Collimator and control system thereof

Abstract

The invention discloses a collimator and a control system thereof, the collimator comprises at least one grating assembly, each grating assembly comprises a plurality of grating blades, and the grating blades are used for blocking beam current; the control system comprises a third adjusting device, wherein the third adjusting device comprises a third grating encoder, a fourth grating encoder and a plurality of third adjusting units; each third adjusting unit is in driving connection with one grating blade, and the third grating encoder and the fourth grating encoder are connected with the grating blades; and the control module is connected with the plurality of third adjusting units through a CANBUS bus, and is configured to adjust the position of each grating blade according to a main feedback signal acquired by the third grating encoder and a secondary feedback signal acquired by the fourth grating encoder so as to adjust the shape of the proton beam and enable the proton beam to be matched with the shape of a tumor. According to the collimator and the control system thereof, the positions of the grating blades can be adjusted in real time according to feedback signals, and it is ensured that the proton beam is efficiently and dynamically adjusted.

Description

Technical Field

[0001] The present invention relates to the technical field of high-end medical equipment, and in particular to a collimator and a control system thereof. Background Art

[0002] Proton therapy is an advanced radiotherapy technology that leverages the Bragg peak characteristics of proton beams to precisely target tumor tissue while minimizing damage to surrounding healthy tissue. Compared to traditional X-ray radiotherapy, proton therapy offers greater dose distribution accuracy, delivering the maximum dose to the tumor while rapidly decreasing the dose to healthy tissues in front and behind the tumor, significantly reducing radiation damage to normal tissue. This characteristic makes proton therapy particularly suitable for treating tumors located near critical organs or tissues, such as brain tumors, eye tumors, and pediatric tumors.

[0003] The high precision requirements of proton therapy also bring technical challenges. In order to give full play to the Bragg peak characteristics of the proton beam, it is necessary to ensure that the shape and position of the proton beam can accurately match the shape and position of the tumor. The collimator is one of the key components in the proton therapy equipment. Its main function is to adjust the shape of the proton beam to match the shape of the tumor. Through the collimator, the proton beam can be accurately guided to the tumor area while avoiding damage to the surrounding healthy tissue. Traditional collimators usually use a fixed grating system, and the position of the grating blades is adjusted manually or semi-automatically to form beams of different shapes. In order to further improve the collimator, the present invention proposes a new collimator and its control system. Summary of the Invention

[0004] The object of the present invention is to provide a collimator and a control system thereof, which can adjust the position of the grating blades in real time according to the feedback signal, so as to ensure that the shape of the proton beam is dynamically adjusted as the shape of the tumor changes.

[0005] The purpose of the present invention is achieved by the following technical solutions:

[0006] In one aspect, the present invention provides a control system for a collimator, wherein the collimator comprises at least one grating assembly, each of the grating assembly comprises a plurality of grating blades, and the grating blades are used to block a beam;

[0007] The control system includes:

[0008] A third adjustment device, comprising a third grating encoder, a fourth grating encoder, and a plurality of third adjustment units; each of the third adjustment units is driven and connected to one of the grating blades, and the third grating encoder and the fourth grating encoder are connected to the grating blades;

[0009] A control module is connected to the plurality of third adjustment units via a CANBUS bus and is configured to adjust the position of each grating blade according to a primary feedback signal acquired by the third grating encoder and a secondary feedback signal acquired by the fourth grating encoder, so as to adjust the shape of the proton beam to match the shape of the tumor.

[0010] The beneficial effect of the above solution is that the present invention can adjust the position of the grating blades in real time based on feedback signals, ensuring that the shape of the proton beam dynamically adjusts as the tumor changes. Specifically, using dual feedback signals from the third and fourth grating encoders, the control system can precisely adjust the position of the grating blades, ensuring that the shape of the proton beam closely matches the tumor shape, thereby improving treatment accuracy. Furthermore, the present invention can connect multiple third adjustment units via a CANBUS bus, making the system modular and easy to expand and maintain.

[0011] Furthermore, the third adjustment unit drives the grating blades to move back and forth along the C-axis direction;

[0012] The control system further comprises:

[0013] a first adjusting device, the first adjusting device driving the grating assembly to move back and forth along the A-axis;

[0014] a second adjustment device, the second adjustment device driving the collimator to move back and forth along the B-axis;

[0015] The A-axis is perpendicular to the B-axis and the C-axis, and the B-axis and the C-axis intersect.

[0016] The beneficial effect of the above solution is that, through three-axis motion control (A, B, and C), the system can achieve multi-dimensional adjustment of the grating assembly and blades, ensuring that the shape of the proton beam closely matches the tumor shape. Furthermore, by moving the blades along the C axis and the grating assembly along the A and B axes, the system can adapt to tumors of varying shapes and locations, enhancing treatment flexibility.

[0017] Furthermore, the third adjustment unit includes a third linear motor, and the third linear motor is connected to the grating blades;

[0018] Furthermore, the first adjustment device includes a first rotary motor, a first rotary encoder and a first grating encoder, the first rotary encoder is connected to the first rotary motor, the first rotary motor is connected to the grating assembly, and the first grating encoder is connected to the grating assembly;

[0019] Furthermore, the second adjustment device includes a second rotary motor, a second rotary encoder and a second grating encoder, the second rotary encoder is connected to the second rotary motor, the second rotary motor is connected to the grating assembly, and the second grating encoder is connected to the grating assembly.

[0020] The beneficial effects of the above solution are as follows: the present invention utilizes a rotary motor to drive the grating assembly through the first and second adjustment devices to adjust the position of the grating blades, and a linear motor to drive the grating blades through the third adjustment unit to further adjust the position of the grating blades. Furthermore, through dual feedback from the rotary encoder and the grating encoder, the system achieves high-precision position control, ensuring the accurate positioning of the grating blades.

[0021] Furthermore, the control module is connected to the first rotary motor, the second rotary motor and / or the third linear motor via a CANBUS bus;

[0022] Furthermore, the control module is further configured to: adjust the position of each grating component according to the primary feedback signal collected by the first grating encoder and the secondary feedback signal collected by the first grating encoder;

[0023] Furthermore, the control module is further configured to adjust the position of each grating component according to the primary feedback signal collected by the second grating encoder and the secondary feedback signal collected by the second grating encoder.

[0024] The beneficial effects of the above solution are as follows: The present invention achieves centralized control by connecting the first rotary motor, the second rotary motor, and the third linear motor via a CANBUS bus, ensuring synchronous and coordinated multi-axis motion. Furthermore, the control module adjusts the position of the grating assembly based on feedback signals from the first and second grating encoders, ensuring high-precision control of the system.

[0025] Furthermore, the control module includes:

[0026] An FPGA unit, wherein the FPGA unit is connected to each encoder;

[0027] A microprocessor, one end of which is connected to the FPGA unit, and the other end of which is connected to the CANBUS bus.

[0028] The beneficial effect of the above solution is that, through the combination of an FPGA unit and a microprocessor, the present invention can quickly process encoder feedback signals, ensuring that the system responds to changes in the position of the grating blades and grating assembly in real time. In addition, the CANBUS bus connects the motors and encoders, resulting in a highly integrated system that is easy to expand and maintain.

[0029] Furthermore, the control module is further configured to:

[0030] Obtain the shape of the tumor;

[0031] Based on TPS, a treatment plan is generated according to the shape of the tumor;

[0032] Based on the LPA, the positions of the grating blades are adjusted according to the treatment plan.

[0033] The beneficial effects of this approach include generating personalized treatment plans based on tumor shape, ensuring a precise match between the proton beam and the tumor, and enhancing treatment effectiveness. Furthermore, based on the TPS (Treatment Planning System) and LPA (Leaf Positioning Algorithm), the system automatically adjusts the position of the grating blades, reducing manual intervention and improving treatment efficiency.

[0034] Furthermore, the treatment plan includes a TPS dynamic trajectory;

[0035] The adjusting the position of the grating blades according to the treatment plan includes:

[0036] The current positions of multiple grating blades are fitted into a blade curve, and the grating blades are moved so that the blade curve coincides with the TPS dynamic trajectory.

[0037] The beneficial effect of this solution is that by fitting the current position of the grating blades to a blade curve and aligning it with the dynamic trajectory of the TPS, the system can dynamically adjust the proton beam shape, ensuring treatment precision. Furthermore, the motion path of the grating blades is optimized to achieve the treatment goal with minimal blade movement, reducing system energy consumption and mechanical wear.

[0038] Furthermore, the plurality of grating blades are arranged in sequence, the grating blades at both ends of the grating assembly are first blades, and the grating blades in the middle of the grating assembly are second blades;

[0039] The movable grating blades include:

[0040] The first blade is moved first, and then the second blade is moved, so that the grating blades of the plurality of grating components are sequentially surrounded by a closed blade curve, and the closed blade curve coincides with the TPS dynamic trajectory.

[0041] The beneficial effect of this solution is that by first moving the first blades at the ends of the grating assembly, followed by the second blade in the middle, the system can efficiently form a closed blade curve, ensuring that the shape of the proton beam closely matches the shape of the tumor. Furthermore, by optimizing the sequence of blade movement, the system can reduce internal blade movement, thereby reducing mechanical wear and energy consumption.

[0042] Furthermore, the movable grating blades include:

[0043] Based on PID control algorithm and feedforward control algorithm, the thrust is adjusted to compensate for mechanical load disturbance;

[0044] The PID control algorithm is used to adjust the motor current according to the difference between the actual position of the grating blade and the target position, so that the grating blade moves to the target position;

[0045] The feedforward control algorithm is used to apply thrust before the grating blades move, thereby offsetting inertia, friction and gravity interference during the movement of the grating blades.

[0046] The beneficial effects of the above solution are: through the use of PID control algorithms and feedforward control algorithms, the system can dynamically adjust thrust, compensate for mechanical load disturbances, and ensure that the grating blades move quickly and accurately to the target position. In addition, the feedforward control algorithm can offset inertia, friction, and gravity interference, ensuring that the grating blades remain stable during movement.

[0047] Furthermore, the control system further includes a safety circuit, which includes:

[0048] Hardware emergency stop circuit, used to stop the operation of the adjustment device in an emergency;

[0049] Overcurrent protection circuit, used to cut off the power supply when the motor current exceeds the set threshold;

[0050] Over-temperature protection circuit, used to automatically stop the adjustment device when the motor temperature exceeds the set threshold;

[0051] The software protection circuit is used to limit the motion range of the grating blades through the position soft limit function to prevent collision or over-limit movement.

[0052] The beneficial effects of the above solution are: through hardware emergency stop, overcurrent protection, overtemperature protection, and software protection, the system can immediately stop operation in an emergency, preventing equipment damage and personal injury. In addition, the position soft limit function can limit the motion range of the grating blades, preventing collisions or excessive movement, and ensuring safe operation of the equipment.

[0053] Furthermore, the control system further includes:

[0054] A self-diagnostic circuit monitors the motor coil impedance, motor temperature, and motor vibration spectrum in real time.

[0055] The beneficial effects of this solution are: by real-time monitoring of motor coil impedance, temperature, and vibration spectrum, the self-diagnostic circuit can predict motor faults (such as bearing wear and coil aging), allowing proactive measures to prevent equipment damage. Furthermore, the self-diagnostic circuit can trigger an alarm or shut down the system when an anomaly is detected, ensuring safe system operation and reducing downtime.

[0056] In a second aspect, the present invention provides a collimator for use in a proton therapy device;

[0057] The collimator includes the above-mentioned control system.

[0058] The beneficial effect of the above scheme is that the present invention can adjust the position of the grating blades in real time according to the shape and position of the tumor through the adaptive collimator of the proton therapy equipment, ensuring that the shape of the proton beam is highly matched with the shape of the tumor, thereby improving the accuracy of treatment.

[0059] Compared with the prior art, the beneficial effects of the present invention include at least:

[0060] The present invention can adjust the position of the grating blades in real time based on feedback signals, ensuring that the shape of the proton beam dynamically adjusts as the tumor changes. Specifically, through dual feedback signals from the third and fourth grating encoders, the control system can precisely adjust the position of the grating blades, ensuring that the shape of the proton beam closely matches the tumor shape, thereby improving treatment accuracy. Furthermore, the present invention can connect multiple third adjustment units via the CANBUS bus, making the system modular and easy to expand and maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 The figure is a structural diagram of a control system of a collimator according to an embodiment of the present invention.

[0062] Figure 2 2 is another structural schematic diagram of a control system of a collimator according to an embodiment of the present invention.

[0063] Figure 3 It is a structural schematic diagram of an adjustment device according to an embodiment of the present invention.

[0064] Figure 4 Schematic diagram of the structure of the first blade and the second blade in an embodiment of the present invention.

[0065] In the figure: 11, first blade; 12, second blade; 13, blade curve; 14, channel; 30, second adjustment device; 41, first adjustment device; 100, third adjustment device. DETAILED DESCRIPTION

[0066] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.

[0067] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0068] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0069] The collimator of the present invention is an adaptive collimator (Adaptive Aperture, AA), which is used in proton therapy equipment to adjust the shape of the proton beam to match the shape of the tumor.

[0070] When used, the collimator includes at least one grating component. Preferably, the collimator of the present application includes two grating components arranged opposite to each other.

[0071] In practical applications, each grating assembly includes multiple grating blades, which are used to block the beam. The combination of multiple grating blades can adjust the shape of the proton beam. Furthermore, the multiple grating blades are arranged sequentially, with the grating blades at both ends of the grating assembly being the first blades 11, and the grating blades in the middle of the grating assembly being the second blades 12. Preferably, each grating assembly includes seven grating blades.

[0072] refer to Figure 3 The control system of the present invention includes: a third adjustment device 100 and a control module. Furthermore, the control system of the present invention may also include: a first adjustment device 41 and / or a second adjustment device 30. Preferably, the first adjustment device 41 is provided in one group, and the second adjustment device 30 is provided in two groups. Furthermore, the control system of the present invention may also include: a safety circuit and / or a self-diagnostic circuit.

[0073] When applying, refer to Figure 1 and Figure 2 The control system of the present invention may further include: a main control computer connected to the control module.

[0074] The third adjustment device 100 of the present invention includes a third grating encoder, a fourth grating encoder, and a plurality of third adjustment units. Preferably, the third adjustment device 100 includes two groups, and each group of the third adjustment device 100 includes seven third adjustment units.

[0075] In application, each third adjustment unit drives and connects to a grating blade, and the third grating encoder and the fourth grating encoder are connected to the grating blade. Specifically, the third grating encoder is used to collect the primary feedback signal of the grating blade, and the fourth grating encoder is used to collect the secondary feedback signal of the grating blade.

[0076] In practical applications, the third adjustment unit includes a third linear motor connected to the grating blades. Specifically, the third linear motor drives the grating blades to move back and forth along the C-axis to adjust the shape of the proton beam to match the shape of the tumor.

[0077] The first adjustment device 41 of the present invention drives the grating assembly to move back and forth along the A-axis, where the A-axis and the C-axis are perpendicular to each other.

[0078] When used, the first adjustment device 41 includes a first rotary motor, a first rotary encoder and a first grating encoder. The first rotary encoder is connected to the first rotary motor, the first rotary motor is connected to the grating assembly, and the first grating encoder is connected to the grating assembly.

[0079] The second adjustment device 30 of the present invention drives the collimator to move back and forth along the B-axis direction. The A-axis and the B-axis are perpendicular to each other, and the B-axis and the C-axis intersect.

[0080] When used, the second adjustment device 30 includes a second rotary motor, a second rotary encoder, and a second grating encoder. The second rotary encoder is connected to the second rotary motor, the second rotary motor is connected to the grating assembly, and the second grating encoder is connected to the grating assembly.

[0081] refer to Figure 1 and Figure 2 The control module of the present invention includes: an FPGA unit and a microprocessor.

[0082] During use, the FPGA unit is connected to each encoder; one end of the microprocessor is connected to the FPGA unit, and the other end of the microprocessor is connected to the CANBUS bus. Furthermore, the microprocessor of the control module is connected to multiple third adjustment units via the CANBUS bus. Preferably, the microprocessor of the control module is connected to the first rotary motor, the second rotary motor, and / or the third linear motor via the CANBUS bus, and to each motor and encoder via the CANBUS bus, resulting in a highly integrated system that is easy to expand and maintain.

[0083] In practical applications, the collimator control method includes: a control module collects feedback signals from each grating encoder in real time and dynamically adjusts the motion state of each motor based on the feedback signals to ensure that the grating blades accurately move to the target position. Furthermore, the control module calculates the error between the actual position of the grating assembly and the target position based on the primary and secondary feedback signals. Then, based on the position error, the current of the first rotary motor, the second rotary motor, and / or the third linear motor is adjusted to drive the grating assembly along the A-axis, the B-axis, and / or the grating blades along the C-axis to the target position.

[0084] Preferably, the control module is configured to perform the following steps: adjusting the position of each grating blade according to the primary feedback signal collected by the third grating encoder and the secondary feedback signal collected by the fourth grating encoder; adjusting the position of each grating component according to the primary feedback signal collected by the first grating encoder and the secondary feedback signal collected by the first grating encoder; adjusting the position of each grating component according to the primary feedback signal collected by the second grating encoder and the secondary feedback signal collected by the second grating encoder.

[0085] In some other embodiments, the control module is further configured to execute steps SS1 to SS3. Specifically, a personalized treatment plan is generated based on the shape of the tumor, ensuring that the shape of the proton beam closely matches the tumor shape, thereby improving treatment efficacy. Furthermore, based on the TPS (Treatment Planning System) and LPA (Leaf Positioning Algorithm), the system can automatically adjust the position of the grating blades, reducing manual intervention and improving treatment efficiency.

[0086] Step SS1: Obtain the shape of the tumor.

[0087] When applied, the shapes of tumors in different organs are generally different, and the shapes of tumors in different stages are generally different as well.

[0088] Step SS2: Based on TPS (treatment planning system), a treatment plan is generated according to the shape of the tumor.

[0089] When applied, a treatment plan is generated based on TPS (treatment planning system) to determine the target position of the grating blades.

[0090] Step SS3: Based on the LPA (Leaf Positioning Algorithm), adjust the positions of the grating blades according to the treatment plan, wherein the treatment plan includes the TPS dynamic trajectory.

[0091] When used, step SS3 involves coarse adjustment, which involves planning the motion paths of the grating blades based on the LPA (Blade Positioning Algorithm) to ensure the accuracy and efficiency of multi-axis coordinated motion. Specifically, the control module sends control commands via the CANBUS bus to ensure the synchronous movement of the first rotary motor, the second rotary motor, and the third linear motor to avoid collisions and over-limit motion.

[0092] In some preferred embodiments, step SS3 includes: fitting the current positions of the plurality of grating blades into a blade curve 13, and moving the grating blades so that the blade curve coincides with the TPS dynamic trajectory.

[0093] Initialize the grating blade positions, ensuring that all blades are in their initial positions, and load the TPS dynamic trajectory data. Next, the control system uses an interpolation algorithm to fit the current positions of multiple grating blades into a continuous blade curve based on the current blade positions. The fitted blade curve is compared with the TPS dynamic trajectory and the deviation between the two is calculated.

[0094] When applying, refer to Figure 4 , the step of moving the grating blades includes a fine adjustment step. The fine adjustment step includes: by optimizing the order of blade movement, the system can reduce the movement of internal blades, reduce mechanical wear and energy consumption. Specifically: first move the first blade, then move the second blade, so that the grating blades of the multiple grating components more quickly form the expected closed blade curve, and the internal space enclosed by the blade curve is the space allowing the proton beam to pass through, namely, channel 14. The closed blade curve of the present invention coincides with the TPS dynamic trajectory, ensuring that the shape of the proton beam is highly matched with the shape of the tumor.

[0095] Based on the deviation calculation results, the position of the first blade is first adjusted to be as close as possible to the starting point of the TPS trajectory. While keeping the first blade's position unchanged, the position of the second blade is adjusted so that the grating curve formed by it and the first blade coincides with the next segment of the TPS trajectory. Subsequent blades are adjusted in sequence, ensuring that each blade's movement is based on the position of the previous blade, until the closed curve formed by all blades completely coincides with the TPS dynamic trajectory.

[0096] In practical applications, the adjustment process for moving the grating blades involves the following steps: The thrust is adjusted to compensate for mechanical load disturbances based on a PID control algorithm and a feedforward control algorithm. The PID control algorithm adjusts the motor current based on the difference between the actual and target positions of the grating blades to move them to the target position. The feedforward control algorithm applies thrust before the grating blades move to offset inertia, friction, and gravity during movement.

[0097] In some embodiments, the required inertia compensation torque is calculated based on the motor's mass and acceleration requirements. Before the motor starts, a corresponding feedforward torque command is applied to the drive system to offset the system's inertia, ensuring rapid dynamic response. This inertia compensation strategy can effectively reduce tracking error during acceleration and deceleration, improving the servo system's transient response.

[0098] In some other embodiments: a composite control strategy is adopted in combination with feedforward compensation and electromagnetic preload technology to achieve millisecond-level dynamic response. The specific implementation method includes the following steps: using a dual-winding electromagnetic actuator to pre-excite the compensation winding before the motion command is issued, and to establish a reverse electromagnetic field to offset the mechanical lag. The control process is: 1) according to the acceleration command given by the motion planning module, the compensation winding current reference value is calculated in real time; 2) the main drive winding and the compensation winding are synchronously excited according to the current command value; 3) after the rotor starts to move, the compensation current is linearly demagnetized using a ramp function; 4) after entering the steady-state operation stage, it is switched to a closed-loop speed control mode based on the PID algorithm. The present invention can shorten the step response time to less than 5ms by actively offsetting the influence of the system's electromechanical time constant.

[0099] In some embodiments, the required friction compensation force is calculated based on the friction characteristics of the motor (including viscous friction coefficient and Coulomb friction) and the target motion speed:

[0100] Fcomp=Fc·sgn(vref)+Bv·vref

[0101] Where Fcomp is the required friction compensation force; Fc is Coulomb friction; sgn(vref) is the sign of the velocity direction; Bv is the viscous friction coefficient; and vref is the target motion velocity. Before the motor moves, a corresponding feedforward compensation current, Icomp = Fcomp / Kt (Kt is the motor torque constant), is applied through the current loop to offset nonlinear friction during movement, ensuring low-speed smoothness and high-speed dynamic response.

[0102] In some other embodiments: nanometer-scale smooth motion is achieved through dynamic friction modeling and feedforward compensation. For example: the LuGre friction model is used to comprehensively consider static friction, Coulomb friction, viscous friction and Stribeck effect. Specifically, the friction characteristics of the motor are measured to determine the viscous friction coefficient and the Coulomb friction coefficient; the viscous friction compensation force and the Coulomb friction compensation force are calculated according to the target motion speed; the compensation force is converted into a feedforward current and applied through the current loop; when the speed passes through zero, a high-frequency micro-dither signal is superimposed to reduce the hysteresis effect caused by static friction; based on the position / speed feedback, the feedforward gain is adjusted online to ensure nanometer-scale motion smoothness.

[0103] In some embodiments, the required gravity compensation force is calculated based on the mass of the motor and the acceleration of gravity; before the position command is issued, an equivalent compensation current is applied through the feedforward channel of the servo drive, that is, before the motor moves, the corresponding feedforward thrust is applied to offset the influence of gravity when the motor moves in the vertical direction, ensuring that the motor can accurately control the position.

[0104] In some other embodiments, full gravity compensation is achieved through pneumatic balancing cylinders and model feedforward. Specifically, upon power-up, a proportional valve adjusts the pressure in the upper and lower chambers of the balancing cylinder to a balanced value. A high-speed solenoid valve switches the air path based on the motion command direction. The compensation force is updated based on real-time data from the load sensor. A feedforward controller calculates the proportional valve compensation current. Furthermore, a pressure tolerance band is set to prevent oscillation, triggering the quick exhaust valve in an emergency stop.

[0105] In some preferred embodiments, after completing individual tuning of PID control and feedforward control, comprehensive tuning can be performed to ensure that the system achieves optimal performance in speed and position control. Specifically, the actual speed response of the motor is obtained, and the PID parameters and feedforward control parameters are adjusted to ensure that the actual speed can quickly track the target speed without significant overshoot or oscillation. The actual position response of the motor is obtained, and the PID parameters and feedforward control parameters are adjusted to ensure that the actual position can accurately track the target position without significant overshoot or oscillation.

[0106] The safety circuit of the present invention comprises: a hardware emergency stop circuit, an overcurrent protection circuit, an overtemperature protection circuit and a software protection circuit.

[0107] When applied, the hardware emergency stop circuit is used to stop the operation of the adjustment device in an emergency; the overcurrent protection circuit is used to cut off the power supply when the motor current exceeds the set threshold; the overtemperature protection circuit is used to automatically stop the operation of the adjustment device when the motor temperature exceeds the set threshold; the software protection circuit is used to limit the movement range of the grating blades through the position soft limit function to prevent collision or over-limit movement.

[0108] The self-diagnosis circuit of the present invention monitors the motor coil impedance, motor temperature and motor vibration spectrum in real time.

[0109] In summary, the present invention can adjust the position of the grating blades in real time based on feedback signals, ensuring that the shape of the proton beam dynamically adjusts as the tumor changes. Specifically, through the dual feedback signals from the third and fourth grating encoders, the control system can precisely adjust the position of the grating blades, ensuring that the shape of the proton beam closely matches the tumor shape, thereby improving the accuracy of treatment. Furthermore, the present invention can connect multiple third adjustment units via a CANBUS bus, making the system modular and easy to expand and maintain.

[0110] In some embodiments, the present invention further provides a radiotherapy device comprising the aforementioned collimator, a particle accelerator for outputting a particle beam, and one or more scanning magnets for moving the particle beam relative to the patient's irradiation target, i.e., the tumor. The particle accelerator is capable of reciprocating circumferential motion driven by a rotating gantry, with the collimator positioned between the one or more scanning magnets and the patient. In this embodiment, the collimator fits different target shapes to the channel. After passing through the collimator, the particle beam delivers radiotherapy to the patient's treated area in the designated target shape. The particles may be protons or heavy ions. The radiotherapy device may be the aforementioned proton therapy device.

[0111] An embodiment of the present invention further provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the collimator control method in the embodiment of the present invention when executing the computer program.

[0112] An embodiment of the present invention further provides a computer-readable storage medium for storing a computer program. When the computer program is executed, the steps of the aforementioned control method in the embodiment of the present invention are implemented. The specific implementation method is consistent with the implementation method and the technical effect achieved in the above-mentioned embodiment of the control method of the collimator, and some contents are not repeated here.

[0113] In the present application, a readable storage medium can be any tangible medium that contains or stores a program that can be used by or in combination with an instruction execution system, device or device. A program product can use any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared or semiconductor system, device or device, or any combination of the above. More specific examples of readable storage media (a non-exhaustive list) include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0114] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0115] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0116] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0117] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0118] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which are all protected by the present invention.

Claims

1. A collimator control system, characterized in that: The collimator includes at least one grating component, each of the grating components includes a plurality of grating blades, and the grating blades are used to block the beam; The control system includes: A third adjustment device (100), comprising a third grating encoder, a fourth grating encoder, and a plurality of third adjustment units; each of the third adjustment units is driven and connected to one of the grating blades, and the third grating encoder and the fourth grating encoder are connected to the grating blades; A control module is connected to the plurality of third adjustment units via a CANBUS bus and is configured to adjust the position of each grating blade according to a primary feedback signal collected by the third grating encoder and a secondary feedback signal collected by the fourth grating encoder to adjust the shape of the proton beam.

2. The collimator control system according to claim 1, characterized in that: The third adjustment unit drives the grating blades to move back and forth along the C-axis direction; The control system further comprises: A first adjustment device (41), the first adjustment device (41) drives the grating component to move back and forth along the A-axis direction; a second adjustment device (30), the second adjustment device (30) driving the collimator to move back and forth along the B-axis direction; The A-axis is perpendicular to the B-axis and the C-axis, and the B-axis and the C-axis intersect.

3. The collimator control system according to claim 2, characterized in that: The third adjustment unit includes a third linear motor, and the third linear motor is connected to the grating blades; And / or, the first adjustment device (41) comprises a first rotary motor, a first rotary encoder and a first grating encoder, the first rotary encoder is connected to the first rotary motor, the first rotary motor is connected to the grating assembly, and the first grating encoder is connected to the grating assembly; And / or, the second adjustment device (30) includes a second rotary motor, a second rotary encoder and a second grating encoder, the second rotary encoder is connected to the second rotary motor, the second rotary motor is connected to the grating assembly, and the second grating encoder is connected to the grating assembly.

4. The collimator control system according to claim 3, characterized in that: The control module is connected to the first rotary motor, the second rotary motor and / or the third linear motor via a CANBUS bus; And / or, the control module is further configured to: adjust the position of each grating component according to the primary feedback signal collected by the first grating encoder and the secondary feedback signal collected by the first grating encoder; And / or, the control module is further configured to adjust the position of each grating component according to the primary feedback signal collected by the second grating encoder and the secondary feedback signal collected by the second grating encoder.

5. The collimator control system according to claim 3, characterized in that: The control module includes: An FPGA unit, wherein the FPGA unit is connected to each encoder; A microprocessor, one end of which is connected to the FPGA unit, and the other end of which is connected to the CANBUS bus.

6. The collimator control system according to claim 3, characterized in that: The control module is further configured to: Obtain the shape of the tumor; Based on TPS, a treatment plan is generated according to the shape of the tumor; Based on the LPA, the positions of the grating blades are adjusted according to the treatment plan.

7. The collimator control system according to claim 6, characterized in that: The treatment plan includes a TPS dynamic trajectory; The adjusting the position of the grating blades according to the treatment plan includes: The current positions of multiple grating blades are fitted into a blade curve, and the grating blades are moved so that the blade curve coincides with the TPS dynamic trajectory.

8. The collimator control system according to claim 7, characterized in that: The plurality of grating blades are arranged in sequence, the grating blades at both ends of the grating component are first blades, and the grating blades in the middle of the grating component are second blades; The movable grating blades include: The first blade is moved first, and then the second blade is moved, so that the grating blades of the plurality of grating components form a closed blade curve, and the closed blade curve coincides with the TPS dynamic trajectory.

9. The collimator control system according to claim 7, characterized in that: The movable grating blades include: Based on PID control algorithm and feedforward control algorithm, the thrust is adjusted to compensate for mechanical load disturbance; The PID control algorithm is used to adjust the motor current according to the difference between the actual position of the grating blade and the target position, so that the grating blade moves to the target position; The feedforward control algorithm is used to apply thrust before the grating blades move, thereby offsetting inertia, friction and gravity interference during the movement of the grating blades.

10. The collimator control system according to claim 1, characterized in that: The control system further includes a safety circuit, which includes: Hardware emergency stop circuit, used to stop the operation of the adjustment device in an emergency; Overcurrent protection circuit, used to cut off the power supply when the motor current exceeds the set threshold; Over-temperature protection circuit, used to automatically stop the adjustment device when the motor temperature exceeds the set threshold; The software protection circuit is used to limit the motion range of the grating blades through the position soft limit function to prevent collision or over-limit movement.

11. The collimator control system according to claim 3, characterized in that: The control system further comprises: A self-diagnostic circuit monitors the motor coil impedance, motor temperature, and motor vibration spectrum in real time.

12. A collimator, characterized in that: For proton therapy equipment; The collimator comprises: the control system according to any one of claims 1 to 11.

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