A control system for a wedge energy reducer

Abstract

A control system for a wedge-shaped energy degrader includes a system board, a motion board, a stepper motor driver, a stepper motor, and the wedge-shaped energy degrader. This control system ensures that the energy degradation response time for each level of the energy degrader is faster than that of a multi-wedge energy degrader, completing energy switching within 50 milliseconds. The wedge-shaped energy degrader comprises a pair of angled wedge-shaped graphite energy degrading sheets. The length or distance traveled by the pair of angled wedge-shaped energy degraders is several times that of the multi-wedge energy degrader or the distance traveled by the multi-wedge energy degraders, and their width is the same as the sum of the widths of the multi-wedge energy degraders. This invention organically combines DDS communication, a VxWorks embedded real-time control system, and an S-curve algorithm module, solving the problem that the increased size of existing wedge-shaped energy degraders, resulting in a length or distance traveled several times greater than that of multi-wedge energy degraders and a significantly slower response time, is a major drawback.

Description

Technical Field

[0001] This invention belongs to the technical field of proton therapy systems, and particularly relates to a control system for a wedge-shaped energy degrader. Background Technology

[0002] In proton radiotherapy devices, to apply the proton cyclotron accelerator clinically, a proton beam energy selective control system must be used to adjust the extracted proton beam energy according to the different depths and thicknesses of the tumor. This proton beam energy selective control system includes: energy degraders, multiple magnets, multiple four-fan collimators, momentum selective slits, energy selective slits, motion control boards, and system boards, etc., arranged along the path from the beamline starting point (the beam is drawn from the accelerator outlet, passes through a set of quadrupole magnets and guide magnets) to the target point (the rotating gantry connected to the treatment head).

[0003] The challenge in implementing a proton energy selective control system lies in the fact that existing de-energizers cannot simultaneously meet the requirements of fast response speed and avoiding beam energy loss. The first type, the multi-wedge de-energizer, while meeting the energy reduction speed requirement, suffers from significant beam energy loss. This is because the multi-wedge de-energizer uses multiple relatively small (short width and length) wedge-shaped de-energizers arranged side-by-side. Its fast response is achieved through its relatively short length or path, and the side-by-side arrangement meets the de-energizer thickness requirement. Only when the de-energizer thickness meets the requirement can the maximum energy reduction range be achieved. However, because it involves multiple wedge-shaped de-energizers arranged side-by-side with multiple air gaps, energy loss occurs every time the beam passes through an air gap. This results in multiple energy losses when passing through multiple sets of wedge-shaped de-energizers. Another existing technology is the double-wedge airfoil beryllium de-energizer. While this reduces beam loss issues associated with multi-wedge de-energizers, beryllium is toxic and generates a large number of neutrons, increasing the difficulty of radiation protection. Furthermore, although this double-wedge airfoil de-energizer reduces energy loss by converting multiple double-wedge airfoils into a single one, the overall volume increases significantly. Replacing multiple double-wedge airfoils with a single one not only increases the thickness but also the length or travel distance, increasing several times over. This increased length or travel distance leads to a several-fold slower response time. Since the de-energizer is the first device in the proton beam energy selective control system, if the first device's response time is delayed, and the proton therapy system controls the beamline equipment using a serial command method, the delay time of the entire beamline will be even more severe. Summary of the Invention

[0004] This invention addresses the shortcomings of existing technologies by proposing a control system for a wedge-shaped de-energizer. The purpose is to solve the problem that the increased size of existing wedge-shaped de-energizers, which increases their length or travel distance by several times compared to multi-wedge de-energizers, leads to a significant slowdown in the de-energizer's response time.

[0005] To address the problems existing in the prior art, the present invention proposes the following technical solution:

[0006] A control system for a wedge-shaped deflector, belonging to a proton beam energy selection control system, is disclosed. This control system controls a wedge-shaped deflector located after the beam exit of a proton therapy beamline accelerator, passing through a set of quadrupole magnets and a guide magnet. The control system includes a system board, a motion board, a stepper motor driver, a stepper motor, and the wedge-shaped deflector. The system board's input is connected to the treatment head and communicates with it via a DDS (Digital Data System), while its output is connected to the motion board. The stepper motor driver's input is connected to the motion board, and its output is connected to the stepper motor. The stepper motor's input is connected to the stepper motor driver, and its output is connected to the wedge-shaped deflector.

[0007] Its features are: the energy reduction response time of the paired wedge energy reducer control system is faster than that of the multi-wedge energy reducer, and can complete the energy switching within 50 milliseconds; the paired wedge energy reducer includes a pair of wedge-shaped graphite energy reducing plates with tilt angles, the length or distance traveled by the pair of wedge-shaped graphite energy reducing plates with tilt angles is several times the length or distance traveled by the multi-wedge energy reducing plates, and the width is the same as the sum of the widths of the multi-wedge energy reducing plates.

[0008] Furthermore, the system board is equipped with a VxWorks embedded real-time control system for sending and reading relevant signals.

[0009] Furthermore, the stepper motor driver is provided with a motion board interface for an external motion board. The motion information of the relevant stepper motor can be obtained from the motion board through the motion board interface to ensure that the energy switching time is within 50ms each time. The motion information includes the number of steps, motion speed, and motion acceleration that ensure the corresponding time of 50ms.

[0010] Furthermore, the stepper motor driver also obtains S-curve parameter information for controlling the stepper motor's motion from the motion board, including S-curve acceleration parameters, deceleration parameters, and uniform motion parameters. The S-curve parameters are used to control the smooth rise of the stepper motor's acceleration from the lowest point to the highest point, and to control the smooth fall of the stepper motor's deceleration from the highest point to the lowest point.

[0011] Furthermore, the system board includes a multi-task scheduling unit and a lookup table unit; the lookup table unit is equipped with an energy degrader lookup table submodule, which performs a lookup table based on the treatment head beam energy value obtained by the system board, thereby obtaining the number of steps, movement speed, and movement acceleration of the energy degrader stepper motor that can complete energy switching within 50 milliseconds. The lookup table unit then sends these parameters to the multi-task scheduling unit of the system board, which sends the number of steps, movement speed, and movement acceleration of the energy degrader to the stepper motor driver through the motion board.

[0012] Furthermore, the multi-task scheduling unit is provided with an energy degrader task module, which is provided with an initialization task submodule. The initialization task submodule includes calling the S-curve algorithm module, which includes setting the S-curve parameters submodule. The S-curve parameter submodule sets the four acceleration parameters, four deceleration parameters, and uniform motion parameters of the S-curve.

[0013] Furthermore, the wedge-shaped energy reducer includes a wedge-shaped energy reducer plate, an incident collimator, an exit collimator, an electronic ruler, a stepper motor, a stepper motor driver, and a support frame. The wedge-shaped energy reducer plate is mounted vertically on the support frame at a certain angle. The wedge-shaped energy reducer plate is formed by connecting a pair of wedge-shaped graphite energy reducer plates with an inclination angle via a screw nut and a screw, with a gap between the wedge-shaped graphite energy reducer plates. The beam passes through the wedge-shaped graphite energy reducer in a direction perpendicular to the gap. The incident collimator and the exit collimator are arranged along the beam direction on the support frame on both sides of the wedge-shaped energy reducer plate. On the support frame, its height is the height of the beamline center point; the electronic ruler is installed on one side of the wedge-shaped energy reduction plate on the support frame, and reads and displays the displacement of the wedge-shaped energy reduction plate as it moves; the stepper motor is connected to the wedge-shaped energy reduction plate through a cross-slider coupling and a right-hand ball screw, driving the wedge-shaped energy reduction plate to increase or decrease its thickness; the stepper motor driver's input end is connected to the motion board, and its output end is connected to the stepper motor; the universal joint and lead screw include a right-hand ball screw and a left-hand ball screw, with a universal joint in the middle.

[0014] Furthermore, the pair of wedge-shaped graphite energy reducing sheets with tilt angles, each wedge-shaped graphite energy reducing sheet has a tilt angle of 12°, a thickness of 40mm, a top corner width of 1mm, a bottom side width of 100mm, and a length of 500mm; the maximum width of the pair of wedge-shaped energy reducing sheets during relative movement is 200mm, and the minimum width is 6mm.

[0015] Furthermore, the wedge-shaped energy-reducing plate includes a right energy-reducing plate and a left energy-reducing plate; the right energy-reducing plate is connected to a right-hand screw nut, which in turn is connected to a right-hand ball screw; the left energy-reducing plate is connected to a left-hand screw nut, which in turn is connected to a left-hand ball screw. The stepper motor is connected to a cross-slider coupling, which in turn connects to the right-hand ball screw for rotation. The right-hand ball screw drives the universal joint, which in turn drives the left-hand ball screw to rotate. The left-hand ball screw drives the left energy-reducing plate to move through the left-hand screw nut, thereby enabling the stepper motor to drive the left and right energy-reducing plates to move in opposite directions or in opposite directions.

[0016] Advantages and effects of the present invention

[0017] 1. This invention connects the energy degrader stepper motor driver to a motion board, the motion board to a system board, installs a VxWorks embedded real-time control system within the system board, establishes DDS communication between the system board and the treatment head, sets up an energy degrader task module on the system board, sets up an initialization call submodule within the energy degrader task module, and the initialization call submodule calls the S-curve algorithm module. Then, by setting four acceleration parameters, four deceleration parameters, and motion parameters of the S-curve algorithm module, these parameters are transmitted to the energy degrader driver via the motion board. The energy degrader driver then controls the energy degrader stepper motor, ultimately achieving a 50-millisecond energy shifting time for the energy degrader. Although the length or distance traveled by the wedge-shaped energy degrader in this invention is five times that of the multi-wedge energy degrader, the 50-millisecond energy response time is 1.2 times faster than the 60-millisecond time of the multi-wedge energy degrader. Furthermore, by using a pair of wedge-shaped energy degraders instead of the traditional multiple pairs of wedge-shaped energy degraders, the problem of beam energy loss caused by the beam passing through multiple pairs of wedge-shaped energy degraders is completely solved.

[0018] 2. This invention organically combines DDS communication, a VxWorks embedded real-time control system, and an S-curve algorithm module, solving the problem that existing wedge-shaped energy degraders, due to their increased size, have several times longer lengths or traveled distances compared to multi-wedge energy degraders, resulting in significantly slower response times. Using DDS communication saves the handshake time required between communicating parties; employing the VxWorks embedded real-time control system shortens the switching time for each task and ensures timely feedback from external devices; and calling the S-curve algorithm module eliminates concerns about potential damage to the stepper motor due to increased speed and high inertia during rapid 50-millisecond switching of large-volume wedge-shaped energy degraders. Attached Figure Description

[0019] Figure 1 This is a network topology diagram of the proton beam energy selection control system of the present invention;

[0020] Figure 2This is a functional architecture diagram of the proton beam energy selection control system of the present invention;

[0021] Figure 3 This is a schematic diagram of the lookup table unit of the wedge-shaped energy reducer control system of the present invention;

[0022] Figure 4 This is a schematic diagram of the multi-task scheduling unit of the wedge-shaped energy reducer control system of the present invention;

[0023] Figure 5 A schematic diagram illustrating the speed variation of a stepper motor under the S-curve algorithm;

[0024] In the diagram, during the time interval 0-t1, the stepper motor performs variable acceleration motion, with the acceleration first increasing and then decreasing; during the time interval t1-t2, it moves at a constant speed of v0; during the time interval t2-t3, the stepper motor performs variable deceleration motion, with the deceleration first increasing and then decreasing.

[0025] Figure 6-1 This is a schematic diagram of the energy reducer structure of the present invention;

[0026] Figure 6-2 A schematic diagram showing the connection between the left-hand and right-hand ball screws of the energy reducer via a universal joint;

[0027] In the diagram: 1: Energy reducer; 1-1: Left energy reducer; 1-2: Right energy reducer; 1-1; 1-3: Incident collimator; 1-4: Outgoing collimator; 1-5: Linear displacement sensor; 1-6: Pointer and slider; 1-7: Scale; 1-8, 1-9: Slide rail; 1-10: Left-hand ball screw; 1-11: Right-hand ball screw; 1-12: Universal joint; 1-13, 1-14: Limit switch; 1- 15 is the limit switch contact; 1-16: cross slider coupling; 1-17: stepper motor; 1-18, 1-19: support frame; 1-20: stepper motor driver; 1-21: motion control board; 1-22: treatment head; 2, 4, 5, 7, 8, 9, 10: magnets; 3, 11: collimator; 6: momentum selection slit; 12: motion control board; 13: system board; 14 is the host computer. Detailed Implementation

[0028] Design principle of this invention:

[0029] 1. Design Goals and Problems Solved: The design goal is to achieve an 80-millisecond energy switching time requirement. The problem to be solved is that when using a wedge-shaped de-energizer instead of a multi-wedge de-energizer (to avoid beam loss at each stage when the beam passes through the multi-wedge de-energizer), the length or travel distance of the wedge-shaped de-energizer increases several times compared to the multi-wedge de-energizer, resulting in a significantly slower response time due to the increased travel distance.

[0030] 2. Design Challenges of Wedge-Shaped Energy Degraders. The design challenge lies in how to address the issue of rapid acceleration and deceleration. The danger of rapid acceleration and deceleration lies in the fact that when the equipment has high inertia, it is prone to damage. Rapid acceleration and deceleration refer to the steep acceleration and deceleration of the stepper motor. This invention needs to compensate for the energy switching time delay caused by the long distance by increasing the motor speed. However, if not handled properly, rapid acceleration and deceleration can lead to equipment damage. Traditional multi-wedge-shaped energy degraders do not involve rapid acceleration and deceleration because of their small size and light weight, resulting in low inertia. In this invention, the length of the wedge-shaped energy degrader is five times that of the multi-wedge-shaped energy degrader, resulting in greater weight and inertia. To ensure that the stepper motor speed of the energy degrader reaches the set requirements while avoiding the potential danger of rapid acceleration and deceleration, this invention adopts an S-curve approach. Compared with traditional methods, which use a trapezoidal curve for linear acceleration and deceleration, lacking a smooth transition during the ascent or descent, the advantage of the S-curve is that the speed in the middle section (t1 to t2) can be sufficiently high, while the curves on both sides are as smooth as possible. Using the S-curve ensures that the stepper motor reaches the set maximum speed during the constant speed movement phase, while also allowing the motor to smoothly move from the lowest point to the highest point and back to the lowest point, thus solving the problem of sudden starts and stops.

[0031] 3. Solution for the wedge-shaped energy reducer in this invention: Since the energy switching time of the energy reducer is only 50 milliseconds, it is not possible to solve the problem from just one aspect, but rather to save time in every aspect. Each aspect must support and work together to ultimately achieve the 50-millisecond switching time. This invention solves the problem of rapid response from three aspects: communication layer, system layer, and scheduling layer. First, the communication layer uses DDS communication, and the system board and treatment head use DDS communication, saving the time wasted on "handshakes". Second, the system board uses a VxWorks embedded real-time control system, making the switching time of each task shorter and enabling timely feedback from external devices. Third, the system board looks up the corresponding 50-millisecond switching parameters of the motor for the current energy, including motor steps and acceleration, and calls the S-curve to achieve a smooth transition from the lowest to the highest acceleration point, and a smooth transition from the highest to the lowest deceleration point.

[0032] 1. Based on the above principles, this invention designs a control system for a wedge-shaped energy reducer, such as... Figure 1 , 6-1As shown in Figure 6-2, this control system belongs to the proton beam energy selection control system. The wedge de-energizer control system is used to control the wedge de-energizer 1, which is located after the beam outlet of the proton therapy beamline accelerator and passes through a set of quadrupole magnets and guide magnets. The wedge de-energizer control system includes a system board 13, a motion board 12, stepper motor drivers 1-20, stepper motors 1-17, and the wedge de-energizer. The input end of the system board 13 is connected to the treatment head and communicates with the treatment head through DDS, and the output end is connected to the motion board 12. The input end of the stepper motor driver 1-20 is connected to the motion board 12, and the output end is connected to the stepper motor 1-17. The input end of the stepper motor 1-7 is connected to the stepper motor driver 1-20, and the output end is connected to the wedge de-energizer through a cross-slider coupling 1-16.

[0033] The feature is that the energy reduction response time of the paired wedge energy reducer control system is faster than that of the multi-wedge energy reducer, and can complete the energy switching within 50 milliseconds; the paired wedge energy reducer includes a pair of wedge-shaped graphite energy reducing plates 1-1 and 1-2 with tilt angles, the length or distance traveled by the pair of paired wedge energy reducers with tilt angles is several times the length of the multi-wedge energy reducer or the distance traveled by the multi-wedge energy reducing plates, and the width is the same as the sum of the widths of the multi-wedge energy reducing plates.

[0034] Furthermore, the system board is equipped with a VxWorks embedded real-time control system for sending and reading relevant signals.

[0035] Furthermore, the stepper motor driver 1-20 is provided with a motion board interface for an external motion board. The motion information of the relevant stepper motor can be obtained from the motion board 12 through the motion board interface to ensure that the energy switching time is within 50ms each time. The motion information includes the number of steps, motion speed, and motion acceleration that ensure the corresponding time of 50ms.

[0036] Furthermore, the stepper motor driver 1-20 also obtains S-curve parameter information for controlling the stepper motor movement from the motion board 12, including S-curve acceleration parameters, deceleration parameters, and uniform motion parameters. The S-curve parameters are used to control the smooth rise of the stepper motor's acceleration from the lowest point to the highest point, and to control the smooth fall of the stepper motor's deceleration from the highest point to the lowest point.

[0037] Furthermore, such as Figure 1 , Figure 2 , Figure 3 , Figure 4As shown, the system board 13 includes a multi-task scheduling unit and a lookup table unit. The lookup table unit is equipped with an energy degrader lookup table submodule. This submodule performs a lookup table based on the treatment head beam energy value obtained by the system board to obtain the number of steps, movement speed, and movement acceleration of the energy degrader stepper motor that can complete energy switching within 50 milliseconds. The lookup table unit then sends these parameters to the multi-task scheduling unit of the system board. The multi-task scheduling unit sends the number of steps, movement speed, and movement acceleration of the energy degrader to the stepper motor driver 1-20 through the motion board 12.

[0038] Furthermore, such as Figure 4 As shown, the multi-task scheduling unit is provided with an energy degrader task module, which is provided with an initialization task submodule. The initialization task submodule includes calling the S-curve algorithm module, which includes setting the S-curve parameters submodule. The S-curve parameter submodule sets the four acceleration parameters, four deceleration parameters, and uniform motion parameters of the S-curve.

[0039] Furthermore, such as Figure 6-1 As shown, the wedge-shaped energy reducer includes wedge-shaped energy reducers 1-1 and 1-2, an incident collimator 1-3, an exit collimator 1-4, an electronic ruler 1-5, a stepper motor 1-17, a stepper motor driver 1-20, and a support frame 1-19. The wedge-shaped energy reducers 1-1 and 1-2 are vertically mounted on the support frame 1-19 with a certain angle of inclination. The wedge-shaped energy reducers 1-1 and 1-2 are formed by connecting a pair of wedge-shaped graphite energy reducers with an inclination angle through a screw nut and a screw, and a gap is left between the wedge-shaped graphite energy reducers. The beam passes through in a direction perpendicular to the gap. The incident collimator 1-3 and the exit collimator 1-4 are arranged along the beam direction on the wedge-shaped energy reducers. The support frames 1-19 on both sides of the energy reduction plate are at the height of the beamline center point; the electronic ruler 1-5 is arranged on one side of the wedge-shaped energy reduction plate on the support frame, and reads and displays the displacement of the wedge-shaped energy reduction plate as it moves; the stepper motor 1-17 is connected to the wedge-shaped energy reduction plate 1-2 through the cross-slider coupling 1-16 and the right-hand ball screw 1-11, and drives the wedge-shaped energy reduction plate to increase or decrease its thickness; the stepper motor driver 1-20 is connected to the motion board 12 at the input end and to the stepper motor 1-17 at the output end; the universal joint and the lead screw include a right-hand ball screw and a left-hand ball screw, with the universal joint in the middle.

[0040] Furthermore, the pair of wedge-shaped graphite energy reducing plates 1-1 and 1-2 with tilt angles, each wedge-shaped graphite energy reducing plate has a tilt angle of 12°, a thickness of 40 mm, a top corner width of 1 mm, a bottom side width of 100 mm, and a length of 500 mm; the maximum width of the pair of wedge-shaped energy reducing plates during relative movement is 200 mm, and the minimum width is 6 mm.

[0041] Furthermore, the wedge-shaped energy reducing plate includes a right energy reducing plate 1-2 and a left energy reducing plate 1-1; the right energy reducing plate 1-2 is connected to a right-hand screw nut 1-21, which is connected to a right-hand ball screw 1-11; the left energy reducing plate 1-1 is connected to a left-hand screw nut 1-22, which is connected to a left-hand ball screw 1-10. The stepper motor 1-17 is connected to a cross-slider coupling 1-16, which in turn connects to the right-hand ball screw 1-11 for rotation. The right-hand ball screw 1-11 drives the universal joint, which in turn drives the left-hand ball screw 1-10 for rotation. The left-hand ball screw 1-10 drives the left energy reducing plate 1-1 through the left-hand screw nut 1-22, thereby enabling the stepper motor to drive the left energy reducing plate 1-1 and the right energy reducing plate 1-2 to move in opposite directions or away from each other.

[0042] It should be emphasized that the above specific embodiments are merely explanations of the present invention and are not intended to limit the present invention. After reading this specification, those skilled in the art can make modifications to the above embodiments without contributing any inventive step, but as long as they are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A control system for a wedge-shaped energy degrader, the control system belonging to a proton beam energy selection control system. This system, a pair of wedge-shaped de-energizer control system, is used to control the pair of wedge-shaped de-energizers, which are positioned after the beam exit of the proton therapy beamline accelerator and pass through a set of quadrupole magnets and guide magnets. The control system includes a system board, a motion board, a stepper motor driver, a stepper motor, and the pair of wedge-shaped de-energizers. The system board's input end is connected to the treatment head and communicates with it via a DDS, while its output end is connected to the motion board. The stepper motor driver's input end is connected to the motion board, and its output end is connected to the stepper motor. The stepper motor's input end is connected to the stepper motor driver, and its output end is connected to the pair of wedge-shaped de-energizers via a cross-slider coupling. Its features are: The control system for the wedge-shaped energy degrader enables the energy degrader to complete energy switching within 50 milliseconds. The wedge-shaped graphite energy degrader includes a pair of wedge-shaped graphite energy degrading sheets, each with a tilt angle of 12°, a thickness of 40mm, a apex width of 1mm, a bottom side width of 100mm, and a length of 500mm. The system board includes a multi-task scheduling unit, which has an energy degrader task module. This energy degrader task module has an initialization task submodule, which includes an S-curve algorithm module and an S-curve parameter submodule. The system board is equipped with a VxWorks embedded real-time control system for sending and reading relevant signals.

2. The control system for a wedge-shaped energy degrader according to claim 1, characterized in that: The stepper motor driver is equipped with a motion board interface for an external motion board. The motion information of the relevant stepper motor can be obtained from the motion board through the motion board interface to ensure that the energy switching time is within 50ms. This motion information includes the number of steps, motion speed, and motion acceleration that ensure the corresponding time of 50ms.

3. The control system for a wedge-shaped energy degrader according to claim 1, characterized in that: The stepper motor driver also obtains S-curve parameter information for controlling the stepper motor's motion from the motion board, including S-curve acceleration parameters, deceleration parameters, and uniform motion parameters. The S-curve parameters are used to control the stepper motor's acceleration to smoothly rise from the lowest point to the highest point, and to control the stepper motor's deceleration to smoothly fall from the highest point to the lowest point.

4. The control system for a wedge-shaped energy degrader according to claim 1, characterized in that: The system board also includes a lookup unit; the lookup unit has an energy degrader lookup submodule, which performs a lookup based on the treatment head beam energy value obtained by the system board to obtain the number of steps, speed, and acceleration of the energy degrader stepper motor that can complete energy switching within 50 milliseconds. The lookup unit then sends these parameters to the multi-task scheduling unit of the system board, which sends the number of steps, speed, and acceleration of the energy degrader to the stepper motor driver through the motion board.

5. The control system for a wedge-shaped energy degrader according to claim 1, characterized in that: The S-curve parameter submodule allows you to set the four acceleration parameters, four deceleration parameters, and uniform motion parameters of the S-curve.

6. The control system for a wedge-shaped energy degrader according to claim 1, characterized in that: The wedge-shaped energy reducer includes a pair of wedge-shaped energy reducers, an incident collimator, an exit collimator, an electronic ruler, a stepper motor, a stepper motor driver, and a support frame. The wedge-shaped energy reducers are mounted vertically at a certain angle on the support frame. Each pair of wedge-shaped energy reducers consists of a pair of angled wedge-shaped graphite energy reducers connected by a screw and nut, with a gap between them. The beam passes through this gap. The incident and exit collimators are arranged along the beam direction on the support frames on both sides of the wedge-shaped energy reducers. On the frame, its height is the height of the beamline center point; the electronic ruler is installed on one side of the wedge-shaped energy reduction plate on the support frame, and reads and displays the displacement of the wedge-shaped energy reduction plate as it moves; the stepper motor is connected to the wedge-shaped energy reduction plate through a cross-slider coupling and a right-hand ball screw, and drives the wedge-shaped energy reduction plate to increase or decrease its thickness; the stepper motor driver's input end is connected to the motion board, and its output end is connected to the stepper motor; the screw includes a right-hand ball screw and a left-hand ball screw, with a universal joint in the middle.

7. The control system for a wedge-shaped energy degrader according to claim 1, characterized in that: The maximum width of the pair of wedge-shaped energy degraders during relative motion is 200 mm, and the minimum width is 6 mm.

8. The control system for a wedge-shaped energy degrader according to claim 6, characterized in that: The wedge-shaped energy-reducing plates include a right energy-reducing plate and a left energy-reducing plate; the right energy-reducing plate is connected to a right-hand screw nut, which in turn is connected to a right-hand ball screw; the left energy-reducing plate is connected to a left-hand screw nut, which in turn is connected to a left-hand ball screw. The stepper motor is connected to a cross-slider coupling, which in turn connects to the right-hand ball screw for rotation. The right-hand ball screw drives the universal joint, which in turn drives the left-hand ball screw to rotate. The left-hand ball screw, through the left-hand screw nut, drives the left energy-reducing plate to move, thereby enabling the stepper motor to drive the left and right energy-reducing plates to move in opposite directions or away from each other.

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