Needle set module, puncture actuator and surgical robot

Abstract

The application discloses a needle tube group module, a puncture executor and a surgical robot, and is suitable for retinal blood vessel injection and subretinal layer injection in fundus microsurgery. The needle tube group module comprises a needle tip, an inner tube connected with the needle tip and provided with a curved section at the connection, the inner tube is made of shape memory material and provided with a pre-bending angle, the needle tip and the inner tube are provided with a medicine injection channel, an outer tube, at least part of the inner tube is slidingly connected in the outer tube, the needle tip and the inner tube can do extension and contraction movement in the outer tube, the needle tip, the inner tube and the outer tube can do rotation movement, and a force sensing element is installed on the outer tube. The application solves the problem of adjusting the angle of puncturing the retina, can simultaneously integrate a high-precision intraocular flexible arm and a force sensing element, can accurately sense the depth through the force sensing element in the puncture process of the subretinal layer injection surgery, can prolong the puncture path, avoid drug reflux, and thus improve the success rate of the surgery.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, specifically to needle assembly modules, puncture actuators, and surgical robots. Background Technology

[0002] Subretinal injection (SI) is a minimally invasive treatment that involves directly injecting drugs, gene vectors, or stem cells into the space between the retina and the retinal pigment epithelium (RPE). This area, known as the subretinal space, is a key site of lesions in many retinal diseases.

[0003] The retina is a highly layered neural tissue located at the back of the eyeball. From the outside in, it mainly includes the retinal pigment epithelium (RPE), photoreceptor layer, bipolar cell layer, and ganglion cell layer. The potential space between the RPE layer and the outer segment of the photoreceptor is the target area for subretinal injection. This structure is crucial for the metabolic support of the photoreceptors and the maintenance of visual function; damage to it can lead to irreversible vision loss.

[0004] The injection procedure is typically performed around the fovea of ​​the macula, the area with the highest visual acuity. The surgeon, through the vitreous cavity, selects the puncture point under microsurgical manipulation, uses a microneedle to penetrate the neuroretina, and slowly injects fluid to create a localized retinal bleb, precisely delivering the therapeutic substance into the subretinal space. This process requires strict control of the puncture depth and injection rate to prevent retinal tears or tissue damage.

[0005] Subretinal injection is widely used in the treatment and research of the following diseases: hereditary retinal diseases (such as Leber congenital amaurosis and retinitis pigmentosa): injecting gene therapy vectors (such as AAV vectors); age-related macular degeneration (AMD): delivering anti-angiogenic drugs or stem cells to promote visual function repair; diabetic retinopathy: achieving local delivery of targeted drugs and reducing systemic side effects; experimental animal studies: used for disease model establishment or validation of new therapies.

[0006] Existing retinal injectors, such as the retinal vascular injection device and its injection method for ophthalmic surgical robots disclosed in Chinese patent document CN110368184A (published earlier by the inventor), utilize a needle assembly module to control the horizontal release of the needle tip, a feeding module to feed the needle tip, and a rotation module to rotate the needle tip. They can also move the needle tip vertically under the guidance of the robotic arm of the ophthalmic surgical robot, improving the efficiency of retinal vessel positioning by more than 30% and making vessel positioning more precise. However, during the insertion of the retinal vessel, the bending of the needle tip is pre-bent over a short area, and the needle tip extension length corresponds one-to-one with the angle, limiting the precise adjustment of the bending angle.

[0007] Furthermore, retinal vascular injection differs from subretinal injection. Before subretinal injection, intraocular instruments need to be inserted into the vitreous cavity through a scleral cannula of at least 23G (0.52mm inner diameter). The intraocular instruments then move further, gradually approaching the retina for the surgical procedure. Due to the limitations of the scleral micro-incision size, intraocular instruments cannot simultaneously integrate a flexible intraocular arm and a force-sensing element. This results in subretinal injection lacking tactile sensing and requiring puncture at a fixed, near-vertical angle, which easily leads to over-puncture and reflux during drug injection.

[0008] In summary, existing retinal vascular injection devices cannot simultaneously integrate a high-precision intraocular flexible arm and a force sensing element. This makes it impossible to sense the depth during subretinal injection surgery, thus preventing the extension of the puncture path, leading to drug reflux and reducing the success rate of the surgery. Summary of the Invention

[0009] The purpose of this invention is to provide a needle assembly module, puncture actuator, and surgical robot suitable for retinal vascular injection and subretinal injection in fundus microsurgery, in order to solve the problem that existing retinal vascular injection devices cannot simultaneously integrate a high-precision intraocular flexible arm and force sensing element, which makes it impossible to sense depth and extend the puncture path during subretinal injection surgery, leading to drug reflux and reduced surgical success rate.

[0010] In a first aspect, the present invention provides a needle assembly module, the needle assembly module comprising:

[0011] needle tip;

[0012] The inner tube is connected to the needle tip and is set as a curved section at the connection. The inner tube is made of shape memory material and is set with a pre-bending angle. The needle tip and the inside of the inner tube are provided with drug injection channels.

[0013] The outer tube, at least part of the inner tube, is slidably connected to the outer tube. The needle tip and the inner tube are capable of telescopic movement within the outer tube, and the needle tip, the inner tube, and the outer tube are capable of rotational movement.

[0014] A force sensing element is installed on the outer tube.

[0015] In one embodiment of the present invention, the needle tip and the inner tube are an integral structure, the needle tip is provided with a sharp tip, and the needle tip is made of shape memory material.

[0016] In one embodiment of the present invention, a drug injection tube is further included, which is connected to the inner tube and communicates with the drug injection channel.

[0017] In one embodiment of the present invention, a plurality of force sensing elements are fixed in a ring array to the outer wall of the outer tube near the tip of the needle.

[0018] In one embodiment of the present invention, the force sensing element is a Bragg fiber grating sensor.

[0019] In a second aspect, the present invention provides a puncture actuator, including the aforementioned needle assembly module, and further comprising:

[0020] An inner tube feed module, connected to the inner tube, is used to drive the inner tube and the needle tip to perform telescopic movements within the outer tube;

[0021] A rotating module, connected to the inner tube feeding module, is used to drive the inner tube feeding module and the needle tube assembly module connected to the inner tube feeding module to rotate, so that the needle tip, the inner tube and the outer tube rotate.

[0022] In one embodiment of the present invention, the needle assembly module further includes a mounting bracket, which is mounted on the rotating module. The rotating module is used to drive the mounting bracket to rotate, and the outer tube is inserted into the mounting bracket.

[0023] In one embodiment of the present invention, the inner tube feeding module includes a power drive unit, a lead screw, a lead screw nut, an inner tube connector, and a slide rail. The slide rail is mounted on the mounting frame. One end of the lead screw is rotatably mounted on the mounting frame, and the other end is connected to the power drive unit mounted on the mounting frame. The lead screw nut is mounted on the lead screw, and the slide rail is arranged parallel to the lead screw. The inner tube connector is slidably mounted on the slide rail and connected to the lead screw nut. The inner tube connector is connected to the inner tube, and the inner tube connector moves linearly along the slide rail under the drive of the lead screw nut to drive the inner tube to perform telescopic movement within the outer tube. The power drive unit includes a first drive mechanism, a first pulley driven by the first drive mechanism, and a second pulley connected to the first pulley via a conveyor belt. The second pulley is connected to the lead screw.

[0024] In one embodiment of the present invention, the rotating module includes a second driving mechanism, which is mounted on an actuator mounting base. The output shaft of the second driving mechanism is fitted with a rotating fastening nut, which is connected to the mounting bracket. The second driving mechanism drives the mounting bracket to rotate via the rotating fastening nut.

[0025] Thirdly, the present invention provides a surgical robot, including the aforementioned puncture actuator, and further including a linear guide module, wherein the puncture actuator is mounted on the linear guide module, and the linear guide module is used to drive the puncture actuator to move.

[0026] The beneficial effects of this invention are:

[0027] This invention enables direct injection of medication into the subretinal layer of tiny lesions, successfully overcoming the physiological limitations of the human hand to achieve therapeutic goals. The needle assembly module utilizes a concentric tube structure for flexible adjustment of the puncture angle, ensuring both the precision and stability of the puncture trajectory during insertion and the overall structural stability. Furthermore, the needle tip and inner tube are integrated into a single structure, allowing them to rotate simultaneously at the same angle, thus adjusting the direction of insertion into the blood vessel. Additionally, the needle tip and inner tube within the outer tube have a pre-set, constant curvature. Based on the concentric tube principle, as the needle tip and inner tube extend, the portion protruding from the outer tube gradually changes from a straight line to a curved state, similar to a flexible arm. This ensures precise adjustment of the bending angle of the needle assembly module, and force sensing elements enable accurate retinal puncture injection.

[0028] When not in use, the needle tip of the needle assembly module of this invention can retract into the outer tube along with the inner tube, reducing the overall diameter to less than 0.52 mm, thus facilitating the passage of a 23G scleral cannula. This not only ensures the hygiene of the needle tip but also protects it from external force, preventing changes in the needle tip's curvature that could lead to complications during surgery. Furthermore, it protects the needle tip before it enters the eye. Therefore, this needle assembly module solves the size problem of intraocular instruments integrating force sensing elements and concentric tube-based flexible arms, enabling them to enter the eye through a medical 23G scleral cannula.

[0029] The needle tip and inner tube of this invention are designed as an integrated unit, effectively ensuring the reliability of the connection between them without relying on welding or bonding. Furthermore, this integrated processing method for the needle tip and inner tube can also be applied to straight, rigid needles, allowing the portion entering the eye to have varying thicknesses, thus ensuring overall rigidity. This needle module integrates the needle with a flexible intraocular arm based on the concentric tube principle, solving the reliability problems associated with welding or gluing connections between the needle and the concentric tube.

[0030] This invention integrates a force-sensing element, namely a Bragg fiber grating sensor, with an overall diameter of less than 0.5 mm. It can be inserted into the eye using a 23G medical scleral cannula, ensuring the reliability of the integrated needle tip, and is especially suitable for subretinal injection.

[0031] In summary, this invention solves the problem of adjusting the angle of retinal puncture and can simultaneously integrate a high-precision intraocular flexible arm and a force sensing element. This allows the force sensing element to accurately sense the depth during subretinal injection surgery, extending the puncture path, avoiding drug reflux, and thus improving the success rate of the surgery. Attached Figure Description

[0032] Figure 1 This is a perspective view of the puncture actuator provided by the present invention.

[0033] Figure 2 This is a front view of the puncture actuator provided by the present invention.

[0034] Figure 3 This is a side view of the puncture actuator provided by the present invention.

[0035] Figure 4 This is a top view of the puncture actuator provided by the present invention.

[0036] Figure 5 This is a partial effect diagram of the invention, which controls the pre-bending angle of the inner tube by extending the needle tip.

[0037] Figure 6 This is a rendering of the puncture actuator provided by the present invention installed on a surgical robot.

[0038] Figure 7 This is a schematic diagram of the structure of the present invention when the needle tip and inner tube do not extend out of the outer tube.

[0039] Figure 8 This is a schematic diagram of the process by which the needle tip and inner tube extend out of the outer tube according to the present invention.

[0040] Figure 9 This is a schematic diagram of the needle tip and inner tube rotating inside the outer tube according to the present invention.

[0041] Figure 10 This is a schematic diagram of the overall structure of the outer tube and force sensing element of the present invention.

[0042] Figure 11 yes Figure 10 Sectional view along AA.

[0043] In the diagram: 1. Needle assembly module; 1-1. Needle tip; 1-2. Inner tube; 1-3. Outer tube; 1-4. Force sensing element; 1-5. Injection micro-tube; 1-6. Mounting bracket; 2. Inner tube feeding module; 2-1. First drive mechanism; 2-2. First pulley; 2-3. Conveyor belt; 2-4. Second pulley; 2-5. Lead screw; 2-6. Lead screw nut; 2-7. Inner tube connector; 2-8. Slide rail; 2-9. Tensioner; 3. Rotation module; 3-1. Bearing; 3-2. Rotary fastening nut; 3-3. Second drive mechanism; 4. Actuator mounting base; 5. Linear guide module; 5-1. Sliding platform; 5-2. Linear guide; 5-3. Third drive mechanism. Detailed Implementation

[0044] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions.

[0046] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and connections within two components. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0047] This invention provides a needle assembly module, a puncture actuator, and a surgical robot, suitable for retinal vascular injection and subretinal injection in fundus microsurgery. The puncture actuator is an end effector adapted to an ophthalmic surgical robot, used to directly deliver therapeutic agents to the subretinal layer for subretinal injection; it can also be used for injection into retinal vessels, which helps to treat diseases at their root.

[0048] Please refer to Figures 1 to 11 This invention provides a needle assembly module. The needle assembly module 1 includes a needle tip 1-1, an inner tube 1-2, an outer tube 1-3, a force sensing element 1-4, a drug injection microtube 1-5, and a mounting frame 1-6. The outer tube 1-3 is inserted into the front end of the mounting frame 1-6. At least a portion of the inner tube 1-2 is slidably connected to the outer tube 1-3. The inner tube 1-2 is concentrically constrained by the outer tube 1-3 during its extension. The needle tip 1-1 and the inner tube 1-2 are concentrically arranged and integrally formed. The connection between the needle tip 1-1 and the inner tube 1-2 is a bent section. At least one force sensing element 1-4 is installed on the outer tube 1-3. Drug injection channels are provided inside the needle tip 1-1 and the inner tube 1-2. The base of the inner tube 1-2 is connected to the drug injection microtube 1-5. The other end of the drug injection microtube 1-5 is connected to an external syringe, allowing for manual drug injection.

[0049] In this embodiment, the needle tip 1-1 and the inner tube 1-2 are integrally formed, resulting in a robust structure. This avoids traces left during the adhesive bonding process and prevents issues such as weak adhesion and uneven overall rigidity of the inner tube 1-2. It also facilitates easier installation and adjustment of the pre-bending angle of the inner tube 1-2. The needle tip 1-1 and the inner tube 1-2 can slide relative to each other along the inner wall of the outer tube 1-3, facilitating the release of the needle tip. The inner diameter of the injection channel can be 0.06 mm.

[0050] Optionally, the needle tip 1-1 and the inner tube 1-2 are made of shape memory material, preferably nickel-titanium alloy.

[0051] Optionally, several force-sensing elements 1-4 are fixed in a ring array to the outer wall of the outer tube 1-3 near the end of the needle tip 1-1. Figure 11For example, in this embodiment, three force-sensing elements 1-4 are bonded to the outer tube 1-3 in a ring array, with an included angle of 120 degrees between adjacent force-sensing elements 1-4. The force-sensing elements 1-4 can be selected as Bragg fiber grating sensors. This needle assembly module 1 integrates the force-sensing elements 1-4, and its overall diameter is less than 0.5 mm, allowing it to be inserted into the eye using a 23G medical scleral cannula. This ensures the reliability of the integrated needle tip, making it particularly suitable for subretinal injection.

[0052] Optionally, the manufacturing process of the needle assembly module 1 can be carried out in the following way: First, on the 0.2mm diameter nickel-titanium tube (inner tube 1-2), by removing part of the nickel-titanium material, the diameter of a part of the nickel-titanium tube is reduced to 0.1mm (needle tip 1-1). Then, on a customized mold, a part of the 0.2mm diameter nickel-titanium tube (inner tube 1-2) is pre-bent and heated to shape.

[0053] Therefore, the needle tip 1-1 and inner tube 1-2 of this needle assembly module 1 are designed as a single unit, which effectively ensures the reliability of the connection between the needle tip 1-1 and the inner tube 1-2 without relying on welding or bonding. Furthermore, this integrated machining method for the needle tip 1-1 and inner tube 1-2 can also be used on straight, rigid needles, allowing the portion entering the eye to have varying thicknesses, thus ensuring overall rigidity. This needle assembly module 1 integrates the needle with the intraocular flexible arm based on the concentric tube principle, solving the reliability problems associated with welding or gluing connections between the needle and the concentric tube.

[0054] When not in use, the needle tip 1-1 of the needle assembly module 1 can retract into the outer tube 1-3 along with the inner tube 1-2, reducing the overall diameter to less than 0.52 mm, allowing for smooth passage through a 23G scleral cannula. This not only ensures the hygiene of the needle tip 1-1 but also protects it from external force, preventing changes in the bending of the needle tip 1-1 that could lead to complications during surgery. Furthermore, it protects the needle tip 1-1 before it enters the eye. Therefore, this needle assembly module 1 solves the size problem of intraocular instruments integrating force sensing elements and concentric tube flexible arms, enabling them to enter the eye through a medical 23G scleral cannula.

[0055] The bending angle of the needle tip 1-1 is divided into the following steps: Before entering the 23G scleral cannula, the inner tube 1-2 is completely retracted into the outer tube 1-3. When entering the eye, the inner tube 1-2 extends out from the outer tube 1-3. Since part of the inner tube 1-2 is pre-bent, as the extension length increases, the angle of the front needle tip 1-1 relative to the outer tube 1-3 also gradually increases. In addition to adjusting the bending angle of the needle tip 1-1, the inner tube 1-2 and the outer tube 1-3 can also be rotated simultaneously to adjust the direction.

[0056] In some embodiments, the degree of bending at the end of the inner tube 1-2 of the needle assembly module 1 is controllable and can be adjusted by a pre-bending angle. The diameter of the needle tip 1-1 is 0.1 mm, the diameter of the inner tube 1-2 is 0.2 mm, and a bent section with a length of 0.2 mm is provided at the connection between the inner tube 1-2 and the needle tip 1-1. The diameter of the bent section at the connection between the needle tip 1-1 and the inner tube 1-2 is transitioned from 0.2 mm to 0.1 mm through grinding.

[0057] Preferably, the insertion end of the needle tip 1-1 is processed into a sharp tip by laser processing and fine grinding.

[0058] In this embodiment, the tip of the needle 1-1 has a sharp point. During surgery, the inner tube 1-2 retracts into the outer tube 1-3 and enters the eye. After entering the eye, the bending angle of the needle tip 1-1 is adjusted according to the position of the blood vessels and the retina, further adjusting the angle between the needle tip 1-1 and the retina. During puncture, all joints on the telecentric motion (RCM) mechanism and actuator drive unit of the fundus surgery robot move in synergistic motion to puncture at a small angle in the direction of the needle tip, achieving precise tilting insertion into the blood vessel or under the retinal layer, and improving the accuracy of adjusting the retinal puncture angle.

[0059] It should be noted that when inserting the needle tip 1-1 of the needle assembly module 1 into a blood vessel, it generally needs to be inserted at a certain angle. If it is inserted vertically into the blood vessel, it is very easy to puncture the entire blood vessel.

[0060] The needle assembly module 1 provided by this invention can directly inject drugs into the subretinal layer of tiny lesions, successfully overcoming the physiological limits of the human hand and achieving the therapeutic goal. The needle assembly module 1 utilizes a concentric tube structure for flexible adjustment of the puncture angle, while ensuring the accuracy and stability of the puncture trajectory during insertion, as well as the stability of the overall structure. Furthermore, the needle assembly module 1 integrates the needle tip 1-1 and the inner tube 1-2 into a single structure, allowing both the needle tip 1-1 and the inner tube 1-2 to rotate simultaneously at the same angle, thereby adjusting the direction of insertion into the blood vessel. Furthermore, the needle tip 1-1 and the curved section of the inner tube 1-2 within the outer tube 1-3 of the needle assembly module 1 have a preset curvature, and this curvature is constant. Based on the working principle of concentric tubes, as the needle tip 1-1 and the inner tube 1-2 extend, the needle tip 1-1 and the inner tube 1-2 protruding from the outer tube 1-3 gradually change from a straight line to a curved state, thereby ensuring precise adjustment of the bending angle of the needle assembly module 1. Force sensing is achieved through the force sensing element 1-4, thus realizing precise retinal puncture injection.

[0061] For example, the retinal vascular injection device and its injection method for ophthalmic surgical robots disclosed in the inventor's previous Chinese patent application (publication number CN110368184A) lack precision in adjusting the angle of the needle tip, and the reliability of the needle tip adhering to the inner tube is very low, making leakage and needle drop very easy. The needle assembly module 1 provided by this invention solves the problem of adjusting the angle of retinal puncture. It integrates a high-precision intraocular flexible arm and force sensing elements, enabling precise depth sensing through force sensing elements 1-4 during subretinal injection surgery. This allows for a longer puncture path, avoids drug reflux, and thus improves the success rate of the surgery.

[0062] Compared to existing syringe devices, the needle tip bending angle of the needle tube module 1 provided by the present invention can be adjusted in two ways: the first is by adjusting the pre-bending degree of the inner tube 1-2 itself, and the second is by constraining the length of the inner tube 1-2 extending out of the outer tube 1-3. In this case, the pre-bending degree is determined in advance, and the bending angle is determined by the extension length and the pre-bending degree.

[0063] In addition, please refer to Figure 1 , Figure 2 , Figure 3 and Figure 4 This invention also provides a force-sensing puncture actuator, including the aforementioned needle assembly module 1, an inner tube feeding module 2, a rotation module 3, and an actuator mounting base 4. Mounting brackets 1-6 are mounted on the front end of the rotation module 3, the base of the inner tube 1-2 is mounted on the front end of the inner tube feeding module 2, the needle assembly module 1 is mounted on the inner tube feeding module 2 and fed under the drive of the inner tube feeding module 2, the inner tube feeding module 2 is mounted on the front of the rotation module 3, the needle assembly module 1 and the inner tube feeding module 2 rotate under the drive of the rotation module 3, and the rotation module 3 is mounted on the actuator mounting base 4 located at the rear of the inner tube feeding module 2.

[0064] In some embodiments, the inner tube feeding module 2 includes a power drive unit, a lead screw 2-5, a lead screw nut 2-6, an inner tube connector 2-7, and a slide rail 2-8. The slide rail 2-8 is mounted on the mounting bracket 1-6. One end of the lead screw 2-5 is rotatably mounted on the front of the mounting bracket 1-6, and the other end of the lead screw 2-5 is connected to the power drive unit mounted on the mounting bracket 1-6. The lead screw nut 2-6 is mounted on the lead screw 2-5. The slide rail 2-8 is arranged parallel to the lead screw 2-5. The lower part of the inner tube connector 2-7 is slidably mounted on the slide rail 2-8, and the side of the inner tube connector 2-7 is connected to the lead screw nut 2-6. The inner tube connector 2-7 is connected to the inner tube 1-2. Under the drive of the lead screw nut 2-6, the inner tube connector 2-7 moves linearly along the slide rail 2-8, thereby driving the extension and retraction of the inner tube 1-2.

[0065] With this configuration, the inner tube connector 2-7 connects the inner tube 1-2, the lead screw nut 2-6, and the slide rail 2-8, allowing the inner tube 1-2 to extend and retract relative to the outer tube 1-3 along the slide rail 2-8.

[0066] Optionally, the power drive unit includes a first drive mechanism 2-1, a first pulley 2-2 drivenly connected to the first drive mechanism 2-1, and a second pulley 2-4 connected to the first pulley 2-2 via a conveyor belt 2-3. The second pulley 2-4 is connected to a lead screw 2-5.

[0067] In this embodiment, the first pulley 2-2 is connected to the output shaft of the first drive mechanism 2-1. The first drive mechanism 2-1 drives the first pulley 2-2 to rotate. The first pulley 2-2 drives the second pulley 2-4 to rotate via the conveyor belt 2-3. The second pulley 2-4 drives the lead screw 2-5 to rotate, thereby causing the lead screw nut 2-6 to move up and down. Thus, the first drive mechanism 2-1 transmits motion to the lead screw 2-5 via the synchronous belt 2-3, and then transmits the motion to the inner tube 1-2 via the lead screw 2-5, the lead screw nut 2-6, and the inner tube connector 2-7, causing it to extend and retract relative to the outer tube 1-3. The first drive mechanism 2-1 can be an AC servo motor.

[0068] Optionally, it also includes a tensioning member 2-9 installed at the rear of the mounting frame 1-6, a first drive mechanism 2-1 installed on the tensioning member 2-9, and a second pulley 2-4 installed at the other end of the lead screw 2-5; the tensioning member 2-9 is formed by two long strip plates fastened together, and two hollow shafts are provided at the fastening part, each hollow shaft is embedded with a spring, and the spring release force pushes the first pulley 2-2 outward, thereby achieving tensioning of the conveyor belt 2-3.

[0069] With this configuration, the tensioning member 2-9 and the mounting bracket 1-6 in this embodiment are connected to form a whole, and two springs are installed in the two hollow shafts at the connection position to provide tension to the conveyor belt 2-3.

[0070] In some embodiments, the rotating module 3 includes a second drive mechanism 3-3, which is mounted on the actuator mounting base 4. The output shaft of the second drive mechanism 3-3 is fitted with a rotating fastening nut 3-2, which is connected to the mounting bracket 1-6. The second drive mechanism 3-3 drives the mounting bracket 1-6 to rotate by rotating the fastening nut 3-2.

[0071] In this embodiment, the second drive mechanism 3-3 is connected to the needle assembly module 1 and the inner tube feeding module 2 via the mounting bracket 1-6, thereby driving the needle assembly module 1 and the inner tube feeding module 2 to rotate, thus adjusting the orientation of the needle tip 1-1 so that the needle tip 1-1 is in the same plane as the target blood vessel. The second drive mechanism 3-3 can be an AC servo motor.

[0072] Optionally, the rotating module 3 also includes a bearing 3-1, which is mounted on the shaft at the connection between the mounting bracket 1-6 and the actuator mounting base 4.

[0073] With this setup, since AC servo motors have poor capacity to withstand non-working loads, bearing 3-1 is used to support the entire actuator, which greatly reduces the non-working load on the second drive mechanism 3-3.

[0074] To meet the precision requirements of the inner tube feeding module 2 and the rotation module 3, each is equipped with an AC servo motor. Compared to ordinary motors, AC servo motors can directly drive components at low speeds, unlike traditional fixed-power motors which require speed reducers and other mechanisms to constrain and adjust speed, thus offering higher precision. In a stationary state, without current flowing, the motor self-locks through friction; equipped with a high-precision optical encoder, it achieves micron-level accuracy, while also providing position information for the surgical robot's speed control and motion compensation.

[0075] The inner tube feed module 2 has an accuracy of 1-2μm, and the rotation module 3 has a stroke of 270 degrees and an end-point oscillation accuracy of 2-3μm. As a high-precision surgical instrument, the deformation caused by the rigidity of the parts themselves cannot be ignored. Therefore, the actuator minimizes the bonding and assembly parts. For example, the mounting bracket 1-6 uses a custom-made one-piece molded 1060 aluminum alloy part, which meets the requirements of lightweight while ensuring rigidity. The needle tip 1-1 and the inner tube 1-2 are machined as a single piece, which facilitates installation and replacement and ensures the overall uniformity of rigidity of the inner tube 1-2 during feeding.

[0076] Meanwhile, since the tissue contact stress between the needle and the subretinal insertion point is much greater than the operational force during cannulation, the developed force sensing elements 1-4 must be integrated into the human eye. This invention uses a Bragg fiber grating sensor for micro-force sensing, which is unaffected by electrical noise, easy to sterilize, and has good biocompatibility. An adaptive compensation algorithm can accurately obtain the value of minute forces, thus achieving two-dimensional force sensing.

[0077] The overall design of the puncture actuator takes into account the center of gravity position and is continuously optimized to make the center of gravity close to the central axis position. This ensures that when the end rotates, there will be no additional torque due to the deviation of the center of gravity, and the whole can operate more stably.

[0078] In addition, please refer to Figure 6The present invention also provides a surgical robot, including the above-mentioned puncture actuator, and further including a linear guide module 5. The actuator mounting base 4 is mounted on the linear guide module 5. The linear guide module 5 is connected to the telecentric motion (RCM) mechanism of the ophthalmic surgical robot. The linear guide module 5 is used to drive the actuator mounting base 4 to move, and the entire puncture actuator is driven to move through the linear guide module 5.

[0079] In some embodiments, the linear guide module 5 includes a sliding platform 5-1, a linear guide rail 5-2, and a third drive mechanism 5-3. The actuator mounting base 4 is mounted on the sliding platform 5-1, and the sliding platform 5-1 is slidably mounted on the linear guide rail 5-2 by bolts. The third drive mechanism 5-3 is connected to the linear guide rail 5-2. The third drive mechanism 5-3 drives the actuator mounting base 4 and its components to perform precise movements. The third drive mechanism 5-3 can be a stepper motor.

[0080] The working principle of this invention is as follows:

[0081] The needle module 1 is inserted into the patient's eyeball by the movement of the surgical robot's manipulator arm. Then, the robot's telecentric motion (RCM) mechanism guides the needle to the vicinity of the target area for coarse positioning.

[0082] At this time, the first drive mechanism 2-1 starts to move and releases the needle tip 1-1. Then, through the combined action of the linear guide module 5 and the second drive mechanism 3-3, an angle between 20 and 90 degrees can be formed, which can be adjusted by the doctor.

[0083] The host computer executes the subretinal or retinal vessel puncture program, controls the linear guide module 5 and the robot manipulator arm to move, and through the coordinated movement of all joints on the robot's telecentric motion (RCM) mechanism and the drive unit on the actuator, the linear guide module 5 punctures the subretinal or retinal vessel along the direction of the needle tip 1-1. At the same time, the force sensing element 1-4 on the outer tube 1-3 detects the puncture force. When the force reaches the preset value, the puncture stops and then the injection is performed.

[0084] This invention ensures the stability of the connection through the integrated design of the needle tip 1-1 and the inner tube 1-2. Furthermore, this invention eliminates one degree of freedom for the actuator's longitudinal movement. In the prior art, the actuator has one linear degree of freedom, the guide rail provides another linear degree of freedom, and the motor feeding the inner tube 1-2 provides another longitudinal degree of freedom. This invention eliminates the intermediate rotary feed degree of freedom, retaining only two longitudinal degrees of freedom: one is the feed of the first drive mechanism 2-1, and the other is the longitudinal feed degree of freedom provided by the linear guide rail module 5.

[0085] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A puncture actuator, characterized in that, Includes a syringe assembly module, which includes: needle tip; The inner tube is connected to the needle tip and is set as a curved section at the connection. The inner tube is made of shape memory material and is set with a pre-bending angle. The needle tip and the inside of the inner tube are set with drug injection channels. The outer tube, at least part of the inner tube, is slidably connected inside the outer tube. The needle tip and the inner tube can extend and retract inside the outer tube, and the needle tip, the inner tube, and the outer tube can rotate. Force sensing element, installed on the outer tube; The needle tip and inner tube are integrated into one structure. The needle tip has a sharp point and is made of shape memory material. It also includes an injection tube, which is connected to the inner tube and communicates with the injection channel; Several force sensing elements are fixed in a ring array to the outer wall of the outer tube near the tip of the needle; The puncture actuator also includes: The inner tube feed module is connected to the inner tube and is used to drive the inner tube and the needle tip to perform telescopic movements inside the outer tube. The rotating module, connected to the inner tube feed module, is used to drive the inner tube feed module and the needle assembly module connected to the inner tube feed module to rotate, so that the needle tip, inner tube and outer tube rotate. The syringe module also includes a mounting bracket, which is mounted on the rotating module. The rotating module drives the mounting bracket to rotate, and the outer tube is inserted into the mounting bracket. The inner tube feeding module includes a power drive unit, a lead screw, a lead screw nut, an inner tube connector, and a slide rail. The slide rail is mounted on a mounting frame. One end of the lead screw is rotatably mounted on the mounting frame, and the other end is connected to the power drive unit mounted on the mounting frame. The lead screw nut is mounted on the lead screw, and the slide rail is arranged parallel to the lead screw. The inner tube connector is slidably mounted on the slide rail and connected to the lead screw nut. The inner tube connector is connected to the inner tube and moves linearly along the slide rail under the drive of the lead screw nut, thereby driving the inner tube to perform telescopic movement within the outer tube. The power drive unit includes a first drive mechanism, a first pulley driven by the first drive mechanism, and a second pulley connected to the first pulley via a conveyor belt. The second pulley is connected to the lead screw. The rotating module includes a second drive mechanism, which is mounted on the actuator mounting base. The output shaft of the second drive mechanism is equipped with a rotating fastening nut, which is connected to the mounting bracket. The second drive mechanism drives the mounting bracket to rotate through the rotating fastening nut.

2. The puncture actuator according to claim 1, characterized in that, The force sensing element is a Bragg fiber grating sensor.

3. A surgical robot, characterized in that, The device includes the puncture actuator according to any one of claims 1-2, and further includes a linear guide module, wherein the puncture actuator is mounted on the linear guide module, and the linear guide module is used to drive the puncture actuator to move.

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