Laparoscopic surgery robot and control method thereof

Abstract

The invention relates to the technical field of medical instruments, and particularly discloses a laparoscopic surgery robot and a control method thereof.The robot comprises a series arm, a parallel arm and a surgery end effector which are connected in sequence; the series arm comprises a first connecting arm, a moving arm, a first rotating joint, a second connecting arm, a second rotating joint, a third rotating joint, a third connecting arm and a fourth rotating joint which are connected in sequence. The method comprises the steps that the relation between dragging force and torque generated by the dragging force at all the joints, force / torque measured on all the joints and gravity balance torque of all the joints are obtained, the dragging force at a dragging point on the mechanical arm is determined, the robot is connected with three rotating joints and a fourth rotating joint in series, and the degree of freedom is high; the space required by conversion of various postures is small, and the motion range in an operation area is larger.

Description

Technical Field

[0001] The present invention relates to the technical field of medical instruments, and in particular to a laparoscopic surgical robot and a control method thereof. Background Art

[0002] The existing surgical robots include tandem arms, parallel arms and surgical instruments. The operator can drag the tandem arms to position them before the operation, so that the tandem arms are dragged to the required position before the operation. During the operation, the operator only needs to operate the parallel arms and surgical instruments to perform the operation. The tandem arms in the current surgical robots have a problem of insufficient range of motion, which makes it difficult to drag them to the required position before the operation. Summary of the invention

[0003] In order to solve the deficiencies in the prior art, the present invention provides a laparoscopic surgical robot and a control method thereof. The robot has a high degree of freedom by connecting three rotating joints that rotate vertically in sequence and a fourth rotating joint in series. The space required for switching between multiple postures is small, and the range of motion in the surgical area is larger.

[0004] To achieve the above object, the present invention adopts the following technical solution: On the one hand, the present invention provides a laparoscopic surgical robot, comprising a serial arm, a parallel arm and a surgical end effector connected in sequence, wherein the serial arm comprises a first connecting arm, a moving arm, a first rotating joint, a second connecting arm, a second rotating joint, a third rotating joint, a third connecting arm and a fourth rotating joint connected in sequence; The rotation axis of the first rotation joint is perpendicular to the vertical direction, the rotation axis of the second rotation joint is perpendicular to the rotation axis of the first rotation joint, and the rotation axis of the third rotation joint is perpendicular to the rotation axis of the second rotation joint.

[0005] In the present invention, the robot has a high degree of freedom by connecting three rotating joints that rotate vertically in sequence and a fourth rotating joint in series, and requires a small space for switching between various postures, and has a larger range of motion in the surgical area.

[0006] In a further technical solution, the parallel arm includes a static platform and a dynamic platform, the fourth rotation joint is connected to the static platform, and a line connecting a center point of the static platform and a center point of the dynamic platform is perpendicular to and intersects with the rotation axis of the fourth rotation joint, and the static platform and the third connecting arm are separated by a preset distance in the direction of the rotation axis of the fourth rotation joint.

[0007] The fourth rotation joint is connected to the side of the parallel arm, so that when the end effector is adjusted to the same angle, the movement range of the parallel arm of the technical solution is smaller.

[0008] In a further technical solution, the first rotation joint comprises a reducer, a bearing, a transmission assembly and a torque sensor connected in sequence, the torque sensor is connected to the second connecting arm, and the reducer is connected to the moving arm; The inner ring of the bearing is mounted on the transmission assembly, and the outer ring of the bearing is mounted on the second connecting arm or the torque sensor.

[0009] By arranging a bearing between the transmission assembly and the second connecting arm or the torque sensor, the bearing is subjected to the radial force generated by the deadweight of each connecting arm, thereby reducing the interference of the radial force on the measurement result of the torque sensor, making the torque measurement of the torque sensor more accurate.

[0010] In a further technical solution, the first rotational joint further includes a deformation member, the deformation member is connected between the transmission assembly and the torque sensor or between the torque sensor and the second connecting arm, and the deformation member is deformed in the direction of the bearing.

[0011] By setting a deformable part in the first rotational joint, when the first rotational joint is assembled, the accumulated error spacing between the parts caused by screw assembly can be compensated by the deformation of the deformable part, thereby greatly reducing the axial force borne by the torque sensor after the first rotational joint is assembled.

[0012] In a further technical solution, the deformable part is annular, and includes a first connecting part, a first deforming part and a second connecting part which are connected in sequence along the radial direction. The deformable part is respectively provided with a first annular groove and a second annular groove on opposite side surfaces in the axial direction, and a first deforming part is formed between the first annular groove and the second annular groove. The thickness of the first deforming part in the axial direction is less than the thickness of the first connecting part and the second connecting part.

[0013] The first deformation portion is formed by the first annular groove and the second annular groove. When subjected to an axial force, the relatively thin first deformation portion will be deformed to achieve the purpose of compensating for the accumulated error spacing.

[0014] In a further technical solution, the deformation member is located between the transmission assembly and the torque sensor.

[0015] The deformable parts utilize the original assembly gaps for assembly, and the overall structure is more compact.

[0016] In a further technical solution, the side of the first annular groove of the deformable member is disposed toward the bearing, the inner diameter of the first annular groove is smaller than the inner diameter of the second annular groove, the outer diameter of the first annular groove is smaller than the outer diameter of the second annular groove, and the outer diameter of the first annular groove is larger than the inner diameter of the second annular groove; The first connection portion is connected to the second connection arm, the second connection portion is connected to the outer ring of the torque sensor, and the plane where the first deformation portion is located has an angle with the force direction of the torque sensor.

[0017] The structural design of the first annular groove and the second annular groove makes it easier for the first deformation portion to deform toward the bearing.

[0018] In a further technical solution, the deformable part includes a third connecting part, a fourth connecting part, a second deformable part and a fifth connecting part which are connected in sequence along the radial direction. The deformable part is located on the side of the torque sensor away from the transmission assembly. The third connecting part is connected to the fourth connecting part to cover the torque sensor.

[0019] The design of the deformable part covering the torque sensor makes the deformable part have a larger volume and a larger deformable part, and the external deformable part is easier to assemble.

[0020] In a further technical solution, the third connecting portion is connected to the second connecting arm, the fifth connecting portion is connected to the inner ring of the torque sensor, the thickness of the fifth connecting portion in the axial direction is greater than the thickness of the third connecting portion in the axial direction, and the thickness of the third connecting portion in the axial direction is greater than the thickness of the second deformation portion in the axial direction; The third connection portion and the fifth connection portion are spaced apart in the axial direction, and the fourth connection portion is used to connect the third connection portion and the fifth connection portion in the axial direction.

[0021] The thickness of the third connecting part and the fifth connecting part ensures their respective connection strengths, while the second deformation part, which is relatively the thinnest, is more convenient for deformation.

[0022] In a further technical solution, the deformable member is annular, and comprises a sixth connecting portion, a third deformable portion and a seventh connecting portion which are connected in sequence; The sixth connection portion is connected to the transmission assembly, and the seventh connection portion is connected to the inner ring of the torque sensor.

[0023] The deformable member connected between the transmission assembly and the torque sensor has a smaller volume and a smaller axial dimension, and the overall structure is more compact.

[0024] In a further technical solution, the third deformation portion includes a first deformation body and a second deformation body sequentially connected in a radial direction, and the second deformation body is inclined toward the bearing.

[0025] The two deformation bodies form a deformation portion, and one of the deformation bodies is arranged to be inclined, so that the third deformation portion is more convenient to deform within a limited axial dimension.

[0026] In a further technical solution, an L-shaped seventh connecting member is provided on the seventh connecting portion, and a short side of the L-shape on the seventh connecting member is connected to the seventh connecting portion.

[0027] The L-shaped seventh connecting member can maximize the use of the gap between the transmission assembly and the torque sensor, increase the axial size of the deformable member, and increase the inclination angle of the second deformable body, making it easier to deform.

[0028] The beneficial effects are: 1. The robot of the present invention has three rotating joints that rotate vertically in sequence and one fourth rotating joint connected in series, so it has a high degree of freedom, requires a small space for switching between various postures, and has a larger range of motion in the surgical area.

[0029] 2. The fourth rotation joint is connected to the side of the parallel arm, so that when the end effector is adjusted to the same angle, the movement range of the parallel arm of the technical solution is smaller.

[0030] 3. By arranging a bearing between the transmission assembly and the second connecting arm or the torque sensor, the bearing is subjected to the radial force generated by the deadweight of each connecting arm, thereby reducing the interference of the radial force on the measurement result of the torque sensor, making the torque measurement of the torque sensor more accurate.

[0031] 4. By setting a deformable part in the first rotational joint, when the first rotational joint is assembled, the accumulated error spacing between the parts caused by screw assembly can be compensated by the deformation of the deformable part, thereby greatly reducing the axial force borne by the torque sensor after the first rotational joint is assembled.

[0032] 5. The first deformation portion is formed by the first annular groove and the second annular groove. When subjected to an axial force, the relatively thin first deformation portion will be deformed to achieve the purpose of compensating for the accumulated error spacing.

[0033] 6. The deformation parts utilize the original assembly gaps to assemble the deformation parts, making the overall structure more compact.

[0034] 7. The structural design of the first annular groove and the second annular groove makes it easier for the first deformation portion to deform toward the bearing.

[0035] 8. The design of the deformable part covering the torque sensor makes the deformable part have a larger volume and a larger deformable part, and the external deformable part is easier to assemble.

[0036] 9. The thickness of the third connecting part and the fifth connecting part ensures their respective connection strengths, while the relatively thinnest second deformation part is more convenient for deformation.

[0037] 10. The deformable part connected between the transmission assembly and the torque sensor has a smaller volume and smaller axial dimension, and the overall structure is more compact.

[0038] 11. Two deformation bodies form a deformation part, and one of the deformation bodies is inclined, so that the third deformation part is easier to deform within a limited axial size.

[0039] 12. The L-shaped seventh connecting member can maximize the use of the gap between the transmission assembly and the torque sensor, increase the axial size of the deformable member, and increase the inclination angle of the second deformable body, making it easier to deform. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a schematic diagram of the overall structure of a laparoscopic surgical robot according to an embodiment of the present invention; Figure 2 is a schematic structural diagram of a mechanical arm of a laparoscopic surgical robot according to an embodiment of the present invention; Figure 3 is a schematic diagram of the structure of the laparoscopic surgical robot after the second rotary joint in the mechanical arm of the robot is rotated according to an embodiment of the present invention; Figure 4 is a schematic diagram of the position of the fourth rotation joint of the mechanical arm of the laparoscopic surgical robot in an embodiment of the present invention before and after rotation; Figure 5 It is a schematic diagram of the position of the fourth rotating joint of the parallel arm connection method in the prior art before and after rotation; Figure 6 yes Figure 2 Sectional view at AA in the middle; Figure 7 yes Figure 6 The enlarged schematic diagram of point B in the middle; Figure 8 is a schematic diagram of the assembly of the deformable parts of the laparoscopic surgical robot according to the first embodiment of the present invention; Fig. 9 is a schematic structural diagram of a deformable member of a laparoscopic surgical robot according to a first embodiment of the present invention; Fig.10 is a schematic assembly diagram of a deformable part of a laparoscopic surgical robot according to a second embodiment of the present invention; Fig.11 is a schematic structural diagram of a deformable member of a laparoscopic surgical robot according to a second embodiment of the present invention; Fig.12 is a schematic diagram of the assembly of the deformation member of the laparoscopic surgical robot according to the third embodiment of the present invention; Fig.13 is a schematic structural diagram of a deformable member of a laparoscopic surgical robot according to a third embodiment of the present invention; Fig.14 is a schematic structural diagram of a single mechanical arm on a laparoscopic surgical robot according to an embodiment of the present invention; Fig.15 and Fig.16 is a schematic diagram of the structure of the coordinate system of each joint in the mechanical arm established in an embodiment of the present invention; Fig.17 It is a structural schematic diagram of dividing the robot arm into different components in an embodiment of the present invention.

[0041] Reference numerals: 11. base; 21. first connecting arm; 22. moving arm; 23. first rotating joint; 2301. second harmonic reducer; 2302. fourth transmission member; 2303. fifth transmission member; 2304. bearing stopper; 2305. second cross roller bearing; 2306. third deformation member; 23061. sixth connecting part; 23062. seventh connecting part; 23063. third deformation member; 23064. first deformation body; 23065. second deformation body; 23066. seventh connecting part; 2307. second torque sensor; 231. first harmonic reducer; 2311. second screw; 2312. third screw; 2313. first screw; 2314. third transmission member; 2315. second deformation member; 23151. third connecting part; 23152. fourth connecting part; 23153. second deformation part; 23154 , fifth connecting part; 232, first transmission member; 233, first cross roller bearing; 234, first deformation member; 2341, first connecting part; 2342, second annular groove; 2343, first deformation part; 2344, second connecting part; 2345, first annular groove; 2346, through hole; 235, second transmission member; 236, first torque sensor; 237, fifth screw; 238, fourth screw; 239, sixth screw; 2310, seventh screw; 24, second connecting arm; 25, second rotation joint; 26, third rotation joint; 27, third connecting arm; 28, fourth rotation joint; 29, parallel arm; 210, fifth rotation joint; 30, end effector; 401, first component; 402, second component; 403, third component; 404, fourth component; 405, fifth component; 406, sixth component. DETAILED DESCRIPTION

[0042] The present invention will be further described below in conjunction with the accompanying drawings: Example

[0043] The existing surgical robots include tandem arms, parallel arms and surgical instruments. The operator can drag the tandem arms to position them before the operation, so that the tandem arms are dragged to the required position before the operation. During the operation, the operator only needs to operate the parallel arms and surgical instruments to perform the operation. The tandem arms in the current surgical robots have a problem of insufficient range of motion, which makes it difficult to drag them to the required position before the operation.

[0044] To solve the problem of insufficient range of motion of the tandem arm in a surgical robot, this embodiment discloses a laparoscopic surgical robot, such as Figure 1 As shown, the robot includes multiple serial-parallel hybrid robotic arms. Figure 2 As shown, the robot arm includes a serial arm, a parallel arm 29 and a surgical end effector 30 connected in sequence, and the serial arm includes a first connecting arm 21, a moving arm 22, a first rotating joint 23, a second connecting arm 24, a second rotating joint 25, a third rotating joint 26, a third connecting arm 27, and a fourth rotating joint 28 connected in sequence; The robot also includes a base 11, which is connected to the end effector 30 through a first connecting arm 21, a moving arm 22, a first rotating joint 23, a second connecting arm 24, a second rotating joint 25, a third rotating joint 26, a third connecting arm 27, a fourth rotating joint 28, a parallel arm 29, and a fifth rotating joint 210 in sequence. The base 11 is connected to the first connecting arm 21 through a sixth rotating joint, and the sixth rotating joint drives the first connecting arm 21 to rotate relative to the base 11. The first connecting arm 21 is connected to the moving arm 22 through a moving joint, and the moving joint drives the moving arm to move on the first connecting arm 21. In this embodiment, the moving joint is a screw mechanism, which includes a screw and a screw nut that matches the screw thread. The screw nut is connected to the moving arm 22, and the moving arm 22 can be driven to move by the screw nut by driving the screw to rotate. A force sensor is connected between the screw nut and the moving moving arm 22, and the force sensor detects the force between the moving arm 22 and the screw nut.

[0045] The moving arm 22 slides on the side of the first connecting arm 21, the rotation axis of the first rotating joint 23 is perpendicular to the sliding surface of the moving arm 22, and the first end of the second connecting arm 24 is connected to the first rotating joint 23, so the second connecting arm 24 can rotate relative to the moving arm 22 along the rotation axis of the first rotating joint 23. The second rotating joint 25 is arranged at the second end of the second connecting arm 24, and the rotation axis of the second rotating joint 25 is parallel to the line connecting the first end and the second end of the second connecting arm 24. The third rotating joint 26 is connected to the second rotating joint 25, and the rotation axis of the third rotating joint 26 is parallel to the rotation axis of the fourth rotating joint 28.

[0046] The rotation axis of the first rotation joint 23 is perpendicular to the vertical direction, the rotation axis of the second rotation joint 25 is perpendicular to the rotation axis of the first rotation joint 23 , and the rotation axis of the third rotation joint 26 is perpendicular to the rotation axis of the second rotation joint 25 .

[0047] The first end of the third connecting arm 27 is connected to the third rotating joint 26, so the third connecting arm 27 can rotate relative to the second connecting arm 24 along the rotation axis of the third rotating joint 26. The second end of the third connecting arm 27 is connected to the fourth rotating joint 28, and the rotation axis of the fourth rotating joint 28 is perpendicular to the line connecting the first end and the second end of the third connecting arm 27, wherein the rotation axis of the fourth rotating joint 28 is parallel to the rotation axis of the third rotating joint 26. The parallel arm 29 is connected to the fourth rotating joint 28, so the parallel arm 29 can rotate relative to the third connecting arm 27 along the rotation axis of the fourth rotating joint 28.

[0048] like Figure 3 As shown, in the present invention, the robot has a high degree of freedom by connecting three rotating joints that rotate vertically in sequence and a fourth rotating joint in series, and requires a small space for switching between multiple postures, and has a larger range of motion in the surgical area.

[0049] In addition, existing surgical robots also have the problem that when working, the rotation axis of the surgical end effector is prone to approach or overlap with the rotation joint on the first connecting arm (i.e., the first rotation joint axis in this embodiment), resulting in a singularity point, which leads to abnormal control of the surgical end effector.

[0050] Therefore, if Figure 2 As shown, in this embodiment, the rotation axis of the first rotating joint 23 is perpendicular to the vertical direction (that is, the rotation axis of the first rotating joint 23 is parallel to the horizontal plane), the rotation axis of the second rotating joint 25 is perpendicular to the rotation axis of the first rotating joint 23, the rotation axis of the third rotating joint 26 is perpendicular to the rotation axis of the second rotating joint 25, and the surgical end effector and the first rotating joint 23 are staggered in the vertical direction (during the positioning process, the entire robotic arm is unfolded downward so that the surgical end effector 30 and the fifth rotating joint 210 move downward), so the rotation axis of the surgical end effector and the rotation axis of the first rotating joint 23 will not approach or overlap, and the rotation axis of the fifth rotating joint 210 and the rotation axis of the first rotating joint 23 will not approach or overlap.

[0051] In this embodiment, if Figure 6 and Figure 7 As shown, the first rotating joint 23 includes a reducer, a bearing, a transmission assembly and a first torque sensor 236 connected in sequence, the first torque sensor 236 is connected to the second connecting arm 24, and the reducer is connected to the moving arm 22; The inner ring of the bearing is mounted on the transmission assembly, and the outer ring of the bearing is mounted on the second connecting arm 24 .

[0052] In this embodiment, the reducer is a first harmonic reducer 231 .

[0053] In this embodiment, the bearing is a first cross roller bearing 233 .

[0054] By setting a bearing between the transmission assembly and the second connecting arm 24 or the first torque sensor 236, the bearing is subjected to the radial force generated by the deadweight of each connecting arm, thereby reducing the interference of the radial force on the measurement result of the first torque sensor 236, making the torque measurement of the first torque sensor 236 more accurate.

[0055] In this embodiment, if Figure 8 As shown, the first rotation joint 23 further includes a deformation member, which is connected between the first torque sensor 236 and the second connecting arm 24, and deforms toward the bearing.

[0056] By providing a deformable member in the first rotational joint 23, when the first rotational joint 23 is assembled, the accumulated error spacing between the parts caused by screw assembly can be compensated by the deformation of the deformable member, thereby greatly reducing the axial force on the torque sensor after the first rotational joint is assembled.

[0057] Specific as Figure 7 As shown, in this embodiment, the transmission assembly includes a first transmission member 232, a second transmission member 235, the deformable member is a first deformable member 234, the first harmonic reducer 231 is fixedly installed on the movable arm 22, the first harmonic reducer 231, the first transmission member 232, the second transmission member 235, and the first torque sensor 236 are arranged in sequence along the axial direction of the output shaft of the first harmonic reducer 231, and the first harmonic reducer 231, the first transmission member 232, the second transmission member 235, the first torque sensor 236, the first deformable member 234 and the second connecting arm 24 are connected in sequence, so the output shaft of the first harmonic reducer 231 transmits power to the second connecting arm 24 through the first transmission member 232, the second transmission member 235, the first torque sensor 236, and the first deformable member 234 in sequence.

[0058] The inner ring of the first cross roller bearing 233 is mounted on the first transmission member 232, and the second transmission member 235 is mounted on the first transmission member 232 to axially limit the inner ring of the first cross roller bearing 233 on the first transmission member 232. The outer ring of the first cross roller bearing 233 is mounted on the second connecting arm 24.

[0059] like Figure 7As shown, the first transmission member 232 is connected to the output shaft of the first harmonic reducer 231 through the first screw 2313, the inner ring of the first cross roller bearing 233 is connected to the second transmission member 235 through the second screw 2311, and the outer ring of the first cross roller bearing 233 is connected to the second connecting arm 24 through the third screw 2312. The second transmission member 235 is connected to the first transmission member 232 through the fourth screw 238, and the second transmission member 235 is connected to the first torque sensor 236 through the fifth screw 237. Among them, in the axial direction of the output shaft of the first harmonic reducer 231, the first deformation member 234 is located between the first torque sensor 236 and the second transmission member 235. It should be understood that the first deformation member 234 is not connected between the first torque sensor 236 and the second transmission member 235, but a through hole 2346 ( Fig. 9 As shown), the aperture of the through hole is larger than the diameter of the connection between the first torque sensor 236 and the second transmission member 235, the first deformable member 234 is connected to the first torque sensor 236 through the sixth screw 239, and the first deformable member 234 is connected to the second connecting arm 24 through the seventh screw 2310.

[0060] The deadweight of each connecting arm will generate radial force on the first rotating joint 23, and the radial force will interfere with the measurement result of the first torque sensor 236. Figure 7 As shown, in this embodiment, a first cross roller bearing 233 is arranged between the first transmission member 232 and the second connecting arm 24. The first cross roller bearing 233 can withstand the radial force generated by its own weight, thereby reducing the interference of the radial force on the measurement result of the first torque sensor 236.

[0061] In this embodiment, if Figure 8 and Fig. 9 As shown, the first deformable member 234 is annular, and includes a first connecting portion 2341, a first deformable portion 2343 and a second connecting portion 2344 which are sequentially connected in radial direction. The first deformable member 234 is respectively provided with a first annular groove 2345 and a second annular groove 2342 on two opposite side surfaces in the axial direction, that is, a first annular groove 2345 is provided on the side of the first deformable member 234 facing the second transmission member 235, and a second annular groove 2342 is provided on the side of the first deformable member 234 facing the first torque sensor 236, a first deformable portion 2343 is formed between the first annular groove 2345 and the second annular groove 2342, and the axial thickness of the first deformable portion 2343 is less than the thickness of the first connecting portion 2341 and the second connecting portion 2344.

[0062] The first deformation portion 2343 is formed by the first annular groove 2345 and the second annular groove 2342. When subjected to axial force, the relatively thin first deformation portion 2343 will deform toward the direction of the first cross roller bearing 233 to achieve the purpose of compensating for the accumulated error spacing.

[0063] In this embodiment, the first deformable member 234 is located between the second transmission member 235 and the first torque sensor 236 , which specifically refers to the spatial position of the first deformable member 234 rather than the connection relationship.

[0064] The first deformable member 234 utilizes the original assembly gap to assemble the first deformable member 234, and the overall structure is more compact. In this embodiment, the first deformable member 234 is provided with the side of the first annular groove 2345 facing the bearing, the inner diameter of the first annular groove 2345 is smaller than the inner diameter of the second annular groove 2342, the outer diameter of the first annular groove 2345 is smaller than the outer diameter of the second annular groove 2342, and the outer diameter of the first annular groove 2345 is larger than the inner diameter of the second annular groove 2342; The first connection portion 2341 is connected to the second connection arm 24 , the second connection portion 2344 is connected to the outer ring of the first torque sensor 236 , and the plane where the first deformation portion 2343 is located has an angle with the force direction of the first torque sensor 236 .

[0065] The structural design of the first annular groove 2345 and the second annular groove 2342 makes it easier for the first deformation portion 2343 to deform toward the bearing.

[0066] In another embodiment, if Fig.10 and Fig.11 As shown, the difference between this embodiment and the previous embodiment lies in that the shapes of the transmission assembly and the deformation member are different, and the arrangement method is different.

[0067] Specifically, in this embodiment, the transmission assembly includes a first transmission member 232 and a third transmission member 2314, the deformable member is a second deformable member 2315, and the first transmission member 232 is connected to the second connecting arm 24 via the third transmission member 2314, the first torque sensor 236, and the second deformable member 2315 in sequence.

[0068] In this embodiment, the second deformation member 2315 includes a third connection part 23151, a fourth connection part 23152, a second deformation part 23153 and a fifth connection part 23154 which are connected in sequence along the radial direction. The second deformation member 2315 is located on the side of the first torque sensor 236 away from the third transmission member 2314. The third connection part 23151 is connected to the fourth connection part 23152 to cover the first torque sensor 236.

[0069] The second deformable member 2315 is designed to cover the first torque sensor 236. The second deformable member 2315 has a larger volume and a larger deformable portion. The external second deformable member 2315 is easier to assemble.

[0070] In this embodiment, if Fig.10 As shown, the third connecting portion 23151 is connected to the second connecting arm 24, and the fifth connecting portion 23154 is connected to the inner ring of the first torque sensor 236, as shown in FIG. Fig.11 As shown, the thickness of the fifth connection portion 23154 in the axial direction is greater than the thickness of the third connection portion 23151 in the axial direction, and the thickness of the third connection portion 23151 in the axial direction is greater than the thickness of the second deformation portion 23153 in the axial direction; The third connection portion 23151 and the fifth connection portion 23154 are spaced apart from each other in the axial direction, and the fourth connection portion 23152 is used to connect the third connection portion 23151 and the fifth connection portion 23154 in the axial direction.

[0071] The thickness of the third connection portion 23151 and the fifth connection portion 23154 ensures their respective connection strengths, while the relatively thinnest second deformation portion 23153 is more convenient for deformation.

[0072] In another embodiment, if Fig.12 and Fig.13 As shown, the difference between this embodiment and the two previous embodiments is that the structure of the first rotating joint 23 is different, and the structure and arrangement of the deformable member are different. In this embodiment, the reducer is a second harmonic reducer 2301, the transmission assembly includes a fourth transmission member 2302 and a fifth transmission member 2303, the first rotating joint 23 also includes a bearing stopper 2304, the bearing is a second cross roller bearing 2305, the deformable member is a third deformable member 2306, and the torque sensor is a second torque sensor 2307, that is: The first rotating joint 23 includes a second harmonic reducer 2301, a fourth transmission member 2302, a fifth transmission member 2303, a bearing stopper 2304, a second cross roller bearing 2305, a third deformation member 2306, and a second torque sensor 2307. The second harmonic reducer 2301 is fixedly mounted on the moving arm 22, and the second harmonic reducer 2301, the fourth transmission member 2302, the fifth transmission member 2303, the third deformation member 2306, and the second torque sensor 2307 are sequentially arranged along the axial direction of the output shaft of the second harmonic reducer 2301.

[0073] The output shaft of the second harmonic reducer 2301 is connected in sequence through the fourth transmission member 2302, the fifth transmission member 2303, the third deformation member 2306, the second torque sensor 2307 and the second connecting arm 24, so the output shaft of the second harmonic reducer 2301 transmits power to the second connecting arm 24 through the fourth transmission member 2302, the fifth transmission member 2303, the third deformation member 2306 and the second torque sensor 2307 in sequence.

[0074] The inner ring of the second cross roller bearing 2305 is mounted on the fourth transmission member 2302 and the third deformation member 2306, and the fourth transmission member 2302 and the third deformation member 2306 are respectively provided with shaft shoulders to limit the inner ring of the second cross roller bearing 2305. The outer ring of the second cross roller bearing 2305 is mounted on the second torque sensor 2307 and the bearing stopper 2304, and the second torque sensor 2307 and the bearing stopper 2304 are respectively provided with shaft shoulders to limit the outer ring of the second cross roller bearing 2305.

[0075] like Fig.13 As shown, the third deformable member 2306 is annular, and includes a sixth connecting portion 23061, a third deformable portion 23063 and a seventh connecting portion 23062 which are connected in sequence; The sixth connection portion 23061 is connected to the fifth transmission member 2303 , and the seventh connection portion 23062 is connected to the inner ring of the second torque sensor 2307 .

[0076] Compared with the two aforementioned embodiments, the third deformation member 2306 connected between the fifth transmission member 2303 and the second torque sensor 2307 in this embodiment has a smaller volume and a smaller axial dimension, and the overall structure is more compact.

[0077] In this embodiment, if Fig.13 As shown, the third deformation portion 23063 includes a first deformation body 23064 and a second deformation body 23065 sequentially connected in the radial direction, and the second deformation body 23065 is inclined toward the bearing.

[0078] The two deformation bodies constitute the deformation portion, and one of the deformation bodies is inclined, so that the third deformation portion 23063 is easier to deform within a limited axial size.

[0079] In this embodiment, if Fig.13 As shown, an L-shaped seventh connecting member 23066 is disposed on the seventh connecting portion 23062 , and the short side of the L-shape on the seventh connecting member 23066 is connected to the seventh connecting portion 23062 .

[0080] The L-shaped seventh connecting member 23066 can maximize the use of the gap between the fifth transmission member 2303 and the second torque sensor 2307, increase the axial size of the third deformation member 2306, and increase the inclination angle of the second deformation body 23065, making it easier to deform.

[0081] In another embodiment, if Figure 3 As shown, the parallel arm 29 includes a static platform, a dynamic platform and three branches connecting the static platform and the dynamic platform, and the fourth rotation joint 28 is connected to the static platform. The line connecting the center point of the static platform and the center point of the dynamic platform is perpendicular and intersects with the rotation axis of the fourth rotation joint 28; the static platform and the third connecting arm 27 are separated by a preset distance in the direction of the rotation axis of the fourth rotation joint 28, and in this embodiment, the preset distance can be 100mm, 150mm or 200mm.

[0082] The fifth rotary joint 210 is connected to the moving platform in the parallel arm 29, and the rotation axis of the fifth rotary joint 210 is perpendicular to the moving platform. The end effector 30 is connected to the fifth rotary joint 210, and the end effector 30 can rotate relative to the moving platform along the rotation axis of the fifth rotary joint 210.

[0083] The fourth rotation joint 28 is connected to the side of the parallel arm 29, so that when the end effector 30 is adjusted to the same angle, the movement range of the parallel arm 29 of the present technical solution is smaller.

[0084] Specifically, contrast Figure 4 and Figure 5 It can be seen that Figure 5 This is an example of the fourth rotation joint 28 being connected to the top surface of the parallel arm 29 in the prior art. Figure 4 and Figure 5 In the embodiment, the swing angle of the end effector 30 is the same, but Figure 5 The swing amplitude of the parallel arm 29 is obviously greater than Figure 4 The swing amplitude of the parallel arm 29, that is, in the position adjustment before and after the operation, the robot of this embodiment requires a smaller movement space. The principle is that when the parallel arm 29 swings, the force arm when the rotation point is on its side is smaller than the force arm when the rotation point is on its end face.

[0085] In another embodiment, the above embodiments disclose various specific structural implementations of one of the serial-parallel hybrid robotic arms of the robot of the present invention and the first rotating joint in the serial-parallel hybrid robotic arm. It can be understood that the other rotating joints of the serial-parallel hybrid robotic arm of the robot in this embodiment have the same structure as the first rotating joint; the other serial-parallel hybrid robotic arms of the robot in this embodiment have the same structure as the serial-parallel hybrid robotic arm.

[0086] This embodiment also discloses a control method of the robot based on any of the above embodiments, the control method comprising the following steps: S1. Establish the coordinate system of each joint in the robotic arm; S2, establishing DH motion parameters between each joint coordinate system and the previous joint coordinate system of the joint according to each joint coordinate system in the robotic arm; S3, determining the transformation relationship between each joint coordinate system and the first joint coordinate system according to the DH motion parameters between each joint coordinate system and the previous joint coordinate system of the joint; S4, establishing DH motion parameters between the joint coordinate system of the first joint and the base coordinate system according to the joint coordinate systems in the robot arm; S5. Determine a conversion relationship between the joint coordinate system of the first joint and the base coordinate system according to a DH motion parameter between the joint coordinate system of the first joint and the base coordinate system; S6, obtaining the conversion relationship between each joint coordinate system and the first joint coordinate system, the conversion relationship between the joint coordinate system of the first joint and the base coordinate system, and determining the conversion relationship between each joint coordinate system and the base coordinate system; S7, obtaining the conversion relationship between the joint coordinate system and the base coordinate system, the position vector of each component in the robotic arm and the gravity of each component to determine the gravity balance torque of each joint; S8, obtaining the conversion relationship between the coordinate system of each joint and the base coordinate system, the position of the action point of the dragging force, and determining the relationship between the dragging force and the force / torque generated by the dragging force at each joint; S9. Obtain the relationship between the dragging force and the torque generated by the dragging force at each joint, the force / torque measured on each joint and the gravity balance torque of each joint, and determine the dragging force at the dragging point on the robotic arm.

[0087] Specifically, the structure of a single mechanical arm on the laparoscopic surgical robot in this embodiment is as follows: Fig.14 As shown, the parallel arm in the robot is Fig.14 It has been simplified to a cone barrel. Fig.14 It includes: the sixth rotating joint axis R1 in the vertical direction; the movable joint P1 in the horizontal direction; the first rotating joint axis R2 in the horizontal direction; the second rotating joint axis R3 in the vertical direction; the third rotating joint axis R4 in the horizontal direction; the fourth rotating joint axis R5 in the horizontal direction; the fifth rotating joint axis R6 in the vertical direction; and the rotating axis R7 inclined with the vertical direction (the rotating axis R7 is realized by the rotation of the surgical end effector along its axial direction).

[0088] The coordinate systems of each joint in the robot arm established in step S1 are as follows: Fig.15 and Fig.16As shown, the coordinates of each joint refer to the coordinate system where each joint is located. For the positive direction of the Z axis of each coordinate system, when the kinematic pair is a revolute pair, its positive direction of the Z axis conforms to the right-hand rule (the direction of rotation of the four fingers is the positive direction of rotation of the revolute pair, and the direction of the thumb is the positive direction of the Z axis); when the kinematic pair is a translation pair, its positive direction of the Z axis is the extension direction of the component. For the positive direction of the X axis of each coordinate system, when the Z axis of the current coordinate system is not parallel to the Z axis of the next coordinate system, its positive direction of the X axis is obtained by multiplying the Z axis of the current coordinate system by the Z axis of the next coordinate system; when the Z axis of the current coordinate system is parallel to the Z axis of the next coordinate system, its positive direction of the X axis points from the origin of the current coordinate system to the origin of the next coordinate system. The positive direction of the Y axis of each coordinate system conforms to the right-hand rule.

[0089] Specifically in Fig.15 and Fig.16 In the figure, coordinate system 1 is fixed to component 1, the origin R1 is located at the intersection of the axis of component ① (the sixth revolute joint) and the moving direction of component ② (the moving joint), the positive direction of the Z1 axis is vertically upward, the positive direction of the X1 axis is obtained by rotating the Z1 axis around the Z2 axis by 90°, and the positive direction of the Y1 axis conforms to the right-hand rule. Coordinate system 1 is the base coordinate system and also the coordinate system of the sixth revolute joint.

[0090] Coordinate system No. 2 is fixedly connected to component No. 2 (moving joint), and the origin L2 is located at the intersection of Z2 and Z3. The positive direction of the Z2 axis is the outward extension direction of component No. 2, the positive direction of the X2 axis is the cross product direction of Z2 and Z3, and the positive direction of the Y2 axis conforms to the right-hand rule. Coordinate system No. 2 is the moving joint coordinate system.

[0091] Coordinate system No. 3 is fixedly connected to component No. 3 (the first revolute joint), with its origin at R3. The positive direction of the Z3 axis is perpendicular to the paper and faces outward. The positive direction of the X3 axis is the cross product of Z3 and Z4. The positive direction of the Y3 axis conforms to the right-hand rule. Coordinate system No. 3 is the first revolute joint coordinate system.

[0092] Coordinate system No. 4 is fixedly connected to component No. 4 (the second revolute joint), and the origin R4 is located at the intersection of the axis of component No. 4 and the axis of component No. 5. The positive direction of the Z4 axis is vertically downward, the positive direction of the X4 axis is the same as the positive direction of the X3 axis, and the positive direction of the Y4 axis conforms to the right-hand rule. Coordinate system No. 4 is the second revolute joint coordinate system.

[0093] Coordinate system No. 5 is fixedly connected to component No. 5 (the third rotation joint). The origin R5 is located at the intersection of the common perpendicular line of components No. 5 and No. 6 and the axis of component No. 5. The positive direction of the Z5 axis is opposite to the positive direction of the Y4 axis. The positive direction of the X5 axis is the same as the positive direction of the X4 axis. The positive direction of the Y5 axis conforms to the right-hand rule. Coordinate system No. 5 is the coordinate system of the third rotation joint.

[0094] Coordinate system No. 6 is fixedly connected to component No. 6 (the fourth revolute joint). The origin R6 is located at the intersection of the common perpendicular line of components No. 6 and 7 and the axis of component No. 6. The positive direction of the Z6 axis is the same as the positive direction of the Z5 axis, the positive direction of the X6 axis is the same as the positive direction of the X5 axis, and the positive direction of the Y6 axis conforms to the right-hand rule. Coordinate system No. 6 is the coordinate system of the fourth revolute joint.

[0095] Coordinate system No. 7 is fixedly connected to component No. 7 (the fifth revolute joint), the origin R7 is located at the intersection of components No. 7 and No. 8, the positive direction of the Z7 axis is vertically downward, the positive direction of the X7 axis is opposite to the positive direction of the Z6 axis, and the positive direction of the Y7 axis conforms to the right-hand rule.

[0096] Coordinate system No. 8 is fixedly connected to component No. 8 (surgical end effector), the origin R8 coincides with R7, the positive direction of the Z8 axis is parallel to the axial direction of the surgical end effector, the positive direction of the X8 axis coincides with X7, and the positive direction of the Y8 axis conforms to the right-hand rule.

[0097] Coordinate system No. 9 is fixedly connected to component No. 9 (component No. 9 is virtual, and component No. 9 is equivalent to the end of the surgical end effector). The origin R9 is located at the end of the surgical end effector. The positive direction of Z9 is the same as the positive direction of Z8, the positive direction of X9 is the same as the positive direction of X8, and the positive direction of Y8 conforms to the right-hand rule.

[0098] The DH motion parameters between each joint coordinate system in the robotic arm established in step S2 and the previous joint coordinate system of the joint are as follows:

[0099] In the above table, 1, 2, 3, 4, 5, 6, 7, 8, and 9 represent the sixth joint coordinate system, the moving joint coordinate system, the first joint coordinate system, the second joint coordinate system, the third joint coordinate system, the fourth joint coordinate system, the fifth rotating joint coordinate system, the No. 8 coordinate system, and the No. 9 coordinate system, respectively.

[0100] Then in the above step S3, for a single joint coordinate system in the robot arm, the transformation matrix between each joint coordinate system and the previous joint coordinate system is , which can be expressed as:

[0101] Where i = 2, 3, 4, .... The transformation matrix from the coordinate system corresponding to the mth joint to the coordinate system corresponding to the nth joint , can be expressed by formula (2):

[0102] Using formulas (1-1) and (1-2), we can obtain the transformation matrix of each joint coordinate system relative to the first joint coordinate system: 1 i T, that is, determine the transformation relationship between each joint coordinate system and the base coordinate system.

[0103] The DH motion parameters between the joint coordinate system and the base coordinate system of the first joint established in S4 above are as follows:

[0104] In the above table, 0 and 1 represent the base coordinate system and the sixth joint coordinate system respectively.

[0105] Then, the above step S5 can determine the transformation matrix between the joint coordinate system of the first joint and the base coordinate system according to the DH motion parameters between the joint coordinate system of the first joint and the base coordinate system. 0 1 T, that is, to determine The transformation relationship between the joint coordinate system of the first joint and the base coordinate system.

[0106] The above step S6 can determine the conversion relationship between each joint coordinate system and the base coordinate system according to the conversion relationship between each joint coordinate system and the first joint coordinate system, and the conversion relationship between the joint coordinate system of the first joint and the base coordinate system. Then the conversion matrices of the sixth joint coordinate system, the moving joint coordinate system, the first joint coordinate system, the second joint coordinate system, the third joint coordinate system, and the fourth joint coordinate system relative to the base coordinate system are calculated as follows: .

[0107] According to Fig.17 The method shown divides a single robotic arm into different components, wherein the first connecting arm 21 and the movable arm 22 are divided into the first component 401, the first rotating joint 23 and the second connecting arm 24 are divided into the second component 402, the second rotating joint 25 is divided into the third component 403, the third rotating joint 26 is divided into the fourth component 404, the third connecting arm 27 and the fourth rotating joint 28 are divided into the fifth component 405, and the parallel arm and the surgical end effector are divided into the sixth component 406.

[0108] set up are the position vectors of the center of mass of the first component 401, the second component 402, the third component 403, the fourth component 404, the fifth component 405, and the sixth component 406 in coordinate systems 1, 2, 3, 4, 5, and 6 respectively; the center of mass of each component is expressed relative to its fixed coordinate system, such as the center of mass position of the first component 401 relative to its fixed coordinate system 1 is expressed as , so the centroid positions of the first component 401, the second component 402, the third component 403, the fourth component 404, the fifth component 405, and the sixth component 406 relative to their respective fixed coordinate systems are expressed as :

[0109] The centroid coordinates of each component relative to the coordinate system to which each component is fixed are And quality is a known quantity.

[0110] Using the coordinate transformation method, the 1st to 6th components are The gravity and the point of gravity are transferred to the joint to be solved In the fixed coordinate system j, the joint torque due to gravity can be solved by calculating the cross product of the position vector of the center of mass of each component and the gravity vector.

[0111] Considering the motion characteristics of the moving arm in the second component 402, it can only slide in the Z2 axis direction, so no torque is generated in the gravity direction. Based on this analysis, we regard the second component 402 as a rigid body and ignore the influence of its gravity torque in the calculation. In the subsequent calculation, the parallel arm and the surgical end effector are calculated as a rigid body.

[0112] The above step S7 specifically includes steps S71 to S74: According to the conversion relationship between each joint coordinate system and the base coordinate system, the position vector of each component in the robot arm and the gravity of each component, the principle of gravity balance torque of each joint is determined as follows: Assume that the coordinates of the centroid vector of each component in its fixed coordinate system are : .

[0113] Assume that the position vector of each center of mass is expressed in the base coordinate system as: .

[0114] The gravity balance torque of joint j can be solved: and .

[0115] The centroid position of each component in the coordinate system j is expressed as: ; The gravity of each component is expressed in coordinate system No. 1: ; Among them, E is the unit matrix, which is used to satisfy the calculation method of homogeneous coordinates and has no actual effect on the calculation results.

[0116] The gravity balance moment is obtained as: .

[0117] Step S71 , determining the gravity balance torque of the sixth revolute joint according to the conversion relationship between the sixth revolute joint coordinate system and the base coordinate system, the position vector of the first component 401 , and the gravity of the first component 401 .

[0118] Specifically, the gravity balance torque of the sixth revolute joint is solved as follows: .

[0119] The centroid position of each component in coordinate system No. 1 is expressed as follows: .

[0120] The gravity of each component is expressed in coordinate system No. 1: .

[0121] Gravity balance torque: .

[0122] Step S72 , determining the gravity balance moment of the first revolute joint according to the conversion relationship between the first revolute joint coordinate system and the base coordinate system, the position vector of the third component 403 , and the gravity of the third component 403 .

[0123] Specifically, the gravity balance torque of the first revolute joint is solved: .

[0124] The centroid position of each component in coordinate system No. 3 is expressed as follows: .

[0125] The gravity of each component is expressed in coordinate system 3: .

[0126] Gravity balance torque: .

[0127] Step S73 , determining the gravity balance moment of the second revolute joint according to the conversion relationship between the second revolute joint coordinate system and the base coordinate system, the position vector of the fourth component 404 , and the gravity of the fourth component 404 .

[0128] Specifically, the gravity balance torque of the second revolute joint is solved: .

[0129] The centroid position of each component in the No. 4 coordinate system is expressed as follows: .

[0130] The gravity of each component is expressed in coordinate system No. 4: .

[0131] Gravity balance torque: .

[0132] Step S74 , determining the gravity balance torque of the third revolute joint according to the conversion relationship between the third revolute joint coordinate system and the base coordinate system, the position vector of the fifth component 405 , and the gravity of the fifth component 405 .

[0133] Specifically, the gravity balance torque of the third revolute joint is solved: .

[0134] The centroid position of each component in coordinate system No. 5 is expressed as follows: .

[0135] The gravity of each component is expressed in coordinate system No. 5: .

[0136] Gravity balance torque: .

[0137] Step S75 , determining the gravity balance torque of the fourth revolute joint according to the conversion relationship between the fourth revolute joint coordinate system and the base coordinate system, the position vector of the sixth component 406 , and the gravity of the sixth component 406 .

[0138] Specifically, the gravity balance torque of the fourth revolute joint is solved: .

[0139] The centroid position of each component in the No. 6 coordinate system is expressed as follows: .

[0140] The gravity of each component is expressed in coordinate system 6: .

[0141] Gravity balance torque: .

[0142] The above step S7 calculates the gravity balance torque of each joint. Before the operation, the doctor or the doctor's assistant needs to drag the robotic arm to position it so that the robotic arm is dragged to the required position before the operation, so the magnitude of the dragging force applied to the robotic arm needs to be calculated; the above step S8 specifically includes steps S81 to S86: The principle of solving the drag force / torque of joint j is as follows: Assuming that the position of the drag force acting on the drag point on the sixth component 406 is known, the description of the acting point in the coordinate system No. 6 is : .

[0143] Assume that the dragging force at the dragging point is F, and the description of F in the No. 6 coordinate system is : .

[0144] The description of the drag force action point in the base coordinate system is: .

[0145] The description of the drag force in the base coordinate system is: .

[0146] The drag torque of joint j can be solved by the following steps: The description of the drag force action point in coordinate system j is: .

[0147] The description of the drag force in coordinate system j is: .

[0148] The torque generated by the drag force at joint j is: .

[0149] Step S81, determining the relationship between the dragging force and the torque generated by the dragging force at the sixth revolving joint according to the conversion relationship between the sixth revolving joint coordinate system and the base coordinate system and the position of the action point of the dragging force.

[0150] Specifically, the drag torque of the sixth revolute joint is solved as follows: The description of the drag force action point in coordinate system 1 is: .

[0151] The description of the drag force in coordinate system 1 is: .

[0152] The torque generated by the drag force at the sixth revolute joint is: .

[0153] Step S81 is to use the dragging force F0 to represent the torque generated by the dragging force at the sixth revolute joint, so as to facilitate the subsequent equation (1-4) to solve the dragging force F0 by using the elimination method.

[0154] Step S82: Determine the relationship between the dragging force and the force generated by the dragging force at the moving joint according to the conversion relationship between the moving joint coordinate system and the base coordinate system and the position of the action point of the dragging force.

[0155] Specifically, the drag force of the moving joint is solved: The description of the drag force action point in coordinate system 2 is: .

[0156] The description of the drag force in coordinate system 2 is: .

[0157] The force generated by the drag force at joint 2 is: .

[0158] Step S82 is to use the dragging force F0 to represent the force generated at the moving joint, so as to facilitate the subsequent equation (1-4) to solve the dragging force F0 by using the elimination method.

[0159] Step S83: Determine the relationship between the dragging force and the torque generated by the dragging force at the first rotational joint according to the conversion relationship between the first rotational joint coordinate system and the base coordinate system and the position of the action point of the dragging force.

[0160] Specifically, the drag torque of the first rotational joint is solved: The description of the drag force action point in coordinate system 3 is: .

[0161] The description of the drag force in coordinate system 3 is: .

[0162] The torque generated by the drag force at joint 3 is: .

[0163] Step S83 is to use the dragging force F0 to represent the torque generated by the dragging force at the first rotational joint, so as to facilitate the subsequent equation (1-4) to solve the dragging force F0 by using the elimination method.

[0164] Step S84: Determine the relationship between the dragging force and the torque generated by the dragging force at the second rotational joint according to the conversion relationship between the second rotational joint coordinate system and the base coordinate system and the position of the action point of the dragging force.

[0165] Specifically, the drag torque of the second rotational joint is solved: The description of the drag force action point in coordinate system No. 4 is: .

[0166] The description of the drag force in coordinate system No. 4 is: .

[0167] The torque generated by the drag force at joint 4 is: .

[0168] Step S84 is to use the dragging force F0 to represent the torque generated by the dragging force at the second revolute joint, so as to facilitate solving the dragging force F0 in the subsequent equations (1-4) by the elimination method.

[0169] Step S85: Determine the relationship between the dragging force and the torque generated by the dragging force at the third rotational joint according to the conversion relationship between the third rotational joint coordinate system and the base coordinate system and the position of the action point of the dragging force.

[0170] Specifically, the drag torque of the third rotational joint is solved: The description of the drag force action point in coordinate system No. 5 is: .

[0171] The description of the drag force in coordinate system No. 5 is: .

[0172] The torque generated by the drag force at joint 5 is: .

[0173] Step S85 is to use the dragging force F0 to represent the torque generated by the dragging force at the third rotational joint, so as to facilitate the subsequent equation (1-4) to solve the dragging force F0 by using the elimination method.

[0174] Step S86: Determine the relationship between the dragging force and the torque generated by the dragging force at the fourth rotational joint according to the conversion relationship between the fourth rotational joint coordinate system and the base coordinate system and the position of the action point of the dragging force.

[0175] Specifically, the drag torque of the fourth rotational joint is solved: The description of the drag force action point in coordinate system No. 6 is: .

[0176] The description of the drag force in coordinate system 6 is: .

[0177] The torque generated by the drag force at joint 6 is: .

[0178] Step S86 is to use the dragging force F0 to represent the torque generated by the dragging force at the fourth rotational joint, so as to facilitate the subsequent equation (1-4) to solve the dragging force F0 by using the elimination method.

[0179] The specific principle of the above step S9 is: a force sensor / torque sensor is installed on each joint, and the force / torque value of each joint can be obtained according to the force sensor / torque sensor installed at each joint, and the torque measured on the sixth rotation joint, the force measured on the moving joint, the torque measured on the first rotation joint, the torque measured on the second rotation joint, the torque measured on the third rotation joint, and the torque measured on the fourth rotation joint are obtained in sequence: .according to: The torque measured by the force / torque sensor = the gravity balance torque on each joint + the drag torque generated by the drag force on each joint; Then the following equation can be established:

[0180] Among them, F p1 is the force measured by the force sensor on the moving joint. Select any three equations from the above equation group and solve them by elimination method to obtain the dragging force at the dragging point. .

[0181] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A laparoscopic surgical robot, characterized in that: It includes a serial arm, a parallel arm and a surgical end effector connected in sequence, wherein the serial arm includes a first connecting arm, a moving arm, a first rotating joint, a second connecting arm, a second rotating joint, a third rotating joint, a third connecting arm and a fourth rotating joint connected in sequence; The rotation axis of the first rotation joint is perpendicular to the vertical direction, the rotation axis of the second rotation joint is perpendicular to the rotation axis of the first rotation joint, and the rotation axis of the third rotation joint is perpendicular to the rotation axis of the second rotation joint.

2. The robot according to claim 1, characterized in that: The parallel arm includes a static platform and a dynamic platform, the fourth rotation joint is connected to the static platform, and a line connecting a center point of the static platform and a center point of the dynamic platform is perpendicular to and intersects with a rotation axis of the fourth rotation joint, and the static platform and the third connecting arm are spaced apart by a preset distance in the direction of the rotation axis of the fourth rotation joint.

3. The robot according to claim 1 or 2, characterized in that: The first rotating joint comprises a reducer, a bearing, a transmission assembly and a torque sensor connected in sequence, the torque sensor is connected to the second connecting arm, and the reducer is connected to the moving arm; The inner ring of the bearing is mounted on the transmission assembly, and the outer ring of the bearing is mounted on the second connecting arm or the torque sensor.

4. The robot according to claim 3, characterized in that: The first rotation joint further includes a deformation member, which is connected between the transmission assembly and the torque sensor or between the torque sensor and the second connecting arm, and the deformation member is deformed in the direction of the bearing.

5. The robot according to claim 4, characterized in that: The deformable member is annular, and includes a first connecting portion, a first deforming portion, and a second connecting portion which are sequentially connected in a radial direction. The deformable member is provided with a first annular groove and a second annular groove on opposite side surfaces in an axial direction, respectively. A first deforming portion is formed between the first annular groove and the second annular groove. The thickness of the first deforming portion in the axial direction is less than the thickness of the first connecting portion and the second connecting portion.

6. The robot according to claim 5, characterized in that: The deformation member is located between the transmission assembly and the torque sensor.

7. The robot according to claim 6, characterized in that: The deformable member is provided with a first annular groove whose side faces the bearing, the inner diameter of the first annular groove is smaller than the inner diameter of the second annular groove, the outer diameter of the first annular groove is smaller than the outer diameter of the second annular groove, and the outer diameter of the first annular groove is larger than the inner diameter of the second annular groove; The first connection portion is connected to the second connection arm, the second connection portion is connected to the outer ring of the torque sensor, and the plane where the first deformation portion is located has an angle with the force direction of the torque sensor.

8. The robot according to claim 4, characterized in that: The deformable member includes a third connecting portion, a fourth connecting portion, a second deformable portion and a fifth connecting portion which are sequentially connected in radial direction. The deformable member is located on the side of the torque sensor away from the transmission assembly. The third connecting portion is connected to the fourth connecting portion to cover the torque sensor.

9. The robot according to claim 8, characterized in that: The third connection portion is connected to the second connection arm, the fifth connection portion is connected to the inner ring of the torque sensor, the thickness of the fifth connection portion in the axial direction is greater than the thickness of the third connection portion in the axial direction, and the thickness of the third connection portion in the axial direction is greater than the thickness of the second deformation portion in the axial direction; The third connection portion and the fifth connection portion are spaced apart in the axial direction, and the fourth connection portion is used to connect the third connection portion and the fifth connection portion in the axial direction.

10. The robot according to claim 4, characterized in that: The deformable member is annular, and comprises a sixth connecting portion, a third deformable portion and a seventh connecting portion which are connected in sequence; The sixth connection portion is connected to the transmission assembly, and the seventh connection portion is connected to the inner ring of the torque sensor.

11. The robot according to claim 10, characterized in that: The third deformation portion includes a first deformation body and a second deformation body sequentially connected in a radial direction, and the second deformation body is inclined toward the bearing.

12. The robot according to claim 11, characterized in that: The seventh connection portion is provided with an L-shaped seventh connection piece, and the short side of the L-shape on the seventh connection piece is connected to the seventh connection portion.

13. A control method of a robot according to any one of claims 1 to 12, characterized in that: The following steps are involved: Obtain the conversion relationship between each joint coordinate system and the first joint coordinate system, the conversion relationship between the joint coordinate system of the first joint and the base coordinate system, and determine the conversion relationship between each joint coordinate system and the base coordinate system; Obtaining the conversion relationship between the joint coordinate system and the base coordinate system, the position vector of each component in the robotic arm and the gravity of each component to determine the gravity balance torque of each joint; Obtaining the conversion relationship between the coordinate systems of each joint and the base coordinate system, the position of the point of action of the dragging force, and determining the relationship between the dragging force and the force / torque generated by the dragging force at each joint; The relationship between the dragging force and the torque generated by the dragging force at each joint, the force / torque measured on each joint and the gravity balance torque of each joint are obtained to determine the dragging force at the dragging point on the robot arm.

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