A multi-degree of freedom minimally invasive surgical end effector

Abstract

The application provides a multi-degree-of-freedom minimally invasive surgery end effector, which comprises a base, a driving assembly and a transmission assembly, the driving assembly comprises a first driving component, a second driving component and a third driving component which are fixed on the base, and the transmission assembly comprises a first transmission component, a second transmission component and an execution component, the first transmission component is rotatably connected with the first driving component around a first axis, and the first driving component is used to drive the first transmission component to rotate around a second axis, the second transmission component has a first state and a second state, in the first state, the driving assembly is used to drive the second end of the execution component to rotate around the first axis through the second transmission component, in the second state, the driving assembly is used to drive the execution component to be movable in a first direction through the second transmission component, and the first direction has an included angle with the plane where the first axis and the second axis are located. The multi-degree-of-freedom minimally invasive surgery end effector has the advantages of compact structure and strong flexibility.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, specifically, it relates to a multi-degree-of-freedom minimally invasive surgical end effector. Background Technology

[0002] Minimally invasive surgical robots mainly consist of a console system, a manipulator system, and an imaging system. The end effector of the manipulator system typically includes an RCM (Remote Control Mechanism) and surgical instruments mounted on the RCM. The RCM, utilizing its distal stationary point, allows for greater freedom of manipulation of the lesion site. With the assistance of the surgeon and the imaging system, the end effector's posture can be adjusted to ultimately enable the surgical robot to perform its surgical procedures.

[0003] In related technologies, the design of the end effector in minimally invasive surgery has limited freedom, making it difficult to achieve multi-angle, high-precision operation in a confined space; some mechanisms are relatively large, increasing the potential risk of damage to patient tissues; and some designs need improvement in terms of flexibility, force feedback, and maneuverability, making it difficult to fully meet the needs of complex surgical scenarios. Summary of the Invention

[0004] The present invention aims to at least partially solve one of the technical problems in the related art.

[0005] Therefore, embodiments of the present invention propose a multi-degree-of-freedom minimally invasive surgical end effector. The multi-degree-of-freedom minimally invasive surgical end effector has a compact structure and high flexibility, meeting the needs of complex minimally invasive surgical scenarios for multi-angle, high-precision, and low-damage control of the end effector.

[0006] The multi-degree-of-freedom minimally invasive surgical end effector of this invention includes:

[0007] Base; A drive assembly, the drive assembly comprising a first drive component, a second drive component, and a third drive component fixedly disposed on the base; A transmission assembly includes a first transmission component, a second transmission component, and an actuating component. The first transmission component is rotatably connected to a first driving component about a first axial direction, and the first driving component drives the first transmission component to rotate about a second axial direction. The second axial direction is parallel to the axial direction of the output shaft of the first driving component, and the first axial direction is orthogonal to the second axial direction. The second transmission component is connected to the second drive component and the third drive component. The first end of the execution component is connected to the first transmission component and the second transmission component through a connecting component. The second transmission component has a first state and a second state. In the first state, the drive component is used to drive the second end of the execution component to rotate about a first axis through the second transmission component. In the second state, the drive component is used to drive the execution component to move along a first direction through the second transmission component. The first direction has an angle between it and the plane containing the first axis and the second axis.

[0008] The multi-degree-of-freedom minimally invasive surgical end effector of this invention achieves multi-degree-of-freedom composite motion by converging a first transmission component and a second transmission component at the first end of the execution component, using the fewest intermediate components. The design of the first direction forming an angle with the plane containing the two axes further extends the motion of the execution component from a plane to three-dimensional space, adapting to complex surgical paths. Its compact structure and high flexibility meet the needs of complex minimally invasive surgical scenarios for multi-angle, high-precision, and low-damage control of the end effector.

[0009] In some embodiments, the first transmission component includes a first connecting rod, a second connecting rod, and a third connecting rod; the connecting component includes a first crossbar; there are two first connecting rods and two second connecting rods, each spaced apart along a second axial direction; a first end of the first connecting rod is rotatably connected to the third connecting rod; and a second end of the first connecting rod is rotatably connected to the base and the output shaft of the first driving component, respectively; the lines connecting the second ends of the first connecting rod, the third connecting rod, and the second connecting rod form a parallelogram structure. The first end of the second link is rotatably connected to the third link, and the second end of each of the second links is rotatably connected to the first end of the first crossbar. The second link, the third link, and the first end of the first crossbar form a parallelogram structure.

[0010] In some embodiments, the transmission assembly further includes a bearing housing disposed on the base, the bearing housing and the first drive component being spaced apart along the second axis, a second end of a first connecting rod being rotatably connected to the bearing housing, and the axis of the bearing housing being parallel to the second axis.

[0011] In some embodiments, the first connecting rod includes a straight rod and a curved rod connected together, the straight rod and the curved rod being generally L-shaped, the straight rod being connected to the third connecting rod, and the curved rod being connected to the bearing housing and the output shaft of the first drive component, respectively.

[0012] In some embodiments, the connecting component further includes a second crossbar, the two ends of which are rotatably connected to the second transmission component and the actuation component, respectively, and the second end of the first crossbar, the first end of the actuation component, the second crossbar, and a portion of the second transmission component form a parallelogram structure.

[0013] In some embodiments, the second crossbar is located on the side of the first crossbar away from the base.

[0014] In some embodiments, the second transmission component includes a differential gear set and an output component. The differential gear set includes a first input shaft and a second input shaft, which are respectively connected to the output shaft of the second drive component and the output shaft of the third drive component. The output component includes an output rotating component and an output moving component. The output rotating component meshes with the differential gear set via gears. The output moving component is sleeved on the output rotating component. The first crossbar and the second crossbar are rotatably connected to the output moving component. The output rotating component rotates to drive the output moving component to move along the first direction.

[0015] In some embodiments, the transmission method of the output component includes one of the following: lead screw and nut helical transmission, ball spline helical transmission, helical groove pin transmission, and differential thread transmission.

[0016] In some embodiments, the differential gear set further includes an auxiliary connecting rod, a first bevel gear set, a second bevel gear set, a third bevel gear set, a fourth bevel gear, and a transmission bevel gear. The first bevel gear set is connected to the first input shaft, the second bevel gear set is rotatably connected to the first input shaft via the auxiliary connecting rod, the second bevel gear set is rotatably connected to the second input shaft via the auxiliary connecting rod, and the fourth bevel gear is connected to the second output shaft. The first bevel gear set includes a first driving gear and a first driven gear; the second bevel gear set includes a second driving gear and a second driven gear; and the third bevel gear set includes a third driving gear and a third driven gear. The first driving gear meshes with the third driving gear, the first driven gear meshes with the second driving gear, the second driving gear meshes with the fourth bevel gear, the output rotating component is connected to the transmission bevel gear, and the second driven gear and the third driven gear mesh with the transmission bevel gear.

[0017] In some embodiments, the first driving gear and the third driving gear are the same gear, the first driven gear, the second driving gear and the fourth bevel gear are the same gear, and the second driven gear, the third driven gear and the transmission bevel gear are the same gear. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the multi-degree-of-freedom minimally invasive surgical end effector according to an embodiment of the present invention.

[0019] Figure 2 This is a schematic diagram of the structure of the first link of the multi-degree-of-freedom minimally invasive surgical end effector according to an embodiment of the present invention.

[0020] Figure 3 This is a three-dimensional structural schematic diagram of the differential gear assembly of the multi-degree-of-freedom minimally invasive surgical end effector according to an embodiment of the present invention.

[0021] Figure 4 This is a schematic diagram of the differential gear set of the multi-degree-of-freedom minimally invasive surgical end effector according to an embodiment of the present invention.

[0022] Figure label: 1. Base 21. First drive component; 22. Second drive component; 23. Third drive component. 31. First transmission component; 311. First connecting rod; 3111. Straight rod; 3112. Crank rod; 312. Second connecting rod; 313. Third connecting rod. 32. Second transmission component; 321. First input shaft; 322. Second input shaft; 323. Auxiliary connecting rod. 3241. First driving gear; 3242. First driven gear. 3251. Second driving gear; 3252. Second driven gear. 3261. Third driving gear; 3262. Third driven gear. 327. Fourth bevel gear, 328. Transmission bevel gear, 331. Output rotating component; 332. Output moving component. 34. Actuating components, 35. Connecting component; 351. First crossbar; 352. Second crossbar. 36. Bearing housing. Detailed Implementation

[0023] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0024] like Figures 1-4 As shown, the multi-degree-of-freedom minimally invasive surgical end effector of this invention includes: a base 1, a drive assembly, and a transmission assembly.

[0025] The drive assembly includes a first drive component 21, a second drive component 22, and a third drive component 23 fixedly mounted on the base 1. The transmission assembly includes a first transmission component 31, a second transmission component 32, and an actuation component 34. The first transmission component 31 is rotatably connected to the first drive component 21 about a first axis, and the first drive component 21 drives the first transmission component 31 to rotate about a second axis. The second axis is parallel to the axis of the output shaft of the first drive component 21, and the first axis is orthogonal to the second axis. The second transmission component 32 is connected to the second drive component 22 and the third drive component 23. The first end of the actuation component 34 is connected to the first transmission component 31 and the second transmission component 32 through a connecting component 35. The second transmission component 32 has a first state and a second state. In the first state, the drive assembly drives the second end of the actuation component 34 to rotate about the first axis through the second transmission component 32. In the second state, the drive assembly drives the actuation component 34 to move along a first direction through the second transmission component 32. The first direction has an angle with the plane containing the first axis and the second axis.

[0026] Specifically, such as Figures 1-4 As shown, the first driving component 21, the second driving component 22, and the third driving component 23 are all fixedly mounted on the base 1, and the axial direction of the output shafts of the three driving components is in the same direction (i.e., parallel to the second axial direction).

[0027] The first transmission component 31 has a rotating pair (such as a hinge or bearing structure) with the first axis of rotation as the axis of rotation. One end of the rotating pair is connected to the first drive component 21 (or a structure fixed to the first drive component 21), so that the first transmission component 31 can rotate freely about the first axis relative to the first drive component 21.

[0028] The first driving component 21 is used to drive the first transmission component 31 to rotate around a second axis. The second axis is parallel to the axis of the output shaft of the first driving component 21. This means the direction of the output shaft of the first driving component 21 is the direction of the second axis. The output shaft of the first driving component 21 can transmit power to the first transmission component 31 through a transmission method such as gears, connecting rods, or worm gears, driving it to rotate actively around the second axis.

[0029] like Figures 1-4As shown, the second transmission component 32 is connected to both the second drive component 22 and the third drive component 23. That is, the output power of the two drive components acts together on the second transmission component 32, which is the point where their power converges. This connection provides the power source for the second transmission component 32 to achieve two different operating states.

[0030] The first end of the actuating component 34 is connected to both the first transmission component 31 and the second transmission component 32 via a connecting component 35 (such as a connecting rod, universal joint, or other intermediate component). That is, the movements of both the first transmission component 31 and the second transmission component 32 are transmitted to the first end of the actuating component 34 through the connecting component 35, and the movement of the actuating component 34 is the result of the combined action of both. The second end of the actuating component 34 is a free end (i.e., the surgical operating end), and its movement is determined by the movement state of the first end.

[0031] In the first state (rotation mode): In this state, the second drive component 22 and the third drive component 23 drive the second end of the actuator 34 to rotate around the first axis via the second transmission component 32. That is, after the power is transmitted through the second transmission component 32, the distal end of the actuator 34 swings around the first axis.

[0032] In the second state (movement mode): In this state, the second drive component 22 and the third drive component 23 drive the execution component 34 to move along the first direction via the second transmission component 32. The first direction has an angle with the plane containing the first and second axes, meaning the first direction is not parallel to the plane and has an inclination angle (possibly along the length of the execution component 34 or other spatial directions).

[0033] It should be noted that, as Figures 1-4 As shown, the plane containing the first axis and the second axis is a horizontal plane, and the first direction is the extension direction of the parallel execution component 34, that is, the first direction has a certain angle with the horizontal plane, so that the execution component 34 can perform corresponding operations in different states.

[0034] In other words, under the driving action of the drive component, the execution component 34 can rotate around the first axis, rotate around the second axis, and move along the first direction. Furthermore, under the combined action of different drive components of the drive component, it can rotate or move simultaneously, so as to achieve more complex angle adjustments and be suitable for more operating scenarios.

[0035] In other words, the multi-degree-of-freedom minimally invasive surgical end effector of this invention, through the convergence of the first transmission component 31 and the second transmission component 32 to the first end of the execution component 34, achieves multi-degree-of-freedom composite motion with the fewest intermediate components; the design of the first direction forming an angle with the plane containing the two axes further extends the motion of the execution component 34 from a plane to three-dimensional space, adapting to complex surgical paths. Its compact structure and high flexibility meet the needs of complex minimally invasive surgical scenarios for multi-angle, high-precision, and low-damage control of the end effector.

[0036] In some embodiments, the first transmission component 31 includes a first connecting rod 311, a second connecting rod 312, and a third connecting rod 313, and the connecting component 35 includes a first crossbar 351. There are two first connecting rods 311 and two second connecting rods 312. The two first connecting rods 311 and the two second connecting rods 312 are arranged at intervals along the second axis. The first end of the first connecting rod 311 is rotatably connected to the third connecting rod 313. The second end of the first connecting rod 311 is rotatably connected to the output shaft of the base 1 and the first driving component 21, respectively. The line connecting the second ends of the first connecting rod 311, the third connecting rod 313, and the second connecting rod 312 forms a parallelogram structure. The first end of the second connecting rod 312 is rotatably connected to the third connecting rod 313. The second ends of the second connecting rod 312 are rotatably connected to the first end of the first crossbar 351. The first ends of the second connecting rod 312, the third connecting rod 313, and the first crossbar 351 form a parallelogram structure.

[0037] Specifically, such as Figures 1-4 As shown, two first connecting rods 311 are arranged at intervals along the second axis (i.e., symmetrically arranged and parallel); the first end (upper end) of each first connecting rod 311 is rotatably connected to the third connecting rod 313; the second end (lower end) of each first connecting rod 311 is rotatably connected to the output shaft of the base 1 and the first drive component 21, respectively. The two first connecting rods 311 (as left and right sides), the third connecting rod 313 (as top side), and the line connecting the two connection points on the base 1 (as bottom side) together form a parallelogram.

[0038] Two second links 312 are arranged at intervals along a second axis; the first end of each second link 312 is rotatably connected to a third link 313; the second end of each second link 312 is rotatably connected to the first end of a first crossbar 351. The two second links 312 (left and right sides), the third link 313 (bottom side), and the first crossbar 351 (top side) together form a second parallelogram.

[0039] Understandably, during use, after being transmitted through the double parallelogram series, the first crossbar 351 always remains parallel to the base 1. That is, during the swinging process, the attitude (relative to the base 1) of the actuator 34 does not change, achieving pure translational swinging. For surgical operations, the instrument tip maintains a stable orientation when changing position, eliminating the need for frequent adjustments to the instrument angle, making the operation more intuitive and stable.

[0040] In other words, by connecting two parallelograms in series, the minute driving angle at the base 1 end can be gradually amplified into a larger displacement at the distal end of the actuator 34, while maintaining precise control of the motion trajectory. In minimally invasive surgery, the surgeon's actions at the base 1 end can be precisely mapped to the actuator end, and the motion ratio is adjustable, achieving the effect of amplifying fine operations—that is, the surgeon's large-amplitude operations are converted into fine, small-amplitude movements at the actuator end, improving surgical precision; or the small-amplitude movements at the base 1 end are amplified by the connecting rod and drive the actuator end to achieve a larger swing angle range, expanding the operating space.

[0041] In some embodiments, the transmission assembly further includes a bearing housing 36, which is disposed on the base 1. The bearing housing 36 and the first drive component 21 are spaced apart in the second axis. The second end of a first connecting rod 311 is rotatably connected to the bearing housing 36, and the axis of the bearing housing 36 is parallel to the second axis.

[0042] Specifically, such as Figures 1-4 As shown, the bearing housing 36 and the first drive component 21 are arranged at a distance along the second axis, that is, the two are staggered by a certain distance along the direction parallel to the output shaft of the first drive component 21 (the second axis); the axis of the bearing housing 36 itself (that is, the direction of its rotation center line) is parallel to the second axis.

[0043] Two first links 311 are arranged at intervals along the second axis. The second end of one of the first links 311 (not both) is rotatably connected to the bearing housing 36. The second end of the other first link 311 is rotatably connected to the output shaft of the first drive component 21 as described above.

[0044] In other words, the first parallelogram (the parallelogram formed by the first link 311 and the third link 313) requires two bottom hinge points (two fixed rotation points on the base 1) to realize the four-bar linkage movement of the parallelogram. If the second ends of both first links 311 are directly connected to the output shaft of the first drive component 21, the output shaft needs to withstand a large radial load and off-center torque.

[0045] By setting an independent bearing housing 36, the fulcrum of one of the first connecting rods 311 is separated from the output shaft of the drive component, achieving independent setting of the two fulcrums. This allows each of the two hinge points on the bottom edge to have an independent support structure, making the geometric constraints of the parallelogram mechanism more stable. The output shaft of the drive component no longer needs to bear the radial force of both connecting rods simultaneously, reducing the load on the output shaft, which helps extend the service life of the drive component and reduce wear, while also improving the accuracy and stability of the transmission.

[0046] In some embodiments, the first link 311 includes a straight rod 3111 and a curved rod 3112 connected together. The straight rod 3111 and the curved rod 3112 are generally L-shaped. The straight rod 3111 is connected to the third link 313, and the curved rod 3112 is connected to the bearing seat 36 and the output shaft of the first drive component 21, respectively.

[0047] Specifically, such as Figures 1-4 As shown, the first connecting rod 311 is formed by connecting a straight rod 3111 and a curved rod 3112, which are roughly L-shaped. That is, the straight rod 3111 and the curved rod 3112 are at a certain angle (close to 90°), forming a turning structure.

[0048] One end (or end region) of the straight rod 3111 is connected to the third connecting rod 313. In conjunction with the aforementioned double parallelogram structure, this connection should be rotatable, with the straight rod 3111 serving as one side of the first parallelogram. The curved rod 3112 is connected to both the bearing housing 36 and the output shaft of the first drive component 21. The two first connecting rods 311 are arranged spaced apart along the second axis, with the curved rod 3112 of one first connecting rod 311 rotatably connected to the bearing housing 36, and the curved rod 3112 of the other first connecting rod 311 rotatably connected to the output shaft of the first drive component 21.

[0049] In other words, if the first link 311 is a straight link 3111, its pivot point (the connection point between the curved link 3112 and the base 1) is on the same straight line as the main body of the link. When the first link 311 swings, the straight link 3111 itself will interfere with the base 1 or the drive component, limiting the maximum swing angle. By using an L-shaped design, the pivot point is moved backward / laterally through the curved link 3112, making it spatially offset from the main body of the straight link 3111. In this way, when the straight link 3111 swings, the interference space between its motion trajectory and the base 1 and the drive component is significantly reduced, thus allowing a larger swing angle range. For minimally invasive surgery, a larger swing angle means that the actuator 34 can adjust its posture in a wider space, expanding the reach of the surgical operation.

[0050] In some embodiments, the connecting member 35 further includes a second crossbar 352, the two ends of which are rotatably connected to the second transmission member 32 and the actuation member 34, respectively. The second end of the first crossbar 351, the first end of the actuation member 34, the second crossbar 352, and a portion of the second transmission member 32 form a parallelogram structure.

[0051] Specifically, such as Figures 1-4 As shown, the two ends of the second crossbar 352 are rotatably connected to the second transmission component 32 and the actuation component 34, respectively. That is, one end of the second crossbar 352 is connected to the second transmission component 32, and the other end is connected to the actuation component 34, forming an intermediate force transmission component.

[0052] The second end of the first crossbar 351 serves as a vertex of the parallelogram; the first end (proximal end) of the actuating component 34 serves as the second vertex of the parallelogram; the second crossbar 352 serves as the top edge of the parallelogram, with its two ends connected to the second transmission component 32 and the actuating component 34 respectively; a specific part on the second transmission component 32 (such as a connection point or an extension arm) serves as the fourth vertex of the parallelogram.

[0053] Understandably, one end of the second crossbar 352 is connected to the second transmission component 32, and the other end is connected to the execution component 34. The movement of the second transmission component 32 (from the second and third drive components 23, rotating in state one and moving in state two) is transmitted to the execution component 34 through the second crossbar 352; the movement of the first transmission component 31 (transmitted through the first crossbar 351) also merges with the movement of the second crossbar 352 at the first end of the execution component 34 through the third-level parallelogram.

[0054] In other words, in this embodiment of the invention, each parallelogram of the multi-degree-of-freedom minimally invasive surgical end effector ensures that its output side remains parallel to its input side. After the three stages are connected in series, the attitude of the actuator 34 relative to the base 1 remains constant, regardless of how it swings in space.

[0055] In minimally invasive surgery, the posture stability of the surgical instrument's end effector (the second end of the actuator 34) is crucial—when the surgeon needs to move the instrument from one position to another, it is desirable that the instrument's orientation does not change with the position to avoid accidental cutting or damage to surrounding tissues. The three-level parallelogram series connection makes this posture maintenance function more reliable, the transmission distance longer, and the motion errors of each link will not accumulate and amplify, ensuring the positioning accuracy after long-distance transmission.

[0056] In some embodiments, the second crossbar 352 is located on the side of the first crossbar 351 away from the base 1.

[0057] It is understandable that, such as Figures 1-4As shown, the first horizontal bar 351 serves as the endpoint of the output of the first two levels of parallelograms, and its second end also serves as a vertex of the third level of parallelograms. The second horizontal bar 352 is located on the far side of the first horizontal bar 351, which means that the third level of parallelograms extends outward in a direction away from the base 1.

[0058] This serial arrangement ensures a unidirectional, progressive motion transmission path, with each stage building upon the previous one to the far end, resulting in a clear path and distinct layers. Within a limited space, this sequential arrangement avoids spatial intersections and overlaps of the rods, effectively reducing the risk of motion interference and guaranteeing the end effector's passability and motion reliability within the casing.

[0059] In some embodiments, the second transmission component 32 includes a differential gear set and an output component. The differential gear set includes a first input shaft 321 and a second input shaft 322. The first input shaft 321 and the second input shaft 322 are respectively connected to the output shaft of the second drive component 22 and the output shaft of the third drive component 23. The output component includes an output rotating component 331 and an output moving component 332. The output rotating component 331 meshes with the differential gear set through gears. The output moving component 332 is sleeved on the output rotating component 331. The first crossbar 351 and the second crossbar 352 are both rotatably connected to the output moving component 332. The output rotating component 331 rotates to drive the output moving component 332 to move along a first direction.

[0060] Specifically, such as Figures 1-4 As shown, the differential gear set includes a first input shaft 321 and a second input shaft 322. The first input shaft 321 is connected to the output shaft of the second drive component 22 and receives power input from the second drive component 22. The second input shaft 322 is connected to the output shaft of the third drive component 23 and receives power input from the third drive component 23. The two input shafts independently input power, and the motion is synthesized and distributed through the gear system (such as a planetary gear system or a bevel gear differential mechanism) inside the differential gear set.

[0061] The output rotating component 331 is connected to the differential gear set via gear meshing. That is, the output end of the differential gear set transmits motion to the output rotating component 331 through gear transmission, driving the output rotating component 331 to rotate. The output rotating component 331 is a rotating component directly driven by the differential gear set.

[0062] The output moving part 332 is fitted onto the output rotating part 331. This means that the output moving part 332 is fitted onto the outside (or inside) of the output rotating part 331, and there is a helical pair between the two (such as a lead screw-nut mechanism, ball screw pair, or sliding helical pair). When the output rotating part 331 rotates, the output moving part 332 moves linearly along the axial direction under the action of the helical pair.

[0063] The first crossbar 351 and the second crossbar 352 are both rotatably connected to the output moving member 332. That is, the output moving member 332 is provided with a hinge point, and the first crossbar 351 and the second crossbar 352 are respectively connected to different positions of the output moving member 332 through a revolute joint, so that the movement of the output moving member 332 is transmitted to the actuating component 34 through these two crossbars.

[0064] Understandably, two independent input shafts are connected to two drive components, and motion synthesis is achieved through a differential gear set. The core advantage of the differential gear set is that the two drive components can be driven collaboratively or controlled differentially. When the two drive components rotate in the same direction at the same speed, the differential output synthesizes a larger torque or speed; when the two drive components rotate in opposite directions or at different speeds, the differential output produces fine angle adjustments or motion mode switching.

[0065] In other words, the two motors can work simultaneously, providing greater output torque to ensure that the end effector has sufficient force to operate when it contacts the tissue; through differential fine-tuning, more precise angle or position control can be achieved than with single-motor drive, improving the accuracy of surgical operations.

[0066] In some embodiments, the transmission method of the output component includes one of the following: lead screw and nut helical transmission, ball spline helical transmission, helical groove pin transmission, and differential thread transmission. It is understood that different transmission methods are selected based on different emphases on indicators such as accuracy, efficiency, size, load, and cost depending on the surgical scenario.

[0067] In some embodiments, the differential gear set further includes an auxiliary connecting rod 323, a first bevel gear set, a second bevel gear set, a third bevel gear set, a fourth bevel gear 327, and a transmission bevel gear 328. The first bevel gear set is connected to the first input shaft 321, the second bevel gear set is rotatably connected to the first input shaft 321 via the auxiliary connecting rod 323, the second bevel gear set is rotatably connected to the second input shaft 322 via the auxiliary connecting rod 323, and the fourth bevel gear 327 is connected to the second output shaft. The first bevel gear set includes a first driving gear 3241 and a first driven gear 328. 242, the second bevel gear set includes a second driving gear 3251 and a second driven gear 3252, the third bevel gear set includes a third driving gear 3261 and a third driven gear 3262, the first driving gear 3241 meshes with the third driving gear 3261, the first driven gear 3242 meshes with the second driving gear 3251, the second driving gear 3251 meshes with the fourth bevel gear 327, the output rotating member 331 is connected to the transmission bevel gear 328, and the second driven gear 3252 and the third driven gear 3262 mesh with the transmission bevel gear 328.

[0068] Specifically, such as Figures 1-4As shown, the axial direction of the first input shaft 321 coincides with the axial direction of the second input shaft 322, and the first input shaft 321 and the second input shaft 322 are arranged at intervals along the second axial direction. The first input shaft 321 is connected to the first bevel gear set—both the first driving gear 3241 and the first driven gear 3242 are mounted or formed on this shaft; it is rotatably connected to the second bevel gear set through an auxiliary connecting rod 323 (that is, one end of the auxiliary connecting rod 323 is connected to the first input shaft 321 by a revolute joint, so that the auxiliary connecting rod 323 can rotate around the first input shaft 321).

[0069] The second input shaft 322 is connected to the fourth bevel gear 327; it is rotatably connected to the second bevel gear set via an auxiliary connecting rod 323 (i.e., the other end of the auxiliary connecting rod 323 is connected to the second input shaft 322 via a revolute joint, allowing the auxiliary connecting rod 323 to rotate around the second input shaft 322). Thus, the two ends of the auxiliary connecting rod 323 are connected to the two input shafts respectively, forming a floating bridge component between the two input shafts. This enables the second transmission component 32 to rotate under the drive of the first transmission component 31.

[0070] The first driving gear 3241 (on the first shaft) meshes with the third driving gear 3261 (the driving wheel of the third bevel gear set); the first driven gear 3242 (on the first shaft) meshes with the second driving gear 3251 (the driving wheel of the second bevel gear set); the second driving gear 3251 (on the second bevel gear set) meshes with the fourth bevel gear 327 (on the second input shaft 322); the second driven gear 3252 (the driven wheel of the second bevel gear set) and the third driven gear 3262 (the driven wheel of the third bevel gear set) both mesh with the transmission bevel gear 328 (output end).

[0071] Since the two ends of the auxiliary link 323 are rotatably connected to the two input shafts respectively, and the second bevel gear set is mounted on the auxiliary link 323, the following occurs: when the two input shafts rotate in the same direction at the same speed, the auxiliary link 323 remains relatively stationary, and the motions of the two paths are superimposed in the same direction on the transmission bevel gear 328, resulting in a composite motion (such as the linear movement of the output rotating component 331); when the two input shafts rotate in opposite directions or at different speeds, the auxiliary link 323 swings accordingly, and the position of the second bevel gear set changes, causing the motions of the two paths to produce a differential effect on the transmission bevel gear 328, resulting in a differential motion (such as the swinging or rotational mode of the output rotating component 331).

[0072] In other words, the second drive component 22 and the third drive component 23 drive the corresponding input shafts to rotate synchronously. When the first drive component 21 is stationary, the first bevel gear set and the fourth bevel gear 327 rotate. When the first driving gear 3241 and the fourth bevel gear 327 rotate at the same speed, the second driven gear 3252 and the third driven gear 3262 also rotate at the same speed. At this time, no differential motion occurs, the transmission bevel gear 328 does not rotate, and the output rotating component 331 rotates around the first axis. The motion is transmitted to the actuator 34 through the output transmission component to move synchronously. This is how one rotational degree of freedom of the end effector is generated.

[0073] If the first drive component 21 is stationary and the first bevel gear set and the fourth bevel gear 327 have opposite mirror velocities, the second driven gear 3252 and the third driven gear 3262 also have opposite mirror velocities. At this time, only differential motion is generated. The output rotating component 331 rotates but does not rotate around the first axis. The rotation of the output rotating component 331 drives the ball screw to rotate, and the output transmission component generates linear motion, which in turn drives the actuator 34 to generate linear motion. This is the way in which one linear degree of freedom of the end effector is generated.

[0074] If the first drive component 21 rotates, and the second drive component 22 and the third drive component 23 drive the corresponding input shaft to rotate synchronously, so that the first bevel gear set and the fourth bevel gear 327 rotate in the same direction and at the same speed, then the entire mechanism and the actuator 34 will rotate around the second axis. This is another way to generate rotational degree of freedom of the end effector.

[0075] The above describes the driving method for decoupled individual motion of three degrees of freedom. When each driving component moves in a coupled manner, synchronous coupled motion of three degrees of freedom can be generated, realizing the combination of free motion of three degrees of freedom.

[0076] In some embodiments, the first driving gear 3241 and the third driving gear 3261 are the same gear, the first driven gear 3242, the second driving gear 3251 and the fourth bevel gear 327 are the same gear, and the second driven gear 3252, the third driven gear 3262 and the transmission bevel gear 328 are the same gear.

[0077] It is understandable that, such as Figures 1-4 Figures 1-4 As shown, the transmission ratio of all gear meshing pairs is 1:1, and there are no speed-increasing or speed-reducing components within the differential gear set. That is, the rotational speed of the output rotating component 331 has a purely linear addition / subtraction relationship with the rotational speeds of the two input shafts, without any nonlinear scaling due to different transmission ratios. Preferably, all gears are bevel gears with a cone angle of 45 degrees.

[0078] In other words, when gears of the same specification mesh, parameters such as meshing angle, tooth profile curvature radius, and overlap ratio are completely symmetrical, and the meshing forces between the gears are equal in magnitude and symmetrical in direction. During differential operation, the radial and axial forces generated at each meshing point cancel each other out under the symmetrical structure, keeping the overall force on the differential gear set in a balanced state. This self-balancing characteristic significantly reduces vibration and noise during operation, improves transmission smoothness, and makes force feedback during surgical procedures purer and more realistic, avoiding interference with the surgeon's precise operational judgment due to mechanical vibration. In summary, the multi-degree-of-freedom minimally invasive surgical end effector of this invention has the following effects: The multi-degree-of-freedom minimally invasive surgical end effector of this invention can ensure that the actuator always passes through a fixed point in the three degrees of freedom of the first axis pitch, the second axis swing, and the first direction feed. This feature is suitable for minimally invasive surgery, and the fixed point is the surgical incision.

[0079] The multi-degree-of-freedom minimally invasive surgical end effector of this invention combines a multi-link mechanism design with a lead screw linear motion mechanism design, so that all the links are located on the same plane, but can achieve three degrees of freedom in space, saving the physical space occupied by the mechanism and making use of the compact layout in the operating room; the design of the multi-link mechanism increases the stiffness between the links inside the mechanism, and the linear motion achieved by the lead screw also has high linear accuracy.

[0080] The multi-degree-of-freedom minimally invasive surgical end effector of this invention uses a differential gear set that provides up to twice the motor torque to the ball screw motion. At the same time, the ball screw itself has a large transmission ratio. The combination of the two makes the linear motion of the end effector have greater force, and a larger linear feed force can be achieved with a smaller motor. This is of great significance in punctures in rigid surgeries such as orthopedic surgery.

[0081] The multi-degree-of-freedom minimally invasive surgical end effector of this invention utilizes a differential gear set design to achieve coupled control of the pitch, rotation, and translational motions of the execution unit. The bevel gears allow the drive unit to be fixed on a fixed platform base and will not move with the transmission unit, reducing the overall rotational inertia of the mechanism and optimizing the problem of the doctor's narrow field of vision.

[0082] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" 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 this invention and simplifying the description, and are not intended to 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 this invention.

[0083] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0084] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0085] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0086] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0087] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A multi-degree-of-freedom minimally invasive surgical end effector, characterized in that, include: Base; A drive assembly, the drive assembly comprising a first drive component, a second drive component, and a third drive component fixedly disposed on the base; A transmission assembly includes a first transmission component, a second transmission component, and an actuating component. The first transmission component is rotatably connected to a first driving component about a first axial direction, and the first driving component drives the first transmission component to rotate about a second axial direction. The second axial direction is parallel to the axial direction of the output shaft of the first driving component, and the first axial direction is orthogonal to the second axial direction. The second transmission component is connected to the second drive component and the third drive component. The first end of the execution component is connected to the first transmission component and the second transmission component through a connecting component. The second transmission component has a first state and a second state. In the first state, the drive component is used to drive the second end of the execution component to rotate about a first axis through the second transmission component. In the second state, the drive component is used to drive the execution component to move along a first direction through the second transmission component. The first direction has an angle between it and the plane containing the first axis and the second axis.

2. The multi-degree-of-freedom minimally invasive surgical end effector according to claim 1, characterized in that, The first transmission component includes a first connecting rod, a second connecting rod, and a third connecting rod. The connecting component includes a first crossbar. There are two first connecting rods and two second connecting rods, which are spaced apart along a second axial direction. The first end of the first connecting rod is rotatably connected to the third connecting rod, and the second end of the first connecting rod is rotatably connected to the base and the output shaft of the first driving component, respectively. The lines connecting the second ends of the first connecting rod, the third connecting rod, and the second connecting rod form a parallelogram structure. The first end of the second link is rotatably connected to the third link, and the second end of each of the second links is rotatably connected to the first end of the first crossbar. The second link, the third link, and the first end of the first crossbar form a parallelogram structure.

3. The multi-degree-of-freedom minimally invasive surgical end effector according to claim 2, characterized in that, The transmission assembly further includes a bearing housing disposed on the base. The bearing housing and the first drive component are spaced apart along the second axis. The second end of a first connecting rod is rotatably connected to the bearing housing. The axis of the bearing housing is parallel to the second axis.

4. The multi-degree-of-freedom minimally invasive surgical end effector according to claim 3, characterized in that, The first connecting rod includes a straight rod and a curved rod connected together. The straight rod and the curved rod are generally L-shaped. The straight rod is connected to the third connecting rod, and the curved rod is connected to the bearing seat and the output shaft of the first drive component, respectively.

5. The multi-degree-of-freedom minimally invasive surgical end effector according to claim 2, characterized in that, The connecting component further includes a second crossbar, the two ends of which are rotatably connected to the second transmission component and the actuation component, respectively. The second end of the first crossbar, the first end of the actuation component, the second crossbar, and a portion of the second transmission component form a parallelogram structure.

6. The multi-degree-of-freedom minimally invasive surgical end effector according to claim 5, characterized in that, The second crossbar is located on the side of the first crossbar away from the base.

7. The multi-degree-of-freedom minimally invasive surgical end effector according to claim 5, characterized in that, The second transmission component includes a differential gear set and an output component. The differential gear set includes a first input shaft and a second input shaft, which are respectively connected to the output shaft of the second drive component and the output shaft of the third drive component. The output component includes an output rotating component and an output moving component. The output rotating component meshes with the differential gear set via gears. The output moving component is sleeved on the output rotating component. The first crossbar and the second crossbar are rotatably connected to the output moving component. The output rotating component rotates to drive the output moving component to move along the first direction.

8. The multi-degree-of-freedom minimally invasive surgical end effector according to claim 7, characterized in that, The transmission method of the output component includes one of the following: screw and nut helical transmission, ball spline helical transmission, helical groove pin transmission, and differential thread transmission.

9. The multi-degree-of-freedom minimally invasive surgical end effector according to claim 8, characterized in that, The differential gear set further includes an auxiliary connecting rod, a first bevel gear set, a second bevel gear set, a third bevel gear set, a fourth bevel gear, and a transmission bevel gear. The first bevel gear set is connected to the first input shaft. The second bevel gear set is rotatably connected to the first input shaft via the auxiliary connecting rod, and the second bevel gear set is rotatably connected to the second input shaft via the auxiliary connecting rod. The fourth bevel gear is connected to the second output shaft. The first bevel gear set includes a first driving gear and a first driven gear; the second bevel gear set includes a second driving gear and a second driven gear; and the third bevel gear set includes a third driving gear and a third driven gear. The first driving gear meshes with the third driving gear, the first driven gear meshes with the second driving gear, the second driving gear meshes with the fourth bevel gear, the output rotating component is connected to the transmission bevel gear, and the second driven gear and the third driven gear mesh with the transmission bevel gear.

10. The multi-degree-of-freedom minimally invasive surgical end effector according to claim 9, characterized in that, The first driving gear and the third driving gear are the same gear; the first driven gear, the second driving gear and the fourth bevel gear are the same gear; and the second driven gear, the third driven gear and the transmission bevel gear are the same gear.

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