A multi-joint flexible robot for single-port laparoscopic surgery

Abstract

A multi-joint flexible robot for single-hole endoscopic surgery, comprising a clamp mechanism, an execution arm, a yaw driving mechanism and a rotation and translation driving mechanism; the clamp mechanism comprises a sliding pin, a driving slider, a first thermal insulation piece, a first spring, a second spring, a second thermal insulation piece, a fixed sleeve and two clamp arms; the first thermal insulation piece, the first spring, the driving slider, the second spring and the second thermal insulation piece are sequentially arranged in the fixed sleeve, the first spring, the driving slider and the second spring can slide relative to the fixed sleeve, the driving slider extends to the clamp arms with a sliding handle arranged in the first spring, the non-clamping ends of the two clamp arms are respectively provided with arc-shaped holes, and the outer wall of the fixed sleeve is provided with a guide hole in the axial direction; the sliding handle can slide in the arc-shaped hole and the guide hole. The robot is convenient to assemble and maintain, eliminates the motion coupling phenomenon caused by clamp driving, can realize high motion accuracy, and is convenient for doctors to realize more delicate operation and processing.

Description

Technical Field

[0001] This invention relates to the field of robotics, and more specifically to a multi-joint flexible robot for single-port laparoscopic surgery. Background Technology

[0002] Compared to traditional minimally invasive surgical methods, robot-assisted surgery offers significant advantages, such as simplified operation, shorter learning cycles, less trauma to the human body, higher accuracy, and reduced surgical failure rates. In complex scenarios with limited space, surgical robots must possess sufficient flexibility, and single-port laparoscopic surgical robots offer a clear advantage in such situations. Unlike traditional rigid surgical instruments, the main body of these robots is often designed as a flexible, freely bendable actuator arm. Various surgical tools, such as endoscopes, clamps, and high-frequency electrosurgical units, can be mounted at the end of the actuator arm. During surgery, multiple surgical tools are inserted into the lesion area simultaneously through the incision, and the surgeon controls the surgical robot to complete the corresponding surgical procedures using a remote control hand at the master end.

[0003] Currently, the opening and closing motion of grippers in robots is often controlled by external wire drives. Because of the external force at the end of the actuator arm, the decrease in motion accuracy due to motion coupling is difficult to avoid. In addition, friction between the actuator arm and the joint also affects motion accuracy. Summary of the Invention

[0004] This invention overcomes the limitations of existing technologies by providing a multi-joint flexible robot for single-port laparoscopic surgery. The robot is easy to assemble and maintain, and its overall structure eliminates motion coupling caused by clamp drives, achieving high motion precision and enabling surgeons to perform more precise operations.

[0005] A multi-joint flexible robot for single-port laparoscopic surgery includes a clamping mechanism, an actuator arm, a yaw drive mechanism, and a rotation and translation drive mechanism. The clamping mechanism has opening and closing degrees of freedom. The clamping mechanism is connected to the actuator arm, which is connected to the yaw drive mechanism. The actuator arm is equipped with a drive wire controlled by the yaw drive mechanism to realize the bending motion of the actuator arm. The yaw drive mechanism is connected to the rotation and translation drive mechanism and is controlled by the rotation and translation drive mechanism to perform rotation and translation motion. The clamping mechanism includes a sliding pin, a driving slider, a first heat-insulating component, a first spring, a second spring, a second heat-insulating component, a fixing sleeve, and two clamping arms. One end of the fixed sleeve is provided with two openable clamping arms, and the other end of the fixed sleeve is connected to the actuator arm. The first heat insulation component, the first spring, the drive slider, the second spring, and the second heat insulation component are sequentially arranged inside the fixed sleeve. The first heat insulation component and the second heat insulation component are fixed on the inner wall of the fixed sleeve. The first spring, the drive slider, and the second spring can slide relative to the fixed sleeve. The two ends of the first spring abut against the first heat insulation component and the drive slider, respectively, and the two ends of the second spring abut against the drive slider and the second heat insulation component, respectively. The drive slider extends into the clamp arm and has a sliding handle placed inside the first spring. One end of the sliding handle is connected to a sliding pin. The non-clamping ends of the two clamp arms are respectively opened with arc-shaped holes. The outer wall of the fixed sleeve has a guide hole along the axial direction. The sliding handle can slide in the arc-shaped holes and the guide holes. The opening and closing movement of the clamp arms is controlled by pulse width modulation to control the input voltage at both ends of the first spring and the second spring to control the spring temperature, thereby changing the stiffness of the first spring and the second spring to generate the driving force of the drive slider on the clamp movement.

[0006] Furthermore, the actuator arm includes a flexible arm and a rigid arm. The two ends of the flexible arm are respectively connected to the clamping mechanism and the rigid arm. The flexible arm includes a top joint, a reversing joint, a joint group one, and a joint group two. The top joint, joint group one, reversing joint, and joint group two are connected in series. The clamping mechanism is fixed to the top joint. Joint group two is connected to the rigid arm. A drive wire controlled by a yaw drive mechanism is fixed in joint group one and joint group two respectively to realize the bending movement of joint group one and joint group two.

[0007] Furthermore, both joint group one and joint group two contain multiple joints with the same structure stacked together, and radial misalignment is limited by a drive wire. The deflection movement of adjacent joints is accomplished by the relative sliding of the joint flange and the joint groove.

[0008] Furthermore, eight wire guide holes are evenly distributed on the peripheral side of each joint to serve as channels for the drive wire. Each wire guide hole is a variable diameter hole, including blind holes on both sides and a central hole that communicates with the blind holes. The diameter of the central hole is smaller than the inner diameter of the blind holes.

[0009] Furthermore, the yaw drive mechanism includes a yaw drive motor, a lead screw pair, a front plate, a slider support, a guide rod, a first frame, a second frame, a drive wire retainer, a driver, and an internal gear ring. The front plate, the first frame, and the second frame are arranged sequentially. Multiple guide rods and eight sets of lead screw pairs are arranged circumferentially between the front plate and the first frame. The two ends of the lead screw of each set of lead screw pairs are rotatably mounted on the front plate and the first frame. Eight yaw drive motors are fixed on the first frame, and the output end of each yaw drive motor is connected to the corresponding lead screw. The drive wire retainer is fixedly connected to the slider support, and the slider support is fixedly connected to the lead screw nut. The slider support is slidably mounted on the guide rod. A drive wire guide assembly is provided on the front plate and is connected to the actuator arm. The first frame and the second frame are connected. The front plate and the second frame are rotatably mounted on the rotary translation drive mechanism. The second frame is provided with a driver that can control the yaw drive motor and an internal gear ring driven by the rotary translation drive mechanism.

[0010] Furthermore, the rotational translation drive mechanism includes a bracket, a fixed base plate, a fixed slider, and a lead screw module; the yaw drive mechanism is rotatably mounted on the bracket, the bracket is provided with a drive component that can drive the internal gear ring to rotate, the bracket is mounted on the fixed base plate, the fixed slider is threadedly connected to the lead screw of the lead screw module, and the fixed base plate is mounted on the fixed slider.

[0011] The advantages of this invention compared to the prior art are: The clamp uses a shape memory alloy spring. The alloy wire is heated by an electric current to cause the spring to deform, which in turn drives the clamp end to open and close. Compared with the commonly used pull-wire drive method, this structure effectively avoids the motion coupling phenomenon caused by the pulling force that causes the clamp arm to open and close.

[0012] A variable-diameter wire guide hole was designed for the joints of the flexible actuator arm. Compared with a constant-diameter wire guide hole, the variable-diameter wire guide hole has a thinner wall thickness. When the flexible actuator arm is bent, the horizontal component force borne by a single joint is smaller. Therefore, there is less friction between the hole wall and the elastic drive wire, which is especially advantageous when the flexible actuator arm is under large bending deformation.

[0013] The surgical robot of this invention is easy to assemble and maintain. Its overall structure eliminates the motion coupling phenomenon caused by the clamp drive, which can achieve high motion accuracy and make it easier for doctors to perform more precise operations.

[0014] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments: Attached Figure Description

[0015] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a three-dimensional view of the clamping mechanism; Figure 3This is a cross-sectional view of the clamping mechanism; Figure 4 This is a structural diagram of the fixed sleeve; Figure 5 This is a structural diagram of a rigid arm; Figure 6 A structural diagram showing the connection between the clamping mechanism, the flexible arm, and the rigid arm; Figure 7 Structural diagrams of the flexible arm and the rigid arm; Figure 8 This is a structural diagram of joint A with articular flanges; Figure 9 This is a structural diagram of joint A with articular grooves; Figure 10 This is a 3D view of the reversing joint; Figure 11 A three-dimensional view of a reversing joint with grooves; Figure 12 A three-dimensional view showing the connection between the yaw drive mechanism and the rotary translation drive mechanism; Figure 13 A 3D view of the yaw drive mechanism as seen from the front. Figure 14 A 3D view of the yaw drive mechanism as seen from the rear. Figure 15 A three-dimensional view of the drive wire guide assembly as seen from the front. Figure 16 A three-dimensional view of the drive wire guide assembly as seen from the rear. Figure 17 A three-dimensional view of the rotation and translation drive mechanism; Figure 18 This is a structural diagram of the front panel; Figure 19 Here is a structural diagram of driver board one; Figure 20 Here is a structural diagram of driver board two; Figure 21 Here is a structural diagram of driver board three; Figure 22 This is a structural diagram of the rear panel. Detailed Implementation

[0016] The embodiments of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings. Unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning understood by those skilled in the art.

[0017] Combination Figures 1-9 This embodiment describes a multi-joint flexible robot for single-port laparoscopic surgery, comprising a clamping mechanism 1, an actuator arm 2, a yaw drive mechanism 3, and a rotation and translation drive mechanism 4. The clamping mechanism 1 has a degree of freedom to open and close. The clamping mechanism 1 is connected to the execution arm 2. The execution arm 2 is connected to the yaw drive mechanism 3. The execution arm 2 is equipped with a drive wire controlled by the yaw drive mechanism 3 to realize the bending motion of the execution arm 2. The yaw drive mechanism 3 is connected to the rotation and translation drive mechanism 4 and is controlled by the rotation and translation drive mechanism 4 to perform rotation and translation motion. The clamping mechanism 1 includes a sliding pin 1-1, a driving slider 1-2, a first heat insulation component 1-3, a first spring 1-4, a second spring 1-5, a second heat insulation component 1-6, a fixing sleeve 1-8, and two clamping arms 1-9. One end of the fixed sleeve 1-8 is provided with two openable clamping arms 1-9, and the other end of the fixed sleeve 1-8 is connected to the actuator arm 2. The first heat insulation component 1-3, the first spring 1-4, the drive slider 1-2, the second spring 1-5, and the second heat insulation component 1-6 are sequentially arranged inside the fixed sleeve 1-8. The first heat insulation component 1-3 and the second heat insulation component 1-6 are fixed on the inner wall of the fixed sleeve 1-8. The first spring 1-4, the drive slider 1-2, and the second spring 1-5 can slide relative to the fixed sleeve 1-8. The two ends of the first spring 1-4 abut against the first heat insulation component 1-3 and the drive slider 1-2, respectively. The two ends of the second spring 1-5 abut against the drive slider 1-2 and the second heat insulation component 1-6, respectively. The drive slider 1-2 extends into the clamping arm 1-9, with a sliding handle 1-20 housed within the first spring 1-4. One end of the sliding handle 1-20 is connected to the sliding pin 1-1. The non-clamping ends of the two clamping arms 1-9 each have an arc-shaped hole 1-90. A guide hole 1-80 is axially formed on the outer wall of the fixing sleeve 1-8. The sliding handle 1-20 can slide within the arc-shaped hole 1-90 and the guide hole 1-80. The opening and closing motion of the clamping arms 1-9 is controlled by pulse width modulation, which controls the input voltage at both ends of the first and second springs to regulate the spring temperature. This, in turn, changes the stiffness of the first spring 1-4 and the second spring 1-5, generating the driving force of the drive slider 1-2 on the clamping arms 1-9. The two clamping arms 1-9 are hinged together by a fixing pin 1-10, achieving a scissor-like motion.

[0018] The purpose of this design is to address the issue of low control precision in existing continuous-body flexible surgical arm robots due to severe motion coupling and high friction. The clamping arm 1-9, rotating pin 1-10, and sliding pin 1-1 form a linkage-slider mechanism. Driving slider 1-2 causes sliding pin 1-1 to reciprocate along the grooved guide rail of fixed sleeve 1-8, thus opening and closing the clamping arm 1-9.

[0019] The driving force for the movement of slider 1-2 is achieved by the tension difference generated by the stiffness change of the first spring 1-4 and the second spring 1-5. Both the first spring 1-4 and the second spring 1-5 are made of shape memory alloy, optionally CuZnAl shape memory alloy springs. The springs undergo different phase transitions according to temperature changes, thereby changing their shape and stiffness. The outer surfaces of the first spring 1-4 and the second spring 1-5 are plated with an insulating layer (such as alumina), and a wire-type temperature sensor is attached externally. Wires are led out from both ends of the first spring 1-4 and the second spring 1-5, as well as from the sensor. The wires pass sequentially through the first heat-insulating component 1-3, the second heat-insulating component 1-6, and the fixing sleeve 1-8, finally transmitting the signal through the actuator 2 to the controller. Figure 4 The diagram shows the structure of the fixed sleeve 1-8, which is hollow inside and serves as a coolant storage layer. Specifically, the fixed sleeve 1-8 and the threaded seat 1-11 are machined separately and then joined together. The threaded post at the rear end of the threaded seat 1-11 is screwed into the threaded hole of the actuator arm 2 for assembly.

[0020] For the opening and closing movement of the clamp arms 1-9, the spring temperature can be controlled by adjusting the input voltage at both ends of the first spring 1-4 and the second spring 1-5 using pulse width modulation (PWM) technology. This changes the shape and stiffness of the first spring 1-4 and the second spring 1-5 to generate the driving force for the movement of the clamp arms 1-9. For example, heating the first spring 1-4 generates an upward driving force in both the first spring 1-4 and the second spring 1-5, driving the slider 1-2 to move the sliding pin 1-1 upward, thus opening the clamp arms 1-9. Conversely, heating the second spring 1-5 achieves the closing movement of the clamp arms 1-9.

[0021] The purpose of this embodiment is to: compared to the traditional wire-driven clamping structure, this clamping mechanism 1 can drive the clamping end to open and close without relying on external forces to achieve the opening and closing motion. Instead, it uses the tension generated by an internal spring as the driving force to control the movement of the clamp, eliminating the motion coupling phenomenon caused by external driving forces. This further improves the motion accuracy of the surgical robot compared to the wire-driven method.

[0022] The robot in this embodiment is easy to assemble and maintain. Its overall structure eliminates the motion coupling phenomenon caused by the clamp drive, which can achieve high motion accuracy and make it easier for doctors to perform more precise operations.

[0023] Specifically, such as Figure 5 -like Figure 9 As shown, the actuator 2 includes a flexible arm 2-1 and a rigid arm 2-2, with the two ends of the flexible arm 2-1 connected to the clamping mechanism 1 and the rigid arm 2-2, respectively. The flexible arm 2-1 includes a top joint 2-11, a reversing joint 2-12, a joint group one 2-13, and a joint group two 2-14; Top joint 2-11, joint group one 2-13, reversing joint 2-12 and joint group two 2-14 are connected in series; The clamping mechanism 1 is fixedly connected to the top joint 2-11, and the joint assembly 2-14 is connected to the rigid arm 2-2; The joint assembly 2-13 and the joint assembly 2-14 are respectively fixed with drive wires controlled by the yaw drive mechanism 3 to realize the bending movement of the joint assembly 2-13 and the joint assembly 2-14.

[0024] The actuator arm 2 can realize the opening and closing of the clamp arms 1-9 and the deflection movement of the actuator arm 2. The joint group 1 2-13 and joint group 2-14 in the flexible arm 2-1 have two degrees of freedom: roll and pitch. The actuator arm as a whole has a total of 4 degrees of freedom. The clamping mechanism 1 has 1 degree of freedom. The yaw drive mechanism 3 and the rotation and translation drive mechanism 4 can realize the rotation and axial translation of the actuator arm 2, respectively. Therefore, the robot as a whole contains 7 degrees of freedom. The actuator arm 2 can reach the same target lesion area with a variety of selectable postures, which has high flexibility and makes it easy for doctors to operate the robot to complete complex surgeries in narrow spaces.

[0025] Optionally, such as Figure 5 As shown, the rigid arm 2-2 includes a base joint 2-21, a base guide rod 2-22, and a base rod sleeve 2-23. The base joint 2-21 is welded to the base guide rod 2-22. The base rod sleeve 2-23 is sleeved on the outside of the base guide rod 2-22 and has a clearance fit with the base guide rod 2-22. Eight square slots are evenly distributed at 45° intervals on the outer periphery of the base guide rod 2-22. The drive wire drives the actuator arm 2 to achieve the target movement through the square slots.

[0026] Furthermore, such as Figure 8 and Figure 9 As shown, joint group 1 2-13 and joint group 2 2-14 both contain multiple joints A with the same structure stacked together, and radial misalignment is limited by the through-running drive wire. The deflection movement of adjacent joints A is accomplished by the relative sliding of the joint flange A1 and the joint groove A2.

[0027] The top joint 2-11 is located at the very end of the entire actuator arm 2. Joint group one 2-13 and reversing joint 2-12 form the first-stage arm, and joint group two 2-14 and top joint 2-11 form the second-stage arm. Each stage arm is driven by four drive wires (not shown in the figure). Bolt holes are evenly distributed on the cylindrical outer surface of top joint 2-11 and reversing joint 2-12 for fixing the drive wires. The drive wires are made of shape memory alloy material (such as nickel-titanium alloy), a superelastic material that maintains the shape of the actuator arm. The structure of reversing joint 2-12 is as follows... Figures 10-11 As shown.

[0028] Better, such as Figure 8 and Figure 9 As shown, eight wire passage holes A3 are evenly distributed on the peripheral side of each joint A, serving as channels for the drive wire. Each wire passage hole A3 is a variable diameter hole, including blind holes A31 on both sides and a central hole A32 that communicates with the blind holes. The diameter of the central hole A32 is smaller than the inner diameter of the blind hole A31.

[0029] The purpose of this design is to provide eight guide wire holes evenly distributed around the periphery of joint A, serving as channels for the drive wire. The through holes at the center of joint group one (2-13) and joint group two (2-14) are used as cable channels for driving the clamp arms 1-9. The eight evenly distributed wire holes are variable-diameter holes, meaning the diameter at both ends of the through hole is larger than the diameter in the middle. The advantage of this structure is that, due to the reduced contact length between the wall of a single joint A hole and the drive wire, the horizontal component of the tension along the tangential direction of the drive wire during bending motion is reduced. Therefore, the friction between the drive wire and the hole wall is reduced, thereby improving the overall motion accuracy of the actuator arm.

[0030] As a possible implementation method, such as Figures 12-14 As shown, the yaw drive mechanism 3 includes a yaw drive motor 3-1, a lead screw pair 3-2, a front plate 3-3, a slider support 3-4, a guide rod 3-5, a first frame 3-6, a second frame 3-7, a drive wire retainer 3-8, a driver 3-9, and an internal gear ring 3-10. Front plate 3-3, frame one 3-6, and frame two 3-7 are arranged sequentially. Multiple guide rods 3-5 and eight sets of lead screw pairs 3-2 are arranged circumferentially between front plate 3-3 and frame one 3-6. The two ends of the lead screw in each set of lead screw pairs 3-2 are rotatably mounted on front plate 3-3 and frame one 3-6. Eight yaw drive motors 3-1 are fixed on frame one 3-6. The output end of each yaw drive motor 3-1 is connected to the corresponding lead screw. Drive screw retainer 3-8 is fixedly connected to slider support 3-4. Slider support 3-4 and... The lead screw pair 3-2 is fixedly connected to the lead screw nut. The slider support 3-4 is slidably mounted on the guide rod 3-5. The front plate 3-3 is provided with a drive wire guide assembly 3-11, which is connected to the actuator arm 2. Frame 1 3-6 is connected to frame 2 3-7. The front plate 3-3 and frame 2 3-7 are rotatably mounted on the rotary translation drive mechanism 4. Frame 2 3-7 is provided with a driver 3-9 that can control the yaw drive motor 3-1 and an internal gear ring 3-10 driven by the rotary translation drive mechanism 4.

[0031] Furthermore, such as Figure 14 , Figures 18-22 As shown, frame 3-6 includes drive plate 3-61 and drive plate 3-62. Drive plate 3-61 and drive plate 3-62 are spaced apart and connected by bolts. A coupling 3-13 connecting the output end of the yaw drive motor 3-1 and the lead screw is arranged between them. Frame 2 3-7 includes drive plate 3 3-71 and rear plate 3-72. Drive plate 3 3-71 and rear plate 3-72 are spaced apart and connected by bolts. A driver 3-9 is arranged between them. An internal gear ring 3-10 is embedded in the middle of the rear plate 3-72. Drive wire guide assembly 3-11 and drive plate 3 3-71 are rotatably mounted on the rotary translation drive mechanism 4.

[0032] The purpose of this setup is as follows: the lead screw of lead screw pair 3-2 is interference-fitted with the bearing seats at both ends and then fixed to the front plate 3-3 and drive plate 3-61 respectively via threaded connection. The slider support 3-4 is placed on the slider and connected to it via threads. The central circular hole of slider support 3-4 is clearance-fitted with the guide rod 3-5 guided by slider support 3-4. Under the linear motion of the slider lead screw nut, slider support 3-4 can reciprocate relative to the guide rod 3-5. The two ends of guide rod 3-5 are fixed with nuts through the circular through holes of front plate 3-3 and drive plate 3-61 respectively, thus limiting the direction of movement of the slider and drive wire. The end of the drive wire is placed in the fixing hole of drive wire retainer 3-8 and then tightened with bolts. The rear thread of drive wire retainer 3-8 is screwed into the internal thread hole of tension sensor 3-11. The tail of tension sensor 3-11 is equipped with a tension sensor fixing seat, converting the three-hole thread at the tail of tension sensor 3-11 into a single-hole thread.

[0033] In this configuration, the tension sensor 3-11 is used to acquire the tension when the drive wire drives the actuator arm 2 to move. The tension sensor 3-11 sends the measured tension data to the controller for processing. The tension sensor mounting base and the slider support 3-4 are connected by a handwheel 3-12. Rotating the handwheel 3-12 adjusts the preload of each drive wire, which is used for calibrating the initial tension of each drive wire. During the operation of the surgical robot, the tension sensor 3-11 can monitor the tension changes of each drive wire in real time and provide feedback on abnormal states of the system.

[0034] The power source for the lead screw assembly 3-2 is the yaw drive motor 3-1 (the selected motor can be a DC motor or a stepper motor). The yaw drive motor 3-1 is fixed on the second drive plate 3-62 and connected to the end of the lead screw via a coupling 3-13, providing rotational power to the lead screw. The front plate 3-3, the first drive plate 3-61, the second drive plate 3-62, the third drive plate 3-71, and the rear plate 3-72 divide the deflection drive mechanism 3 into four levels: the lead screw level, the connection level, the motor level, and the electrical control level. Each level is fixedly connected by a drive box mounting rod, which allows for quick assembly and disassembly. The parts have a simple structure, low cost, and are easy to maintain later.

[0035] Drive board 1 (3-61) and drive board 2 (3-62) are fixedly connected by drive box mounting rods in the connecting layer. Drive box 2 (3-62) and drive board 3 (3-71) are fixedly connected by drive box mounting rods in the motor layer. Drive board 3 (3-71) and rear plate (3-72) are fixedly connected by drive box mounting rods in the electrical control layer. The drive unit of the surgical robot is grouped into groups according to the mechanism type, and different levels can be assembled separately, which facilitates the later updates and maintenance of the surgical robot.

[0036] The electrical control layer is where the actuator 3-9 is mounted. The actuator mounting plate is fixed to the sides of the drive plate 3-71 and the rear plate 3-72 by bolts. The actuator 3-9 is mounted on the inner side of the actuator mounting plate. The control relationship between each yaw drive motor 3-1 and the actuator 3-9 corresponds one-to-one along the frame axis. During the overall rotation of the frame, the actuator 3-9 and the yaw drive motor 3-1 remain relatively stationary.

[0037] The movement process of the drive end (actuator arm 2) of the deflection drive mechanism 3 is as follows: The driver 3-9 sends control commands to the deflection drive motor 3-1, which drives the lead screw pair 3-2 and the slider support 3-4 to move. The motor drives the lead screw to rotate, which in turn drives the slider support 3-4 to move axially. In turn, the slider support 3-4 drives the drive wire holder 3-8 on it to move axially, realizing the reciprocating motion of the drive wire. The ends of drive wire 1, drive wire 3, drive wire 5, and drive wire 7 are fixed to the reversing joint 2-12. The reciprocating motion of the drive wires controls the yaw motion of the first-stage arm (joint group 1 2-13 and reversing joint 2-12). The ends of drive wire 2, drive wire 4, drive wire 6, and drive wire 8 are fixed to the top joint 2-11, which controls the yaw motion of the second-stage arm (joint group 2-14 and top joint 2-11). Each stage arm has two degrees of freedom: roll and pitch.

[0038] As another possible implementation method, such as Figure 15 and Figure 16 As shown, the drive wire guide assembly 3-11 includes a front guide plate 3-111, a rear guide plate 3-112, a drive wire guide tube 3-113, and a guide support rod 3-114; the front guide plate 3-111 and the rear guide plate 3-112 are connected by the guide support rod 3-114 located between them, the rear guide plate is fixedly connected to the front plate 3-3, and the drive wire guide tube 3-113 is provided between the front guide plate 3-111 and the rear guide plate 3-112.

[0039] The long shaft of the front guide plate 3-111 has a transition fit with the bearing, and a square slot is provided for mounting a retaining spring to limit the bearing's position. The front ends of the eight drive wire guide tubes 3-113 are respectively bonded to the eight array holes of the front guide plate 3-111 using a transition fit method, and the rear ends are connected to the eight array holes 3-1120 of the rear guide plate 3-112 in the same way. The rear end thread of the guide support rod 3-114 is connected to the threaded hole of the rear guide plate 3-112, and the front end thread of the guide support rod 3-114 extends out of the through hole of the front guide plate 3-111 and is fixed with a nut, thereby ensuring the overall rigidity of the guide assembly 3-111. The rear guide plate 3-112 is fixed to the front plate 3-3 through the end thread of the guide rod.

[0040] The front guide plate 3-111 and the base guide rod 2-22 are connected by a locating pin and a coupling. The locating pin ensures that the array of through holes in the front guide plate 3-111 is precisely aligned with the array of square slots in the base guide rod 2-22. The entire actuator arm 2 can be quickly replaced by disassembling this part, facilitating the later maintenance and expansion of the surgical robot.

[0041] In another possible implementation, such as Figure 14 and Figure 17 As shown, the rotation and translation drive mechanism 4 includes a bracket 4-1, a fixed base plate 4-2, a fixed slider 4-3, and a lead screw module 4-4; The yaw drive mechanism 3 is rotatably mounted on the bracket 4-1. The bracket 4-1 is equipped with a drive assembly that can drive the internal gear ring 3-10 to rotate. The bracket 4-1 is mounted on the fixed base plate 4-2. The fixed slider 4-3 is threadedly connected to the lead screw of the lead screw module 4-4. The fixed base plate 4-2 is mounted on the fixed slider 4-3.

[0042] The drive assembly includes a central shaft 4-5, a rotary drive motor 4-6, and a gear 4-7. The central shaft 4-5 is fixed on the bracket 4-1. The yaw drive mechanism 3 is rotatably mounted on the bracket 4-1 and the central shaft 4-5. The rotary drive motor 4-6 is fixed on the bracket 4-1. The gear 4-7 is mounted on the output shaft of the rotary drive motor 4-6 and meshes with the internal gear ring 3-10.

[0043] The purpose of this configuration is as follows: the front guide plate 3-111 has a transition fit with the inner ring of bearing one, and the outer ring of bearing one has an interference fit with the front bracket bearing hole of bracket 4-1. Bearing three is installed in the center bearing hole of drive plate three 3-71 and is interference-fitted. The left end of the central shaft 4-5 has a transition fit with bearing three, and a retaining spring is inserted at the end to limit their relative positions. The right end of the central shaft 4-5 has a transition fit with bearing two, and a retaining spring is used to limit its position at the end. Bearing two has an interference fit with the rear bracket bearing mounting hole on bracket 4-1. The bottom of bracket 4-1 is fixed to both the front and rear brackets. The bottom of bracket 4-1 is fixed to the fixed slider 4-3 of the lead screw module 4-4 via a fixed base plate 4-2 and can move linearly on the slide table.

[0044] The rotary drive motor 4-6 drives the gear 4-7 to drive the overall deflection drive mechanism 3 to rotate around bearing one and bearing two as axes; the rotary motion is converted into linear motion through the lead screw module 4-4 (motor drives the lead screw to move), which in turn drives the overall deflection drive mechanism 3 to perform axial translational motion. Both of these motions directly reflect the motion of the actuator arm 2, providing the actuator arm 2 with a variety of selectable postures for the same position.

[0045] The present invention has been disclosed above with reference to preferred embodiments, but it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed structure and technical content to create equivalent embodiments without departing from the scope of the present invention, and all such modifications or alterations shall still fall within the scope of the present invention.

Claims

1. A multi-joint flexible robot for single-port laparoscopic surgery, comprising a clamping mechanism (1), an actuator arm (2), a yaw drive mechanism (3), and a rotational translation drive mechanism (4). The clamping mechanism (1) has opening and closing freedom. The clamping mechanism (1) is connected to the execution arm (2). The execution arm (2) is connected to the yaw drive mechanism (3). The execution arm (2) is equipped with a drive wire controlled by the yaw drive mechanism (3) to realize the bending motion of the execution arm (2). The yaw drive mechanism (3) is connected to the rotation and translation drive mechanism (4) and is controlled by the rotation and translation drive mechanism (4) to perform rotation and translation motion. Its features are: The clamping mechanism (1) includes a sliding pin (1-1), a driving slider (1-2), a first heat insulation component (1-3), a first spring (1-4), a second spring (1-5), a second heat insulation component (1-6), a fixing sleeve (1-8), and two clamping arms (1-9). One end of the fixed sleeve (1-8) is provided with two openable clamp arms (1-9), and the other end of the fixed sleeve (1-8) is connected to the actuator (2). The first heat insulation component (1-3), the first spring (1-4), the drive slider (1-2), the second spring (1-5), and the second heat insulation component (1-6) are sequentially arranged inside the fixed sleeve (1-8). The first heat insulation component (1-3) and the second heat insulation component (1-6) are fixed on the inner wall of the fixed sleeve (1-8). The first spring (1-4), the drive slider (1-2), and the second spring (1-5) can slide relative to the fixed sleeve (1-8). The two ends of the first spring (1-4) abut against the first heat insulation component (1-3) and the drive slider (1-2) respectively, and the two ends of the second spring (1-5) abut against the drive slider (1-2) and the second heat insulation component (1-6) respectively. The drive slider (1-2) extends into the clamp arm (1-9) and has a slide handle (1-20) placed inside the first spring (1-4). One end of the slide handle (1-20) is connected to the sliding pin (1-1). The non-clamping ends of the two clamp arms (1-9) are respectively opened with arc-shaped holes (1-90). The outer wall of the fixed sleeve (1-8) has a guide hole (1-80) opened along the axial direction. The slide handle (1-20) can slide in the arc-shaped hole (1-90) and the guide hole (1-80). The first spring (1-4) and the second spring (1-5) are both made of shape memory alloy. The opening and closing movement of the clamp arm (1-9) controls the spring temperature by controlling the input voltage at both ends of the first spring (1-4) and the second spring (1-5) through pulse width modulation, thereby changing the stiffness of the first spring (1-4) and the second spring (1-5) to generate the driving force of the drive slider on the clamp movement.

2. The multi-joint flexible robot for single-port laparoscopic surgery according to claim 1, characterized in that: The actuator arm (2) includes a flexible arm (2-1) and a rigid arm (2-2). The two ends of the flexible arm (2-1) are connected to the clamping mechanism (1) and the rigid arm (2-2) respectively. The flexible arm (2-1) includes a top joint (2-11), a reversing joint (2-12), a first joint group (2-13), and a second joint group (2-14). The top joint (2-11), the first joint group (2-13), the reversing joint (2-12), and the second joint group (2-14) are connected in series. The clamping mechanism (1) is fixedly connected to the top joint (2-11), and the second joint group (2-14) is connected to the rigid arm (2-2). The first joint (2-13) and the second joint (2-14) are respectively fixed with drive wires controlled by the yaw drive mechanism (3) to realize the bending movement of the first joint (2-13) and the second joint (2-14).

3. The multi-joint flexible robot for single-port laparoscopic surgery according to claim 2, characterized in that: The Both joint group one (2-13) and joint group two (2-14) contain multiple joints (A) with the same structure stacked together, and radial misalignment is limited by a drive wire. The deflection movement of adjacent joints (A) is accomplished by the relative sliding of the joint flange (A1) and the joint groove (A2).

4. The multi-joint flexible robot for single-port laparoscopic surgery according to claim 3, characterized in that: Eight through holes (A3) are evenly distributed on the peripheral side of each joint (A) to serve as channels for the drive wire. Each through hole (A3) is a variable diameter hole, including blind holes (A31) on both sides and a central hole (A32) that communicates with the blind holes. The diameter of the central hole (A32) is smaller than the inner diameter of the blind holes (A31).

5. The multi-joint flexible robot for single-port laparoscopic surgery according to claim 1, characterized in that: The yaw drive mechanism (3) includes a yaw drive motor (3-1), a lead screw pair (3-2), a front plate (3-3), a slider support (3-4), a guide rod (3-5), a frame one (3-6), a frame two (3-7), a drive wire retainer (3-8), a driver (3-9), and an internal gear ring (3-10). The front plate (3-3), frame one (3-6), and frame two (3-7) are arranged sequentially. Multiple guide rods (3-5) and eight sets of lead screw pairs (3-2) are arranged circumferentially between the front plate (3-3) and frame one (3-6). The two ends of the lead screw in each set of lead screw pairs (3-2) are rotatably mounted on the front plate (3-3) and frame one (3-6). Eight yaw drive motors (3-1) are fixed on frame one (3-6). The output end of each yaw drive motor (3-1) is connected to the corresponding lead screw. The drive screw holder (3-8) is fixedly connected to the slider support (3-4), and the slider support (3-4) is connected to the lead screw... The screw nut of the lever pair (3-2) is fixedly connected, the slider support (3-4) is slidably mounted on the guide rod (3-5), the front plate (3-3) is provided with the drive wire guide assembly (3-11), the drive wire guide assembly (3-11) is connected to the actuator arm (2), the first frame (3-6) is connected to the second frame (3-7), the front plate (3-3) and the second frame (3-7) are rotatably mounted on the rotary translation drive mechanism (4), the second frame (3-7) is provided with the driver (3-9) of the controllable yaw drive motor (3-1) and the internal gear ring (3-10) driven by the rotary translation drive mechanism (4).

6. The multi-joint flexible robot for single-port laparoscopic surgery according to claim 1, characterized in that: The rotation and translation drive mechanism (4) includes a bracket (4-1), a fixed base plate (4-2), a fixed slider (4-3), and a lead screw module (4-4). The yaw drive mechanism (3) is rotatably mounted on the bracket (4-1). The bracket (4-1) is provided with a drive assembly that can drive the internal gear ring (3-10) to rotate. The bracket (4-1) is mounted on the fixed base plate (4-2). The fixed slider (4-3) is threadedly connected to the lead screw module (4-4). The fixed base plate (4-2) is mounted on the fixed slider (4-3).

7. The multi-joint flexible robot for single-port laparoscopic surgery according to claim 5, characterized in that: The drive wire guide assembly (3-11) includes a front guide plate (3-111), a rear guide plate (3-112), a drive wire guide tube (3-113), and a guide support rod (3-114). The front guide plate (3-111) and the rear guide plate (3-112) are connected by the guide support rod (3-114) located between them. The rear guide plate is fixed to the front plate (3-3). The drive wire guide tube (3-113) is provided between the front guide plate (3-111) and the rear guide plate (3-112).

8. The multi-joint flexible robot for single-port laparoscopic surgery according to claim 5, characterized in that: The frame 1 (3-6) includes drive plate 1 (3-61) and drive plate 2 (3-62). Drive plate 1 (3-61) and drive plate 2 (3-62) are spaced apart and connected by bolts. A coupling (3-13) connecting the output end of the yaw drive motor (3-1) and the lead screw is arranged between them. The second frame (3-7) includes a third drive plate (3-71) and a rear plate (3-72). The third drive plate (3-71) and the rear plate (3-72) are spaced apart and connected by bolts. A driver (3-9) is arranged between them. An internal gear ring (3-10) is embedded in the middle of the rear plate (3-72). The drive wire guide assembly (3-11) and the third drive plate (3-71) are rotatably mounted on the rotary translation drive mechanism (4).

9. The multi-joint flexible robot for single-port laparoscopic surgery according to claim 6, characterized in that: The drive assembly includes a central shaft (4-5), a rotary drive motor (4-6), and gears (4-7). The central shaft (4-5) is fixed on the bracket (4-1). The yaw drive mechanism (3) is rotatably mounted on the bracket (4-1) and the central shaft (4-5). The rotary drive motor (4-6) is fixed on the bracket (4-1). A gear (4-7) is mounted on the output shaft of the rotary drive motor (4-6). The gear (4-7) meshes with the internal gear ring (3-10).

Images