Linear potentiometer, beam delivery system and related apparatus

Abstract

The application provides a linear potentiometer, a beam distribution system and related equipment, and relates to the technical field of particle radiotherapy, wherein the linear potentiometer comprises: a first conductive layer, a second conductive layer and a resistance layer which are sequentially stacked in the thickness direction; a first insulating layer is arranged between the first conductive layer and the second conductive layer; through structures are arranged on the first insulating layer at intervals; a hollow insulating layer is arranged between the second conductive layer and the resistance layer; one end of the resistance layer is grounded, and the other end is connected with an input voltage; the first insulating layer is arranged, which is beneficial to improving the position measurement accuracy of the potentiometer; meanwhile, the position deviation has a small relationship with the length of the measurement distance, so that the stability of measurement is ensured; the characteristic curve of the signal voltage and displacement obtained by the pressure head sliding is used, so that the measurement and positioning of the pressure head position can be realized through simple calculation.

Description

[0001] This application is a divisional application of Chinese application CN2025102825416, filed on March 11, 2025, entitled "Linear Potentiometer, Beam Delivery System and Related Equipment". Technical Field

[0002] This invention relates to the field of particle radiotherapy technology, and in particular to linear potentiometers, beam delivery systems and related equipment. Background Technology

[0003] Synchrotron accelerators are used to continuously accelerate particles during their cyclotronic motion, while beam delivery systems guide the beam from the accelerator exit to the patient's lesion. In pencil-beam scanning therapy systems, the high-energy particle beam generated by the synchrotron accelerator needs to be precisely guided to the patient's lesion area via the beam delivery system. This system needs to integrate core functions such as range modulation, beam spot positioning, dose monitoring, and target edge trimming. The adaptive grating dynamically adjusts the beam morphology to ensure precise irradiation of the lesion area while maximizing the protection of surrounding healthy tissue, placing extremely high demands on the positioning accuracy of the treatment device.

[0004] During treatment, the positioning phase requires the beam delivery components to retract fully to provide ample space for patient positioning calibration, while the treatment phase necessitates the precise extension of critical components such as the treatment head to the preset positions. This dynamic position switching demands millimeter-level measurement accuracy from the position monitoring system, ensuring both the prevention of collisions between the treatment head and the patient and the accuracy of beam focusing characteristics and dose distribution. To achieve a sharper beam edge, an adaptive grating needs to operate close to the body surface while maintaining sufficient safety clearance; a position sensing system needs to be designed to balance measurement accuracy and equipment reliability over long strokes. Summary of the Invention

[0005] To address the aforementioned issues, this invention provides a linear potentiometer, a beam delivery system, and related equipment to accurately monitor the extension and retraction distance of the stent, ensuring the accuracy of the gap between the treatment head and the patient.

[0006] In a first aspect, the present invention provides a linear potentiometer, comprising:

[0007] A first conductive layer, a first insulating layer, and a resistive layer are sequentially stacked along the thickness direction; the first insulating layer has through structures spaced apart along the thickness direction.

[0008] The characteristic dimension of the through structure in the direction of movement of the sliding pressure head is greater than the distance between two adjacent through structures, and the characteristic dimension is the maximum span distance of the through structure in the direction of movement of the sliding pressure head.

[0009] Preferably, the through structures on the first insulating layer are arranged at equal intervals.

[0010] Preferably, the first insulating layer is made of a flexible insulating material.

[0011] Preferably, the linear potentiometer further includes a second insulating layer and a mounting support layer, wherein the second insulating layer covers the first conductive layer; the resistive layer is located between the hollow insulating layer and the mounting support layer.

[0012] In a second aspect, the present invention provides a position monitoring method, implemented using a linear potentiometer as described in any one of the present invention, the method comprising:

[0013] Starting from the beginning of the potentiometer, the through-structures of the first insulating layer are numbered sequentially, and the position number of each through-structure is associated with the corresponding displacement.

[0014] The sliding indenter slides on the potentiometer, and the full stroke of the potentiometer is calibrated by the sliding indenter to obtain the voltage-displacement characteristic curve;

[0015] Obtain the current signal voltage, and based on the voltage-displacement characteristic curve, obtain the slope of the curve segment where the current voltage is located;

[0016] The current position is obtained based on the current voltage, the slope of the curve in the section where the current voltage is located, and the number of through structures crossed by the sliding pressure head.

[0017] Optionally, multiple calibration voltage points and their corresponding displacements are generated by using the displacement corresponding to each adjacent through-structure interval when the sliding pressure head moves to that position and the voltage at the moment before the sliding pressure head reaches that position, thus obtaining a voltage-displacement characteristic curve; a linear segment is formed between adjacent calibration voltage points.

[0018] Optionally, multiple calibration voltage points and their corresponding displacements are generated by using the displacement corresponding to each through-structure position when the sliding pressure head moves to that position and the voltage at the moment before the sliding pressure head reaches that position, thus obtaining a voltage-displacement characteristic curve; a linear segment is formed between adjacent calibration voltage points.

[0019] Thirdly, the present invention provides a beam delivery system, comprising:

[0020] Telescopic bracket, used to support and adjust the spatial position of scanning magnet, ionization chamber, range adjustment plate and adaptive grating;

[0021] The linear potentiometer described in any of the present invention is used to monitor the displacement of the telescopic bracket when it extends or retracts in real time.

[0022] The control unit is connected to the linear potentiometer signal and is configured to:

[0023] The actual displacement of the telescopic support is calculated based on the linear potentiometer signal.

[0024] By comparing the deviation between the actual displacement and the preset displacement, the position of the telescopic support is adjusted through feedback control until the error is less than the set threshold.

[0025] Preferably, the telescopic bracket is configured as follows:

[0026] The volume is reduced to a minimum during patient placement to free up treatment room space;

[0027] During the treatment phase, the beam extends to a preset position according to the treatment plan to ensure the accuracy of beam delivery.

[0028] Fourthly, the present invention provides a proton radiotherapy device, comprising:

[0029] Accelerators are used to provide proton beams;

[0030] The beam delivery system described in this invention is used to control the shape and position of the beam.

[0031] Fifthly, the electronic device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the steps of any of the methods of the present invention or to implement the functions of the beam delivery system of the present invention.

[0032] In a sixth aspect, the present invention provides a computer-readable storage medium storing computer instructions, wherein when a computer reads the computer instructions, the computer executes the steps of any of the methods described in the present invention or implements the function of a beam delivery system.

[0033] Compared with the prior art, the beneficial effects of the present invention include at least the following: by stacking a first conductive layer, a second conductive layer, and a resistive layer, and setting a first insulating layer and a hollow insulating layer therebetween, precise electrical contact and isolation control can be achieved, ensuring a simple structure while improving the accuracy of position monitoring; by segmenting the non-absolutely linear resistance through structural design, the resistance will maintain a high linearity within the smallest possible segment, and the measured signal includes analog signals within the small segment and segmented pulse signals; the overall accuracy of the linear potentiometer consists of two parts, one part is determined by the machining and manufacturing precision of the distance between adjacent pulse signals, and the other part is determined by the non-uniformity of the resistance distribution within a small distance; the accuracy composed of these two parts will be higher than the overall accuracy of a traditional resistance potentiometer. Setting the interval range and equal spacing of the through-structure on the first insulating layer, and relying on the precision of the through-structure processing, helps to improve the position measurement accuracy of the potentiometer; at the same time, the position deviation is less related to the measurement distance, ensuring the stability of the measurement; by using the characteristic curve of signal voltage and displacement obtained by the sliding of the pressure head, the position of the pressure head can be measured and located through simple calculations (such as calculating the position based on the signal voltage and slope), which significantly improves the measurement accuracy of large stroke distances. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the circuit principle of a common sliding resistor potentiometer according to an embodiment of the present invention;

[0035] Figure 2 This is a schematic diagram of the structure and circuit of a linear potentiometer according to an embodiment of the present invention;

[0036] Figure 3 This is a schematic diagram of another linear potentiometer structure and circuit according to an embodiment of the present invention;

[0037] Figure 4 This is a partial schematic diagram of the linear potentiometer structure according to an embodiment of the present invention;

[0038] Figure 5 This is a schematic diagram of the structure after the second conductive layer and the resistive layer are connected in an embodiment of the present invention;

[0039] Figure 6 This is a schematic diagram of the structure after the first conductive layer and the second conductive layer come into contact according to an embodiment of the present invention;

[0040] Figure 7 This is a schematic diagram of the circuit principle of the linear potentiometer according to an embodiment of the present invention;

[0041] Figure 8 This is a schematic diagram of the location monitoring method according to an embodiment of the present invention;

[0042] Figure 9 This is a schematic diagram of the voltage-displacement characteristic curve of an embodiment of the present invention.

[0043] In the diagram: 1. Second insulating layer; 21. First conductive layer; 22. Second conductive layer; 3. First insulating layer; 4. Resistive layer; 5. Hollow insulating layer; 6. Mounting support layer; 7. Through structure; 8. Sliding pressure head. Detailed Implementation

[0044] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided to make the invention more thorough and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0045] Before introducing this invention, we will first explain the working principle of a common sliding resistance potentiometer, referring to the appendix. Figure 1 Appendix Figure 1 This is a schematic diagram of the circuit principle of a common sliding resistor potentiometer according to an embodiment of the present invention;

[0046] The working principle of a common sliding resistance potentiometer is: resistance R = ρ * L / A, where ρ is the resistivity of the material, L is the total length of the sliding resistance material, and A is the cross-sectional area of ​​the material. Under other constant conditions, the resistance has a linear relationship with the length of the material. Its working circuit is shown in the attached figure. Figure 1 As shown, the relationship between the sliding displacement S (contact length) and the voltage signal is V = U * S / L (U is the voltage across the resistor). Since the cross-sectional area of ​​the material cannot be guaranteed to be absolutely uniform during the manufacturing process, positional errors are caused. The longer the total length L, the greater the positional error will be.

[0047] Example 1, refer to Appendix Figure 2 , attached Figure 2 This is a schematic diagram of a linear potentiometer structure according to an embodiment of the present invention;

[0048] One embodiment of the present invention provides a linear potentiometer, comprising:

[0049] A first conductive layer 21, a first insulating layer 3, and a resistive layer 4 are sequentially stacked along the thickness direction; the insulating grid 3 is provided with multiple through structures 7 at intervals along the thickness direction;

[0050] The through-structure 7 extends from the side where the first insulating layer 3 is adjacent to the first conductive layer 21 to the other side where the first insulating layer 3 is adjacent to the resistive layer 4, and the first conductive layer 21 is connected to the resistive layer 4 through the through-structure 7.

[0051] One end of the resistive layer 4 is grounded (along the length direction), and the other end is connected to the input voltage (along the length direction); one end of the first conductive layer 21 is connected to the input voltage (along the length direction), and the other end outputs a voltage signal.

[0052] The first conductive layer 21 can be made of metal; the resistive layer 4 can be made of, for example, carbon film or metal ceramic; the surface of the resistive layer 4 can be provided with an anti-oxidation coating, the thickness of which can be 50-200 nm and the resistance change rate <0.1%.

[0053] When the sliding pressure head 8 moves to the through structure 7, the first conductive layer 21 contacts the resistive layer 4, and the contact point divides the resistive layer 4 into two segments with a contact length (sliding displacement) of S. At this time, the signal voltage output by the first conductive layer 21 is V. When the sliding pressure head 8 moves to the interval position between two adjacent through structures, the first conductive layer 21 does not contact the resistive layer 4, and the input voltage U is the output voltage V of the first conductive layer 21. By obtaining the signal voltage V output by the first conductive layer 21 at the position, the position of the contact point is calculated, and continuous displacement detection is realized.

[0054] In one possible implementation, the linear potentiometer further includes a second insulating layer 1 and a mounting support layer 6, wherein the second insulating layer 1 is located on the top layer of the stacked structure and covers the first conductive layer 21; and the mounting support layer is located on the bottom layer of the stacked structure.

[0055] The second insulating layer 1 is made of a wear-resistant flexible insulating material, such as ultra-high molecular weight polyethylene film or polyurethane film, and its surface is plasma treated to enhance its adhesion to the first conductive layer 21; the first conductive layer 21 and the first insulating layer 3 can be cured and bonded together by thermosetting adhesive during hot pressing.

[0056] The mounting support layer 6 is also made of insulating material, which provides insulation protection for the resistor layer 4 and serves as the base layer for mounting the potentiometer. It can be adhesive-backed or a fixing plate of a certain thickness. The resistor layer 4 is attached to the mounting support layer 6.

[0057] The second insulating layer 1, the first conductive layer 21, the first insulating layer 3, the resistive layer 4, and the mounting support layer 6 can be integrally formed into a composite laminate structure through hot pressing; alternatively, injection molding can be used, where each layer is pre-embedded in a mold, and molten insulating material (such as polycarbonate) is injected and then cooled to form the final shape. In hot pressing, staged temperature control (e.g., pre-pressing at 80℃, curing at 120℃, and cooling at 60℃) is employed to avoid interlayer bubbles. If a low-viscosity insulating material (such as liquid silicone rubber) is used in injection molding, it ensures thorough penetration and bonding between the layers.

[0058] In some possible implementations, the through structures 7 on the first insulating layer 3 are arranged at equal intervals; the through structures are arranged at equal intervals and numbered at their positions, providing clear reference points for position monitoring; by recording the number of occurrences and position numbers of specific voltage signals, the approximate position range of the sliding pressure head can be quickly determined, and the correspondence between signal voltage and position can be further calculated more accurately, thus improving the accuracy of position monitoring.

[0059] In some possible implementations, the through structure 7 can be a through hole or a through slot that completely penetrates the width direction (i.e., a horizontal direction parallel to the laminated surface); the through hole can be elliptical, circular, or square, wherein the positional accuracy of the through structure can be controlled within ±0.01mm or ±0.02mm; the through structure can be obtained by high-precision die stamping, machining, or other processes, or it can be formed by laser etching or micro-injection molding. These processes can well meet the positional accuracy requirements of the through structure, and also have a certain degree of flexibility and scalability. The size, shape (such as elliptical, circular, or square) and spacing of the through structure can be adjusted according to different application requirements. The positional accuracy of the through structure is within ±0.01mm or ±0.02mm, which makes the error in determining the position of each through structure extremely small, further ensuring the accuracy of position monitoring, and is especially suitable for application scenarios with high positional accuracy requirements.

[0060] In some possible implementations, the characteristic dimension of the through structure 7 in the direction of movement of the sliding pressure head 8 is greater than the distance between two adjacent through structures 7, where the characteristic dimension is the maximum span distance of the through structure 7 in the direction of movement of the sliding pressure head 8; for example, if the through structure 7 is circular, the diameter of the circle is greater than the distance between two adjacent through structures; if the through structure 7 is rectangular, the side length of the rectangle in the direction of movement of the sliding pressure head is greater than the distance between two adjacent through structures 7; if the through structure 7 is elliptical, the diameter of the ellipse in the direction of movement of the sliding pressure head is greater than the distance between two adjacent through structures 7; the distance between two adjacent through structures 7 is as small as possible while meeting the processing capacity requirements.

[0061] In some possible implementations, each through structure 7 has the same size.

[0062] In some possible implementations, the first insulating layer 3 is made of a flexible insulating material; for example, the material of the first insulating layer 3 is preferably an ultra-high molecular weight polyethylene film with a thickness of 0.1-1 mm. The first insulating layer 3 being made of a flexible insulating material (such as an ultra-high molecular weight polyethylene film) allows it to better adapt to the movement and pressure changes of the sliding pressure head. When pressure is applied by the sliding pressure head, the flexible first insulating layer 3 can undergo a certain deformation, ensuring reliable contact between the conductive layer 2 and the resistive layer 4 at the through-structure location, thereby guaranteeing accurate signal acquisition.

[0063] In some possible implementations, the linear potentiometer also includes a temperature sensor located near the resistive layer 4, used to acquire temperature data in real time and correct displacement calculation errors through a compensation algorithm, thereby correcting temperature drift of the voltage-displacement curve.

[0064] In some possible implementations, V bc=V b *(1+α(T-T0)), where α is the temperature coefficient of the resistive film, T0 is the preset temperature, T is the current temperature, and V b For real-time voltage acquisition, V bc To correct the voltage.

[0065] The above technical solution achieves the following effects: coarse positioning is achieved through discrete interval trigger signals (voltage value U), and fine positioning is achieved by linear interpolation of the continuous voltage divider signal (V) of the through structure. This effectively reduces the error caused by the inability to guarantee absolute uniformity of the cross-sectional area of ​​the resistive material and the long total length, thus improving the positioning accuracy. The multi-layer structure (conductive film, insulating layer, resistive film) is integrated into a single piece through hot pressing or injection molding processes, reducing assembly complexity and avoiding the wear problem of mechanical sliding contacts in traditional potentiometers. The voltage-displacement characteristic curve is automatically generated by the full stroke movement of the sliding pressure head, supporting real-time updates of calibration point data and adapting to resistive film aging or temperature drift.

[0066] Example 2, refer to Appendix Figure 3-4 , attached Figure 3 This is a schematic diagram of another linear potentiometer structure according to an embodiment of the present invention;

[0067] An embodiment of the present invention provides a linear potentiometer, comprising: a first conductive layer 21, a first insulating layer 3, and a resistive layer 4 sequentially stacked along the thickness direction; a plurality of through structures 7 are spaced apart on the first insulating layer 3 along the thickness direction;

[0068] The linear potentiometer also includes a second conductive layer 22;

[0069] The first insulating layer 3 is disposed between the first conductive layer 21 and the second conductive layer 22;

[0070] A hollow insulating layer 5 is also provided between the second conductive layer 22 and the resistive layer 4.

[0071] The first conductive layer 21 and the second conductive layer 22 can be made of metal; the resistive layer 4 can be made of, for example, carbon film or metal ceramic.

[0072] The hollow insulation layer 5 can be composed of multiple composite materials, such as a gradient elastic modulus material (e.g., silicone-polyurethane composite layer), with the upper layer being soft to adapt to pressure deformation and the lower layer being rigid to maintain structural stability.

[0073] One end of the resistive layer 4 is grounded (along the length direction), and the other end (along the length direction) is connected to the input voltage; one end of the first conductive layer 21 (along the length direction) is connected to the input voltage; and a voltage signal is output through one end of the second conductive layer 22.

[0074] The surface of the resistive layer 4 can be provided with an anti-oxidation coating, the thickness of which can be 50-200nm, and the resistance change rate is <0.1%.

[0075] See attached document Figure 5 The hollow insulating layer 5 has a certain thickness and is hollow. It has insulating support structures at both ends along its length and a hollow structure in the middle, providing an isolation space between the second conductive layer 22 and the resistive layer 4. This ensures that the second conductive layer 22 and the resistive layer 4 maintain a certain distance when there is no external pressing load, avoiding direct contact. When the sliding pressure head 8 slides in the hollow position of the hollow insulating layer 5, but not at the through structure of the first insulating layer 3, the first conductive layer 21 and the second conductive layer 22 are not in contact. However, the second conductive layer 22 can pass through the hollow area of ​​the hollow insulating layer 5 and contact the resistive layer 4, thereby achieving signal voltage transmission. The contact point divides the resistive layer 4 into two segments with a contact length (sliding displacement) of S. At this time, the signal voltage output by the second conductive layer 22 is V. By acquiring the signal voltage output by the second conductive layer 22 at different contact points, the position of the contact point is calculated, achieving continuous displacement detection.

[0076] See attached document Figure 6 When the sliding head 8 slides on the potentiometer, each time it passes a position of the through-structure 7, since there is no insulating barrier at the through-structure 7, the first conductive layer 21 and the second conductive layer 22 will make electrical contact through the through-structure 7; the signal voltage directly obtains the input voltage U; as the sliding head 8 slides on the potentiometer, each time it moves an interval, the signal voltage obtains a signal with a voltage value of U once. The positional accuracy of the sliding head depends on the manufacturing accuracy of the spacing between the insulating grating holes. By recording the number of times these signals with a voltage value of U appear (corresponding to the number of through-structures) and the corresponding position numbers, the position of the sliding head 8 can be initially located; through the initial positioning of the sliding head 8 and the current signal voltage value, the precise position of the sliding head 8 is obtained. The circuit schematic is shown in Appendix. Figure 7 .

[0077] In some possible implementations, the linear potentiometer also includes a temperature sensor located near the resistive layer 4, used to acquire temperature data in real time and correct displacement calculation errors through a compensation algorithm, thereby correcting temperature drift of the voltage-displacement curve.

[0078] In some possible implementations, V bc =V b *(1+α(T-T0)), where α is the temperature coefficient of the resistive film, T0 is the preset temperature, T is the current temperature, and V b For real-time voltage acquisition, V bc To correct the voltage.

[0079] In one possible implementation, the linear potentiometer further includes a second insulating layer 1 and a mounting support layer 6. The second insulating layer 1 is located at the top in the thickness direction and covers the first conductive layer 21. The resistive layer 4 is located between the hollow insulating layer 5 and the mounting support layer 6. The second insulating layer 1 is made of a wear-resistant flexible insulating material, such as ultra-high molecular weight polyethylene film or polyurethane film, and its surface is plasma treated to enhance adhesion to the first conductive layer 21. The first conductive layer 21 and the first insulating layer 3 can be cured and bonded together by thermosetting adhesive during hot pressing.

[0080] The mounting support layer 6 is also made of insulating material, which provides insulation protection for the resistor layer 4 and the hollow insulating layer 5. It also serves as the base layer for mounting the potentiometer. It can be adhesive-backed or a fixing plate of a certain thickness. The resistor layer 4 is attached to the mounting support layer 6.

[0081] The second insulating layer 1, the first conductive layer 21, the first insulating layer 3, the second conductive layer 22, the hollow insulating layer 5, the resistive layer 4, and the mounting support layer 6 can be integrally molded into a composite laminate structure using a hot pressing process; alternatively, injection molding can be used, where each layer is pre-embedded in a mold, and molten insulating material (such as polycarbonate) is injected and then cooled to form the final shape. In the hot pressing process, staged temperature control (e.g., pre-pressing at 80℃, curing at 120℃, and cooling at 60℃) is employed to avoid interlayer bubbles. If a low-viscosity insulating material (such as liquid silicone rubber) is used in injection molding, it ensures thorough penetration and bonding between the layers.

[0082] In some possible implementations, multiple through structures 7 are set at equal intervals; the through structures 7 are set at equal intervals and numbered at their positions, providing clear reference points for position monitoring; by recording the number of occurrences and position numbers of a specific voltage signal (voltage value U), the approximate position range of the sliding pressure head can be quickly determined, and the correspondence between signal voltage and position can be further calculated more precisely, thus improving the accuracy of position monitoring.

[0083] In some possible implementations, the through structure 7 can be a through hole or a through slot that completely penetrates the width direction (i.e., a horizontal direction parallel to the laminated surface); the through hole can be elliptical, circular, or square, and the through structure can also be elliptical, circular, or square; the chamfer angle of the through structure edge can be 30° to 45°, etc., wherein the positional accuracy of the through structure can be controlled within ±0.01mm or ±0.02mm; the through structure can be obtained by high-precision die stamping, machining, or other processes, or it can be formed by laser etching or micro-injection molding. These processes can well meet the positional accuracy requirements of the through structure, and also have a certain degree of flexibility and scalability. The size, shape (such as elliptical, circular, or square) and spacing of the through structure can be adjusted according to different application requirements. The positional accuracy of the through structure is within ±0.01mm or ±0.02mm, which makes the error in determining the position of each through structure extremely small, further ensuring the accuracy of position monitoring, and is especially suitable for application scenarios with high positional accuracy requirements.

[0084] In some possible implementations, the characteristic dimension of the through structure 7 in the moving direction of the sliding pressure head 8 is smaller than the distance between two adjacent through structures 7, where the characteristic dimension is the maximum span distance of the through structure 7 in the moving direction of the sliding pressure head 8. For example, if the through structure 7 is circular, the diameter of the circle is smaller than the distance between two adjacent through structures 7; if the through structure 7 is rectangular, the side length of the rectangle in the moving direction of the sliding pressure head is smaller than the distance between two adjacent through structures 7; if the through structure 7 is elliptical, the diameter of the ellipse in the moving direction of the sliding pressure head is smaller than the distance between two adjacent through structures 7. The characteristic dimension of the through structure 7 in the moving direction of the sliding pressure head 8 is as small as possible while satisfying the requirements of processing capacity and ensuring that the first conductive layer 21 and the second conductive layer 22 can make contact.

[0085] In some possible implementations, the spacing between adjacent through-structures on the first insulating layer 3 is greater than or equal to 10 mm and less than or equal to a first threshold, where the first threshold can be 30 mm or 60 mm, determined according to the required control precision. The 10 mm or greater spacing takes into account machining capabilities. In common machining methods, such as drilling and milling, the size and precision of the cutting tools are limited. If the spacing between two adjacent through-structures is too small, the cutting tools are prone to interference during machining, leading to decreased machining accuracy and potentially damaging the cutting tools and workpiece. Generally, conventional machining equipment struggles to guarantee the dimensional and positional accuracy of holes when machining through-structures with a spacing less than 10 mm, easily resulting in problems such as hole diameter deviation and uneven hole spacing, thus affecting the quality and performance of the first insulating layer 3. Simultaneously, when the spacing between two adjacent through-structures 9 is too small, the material is more susceptible to these defects under machining stress, thereby reducing the reliability of the first insulating layer. Setting the spacing to greater than or equal to 10 mm can alleviate the impact of machining stress on the material to some extent and improve the machining success rate.

[0086] In some possible implementations, the first insulating layer 3 is made of a flexible insulating material; for example, the material of the first insulating layer 3 is preferably an ultra-high molecular weight polyethylene film with a thickness of 0.1-1 mm; the first insulating layer 3 is made of a flexible insulating material (such as an ultra-high molecular weight polyethylene film), which allows the first insulating layer 3 to better adapt to the movement and pressure changes of the sliding pressure head. When the sliding pressure head applies pressure, the flexible first insulating layer 3 can undergo a certain deformation, ensuring that the first conductive layer 21 and the second conductive layer 22 can reliably contact at the position of the through structure 7, thereby ensuring accurate signal acquisition.

[0087] The above technical solution achieves the following effects: coarse positioning (accuracy depends on the spacing of the through-structures) is achieved by using discrete through-structure trigger signals (voltage value U), and fine positioning is achieved by combining linear interpolation of continuous voltage divider signals (V). This effectively reduces errors caused by the inability to guarantee absolute uniformity of the cross-sectional area of ​​the resistive material and the long total length, thus improving positioning accuracy. By integrating multi-layer structures (conductive film, insulating layer, resistive film) into a single piece through hot pressing or injection molding processes, assembly complexity is reduced, and the wear problem of mechanical sliding contacts in traditional potentiometers is avoided. The voltage-displacement characteristic curve is automatically generated by the full stroke movement of the sliding pressure head, supporting real-time updates of calibration point data and adapting to resistive film aging or temperature drift.

[0088] Example 3 provides a position monitoring method, implemented using the linear potentiometer described in Example 1 or 2 of this application. The method includes:

[0089] Starting from the beginning of the potentiometer, the through-structures of the first insulating layer are numbered sequentially, and the position number of each through-structure is associated with the corresponding displacement.

[0090] The sliding indenter slides on the potentiometer, and the full stroke of the potentiometer is calibrated by the sliding indenter to obtain the voltage-displacement characteristic curve;

[0091] Obtain the current signal voltage, and based on the number of times the U signal is triggered and the voltage-displacement characteristic curve, obtain the slope of the current voltage segment.

[0092] The current position is obtained based on the current voltage, the slope of the curve containing the current voltage, and the number of through structures crossed by the sliding pressure head.

[0093] In one possible implementation, multiple calibration voltage points and their corresponding displacements are generated by using the displacement corresponding to the sliding pressure head when it moves to the position of each adjacent through-structure interval and the voltage at the moment before the sliding pressure head reaches that position, thus obtaining a voltage-displacement characteristic curve; a linear segment is formed between adjacent calibration voltage points.

[0094] In another possible implementation, multiple calibration voltage points and their corresponding displacements are generated by using the displacement corresponding to each through-structure position when the sliding pressure head moves to that position and the voltage at the moment before the sliding pressure head reaches that position, thus obtaining a voltage-displacement characteristic curve; a linear segment is formed between adjacent calibration voltage points.

[0095] The working principle of the above technical solution is as follows:

[0096] See attached document Figure 8 Starting from the beginning of the potentiometer, each through structure of the first insulating layer 3 is sequentially numbered as position number i = 0, 1, 2, 3...M. The position number of the first through structure is set to 0, and the position numbers of each subsequent through structure are sequentially increased, such as 1, 2, 3...M. The position number i of each through structure is associated with the displacement (Si) of the corresponding sliding pressure head 8, thus providing a basis for determining the position of the sliding pressure head 8.

[0097] Regarding the structure of Example 1,

[0098] By measuring the displacement of the sliding pressure head when it moves to the position of each adjacent through-structure interval and the voltage at the moment before the sliding pressure head reaches that position, multiple calibration voltage points and their corresponding displacements are generated, thus obtaining a voltage-displacement characteristic curve; a linear region is formed between adjacent calibration voltage points.

[0099] When the sliding indenter slides on the linear potentiometer, each time it passes through the interval between two adjacent through-structures, the first conductive layer and the resistive layer are not in contact, and the signal voltage directly obtains the input voltage U; as the sliding indenter slides on the potentiometer, each time it moves one interval, the signal voltage obtains a signal with a voltage value of U once. The positional accuracy of the movement is determined by the manufacturing accuracy of the through-structure. By recording the number of times these signals with a voltage value of U appear and their corresponding position numbers, the position of the sliding indenter can be initially located.

[0100] When the sliding pressure head passes through the gap between two adjacent through-structures of the first insulating layer, a signal voltage with a value of U is acquired. The displacement (Si) corresponding to this voltage signal is recorded, and the voltage at the moment before the change to the voltage value U is taken as the voltage (V) corresponding to this displacement (Si). i By calibrating the potentiometer across its entire stroke using a sliding indenter, a voltage-displacement characteristic curve is obtained. This characteristic curve is generated from discrete calibration voltage points (V...). i It consists of the voltage and its corresponding position displacement (Si), forming a linear segment between adjacent calibration voltage points;

[0101] During the movement of the sliding pressure head, the current signal voltage V is obtained from the signal terminal through the first conductive layer. b Then, first find the voltage-displacement characteristic curve that corresponds to V. b The two closest known voltage values ​​are used to determine the relationship with V in the voltage-displacement characteristic curve. b Two adjacent calibration voltage points (V) i V i+1 ), to obtain the slope K of this section. i =(V i+1 -V i ) / (S i+1 -S i );

[0102] The current position is obtained based on the current voltage, the slope of the curve in the segment where the current voltage is located, and the number of through structures crossed.

[0103] The current position is obtained based on the current voltage, the slope of the curve in the segment where the current voltage is located, and the number of through structures crossed. Specifically, this includes:

[0104] Let the position of V1 be 0, V b The corresponding position is S b =S i +(V b -V i ) / K i ;

[0105] If all through-structures have the same dimensions (i.e., fixed displacement), then Si = J*(i+1), for example, V b Between V8 and V9, i = 8. If the characteristic dimension of the through structure is 20mm, S8 = 20 * 9 = 180mm; J is the characteristic dimension of the through structure.

[0106] If the dimensions of the through structure are different, then S i =J0+J1+...+J i For example, if Vb is between V8 and V9, then i = 8.

[0107] For the structure of Embodiment 2, please refer to the appendix. Figure 5 Appendix Figure 6 and attached Figure 9 :

[0108] By measuring the displacement of the sliding pressure head when it moves to the position of each adjacent through-structure interval and the voltage at the moment before the sliding pressure head reaches that position, multiple calibration voltage points and their corresponding displacements are generated, thus obtaining a voltage-displacement characteristic curve; a linear segment is formed between adjacent calibration voltage points.

[0109] When the sliding pressure head slides on the potentiometer, each time it passes through a through-structure position, since there is no insulating barrier at the through-structure, the first conductive layer and the second conductive layer will make electrical contact through the through-structure; the signal voltage directly obtains the input voltage U; as the pressure head slides on the potentiometer, each time it moves an interval, the signal voltage obtains a signal with a voltage value of U once. The positional accuracy of the movement depends on the manufacturing accuracy of the spacing between the insulating grating holes. By recording the number of times these signals with a voltage value of U appear and their corresponding position numbers, the position of the sliding pressure head can be initially located.

[0110] When the sliding pressure head passes through a certain through-structure position of the first insulating layer, the first conductive layer and the second conductive layer come into contact. At this time, a signal voltage with a voltage value of U is acquired. The displacement (Si) corresponding to this voltage signal is recorded, and the voltage at the moment before the recorded voltage value of U is taken as the voltage (V) corresponding to this displacement (Si). i By calibrating the potentiometer across its entire stroke using a sliding indenter, a voltage-displacement characteristic curve is obtained. This characteristic curve is generated from discrete calibration voltage points (V...). i It consists of the voltage and its corresponding position displacement (Si), forming a linear segment between adjacent calibration voltage points;

[0111] During the movement of the sliding pressure head, the current signal voltage V is obtained through the signal terminal of the second conductive layer. b Then, first find the voltage-displacement characteristic curve that corresponds to V. b The two closest known voltage values ​​are used to determine the relationship with V in the voltage-displacement characteristic curve. bTwo adjacent calibration voltage points (V) i V i+1 ), to obtain the slope K of this section. i =(V i+1 -V i ) / (S i+1 -S i );

[0112] The current position is obtained based on the current voltage, the slope of the curve in the segment where the current voltage is located, and the number of through structures crossed.

[0113] The current position is obtained based on the current voltage, the slope of the curve in the segment where the current voltage is located, and the number of through structures crossed. Specifically, this includes:

[0114] Let the position of V1 be 0, V b The corresponding position is S b =S i +(V b -V i ) / K i ;

[0115] If adjacent through structures are set at equal intervals (i.e., with a fixed displacement), then S i =D*i, for example, V b Between V8 and V9, i = 8, the interval between adjacent through structures is 20mm, S8 = 20 * 8 = 160mm; D is the interval between adjacent through structures;

[0116] If adjacent through structures are not equally spaced, S i =D1+D2+...+D i For example, if Vb is between V8 and V9, then i = 8, D1 is the interval between the first and second through structures, D2 is the interval between the second and third through structures, D8 is the interval between the ninth and eighth through structures, and S8 = D1 + D2 + ... + D8.

[0117] In one possible implementation, temperature data is acquired in real time to correct temperature drift in the voltage-displacement curve.

[0118] In one possible implementation, V bc =V b *(1+α(T-T0)), where α is the temperature coefficient of the resistive film, T0 is the preset temperature, T is the current temperature, and V b For real-time voltage acquisition, V bc To correct the voltage.

[0119] In one possible implementation, when an abnormal voltage signal is detected (such as exceeding a preset threshold) or a significant change in environmental parameters (temperature, humidity), the calibration process of the voltage-displacement characteristic curve is automatically triggered.

[0120] And / or,

[0121] Automatically perform full-stroke calibration at preset time intervals (e.g., every 24 hours) or usage counts (e.g., every 10,000 slides), and update the calibration voltage point; for example, if the temperature sensor detects an ambient temperature change exceeding ±5℃, or the voltage at any position exceeds a preset threshold, then calibration is initiated.

[0122] The above technical solution achieves the following effect: It sequentially numbers the through-structures of the first insulating layer from the starting end of the potentiometer, and associates the position numbers with the displacement, providing a clear and orderly basic framework for the initial positioning of the sliding pressure head. This makes subsequent operations to locate the sliding pressure head by recording the number of times the signal with voltage value U appears and the corresponding position number more accurate and convenient. By acquiring the voltage-displacement characteristic curve, combined with the current signal voltage, the slope of the curve in the current segment, and the number of through-structures crossed, the current position is determined. Regardless of whether the through-structures are equally spaced or not, the pressure head position can be accurately calculated according to the corresponding formula. This position determination consists of two parts: the first part is determined by the number of times the signal with voltage value U appears and the displacement corresponding to that number; the error in this part is mainly determined by the manufacturing precision of the insulating grid holes, which can be very precise, for example, within ±0.01mm. The second part, the position value, is calculated from the voltage division of the resistor; since the precision of the voltage division depends on the uniformity of the resistor film cross-section, the precision in this part is guaranteed by the cross-sectional uniformity. However, because this distance is very small, the relationship between the position deviation and the length of the measurement distance is small, thus effectively improving the accuracy of position monitoring.

[0123] By moving the sliding pressure head to the displacement corresponding to each through-structure position and the voltage at the moment before reaching that displacement, a voltage-displacement characteristic curve is generated, consisting of discrete calibration voltage points and their corresponding displacements, and a linear segment is formed between adjacent calibration voltage points. This linear segment characteristic allows the calculation of the current position to be based solely on a simple slope formula, greatly simplifying the calculation process and improving calculation efficiency.

[0124] The system acquires temperature data in real time and corrects for temperature drift in the voltage-displacement curve, taking into account the influence of the resistive film temperature coefficient on the voltage. A correction formula is used to convert the real-time acquired voltage into a corrected voltage, effectively reducing the impact of temperature changes on position monitoring accuracy and ensuring the accuracy and stability of position monitoring under different temperature environments. When an abnormal voltage signal is detected (such as exceeding a preset threshold) or a significant change in environmental parameters (temperature, humidity), the voltage-displacement characteristic curve calibration process is automatically triggered. Simultaneously, full-stroke calibration is automatically performed and the calibration voltage point is updated at preset time intervals (such as every 24 hours) or usage cycles (such as every 10,000 slides). This automatic calibration mechanism can promptly respond to various abnormal situations that may affect the accuracy of position monitoring, ensuring the reliability and stability of the potentiometer during long-term use, reducing the need for manual intervention, and improving the system's intelligence.

[0125] Example 3: This example provides a beam delivery system, including:

[0126] A telescopic support is used to support and adjust the spatial position of the scanning magnet, ionization chamber, range adjustment plate, and adaptive grating; the telescopic support is configured as follows:

[0127] The volume is reduced to a minimum during patient placement to free up treatment room space;

[0128] During the treatment phase, the beam extends to a preset position according to the treatment plan to ensure the accuracy of beam delivery;

[0129] A linear potentiometer is installed at the telescopic shaft or joint of the telescopic bracket to monitor the displacement of the telescopic bracket when it extends or retracts in real time, and outputs an electrical signal that is linearly related to the displacement.

[0130] The control unit, connected to the linear potentiometer signal, is configured to:

[0131] The actual displacement of the telescopic support is calculated based on the linear potentiometer signal.

[0132] By comparing the deviation between the actual displacement and the preset displacement, the position of the telescopic bracket is adjusted through feedback control until the error is less than the set threshold (e.g., ±0.5mm); control strategies include PID control logic or fuzzy control strategy.

[0133] The beam delivery system has the following functions: range modulation, beam spot position control, beam monitoring, target edge trimming, etc.; it is equipped with a variety of advanced optical elements; for example, by using specially designed magnetic lenses and collimators, the lateral and longitudinal dimensions of the proton beam can be adjusted to form a beam profile suitable for the shape of the tumor. The intensity distribution of the beam can also be adjusted by using modulators to achieve differentiated irradiation doses to different parts of the tumor and better adapt to the irregular shape of the tumor.

[0134] In some possible implementations, the linear potentiometer also includes a temperature sensor located near the resistive layer 6 for real-time acquisition of temperature data to correct temperature drift in the voltage-displacement curve; the control unit adjusts the output displacement based on the temperature signal.

[0135] In some possible implementations, V bc =V b *(1+α(T-T0)), where α is the temperature coefficient of the resistive film, T0 is the preset temperature, T is the current temperature, and V b For real-time voltage acquisition, V bc To correct the voltage.

[0136] In some possible implementations, the beam delivery system also includes host computer software for real-time display of displacement, voltage signal waveforms and alarm information, and supports data export and report generation.

[0137] This invention also provides a proton radiotherapy device, comprising:

[0138] An accelerator is used to provide a proton beam; the accelerator can be a synchrotron accelerator.

[0139] The beam delivery system described in this embodiment of the invention is used to control the shape and position of the beam.

[0140] In addition to the accelerator and beam delivery system, the proton therapy device also includes a treatment head, which serves as the final output of the proton beam and acts on the patient.

[0141] In some embodiments, the beam delivery system may be part of the treatment head.

[0142] This invention also provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the method described in this application embodiment or the beam delivery function as described in this application embodiment.

[0143] This application also provides a computer-readable storage medium for storing a computer program. When the computer program is executed, it implements the steps of the method in this application embodiment or the beam delivery function as described in this application embodiment. Its specific implementation is consistent with the implementation methods and technical effects achieved in the above method embodiments, and some contents will not be repeated.

[0144] In this application, a readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. The program product can take the form of any combination of one or more readable media. A readable medium can be a readable signal medium or a readable storage medium. A readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: an electrical connection having one or more wires, a portable disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0145] Computer-readable storage media may include data signals propagated in baseband or as part of a carrier wave, carrying readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. The readable storage medium may also be any readable medium capable of sending, propagating, or transmitting a program for use by or in conjunction with an instruction execution system, apparatus, or device. The program code contained on the readable storage medium may be transmitted using any suitable medium, including but not limited to wireless, wired, optical fiber, RF, or any suitable combination thereof. Program code for performing operations of the present invention may be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar programming languages. The program code may be executed entirely on a user computing device, partially on an associated device, as a standalone software package, partially on a user computing device and partially on a remote computing device, or entirely on a remote computing device or server. In cases involving remote computing devices, the remote computing devices can be connected to user computing devices via any type of network, including local area networks (LANs) or wide area networks (WANs), or they can be connected to external computing devices (e.g., via the Internet using an Internet service provider).

[0146] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the invention without departing from the principles and spirit of the invention, and all such changes should fall within the protection scope of the claims of the present invention.

Claims

1. A linear potentiometer, characterized in that, include: A first conductive layer (21), a first insulating layer (3), and a resistive layer (4) are sequentially stacked along the thickness direction. The first insulating layer (3) is provided with through structures (7) at intervals along the thickness direction. The characteristic dimension of the through structure (7) in the direction of movement of the sliding pressure head is greater than the distance between two adjacent through structures (7), and the characteristic dimension is the maximum span distance of the through structure (7) in the direction of movement of the sliding pressure head; Furthermore, the linear potentiometer is configured to perform position monitoring via the following method: Starting from the beginning of the potentiometer, the through-structures of the first insulating layer are numbered sequentially, and the position number of each through-structure is associated with the corresponding displacement. The sliding indenter slides on the potentiometer, and the full stroke of the potentiometer is calibrated by the sliding indenter to obtain the voltage-displacement characteristic curve; Obtain the current signal voltage, and based on the voltage-displacement characteristic curve, obtain the slope of the curve segment where the current voltage is located; The current position is obtained based on the current voltage, the slope of the curve in the section where the current voltage is located, and the number of through structures crossed by the sliding pressure head.

2. The linear potentiometer according to claim 1, characterized in that, The through structure (7) is set at equal intervals.

3. The linear potentiometer according to claim 1, characterized in that, The first insulating layer (3) is made of a flexible insulating material.

4. The linear potentiometer according to claim 1, characterized in that, The linear potentiometer further includes a second insulating layer (1) and a mounting support layer (6), the second insulating layer (1) covering the first conductive layer (21), and the mounting support layer (6) located at the bottom layer of the stacked structure.

5. A location monitoring method, characterized in that, Monitoring is performed using any of the linear potentiometers described in claims 1-4.

6. The location monitoring method according to claim 5, characterized in that, By measuring the displacement of the sliding pressure head when it moves to the position of each adjacent through-structure interval and the voltage at the moment before the sliding pressure head reaches that position, multiple calibration voltage points and their corresponding displacements are generated, thus obtaining a voltage-displacement characteristic curve; a linear segment is formed between adjacent calibration voltage points.

7. The location monitoring method according to claim 5, characterized in that, By using the displacement corresponding to each through-structure position when the sliding pressure head moves to that position and the voltage at the moment before the sliding pressure head reaches that position, multiple calibration voltage points and their corresponding displacements are generated, and a voltage-displacement characteristic curve is obtained; a linear segment is formed between adjacent calibration voltage points.

8. A beam delivery system, characterized in that, include: Telescopic brackets are used to support and adjust the spatial position of the ionization chamber, range adjustment plate, and adaptive grating; The linear potentiometer according to any one of claims 1-4 is used to monitor the displacement of the telescopic bracket during extension or retraction in real time; The control unit is connected to the linear potentiometer signal and is configured to: The actual displacement of the telescopic support is calculated based on the linear potentiometer signal. By comparing the deviation between the actual displacement and the preset displacement, the position of the telescopic support is adjusted through feedback control until the error is less than the set threshold.

9. The beam delivery system according to claim 8, characterized in that, The telescopic support is configured as follows: The volume is reduced to a minimum during patient placement to free up treatment room space; During the treatment phase, the beam extends to a preset position according to the treatment plan to ensure the accuracy of beam delivery.

10. A proton radiotherapy device, characterized in that, include: Accelerators are used to provide proton beams; The beam delivery system of claim 8 is used to control the shape and position of the beam.

11. An electronic device, characterized in that, The electronic device includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the method according to any one of claims 5-7 or to implement the function of the system according to any one of claims 8-9.

12. A computer-readable storage medium, characterized in that, The storage medium stores computer instructions, and when the computer reads the computer instructions, the computer executes the steps of the method as described in any one of claims 5-7 or implements the functions of the system as described in any one of claims 8-9.

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