150 may include a display screen, a touch screen, a liquid crystal display, a light-emitting diode display, or other display devices suitable for displaying images and information.

[0051] In an optional embodiment, each group of slave crystal detectors includes two crystal detectors with their detection center axes located on the same straight line and pointing in opposite directions, and the detection center axes of different groups of slave crystal detectors are located on different straight lines; or, each group of slave crystal detectors 112 includes two crystal detectors 110 with their detection center axes collinear and pointing in opposite directions, and the straight lines corresponding to the detection center axes of different groups of slave crystal detectors 112 are different from each other, and the detection center axes of all slave crystal detectors 112 are located in the same target plane, and the detection center axis of the main crystal detector 111 is perpendicular to the target plane. Here, the target plane refers to the reference plane formed by or located by the detection center axes of each group of slave crystal detectors 112, and this target plane can be used as a reference plane in determining the direction of the radiation source.

[0052] In an optional embodiment, the plurality of slave crystal detectors 112 includes a first slave crystal detector group and a second slave crystal detector group, wherein the detection center axis of the first slave crystal detector group is perpendicular to the detection center axis of the second slave crystal detector group. Optionally, the first slave crystal detector group can be used to determine the deviation in a first direction, and the second slave crystal detector group can be used to determine the deviation in a second direction. Further, the crystal size of each slave crystal detector 112 can be the same.

[0053] Optionally, the crystal size of the master crystal detector 111 can be larger than the crystal size of the slave crystal detector 112, so that the master crystal detector 111 has a relatively higher main direction detection sensitivity.

[0054] Optionally, the crystal size of the master crystal detector 111 can be equal to the crystal size of the slave crystal detector 112; or, the crystal size of the master crystal detector 111 can be smaller than the crystal size of the slave crystal detector 112. This application does not limit this.

[0055] The master crystal detector is used to enhance the response in the main detection direction, while the slave crystal detector is used to determine the direction deviation.

[0056] The above embodiment will be explained below using a five-crystal detector as an example. Please refer to [link / reference]. Figure 2 .

[0057] 1. Overall structure of a five-crystal detector

[0058] In this embodiment, the multiple crystal detectors 110 in the radiation detection device 100 can adopt a five-crystal detector structure. Specifically, the multiple crystal detectors 110 constitute a polycrystalline detector module, which can be a cuboid structure with crystal detectors 110 respectively disposed on its five outer surfaces.

[0059] The crystal detector 110 located in the Z+ axis plane serves as the main crystal detector 111, while the crystal detectors 110 located in the X+ axis plane, X- axis plane (located on the corresponding side not shown), Y+ axis plane (located on the corresponding side not shown), and Y- axis plane serve as slave crystal detectors 112. Here, the Z+ axis plane can be understood as the forward detection plane of the detector module, the X+ axis plane and X- axis plane correspond to the left and right lateral detection planes, respectively, and the Y+ axis plane and Y- axis plane correspond to the upper and lower lateral detection planes, respectively. Each crystal detector 110 is used to acquire gamma-ray signals and output corresponding detection data, such as crystal count rate and / or dose rate data.

[0060] In some embodiments, the optical camera 140 is positioned in front of the main crystal detector 111, and the optical axis of the optical camera 140 is coaxially aligned with the detection center axis of the main crystal detector 111. With this configuration, the optical camera 140 can be used to acquire environmental images in the current pointing direction of the main crystal detector 111, thereby achieving a correspondence between the radiation detection direction and the visual image.

[0061] In this embodiment, the polycrystalline detector module and the optical camera 140 are jointly mounted on the gimbal 120 and can rotate synchronously under the drive of the gimbal 120. Optionally, the gimbal 120 is a two-dimensional rotating gimbal with two mutually cooperating rotational degrees of freedom, used to adjust the overall pointing direction of the polycrystalline detector module and the optical camera 140.

[0062] The processing module 130 is electrically connected to the polycrystalline detector module, the optical camera 140, the pan-tilt unit 120, and the display module 150, respectively, and is used to perform functions such as data acquisition, data processing, direction determination, and control output. The display module 150 is used to provide a human-machine interface to display detection data, image data, and system status information, and to receive control commands input by the user.

[0063] Therefore, the polycrystalline detector module, optical camera 140, gimbal 120, processing module 130, and display module 150 can collectively form a closed-loop control system. Specifically, the polycrystalline detector module collects radiation response data, the processing module 130 analyzes and processes the radiation response data, and controls the gimbal 120 to adjust the pointing of the polycrystalline detector module and optical camera 140; after adjustment, detection data and image data are collected again, and it is determined whether the locking conditions are met; this cycle continues until the direction of the radiation source is locked and tracked. At the same time, the optical camera 140 can output an environmental image corresponding to the current detection direction, so that the operator can intuitively confirm the direction of the radiation source.

[0064] 2. Modular structure of a five-crystal detector

[0065] In this embodiment, the polycrystalline detector module has an overall rectangular parallelepiped structure. It should be noted that the specific dimensions of the parallelepiped can be designed according to the actual application scenario. For example, a structure with a length of 150 mm, a width of 150 mm, and a height of 100 mm can be used, but it is not limited to this.

[0066] 2.1 Crystal Layout and Function

[0067] like Figure 2 As shown, a crystal detector 110 is installed on each of the five outer surfaces of the cuboid structure.

[0068] The main crystal detector 111, located on the Z+ axis, can employ a relatively large crystal size, such as 150 mm × 150 mm × 40 mm. The main crystal detector 111 can be made of sodium iodide scintillation crystal (NaI(Tl)), cesium iodide scintillation crystal (CsI), or other scintillation crystal materials suitable for gamma-ray detection. Due to the relatively large detection area of ​​the main crystal detector 111, it can achieve high detection sensitivity and count rate response in the main detection direction.

[0069] An optical camera 140 may be disposed in front of the main crystal detector 111. For example, the optical camera 140 may be a high-definition camera with a resolution greater than or equal to 1080P and a field of view of 60° to 80°. Preferably, the optical axis of the optical camera 140 is coaxially aligned with the detection center axis of the main crystal detector 111 so that the direction of the image center is substantially consistent with the main detection direction of the main crystal detector 111.

[0070] The four slave crystal detectors 112 disposed in the X+, X-, Y+, and Y- axes can have the same dimensions, for example, 150 mm × 60 mm × 15 mm, and can use the same or similar scintillation crystal material as the master crystal detector 111. Specifically, two slave crystal detectors 112 located in the X+ and X- axes can form a group to determine directional deviation in the first direction (X-axis); two slave crystal detectors 112 located in the Y+ and Y- axes can form another group to determine directional deviation in the second direction (Y-axis). Optionally, the first and second directions are perpendicular to each other, for example, corresponding to the horizontal and vertical directions, respectively.

[0071] With the above arrangement, the main crystal detector 111 is used for main direction detection, and the secondary crystal detector 112 is used to assist in determining the deflection direction and degree of deviation of the radiation source relative to the detection center axis of the main crystal detector 111, thereby providing a basis for the subsequent control of the gimbal 120.

[0072] 2.2 Photoelectric Sensors and Electronic Structures

[0073] In some embodiments, a photoelectric sensor may be coupled to the back side of each crystal detector 110, i.e., the side opposite to the detection surface, for converting the scintillation light signal generated by the scintillation crystal under radiation into an electrical signal. The photoelectric sensor may be a silicon photomultiplier tube (SiPM) array, a photomultiplier tube (PMT), or other devices suitable for photoelectric conversion.

[0074] Each crystal detector 110 has a corresponding photoelectric sensor that can operate independently and output electrical signals separately. Accordingly, the radiation detection device 100 may also include a processing circuit for processing the electrical signals. The electronic processing circuit may include, for example, a preamplifier, a shaping circuit, a multi-channel pulse amplitude analyzer (MCA), and an analog-to-digital converter (A / D converter).

[0075] The preamplifier is used to amplify the weak electrical signal output by the photoelectric sensor; the shaping circuit is used to filter the signal and shape the pulse; the multi-channel pulse amplitude analyzer is used to perform energy discrimination according to the pulse amplitude to screen gamma-ray events within the target energy range; and the analog-to-digital converter is used to convert the analog signal into a digital signal so that the subsequent processing module 130 can perform digital processing.

[0076] In one exemplary embodiment, the electronic processing circuit can output the crystal count rate and dose rate data corresponding to each of the five crystal detectors 110 in real time. For example, the unit of crystal count rate can be cps (counts per second), and the unit of dose rate can be μSv / h. The data update frequency can be set to 10 Hz, but is not limited thereto.

[0077] By comparing the detection data from the five crystal detectors 110, the processing module 130 can determine the directional distribution of the radiation source relative to the multi-crystal detector module. For example, based on the difference in count rate between the main crystal detector 111 and each slave crystal detector 112, the deflection trend of the radiation source relative to the current detection direction can be determined, thereby providing a basis for the subsequent rotation control of the gimbal 120.

[0078] 3. Gimbal Structure and Drive Control

[0079] In this embodiment, the gimbal 120 is used to support the polycrystalline detector module and drive the polycrystalline detector module and the optical camera 140 to adjust their orientation. Optionally, the gimbal 120 is mounted below the polycrystalline detector module and is fixedly connected to the polycrystalline detector module via a mechanical connector.

[0080] 3.1 Rotational Degrees of Freedom and Range of Rotation

[0081] Optionally, the gimbal 120 adopts a two-axis orthogonal structure, which includes two cooperating rotation axes. The first rotation axis is used to achieve horizontal rotation, corresponding to azimuth adjustment; the second rotation axis is used to achieve vertical rotation, corresponding to pitch adjustment. Here, azimuth can be understood as the left-right rotation angle relative to the horizontal plane, and pitch can be understood as the up-down rotation angle relative to the horizontal plane.

[0082] In some implementations, the horizontal rotation range can be ±180° relative to the initial position, and the vertical rotation range can be -45° to +90°. Of course, the specific rotation range can be adjusted according to the application requirements.

[0083] With the aforementioned orthogonal arrangement of the two axes, the gimbal 120 can cover a large spatial area in front of the polycrystalline detector module. The base of the gimbal 120 can be fixed to a support platform or mobile carrier, such as a tripod, vehicle-mounted platform, or other load-bearing device.

[0084] 3.2 Drive System and Control Method

[0085] Rotational accuracy parameters: stepping accuracy ≤ 0.1° / step, positioning accuracy ≤ 0.5°, repeatability ≤ 0.3°.

[0086] In some embodiments, each rotation axis of the gimbal 120 may be equipped with a drive motor, such as a stepper motor. Optionally, the stepper motor is a hybrid stepper motor with a step angle, for example, from 0.9° to 1.8°. To improve rotational accuracy, a reduction gear and transmission mechanism, such as a reducer and gear transmission structure, may also be used.

[0087] The processing module 130 can output control signals to the gimbal 120 via a motor driver. These control signals include, for example, the number of pulses and the pulse frequency, to control the rotation angle and speed of the gimbal 120. In this way, the processing module 130 can control the gimbal 120 to perform directional adjustments based on the detection data from each crystal detector 110.

[0088] In some implementations, the gimbal 120 can support at least two rotation modes. The first is a continuous rotation mode, which can be used for rapid coarse orientation adjustments (e.g., the rotation speed can be set to 20° / s); the second is a step rotation mode, which can be used for fine orientation adjustments (e.g., each step rotation is set within the range of 0.1°-0.5°). Optionally, a higher rotation speed is used during coarse orientation, and a lower rotation speed and a smaller step angle are used during fine orientation to improve the final orientation locking accuracy.

[0089] Once the polycrystalline detector module is aligned with the target, the drive motor can maintain the current orientation to keep the detection center axis of the main crystal detector 111 stably pointing towards the radiation source.

[0090] 4. Structure of the processing module and display module

[0091] In this embodiment, the processing module 130 can adopt an embedded processor structure or other electronic processing units with data processing and control functions. The processing module 130 is connected to the polycrystalline detector module, the optical camera 140, the pan-tilt unit 120, and the display module 150, respectively, and is used to perform operations such as data acquisition, data storage, threshold calculation, deviation analysis, control calculation, image processing, and synchronous information display.

[0092] Specifically, the processing module 130 can receive detection data output by multiple crystal detectors 110, manage the background environment, and calculate the detection threshold of the radioactive source based on the background data; it can also compare and analyze the detection data of the main crystal detector 111 and the slave crystal detector 112 to determine the relative directional relationship of the radioactive source with respect to the detection center axis of the main crystal detector 111, and generate corresponding pan-tilt control commands.

[0093] The display module 150 may include a display screen, a touch screen, and related human-machine interface components. Optionally, the display module 150 may also be used in conjunction with physical buttons, a touch input unit, or other input devices to achieve mode switching, parameter setting, and function control. In some embodiments, the display module 150 may display at least one of the following information in real time: detection data from multiple crystal detectors 110, the current angle information of the pan-tilt unit 120, images captured by the optical camera 140, lock status information, and alarm information, etc. Furthermore, a mark, such as a crosshair, may be superimposed on the center of the displayed environmental image to indicate the image position corresponding to the detection center axis of the current main crystal detector 111, thereby facilitating the operator's observation and confirmation of the radiation source direction.

[0094] Based on the aforementioned radiation detection device 100, this embodiment of the invention also provides a method for locating and tracking a radiation source based on a pan-tilt unit (PTZ). This method can be applied to the aforementioned radiation detection device 100. Optionally, the method is mainly executed by the processing module 130 calling a preset program and coordinating with multiple crystal detectors 110, a pan-tilt unit 120, an optical camera 140, and a display module 150 to achieve the detection, orientation, locking, and continuous tracking of the radiation source. Please refer to [link to relevant documentation]. Figure 3 , Figure 3 This is a flowchart illustrating a method for locating and tracking a radiation source based on a gimbal, as provided in an embodiment of the present invention.

[0095] This method may include the following steps, which are described in turn below:

[0096] S301, when locating and tracking a radioactive source in the environment, acquire the detection data of the plurality of crystal detectors.

[0097] Specifically, the processing module 130 can acquire corresponding detection data from multiple crystal detectors 110 according to a preset sampling period.

[0098] The detection data may include crystal count rate, and may further include dose rate, energy spectrum information, or other data used to characterize the intensity of radiation response. In this embodiment, crystal count rate is mainly used as the basic data for direction determination and tracking control.

[0099] Optionally, the processing module 130 can synchronously acquire, cache, and time-align the detection data of multiple crystal detectors 110 to facilitate subsequent comparison analysis and control calculations.

[0100] S302, determine whether there is a radioactive source in the environment based on multiple detection data.

[0101] Specifically, the processing module 130 can determine whether the radiation response in the environment has reached the preset trigger condition based on the detection data currently output by the multiple crystal detectors 110; if the trigger condition is reached, it is determined that there is a radioactive source to be located and tracked in the environment, and enters the subsequent direction judgment and gimbal control process; if the trigger condition is not reached, the current monitoring state is maintained and the detection data acquisition continues.

[0102] In an optional embodiment, S302 includes: obtaining a dynamic tracking threshold for a radioactive source; obtaining the maximum detection data among a plurality of detection data; and determining whether a radioactive source exists in the environment based on the relationship between the maximum detection data and the dynamic tracking threshold for a radioactive source.

[0103] For example, in a five-crystal detector implementation, the processing module 130 can acquire the crystal count rates corresponding to the main crystal detector 111 and each slave crystal detector 112, and record the maximum value as Rmax, where Rmax = max(Rz+, Rx+, Rx-, Ry+, Ry-). Subsequently, Rmax is compared with a radioactive source dynamic tracking threshold. When Rmax is greater than or equal to the radioactive source dynamic tracking threshold, it can be determined that a radioactive source has been detected. Optionally, to reduce the probability of false triggering, a continuous multiple sampling confirmation mechanism can also be adopted. For example, only when three consecutive samples meet the above conditions is it determined that a radioactive source exists in the environment.

[0104] In other words, the processing module 130 can select the maximum detection data from the current detection data output by multiple crystal detectors 110, and compare the maximum detection data with a predetermined dynamic tracking threshold for radioactive sources. When the maximum detection data is greater than or equal to the dynamic tracking threshold for radioactive sources, it can be determined that a radioactive source exists in the environment; when the maximum detection data is less than the dynamic tracking threshold for radioactive sources, it can be determined that no radioactive source exists in the environment, or that the radioactive source has not yet entered the effective triggering range.

[0105] In this embodiment, the maximum detection data among multiple crystal detectors 110 is used as the triggering basis, which helps to more sensitively reflect whether the radiation source has entered the detection range and simplifies the system's judgment logic for entering the tracking mode.

[0106] The dynamic tracking threshold for the radioactive source is determined based on the background count rates of the multiple crystal detectors 110. Specifically, after the system starts up or before entering the working mode, the background of the current environment can be measured first to obtain the background count rates corresponding to each of the multiple crystal detectors 110; subsequently, the processing module 130 can determine the dynamic tracking threshold for the radioactive source based on the multiple background count rates.

[0107] Optionally, the maximum background count rate among multiple background count rates can be selected and combined with a preset multiplier to determine the dynamic tracking threshold of the radioactive source; alternatively, the average value, weighted value, or other statistical quantities that can characterize the environmental background level can be used to determine the dynamic tracking threshold of the radioactive source.

[0108] With the above settings, the dynamic tracking threshold of the radioactive source can be adaptively adjusted according to the current background radiation level of the environment, thereby reducing the risk of false alarms or missed alarms that may be caused by fixed thresholds under different environmental conditions, and improving the environmental adaptability and reliability of radioactive source detection and judgment.

[0109] S303, when it is determined that a radioactive source exists in the environment, the relative positional relationship between the radioactive source and the detection center axis of the main crystal detector is determined based on multiple detection data.

[0110] Specifically, the processing module 130 can determine the deflection trend and degree of deviation of the radiation source relative to the current detection direction of the main crystal detector 111 based on the differences between the detection data output by the multiple crystal detectors 110, thereby obtaining the relative directional relationship (i.e., the relative positional relationship) between the radiation source and the detection center axis of the main crystal detector 111.

[0111] Here, the relative directional relationship can be understood as: relative to the current detection center axis of the main crystal detector 111, in what deflection direction the radiation source is located, or what directional deviation exists between the radiation source direction and the current detection direction of the main crystal detector 111.

[0112] S304, drive the gimbal according to the relative position relationship so that the detection center axis of the main crystal detector points to the position of the radiation source.

[0113] Specifically, the processing module 130 can generate corresponding gimbal control commands based on the relative directional relationship determined in S303, and send the gimbal control commands to the gimbal 120 to control the gimbal 120 to drive the multiple crystal detectors 110 to rotate as a whole, so that the detection center axis of the main crystal detector 111 is adjusted to face the direction of the radiation source.

[0114] Optionally, this process (S304) can serve as a coarse orientation process to rapidly bring the main crystal detector 111 close to the approximate direction of the radiation source.

[0115] In a scenario where each group of slave crystal detectors 112 includes two crystal detectors 110 with collinear and oppositely pointing detection center axes, the straight lines corresponding to the detection center axes of different groups of slave crystal detectors 112 are different from each other, the detection center axes of all slave crystal detectors 112 are located in the same target plane, and the detection center axis of the main crystal detector 111 is perpendicular to the target plane, then step S303, "determining the relative directional relationship between the radiation source and the detection center axis of the main crystal detector 111 based on multiple detection data," may include the following steps 1.1-1.2:

[0116] Step 1.1: For each crystal detector, determine the detection vector of each crystal detector based on the detection center axis and the crystal count rate.

[0117] Step 1.2: Determine the relative positional relationship between the radiation source and the detection center axis of the main crystal detector based on the vector sum of all detection vectors.

[0118] Here, "detection vector" can be understood as: the directional representation formed by combining the detection intensity of the crystal detector 110 with the direction of its detection center axis, which is used to uniformly convert the detection results of multiple crystal detectors 110 into calculable directional information.

[0119] Step 1.1 can specifically be as follows: For each crystal detector 110, extract its current crystal count rate and determine the direction unit vector corresponding to the detection center axis of the crystal detector 110; subsequently, correlate the crystal count rate with the direction unit vector to obtain a detection vector characterizing the current response direction and response intensity of the crystal detector 110. Optionally, the magnitude of the detection vector is positively correlated with the crystal count rate, and the direction of the detection vector is consistent with the direction of the corresponding detection center axis.

[0120] Step 1.2 can be specifically as follows: the processing module 130 performs vector summation on the detection vectors corresponding to multiple crystal detectors 110 to obtain a composite direction vector; then, based on the directional deflection of the composite direction vector relative to the detection center axis of the main crystal detector 111, it determines the relative directional relationship between the radiation source and the detection center axis of the main crystal detector 111, and generates the coarse orientation control basis for the gimbal 120 accordingly.

[0121] It is understood that this method does not limit the structure of the multiple crystal detectors to the aforementioned five-crystal detectors. The multiple crystal detectors can have other shapes, such as seven-crystal, ring array, polyhedral distributed, or irregular spatial distributed structures, as long as the different crystal detectors have distinguishable detection center axis directions and can provide detection data reflecting the differences in radiation response in different directions. According to steps 1.1 and 1.2 above, this invention unifies and abstracts the detection intensity of each crystal detector and its respective detection center axis direction into a detection vector, and further obtains the overall direction estimation result through vector synthesis, thus supporting the realization of the functions of multiple crystal detectors with different shapes.

[0122] Through the above setup, a directional comparison relationship can be established among the same group of follower crystal detectors 112 to reflect the offset trend of the radiation source on the corresponding directional axis; different groups of follower crystal detectors 112 can jointly characterize the differences in radiation response in multiple directions. Furthermore, by summing the vectors of each detection vector, the approximate direction of the radiation source can be quickly obtained without full-angle mechanical scanning, thereby improving the efficiency and stability of direction determination.

[0123] Furthermore, when the plurality of slave crystal detectors 112 include a first slave crystal detector group and a second slave crystal detector group, the detection center axis of the first slave crystal detector group is perpendicular to the detection center axis of the second slave crystal detector group, the crystal size of each slave crystal detector 112 is consistent, and the crystal size of the master crystal detector 111 is larger than the crystal size of the slave crystal detector 112, step 1.1 may further include the following steps 1.11-1.12:

[0124] Step 1.11, for the crystal detector, determine the detection vector according to the following first formula:

[0125] Fi = Ri·ni;

[0126] Where Fi represents the detection vector of the i-th slave crystal detector among multiple slave crystal detectors, Ri represents the crystal count rate of the i-th slave crystal detector, and ni represents the unit vector corresponding to the detection center axis of the i-th slave crystal detector.

[0127] Step 1.12, for the main crystal detector, determine the detection vector according to the following second formula:

[0128] Fz = β·Rz·nz;

[0129] Where Fz represents the detection vector of the main crystal detector, Rz represents the crystal count rate of the main crystal detector, nz represents the unit vector corresponding to the detection center axis of the main crystal detector, and β represents the preset weighting coefficient.

[0130] Step 1.2, determining the relative positional relationship between the radiation source and the detection center axis of the main crystal detector based on the vector sum of all detection vectors, may further include the following steps 1.21-1.22:

[0131] Step 1.21: Summate all detection vectors to obtain the predicted direction of the radioactive source.

[0132] Step 1.22: Determine the predicted direction as the relative positional relationship between the radiation source and the detection center axis of the main crystal detector.

[0133] In the current method embodiment, the crystal count rate can be understood as the net count rate.

[0134] Here, "predicted direction" can be understood as the approximate direction of the radiation source calculated based on the current detection data of multiple crystal detectors 110, which can be used as the control basis for the coarse orientation of the gimbal 120.

[0135] With the above configuration, since the two sets of slave crystal detectors 112 are arranged in mutually perpendicular directions, the deflection of the radiation source relative to the master crystal detector 111 can be characterized in at least two orthogonal directions. Since the crystal size of each slave crystal detector 112 is consistent, the detection results between different slave crystal detectors 112 have good comparability. Since the crystal size of the master crystal detector 111 is large and a weighting coefficient β is introduced in the vector calculation, the detection sensitivity in the master direction can be improved while the accuracy of direction prediction can be taken into account.

[0136] In an optional embodiment, S304, after driving the gimbal according to the relative positional relationship to point the detection center axis of the main crystal detector to the position of the radiation source, the method further includes the following steps 2.1-2.4:

[0137] Step 2.1, determine the counting bias rate of each group from the crystal detector.

[0138] The count deviation rate represents the degree of deviation between the crystal count rates of the two slave crystal detectors in the same group. In other words, the "count deviation rate" can be understood as the degree of imbalance in the detection results between the two slave crystal detectors 112 in the same group. The smaller the value, the closer the current detection direction of the master crystal detector 111 is to the direction of the radiation source.

[0139] Step 2.2: Determine whether each counting deviation rate meets the locking condition.

[0140] The locking condition includes a counting deviation rate that is less than a preset deviation threshold.

[0141] Step 2.3: If each count deviation rate meets the locking condition and the crystal count rate of the main crystal detector is the maximum count rate, then the radiation source is determined to be locked.

[0142] Step 2.4: If there is a count deviation rate that does not meet the locking condition or the crystal count rate of the master crystal detector is not the maximum count rate, then perform a fine orientation process to reduce the count deviation rate of the slave crystal detector group that does not meet the locking condition, and return to step 2.1.

[0143] Specifically, in the implementation of the five-crystal detector, the counting deviation rate can be calculated separately for the first slave crystal detector group and the second slave crystal detector group. For example, the counting deviation rate corresponding to the first slave crystal detector group can be expressed as δx=|Rx+-Rx-| / max(Rx+,Rx-)×100%, and the counting deviation rate corresponding to the second slave crystal detector group can be expressed as δy=|Ry+-Ry-| / max(Ry+,Ry-)×100%.

[0144] The processing module 130 can compare the count deviation rate of each group with a preset deviation threshold, for example, the preset deviation threshold can be 3%. When δx and δy are both less than or equal to the preset deviation threshold, and the crystal count rate of the main crystal detector 111 is the highest among the multiple crystal detectors 110, it can be determined that the main crystal detector 111 has locked the direction of the radiation source; otherwise, it is considered that there is still a directional deviation, and fine orientation adjustment needs to be performed.

[0145] With the above settings, the counting deviation rate of each group of slave crystal detectors 112 characterizes the degree of deviation of the current pointing direction of the master crystal detector 111 relative to the radiation source direction. Combined with the condition that the crystal counting rate of the master crystal detector 111 is at its maximum, a composite locking criterion can be formed. Compared with judging solely based on a single maximum counting rate or solely based on symmetry conditions, this composite locking method is more conducive to accurately determining whether the master crystal detector 111 is truly aligned with the radiation source direction, thereby improving locking accuracy and reducing the probability of false locking.

[0146] The fine orientation process may include the following steps 3.1-3.3:

[0147] Step 3.1: Obtain the relationship between the count rates of the two crystals in the slave crystal detector group that do not meet the locking condition.

[0148] Step 3.2: Among the slave crystal detector groups that do not meet the locking condition, determine the crystal detector with the larger crystal count rate according to the size relationship.

[0149] Step 3.3: Drive the gimbal to adjust the detection center axis of the main crystal detector so that the detection center axis of the main crystal detector deflects toward the detection center axis of the crystal detector with a larger crystal count rate, so as to reduce the count deviation rate of the slave crystal detector group that does not meet the locking condition.

[0150] Specifically, when the counting deviation rate of a certain group of slave crystal detectors is greater than a preset deviation threshold, the processing module 130 first compares the crystal counting rates of the two slave crystal detectors in the group to determine the side with the larger crystal counting rate; then, it controls the pan-tilt unit 120 to deflect towards the detection center axis direction corresponding to the slave crystal detector with the larger crystal counting rate at a small step angle or a low rotation speed; after each deflection, it re-acquires the detection data of multiple crystal detectors 110 and recalculates the corresponding counting deviation rate until the counting deviation rate of the group meets the locking condition or reaches the preset stop condition.

[0151] Optionally, the preset stopping conditions may include reaching a preset number of adjustments, reaching a preset adjustment duration, or the system switching to manual intervention mode.

[0152] In other words, when there is a significant difference in the count rates of the two slave crystal detectors 112 in the same group, the processing module 130 can determine the adjustment direction of fine orientation based on the relationship between the two, and control the pan-tilt unit 120 to make small-angle adjustments so that the responses of the two slave crystal detectors 112 in the same group gradually tend to be balanced, thereby causing the detection center axis of the master crystal detector 111 to be closer to the direction of the radiation source. Through the above fine orientation process, it is beneficial to reduce the direction error in the locking process, shorten the convergence time, and improve the stability of fine orientation control.

[0153] In an optional embodiment, the method further includes steps 4.1-4.2:

[0154] Step 4.1: During the process of driving the gimbal according to the relative position relationship, the rotation speed of the gimbal is set to a first rotation speed.

[0155] Step 4.2, during the fine orientation process, the rotation speed of the gimbal is set to a second rotation speed; wherein the first rotation speed is greater than the second rotation speed.

[0156] For example, in the coarse orientation stage, the processing module 130 can set the gimbal 120 to a continuous rotation mode and use a relatively large first rotation speed to make the main crystal detector 111 quickly approach the approximate direction of the radiation source; in the fine orientation stage, the processing module 130 can set the gimbal 120 to a step rotation mode and use a relatively small second rotation speed and a small step angle to make smoother and finer adjustments when approaching the direction of the radiation source.

[0157] Optionally, the first rotation speed can be set according to the coarse orientation response requirements, and the second rotation speed can be set according to the locking accuracy requirements.

[0158] With the above settings, using a larger rotation speed in the coarse orientation stage is beneficial for quickly turning the main crystal detector 111 to the approximate direction of the radiation source; using a smaller rotation speed in the fine orientation stage is beneficial for reducing the risk of overshoot and oscillation, improving the smoothness of the orientation process and the final locking accuracy, thereby taking into account both the system's response speed and adjustment accuracy.

[0159] In an optional embodiment, after S304, the method may further include the following steps 5.1-5.2:

[0160] Step 5.1: Use the processing module to drive the display module to display the environmental image captured by the optical camera on the display module.

[0161] Step 5.2: Display a radiation source locking marker on the environmental image. The radiation source locking marker corresponds to the position pointed to by the optical axis of the optical camera.

[0162] For example, the processing module 130 can receive environmental image data collected by the optical camera 140 in real time and control the display module 150 to display the corresponding image; when the system is in coarse orientation, fine orientation or locked state, the processing module 130 can also overlay and display a locking mark corresponding to the optical axis direction of the optical camera 140 on the environmental image, such as a crosshair, a center indicator, a circular target or other graphic mark.

[0163] Optionally, information such as the pan-tilt angle, crystal count rate of the main crystal detector 111, dose rate, lock status, and alarm level can also be synchronously overlaid on the environmental image.

[0164] Specifically, when the main crystal detector 111 is aligned with the direction of the radiation source, since the optical axis of the optical camera 140 is coaxially aligned with the detection center axis of the main crystal detector 111, the central area in the environmental image acquired by the optical camera 140 corresponds to the direction of the radiation source. At this time, radiation source locking marks, such as crosshairs, center markers, or other visual cues, can be superimposed on the environmental image to convert the radiation direction information into an intuitive image location cue, making it easier for operators to confirm the direction of the radiation source and its surrounding environment.

[0165] Based on the above method embodiments, the following describes the above method in further detail using a five-crystal detector implementation as an example.

[0166] 1. System startup, initialization, and background measurement

[0167] Please refer to Figure 4 In this embodiment, after the radiation detection device 100 is powered on, the processing module 130 first executes a self-test program to check whether the polycrystalline detector module, the pan-tilt unit 120, the optical camera 140, and the display module 150 are in normal working condition. After the self-test passes, the processing module 130 controls the pan-tilt unit 120 to reset to its initial position.

[0168] For example, the pan-tilt unit 120 can be reset to a position with a horizontal angle of 0° and a pitch angle of 0°, so that the main crystal detector 111 faces a preset forward direction. At this time, the display module 150 can output a system ready prompt message to prompt the operator to perform a background measurement.

[0169] After the operator confirms that there is no radioactive source to be detected in the current environment, the background measurement operation can be triggered through the display module 150 or other input units. The processing module 130 controls multiple crystal detectors 110 to continuously collect detection data within a preset time period, such as continuously collecting crystal count rate data for 30 to 60 seconds. Subsequently, the processing module 130 can perform statistical processing on the collected data, such as removing outliers and calculating time averages, thereby obtaining the background count rates corresponding to the main crystal detector 111 and each slave crystal detector 112.

[0170] For example, in a five-crystal detector structure, the background count rates of the main crystal detector 111 and the four slave crystal detectors 112 located in the X+, X-, Y+, and Y- axes can be obtained, denoted as Rz+_bg, Rx+_bg, Rx-_bg, Ry+_bg, and Ry-_bg, respectively. The processing module 130 can further determine the dynamic tracking threshold based on the background count rates. Optionally, the maximum value Rmax_bg among the multiple background count rates can be taken first, and then the dynamic tracking threshold can be determined according to a preset multiplier K, as shown in the following example:

[0171] Threshold = Rmax_bg × K

[0172] The multiplier K can be set according to the actual usage environment, equipment sensitivity requirements, or experimental calibration results.

[0173] After the baseline measurement is completed, the processing module 130 can store the baseline data and corresponding thresholds, and control the display module 150 to output a baseline measurement completion prompt message, so that the system enters the monitoring mode.

[0174] 2. Monitoring modes and automatic detection of radioactive sources

[0175] In the monitoring mode, the processing module 130 continuously acquires detection data from the five crystal detectors 110 at a preset sampling frequency. For example, the sampling frequency can be set to 10 Hz. The processing module 130 can determine the maximum count rate Rmax among the five crystal detectors 110 based on their current crystal count rates. Taking a five-crystal detector structure as an example, the maximum count rate can be expressed as:

[0176] Rmax = max(Rz+, Rx+, Rx-, Ry+, Ry-)

[0177] Wherein, Rz+ represents the current crystal count rate of the master crystal detector 111, and Rx+, Rx-, Ry+ and Ry- represent the current crystal count rates of the four slave crystal detectors 112, respectively.

[0178] During monitoring, the display module 150 can display real-time information such as the detection data of each crystal detector 110, environmental images captured by the optical camera 140, dynamic tracking thresholds, and the current system status. At this time, the pan-tilt unit 120 can remain stationary, and the system remains in a state of waiting for the radiation source to enter the effective detection range.

[0179] When the processing module 130 determines that the maximum count rate Rmax exceeds the dynamic tracking threshold, it can preliminarily determine that a radioactive source has been detected. To reduce the probability of false positives, a continuous multiple sampling confirmation mechanism can be further adopted. For example, it can be required that Rmax exceeds the dynamic tracking threshold in three consecutive samples before the presence of a radioactive source in the environment is confirmed. After confirmation, the processing module 130 can control the device to issue an alarm prompt and automatically switch to tracking mode to enter the subsequent direction determination and pan-tilt control process.

[0180] 3. Initial orientation process (i.e., coarse orientation)

[0181] After detecting a radioactive source, the processing module 130 may first perform an initial orientation process to quickly orient the main crystal detector 111 toward the approximate direction of the radioactive source. This process can serve as a coarse orientation process.

[0182] In this embodiment, a direction estimation model can be constructed using the spatial distribution characteristics of the net count rate of multiple crystal detectors 110. The "net count rate" can be understood as the result of subtracting the corresponding background count rate from the current crystal count rate, which is used to reduce the influence of ambient background radiation on direction determination.

[0183] Furthermore, the net count rate of multiple crystal detectors 110 can be combined with the direction of their detection center axis to construct a detection vector characterizing the direction of the radiation source, and the predicted direction of the radiation source can be obtained through vector synthesis.

[0184] Specifically, for each crystal detector 112, the detection vector can be determined as follows:

[0185] Fi = Ri·ni where Fi represents the detection vector corresponding to the i-th crystal detector 112, Ri represents the net count rate of the i-th crystal detector 112, and ni represents the unit vector corresponding to the detection center axis of the i-th crystal detector 112, i ∈ {x+,x-,y+,y-}.

[0186] For the main crystal detector 111, the detection vector can be determined as follows:

[0187] Fz = β·Rz·nz

[0188] Wherein, Fz represents the detection vector corresponding to the main crystal detector 111, Rz represents the net count rate of the main crystal detector 111, nz represents the unit vector corresponding to the detection center axis of the main crystal detector 111, and β represents the preset weighting coefficient. The preset weighting coefficient β can be set according to the size difference, sensitivity difference, experimental calibration results, or simulation results between the main crystal detector 111 and the slave crystal detector 112.

[0189] In the five-crystal detector structure, the processing module 130 can perform vector summation on all detection vectors to obtain the radiation source direction prediction vector S. For example, it can be expressed as:

[0190] S = Fx+ + Fx- + Fy+ + Fy- + Fz

[0191] Wherein, Fx+, Fx-, Fy+, and Fy- represent the detection vectors corresponding to the crystal detector 112. It should be noted that since the unit vectors themselves already reflect the pointing relationship of different detection center axes, the vector summation can be directly performed based on the direction attributes of each unit vector.

[0192] Subsequently, the processing module 130 can determine the directional parameters for controlling the rotation of the gimbal 120 based on the radiation source direction prediction vector S. For example, the prediction vector can be converted into corresponding azimuth and pitch control values ​​to generate the initial turning command for the gimbal 120.

[0193] For example, horizontal angle: φ = arctan(Sy / Sx); pitch angle: θ = arccos(Sz / |S|).

[0194] The above method allows for the rapid acquisition of the approximate orientation of the radiation source without the need for full-angle mechanical scanning, thus improving initial orientation efficiency.

[0195] In some implementations, after initial orientation, the detection center axis of the main crystal detector 111 can be basically oriented toward the direction of the radiation source, but there may still be a certain angular deviation, so a fine orientation process can be further performed subsequently.

[0196] 4. Fine-grained directional control process

[0197] After the initial orientation is completed, the processing module 130 can further perform a fine orientation control process to improve the accuracy of the main crystal detector 111 in aligning with the direction of the radiation source.

[0198] Please refer to Figure 5 In this embodiment, provided that the crystal count rate of the main crystal detector 111 is the larger or maximum value among the multiple crystal detectors 110, the processing module 130 can continue to acquire the detection data of each slave crystal detector 112 and calculate the count deviation rate of each group of slave crystal detectors 112. The "count deviation rate" is used to characterize the degree of imbalance between the detection results of two slave crystal detectors 112 in the same group. The smaller the value, the closer the current detection direction of the main crystal detector 111 is to the direction of the radiation source.

[0199] Taking two sets of crystal detectors 112 corresponding to the first and second directions respectively as an example, the counting deviation rate δx in the first direction and the counting deviation rate δy in the second direction can be calculated respectively. An example is as follows:

[0200] δx = |Rx+ - Rx-| / max(Rx+, Rx-) × 100%

[0201] δy = |Ry+ - Ry-| / max(Ry+, Ry-) × 100%

[0202] Wherein, Rx+ and Rx- represent the first group of crystal count rates from crystal detector 112, and Ry+ and Ry- represent the second group of crystal count rates from crystal detector 112.

[0203] When δx or δy is greater than a preset deviation threshold, it indicates that the current pointing of the main crystal detector 111 is still deviated, and the processing module 130 can control the pan-tilt unit 120 to perform fine orientation adjustment. Specifically, the processing module 130 can determine the direction to be adjusted based on the crystal count rate pattern of the two slave crystal detectors 112 in the same group, and drive the pan-tilt unit 120 to deflect the main crystal detector 111 in a direction that is conducive to reducing the count deviation rate of the group.

[0204] For example, if δx > 3%, the gimbal is driven to rotate in a smaller direction based on the relationship between Rx+ and Rx-; if δy > 3%, the gimbal is driven to rotate in a smaller direction until δx ≤ 3% and δy ≤ 3%. Fine-tuning uses a step mode (0.1°-0.5° per step, speed 0.5° / s). After adjustment, wait 100ms and re-acquire data to form closed-loop control.

[0205] In some implementations, the fine orientation process can employ step control. For example, the gimbal 120 can be adjusted with a small step angle, ranging from 0.1° to 0.5°; simultaneously, the rotation speed during fine orientation can be lower than the rotation speed during the initial orientation process to improve adjustment smoothness and convergence accuracy. After each adjustment, the processing module 130 can wait for a preset time, such as 100 ms, to reacquire the detection data from the five crystal detectors 110 and recalculate the counting deviation rate for each group, thereby forming closed-loop control.

[0206] 5. Determination and Confirmation of Radiation Lock-in Conditions

[0207] After each adjustment of the gimbal 120, the processing module 130 can determine whether the current conditions for locking the radioactive source are met.

[0208] In this embodiment, the locking conditions may include at least the following three items: the crystal count rate of the main crystal detector 111 is the highest among the multiple crystal detectors 110; the count deviation rate in the first direction meets the preset deviation threshold requirement, for example, δx is less than or equal to 3%; the count deviation rate in the second direction meets the preset deviation threshold requirement, for example, δy is less than or equal to 3%.

[0209] When the above conditions are met simultaneously, the processing module 130 can determine that the detection center axis of the main crystal detector 111 has locked onto the direction of the radiation source. At this time, the processing module 130 can record the detection data, gimbal angle information and time information corresponding to the locking moment, and control the display module 150 to output a locking success prompt message, and then enter the continuous tracking state.

[0210] If any of the above locking conditions are not met, the processing module 130 may continue to return to the fine-direction process until the locking conditions are met.

[0211] In some implementations, a lock timeout mechanism can also be set. For example, if the lock conditions are not met within a preset time range, the processing module 130 can output a lock failure message and switch to manual intervention mode or re-execute the orientation process to improve the flexibility of system use.

[0212] 6. Continuous tracking, dynamic adjustment, and visual instruction output.

[0213] After the radiation source is locked, the system enters a continuous tracking state. In this state, the processing module 130 can continuously perform the following functions.

[0214] 6.1 Continuous monitoring

[0215] The processing module 130 continues to acquire detection data from multiple crystal detectors 110 according to a preset sampling frequency, and calculates the counting deviation rate of each group from the crystal detectors 112 in real time to monitor whether the direction of the radiation source has changed.

[0216] 6.2 Dynamic Adjustment

[0217] When the processing module 130 determines that the counting deviation rate in any direction exceeds the preset deviation threshold again, it can be considered that the direction of the radiation source has changed relative to the current detection direction. At this time, the processing module 130 can execute the fine orientation process again, controlling the gimbal 120 to make a small angle adjustment so that the main crystal detector 111 is re-aligned with the direction of the radiation source. If all locking conditions are continuously met, the gimbal 120 can maintain its current attitude. Through the above closed-loop feedback mechanism, continuous automatic tracking of the moving radiation source can be achieved.

[0218] 6.3 Visual Indication Output

[0219] Since the optical axis of the optical camera 140 is coaxially aligned with the detection center axis of the main crystal detector 111, when the main crystal detector 111 locks onto the direction of the radiation source, the central area of ​​the environmental image captured by the optical camera 140 corresponds to the direction of the radiation source. Based on this, the processing module 130 can control the display module 150 to display the environmental image in real time and overlay visual cues, such as crosshairs, center marks, or other locking indicators, onto the image. Simultaneously, information such as the pan-tilt angle, detection data, dose rate, or alarm status can also be overlaid and displayed, making it easier for operators to intuitively confirm the direction of the radiation source and its surrounding environment.

[0220] 6.4 Data Logging and Alarms

[0221] During continuous tracking, the processing module 130 can also record detection data and operational status data. For example, it can record information such as the crystal count rate, dose rate, pan-tilt angle, timestamp, and lock status of multiple crystal detectors 110 at preset time intervals; simultaneously, it can save environmental images at preset time intervals. Furthermore, it can set multiple alarm thresholds (e.g., 1, 2.5, 10 μSv / h) based on the dose rate, and output corresponding level of audible and visual alarm information when the corresponding threshold is triggered to prompt operators to take appropriate protective measures.

[0222] 7. Summary of Methods and Procedures

[0223] Through the above implementation methods, the PTZ-based radioactive source positioning and tracking method provided in this invention may include the following process: First, perform system self-test, initialization, and background measurement; then, automatically detect whether the radioactive source has entered the detection range in the monitoring mode; after detecting the radioactive source, determine the relative directional relationship between the radioactive source and the main crystal detector 111 through the detection data of multiple crystal detectors 110, and control the PTZ 120 to perform initial orientation; based on this, perform fine orientation and lock judgment by calculating the counting deviation rate of each group of slave crystal detectors 112; after locking is completed, perform continuous tracking, visual indication output, alarm, and data recording operations through a closed-loop feedback mechanism.

[0224] Therefore, the embodiments of the present invention can realize a complete closed-loop control process from radioactive source detection, direction determination, automatic orientation, lock confirmation to continuous tracking, and can improve the visualization of radioactive source direction information through optical image output. It is suitable for radioactive source search, radiation emergency response and other application scenarios that require radioactive source direction positioning and dynamic tracking.

[0225] Based on the above embodiments, it can be understood that:

[0226] The method and apparatus of this application, by setting up multiple crystal detectors with different detection center axis directions and combining them with a pan-tilt control, locking judgment, and image display mechanism, realize automatic detection, direction determination, orientation locking, and continuous tracking of a radioactive source. Specifically, multiple crystal detectors are used to provide radiation response information in different directions. The processing module determines the relative position of the radioactive source with respect to the detection center axis of the main crystal detector based on the detection data of each crystal detector and controls the pan-tilt to adjust the direction. On this basis, the current pointing state is locked by judging the counting deviation rate between each group of secondary crystal detectors and whether the main crystal detector has the maximum counting rate. After the locking condition is met, the direction information of the radioactive source is displayed as an image by an optical camera coaxially aligned with the detection center axis of the main crystal detector. Furthermore, by synthesizing the direction vector based on the multi-crystal detection data, the approximate direction of the radioactive source can be quickly determined without full-angle scanning. The closed-loop control method combining coarse and fine orientation can improve the efficiency and accuracy of radioactive source orientation and locking. By continuously monitoring the change in the counting deviation rate, dynamic tracking of moving radioactive sources can also be achieved. Therefore, the methods and equipment of this application are applicable to scenarios such as radioactive source search, nuclear safety emergency response, environmental radiation monitoring, and border nuclear material inspection.

[0227] The embodiments provided by this invention achieve omnidirectional visual positioning and dynamic tracking of radiation sources through the linkage of cameras, multi-detector arrays, and gimbals. Like an intelligent camera equipped with a "radiation radar + automatic tracking gimbal," it can not only automatically locate the source but also visually display its position on the screen; the image rotates as the source moves. Utilizing the spatial distribution characteristics of the net count rate of each crystal, a virtual force field model is constructed, and the optimal pointing direction is directly calculated through vector synthesis, achieving one-step orientation without requiring full-field rotation scanning.

[0228] Significantly improved cost-effectiveness: The simplified solution of five crystal detectors + two-dimensional gimbal reduces costs by more than 70% compared to high-end systems such as Compton cameras and coded aperture imaging, while achieving the same level of positioning accuracy (≤2°), realizing a breakthrough in low cost and high performance.

[0229] Balancing sensitivity and directionality: The innovative asymmetric crystal layout, with the Z+ axis main crystal having a detection area 2-3 times that of the auxiliary crystals, improves the main direction detection sensitivity by more than 100%. At the same time, it achieves accurate direction determination through four auxiliary crystals, solving the dilemma of traditional technology.

[0230] Outstanding dynamic tracking capability: Through the intelligent fusion of mechanical motion and radiation detection, it achieves automatic and continuous tracking of mobile radioactive sources with a tracking response time of <2 seconds and an angle tracking error of ≤1°, which can effectively cope with dynamic scenarios such as radioactive source escape and vehicle transportation.

[0231] Intuitive and easy to operate: The optical camera and detector are designed to be coaxial, which transforms the abstract radiation direction into a visual image. Operators can quickly understand the location of the radiation source without professional training, making it particularly suitable for emergency response scenarios.

[0232] High system reliability: Adopting mature scintillation crystal detector technology and industrial-grade gimbal mechanical structure, the system has good stability and simple maintenance. It can work stably in an ambient temperature range of -20℃ to +50℃, making it suitable for field and complex environment applications.

[0233] Highly scalable: The system has reserved data interfaces, which can be integrated with GPS positioning and wireless communication modules to realize remote real-time reporting of the location of radiation sources; it can also be mounted on mobile platforms such as unmanned vehicles and drones to expand application scenarios.

[0234] In summary, this application has the following beneficial effects:

[0235] 1. Low cost and simple structure: Compared to complex systems such as Compton cameras and coded aperture imaging, the cost is reduced by more than 70%, eliminating the need for complex X-ray imaging algorithms and expensive multi-layer detector arrays; 2. Balanced sensitivity and directionality: The asymmetric crystal layout improves the main direction detection sensitivity by more than 100%, while the auxiliary crystal enables accurate direction determination; 3. High positioning accuracy: Positioning accuracy ≤2°, dual criteria (maximum count rate + consistent symmetry) ensure locking accuracy; 4. Strong dynamic tracking capability: Automatic closed-loop control enables real-time tracking of moving radiation sources, with a tracking response time of <2 seconds; 5. Intuitive operation: Optical visual synchronous indication transforms the abstract radiation direction into a visual image, allowing for use without professional training; 6. High reliability and strong scalability: Utilizing mature technology, the system is stable and can be integrated with GPS and communication modules, making it suitable for various application scenarios such as drone and machine-borne applications.

[0236] In order to perform the corresponding steps in the above embodiments and their various alternative methods, this application also provides a radiation source positioning and tracking control module, which can be set in the processing module 130 to acquire detection data of multiple crystal detectors 110 and control the gimbal 120 based on the detection data, thereby realizing the above method embodiments.

[0237] The following describes an implementation method for a radiation source location and tracking control module. Please refer to [link / reference]. Figure 6 , Figure 6 This diagram illustrates a functional block diagram of a radiation source positioning and tracking control module 500 provided in an embodiment of the present invention. The radiation source positioning and tracking control module 500 can be used to implement all or part of the steps in the aforementioned method embodiments. It should be noted that the basic principle and technical effects of the radiation source positioning and tracking control module 500 provided in this embodiment are the same as those in the aforementioned method embodiments. To avoid repetition, for content not described in detail in this embodiment, please refer to the relevant descriptions in the aforementioned method embodiments.

[0238] In an optional embodiment, the radiation source positioning and tracking control module 500 may include a transceiver unit 510 and a processing unit 520.

[0239] The transceiver unit 510 is used to receive detection data output by multiple crystal detectors 110 and can send control commands or data to the pan-tilt unit 120, display module 150 and other related functional modules. The processing unit 520 is used to process the detection data of multiple crystal detectors 110 to determine whether there is a radioactive source in the environment, determine the relative position of the radioactive source with respect to the detection center axis of the main crystal detector, and generate corresponding pan-tilt control commands to realize coarse orientation, fine orientation, locking judgment and continuous tracking of the radioactive source.

[0240] Optionally, the transceiver unit 510 and the processing unit 520 described above can be implemented in the form of software, firmware, or hardware. For example, the transceiver unit 510 and the processing unit 520 can be stored in the memory of the processing module 130 as program instructions and executed by the processor in the processing module 130; or, the transceiver unit 510 and the processing unit 520 can be partially or wholly embedded in the processing module 130.

[0241] It is understood that the transceiver unit 510 and the processing unit 520 can be used to support the radiation source positioning and tracking control module 500 in executing the relevant steps in the foregoing method embodiments, as well as to implement other related processing procedures described herein. This application does not limit this application.

[0242] Based on the above method embodiments, this invention also provides a computer-readable storage medium storing a computer program. When a processor runs the computer program, it can execute the above method embodiments. Specifically, the storage medium can be a general-purpose storage medium, such as a memory module, SSD, or external hard drive. When the computer program on the storage medium is run, it can execute the methods described in the above embodiments to achieve the corresponding technical objectives.

[0243] The above are merely embodiments of the present invention and are not intended to limit the scope of protection of the present invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for locating and tracking a radiation source based on a gimbal, characterized in that, This invention is applied to radiation detection equipment, which includes multiple crystal detectors and a pan-tilt unit. The multiple crystal detectors are mounted on the pan-tilt unit. The multiple crystal detectors include a master crystal detector and multiple sets of slave crystal detectors. The detection center axes of any two crystal detectors are in different directions. Each set of slave crystal detectors includes two crystal detectors whose detection center axes are located on the same straight line but in opposite directions. The detection center axes of different sets of slave crystal detectors are located on different straight lines. The detection center axes of all slave crystal detectors are located on the same target plane. The detection center axis of the master crystal detector is perpendicular to the target plane. The method includes the following steps: When locating and tracking radioactive sources in the environment, the detection data of the multiple crystal detectors are acquired; Determine whether a radioactive source exists in the environment based on multiple detection data; When it is determined that a radioactive source exists in the environment, the relative positional relationship between the radioactive source and the detection center axis of the main crystal detector is determined based on multiple detection data. The gimbal is driven according to the relative positional relationship so that the detection center axis of the main crystal detector points to the position of the radiation source; Determining the relative positional relationship between the radiation source and the detection center axis of the main crystal detector based on multiple detection data includes: For each crystal detector, the detection vector of each crystal detector is determined based on the detection center axis and the crystal count rate. The relative positional relationship between the radiation source and the detection center axis of the main crystal detector is determined based on the vector sum of all detection vectors.

2. The method according to claim 1, characterized in that, The multiple sets of slave crystal detectors include a first slave crystal detector group and a second slave crystal detector group. The detection center axis of the first slave crystal detector group is perpendicular to the detection center axis of the second slave crystal detector group. The crystal sizes of the slave crystal detectors are consistent. For each crystal detector, the detection vector of each crystal detector is determined based on the detector's detection center axis and crystal count rate, including: For a crystal detector, the detection vector is determined according to the following first formula: Fi = Ri·ni; where Fi represents the detection vector of the i-th slave crystal detector among multiple slave crystal detectors, Ri represents the crystal count rate of the i-th slave crystal detector, and ni represents the unit vector corresponding to the detection center axis of the i-th slave crystal detector. For the primary crystal detector, the detection vector is determined according to the following second formula: Fz = β·Rz·nz; where Fz represents the detection vector of the main crystal detector, Rz represents the crystal count rate of the main crystal detector, nz represents the unit vector corresponding to the detection center axis of the main crystal detector, and β represents the preset weighting coefficient. The relative positional relationship between the radiation source and the detection center axis of the main crystal detector is determined based on the vector sum of all detection vectors, including: The predicted direction of the radiation source is obtained by summing all the detection vectors. The predicted direction is defined as the relative positional relationship between the radiation source and the detection center axis of the main crystal detector.

3. The method according to claim 1, characterized in that, After the step of driving the gimbal according to the relative positional relationship so that the detection center axis of the main crystal detector points to the position of the radiation source, the method further includes: Determine the counting deviation rate for each group of slave crystal detectors; wherein the counting deviation rate represents the degree of deviation between the crystal counting rates of two slave crystal detectors in the same group; Determine whether each count deviation rate meets the locking condition; wherein, the locking condition includes a count deviation rate being less than a preset deviation threshold; If each count deviation rate meets the locking condition and the crystal count rate of the main crystal detector is the maximum count rate, then the radiation source is determined to be locked. If a count deviation rate does not meet the locking condition or the crystal count rate of the master crystal detector is not the maximum count rate, a fine orientation process is performed to reduce the count deviation rate of the slave crystal detector group that does not meet the locking condition, and the process returns to the step of determining the count deviation rate of each slave crystal detector group.

4. The method according to claim 3, characterized in that, The fine orientation process includes the following steps: Obtain the relationship between the count rates of two crystals in a slave crystal detector group that do not meet the locking condition; Among the slave crystal detector groups that do not meet the locking condition, the crystal detector with the larger crystal count rate is determined according to the size relationship. The gimbal is driven to adjust the detection center axis of the main crystal detector so that the detection center axis of the main crystal detector deflects toward the detection center axis of the crystal detector with a larger crystal count rate, thereby reducing the count deviation rate of the slave crystal detector group that does not meet the locking condition.

5. The method according to claim 3, characterized in that, The method further includes: During the process of driving the gimbal according to the relative positional relationship, the rotation speed of the gimbal is set to a first rotation speed; During the fine orientation process, the rotation speed of the gimbal is set to a second rotation speed; wherein the first rotation speed is greater than the second rotation speed.

6. The method according to claim 1, characterized in that, Determining the presence of radioactive sources in the environment based on multiple detection data includes: Obtain the dynamic tracking threshold of the radioactive source; Obtain the maximum detection data among the multiple detection data; The presence of a radioactive source in the environment is determined based on the relationship between the maximum detection data and the dynamic tracking threshold of the radioactive source.

7. The method according to claim 6, characterized in that, The dynamic tracking threshold for the radioactive source is determined based on the background count rate of the multiple crystal detectors.

8. The method according to any one of claims 1-7, characterized in that, The radiation detection device also includes an optical camera, a processing module, and a display module. Each crystal detector is electrically connected to the processing module. The optical camera and the display module are both electrically connected to the processing module. The optical camera is mounted on the main crystal detector, and the optical axis of the optical camera is coaxially aligned with the detection center axis of the main crystal detector. After the step of driving the gimbal according to the relative positional relationship so that the detection center axis of the main crystal detector points to the position of the radiation source, the method further includes: The processing module drives the display module to display the environmental image captured by the optical camera on the display module; A radiation source locking mark is displayed on the environmental image; wherein the radiation source locking mark corresponds to the position pointed to by the optical axis of the optical camera.

9. A radiation detection device, characterized in that, include: The system includes multiple crystal detectors, a gimbal, and a processing module. The multiple crystal detectors and the gimbal are electrically connected to the processing module. The multiple crystal detectors are mounted on the gimbal. The multiple crystal detectors include a master crystal detector and multiple sets of slave crystal detectors. The directions of the detection center axes of any two crystal detectors are different. The processing module is used to control the plurality of crystal detectors and the gimbal to implement the method as described in any one of claims 1 to 8.

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