MRI-Compatible Cranial Nerve Puncture Robot

Abstract

MRI-compatible cranial nerve puncture robot, which relates to the fields of medical robots and image-guided surgery technology. The present invention solves the accuracy problem caused by the lack of real-time imaging feedback during the operation in the existing brain puncture surgery, especially when facing challenges such as brain deformation after skull opening and deformation of the puncture needle under force. Both ends of the semi-circular rack are respectively connected to the upper parts of the Pitch axis driven rotary assembly and the Pitch axis driving rotary assembly. The Pitch axis driven rotary assembly and the Pitch axis driving rotary assembly are respectively connected to two moving platforms on the mounting base plate. An arc track moving assembly is installed in the middle of the semi-circular rack, and a base roll rotating assembly is installed on the arc track moving assembly. The 2DOF puncture needle is installed on the base roll rotating assembly. The present invention is used to improve the hit rate of brain puncture surgery, simplify the surgical process, and reduce the operation time and risk.

Description

Technical Field

[0001] The present invention relates to the technical fields of medical robots and image-guided surgery, and particularly to a brain puncture robot system suitable for a magnetic resonance imaging (MRI) environment, specifically to an MRI-compatible cranial nerve puncture robot. Background Art

[0002] With the rapid development of modern medical imaging technology, magnetic resonance imaging (MRI), as a high-resolution and non-invasive imaging method, has become one of the key tools in the diagnosis and treatment of brain diseases. In neurosurgery, brain puncture technology provides a relatively safe and effective minimally invasive surgical method by precisely locating the lesion area. Compared with traditional craniotomy, brain puncture surgery can reduce the patient's postoperative recovery time and lower the surgical risk. However, existing brain puncture technologies still face many challenges and technical bottlenecks in practical applications.

[0003] Firstly, although MRI can provide high-resolution soft tissue images and help plan the puncture path preoperatively, it is still difficult to update the image in real time during the operation and confirm the lesion location. Current brain puncture surgeries usually rely on preoperative images for path planning, and it is difficult to update the real-time image inside the nuclear magnetic resonance scanner during the actual puncture process. This limitation makes the surgical process lack an adequate feedback mechanism and unable to make dynamic adjustments according to the intraoperative situation, thus increasing the risk and difficulty of the surgery.

[0004] Secondly, after the skull is opened during the operation, the brain tissue may undergo significant deformation, sometimes up to 20 millimeters, and the deformation does not necessarily occur in the direction of gravity. This unforeseen tissue deformation further increases the complexity of the surgery and may cause the failure of the preoperatively planned puncture path. In addition, the puncture needle may deform due to tissue resistance during the puncture process, resulting in deviations in the puncture angle and depth. Current puncture devices lack a real-time intraoperative image guidance and puncture needle position confirmation mechanism, making the surgical process almost "blind" without any image-based feedback and increasing the risk of misoperation.

[0005] Finally, existing surgical robot systems and surgical instruments have not fully achieved compatibility with MRI devices. The MRI environment poses strict requirements on the materials, dimensions, and electromagnetic characteristics of surgical devices. Traditional surgical robot systems often cannot achieve precise operation in the narrow MRI scanning space, and the electromagnetic interference of the devices may affect the imaging quality of MRI. In addition, current brain puncture robots mostly use electric motors for driving, which have relatively large electromagnetic interference and are difficult to use in the MRI environment, thus limiting their clinical applications.

[0006] Based on the above technical background, it is particularly important to develop a brain puncture robot that can work safely and effectively in the MRI environment. Such a robot should have good nuclear magnetic compatibility, be able to achieve precise multi-degree-of-freedom movement in a narrow space, and be able to sense the force feedback of the puncture needle in real time during the operation, so as to improve the accuracy and safety of the operation. Summary of the Invention

[0007] The purpose of the present invention is to solve the accuracy problem caused by the lack of real-time imaging feedback during the operation in the existing brain puncture surgery, especially when facing challenges such as brain deformation after skull opening and puncture needle force deformation, and further provide an MRI-compatible cranial nerve puncture robot.

[0008] The technical solution of the present invention is as follows:

[0009] An MRI-compatible cranial nerve puncture robot, which comprises a 2-DOF mobile chassis 1, a 3-DOF RCM mechanism 2 and a 2-DOF puncture needle 3. The 2-DOF mobile chassis 1 includes a mounting base plate 11 and two mobile platforms 12. Two mobile platforms 12 arranged side by side are respectively installed on the left and right sides of the upper surface of the mounting base plate 11. The 3-DOF RCM mechanism 2 includes a Pitch axis driven rotary assembly 21, a Pitch axis driving rotary assembly 22, a semi-circular rack 23, an arc track moving assembly 24 and a base roll rotating assembly 25. A semi-circular rack 23 is arranged above the 2-DOF mobile chassis 1. The two ends of the semi-circular rack 23 are respectively connected to the upper parts of the Pitch axis driven rotary assembly 21 and the Pitch axis driving rotary assembly 22. The lower parts of the Pitch axis driven rotary assembly 21 and the Pitch axis driving rotary assembly 22 are respectively connected to the two mobile platforms 12. An arc track moving assembly 24 is installed in the middle of the semi-circular rack 23. A base roll rotating assembly 25 is installed on the arc track moving assembly 24. The 2-DOF puncture needle 3 is installed on the base roll rotating assembly 25.

[0010] Further, each mobile platform 12 includes a mobile platform lead screw nut mechanism 121, a mobile platform linear guide mechanism 122, and a lifting link mechanism 123. The mobile platform lead screw nut mechanism 121 and the mobile platform linear guide mechanism 122 are arranged side by side from outside to inside on the mounting base plate 11. The lifting link mechanism 123 includes a lifting platform 1231, a first lifting link 1232, a second lifting link 1233, a first link bearing seat 1234, and a second link bearing seat 1235. The lifting platform 1231 is located above the mobile platform 12. One end of the first lifting link 1232 is rotatably connected to one end of the lifting platform 1231 through a connecting member, and the other end of the first lifting link 1232 is rotatably connected to the first link bearing seat 1234 through a connecting member. The link bearing seat 1234 is mounted on the upper surface of the slider of the mobile platform linear guide mechanism 122. One end of the second lifting link 1233 is rotatably connected to the other end of the lifting platform 1231 through a connecting member, and the other end of the second lifting link 1233 is rotatably connected to the second link bearing seat 1235 through a connecting member. The second link bearing seat 1235 is mounted on the upper surface of the lead screw nut of the mobile platform lead screw nut mechanism 121.

[0011] Further, the first lifting link 1232 and the second lifting link 1233 have the same structure. The first lifting link 1232 includes two lifting link bodies 12321, two link pin shafts 12322, and three link connecting blocks 12323. The two lifting link bodies 12321 are arranged side by side. The middle parts of the two lifting link bodies 12321 are connected by three link connecting blocks 12323 arranged at equal intervals. One end of the two lifting link bodies 12321 is rotatably connected to the lifting platform 1231 through a link pin shaft 12322, and the other end of the two lifting link bodies 12321 is connected to the first link bearing seat 1234 or the second link bearing seat 1235 through a ceramic bearing.

[0012] Further, the mobile platform lead screw nut mechanism 121 includes a mobile platform lead screw motor 1211, a mobile platform lead screw 1212, a mobile platform lead screw nut 1213, and two mobile platform lead screw bearing seats 1214. The mobile platform lead screw 1212 is horizontally arranged above the mounting base plate 11. The two ends of the mobile platform lead screw 1212 are respectively connected to the mounting base plate 11 through two mobile platform lead screw bearing seats 1214. One end of the mobile platform lead screw 1212 is connected to the mobile platform lead screw motor 1211. The mobile platform lead screw motor 1211 is mounted on the upper surface of the mounting base plate 11. The mobile platform lead screw nut 1213 is threadedly connected to the mobile platform lead screw 1212.

[0013] Further, the linear guide mechanism 122 of the moving platform includes a linear guide body 1221 of the moving platform, a three-hole slider 1222, two guide rail stoppers 1223, and three moving platform rollers 1224. The cross-section of the linear guide body 1221 of the moving platform is U-shaped. Two guiding protrusions arranged side by side along the length direction of the guide rail are provided on the upper parts of the inner side surfaces of the chute of the linear guide body 1221 of the moving platform. Two guide rail stoppers 1223 are respectively installed at both ends of the chute of the linear guide body 1221 of the moving platform. The three-hole slider 1222 is horizontally arranged above the linear guide body 1221 of the moving platform. Three moving platform rollers 1224 are arranged at equal intervals in sequence from front to back along the length direction of the slider below the three-hole slider 1222. Three roller pins are respectively inserted into the three inner holes of the three-hole slider 1222. The lower ends of the three roller pins are respectively connected to the three moving platform rollers 1224 through three ceramic bearings.

[0014] Further, the Pitch-axis driven rotary assembly 21 includes a left Pitch axis 211, a left Pitch-axis support 212, an upper plate 213 of the left support, and two left support side plates 214. The left Pitch-axis support 212 is an inverted T-shaped support. The left Pitch-axis support 212 is installed on the upper surface of the left lifting platform 1231. The middle part of the left Pitch axis 211 is installed in the shaft hole of the left Pitch-axis support 212 through a ceramic bearing. The two left support side plates 214 are respectively arranged vertically opposite on both sides of the upper part of the left Pitch-axis support 212. The two left support side plates 214 are respectively fixedly connected to both ends of the left Pitch axis 211. An upper plate 213 of the left support is provided above the two left support side plates 214. Both sides of the bottom of the upper plate 213 of the left support are respectively connected to the tops of the two left support side plates 214. The top end of the upper plate 213 of the left support is connected to the lower left end of the semi-circular rack 23.

[0015] Further, the Pitch-axis driving rotary assembly 22 includes a Pitch-axis worm and gear mechanism, a right Pitch axis 221, an upper plate 222 of the right support, two right Pitch-axis supports 223, and two right support side plates 224. The right Pitch-axis support 223 is an L-shaped shaft support. The two right Pitch-axis supports 223 are vertically and symmetrically installed on the upper surface of the right lifting platform 1231. Both ends of the right Pitch axis 221 are respectively installed in the shaft holes of the two right Pitch-axis supports 223 through two ceramic bearings. The two right support side plates 224 are respectively arranged vertically opposite on the outer sides of the upper parts of the two right Pitch-axis supports 223. The two right support side plates 224 are respectively fixedly connected to both ends of the right Pitch axis 221. An upper plate 222 of the right support is provided above the two right support side plates 224. Both sides of the bottom of the upper plate 222 of the right support are respectively connected to the tops of the two right support side plates 224. The top end of the upper plate 222 of the right support is connected to the lower right end of the semi-circular rack 23;

[0016] The Pitch axis worm and gear mechanism includes a Pitch axis worm gear 225, a Pitch axis worm 226, a Pitch axis worm and gear motor 227, a Pitch axis worm and gear motor support 228, and a Pitch axis worm bearing block 229. The Pitch axis worm gear 225 is installed in the middle of the right Pitch axis 221. An inclined Pitch axis worm 226 is provided on the side of the Pitch axis worm gear 225. The end shaft section of the Pitch axis worm 226 is connected to the Pitch axis worm bearing block 229 through a ceramic bearing. The Pitch axis worm bearing block 229 is installed on the upper surface of the lifting platform 1231. The lower part of the Pitch axis worm 226 meshes with the Pitch axis worm gear 225. The head shaft section of the Pitch axis worm 226 is connected to the rotating shaft of the Pitch axis worm and gear motor 227. The Pitch axis worm and gear motor 227 is installed on the Pitch axis worm and gear motor support 228. The Pitch axis worm and gear motor support 228 is installed on the upper surface of the lifting platform 1231.

[0017] Further, the arc-shaped track moving component 24 includes a track slider 241, a front slider cover plate 242, a rear slider cover plate 243, a track motor 244, a backlash eliminator gear 245, two upper guide wheels 246, two groups of lower guide wheels 247, and a plurality of cover plate connection blocks 248. Both the front slider cover plate 242 and the rear slider cover plate 243 are circular arc-shaped plate structures. The front slider cover plate 242 and the rear slider cover plate 243 are vertically symmetrically arranged. On the upper and lower sides of the inner surfaces of the front slider cover plate 242 and the rear slider cover plate 243, a plurality of cover plate connection blocks 248 are respectively provided. The cover plate connection blocks 248 are connected to the front slider cover plate 242 and the rear slider cover plate 243 through connecting elements. The track slider 241 is installed on the upper part of the inner surface of the front slider cover plate 242 and the rear slider cover plate 243. The cross-section of the track slider 241 is an L-shaped block structure. On the rear side of the vertical section at the bottom of the track slider 241, two upper guide wheels 246 are evenly arranged along the length direction. An annular upper wheel groove is provided on the side surface of the upper guide wheel 246. The semi-circular rack 23 is arranged below the track slider 241. An arc-shaped protrusion matching the annular upper wheel groove is provided on the upper rear side of the semi-circular rack 23 along the length direction of the rack. On the front and rear sides at the bottom of the track slider 241, two pairs of coaxially arranged groups of lower guide wheels 247 are respectively provided. Two rollers in each group of lower guide wheels 247 are respectively rotatably connected to the front slider cover plate 242 and the rear slider cover plate 243. On the front and rear sides at the bottom of the track slider 241, arc-shaped guide grooves matching the two rollers in each group of lower guide wheels 247 are respectively provided. A circular rack body is provided on the upper front side of the semi-circular rack 23 along the length direction of the rack. Above the circular rack body, a backlash eliminator gear 245 meshing with the rack body is provided. The backlash eliminator gear 245 is installed on the rotating shaft of the track motor 244. Track motor installation holes are provided in the upper parts of the rear slider cover plate 243 and the track slider 241. The housing of the track motor 244 is installed in the track motor installation holes.

[0018] Further, the base roll rotation assembly 25 includes a base roll motor 251, a base roll driving spur gear 252, a base roll driven spur gear 253, a base roll rotating shaft 254, and a base roll bearing cover plate 255. A base roll shaft hole is formed in the middle of the slider front cover plate 242. The base roll bearing cover plate 255 is installed on the front surface of the slider front cover plate 242. The shaft hole of the slider front cover plate 242 and the base roll shaft hole are coaxially arranged. The base roll rotating shaft 254 is installed in the shaft hole of the slider front cover plate 242 through a ceramic bearing. The end of the base roll rotating shaft 254 is connected to the rotating shaft of the base roll driven spur gear 253. The base roll driven spur gear 253 meshes with the base roll driving spur gear 252. The rotating shaft of the base roll driving spur gear 252 is connected to the rotating shaft of the base roll motor 251. Base roll motor mounting holes are formed in the upper parts of the slider rear cover plate 243 and the track slider 241. The housing of the base roll motor 251 is installed in the base roll motor mounting holes.

[0019] Further, the 2DOF puncture needle includes a puncture needle 31, a puncture needle lifting mechanism 32, and a puncture needle rotating mechanism 33. The puncture needle lifting mechanism 32 includes a puncture needle lifting bracket 321, a puncture needle lead screw nut mechanism 322, a puncture needle linear guide 323, and a puncture needle lifting motor 324. The puncture needle lifting bracket 321 is vertically arranged. A base roll rotating shaft hole is provided in the middle of the puncture needle lifting bracket 321. A vertically arranged puncture needle lead screw nut mechanism 322 is installed on the front surface of the puncture needle lifting bracket 321. The lower end of the lead screw of the puncture needle lead screw nut mechanism 322 is connected to the rotating shaft of the puncture needle lifting motor 324. The housing of the puncture needle lifting motor 324 is installed on the front surface of the puncture needle lifting bracket 321. A puncture needle linear guide 323 is provided on the side of the puncture needle lead screw nut mechanism 322. The lead screw nut of the puncture needle lead screw nut mechanism 322 is connected to the slider of the puncture needle linear guide 323;

[0020] The puncture needle rotation mechanism 33 includes a puncture needle rotation bracket 331, a puncture needle driving spur gear 332, a puncture needle driven spur gear 333, and a puncture needle rotation motor 334. The puncture needle rotation bracket 331 is horizontally arranged on the side of the needle lead screw nut mechanism 322. The puncture needle rotation bracket 331 is installed on the slider of the puncture needle lead screw nut mechanism 322. A puncture needle driving spur gear 332 is provided below the puncture needle rotation bracket 331. The rotating shaft of the puncture needle driving spur gear 332 passes through the puncture needle rotation bracket 331 and is connected to the rotating shaft of the puncture needle rotation motor 334. The housing of the puncture needle rotation motor 334 is installed on the upper surface of the puncture needle rotation bracket 331. A puncture needle driven spur gear 333 is provided on the side of the puncture needle driving spur gear 332. The puncture needle driven spur gear 333 meshes with the puncture needle driving spur gear 332. The rotating shaft of the puncture needle driven spur gear 333 is installed on the puncture needle rotation bracket 331 through a ceramic bearing. The rotating shaft of the puncture needle driven spur gear 333 is a hollow shaft. The upper part of the hollow shaft passes through the puncture needle rotation bracket 331 and the outer surface of the extended part is processed with an external thread. The puncture needle 31 includes a puncture needle body and a puncture needle locking nut. The puncture needle body is inserted into the inner hole of the hollow shaft from top to bottom. The puncture needle locking nut is sleeved on the upper part of the puncture needle body. The puncture needle body is fixedly connected to the upper part of the hollow shaft through the puncture needle locking nut.

[0021] The present invention has the following effects compared with the prior art:

[0022] 1. MRI compatibility and electromagnetic interference suppression:

[0023] Advantages: The robot system uses non-metallic materials (such as PEEK and POM), as well as piezoelectric drive technology, to ensure safe operation in the MRI environment.

[0024] Features: Through special shielding design, the impact on the MRI imaging quality is reduced, ensuring the clarity and signal-to-noise ratio of the imaging.

[0025] 2. Real-time imaging and positioning:

[0026] Advantages: Real-time MRI imaging is achieved during the operation, providing accurate feedback on the position of the puncture needle for the doctor and ensuring the accuracy of the puncture path.

[0027] Features: Through seamless integration with the MRI device, the robot can provide continuous image updates during the operation, ensuring real-time monitoring of the positional relationship between the puncture needle and the lesion area during the operation.

[0028] 3. High-precision puncture operation:

[0029] Advantages: The design of the fully piezoelectric drive structure with 7 degrees of freedom (DOF) ensures precise operation of the robot in a narrow space.

[0030] Features: Through the optimized RCM (remote central motion) mechanism design, the robot can achieve full coverage of the puncture needle at the back of the patient's brain, improving the flexibility and precision of the operation.

[0031] 4. Force perception and control:

[0032] Advantages: Through the integrated fiber grating (FBG) sensor, real-time monitoring and feedback of contact force during the puncture process can be achieved, ensuring precise control of the interaction between the puncture needle and brain tissue.

[0033] Features: FBG sensors can sense tiny force changes during puncture to avoid damage to surrounding healthy tissues.

[0034] 5. Dynamic adaptability and security:

[0035] Advantages: The robot can adjust the puncture path according to real-time MRI monitoring during surgery, adapt to slight deformation of brain tissue, and improve the flexibility and safety of surgery.

[0036] Features: Dynamic path planning is performed through intelligent algorithms to ensure that the puncture needle can accurately reach the lesion area while reducing surgical risks.

[0037] 6. Minimally invasive surgery:

[0038] Advantages: Through precise puncture path planning and execution, surgical trauma is reduced and the patient's postoperative recovery is accelerated.

[0039] Features: The diameter of the puncture needle is ≤2mm, ensuring the implementation of minimally invasive surgery and reducing the trauma caused by craniotomy.

[0040] Key performance indicators

[0041] MRI compatibility: The robot can work in a 3 Tesla magnetic field, and the signal-to-noise ratio attenuation of the MRI machine caused by the manipulator does not exceed 10%.

[0042] Positioning accuracy: The end repeat positioning accuracy reaches 0.3mm, and the puncture operation accuracy is better than 1.0mm under MRI image navigation.

[0043] Force sensing accuracy: The contact force sensor has a resolution better than 0.5N and a measuring range ≥5N.

[0044] Motion control error: The motion control error of the robot ablation end is less than 0.2mm, and the rotation control error is less than 1°.

[0045] Structural size: The overall design of the robot is compact and adapts to the space limitations inside the MRI scanning room.

[0046] Operational convenience: By means of an intuitive user interface and a simple operation process, the convenience of surgical operations is improved.

[0047] Through the realization of the above-mentioned advantages, features and performance indicators, the present invention can significantly improve the accuracy and safety of neurosurgical operations, reduce surgical risks, and shorten the recovery time of patients, which is an important progress in the field of medical robot technology in neurosurgery. Brief Description of the Drawings

[0048] Figure 1 is an axonometric view of the MRI-compatible cranial nerve puncture robot of the present invention; Figure 2 is a front view of the MRI-compatible cranial nerve puncture robot of the present invention; Figure 3 is Figure 2 a sectional view taken along A-A; Figure 4 is a top view of the MRI-compatible cranial nerve puncture robot of the present invention; Figure 5 is Figure 3 a sectional view taken along B-B; Figure 6 is Figure 3 a sectional view taken along C-C; Figure 7 is Figure 2 a sectional view taken along D-D; Figure 8 is a top view of the chassis of the present invention; Figure 9 is Figure 8 a sectional view taken along E-E; Figure 10 is Figure 8 a sectional view taken along F-F; Figure 11 is Figure 8 a sectional view taken along G-G; Figure 12 is a front view of the annular guide rail of the present invention; Figure 13 is a top view of the annular guide rail of the present invention; Figure 14 is a side view of the annular guide rail of the present invention; Figure 15 is Figure 14 a sectional view taken along H-H; Figure 16 is Figure 14 a sectional view taken along I-I.

[0049] In the figure: 1. 2-DOF mobile chassis; 11. Installation base plate; 12. Mobile platform; 121. Mobile platform lead screw nut mechanism; 1211. Mobile platform lead screw motor; 1212. Mobile platform lead screw; 1213. Mobile platform lead screw nut; 1214. Mobile platform lead screw bearing seat; 122. Mobile platform linear guide rail mechanism; 1221. Mobile platform linear guide rail body; 1222. Three-hole slider; 1223. Guide rail stopper; 1224. Mobile platform roller; 123. Lifting link mechanism; 1231. Lifting platform; 1232. First lifting link; 12321. Lifting link body; 12322. Link pin shaft; 12323. Link connection block; 1233. Second lifting link; 1234. First link bearing seat; 1235. Second link bearing seat; 2. 3-DOF RCM mechanism; 21. Pitch axis driven rotary assembly; 211. Left Pitch axis; 212. Left Pitch axis support; 213. Upper plate of left support; 214. Side plate of left support; 22. Pitch axis driving rotary assembly; 221. Right Pitch axis; 222. Upper plate of right support; 223. Right Pitch axis support; 224. Side plate of right support; 225. Pitch axis turbine; 226. Pitch axis worm; 227. Pitch axis turbine worm motor; 228. Pitch axis turbine worm motor support; 229. Pitch axis worm bearing seat; 23. Semi-circular rack; 24. Arc track moving assembly; 241. Track slider; 242. Front cover plate of slider; 243. Rear cover plate of slider; 244. Track motor; 245. Backlash elimination gear; 246. Upper guide wheel; 247. Lower guide wheel; 248. Cover plate connection block; 25. Base roll rotation assembly; 251. Base roll motor; 252. Base roll driving spur gear; 253. Base roll driven spur gear; 254. Base roll rotating shaft; 255. Base roll bearing cover; 3. 2DOF puncture needle; 31. Puncture needle; 32. Puncture needle lifting mechanism; 321. Puncture needle lifting bracket; 322. Puncture needle lead screw nut mechanism; 323. Puncture needle linear guide rail; 324. Puncture needle lifting motor; 33. Puncture needle rotation mechanism; 331. Puncture needle rotation bracket; 332. Puncture needle driving spur gear; 333. Puncture needle driven spur gear; 334. Puncture needle rotation motor. Detailed implementation mode

[0050] Detailed implementation mode one: Combine Figures 1 to 16To describe this embodiment, a kind of MRI-compatible cranial nerve puncture robot of this embodiment includes a 2-DOF mobile chassis 1, a 3-DOF RCM mechanism 2 and a 2-DOF puncture needle 3. The 2-DOF mobile chassis 1 includes a mounting base plate 11 and two mobile platforms 12. On the upper surface of the mounting base plate 11, two mobile platforms 12 arranged side by side are respectively installed on the left and right sides. The 3-DOF RCM mechanism 2 includes a Pitch-axis driven rotary assembly 21, a Pitch-axis driving rotary assembly 22, a semi-circular rack 23, an arc track moving assembly 24 and a base roll rotating assembly 25. There is a semi-circular rack 23 above the 2-DOF mobile chassis 1. The two ends of the semi-circular rack 23 are respectively connected to the upper parts of the Pitch-axis driven rotary assembly 21 and the Pitch-axis driving rotary assembly 22. The lower parts of the Pitch-axis driven rotary assembly 21 and the Pitch-axis driving rotary assembly 22 are respectively connected to the two mobile platforms 12. An arc track moving assembly 24 is installed in the middle of the semi-circular rack 23. A base roll rotating assembly 25 is installed on the arc track moving assembly 24. The 2-DOF puncture needle 3 is installed on the base roll rotating assembly 25.

[0051] The motion ranges of the 7 joint degrees of freedom of the robot are as follows: the forward and backward movement is from -61 mm to 61 mm; the up and down lift is from 0 mm to 55 mm; the Pitch-axis rotation angle is from -20 degrees to 80 degrees; the angle of movement along the track is from -65 degrees to 65 degrees; the rotation range of the puncture needle base roll axis is from -180 degrees to 180 degrees; the feed stroke of the puncture needle is from 0 mm to 85 mm, and the final rotation of the puncture needle is infinitely rotatable from 0 degrees to 360 degrees.

[0052] The present invention provides a fully MRI-compatible brain puncture robot based on piezoelectric drive. The robot system has a 7-degree-of-freedom fully piezoelectric drive structure, which can realize high-precision brain puncture operations on the premise of meeting the spatial constraints of the MRI environment. The robot reduces the interference to the MRI imaging quality through optimized shielding technology, and at the same time integrates a multi-dimensional force sensing system based on fiber Bragg grating (FBG) sensors to realize real-time monitoring and feedback of the contact force during the puncture process. The present invention overcomes the limitations of the lack of intraoperative image guidance and real-time feedback in the prior art by performing real-time surgical navigation in the nuclear magnetic environment, and provides a safe and effective brain puncture solution.

[0053] By developing a surgical robot compatible with the MRI environment, the present invention not only improves the hit rate of brain puncture surgery, but also simplifies the surgical process, reduces the surgical time and risk, and provides important technical support for the application of medical robots in minimally invasive neurosurgery.

[0054] In the MRI-compatible cranial nerve puncture robot of the present invention, the robot structural parts and transmission parts are processed from PEEK engineering plastics, and the remaining non-critical parts are processed by combining POM engineering plastics with 3D printing; considering the nuclear magnetic interference of the motor, the drive element uses an ultrasonic motor (inverse piezoelectric effect); the fixing parts use nylon bolts and nuts, and the rest, including but not limited to ceramic bearings, plastic gaskets, carbon fiber, etc., are used to ensure nuclear magnetic compatibility. Without considering the sensors, this mechanism can achieve 100% non-metallic and 100% nuclear magnetic compatibility.

[0055] The MRI-compatible cranial nerve puncture robot of the present invention can enter the open scanning hole of the nuclear magnetic resonance scanner. After being imaged by the nuclear magnetic resonance scanner together with the patient's brain area, it is displayed on the doctor's operation terminal window. The puncture needle at the end of the robot can cover all areas of the patient's posterior brain, and can display the relative position between the puncture needle and the diseased brain tissue area in real time. There is direct visual image feedback on the minute deformation of the puncture needle and the offset of the diseased brain tissue, which greatly improves the accuracy during the operation. After planning the puncture path, the robot can automatically puncture the puncture needle into the designated area of the patient's brain tissue. Its unique RCM mechanism design enables the cranial puncture operation to meet the minimally invasive use requirements. After verification, under the limitation of a single craniotomy puncture point, the end of the puncture needle can reach most areas of the patient's posterior brain, greatly improving the fault tolerance and safety of the operation.

[0056] Specific embodiment two: Combining Figures 1 to 16 To illustrate this embodiment, each moving platform 12 of this embodiment includes a moving platform lead screw nut mechanism 121, a moving platform linear guide rail mechanism 122, and a lifting link mechanism 123. The moving platform lead screw nut mechanism 121 and the moving platform linear guide rail mechanism 122 are arranged side by side in sequence from the outside to the inside on the mounting base plate 11. The lifting link mechanism 123 includes a lifting platform 1231, a first lifting link 1232, a second lifting link 1233, a first link bearing seat 1234, and a second link bearing seat 1235. The lifting platform 1231 is located above the moving platform 12. One end of the first lifting link 1232 is rotatably connected to one end of the lifting platform 1231 through a connecting piece, and the other end of the first lifting link 1232 is rotatably connected to the first link bearing seat 1234 through a connecting piece. The link bearing seat 1234 is installed on the upper surface of the slider of the moving platform linear guide rail mechanism 122; one end of the second lifting link 1233 is rotatably connected to the other end of the lifting platform 1231 through a connecting piece, and the other end of the second lifting link 1233 is rotatably connected to the second link bearing seat 1235 through a connecting piece. The second link bearing seat 1235 is installed on the upper surface of the lead screw nut of the moving platform lead screw nut mechanism 121.

[0057] With such a setting, only the two connecting rods connected to the lead screw in the middle support and lift the platform 1231, and the connecting rods connected to the sliders on the outside only play a guiding role. The guide rail slider is designed with an in-built double-shaft linear guide rail. The entire moving platform is fixed on the bottom mounting base plate 11. The other components and connection relationships are the same as those in the first specific implementation manner.

[0058] Specific implementation manner three: Figures 1 to 16 To illustrate this implementation manner, the first lifting connecting rod 1232 and the second lifting connecting rod 1233 have the same structure. The first lifting connecting rod 1232 includes two lifting connecting rod bodies 12321, two connecting rod pin shafts 12322, and three connecting rod connection blocks 12323. The two lifting connecting rod bodies 12321 are arranged side by side. The middle parts of the two lifting connecting rod bodies 12321 are connected by three connecting rod connection blocks 12323 arranged at equal intervals. One end of the two lifting connecting rod bodies 12321 is rotatably connected to the lifting platform 1231 through the connecting rod pin shafts 12322, and the other end of the two lifting connecting rod bodies 12321 is connected to the first connecting rod bearing seat 1234 or the second connecting rod bearing seat 1235 through ceramic bearings.

[0059] The other components and connection relationships are the same as those in the first or second specific implementation manner.

[0060] Specific implementation manner four: Figures 1 to 16 To illustrate this implementation manner, the moving platform lead screw nut mechanism 121 of this implementation manner includes a moving platform lead screw motor 1211, a moving platform lead screw 1212, a moving platform lead screw nut 1213, and two moving platform lead screw bearing seats 1214. The moving platform lead screw 1212 is horizontally arranged above the mounting base plate 11. The two ends of the moving platform lead screw 1212 are respectively connected to the mounting base plate 11 through the two moving platform lead screw bearing seats 1214. One end of the moving platform lead screw 1212 is connected to the moving platform lead screw motor 1211, and the moving platform lead screw motor 1211 is installed on the upper surface of the mounting base plate 11. The moving platform lead screw nut 1213 is threadedly connected to the moving platform lead screw 1212.

[0061] With such a setting, this mechanism is driven by two identical lead screw nut mechanisms. The linear movement and lifting of the entire moving platform are achieved by driving the movement of the lead screw nuts. Since it is a parallel mechanism, when a single lead screw moves, the mechanism will show a state of under-degree of freedom and cannot complete any actions. Only when the two lead screw motors drive simultaneously and drive the lead screw nuts at the same speed, the lead screw nuts will move linearly at the same displacement speed. When the rotation directions of the two driving motors are the same, the moving directions of the two lead screw nuts are also the same, and the whole will move forward or backward; similarly, when the rotation directions of the two lead screw driving motors are opposite, the distance between the two lead screw nuts will change, causing the whole to lift or lower.

[0062] Due to the particularity of the parallel mechanism, when the mechanism moves or lifts alone, the rotational speeds of the two motors must be the same. When either motor experiences a step loss or for other reasons causes a large difference in the angles turned by the two motors, the upper plane will tilt or the mechanism will jam. This requires closed-loop control of these two motors at the control end, which raises requirements for subsequent kinematic control and motor speed detection, etc.

[0063] This structure is very simple but very effective. After combining the two degrees of freedom, the overall height of the mechanism is significantly reduced, leaving much more design space for the upper mechanism in the NMR space, and the overall volume of the mechanism is also reduced by a circle.

[0064] Other compositions and connection relationships are the same as those in the first, second, or third specific embodiments.

[0065] Specific embodiment five: Combining Figures 1 to 16 To illustrate this embodiment, the linear guide mechanism 122 of the moving platform in this embodiment includes a linear guide body 1221 of the moving platform, a three-hole slider 1222, two guide rail stoppers 1223, and three moving platform rollers 1224. The cross-section of the linear guide body 1221 of the moving platform is U-shaped. Two guiding protrusions arranged side by side along the length direction of the guide rail are provided on the upper parts of the two inner side surfaces of the chute of the linear guide body 1221 of the moving platform. Two guide rail stoppers 1223 are respectively installed at both ends of the chute of the linear guide body 1221 of the moving platform. The three-hole slider 1222 is horizontally arranged above the linear guide body 1221 of the moving platform. Three moving platform rollers 1224 are arranged at equal intervals in sequence from front to back along the length direction of the slider below the three-hole slider 1222. Three roller pins are respectively inserted into the three inner holes of the three-hole slider 1222, and the lower ends of the three roller pins are respectively connected to the three moving platform rollers 1224 through three ceramic bearings.

[0066] Other compositions and connection relationships are the same as those in the first, second, third, or fourth specific embodiments.

[0067] Specific embodiment six: Combining Figures 1 to 16To describe this embodiment, the Pitch axis driven rotary assembly 21 of this embodiment includes a left Pitch axis 211, a left Pitch axis support 212, an upper plate of the left support 213, and two left support side plates 214. The left Pitch axis support 212 is an inverted T-shaped support. The left Pitch axis support 212 is installed on the upper surface of the left lifting platform 1231. The middle of the left Pitch axis 211 is installed in the shaft hole of the left Pitch axis support 212 through a ceramic bearing. The two left support side plates 214 are vertically and oppositely arranged on both sides of the upper part of the left Pitch axis support 212. The two left support side plates 214 are respectively fixedly connected to both ends of the left Pitch axis 211. An upper plate of the left support 213 is provided above the two left support side plates 214. Both sides of the bottom of the upper plate of the left support 213 are respectively connected to the tops of the two left support side plates 214. The top of the upper plate of the left support 213 is connected to the lower left end of the semi-circular rack 23.

[0068] The other components and connection relationships are the same as those in the first, second, third, fourth, or fifth specific embodiments.

[0069] Specific embodiment seven: In combination with Figures 1 to 16 To describe this embodiment, the Pitch axis driving rotary assembly 22 of this embodiment includes a Pitch axis worm and gear mechanism, a right Pitch axis 221, an upper plate of the right support 222, two right Pitch axis supports 223, and two right support side plates 224. The right Pitch axis support 223 is an L-shaped shaft support. The two right Pitch axis supports 223 are vertically and symmetrically installed on the upper surface of the right lifting platform 1231. Both ends of the right Pitch axis 221 are respectively installed in the shaft holes of the two right Pitch axis supports 223 through two ceramic bearings. The two right support side plates 224 are vertically and oppositely arranged on the outer sides of the upper parts of the two right Pitch axis supports 223. The two right support side plates 224 are respectively fixedly connected to both ends of the right Pitch axis 221. An upper plate of the right support 222 is provided above the two right support side plates 224. Both sides of the bottom of the upper plate of the right support 222 are respectively connected to the tops of the two right support side plates 224. The top of the upper plate of the right support 222 is connected to the lower right end of the semi-circular rack 23;

[0070] The Pitch axis worm and worm gear mechanism includes a Pitch axis worm gear 225, a Pitch axis worm 226, a Pitch axis worm and worm gear motor 227, a Pitch axis worm and worm gear motor support 228, and a Pitch axis worm bearing seat 229. The Pitch axis worm gear 225 is installed in the middle of the right Pitch axis 221. An inclined Pitch axis worm 226 is provided on the side of the Pitch axis worm gear 225. The end shaft section of the Pitch axis worm 226 is connected to the Pitch axis worm bearing seat 229 through a ceramic bearing. The Pitch axis worm bearing seat 229 is installed on the upper surface of the lifting platform 1231. The lower part of the Pitch axis worm 226 meshes with the Pitch axis worm gear 225. The head shaft section of the Pitch axis worm 226 is connected to the rotating shaft of the Pitch axis worm and worm gear motor 227. The Pitch axis worm and worm gear motor 227 is installed on the Pitch axis worm and worm gear motor support 228, and the Pitch axis worm and worm gear motor support 228 is installed on the upper surface of the lifting platform 1231.

[0071] With such a setting, if a single-stage gear reduction is used, the size difference of the gears is too large to meet the requirement of size compatibility. If gears with a smaller module are used, there will be a problem that the accuracy is difficult to guarantee. Therefore, a worm and worm gear (the material is a combination of aluminum alloy and brass to reduce friction loss) is used to meet the requirement of a large reduction ratio. The other compositions and connection relationships are the same as those in the first, second, third, fourth, fifth, or sixth specific embodiments.

[0072] During the actual selection and processing, the price of the CSX90S3-60-BW-C2 motor is 12,000 yuan, which is too high. Finally, a cheaper motor CSX90S3-60-BW was optimally selected. The rated torque of this motor is only 0.75 N·m. Combined with the 1:30 reduction ratio of the worm and worm gear of this mechanism, it can drive the entire annular RCM mechanism to operate. Moreover, the worm and worm gear itself has mechanical self-locking, and there is no need to worry about the problem of the motor being stressed for a long time in the static state.

[0073] In terms of material selection, the peek material can meet the accuracy requirements through hobbing processing, and there is a self-lubricating property similar to that of ceramics between peek materials, and the wear during the transmission process is smaller, which is very suitable for use in the nuclear magnetic environment.

[0074] Specific embodiment eight: Combine Figures 1 to 16To describe this embodiment, the arc-shaped rail moving assembly 24 of this embodiment includes a rail slider 241, a front slider cover plate 242, a rear slider cover plate 243, a rail motor 244, a backlash-eliminating gear 245, two upper guide wheels 246, two groups of lower guide wheels 247, and a plurality of cover plate connection blocks 248. Both the front slider cover plate 242 and the rear slider cover plate 243 are circular arc-shaped plate structures. The front slider cover plate 242 and the rear slider cover plate 243 are vertically symmetrically arranged. On the upper and lower sides of the inner surfaces of the front slider cover plate 242 and the rear slider cover plate 243, a plurality of cover plate connection blocks 248 are respectively provided. The cover plate connection blocks 248 are connected to the front slider cover plate 242 and the rear slider cover plate 243 through connecting elements. The rail slider 241 is installed on the upper part of the inner surfaces of the front slider cover plate 242 and the rear slider cover plate 243. The cross-section of the rail slider 241 is an L-shaped block structure. On the rear side of the vertical section at the bottom of the rail slider 241, two upper guide wheels 246 are evenly arranged along the length direction. An annular upper wheel groove is formed on the side surface of the upper guide wheel 246. A semi-circular rack 23 is arranged below the rail slider 241. An arc-shaped protrusion matching the annular upper wheel groove is provided on the rear side of the upper part of the semi-circular rack 23 along the length direction of the rack. On the front and rear sides of the bottom of the rail slider 241, two groups of lower guide wheels 247 arranged coaxially are respectively provided. In each group of lower guide wheels 247, two rollers are respectively rotatably connected to the front slider cover plate 242 and the rear slider cover plate 243. Arc-shaped guide grooves matching the two rollers in each group of lower guide wheels 247 are respectively provided on the front and rear sides of the bottom of the rail slider 241. An annular rack body is provided on the front side of the upper part of the semi-circular rack 23 along the length direction of the rack. Above the annular rack body, a backlash-eliminating gear 245 meshing with the rack body is provided. The backlash-eliminating gear 245 is installed on the rotating shaft of the rail motor 244. Rail motor installation holes are formed in the upper parts of the rear slider cover plate 243 and the rail slider 241. The housing of the rail motor 244 is installed in the rail motor installation holes.

[0075] With such a setting, by using an integral rack and guide rail processing part, the matching precision between the guide rail and the roller is increased, the problem of guide rail clearance caused by assembly error is eliminated, and the overall stiffness problem is also solved.

[0076] The fixing method of the slider is that the upper V-shaped bearing cooperates with the inverted V-shaped track on the annular rack. There are a total of three rollers to realize the guiding function of the front and rear limit for circular track movement. On the lower side, the external V-shaped rollers on both sides are clamped with each other. On the one hand, it is convenient for installation, and on the other hand, it also provides an adjustment method for the clearance adjustment during assembly. A total of six rollers cooperate with each other to firmly fix the slider on the annular gear. The force conduction of the front 2-dof puncture needle is transmitted from the ceramic bearing and the bearing cover plate to the slider, and then from the slider to the annular rack. The two motor shafts at this part are not affected by the shear force generated by the offset, which well protects the motor and makes the operation more stable. The other compositions and connection relationships are the same as those in the first, second, third, fourth, fifth, sixth, or seventh specific embodiments.

[0077] Specific Embodiment Nine: In combination with Figures 1 to 16 This embodiment will be described. The base roll rotating assembly 25 of this embodiment includes a base roll motor 251, a base roll driving spur gear 252, a base roll driven spur gear 253, a base roll rotating shaft 254, and a base roll bearing cover 255. A base roll shaft hole is provided in the middle of the slider front cover 242. The base roll bearing cover 255 is installed on the front surface of the slider front cover 242. The shaft hole of the slider front cover 242 and the base roll shaft hole are coaxially arranged. The base roll rotating shaft 254 is installed in the shaft hole of the slider front cover 242 through a ceramic bearing. The end of the base roll rotating shaft 254 is connected to the rotating shaft of the base roll driven spur gear 253. The base roll driven spur gear 253 meshes with the base roll driving spur gear 252. The rotating shaft of the base roll driving spur gear 252 is connected to the rotating shaft of the base roll motor 251. Base roll motor mounting holes are provided in the upper parts of the slider rear cover 243 and the track slider 241. The housing of the base roll motor 251 is installed in the base roll motor mounting holes.

[0078] With such a setting, the rotation center of the puncture needle base coincides with the physical central axis of the entire slider after being reduced by a first-stage spur gear with a ratio of 1:2, which optimizes the force-bearing condition of the connection of the puncture needle. The force on the cantilever beam is transmitted to the rack through the bearing and the main shaft, without worrying about the deformation of the guide rail caused by the force on the cantilever beam. The installation can also be as simple as that of the guide rail slider, and the installation difficulty and maintenance cost are greatly reduced. The other components and connection relationships are the same as those in Specific Embodiments One, Two, Three, Four, Five, Six, Seven, or Eight.

[0079] The 1:2 reduction gear here not only plays the role of reducing speed and increasing torque, but also transfers the rotation center of the rotation degree of freedom of the puncture needle base roll to the geometric center of the slider through this set of reduction gears. This not only improves the force-bearing condition of the slider better than before, but also the movement range of the slider is a symmetric fan-shaped range, which provides great convenience for subsequent kinematic calculations. So far, problems such as the torque problem of the pitch axis, the machining and assembly accuracy problems of the guide rail when moving along the track, and the positioning and installation problems of the slider have all been solved.

[0080] Specific Embodiment Ten: In combination with Figures 1 to 16To describe this embodiment, the 2DOF puncture needle of this embodiment includes a puncture needle 31, a puncture needle lifting mechanism 32, and a puncture needle rotating mechanism 33. The puncture needle lifting mechanism 32 includes a puncture needle lifting bracket 321, a puncture needle lead screw nut mechanism 322, a puncture needle linear guide 323, and a puncture needle lifting motor 324. The puncture needle lifting bracket 321 is arranged vertically. A base roll rotating shaft hole is provided in the middle of the puncture needle lifting bracket 321. A vertically arranged puncture needle lead screw nut mechanism 322 is installed on the front surface of the puncture needle lifting bracket 321. The lower end of the lead screw of the puncture needle lead screw nut mechanism 322 is connected to the rotating shaft of the puncture needle lifting motor 324. The housing of the puncture needle lifting motor 324 is installed on the front surface of the puncture needle lifting bracket 321. A puncture needle linear guide 323 is provided on the side of the puncture needle lead screw nut mechanism 322. The lead screw nut of the puncture needle lead screw nut mechanism 322 is connected to the slider of the puncture needle linear guide 323;

[0081] The puncture needle rotating mechanism 33 includes a puncture needle rotating bracket 331, a puncture needle driving spur gear 332, a puncture needle driven spur gear 333, and a puncture needle rotating motor 334. The puncture needle rotating bracket 331 is horizontally arranged on the side of the needle lead screw nut mechanism 322. The puncture needle rotating bracket 331 is installed on the slider of the puncture needle lead screw nut mechanism 322. A puncture needle driving spur gear 332 is provided below the puncture needle rotating bracket 331. The rotating shaft of the puncture needle driving spur gear 332 passes through the puncture needle rotating bracket 331 and is connected to the rotating shaft of the puncture needle rotating motor 334. The housing of the puncture needle rotating motor 334 is installed on the upper surface of the puncture needle rotating bracket 331. A puncture needle driven spur gear 333 is provided on the side of the puncture needle driving spur gear 332. The puncture needle driven spur gear 333 meshes with the puncture needle driving spur gear 332. The rotating shaft of the puncture needle driven spur gear 333 is installed on the puncture needle rotating bracket 331 through a ceramic bearing. The rotating shaft of the puncture needle driven spur gear 333 is a hollow shaft. The upper part of the hollow shaft passes through the puncture needle rotating bracket 331 and the outer surface of the extended part is processed with external threads. The puncture needle 31 includes a puncture needle body and a puncture needle locking nut. The puncture needle body is inserted into the inner hole of the hollow shaft from top to bottom. The puncture needle locking nut is sleeved on the upper part of the puncture needle body. The puncture needle body is fixedly connected to the upper part of the hollow shaft through the puncture needle locking nut.

[0082] With such settings, for the structural design of the 2DOF puncture needle mechanism 33, this part needs to control the puncture needle to meet the design requirements of two degrees of freedom for feeding and rotation. The size should be as small as possible. The stroke of the feeding movement is 80 to 100 mm, and the rotation requires 360° free rotation. In addition, it also needs to meet the two usage requirements of quick replacement and positioning of the puncture needle, because the surgical puncture needle needs to be disinfected and cannot be reused. To meet these requirements, the 2DOF puncture needle adopts modular design during design. Each module has a complete function and is fixed to each other by bolt threads for convenient replacement and installation. The lifting mechanism realizes the lifting of the platform by the cooperation of a lead screw and a nut with a worm and a worm gear. The rotation of the needle is implemented by a set of spur gears with a transmission ratio of 1:1. The other components and connection relationships are the same as those in the first, second, third, fourth, fifth, sixth, seventh, eighth, or ninth specific implementation manners.

[0083] In this embodiment, the 2DOF puncture needle structure is designed to determine the position of the puncture needle and allow it to rotate freely by using ceramic bearings and thrust ball bearings. The force on the main shaft is transmitted to the base through the bearing group, and then transmitted from the base to the lead screw nut. The linear guide on the outside also plays a role in guiding and limiting, which makes neither of the two transmission gears subject to too large a deflection torque. The positions of the gears are fixed, and the movement of the mechanism will be more stable and safe. Among them, the linear guide is also processed with peek material, and the rollers are made by the interference fit of ceramic bearings and resin-printed shells.

[0084] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An MRI-compatible cranial nerve puncture robot, characterized in that: It includes a 2-DOF mobile chassis (1), a 3-DOF RCM mechanism (2), and a 2-DOF puncture needle (3). The 2-DOF mobile chassis (1) includes a mounting base plate (11) and two mobile platforms (12). On the upper surface of the mounting base plate (11), two mobile platforms (12) arranged side by side are respectively installed on the left and right sides. The 3-DOF RCM mechanism (2) includes a Pitch-axis driven rotary assembly (21), a Pitch-axis driving rotary assembly (22), a semi-circular rack (23), an arc-track moving assembly (24), and a base roll rotary assembly (25). Above the 2-DOF mobile chassis (1), there is a semi-circular rack (23). The two ends of the semi-circular rack (23) are respectively connected to the upper parts of the Pitch-axis driven rotary assembly (21) and the Pitch-axis driving rotary assembly (22). The lower parts of the Pitch-axis driven rotary assembly (21) and the Pitch-axis driving rotary assembly (22) are respectively connected to the two mobile platforms (12). In the middle of the semi-circular rack (23), there is an arc-track moving assembly (24) installed. On the arc-track moving assembly (24), there is a base roll rotary assembly (25) installed. The 2-DOF puncture needle (3) is installed on the base roll rotary assembly (25); Each mobile platform (12) includes a mobile-platform lead screw-nut mechanism (121), a mobile-platform linear guide mechanism (122), and a lifting link mechanism (123). The lifting link mechanism (123) includes a lifting platform (1231), a first lifting link (1232), a second lifting link (1233), a first link bearing seat (1234), and a second link bearing seat (1235); The Pitch-axis driving rotary assembly (22) includes a Pitch-axis worm-and-wheel mechanism, a right Pitch-axis (221), an upper right-side support plate (222), two right Pitch-axis supports (223), and two right-side support side plates (224). The right Pitch-axis support (223) is an L-shaped shaft support. The two right Pitch-axis supports (223) are vertically and symmetrically installed on the upper surface of the right-side lifting platform (1231). The two ends of the right Pitch-axis (221) are respectively installed in the shaft holes of the two right Pitch-axis supports (223) through two ceramic bearings. The two right-side support side plates (224) are respectively arranged vertically and oppositely on the outer sides of the upper parts of the two right Pitch-axis supports (223). The two right-side support side plates (224) are respectively fixedly connected to the two ends of the right Pitch-axis (221). Above the two right-side support side plates (224), there is an upper right-side support plate (222). The two sides of the bottom of the upper right-side support plate (222) are respectively connected to the tops of the two right-side support side plates (224). The top of the upper right-side support plate (222) is connected to the lower right end of the semi-circular rack (23); The Pitch axis worm and gear mechanism includes a Pitch axis worm gear (225), a Pitch axis worm (226), a Pitch axis worm and gear motor (227), a Pitch axis worm and gear motor support (228) and a Pitch axis worm bearing block (229). The Pitch axis worm gear (225) is installed in the middle of the right Pitch axis (221). An inclined Pitch axis worm (226) is provided on the side of the Pitch axis worm gear (225). The end shaft section of the Pitch axis worm (226) is connected to the Pitch axis worm bearing block (229) through a ceramic bearing. The Pitch axis worm bearing block (229) is installed on the upper surface of the lifting platform (1231). The lower part of the Pitch axis worm (226) meshes with the Pitch axis worm gear (225). The head shaft section of the Pitch axis worm (226) is connected to the rotating shaft of the Pitch axis worm and gear motor (227). The Pitch axis worm and gear motor (227) is installed on the Pitch axis worm and gear motor support (228). The Pitch axis worm and gear motor support (228) is installed on the upper surface of the lifting platform (1231).

2. The MRI-compatible cranial nerve puncture robot according to claim 1, characterized in that: The moving platform lead screw and nut mechanism (121) and the moving platform linear guide mechanism (122) are arranged side by side in sequence from outside to inside on the mounting base plate (11). The lifting platform (1231) is located above the moving platform (12). One end of the first lifting connecting rod (1232) is rotatably connected to one end of the lifting platform (1231) through a connecting piece. The other end of the first lifting connecting rod (1232) is rotatably connected to the first connecting rod bearing block (1234) through a connecting piece. The first connecting rod bearing block (1234) is installed on the upper surface of the slider of the moving platform linear guide mechanism (122). One end of the second lifting connecting rod (1233) is rotatably connected to the other end of the lifting platform (1231) through a connecting piece. The other end of the second lifting connecting rod (1233) is rotatably connected to the second connecting rod bearing block (1235) through a connecting piece. The second connecting rod bearing block (1235) is installed on the upper surface of the lead screw nut of the moving platform lead screw and nut mechanism (121).

3. The MRI-compatible cranial nerve puncture robot according to claim 1 or 2, characterized in that: The first lifting connecting rod (1232) and the second lifting connecting rod (1233) have the same structure. The first lifting connecting rod (1232) includes two lifting connecting rod bodies (12321), two connecting rod pin shafts (12322) and three connecting rod connecting blocks (12323). The two lifting connecting rod bodies (12321) are arranged side by side. The middle parts of the two lifting connecting rod bodies (12321) are connected by three connecting rod connecting blocks (12323) arranged at equal intervals. One end of the two lifting connecting rod bodies (12321) is rotatably connected to the lifting platform (1231) through a connecting rod pin shaft (12322). The other end of the two lifting connecting rod bodies (12321) is connected to the first connecting rod bearing block (1234) or the second connecting rod bearing block (1235) through a ceramic bearing.

4. The MRI-compatible cranial nerve puncture robot according to claim 3, wherein: The lead screw nut mechanism (121) of the moving platform includes a moving platform lead screw motor (1211), a moving platform lead screw (1212), a moving platform lead screw nut (1213), and two moving platform lead screw bearing seats (1214). The moving platform lead screw (1212) is horizontally arranged above the mounting base plate (11). Both ends of the moving platform lead screw (1212) are respectively connected to the mounting base plate (11) through two moving platform lead screw bearing seats (1214). One end of the moving platform lead screw (1212) is connected to the moving platform lead screw motor (1211). The moving platform lead screw motor (1211) is installed on the upper surface of the mounting base plate (11). The moving platform lead screw nut (1213) is threadedly connected to the moving platform lead screw (1212).

5. The MRI-compatible cranial nerve puncture robot according to claim 4, wherein: The linear guide mechanism (122) of the moving platform includes a moving platform linear guide body (1221), a three-hole slider (1222), two guide rail stoppers (1223), and three moving platform rollers (1224). The cross-section of the moving platform linear guide body (1221) is U-shaped. On the upper parts of the two inner side surfaces of the chute of the moving platform linear guide body (1221), there are two guiding protrusions arranged side by side along the length direction of the guide rail. Two guide rail stoppers (1223) are respectively installed at both ends of the chute of the moving platform linear guide body (1221). The three-hole slider (1222) is horizontally arranged above the moving platform linear guide body (1221). Below the three-hole slider (1222), three moving platform rollers (1224) are arranged at equal intervals from front to back along the length direction of the slider. Three roller pins are respectively inserted into the three inner holes of the three-hole slider (1222). The lower ends of the three roller pins are respectively connected to the three moving platform rollers (1224) through three ceramic bearings.

6. The MRI-compatible cranial nerve puncture robot according to claim 5, characterized in that: The driven rotary assembly (21) of the Pitch axis includes a left Pitch axis (211), a left Pitch axis support (212), an upper plate of the left support (213), and two left support side plates (214). The left Pitch axis support (212) is an inverted T-shaped support. The left Pitch axis support (212) is installed on the upper surface of the left lifting platform (1231). The middle part of the left Pitch axis (211) is installed in the shaft hole of the left Pitch axis support (212) through a ceramic bearing. The two left support side plates (214) are respectively arranged vertically and oppositely on both sides of the upper part of the left Pitch axis support (212). The two left support side plates (214) are respectively fixedly connected to both ends of the left Pitch axis (211). An upper plate of the left support (213) is arranged above the two left support side plates (214). Both sides of the bottom of the upper plate of the left support (213) are respectively connected to the tops of the two left support side plates (214). The top of the upper plate of the left support (213) is connected to the lower left end of the semi-circular rack (23).

7. The MRI-compatible cranial nerve puncture robot according to claim 6, wherein: The arc-shaped track moving assembly (24) includes a track slider (241), a front slider cover plate (242), a rear slider cover plate (243), a track motor (244), a backlash eliminator gear (245), two upper guide wheels (246), two sets of lower guide wheels (247) and a plurality of cover plate connection blocks (248). The front slider cover plate (242) and the rear slider cover plate (243) are both arc-shaped plate structures. The front slider cover plate (242) and the rear slider cover plate (243) are vertically symmetrically arranged. A plurality of cover plate connection blocks (248) are respectively arranged on the upper and lower sides of the inner surfaces of the front slider cover plate (242) and the rear slider cover plate (243). The cover plate connection blocks (248) are connected to the front slider cover plate (242) and the rear slider cover plate (243) through connecting elements. The track slider (241) is installed on the upper part of the inner surface of the front slider cover plate (242) and the rear slider cover plate (243). The cross-section of the track slider (241) is an L-shaped block structure. Two upper guide wheels (246) are uniformly arranged along the length direction on the rear side of the vertical section at the bottom of the track slider (241). An annular upper wheel groove is formed on the side surface of the upper guide wheel (246). The semi-circular rack (23) is arranged below the track slider (241). An arc-shaped protrusion matching the annular upper wheel groove is arranged along the length direction of the rear side of the upper part of the semi-circular rack (23). Two pairs of coaxially arranged lower guide wheels (247) are respectively arranged on the front and rear sides of the bottom of the track slider (241). The two rollers in each set of lower guide wheels (247) are respectively rotatably connected to the front slider cover plate (242) and the rear slider cover plate (243). Arc-shaped guide grooves matching the two rollers in each set of lower guide wheels (247) are respectively arranged on the front and rear sides of the bottom of the track slider (241). An annular rack body is arranged along the length direction of the front side of the upper part of the semi-circular rack (23). A backlash eliminator gear (245) meshing with the rack body is arranged above the annular rack body. The backlash eliminator gear (245) is installed on the rotating shaft of the track motor (244). Track motor installation holes are formed in the upper parts of the rear slider cover plate (243) and the track slider (241). The housing of the track motor (244) is installed in the track motor installation holes.

8. The MRI-compatible cranial nerve puncture robot according to claim 7, characterized in that: The base roll rotation assembly (25) includes a base roll motor (251), a base roll driving spur gear (252), a base roll driven spur gear (253), a base roll rotating shaft (254), and a base roll bearing cover plate (255). A base roll shaft hole is provided in the middle of the slider front cover plate (242). The base roll bearing cover plate (255) is installed on the front surface of the slider front cover plate (242). The shaft hole of the slider front cover plate (242) and the base roll shaft hole are coaxially arranged. The base roll rotating shaft (254) is installed in the shaft hole of the slider front cover plate (242) through a ceramic bearing. The end of the base roll rotating shaft (254) is connected to the rotating shaft of the base roll driven spur gear (253). The base roll driven spur gear (253) meshes with the base roll driving spur gear (252). The rotating shaft of the base roll driving spur gear (252) is connected to the rotating shaft of the base roll motor (251). Base roll motor mounting holes are provided in the upper parts of the slider rear cover plate (243) and the track slider (241). The housing of the base roll motor (251) is installed in the base roll motor mounting holes.

9. The MRI-compatible cranial nerve puncture robot according to claim 8, wherein: The 2DOF puncture needle includes a puncture needle (31), a puncture needle lifting mechanism (32), and a puncture needle rotating mechanism (33). The puncture needle lifting mechanism (32) includes a puncture needle lifting bracket (321), a puncture needle lead screw nut mechanism (322), a puncture needle linear guide (323), and a puncture needle lifting motor (324). The puncture needle lifting bracket (321) is vertically arranged. A base roll rotating shaft hole is provided in the middle of the puncture needle lifting bracket (321). A vertically arranged puncture needle lead screw nut mechanism (322) is installed on the front surface of the puncture needle lifting bracket (321). The lower end of the lead screw of the puncture needle lead screw nut mechanism (322) is connected to the rotating shaft of the puncture needle lifting motor (324). The housing of the puncture needle lifting motor (324) is installed on the front surface of the puncture needle lifting bracket (321). A puncture needle linear guide (323) is provided on the side of the puncture needle lead screw nut mechanism (322). The lead screw nut of the puncture needle lead screw nut mechanism (322) is connected to the slider of the puncture needle linear guide (323); The puncture needle rotating mechanism (33) includes a puncture needle rotating bracket (331), a puncture needle driving cylindrical gear (332), a puncture needle driven cylindrical gear (333), and a puncture needle rotating motor (334). The puncture needle rotating bracket (331) is horizontally arranged on the side of the puncture needle lead screw nut mechanism (322). The puncture needle rotating bracket (331) is installed on the slider of the puncture needle lead screw nut mechanism (322). A puncture needle driving cylindrical gear (332) is provided below the puncture needle rotating bracket (331). The rotating shaft of the puncture needle driving cylindrical gear (332) passes through the puncture needle rotating bracket (331) and is connected to the rotating shaft of the puncture needle rotating motor (334). The housing of the puncture needle rotating motor (334) is installed on the upper surface of the puncture needle rotating bracket (331). A puncture needle driven cylindrical gear (333) is provided on the side of the puncture needle driving cylindrical gear (332). The puncture needle driven cylindrical gear (333) meshes with the puncture needle driving cylindrical gear (332). The rotating shaft of the puncture needle driven cylindrical gear (333) is installed on the puncture needle rotating bracket (331) through a ceramic bearing. The rotating shaft of the puncture needle driven cylindrical gear (333) is a hollow shaft. The upper part of the hollow shaft passes through the puncture needle rotating bracket (331) and the outer surface of the protruding part is processed with an external thread. The puncture needle (31) includes a puncture needle body and a puncture needle locking nut. The puncture needle body is inserted into the inner hole of the hollow shaft from top to bottom. The puncture needle locking nut is sleeved on the upper part of the puncture needle body. The puncture needle body is fixedly connected to the upper part of the hollow shaft through the puncture needle locking nut.

Images