A positioning system and positioning method for radiotherapy beam alignment

Abstract

The application provides a kind of radiotherapy beam flow alignment fixed positioning system, comprising: bearing device, positioning movement device, positioning guide device and control device;Bearing device is used to bear patient;Positioning movement device is connected with bearing device, for adjusting the position and inclination angle of bearing device;Positioning guide device includes reference positioning unit, positioning registration unit and real-time verification unit;Reference positioning unit is used to provide space reference;Positioning registration unit is used to acquire image data to obtain the difference between the actual position and planned position of patient target area;Real-time verification unit is used to continuously monitor the body surface displacement of patient during treatment;Control system is based on treatment plan and the data of positioning guide device, controls the position and inclination angle of bearing device adjusted by positioning movement device;It can realize six-dimensional accurate positioning, reduce target area position deviation, automatic positioning process to shorten time, enhance safety protection, and provide whole course of treatment without radiation continuous monitoring.

Description

Technical Field

[0001] This application relates to the field of boron neutron capture therapy, specifically to a positioning system and method for aligning and fixing a radiotherapy beam. Background Technology

[0002] Boron neutron capture therapy (BNCT), a targeted radiotherapy that relies on a fixed-direction neutron beam to react nuclearly with boron-10 isotopes within the tumor, is highly dependent on the precise localization of the patient's target area for its therapeutic efficacy. In clinical practice, the patient must be precisely positioned along the neutron beam path, often requiring non-standard positions such as sitting or at large angles to match the beam's direction of incidence.

[0003] However, existing technologies have significant shortcomings in patient positioning for BNCT. Traditional multi-degree-of-freedom treatment bed systems are primarily derived from photon or proton radiotherapy environments, and their design revolves around a central point such as a rotating gantry. The movement of the bed plate is limited to linear translation and a limited number of rotational degrees of freedom within a plane. Therefore, such systems cannot achieve arbitrary spatial attitude adjustments around a fixed neutron beam aperture, resulting in insufficient six-dimensional positioning accuracy in complex positions. Furthermore, during long-stroke movements, the distal end of the bed plate is prone to elastic deformation, further exacerbating target area position deviations.

[0004] The system's patient placement process is highly dependent on manual intervention, involving the sequential execution of multiple independent steps such as treatment bed operation, image verification, and body surface monitoring. The procedures are cumbersome and time-consuming, making it difficult to meet the stringent time window requirements for boron drug metabolism in BNCT. Safety mechanisms are particularly weak, relying solely on passive measures such as physical limit switches, emergency stop buttons, and motor overload detection. These measures cannot anticipate potential collision risks in complex paths and confined spaces during the high-speed, high-load movement of the robotic arm. Especially when the robotic arm carrying the patient approaches fixed beam apertures, imaging equipment, or surrounding obstacles, it lacks real-time monitoring and autonomous avoidance capabilities for millimeter-level distance changes, posing serious safety hazards.

[0005] Furthermore, position verification mainly relies on intermittent radiation-exposed imaging techniques (such as cone-beam CT), which cannot provide radiation-free continuous monitoring throughout the treatment process. This results in the inability to detect and dynamically compensate for minute displacements of the patient in a timely manner, significantly increasing treatment uncertainty.

[0006] To address the aforementioned issues, existing technologies urgently need improvement. Summary of the Invention

[0007] The purpose of this application is to provide a positioning system and method for radiotherapy beam alignment and fixation, which has the advantages of achieving six-dimensional precise positioning, reducing target area position deviation, automating the positioning process to shorten time, enhancing safety protection, and providing radiation-free continuous monitoring throughout the treatment process.

[0008] This application provides a radiotherapy beam alignment and fixation positioning system, comprising: a support device, a positioning motion device, a positioning guide device, and a control device; the support device is used to support the patient; the positioning motion device is connected to the support device and is used to adjust the position and tilt of the support device; the positioning guide device includes a reference positioning unit, a positioning registration unit, and a real-time verification unit; the reference positioning unit is used to provide a spatial reference; the positioning registration unit is used to acquire image data to obtain the difference between the actual position and the planned position of the patient's target area; the real-time verification unit is used to continuously monitor the patient's body surface displacement during treatment; the control system controls the positioning motion device to adjust the position and tilt of the support device based on the treatment plan and data from the positioning guide device.

[0009] Furthermore, the positioning system also includes a support device; the support device moves with the load-bearing device and is used to support the load-bearing device when preset conditions are met.

[0010] Furthermore, multiple sets of six-dimensional force sensors or six-dimensional torque sensors are connected in series between the end flange of the positioning motion device and the interface of the bearing device; the six-dimensional force sensors or six-dimensional torque sensors are strain gauge sensors with internal strain gauges arranged in an array; the six-dimensional force sensors or six-dimensional torque sensors are used to trigger the protection mode of the positioning system when the contact force or torque reaches a preset threshold.

[0011] Furthermore, the support device is configured as a carbon fiber composite treatment bed; multiple sets of thin-film pressure sensors are respectively installed on the upper surface and four corners of the treatment bed board to acquire local pressure data of the bed board; multiple sets of fiber optic grating sensors are built into the carbon fiber layup of the bed board to acquire deformation data of the bed board.

[0012] Furthermore, at least 8 sets of fiber Bragg grating sensors are arranged longitudinally along the bed board, with the spacing between each set of fiber Bragg grating sensors not exceeding 300mm.

[0013] Furthermore, the positioning motion device is configured as a robotic arm, and depth cameras are installed at the four corners of the bed board and the wrist of the robotic arm; the depth cameras are used to obtain the spatial relationship between the robotic arm and the bed board and other devices, so as to avoid collisions between the robotic arm and the bed board and other devices.

[0014] Furthermore, a laser scanner is installed at the edge of the motion area of ​​the treatment bed. The laser scanner is used to acquire the outline of objects within a preset range of the treatment bed. When the outline of an object approaching the warning range of the treatment bed is identified as a human body, an alarm mode is triggered.

[0015] This application also provides a placement method, the method comprising: Step 1: Based on the theoretical treatment position of the patient obtained through the treatment plan, the control system controls the reference positioning unit to project a positioning grid onto the surface of the treatment bed to assist in patient positioning. Step 2: Based on the target treatment pose of the robotic arm obtained through the treatment plan, the control system pre-simulates the motion path of the robotic arm in a virtual 3D environment to detect the collision risk between the robotic arm and the treatment bed and obstacles. Step 3: If there is no risk of collision on the pre-planned path of the robotic arm, the control system controls the robotic arm to move according to the pre-planned path; Step 4: Control the positioning and registration unit to collect positioning reference data of the patient's target area and perform image registration with the digital reconstructed image of the treatment plan to obtain the positional deviation between the actual position and the planned position of the patient's target area. Step 5: Based on the difference between the actual position and the planned position, the robotic arm adjusts the posture of the treatment bed until the difference between the actual position and the planned position is no greater than a preset allowable threshold. Step 6: Collect and reconstruct the three-dimensional point cloud of the patient's body surface through the real-time verification unit, and define the three-dimensional point position of the body surface as the body surface reference benchmark for real-time monitoring of the patient's body surface displacement.

[0016] Furthermore, following step 6, the following steps are also included: Real-time monitoring of the patient's displacement relative to a body surface reference baseline; When the real-time displacement on the body surface is greater than 2 mm and the duration is longer than the preset duration, the boron neutron capture therapy device is controlled by the control system to stop the neutron beam output. Within a preset time window, the patient's body surface displacement is checked to see if it returns to a baseline range of less than or equal to 2 mm; If the patient's body surface displacement cannot return to the reference range, the control system re-executes steps 4 to 6.

[0017] Furthermore, after step 6, the method further includes: The control system synchronously acquires the actual pose of the robotic arm from the encoder, the image registration results from the positioning and registration unit, and the three-dimensional point cloud data of the body surface collected by the real-time verification unit. Redundancy position verification is performed on the three. If the translational deviation between any two is greater than 1 mm or the attitude rotation deviation is greater than 0.5°, the redundancy position verification is deemed to have failed. If the redundancy check fails, the control system stops the treatment process and prompts for re-verification.

[0018] As can be seen from the above, the radiotherapy beam alignment and fixation system and method provided in this application achieves automated and precise positioning and continuous monitoring by integrating a control device, a support device, a positioning motion device, and a positioning guide device. It has the advantages of achieving six-dimensional precise positioning, reducing target area position deviation, automating the positioning process to shorten time, enhancing safety protection, and providing radiation-free continuous monitoring throughout the treatment process. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of one installation method of the robotic arm provided in an embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of another installation method for the robotic arm provided in an embodiment of the present invention.

[0021] Figure 3 This is a flowchart illustrating the placement method provided in an embodiment of the present invention.

[0022] Figure 4 This is a schematic diagram of the placement system provided in an embodiment of the present invention. Detailed Implementation

[0023] The technical solutions in specific embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The components described and shown in the accompanying drawings of the present invention can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the 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 present invention without inventive effort are within the scope of protection of the present invention.

[0024] The common English terms or letters used in this invention for clarity of description, as well as the concepts used, are for illustrative purposes only and not for limiting interpretation or specific usage. They should not be construed as limiting the scope of protection of this invention based on their Chinese translations or specific letters. Furthermore, in the description of this application, terms such as "first" and "second" are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0025] For ease of understanding, the following explains some key terms in this embodiment: A control device typically refers to a set of hardware and software used to receive instructions, process data, and issue control signals to coordinate the operation of various components of a system. Its function is to achieve automated operation, data management, and safety logic control of the entire placement system.

[0026] A support device is a structure that comes into direct contact with and supports the patient's body. Its main function is to provide the patient with a stable and comfortable support platform so that precise positional adjustments can be made during positioning.

[0027] A positioning and motion device refers to a mechanical structure capable of driving a support device to perform translational and rotational movements in three-dimensional space. Its function is to precisely move the support device and the patient on it to a predetermined treatment position and posture according to the requirements of the treatment plan.

[0028] A patient positioning guidance device is an integrated sensing and processing unit used to assist in patient positioning, verify positioning accuracy, and perform real-time monitoring during treatment. It acquires patient position information through various sensing technologies and compares it with planned data.

[0029] A reference positioning unit is a device used to establish a repeatable and traceable spatial reference coordinate system within the treatment space. Its function is to provide a unified reference standard for the patient's initial positioning and subsequent position verification.

[0030] A positioning and registration unit is a device used to acquire the actual location information of the patient's target area and compare it with the pre-set target area location in the treatment plan. It quantifies the deviation between the actual and planned locations through image acquisition and processing technology.

[0031] A real-time verification unit is a device used to continuously monitor changes in the patient's body position during treatment. Its function is to ensure the patient remains in a preset position during treatment and to provide early warnings or trigger interventions when displacement occurs.

[0032] This application proposes a radiotherapy beam alignment and fixation positioning system, including a support device, a positioning motion device, a positioning guide device, and a control device. The support device supports the patient; the positioning motion device is connected to the support device and is used to adjust the position and tilt of the support device; the positioning guide device includes a reference positioning unit, a positioning registration unit, and a real-time verification unit; the reference positioning unit provides a spatial reference; the positioning registration unit acquires image data to obtain the difference between the actual and planned positions of the patient's target area; the real-time verification unit continuously monitors the patient's surface displacement during treatment. By integrating the above devices, this system effectively solves the aforementioned technical problems, comprehensively improving positioning accuracy, operational efficiency, safety protection capabilities, and real-time monitoring capabilities; the control system, based on the treatment plan and data from the positioning guide device, controls the positioning motion device to adjust the position and tilt of the support device.

[0033] The control device is a core management component of a radiotherapy beam alignment and fixation positioning system. The control device can adopt a centralized control architecture, specifically a central processing unit, such as an industrial control computer, which internally runs control application software adapted to the system's specific logic. Alternatively, the control device can adopt a distributed control architecture, composed of multiple microcontrollers or programmable logic controllers (PLCs). Each controller corresponds to a different sub-functional module of the positioning system, and the components communicate with each other via an industrial communication network to achieve real-time data interaction, command transmission, and coordinated control.

[0034] In this preferred embodiment, the control device is configured as a central control system, which is equipped with a real-time operating system and adopts a standardized modular architecture design. The central control system integrates and divides functionally independent but mutually cooperative logical units, specifically including: a motion control module for driving and regulating the actions of the lower-level machine, a perception fusion module for multi-source detection data fusion and analysis, a safety decision module for determining abnormal body position and safety interlock protection, and a treatment process module for coordinating the entire process of time sequence logic, so as to ensure the orderly and stable operation of the entire system.

[0035] The support device is designed to support a patient. For example, the support device can be a flat plate made of high-strength material on which the patient can lie flat or on their side. Alternatively, the support device can also be an adjustable support structure, for example, composed of multiple independently adjustable modules, to accommodate the comfort and support needs of patients of different body types.

[0036] The positioning motion device is connected to the support device and is used to adjust the position and tilt angle of the support device. Specifically, the positioning motion device can consist of multiple linear actuators and rotary joints. By precisely controlling the extension, contraction, and rotation of these actuators, the support device can achieve six degrees of freedom of movement in three-dimensional space.

[0037] The placement guidance device includes a reference positioning unit, a placement registration unit, and a real-time verification unit. This combination is designed to provide comprehensive placement assistance and monitoring functions.

[0038] A reference positioning unit is used to provide a spatial reference. For example, a reference positioning unit can be a laser projector that projects preset reference lines or dot patterns into the treatment space to help the operator align the patient's initial position with the treatment plan.

[0039] The positioning and registration unit is used to acquire image data to determine the difference between the actual and planned positions of the patient's target area. For example, the positioning and registration unit can be an orthogonal digital radiography (DR) system that acquires two-dimensional projected images of the patient's internal anatomy after positioning and extracts or registers key anatomical landmarks using image processing algorithms. The actual spatial coordinates of these landmarks are then compared with the corresponding digitally reconstructed radiographs in the treatment plan to calculate the deviation between the actual and planned positions of the patient's target area.

[0040] The real-time verification unit is used to continuously monitor the patient's body surface displacement during treatment. Specifically, the real-time verification unit can employ a surface-guided radiation therapy (SGRT) system. This system is equipped with a multi-view infrared camera array, with each sensor deployed around the treatment space. It continuously emits and receives infrared detection signals, and reconstructs and fits the three-dimensional contour data of the patient's body surface in real time. By performing differential comparison and computational analysis on the continuously acquired body surface contour data, it accurately identifies and monitors the positional shifts that occur during the patient's radiotherapy treatment. In another preferred embodiment, the real-time verification unit employs a visual tracking monitoring system, which uses one or more high-definition cameras to continuously acquire image information of the patient's body surface feature points and positioning markers, and calculates the three-dimensional spatial coordinates of the feature points and markers in real time. This allows for high-precision monitoring of minute displacement changes in the patient's body, ensuring the stability of the radiotherapy position.

[0041] This embodiment presents a radiotherapy beam alignment and fixation system that integrates control, load-bearing, motion, and guidance devices to achieve high-precision six-degree-of-freedom positioning of the patient's target area, effectively addressing the shortcomings of traditional positioning systems in complex positioning scenarios. Simultaneously, the introduction of a multimodal guidance device significantly improves the automation and operational efficiency of the positioning process and establishes a radiation-free, real-time monitoring capability throughout the entire process from initial positioning to treatment completion, thereby comprehensively ensuring the accuracy and safety of boron neutron capture therapy.

[0042] When the support device is moved to a distal position, the lack of support may lead to insufficient stability and deformation risk, affecting positioning accuracy and treatment safety. To address this, the positioning system further includes a support device; the support device is located on the ground at the distal end of the support device and moves with the support device to support the support device when preset conditions are met.

[0043] In this design, the end of the positioning motion device connected to the load-bearing device is the proximal end, and the end relatively farther from the positioning motion device is the distal end. Specifically, the support device is a mechanism designed to provide additional physical support, enhancing the structural stability and rigidity of the load-bearing device under specific operating conditions. This support device can be a pneumatically adaptive support column, whose extension and support force are controlled by a pneumatic system to achieve flexible contact and adaptive support.

[0044] The support device is positioned on the ground at the distal end of the load-bearing device to ensure that the support point is located in the area where the load-bearing device is most prone to deformation or instability during movement, thereby providing effective physical support directly to that area. This arrangement can manifest as the support device being mounted on the ground and contacting the distal end of the load-bearing device via its own telescopic or rotating mechanism; alternatively, the support device can be mounted on a movable base that moves on the ground via guide rails or wheels to follow the distal end of the load-bearing device.

[0045] The supporting device moves in tandem with the carrying device to ensure that the supporting device dynamically follows the movement trajectory of the carrying device, thereby maintaining effective support throughout the movement of the carrying device and preventing support failure due to positional changes. The following methods can include: the supporting device integrating an independent motion control system that uses sensors, such as laser rangefinders and encoders, to acquire real-time information on the remote position and attitude of the carrying device and adjust its own posture accordingly to maintain contact or proximity; or, the supporting device can be linked with a positioning motion device to achieve synchronized movement by sharing motion commands or feedback signals, ensuring that the supporting device is always located below or to the side of the remote end of the carrying device.

[0046] The support device is used to support the bearing device when preset conditions are met. The preset conditions may be that the tilt angle of the bearing device exceeds a preset threshold, such as 5°, or that the deflection or displacement of the far end of the bearing device exceeds a preset threshold, such as 2mm. In this case, the support device automatically extends and establishes flexible contact with the far end of the bearing device. The support force is controlled within the range of 50N to 200N by a force sensor to provide auxiliary support. When the positioning motion device drives the bearing device to move, the support device automatically retracts and maintains a 20mm gap to avoid unnecessary interference.

[0047] By introducing a support device into the aforementioned positioning system, and placing it on the ground at the distal end of the supporting device, allowing it to move with the supporting device, the system can actively provide support based on preset conditions when the supporting device moves to the distal position or is in a specific posture. This effectively solves the problem of insufficient stability and deformation risk of the supporting device at the distal position due to lack of support. Furthermore, since the support device is triggered on demand, it avoids interference with the movement of the supporting device when support is not needed, thus optimizing the system's operational efficiency and flexibility.

[0048] Furthermore, multiple sets of six-dimensional force sensors or six-dimensional torque sensors are connected in series between the end flange of the positioning motion device and the interface of the bearing device; the six-dimensional force sensors or six-dimensional torque sensors are strain gauge sensors with internal strain gauges arranged in an array; the six-dimensional force sensors or six-dimensional torque sensors are used to trigger the protection mode of the positioning system when the contact force or torque reaches a preset threshold.

[0049] The end flange of the positioning motion device is the standard mechanical interface connecting its actuator to the external load, while the interface of the load-bearing device is the corresponding structure connecting it to the positioning motion device. Specifically, the end flange of the robotic arm is rigidly connected to the near end of the load-bearing device through a quick-change high-rigidity docking interface; the quick-change high-rigidity docking interface adopts a composite positioning and locking structure with conical centering and pin bidirectional locking. The overall structural rigidity of this interface is ≥107 N / m, which can suppress docking deformation and relative displacement.

[0050] By connecting multiple sets of sensors in series between the two components, these sensors are positioned along the force or torque transmission path, enabling direct measurement of the force or torque acting on the load-bearing device. Multiple sets improve measurement redundancy and reliability; for example, three or four sets of sensors can be evenly distributed circumferentially along the connection interface to more comprehensively capture the torque distribution. A six-dimensional force sensor or six-dimensional torque sensor can simultaneously measure forces and torques in three orthogonal directions, providing a comprehensive description of the force state of the object.

[0051] A six-dimensional force sensor or six-dimensional torque sensor is a strain gauge sensor. Its working principle is based on the characteristic of the change in resistance when a material deforms under stress. It has advantages such as high precision, high sensitivity, fast response speed, and compact structure, making it suitable for dynamic force / torque measurement. The sensor internally incorporates an array of strain gauges, meaning multiple sets of strain elements are regularly arranged in a preset specific geometric configuration. This enables precise decoupled acquisition of multi-dimensional spatial force and torque signals, effectively improving the measurement system's resistance to environmental interference and overall measurement accuracy.

[0052] Specifically, the axial force measurement range Torque measurement range The signal sampling frequency is not lower than Multiple strain gauges can be connected using a Wheatstone bridge circuit to compensate for temperature changes and improve the stability of the signal output; alternatively, a distributed fiber Bragg grating sensor array can be used to obtain force / torque information by measuring the spectral drift caused by fiber strain.

[0053] A six-dimensional force sensor or a six-dimensional torque sensor is used to trigger the protection mode of the placement system when the contact force or torque reaches a preset threshold. The preset threshold refers to the maximum permissible contact force or torque value determined during the system design and safety assessment phases. Once the actual measured value exceeds this threshold, a potential hazard is considered to exist.

[0054] Triggering the protection mode of the positioning system refers to the control system immediately taking a series of preset safety measures when the sensor detects an anomaly such as force or torque exceeding a preset threshold. In a specific embodiment, the protection mode has two levels of mechanisms. The first level is a warning, triggered when the contact force > 20N or the torque > 5Nm. At this time, the control system controls the positioning motion device, such as a robotic arm, to reduce its speed by 10%. The second level is an emergency stop, triggered when the contact force > 50N or the torque > 10Nm. At this time, the control system immediately controls the positioning motion device to stop moving and locks the robotic arm's movement. By triggering different mechanisms based on different conditions, false alarms can be avoided while also effectively preventing damage caused by collisions.

[0055] Preferably, the robotic arm is also equipped with a proximity sensor, which is a non-contact position detection sensor that can sense the presence and relative spatial distance of surrounding objects and obstacles in real time without physical contact. It converts the physical distance signal into an electrical signal that can be recognized by the control system, thereby realizing near-distance collision avoidance prediction and real-time monitoring of spatial gaps, and providing a front-end detection data source for equipment speed limiting, safety interlocking and emergency stop protection.

[0056] Taking the real-time verification unit SGRT as an example, the positioning system integrates and collects six-dimensional force sensor data, proximity sensor detection data, and SGRT multi-source sensing information in real time during operation. Relying on the integrated sensing data and combined with the adaptive PID (Proportional-Integral-Derivative) closed-loop control algorithm, the system dynamically adjusts the movement speed of the robotic arm in real time to achieve graded safety speed limits and emergency protection control: when the real-time distance between the robotic arm and surrounding obstacles is less than 100mm, the control system limits the real-time movement speed of the robotic arm to 30% of the rated maximum operating speed setting; when the real-time distance between the robotic arm and surrounding obstacles is less than 30mm, or when the mechanical signal detected by the six-dimensional force sensor in real time reaches the preset emergency stop trigger threshold, the control device immediately issues an emergency stop control command to the robotic arm to lock the movement of the robotic arm, avoid the risk of collision and squeezing, and ensure the safety of the equipment and the patient.

[0057] Through the above technical solution, the contact force or torque between the positioning motion device and the support device can be monitored in real time and accurately during the adjustment of the position and tilt angle of the support device. When an abnormality is detected, the system can quickly trigger the protection mode, thereby effectively avoiding equipment damage and patient injury caused by overload, collision, or abnormal contact. At the same time, the strain gauge sensor and its internal array of strain gauges ensure the sensitivity, accuracy, and reliability of force / torque measurement, providing accurate real-time feedback to the system and further improving the overall stability and reliability of the system.

[0058] Furthermore, the support device is configured as a carbon fiber composite treatment bed; multiple sets of thin-film pressure sensors are respectively installed on the upper surface and four corners of the treatment bed board to acquire local pressure data of the bed board; multiple sets of fiber optic grating sensors are built into the carbon fiber layup of the bed board to acquire deformation data of the bed board.

[0059] Specifically, a carbon fiber composite treatment bed is a structure made of carbon fiber reinforced resin matrix, characterized by its lightweight, high strength, high stiffness, and good X-ray permeability. This material configuration allows the treatment bed to maintain extremely high structural stability when supporting a patient, effectively resisting external loads and deformations generated during movement.

[0060] In practice, the treatment bed is made of T800 grade carbon fiber composite material. Combined with finite element simulation analysis and patient load distribution simulation results, the bed structure is topologically optimized to achieve the optimal balance between lightweight design and load-bearing stability. Specific performance parameters meet the following requirements: bed weight ≤ 20kg, total length 2.0m, and maximum elastic deformation ≤ 1.5mm under a rated load of 180kg across the entire span, ensuring no significant deformation affects positioning accuracy during load-bearing. The bed board integrates a honeycomb sandwich reinforcement structure, which further enhances the local and overall structural stiffness of the bed board, preventing deformation caused by uneven local stress. Simultaneously, coupled dynamic modeling analysis of the bed and the mounted robotic arm is performed. Through structural optimization, the bed's modal natural frequency is made > 30Hz, effectively suppressing resonant vibrations generated during movement and ensuring radiotherapy positioning accuracy and equipment stability. The use of carbon fiber composite material significantly improves the overall rigidity and stability of the load-bearing device, providing the patient with a robust and minimally deformable support platform, thereby ensuring positioning accuracy.

[0061] Thin-film pressure sensors are flexible, ultra-thin pressure sensing elements. Their core function is to convert pressure signals acting on their surface into precisely measurable electrical signals, adapting to the flexible installation and high-precision monitoring requirements of treatment beds. Thin-film pressure sensors operate on the piezoresistive principle, detecting changes in the resistance of the thin-film sensing material under pressure in real time. After signal conversion, the corresponding pressure data is obtained, offering advantages such as high sensitivity and accurate measurement. Multiple sets of these sensors are placed on the surface and edges of the treatment bed board to achieve real-time, precise monitoring of the pressure distribution in the area where the patient contacts the bed board. This helps identify changes in patient position, points of excessive local pressure, or abnormal contact conditions, providing crucial data for patient comfort and safety.

[0062] Specifically, the surface film pressure sensor is arranged in an array. The sensor array is made of flexible piezoresistive film and its density is 4×6 dots / m². It is used to monitor local pressure abnormalities in various areas of the bed board in real time. The pressure abnormalities include scenarios such as patient body displacement and external objects colliding with the bed board. The pressure abnormality trigger threshold of the sensor array is set to >15kPa. When the monitored local pressure exceeds this threshold, an abnormal signal can be issued in time.

[0063] Fiber Bragg grating (FBG) sensors are optical sensors based on FBG technology. They work by measuring physical quantities such as strain and temperature by monitoring the drift of the center wavelength of the grating's reflection spectrum. These sensors are embedded in the carbon fiber layup of the bed board, ensuring good coupling between the sensor and the bed board material, thus capturing the minute deformation data generated by the bed board under stress or during movement more directly and accurately. They can be directly embedded during layup or implanted into predetermined positions within the carbon fiber composite material after the bed board is formed using precise minimally invasive techniques. These sensors provide continuous, high-precision deformation feedback, which is crucial for maintaining geometric accuracy during the positioning process.

[0064] Furthermore, at least 8 sets of fiber Bragg grating sensors are arranged longitudinally along the bed board, with the spacing between each set of fiber Bragg grating sensors not exceeding 300mm.

[0065] Specifically, each sensor group can consist of multiple gratings connected in series on a single optical fiber, or multiple independent fiber Bragg grating sensors. The eight fiber Bragg grating sensors can utilize eight independent optical fibers, each integrating one or more gratings, arranged at different locations on the bed board; alternatively, a single long optical fiber can be used, on which eight or more gratings are etched to form a distributed sensing array, which is then deployed with eight main monitoring points.

[0066] The longitudinal direction of the bed board refers to the length of the treatment bed board. Patients typically lie along the length of the bed board, and when the bed board bears the patient's weight, its main deformation pattern is usually bending or sagging along the longitudinal direction. Therefore, placing sensors along the longitudinal direction can directly and effectively capture this main deformation, which has the greatest impact on positioning accuracy.

[0067] The spacing between each group of fiber Bragg grating sensors should not exceed 300mm, meaning the center-to-center distance between two adjacent groups of fiber Bragg grating sensors should not exceed 300mm in the longitudinal direction. This uniform spacing design aims to achieve continuous, blind-spot-free acquisition of bed deformation data. For example, if the total length of the bed is 2400mm, the eight groups of sensors spaced at 300mm intervals can cover the entire effective length of the bed, ensuring that deformation occurring at any location on the bed can be effectively detected. This uniform distribution strategy avoids missing local deformations due to sparse or irregular sensor placement, ensuring the continuity and consistency of deformation data acquisition, thereby providing high-precision and high-reliability data support for subsequent positioning adjustments.

[0068] Furthermore, the positioning motion device is configured as a robotic arm, and depth cameras are installed at the four corners of the bed board and the wrist of the robotic arm; the depth cameras are used to obtain the spatial relationship between the robotic arm and the bed board and other devices, so as to avoid collisions between the robotic arm and the bed board and other devices.

[0069] The positioning and motion device is configured as a robotic arm. A robotic arm is a programmable automated device with multiple joints and degrees of freedom, capable of achieving spatial motion with complex trajectories and postures. It can be implemented using serial robotic arms commonly found in industrial applications, such as six-axis robots, which are characterized by a large range of motion and high flexibility, capable of covering the vast space required for boron neutron capture therapy. As the driving core of the support device, the robotic arm provides high-precision six-degree-of-freedom spatial positioning and posture adjustment capabilities to meet the precise positioning requirements of the patient's target area in complex positions during boron neutron capture therapy.

[0070] Specifically, a high-precision heavy-duty industrial robotic arm is selected, with rated technical parameters meeting the following requirements: repeatability accuracy ≤ 0.1mm, rated effective load ≥ 300kg. The fixed base of the robotic arm is fixed to the main load-bearing beam of the treatment room ceiling through rigid connectors, the fixed base is matched and installed on the pre-embedded installation base in the ground, or the fixed base of the robotic arm is mounted on a preset high-precision sliding guide rail mechanism. The guide rail mechanism is fixed to the floor or wall of the treatment room through rigid connectors to ensure the vibration resistance and installation rigidity of the whole machine installation structure, while adapting to the treatment position requirements of different patients and the requirements of equipment linkage operation.

[0071] like Figure 1 As shown, the 6-axis robotic arm is fixed to a pre-embedded mounting base on the floor of the treatment room. Figure 2As shown, the 6-axis robotic arm is mounted on a slide rail mechanism.

[0072] The robotic arm is connected to the control device of the treatment equipment and can receive six-dimensional target pose control commands issued by the control device. The robotic arm has a built-in trajectory smooth interpolation control module and a dynamic feedforward compensation control module, which can dynamically adjust the motion process in real time to ensure that the whole machine moves smoothly, without impact or shaking, and improve the safety and alignment accuracy of the patient positioning process.

[0073] Meanwhile, depth cameras are installed at the four corners of the bed board and on the wrist of the robotic arm. A depth camera is a sensor that can acquire real-time 3D depth information of objects in a scene, working by measuring light propagation time, structured light pattern deformation, or binocular parallax. Specifically, a depth camera based on the time-of-flight (ToF) principle can be selected, which has the advantages of fast measurement speed, strong resistance to ambient light interference, and suitability for dynamic scenes; or a depth camera based on the structured light principle can be selected, which has the advantages of high measurement accuracy and the ability to acquire detailed 3D point cloud data.

[0074] Depth data or 3D point clouds collected by depth cameras can reconstruct the 3D geometric information of the robotic arm, bed board, and surrounding environment (such as treatment head, imaging equipment, collimator, walls, etc.) in real time, thereby calculating the relative distance, relative position, and potential contact area between them. This helps the control system predict possible collision events between the robotic arm and bed board during movement and take different countermeasures.

[0075] One approach is to use point cloud processing algorithms, such as the iterative nearest point algorithm or its variants, to register real-time point cloud data with a pre-established 3D model of the device, thereby accurately determining the relative pose. Another approach is to directly set the region of interest or a safe distance threshold in the depth image. When an object is detected entering these regions, it is determined that there is a potential change in spatial relationship.

[0076] The effective measurement range of the ToF depth camera is set to 0.1m to 5m, with a ranging accuracy of ±2mm. The ToF depth camera can perform real-time scanning and acquisition of the monitoring area and dynamically construct a voxel map of the scene. The map updates at a real-time frame rate of no less than 10Hz. This multi-point, full-domain dynamic depth perception capability can perform uninterrupted real-time environmental monitoring and distance identification in easily interfered areas within the treatment space. Simultaneously, the control device has preset graded safety protection thresholds: a preset safety warning threshold of 100mm and a preset emergency stop protection threshold of 30mm. When the relative distance between the robotic arm, treatment bed, and surrounding auxiliary equipment and wall structures detected in real time is less than the safety warning threshold, the whole machine control system triggers a safety warning prompt in real time. When the relative distance further decreases to or below the emergency stop protection threshold, the control system immediately issues an emergency stop control command, locking the motion output of the robotic arm and treatment bed.

[0077] Furthermore, a laser scanner is installed at the edge of the motion area of ​​the treatment bed. The laser scanner is used to acquire the outline of objects within a preset range of the treatment bed. When the outline of an object approaching the warning range of the treatment bed is identified as a human body, an alarm mode is triggered.

[0078] A laser scanner is a sensor that uses a laser beam for non-contact distance measurement and environmental sensing. It is mounted at the edge of the movement area of ​​a treatment bed to monitor the environment in real time to identify potential obstacles or people.

[0079] Laser scanners precisely calculate the distance to objects by emitting laser pulses and measuring the time or phase changes of their reflection from the object's surface. Through continuous scanning, this distance data can be integrated to depict the object's geometry and boundaries, i.e., its outline. For example, a 2D laser scanner acquires the two-dimensional cross-sectional outline of the object on a specific scanning plane. By analyzing changes in these two-dimensional outlines, the system can determine the object's presence, size, and direction of movement. For 3D lidar, it directly generates three-dimensional point cloud data of the object's surface. By processing this point cloud data, such as using clustering or surface reconstruction algorithms, the complete three-dimensional outline information of the object can be extracted. Simultaneously, machine learning or deep learning algorithms can be used to train and analyze the point cloud data or outline images acquired by the laser scanner to achieve intelligent human recognition; alternatively, it can be combined with other auxiliary information for judgment. If a thermal imaging sensor is integrated into the system, heat source characteristics can be used to assist in verifying whether it is a human body. The preset range is a configurable parameter, the size of which is usually determined based on the actual space of the treatment room, the maximum range of motion of the treatment bed, and the required protection level.

[0080] Specifically, a 2D laser scanner is fixedly installed at the boundary of the entire motion area of ​​the treatment bed. The configuration parameters of this 2D laser scanner meet the following requirements: effective scanning angle. Maximum effective detection radius Multiple independent protective light curtains are arranged vertically in layers, with each curtain set at a height above the ground. The system performs contour feature calculation and target classification and recognition on the scanned data in real time. When a target intruding into the protective light curtain is determined to be a human body, the entire control system triggers an alarm mode. The alarm mode responds in stages according to the level of danger. When an object enters a relatively distant area... When the object moves closer to the target area, the system can first emit a soft prompt and slow down the movement of the treatment bed; as the object moves further into the target area... When the area is identified as containing a human body, a strong audible and visual alarm is triggered; when the object eventually enters a closer area... When the area is identified as a human body, an emergency stop is immediately triggered and a loud audible and visual alarm is emitted.

[0081] Through the above technical solution, the positioning system of this application can realize real-time, non-contact monitoring of the environment around the movement area of ​​the treatment bed, effectively obtain object contour information, and avoid the collision risk that may occur when the robotic arm and the treatment bed move in complex movement paths and narrow treatment spaces.

[0082] In existing techniques, the patient placement process relies on manual operation, which is inefficient, lacks collision risk prediction, and lacks real-time position monitoring during treatment. To address this, this application proposes a placement method comprising the following steps: Step 1: Based on the theoretical treatment position of the patient obtained through the treatment plan, the control system controls the reference positioning unit to project a positioning grid onto the surface of the treatment bed to assist in patient positioning. Step 2: Based on the target treatment pose of the robotic arm obtained through the treatment plan, the control system pre-simulates the motion path of the robotic arm in a virtual 3D environment to detect the collision risk between the robotic arm and the treatment bed and obstacles. Step 3: If there is no risk of collision on the pre-planned path of the robotic arm, the control system controls the robotic arm to move according to the pre-planned path; Step 4: Control the positioning and registration unit to collect positioning reference data of the patient's target area and perform image registration with the digital reconstructed image of the treatment plan to obtain the positional deviation between the actual position and the planned position of the patient's target area. Step 5: Based on the difference between the actual position and the planned position, the robotic arm adjusts the posture of the treatment bed until the difference between the actual position and the planned position is no greater than a preset allowable threshold. Step 6: Collect and reconstruct the three-dimensional point cloud of the patient's body surface through the real-time verification unit, and define the three-dimensional point position of the body surface as the body surface reference benchmark for real-time monitoring of the patient's body surface displacement.

[0083] Specifically, such as Figure 3 As shown.

[0084] In step 1, the theoretical treatment position for the patient refers to the ideal spatial position and orientation of the patient's target area within the coordinate system of the treatment system, predetermined in the treatment plan. This position is typically determined jointly by physicians and physicists through a combination of medical imaging and the treatment planning system.

[0085] The reference positioning unit can include, but is not limited to, laser projectors, structured light projectors, or LED array projectors. These devices can accurately project a preset positioning grid onto the surface of the treatment bed or the patient's body, providing intuitive visual assistance for the patient's initial positioning. The positioning grid is a series of regularly arranged lines or dots used to guide the patient or operator to roughly place the patient in the correct initial position, reducing the time and error of initial positioning.

[0086] Specifically, the reference positioning unit uses a cross laser projector and an adjustable mark laser, with the following configuration parameters: wavelength Line width This involves using 635nm linewidth red light to generate a reference cross and an adjustable, regularized positioning grid on the patient's body surface, enabling rapid visualization and definition of the patient's initial position.

[0087] In step 2, the target treatment pose of the robotic arm refers to the final spatial position and posture that the robotic arm should achieve when completing the treatment task, as determined in the treatment plan. The virtual 3D environment is a digital simulation space that includes precise 3D models of the robotic arm, treatment bed, patient model, treatment equipment such as neutron beam apertures, and other potential obstacles. This environment can be constructed using specialized robotic simulation software or customized CAD / CAM software.

[0088] The pre-simulation of the robotic arm's motion path refers to the control system simulating the robotic arm's motion trajectory from its current position to the target pose in a virtual 3D environment before the actual movement. If the distance between the robotic arm, the treatment bed and the patient model it carries, and other objects in the environment (such as beam apertures, imaging equipment, walls, etc.) is less than the preset safe distance, a collision risk is determined.

[0089] In one specific embodiment, based on the robot's inverse kinematics model and real-time collision detection algorithm, the control device can simulate and pre-run the robot arm's preset motion path within a digital virtual 3D simulation environment. It can also detect the relative spatial positions and interference gaps between the robot arm and static and dynamic obstacles in the scene during its movement in real time, predicting spatial collision risks. The response time required for a single complete intelligent planning and risk assessment is less than 1 second, ensuring the real-time performance and clinical adaptability of the motion planning.

[0090] In step 3, when there is no risk of collision, that is, when the virtual simulation shows that the robotic arm maintains a safe distance from all obstacles along the entire motion path, the control system controls the robotic arm to move along the pre-simulated path. This is usually achieved by sending motion commands to the controllers of each joint of the robotic arm. These commands can be joint angle sequences, end effector pose sequences, or speed commands to ensure that the robotic arm moves accurately and smoothly along the pre-simulated collision-free path.

[0091] In step 4, the positioning and registration unit is used to acquire positioning reference data for the patient target area. This data may include, but is not limited to, orthogonal digital X-ray imaging systems or ultrasound imaging systems, to obtain the actual spatial location information of the patient target area at the current moment. The patient target area refers to the tumor region that needs to be treated, and the positioning reference data is the raw data used for subsequent registration, such as X-ray images or ultrasound images.

[0092] Digital reconstructed images for treatment planning are typically digital images with target areas and organ-at-risk contours generated from the patient's computed tomography (CT) or magnetic resonance imaging (MRI) data, serving as a reference standard for registration.

[0093] Image registration is the process of spatially aligning acquired positioning reference data with digitally reconstructed images of the treatment plan. Its purpose is to determine the precise spatial transformation between the actual and planned positions of the patient's target area, thereby calculating the positional deviation between the two. Image registration algorithms can employ feature-point-based, gray-scale-based, or model-based registration methods.

[0094] Specifically, the positioning and registration unit employs a dual-panel detector and a microfocus X-ray source with a pixel size of 0.2mm and an imaging time of <200ms, enabling rapid, high-resolution real-time imaging. It also incorporates a built-in 2D / 3D automatic registration algorithm, matching bony structures based on the patient's preoperative CT images and real-time acquired digital X-ray images. By extracting key bony landmarks and comparing their spatial coordinates, it calculates the deviation between the actual target area position and the planned treatment position, achieving a registration accuracy of ≤0.5mm.

[0095] In step 5, pose adjustment refers to the control system generating corresponding robotic arm motion commands based on the difference between the actual position and the planned position calculated in step 4. This drives the robotic arm to translate and rotate the treatment bed, reducing or eliminating the difference. A preset allowable threshold is the maximum deviation between the actual and planned positions allowed by the system, typically in the millimeter or sub-millimeter range, such as 0.5mm, to ensure treatment accuracy. When the difference is less than or equal to this threshold, the patient is considered to have achieved precise positioning; when the difference is greater than this threshold, the system automatically calculates the deviation between the actual position of the patient's target area and the planned treatment position and adjusts the robotic arm pose until the difference is less than or equal to the threshold or the system completes a preset number of operations, at which point it stops and reports an error to prevent the system from freezing.

[0096] In step 6, the real-time verification unit is used to continuously monitor the patient's surface displacement during treatment. This unit may include, but is not limited to, optical surface-guided radiotherapy systems and laser scanners. These devices are capable of non-contact acquisition of geometric data from the patient's surface. The 3D point cloud of the body surface is a collection of discrete points on the patient's surface acquired by the real-time verification unit. Each point contains 3D coordinate information, collectively forming a digital model of the patient's body surface.

[0097] After the patient completes precise target area positioning and calibration, a three-dimensional point cloud of the patient's body surface is acquired in the current state and calibrated as the body surface reference state. Real-time body surface displacement monitoring involves synchronously registering and comparing the three-dimensional point cloud of the body surface acquired frame by frame during treatment with the body surface reference state, calculating the offset displacement of the patient's body surface relative to the reference, and thus determining the dynamic positional changes of the patient's treatment position in real time.

[0098] Specifically, the real-time verification unit employs a multi-view infrared camera array with a camera resolution of [missing information]. Frame rate of acquisition It is used for high-speed reconstruction of real-time 3D point clouds of patient body surface and non-rigid image registration with reference topography, with a body surface displacement monitoring accuracy of no more than [value missing]. .

[0099] Figure 4 This is a schematic diagram of a positioning system for radiotherapy beam alignment and fixation, wherein the reference positioning unit is configured as a laser positioner, the positioning registration unit is configured as an orthogonal DR system, the real-time verification unit is configured as an SGRT, the support device is configured as a carbon fiber treatment bed, and the positioning motion device is configured as a 6-axis robotic arm. Figure 4 The patient is positioned in a specific orientation on a carbon fiber bed board, and a laser locator projects a positioning grid to provide visual assistance for the patient's initial positioning.

[0100] By projecting a positioning grid using a reference positioning unit to assist in initial positioning, manual intervention is significantly reduced, with an average positioning time of less than 5 minutes, significantly improving the efficiency and accuracy of initial positioning. Secondly, before the robotic arm actually moves, motion path pre-playing and collision risk detection are performed in a virtual 3D environment, effectively avoiding the risk of collisions between the robotic arm and treatment bed and obstacles, greatly improving operational safety. Subsequently, positioning reference data of the patient's target area is collected by the positioning registration unit and image registered with the treatment plan, accurately obtaining the deviation between the actual and planned positions of the patient's target area, ensuring positioning accuracy. Based on this deviation, the robotic arm can automatically adjust the posture of the treatment bed until it reaches the preset allowable threshold, achieving high-precision automatic correction. Finally, the real-time verification unit collects and reconstructs the patient's three-dimensional point cloud as a surface reference benchmark, enabling continuous, radiation-free monitoring of the patient's surface displacement during treatment, providing crucial data for dynamic position management during treatment.

[0101] Furthermore, after step 6 above, the procedure also includes: real-time monitoring of the patient's real-time displacement relative to a reference body surface; if the real-time displacement is greater than 2 mm and the duration is longer than a preset duration, controlling the boron neutron capture therapy device to stop neutron beam emission via the control system; detecting whether the patient's displacement returns to a reference range of less than or equal to 2 mm within a preset time window; if the patient's displacement cannot return to the reference range, the control system re-executes steps 4 to 6.

[0102] The preset duration can be either 5 seconds or 3 seconds, and this embodiment does not limit it. It limits the threshold of real-time displacement and duration on the body surface to avoid accidental termination of the beam due to brief or slight physiological displacement (such as breathing or heartbeat). At the same time, it ensures that the neutron beam can be stopped in a timely and automatic manner when significant and continuous displacement occurs, thereby protecting the patient from unnecessary radiation and maintaining the accuracy of treatment.

[0103] Specifically, the control system continuously receives real-time displacement data of the body surface from the real-time verification unit. The system integrates a logic judgment module that compares the current displacement value with the displacement threshold in real time and starts a timer. Once the displacement continuously exceeds 2mm and lasts for 5 seconds, the control system immediately sends a beam stop command to the boron neutron capture therapy device, interrupting the output of the neutron beam.

[0104] A clearly defined time window and baseline range are provided to establish an automated check mechanism after treatment pauses, determining whether the patient can return to an acceptable treatment position independently or with minor adjustments. This helps reduce unnecessary repositioning operations and improves the efficiency of the treatment process. When the boron neutron capture therapy device stops neutron beam emission, the control system starts a preset timer, such as a 30-second or 1-minute time window. Within this time window, the real-time verification unit continues to monitor the patient's surface displacement, and the control system continuously checks the displacement data to determine whether it has returned to a baseline range of 2 mm or less.

[0105] If the patient's body surface displacement cannot return to the reference range, the control system re-executes steps 4 to 6, that is, automatically triggers a complete repositioning and verification process to ensure treatment accuracy and safety without manual intervention, thereby improving overall treatment efficiency and automation level.

[0106] When the patient's body surface displacement can autonomously return to the reference range, it is determined that the patient's current position is within the acceptable treatment position range, or only a slight correction is needed to meet the treatment position requirements. At this time, the control device calls the built-in position prediction and compensation model, performs calculation and analysis based on the real-time collected body surface displacement parameters, dynamically generates the corresponding dose and positioning compensation amount, and accurately corrects and compensates for the patient's body surface position deviation to ensure the accuracy of radiotherapy target area irradiation.

[0107] Furthermore, after step 6 above, the method also includes: the control system synchronously acquiring the actual pose feedback from the encoder of the robotic arm, the image registration result of the positioning and registration unit, and the three-dimensional point cloud data of the body surface collected by the real-time verification unit; performing redundant position verification on the three; if the translational deviation between any two is greater than 1mm or the posture rotation deviation is greater than 0.5°, the redundant position verification is determined to have failed; if the redundant position verification fails, the control system automatically pauses the treatment process and prompts for re-verification.

[0108] Specifically, a unified timestamp server or synchronization triggering mechanism can be used to ensure that all data acquisition modules simultaneously read and transmit data after receiving the synchronization signal. This can be achieved, for example, by connecting the sensors and control system via hardware synchronization cables, or by using the Network Time Protocol (NTP) for software-level time synchronization. Another approach is for the control system to poll or subscribe to sensor data at a very high frequency, and upon receiving all data, perform nearest neighbor matching or interpolation based on its timestamps to obtain a nearly synchronized dataset, thus providing an accurate and consistent basis for subsequent verification.

[0109] Redundancy position verification is performed on all three sensors by comparing position data from different sources to detect consistency or discrepancies, thereby identifying potential sensor malfunctions or system errors. One approach is to use geometric transformations and coordinate system conversions to unify all data into a single reference coordinate system, then calculate the translational and rotational differences between them. For example, a 3D point cloud of the body surface can be matched with a reference model of a robotic arm end effector or treatment bed using a registration algorithm, such as the Iterative Closest Point (ICP) algorithm, and compared with the image registration results. Another approach is to establish a multi-sensor fusion model, such as one based on Kalman filtering or extended Kalman filtering, using data from different sensors as input. The model predicts and updates to estimate the patient's true pose, and calculates the residual between each sensor's data and the model estimate for verification.

[0110] If the translational deviation between any two values ​​is greater than 1 mm or the attitude rotation deviation is greater than 0.5°, the redundant position verification is deemed to have failed, ensuring that the protection mechanism is only triggered by errors exceeding the clinically acceptable range. Specifically, this can be achieved by presetting these thresholds in the control system, and by directly comparing the calculated translational deviation (e.g., Euclidean distance) and attitude rotation deviation (e.g., the angular difference between quaternions or rotation matrices) with the preset thresholds.

[0111] If the redundant position verification fails, it indicates a potential risk has been detected. In this case, treatment should be stopped immediately to protect patient safety, and the operator should be guided to intervene and eliminate the risk. Specifically, the control system can send a command to the boron neutron capture therapy device to stop the neutron beam output and simultaneously display a clear warning message on the operating interface, instructing the operator to check the sensor status, patient position, or re-execute the aforementioned positioning verification procedure. Furthermore, the system can automatically record fault logs and provide diagnostic tools to help operators quickly locate the cause of the problem, such as indicating which sensor's data is abnormal.

[0112] By synchronously acquiring and rigorously redundant-checking the three types of key location data mentioned above, this proactive, multi-sensor fusion-based verification method can promptly detect potential errors or malfunctions in a single sensor, preventing treatment position deviations from being corrected due to data inconsistencies. It also provides operators with timely intervention opportunities, avoids potential medical accidents, and constructs a more reliable and safe treatment environment.

[0113] It should be noted that the collection, gathering, updating, analysis, processing, use, transmission, and storage of user personal information involved in the technical solutions provided in the embodiments of the present invention all comply with the provisions of relevant laws and regulations, are used for legitimate purposes, and do not violate public order and good morals. Necessary measures are taken to prevent unauthorized access to user personal information data and to safeguard user personal information security, network security, and national security.

[0114] In this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A positioning system for aligning and fixing a radiotherapy beam, characterized in that, include: Supporting device, placement motion device, placement guiding device, and control device; The support device is used to support the patient; The positioning and movement device is connected to the supporting device and is used to adjust the position and tilt angle of the supporting device; The placement guidance device includes a reference positioning unit, a placement registration unit, and a real-time verification unit; The reference positioning unit is used to provide a spatial reference; the positioning and registration unit is used to acquire image data to obtain the difference between the actual position and the planned position of the patient's target area; The real-time verification unit is used to continuously monitor the patient's body surface displacement during treatment; The control system, based on the treatment plan and data from the positioning guide device, controls the positioning motion device to adjust the position and tilt angle of the support device.

2. The system according to claim 1, characterized in that, The placement system also includes a support device; the support device moves with the bearing device and is used to support the bearing device when preset conditions are met.

3. The system according to claim 1, characterized in that, Multiple sets of six-dimensional force sensors or six-dimensional torque sensors are connected in series between the end flange of the positioning motion device and the interface of the bearing device; the six-dimensional force sensors or six-dimensional torque sensors are strain gauge sensors, and the strain gauges inside are arranged in an array. The six-dimensional force sensor or six-dimensional torque sensor is used to trigger the protection mode of the placement system when the contact force or torque reaches a preset threshold.

4. The system according to claim 1, characterized in that, The support device is configured as a carbon fiber composite treatment bed; Multiple sets of thin-film pressure sensors are respectively installed on the upper surface and four corners of the treatment bed board to acquire local pressure data of the bed board; multiple sets of fiber optic grating sensors are built into the carbon fiber layup of the bed board to acquire deformation data of the bed board.

5. The system according to claim 4, characterized in that, At least eight sets of the fiber Bragg grating sensors are arranged longitudinally along the bed board, and the spacing between each set of the fiber Bragg grating sensors is no more than 300 mm.

6. The system according to claim 4, characterized in that, The positioning motion device is configured as a robotic arm, and depth cameras are installed at the four corners of the bed board and at the wrist of the robotic arm. The depth cameras are used to obtain the spatial relationship between the robotic arm and the bed board and other devices to avoid collisions between the robotic arm and the bed board and other devices.

7. The system according to claim 4, characterized in that, A laser scanner is installed on the edge of the motion area of ​​the treatment bed, and the laser scanner is used to acquire the outline of an object within a preset range from the treatment bed; When the outline of an object approaching the warning range of the treatment bed is identified as a human body, an alarm mode is triggered.

8. A placement method for the system as described in claims 1-7, characterized in that, The method includes: Step 1: Obtain the patient's theoretical treatment position through the treatment plan. Based on the theoretical treatment position, the control system controls the reference positioning unit to project a positioning grid onto the treatment bed surface to assist in patient positioning. Step 2: The target treatment pose of the robotic arm is obtained through the treatment plan. The control system pre-simulates the motion path of the robotic arm in a virtual three-dimensional environment based on the target treatment pose to detect the collision risk between the robotic arm and the treatment bed and obstacles. Step 3: If there is no risk of collision on the pre-simulated path of the robotic arm, the control system controls the robotic arm to move according to the pre-simulated path; Step 4: Control the positioning and registration unit to collect positioning reference data of the patient's target area and perform image registration with the digital reconstructed image of the treatment plan to obtain the positional deviation between the actual position and the planned position of the patient's target area. Step 5: Based on the difference between the actual position and the planned position, the robotic arm adjusts the posture of the treatment bed until the difference between the actual position and the planned position is not greater than a preset allowable threshold. Step 6: Collect and reconstruct the three-dimensional point cloud of the patient's body surface through the real-time verification unit, and define the three-dimensional point position of the body surface as the body surface reference benchmark for real-time monitoring of the patient's body surface displacement.

9. The method according to claim 8, characterized in that, Following step 6, the following is also included: Real-time monitoring of the patient's real-time displacement relative to the aforementioned body surface reference baseline; When the real-time displacement of the body surface is greater than 2 mm and the duration is longer than the preset duration, the boron neutron capture therapy device is controlled by the control system to stop the neutron beam output. Within a preset time window, the patient's body surface displacement is checked to see if it returns to a baseline range of less than or equal to 2 mm; If the patient's body surface displacement cannot return to the reference range, the control system re-executes steps 4 to 6.

10. The method according to claim 8, characterized in that, Following step 6, the method further includes: The control system synchronously acquires the actual pose feedback from the encoder of the robotic arm, the image registration result of the positioning and registration unit, and the three-dimensional point cloud data of the body surface collected by the real-time verification unit. Redundancy position verification is performed on the three. If the translational deviation between any two is greater than 1 mm or the attitude rotation deviation is greater than 0.5°, the redundancy position verification is deemed to have failed. If the redundant position verification fails, the control system stops the treatment process and prompts for re-verification.

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