A laparoscopic surgical robot and its control method

Abstract

The present invention relates to the technical field of medical devices, and specifically discloses a laparoscopic surgical robot and a control method thereof. The robot includes a serial arm, a parallel arm, and a surgical end effector that are connected in sequence. 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 that are connected in sequence. The method includes obtaining 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 determining the dragging force at the dragging point on the robotic arm. The robot has a high degree of freedom by connecting three rotating joints that rotate vertically in sequence and a fourth rotating joint, requires a small space for the conversion of various postures, and has a larger movement range in the surgical area.

Description

Technical Field

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

[0002] Currently, existing surgical robots include serial arms, parallel arms and surgical instruments. The operator can drag the serial arm to position it before the operation, so that the serial arm is dragged to the required position before the operation. During the operation, the operator only needs to operate the parallel arm and the surgical instruments to perform the operation. At present, the serial arm in the surgical robot has the problem of insufficient movement range, resulting in difficulty in dragging it to the required position before the operation. Summary of the Invention

[0003] 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 rotation joints that rotate vertically in sequence and a fourth rotation joint, requires less space for various posture conversions, and has a larger movement range in the surgical area.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] On the one hand, the present invention provides a laparoscopic surgical robot, including a serial arm, a parallel arm and a surgical end effector connected in sequence. The serial arm includes a first connecting arm, a moving arm, a first rotation joint, a second connecting arm, a second rotation joint, a third rotation joint, a third connecting arm and a fourth rotation joint connected in sequence;

[0006] 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.

[0007] In the present invention, the robot has a high degree of freedom by connecting three rotation joints that rotate vertically in sequence and a fourth rotation joint, requires less space for various posture conversions, and has a larger movement range in the surgical area.

[0008] In a further technical solution, the parallel arm includes a static platform and a moving platform. The fourth rotation joint is connected to the static platform, and the connection line between the center point of the static platform and the center point of the moving platform is perpendicular to and intersects the rotation axis of the fourth rotation joint. 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.

[0009] The fourth rotation joint is connected to the side of the parallel arm, so that in the case of adjusting the same angle of the end effector, the movement amplitude of the parallel arm in this technical solution is smaller.

[0010] In a further technical solution, the first rotating joint includes a speed reducer, a bearing, a transmission component, and a torque sensor connected in sequence. The torque sensor is connected to the second connecting arm, and the speed reducer is connected to the moving arm;

[0011] The inner ring of the bearing is mounted on the transmission component, and the outer ring of the bearing is mounted on the second connecting arm or the torque sensor.

[0012] By arranging a bearing between the transmission component and the second connecting arm or the torque sensor, the bearing bears the radial force generated by the self-weight of each connecting arm, thereby reducing the interference of this radial force on the measurement result of the torque sensor and making the torque measurement of the torque sensor more accurate.

[0013] In a further technical solution, the first rotating joint further includes a deformable member. The deformable member is connected between the transmission component and the torque sensor or between the torque sensor and the second connecting arm, and the deformable member deforms in the direction towards the bearing.

[0014] By arranging a deformable member in the first rotating joint, when the first rotating joint is assembled, the cumulative error spacing generated by screw assembly between each part can be compensated by the deformation of the deformable member, thereby greatly reducing the axial force borne by the torque sensor after the first rotating joint is assembled.

[0015] In a further technical solution, the deformable member is annular. The deformable member includes a first connecting portion, a first deformable portion, and a second connecting portion connected in sequence along the radial direction. First annular grooves and second annular grooves are respectively provided on opposite side surfaces of the deformable member in the axial direction. A first deformable portion is formed between the first annular groove and the second annular groove, and the thickness of the first deformable portion in the axial direction is less than the thicknesses of the first connecting portion and the second connecting portion.

[0016] The first deformable portion is formed by the first annular groove and the second annular groove. When subjected to an axial force, the relatively thin first deformable portion will deform to achieve the purpose of compensating for the cumulative error spacing.

[0017] In a further technical solution, the deformable member is located between the transmission component and the torque sensor.

[0018] The deformable member utilizes the original assembly gap for the assembly of the deformable member, and the overall structure is more compact.

[0019] In a further technical solution, the side surface of the deformable member provided with the first annular groove faces the bearing. The inner diameter of the first annular groove is less than the inner diameter of the second annular groove, the outer diameter of the first annular groove is less than the outer diameter of the second annular groove, and the outer diameter of the first annular groove is greater than the inner diameter of the second annular groove;

[0020] The first connecting portion is connected to the second connecting arm, the second connecting portion is connected to the outer ring of the torque sensor, and the plane where the first deformation portion is located forms an angle with the force application direction of the torque sensor.

[0021] The structural design of the first annular groove and the second annular groove makes it more convenient for the first deformation portion to deform towards the bearing.

[0022] In a further technical solution, the deformable member includes a third connecting portion, a fourth connecting portion, a second deformation portion, and a fifth connecting portion that are sequentially connected in the radial direction. The deformable member is located on the side of the torque sensor away from the transmission assembly, and the third connecting portion is connected to the fourth connecting portion to wrap the torque sensor.

[0023] With the design that the deformable member wraps the torque sensor, the deformable member has a larger volume, and thus has a larger deformable part, and the external deformable member is more convenient for assembly.

[0024] 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;

[0025] The third connecting portion and the fifth connecting portion are spaced apart in the axial direction, and the fourth connecting portion is used to connect the third connecting portion and the fifth connecting portion in the axial direction.

[0026] The thicknesses of the third connecting portion and the fifth connecting portion ensure their respective connection strengths, and at the same time, they are more convenient for deformation compared to the thinnest second deformation portion.

[0027] In a further technical solution, the deformable member is annular, and the deformable member includes a sixth connecting portion, a third deformation portion, and a seventh connecting portion that are sequentially connected;

[0028] The sixth connecting portion is connected to the transmission assembly, and the seventh connecting portion is connected to the inner ring of the torque sensor.

[0029] 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.

[0030] In a further technical solution, the third deformation portion includes a first deformable body and a second deformable body that are sequentially connected in the radial direction, and the second deformable body is inclined towards the bearing.

[0031] The two deformable bodies form a deformation portion, and at the same time, one of the deformable bodies is set to be inclined, so that in the limited axial dimension, the third deformation portion is more convenient for deformation.

[0032] In a further technical solution, an L-shaped seventh connecting member is provided on the seventh connecting portion, and the short side of the L shape on the seventh connecting member is connected to the seventh connecting portion.

[0033] Setting the L-shaped seventh connecting member can maximize the utilization of the gap between the transmission component and the torque sensor, increase the axial dimension of the deformable member, increase the inclination angle of the second deformable body, and make it more convenient for deformation.

[0034] The beneficial effects are as follows:

[0035] 1. The robot of the present invention has a high degree of freedom by serially connecting three rotation joints that rotate vertically in sequence and a fourth rotation joint, requires a small space for converting various postures, and has a larger movement range in the surgical area.

[0036] 2. The fourth rotation joint is connected to the side of the parallel arm, so that when the end effector is adjusted by the same angle, the movement amplitude of the parallel arm in this technical solution is smaller.

[0037] 3. By arranging a bearing between the transmission component and the second connecting arm or the torque sensor, the bearing bears the radial force generated by the self-weight of each connecting arm, thereby reducing the interference of the radial force on the measurement result of the torque sensor and making the torque measurement of the torque sensor more accurate.

[0038] 4. By arranging a deformable member in the first rotation joint, when the first rotation joint is assembled, the error spacing accumulation generated by screw assembly between each part can be compensated by the deformation of the deformable member, thereby greatly reducing the axial force borne by the torque sensor after the first rotation joint is assembled.

[0039] 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 deform to achieve the purpose of compensating for the error spacing accumulation.

[0040] 6. The deformable member utilizes the original assembly gap for the assembly of the deformable member, and the overall structure is more compact.

[0041] 7. The structural design of the first annular groove and the second annular groove makes the first deformation portion more convenient to deform towards the bearing.

[0042] 8. With the design that the deformable member covers the torque sensor, the deformable member has a larger volume, and thus has a larger deformable part, and the external deformable member is more convenient for assembly.

[0043] 9. The thickness of the third connecting portion and the fifth connecting portion ensures their respective connection strengths, and at the same time is more convenient for deformation compared to the thinnest second deformation portion.

[0044] 10. The deformable member connected between the transmission assembly and the torque sensor has a smaller volume and smaller axial dimension, and the overall structure is more compact.

[0045] 11. Two deformable bodies form a deformable part. At the same time, one of the deformable bodies is set to be inclined, so that in the limited axial dimension, the third deformable part is more convenient for deformation.

[0046] 12. Setting the L-shaped seventh connecting member can maximize the utilization of the gap between the transmission assembly and the torque sensor, increase the axial dimension of the deformable member, and increase the inclination angle of the second deformable body, making it more convenient for deformation. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 is a schematic diagram of the overall structure of the laparoscopic surgical robot according to an embodiment of the present invention;

[0048] Figure 2 is a schematic diagram of the structure of the robotic arm of the laparoscopic surgical robot according to an embodiment of the present invention;

[0049] Figure 3 is a schematic diagram of the structure of the robotic arm of the laparoscopic surgical robot according to an embodiment of the present invention after the second rotating joint rotates;

[0050] Figure 4 is a schematic diagram of the positions of the robotic arm of the laparoscopic surgical robot according to an embodiment of the present invention before and after the fourth rotating joint rotates;

[0051] Figure 5 is a schematic diagram of the positions of the fourth rotating joint of the parallel arm connection method in the prior art before and after rotation;

[0052] Figure 6 is Figure 2 a cross-sectional view taken along line A-A in

[0053] Figure 7 is Figure 6 an enlarged schematic view of B in

[0054] Figure 8 is an assembly schematic diagram of the deformable member of the laparoscopic surgical robot according to the first embodiment of the present invention;

[0055] Figure 9 is a schematic diagram of the structure of the deformable member of the laparoscopic surgical robot according to the first embodiment of the present invention;

[0056] Figure 10 is an assembly schematic diagram of the deformable member of the laparoscopic surgical robot according to the second embodiment of the present invention;

[0057] Figure 11 is a schematic diagram of the structure of the deformable member of the laparoscopic surgical robot according to the second embodiment of the present invention;

[0058] Figure 12 It is an assembly schematic diagram of a deformed part of a laparoscopic surgical robot according to the third embodiment of the present invention;

[0059] Figure 13 It is a structural schematic diagram of a deformed part of a laparoscopic surgical robot according to the third embodiment of the present invention;

[0060] Figure 14 It is a structural schematic diagram of a single robotic arm on the laparoscopic surgical robot according to the embodiment of the present invention;

[0061] Figure 15 and Figure 16 It is a structural schematic diagram of each joint coordinate system in the robotic arm established in the embodiment of the present invention;

[0062] Figure 17 It is a structural schematic diagram of dividing the robotic arm into different components in the embodiment of the present invention.

[0063] Reference numerals:

[0064] 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 limiting member; 2305, second crossed roller bearing; 2306, third deformed part; 23061, sixth connecting part; 23062, seventh connecting part; 23063, third deformed part; 23064, first deformed body; 23065, second deformed body; 23066, seventh connecting member; 2307, second torque sensor; 231, first harmonic reducer; 2311, second screw; 2312, third screw; 2313, first screw; 2314, third transmission member; 2315, second deformed part; 23151, third connecting part; 23152, fourth connecting part; 23153, second deformed part; 23154, fifth connecting part; 232, first transmission member; 233, first crossed roller bearing; 234, first deformed part; 2341, first connecting part; 2342, second annular groove; 2343, first deformed 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 rotating joint; 26, third rotating joint; 27, third connecting arm; 28, fourth rotating joint; 29, parallel arm; 210, fifth rotating joint; 30, end effector; 401, first component; 402, second component; 403, third component; 404, fourth component; 405, fifth component; 406, sixth component. Detailed implementation manners

[0065] The present invention will be further described below with reference to the accompanying drawings:

[0066] Embodiment

[0067] Currently, existing surgical robots include serial arms, parallel arms and surgical instruments. The operator can drag the serial arm to position it before the operation, so that the serial arm is dragged to the required position before the operation. During the operation, the operator only needs to operate the parallel arm and the surgical instrument to perform the operation. At present, the serial arm in the surgical robot has the problem of insufficient movement range, resulting in difficulty in dragging it to the required position before the operation.

[0068] To solve the problem of insufficient movement range of the serial arm in the surgical robot, this embodiment discloses a laparoscopic surgical robot, as Figure 1 shown. The robot includes a plurality of series-parallel hybrid robotic arms. As Figure 2 shown, the robotic arm includes a serial arm, a parallel arm 29 and a surgical end effector 30 connected in sequence. 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;

[0069] The robot further includes a base 11. The base 11 is connected to the end effector 30 through the first connecting arm 21, the moving arm 22, the first rotating joint 23, the second connecting arm 24, the second rotating joint 25, the third rotating joint 26, the third connecting arm 27, the fourth rotating joint 28, the parallel arm 29, and the fifth rotating joint 210 in sequence. Among them, the base 11 and the first connecting arm 21 are connected 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 and the moving arm 22 are connected 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 lead screw mechanism. The lead screw mechanism includes a lead screw and a lead screw nut that is threadedly engaged with the lead screw. The lead screw nut is connected to the moving arm 22. Then, by driving the lead screw to rotate, the moving arm 22 can be driven to move through the lead screw nut. Among them, a force sensor is connected between the lead screw nut and the moving arm 22, and the force sensor detects the force between the moving arm 22 and the lead screw nut.

[0070] 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. The first end of the second connecting arm 24 is connected to the first rotating joint 23. Then, 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. The rotation axis of the second rotating joint 25 is parallel to the line connecting the first end and the second end on the second connecting arm 24. The third rotating joint 26 is connected to the second rotating joint 25. The rotation axis of the third rotating joint 26 is parallel to the rotation axis of the fourth rotating joint 28.

[0071] The rotation axis of the first rotating joint 23 is perpendicular to the vertical direction. The rotation axis of the second rotating joint 25 is perpendicular to the rotation axis of the first rotating joint 23. And the rotation axis of the third rotating joint 26 is perpendicular to the rotation axis of the second rotating joint 25.

[0072] The first end of the third connecting arm 27 is connected to the third rotating joint 26. Then, 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. The rotation axis of the fourth rotating joint 28 is perpendicular to the line connecting the first end and the second end on 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. Then, the parallel arm 29 can rotate relative to the third connecting arm 27 along the rotation axis of the fourth rotating joint 28.

[0073] As Figure 3 shown, in the present invention, the robot has a high degree of freedom by connecting three rotating joints that rotate perpendicular to each other in sequence and a fourth rotating joint. The space required for the conversion of various postures is small, and the movement range in the surgical area is larger.

[0074] In addition, there is also a problem with existing surgical robots that when working, it is easy to have a singularity problem where the rotation axis of the surgical end effector approaches or coincides with the rotating joint on the first connecting arm (i.e., the axis of the first rotating joint in this embodiment), resulting in abnormal control of the surgical end effector.

[0075] Therefore, as Figure 2As shown, in this embodiment, by setting the rotation axis of the first rotating joint 23 perpendicular to the vertical direction (i.e., the rotation axis of the first rotating joint 23 is parallel to the horizontal plane), the rotation axis of the second rotating joint 25 perpendicular to the rotation axis of the first rotating joint 23, and the rotation axis of the third rotating joint 26 perpendicular to the rotation axis of the second rotating joint 25, and the surgical end effector is arranged offset from the first rotating joint 23 in the vertical direction (during the positioning process, the entire robotic arm unfolds downward so that the surgical end effector 30 and the fifth rotating joint 210 move downward). Therefore, the rotation axis of the surgical end effector and the rotation axis of the first rotating joint 23 will not approach or coincide, and the rotation axis of the fifth rotating joint 210 and the rotation axis of the first rotating joint 23 will not approach or coincide either.

[0076] In this embodiment, as Figure 6 and Figure 7 shown, the first rotating joint 23 includes a speed reducer, a bearing, a transmission component, and a first torque sensor 236 connected in sequence. The first torque sensor 236 is connected to the second connecting arm 24, and the speed reducer is connected to the moving arm 22;

[0077] The inner ring of the bearing is installed on the transmission component, and the outer ring of the bearing is installed on the second connecting arm 24.

[0078] In this embodiment, the speed reducer is a first harmonic speed reducer 231.

[0079] In this embodiment, the bearing is a first crossed roller bearing 233.

[0080] By setting a bearing between the transmission component and the second connecting arm 24 or the first torque sensor 236, the bearing bears the radial force generated by the self-weight of each connecting arm, thereby reducing the interference of this radial force on the measurement result of the first torque sensor 236 and making the torque measurement of the first torque sensor 236 more accurate.

[0081] In this embodiment, as Figure 8 shown, the first rotating joint 23 further includes a deformable member, the deformable member is connected between the first torque sensor 236 and the second connecting arm 24, and the deformable member deforms in the direction towards the bearing.

[0082] By setting a deformable member in the first rotating joint 23, when the first rotating joint 23 is assembled, the cumulative error spacing generated by screw assembly between various parts can be compensated by the deformation of the deformable member, thereby greatly reducing the axial force borne by the torque sensor after the first rotating joint is assembled.

[0083] Specifically, as Figure 7As shown, in this embodiment, the transmission assembly includes a first transmission member 232 and a second transmission member 235, and the deformable member is a first deformable member 234. The first harmonic reducer 231 is fixedly installed on the moving 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 axis of the output shaft of the first harmonic reducer 231. Moreover, 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. Therefore, 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.

[0084] The inner ring of the first crossed roller bearing 233 is installed on the first transmission member 232, and the second transmission member 235 is installed on the first transmission member 232 to axially limit the inner ring of the first crossed roller bearing 233 on the first transmission member 232. The outer ring of the first crossed roller bearing 233 is installed on the second connecting arm 24.

[0085] As Figure 7 shown, the first transmission member 232 is connected to the output shaft of the first harmonic reducer 231 through a first screw 2313. The inner ring of the first crossed roller bearing 233 is connected to the second transmission member 235 through a second screw 2311, and the outer ring of the first crossed roller bearing 233 is connected to the second connecting arm 24 through a third screw 2312. The second transmission member 235 is connected to the first transmission member 232 through a fourth screw 238, and the second transmission member 235 is connected to the first torque sensor 236 through a fifth screw 237. Among them, in the axial direction of the output shaft of the first harmonic reducer 231, the first deformable member 234 is located between the first torque sensor 236 and the second transmission member 235. It should be understood that the first deformable member 234 is not connected between the first torque sensor 236 and the second transmission member 235, but a through hole 2346 ( Figure 9 shown) is provided on the first deformable member 234. The diameter of this through hole is larger than the diameter at the connection of 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 a sixth screw 239, and the first deformable member 234 is connected to the second connecting arm 24 through a seventh screw 2310.

[0086] The self - weight of each connecting arm will generate a radial force at the first rotating joint 23, and this radial force will interfere with the measurement result of the first torque sensor 236. But as Figure 7As shown, in this embodiment, a first crossed roller bearing 233 is provided between the first transmission member 232 and the second connecting arm 24. The first crossed roller bearing 233 bears 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.

[0087] In this embodiment, as Figure 8 and Figure 9 shown, the first deformable member 234 is annular. The first deformable member 234 includes a first connecting portion 2341, a first deformable portion 2343, and a second connecting portion 2344 that are connected in sequence along the radial direction. First annular grooves 2345 and second annular grooves 2342 are respectively provided on opposite side surfaces of the first deformable member 234 in the axial direction. That is, the first annular groove 2345 is provided on the side surface of the first deformable member 234 facing the second transmission member 235, and the second annular groove 2342 is provided on the side surface 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. The thickness of the first deformable portion 2343 in the axial direction is less than the thicknesses of the first connecting portion 2341 and the second connecting portion 2344.

[0088] The first deformable portion 2343 is formed by the first annular groove 2345 and the second annular groove 2342. When subjected to an axial force, the relatively thin first deformable portion 2343 will deform in the direction towards the first crossed roller bearing 233 to achieve the purpose of compensating for the cumulative error spacing.

[0089] In this embodiment, the first deformable member 234 is located between the second transmission member 235 and the first torque sensor 236, specifically referring to the spatial position of the first deformable member 234, rather than the connection relationship.

[0090] The first deformable member 234 utilizes the original assembly gap for the assembly of the first deformable member 234, and the overall structure is more compact.

[0091] In this embodiment, the side surface of the first deformable member 234 provided with the first annular groove 2345 faces the bearing. The inner diameter of the first annular groove 2345 is less than the inner diameter of the second annular groove 2342, the outer diameter of the first annular groove 2345 is less than the outer diameter of the second annular groove 2342, and the outer diameter of the first annular groove 2345 is greater than the inner diameter of the second annular groove 2342.

[0092] The first connecting portion 2341 is connected to the second connecting arm 24, the second connecting portion 2344 is connected to the outer ring of the first torque sensor 236, and the plane where the first deformable portion 2343 is located has an included angle with the force application direction of the first torque sensor 236.

[0093] The structural design of the first annular groove 2345 and the second annular groove 2342 makes it easier for the first deformation part 2343 to deform towards the bearing.

[0094] In another embodiment, as Figure 10 and Figure 11 shown, the difference between this embodiment and the previous one lies in the different shapes of the transmission component and the deformation component, and the setting methods are different.

[0095] Specifically, in this embodiment, the transmission component includes a first transmission member 232 and a third transmission member 2314, the deformation component is a second deformation member 2315, and the first transmission member 232 is sequentially connected to the second connecting arm 24 through the third transmission member 2314, the first torque sensor 236, and the second deformation member 2315.

[0096] In this embodiment, the second deformation member 2315 includes a third connecting portion 23151, a fourth connecting portion 23152, a second deformation portion 23153, and a fifth connecting portion 23154 that are sequentially connected in 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, and the third connecting portion 23151 is connected to the fourth connecting portion 23152 to cover the first torque sensor 236.

[0097] The design of the second deformation member 2315 covering the first torque sensor 236 makes the second deformation member 2315 have a larger volume, and thus has a larger deformable part, and the external second deformation member 2315 is more convenient for assembly.

[0098] In this embodiment, as Figure 10 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 Figure 11 shown, the thickness of the fifth connecting portion 23154 in the axial direction is greater than the thickness of the third connecting portion 23151 in the axial direction, and the thickness of the third connecting portion 23151 in the axial direction is greater than the thickness of the second deformation portion 23153 in the axial direction;

[0099] The third connecting portion 23151 and the fifth connecting portion 23154 are spaced apart in the axial direction, and the fourth connecting portion 23152 is used to connect the third connecting portion 23151 and the fifth connecting portion 23154 in the axial direction.

[0100] The thicknesses of the third connecting portion 23151 and the fifth connecting portion 23154 ensure their respective connection strengths, and at the same time, they are more convenient for deformation compared to the thinnest second deformation portion 23153.

[0101] In another embodiment, as Figure 12 and Figure 13As shown, the difference between this embodiment and the previous two embodiments lies in that the structure of the first rotating joint 23 is different, and the structures and setting methods of the deformable members are also 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 further includes a bearing limiting member 2304, the bearing is a second crossed roller bearing 2305, the deformable member is a third deformable member 2306, and the torque sensor is a second torque sensor 2307, that is:

[0102] The first rotating joint 23 includes a second harmonic reducer 2301, a fourth transmission member 2302, a fifth transmission member 2303, a bearing limiting member 2304, a second crossed roller bearing 2305, a third deformable member 2306, and a second torque sensor 2307. The second harmonic reducer 2301 is fixedly installed on the moving arm 22. The second harmonic reducer 2301, the fourth transmission member 2302, the fifth transmission member 2303, the third deformable member 2306, and the second torque sensor 2307 are arranged in sequence along the axis of the output shaft of the second harmonic reducer 2301.

[0103] The output shaft of the second harmonic reducer 2301 is sequentially connected through the fourth transmission member 2302, the fifth transmission member 2303, the third deformable member 2306, the second torque sensor 2307, and the second connecting arm 24. Therefore, 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 deformable member 2306, and the second torque sensor 2307 in sequence.

[0104] The inner ring of the second crossed roller bearing 2305 is installed on the fourth transmission member 2302 and the third deformable member 2306. Shoulder portions are respectively provided on the fourth transmission member 2302 and the third deformable member 2306 to limit the inner ring of the second crossed roller bearing 2305. The outer ring of the second crossed roller bearing 2305 is installed on the second torque sensor 2307 and the bearing limiting member 2304. Shoulder portions are respectively provided on the second torque sensor 2307 and the bearing limiting member 2304 to limit the outer ring of the second crossed roller bearing 2305.

[0105] As Figure 13 shown, the third deformable member 2306 is annular. The third deformable member 2306 includes a sixth connecting portion 23061, a third deformable portion 23063, and a seventh connecting portion 23062 that are sequentially connected;

[0106] The sixth connecting portion 23061 is connected to the fifth transmission member 2303, and the seventh connecting portion 23062 is connected to the inner ring of the second torque sensor 2307.

[0107] Compared with the previous two embodiments, in this embodiment, the third deformable member 2306 connected between the fifth transmission member 2303 and the second torque sensor 2307 has a smaller volume, a smaller axial dimension, and a more compact overall structure.

[0108] In this embodiment, as Figure 13 shown, the third deformable portion 23063 includes a first deformable body 23064 and a second deformable body 23065 connected in sequence along the radial direction, and the second deformable body 23065 inclines towards the bearing.

[0109] The two deformable bodies form a deformable portion, and at the same time, one of the deformable bodies is set to incline, so that in a limited axial dimension, the third deformable portion 23063 is more convenient for deformation.

[0110] In this embodiment, as Figure 13 shown, an L-shaped seventh connecting member 23066 is provided 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.

[0111] Setting the L-shaped seventh connecting member 23066 can make the best use of the gap between the fifth transmission member 2303 and the second torque sensor 2307, increase the axial dimension of the third deformable member 2306, increase the inclination angle of the second deformable body 23065, and make it more convenient for deformation.

[0112] In another embodiment, as Figure 3 shown, the parallel arm 29 includes a static platform, a moving platform, and three branch chains connecting the static platform and the moving platform, and the fourth rotating joint 28 is connected to the static platform. The connection line between the center point of the static platform and the center point of the moving platform is perpendicular to and intersects the rotation axis of the fourth rotating joint 28; the static platform and the third connecting arm 27 are spaced a preset distance in the rotation axis direction of the fourth rotating joint 28, and in this embodiment, the preset distance can be 100 mm, 150 mm, or 200 mm.

[0113] The fifth rotating joint 210 is connected to the moving platform in the parallel arm 29, and the rotation axis of the fifth rotating joint 210 is perpendicular to the moving platform. The end effector 30 is connected to the fifth rotating joint 210, and the end effector 30 can rotate relative to the moving platform along the rotation axis of the fifth rotating joint 210.

[0114] The fourth rotating joint 28 is connected to the side of the parallel arm 29, so that when the end effector 30 is adjusted by the same angle, the movement amplitude of the parallel arm 29 in this technical solution is smaller.

[0115] Specifically, by comparing Figure 4 and Figure 5 it can be seen that Figure 5An example in the prior art where the fourth rotating joint 28 is connected to the top surface of the parallel arm 29. Figure 4 and Figure 5 in which, the swing angles of the end effector 30 are the same, but Figure 5 the swing amplitude of the parallel arm 29 in Figure 4 is significantly greater than that of the parallel arm 29 in

[0116] In another embodiment, one of the series-parallel hybrid robotic arms of the robot of the present invention and various specific structural implementation manners of the first rotating joint in the series-parallel hybrid robotic arm are disclosed in the above embodiments. It can be understood that the structures of the other rotating joints of the series-parallel hybrid robotic arm of the robot in this embodiment are the same as those of the first rotating joint; the structures of the other series-parallel hybrid robotic arms of the robot in this embodiment are the same as those of this series-parallel hybrid robotic arm.

[0117] This embodiment also discloses a control method based on the robot in any of the above embodiments. The control method includes the following steps:

[0118] S1. Establish the coordinate systems of each joint in the robotic arm;

[0119] S2. Establish the DH motion parameters between each joint coordinate system and the coordinate system of the previous joint of this joint according to the coordinate systems of each joint in the robotic arm;

[0120] S3. Determine the conversion 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 coordinate system of the previous joint of this joint;

[0121] S4. Establish the DH motion parameters between the joint coordinate system of the first joint and the base coordinate system according to the coordinate systems of each joint in the robotic arm;

[0122] S5. Determine the conversion relationship 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;

[0123] S6. Obtain the conversion relationships 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, and determine the conversion relationship between each joint coordinate system and the base coordinate system;

[0124] S7. Obtain the conversion relationships between each joint coordinate system and the base coordinate system, the position vectors of each component in the robotic arm, and the gravity of each component to determine the gravity balance torque of each joint;

[0125] S8. Obtain the conversion relationships between the respective joint coordinate systems and the base coordinate system, and the positions of the acting points of the pulling forces, and determine the relationships between the pulling forces and the forces / moments generated by the pulling forces at each joint;

[0126] S9. Obtain the relationships between the pulling forces and the moments generated by the pulling forces at each joint, the forces / moments measured at each joint, and the gravity balance moments of each joint, and determine the pulling forces at the dragging points on the robotic arm.

[0127] Specifically, in this embodiment, the structure of a single robotic arm on the laparoscopic surgical robot is as Figure 14 shown. The parallel arms in the robotic arm have been simplified to a conical barrel form in Figure 14 for illustration, Figure 14 which includes: the sixth rotational joint axis R1 in the vertical direction; the prismatic joint P1 in the horizontal direction; the first rotational joint axis R2 in the horizontal direction; the second rotational joint axis R3 in the vertical direction; the third rotational joint axis R4 in the horizontal direction; the fourth rotational joint axis R5 in the horizontal direction; the fifth rotational joint axis R6 in the vertical direction; and the rotation axis R7 inclined to the vertical direction (this rotation axis R7 is for the rotation of the surgical end effector along its axis).

[0128] The respective joint coordinate systems in the robotic arm established in the above step S1 are as Figure 15 and Figure 16 shown. The joint coordinates refer to the coordinate systems where each joint is located. For the positive direction of the Z-axis of each coordinate system, when the kinematic pair is a rotational pair, its positive Z-axis direction conforms to the right-hand rule (the direction of the four fingers is the positive rotation direction of the rotational pair, and the direction of the thumb is the positive direction of the Z-axis); when the kinematic pair is a prismatic pair, its positive Z-axis direction is the direction of the component extension. 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 X-axis direction is obtained by cross-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 X-axis direction 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.

[0129] Specifically, in Figure 15 and Figure 16 , the No. 1 coordinate system is fixedly connected to the No. 1 component, and the origin R1 is located at the intersection of the axis of the ① component (the sixth rotational joint) and the moving direction of the ② component (the prismatic 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 by 90° around the Z2-axis, and the positive direction of the Y1-axis conforms to the right-hand rule. The No. 1 coordinate system is the base coordinate system and also the sixth rotational joint coordinate system.

[0130] The No. 2 coordinate system is fixedly connected to the No. ② component (revolute joint). The origin L2 is located at the intersection of Z2 and Z3. The positive direction of the Z2 axis is the extending direction of the No. ② component. The positive direction of the X2 axis is the cross product direction of Z2 and Z3. The positive direction of the Y2 axis conforms to the right-hand rule. The No. 2 coordinate system is the revolute joint coordinate system.

[0131] The No. 3 coordinate system is fixedly connected to the No. ③ component (the first revolute joint). The origin is located at R3. The positive direction of the Z3 axis is perpendicular to the paper plane and outward. The positive direction of the X3 axis is the cross product direction of Z3 and Z4. The positive direction of the Y3 axis conforms to the right-hand rule. The No. 3 coordinate system is the first revolute joint coordinate system.

[0132] The No. 4 coordinate system is fixedly connected to the No. ④ component (the second revolute joint). The origin R4 is located at the intersection of the axis of the No. ④ component and the axis of the No. ⑤ component. 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. The positive direction of the Y4 axis conforms to the right-hand rule. The No. 4 coordinate system is the second revolute joint coordinate system.

[0133] The No. 5 coordinate system is fixedly connected to the No. ⑤ component (the third revolute joint). The origin R5 is located at the intersection of the common perpendicular of the No. ⑤ component and the No. ⑥ component and the axis of the No. ⑤ component. 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. The No. 5 coordinate system is the third revolute joint coordinate system.

[0134] The No. 6 coordinate system is fixedly connected to the No. ⑥ component (the fourth revolute joint). The origin R6 is located at the intersection of the common perpendicular of the No. ⑥ component and the No. ⑦ component and the axis of the No. ⑥ component. 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. The positive direction of the Y6 axis conforms to the right-hand rule. The No. 6 coordinate system is the fourth revolute joint coordinate system.

[0135] The No. 7 coordinate system is fixedly connected to the No. ⑦ component (the fifth revolute joint). The origin R7 is located at the intersection of the No. ⑦ component and the No. ⑧ component. 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. The positive direction of the Y7 axis conforms to the right-hand rule.

[0136] The No. 8 coordinate system is fixedly connected to the No. ⑧ component (the surgical end effector). The origin R8 coincides with R7. The positive direction of the Z8 axis is parallel to the axis direction of the surgical end effector. The positive direction of the X8 axis coincides with X7. The positive direction of the Y8 axis conforms to the right-hand rule.

[0137] The No. 9 coordinate system is fixedly connected to the No. ⑨ component (the No. ⑨ component is virtual, and the No. ⑨ component 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 direction of Z8. The positive direction of X9 is the same as the positive direction of X8. The positive direction of Y8 conforms to the right-hand rule.

[0138] The DH motion parameters between each joint coordinate system in the robotic arm established in the above step S2 and the previous joint coordinate system of that joint are as follows:

[0139]

[0140] In the above table, 1, 2, 3, 4, 5, 6, 7, 8, 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 8th coordinate system, and the 9th coordinate system in sequence.

[0141] Then in the above step S3, for a single joint coordinate system in the robotic arm, the transformation matrix , between each joint coordinate system and the previous joint coordinate system can be expressed as:

[0142]

[0143] where i = 2, 3, 4, …. The transformation matrix from the coordinate system corresponding to the m-th joint to the coordinate system corresponding to the n-th joint can be expressed by Equation (2):

[0144]

[0145] Using formulas (1-1) and (1-2), the transformation matrix 1 i T of each joint coordinate system relative to the first joint coordinate system can be obtained, that is, the transformation relationship between each joint coordinate system and the base coordinate system is determined.

[0146] The DH motion parameters between the joint coordinate system of the first joint established in the above S4 and the base coordinate system are as follows:

[0147]

[0148] In the above table, 0 and 1 represent the base coordinate system and the sixth joint coordinate system respectively.

[0149] Then in the above step S5, according to the DH motion parameters between the joint coordinate system of the first joint and the base coordinate system, the transformation matrix 0 1 T, that is, to determine of the joint coordinate system of the first joint and the base coordinate system can be determined,

[0150] In step S6 above, the transformation relationships between each joint coordinate system and the first joint coordinate system, and between the joint coordinate system of the first joint and the base coordinate system can be used to determine the transformation relationships between each joint coordinate system and the base coordinate system. Then, the transformation 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 with respect to the base coordinate system are calculated as follows:

[0151] .

[0152] According to the method shown in Figure 17 , a single robotic arm is divided into different components. The first connecting arm 21 and the moving 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.

[0153] Let be the position vectors of the centers 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 the coordinate systems 1, 2, 3, 4, 5, and 6 respectively. The center of mass of each component is expressed relative to its attached coordinate system. For example, the position of the center of mass of the first component 401 relative to its attached coordinate system 1 is expressed as . Therefore, the positions of the centers 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 relative to their respective attached coordinate systems are respectively :

[0154]

[0155] where the coordinates of the center of mass of each component relative to the coordinate system attached to each component and the mass are known quantities.

[0156] Using the method of coordinate transformation, the gravity and the acting point of gravity of the first to sixth components are transferred to the coordinate system j attached to the joint to be solved. By calculating the cross product of the position vector of the center of mass of each component and the gravity vector, the joint torque of the acting gravity can be solved.

[0157] Considering the motion characteristics of the moving arm in the second component 402, it can only slide in the Z2-axis direction, so no moment will be generated in the direction of gravity. Based on this analysis, we regard the second component 402 as a rigid body and ignore the influence of its gravitational moment in the calculation. In the subsequent calculation, the parallel arm and the surgical end effector are regarded as a rigid body for calculation.

[0158] The above step S7 specifically includes steps S71 to S74:

[0159] According to the conversion relationship between each joint coordinate system and the base coordinate system, the position vectors of each component in the robotic arm, and the gravity of each component, the principle of gravitational balance moment for each joint is:

[0160] Let the coordinates of the centroid vector of each component in its attached coordinate system be :

[0161] .

[0162] Let the position vectors of each centroid be expressed in the base coordinate system as:

[0163] .

[0164] The solution for the gravitational balance moment of joint j can be obtained: And .

[0165] The representation of the centroid positions of each component in coordinate system j:

[0166] ;

[0167] The expression of the gravity of each component in the No. 1 coordinate system:

[0168] ;

[0169] Among them, E is the identity matrix. The identity matrix is to satisfy the operation method of homogeneous coordinates and actually has no influence on the operation result.

[0170] The gravitational balance moment obtained is:

[0171] .

[0172] Step S71: Determine the gravitational balance moment 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.

[0173] Specifically, the solution for the gravitational balance moment of the sixth revolute joint: .

[0174] The representation of the centroid positions of each component in the No. 1 coordinate system:

[0175] 。

[0176] The expression of the gravity of each component in the No. 1 coordinate system:

[0177] 。

[0178] Gravity balance moment:

[0179] 。

[0180] Step S72: Determine the gravity balance moment of the first rotating joint according to the conversion relationship between the first rotating joint coordinate system and the base coordinate system, the position vector of the third component 403, and the gravity of the third component 403.

[0181] Specifically, the solution of the gravity balance moment of the first rotating joint: 。

[0182] The representation of the centroid positions of each component in the No. 3 coordinate system:

[0183] 。

[0184] The expression of the gravity of each component in the No. 3 coordinate system:

[0185] 。

[0186] Gravity balance moment:

[0187] 。

[0188] Step S73: Determine the gravity balance moment of the second rotating joint according to the conversion relationship between the second rotating joint coordinate system and the base coordinate system, the position vector of the fourth component 404, and the gravity of the fourth component 404.

[0189] Specifically, the solution of the gravity balance moment of the second rotating joint: 。

[0190] The representation of the centroid positions of each component in the No. 4 coordinate system:

[0191] 。

[0192] The expression of the gravity of each component in the No. 4 coordinate system:

[0193] 。

[0194] Gravity balance moment:

[0195] 。

[0196] Step S74. Determine the gravity balance moment of the third rotating joint according to the conversion relationship between the third rotating joint coordinate system and the base coordinate system, the position vector of the 5th component 405, and the gravity of the 5th component 405.

[0197] Specifically, solve for the gravity balance moment of the third rotating joint: 。

[0198] Representation of the centroid positions of each component in the 5th coordinate system:

[0199] 。

[0200] Representation of the gravity of each component in the 5th coordinate system:

[0201] 。

[0202] Gravity balance moment:

[0203] 。

[0204] Step S75. Determine the gravity balance moment of the fourth rotating joint according to the conversion relationship between the fourth rotating joint coordinate system and the base coordinate system, the position vector of the 6th component 406, and the gravity of the 6th component 406.

[0205] Specifically, solve for the gravity balance moment of the fourth rotating joint: 。

[0206] Representation of the centroid positions of each component in the 6th coordinate system:

[0207] 。

[0208] Representation of the gravity of each component in the 6th coordinate system:

[0209] 。

[0210] Gravity balance moment:

[0211] 。

[0212] The above step S7 calculates the gravity balance moments of each joint. Before the surgery, the doctor or the doctor's assistant also needs to drag the robotic arm to position it, so that the robotic arm is dragged to the required position before the surgery. Therefore, it is also necessary to calculate the magnitude of the dragging force applied to the robotic arm. The above step S8 specifically includes steps S81 to S86:

[0213] The principle of solving the drag force / moment on joint j is as follows: Assume that the position of the acting point of the drag force at the dragging point on the sixth component 406 is known, and the description of the acting point in the sixth coordinate system is :

[0214] .

[0215] is a known quantity. Let the drag force at the dragging point be F, and the description of F in the sixth coordinate system is :

[0216] .

[0217] Then the description of the acting point of the drag force in the base coordinate system is:

[0218] .

[0219] Then the description of the drag force in the base coordinate system is:

[0220] .

[0221] The drag torque on joint j can be solved therefrom, and the solving steps are as follows:

[0222] Then the description of the acting point of the drag force in coordinate system j is:

[0223] .

[0224] Then the description of the drag force in coordinate system j is:

[0225] .

[0226] The torque generated by the drag force at joint j is:

[0227] .

[0228] Step S81: Determine the relationship between the drag force and the torque generated by the drag force at the sixth rotational joint according to the conversion relationship between the sixth rotational joint coordinate system and the base coordinate system and the position of the acting point of the drag force.

[0229] Specifically, the solution of the drag torque of the sixth rotational joint:

[0230] Then the description of the acting point of the drag force in the first coordinate system is:

[0231] .

[0232] Then the description of the drag force in the first coordinate system is:

[0233] .

[0234] The torque generated by the towing force at the sixth rotating joint is:

[0235] 。

[0236] Step S81 is to represent the torque generated by the towing force at the sixth rotating joint through the towing force F0, which facilitates the subsequent use of the elimination method in Equation (1-4) to solve for the towing force F0.

[0237] Step S82: Determine the relationship between the towing force and the force generated by the towing 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 acting point of the towing force.

[0238] Specifically, for the solution of the towing force of the moving joint:

[0239] Then the description of the acting point of the towing force in the No. 2 coordinate system is:

[0240] 。

[0241] Then the description of the towing force in the No. 2 coordinate system is:

[0242] 。

[0243] The force generated by the towing force at joint 2 is:

[0244] 。

[0245] Step S82 is to represent the force generated at the moving joint through the towing force F0, which facilitates the subsequent use of the elimination method in Equation (1-4) to solve for the towing force F0.

[0246] Step S83: Determine the relationship between the towing force and the torque generated by the towing force at the first rotating joint according to the conversion relationship between the first rotating joint coordinate system and the base coordinate system and the position of the acting point of the towing force.

[0247] Specifically, for the solution of the towing torque of the first rotating joint:

[0248] Then the description of the acting point of the towing force in the No. 3 coordinate system is:

[0249] 。

[0250] Then the description of the towing force in the No. 3 coordinate system is:

[0251] 。

[0252] The torque generated by the towing force at joint 3 is:

[0253] 。

[0254] Step S83 is to represent the torque generated by the towing force at the first rotating joint through the towing force F0, which facilitates the subsequent use of the elimination method in Equation (1-4) to solve for the towing force F0.

[0255] Step S84: Determine the relationship between the towing force and the torque generated by the towing force at the second rotating joint according to the conversion relationship between the second rotating joint coordinate system and the base coordinate system and the position of the acting point of the towing force.

[0256] Specifically, the solution of the towing torque of the second rotating joint is as follows:

[0257] Then the description of the acting point of the towing force in the No. 4 coordinate system is:

[0258] 。

[0259] Then the description of the towing force in the No. 4 coordinate system is:

[0260] 。

[0261] The torque generated by the towing force at joint 4 is:

[0262] 。

[0263] Step S84 is to represent the torque generated by the towing force at the second rotating joint through the towing force F0, which facilitates the subsequent use of the elimination method in Equation (1-4) to solve for the towing force F0.

[0264] Step S85: Determine the relationship between the towing force and the torque generated by the towing force at the third rotating joint according to the conversion relationship between the third rotating joint coordinate system and the base coordinate system and the position of the acting point of the towing force.

[0265] Specifically, the solution of the towing torque of the third rotating joint is as follows:

[0266] Then the description of the acting point of the towing force in the No. 5 coordinate system is:

[0267] 。

[0268] Then the description of the towing force in the No. 5 coordinate system is:

[0269] 。

[0270] The torque generated by the towing force at joint 5 is:

[0271] 。

[0272] Step S85 is to represent the moment generated by the towing force at the third rotating joint through the towing force F0, which facilitates the subsequent use of the elimination method in equation (1-4) to solve for the towing force F0.

[0273] Step S86: Determine the relationship between the towing force and the moment generated by the towing force at the fourth rotating joint based on the conversion relationship between the coordinate system of the fourth rotating joint and the base coordinate system and the position of the acting point of the towing force.

[0274] Specifically, the solution of the towing moment at the fourth rotating joint:

[0275] Then the description of the acting point of the towing force in the No. 6 coordinate system is:

[0276] 。

[0277] Then the description of the towing force in the No. 6 coordinate system is:

[0278] 。

[0279] The moment generated by the towing force at joint 6 is:

[0280] 。

[0281] Step S86 is to represent the moment generated by the towing force at the fourth rotating joint through the towing force F0, which facilitates the subsequent use of the elimination method in equation (1-4) to solve for the towing force F0.

[0282] The specific principle of the above step S9 is: Force sensors / torque sensors are installed on each joint. Then, according to the force / torque values obtained by the force sensors / torque sensors installed at each joint, the moments measured on the sixth rotating joint, the forces measured on the moving joint, the moments measured on the first rotating joint, the moments measured on the second rotating joint, the moments measured on the third rotating joint, and the moments measured on the fourth rotating joint are successively 。According to:

[0283] The moment measured by the force / torque sensor = the gravity balance moment on each joint + the towing moment generated by the towing force at each joint;

[0284] Then the following equations can be established:

[0285]

[0286] Among them, F p1 is the force measured by the force sensor on the moving joint. Select any three equations from the above equation set and use the elimination method to solve, and the towing force at the towing point can be obtained 。

[0287] The basic principles, main features and advantages of the present invention have been shown and described above. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and all these changes and improvements fall within the scope of the present invention claimed.

Claims

1. A laparoscopic surgical robot, characterized in that, It includes a series arm, a parallel arm, a fifth rotating joint and a surgical end effector connected in sequence. The series 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 rotating joint is perpendicular to the vertical direction. The rotation axis of the second rotating joint is perpendicular to the rotation axis of the first rotating joint, and the rotation axis of the third rotating joint is perpendicular to the rotation axis of the second rotating joint; The parallel arm includes a static platform and a moving platform. The fourth rotating joint is connected to the static platform, and the connection line between the center point of the static platform and the center point of the moving platform is perpendicular to and intersects the rotation axis of the fourth rotating joint. 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 rotating joint; The surgical end effector is arranged offset from the first rotating joint in the vertical direction.

2. The robot according to claim 1, characterized in that, The first rotating joint includes a reducer, a bearing, a transmission component 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 installed on the transmission component, and the outer ring of the bearing is installed on the second connecting arm or the torque sensor.

3. The robot according to claim 2, wherein The first rotating joint further includes a deformable member. The deformable member is connected between the transmission component and the torque sensor or between the torque sensor and the second connecting arm, and the deformable member deforms in the direction towards the bearing.

4. The robot according to claim 3, wherein, The deformable member is annular. The deformable member includes a first connecting portion, a first deformable portion and a second connecting portion connected in sequence in the radial direction. The first annular groove and the second annular groove are respectively provided on the opposite side surfaces of the deformable member in the axial direction. The first deformable portion is formed between the first annular groove and the second annular groove, and the thickness of the first deformable portion in the axial direction is less than the thickness of the first connecting portion and the second connecting portion.

5. The robot according to claim 4, characterized in that, The deformable member is located between the transmission component and the torque sensor.

6. The robot according to claim 5, characterized in that The side surface of the deformable member provided with the first annular groove faces the bearing. The inner diameter of the first annular groove is less than the inner diameter of the second annular groove, the outer diameter of the first annular groove is less than the outer diameter of the second annular groove, and the outer diameter of the first annular groove is greater than the inner diameter of the second annular groove; The first connecting portion is connected to the second connecting arm, the second connecting portion is connected to the outer ring of the torque sensor, and the plane where the first deformable portion is located has an angle with the force receiving direction of the torque sensor.

7. The robot according to claim 5, characterized in that, The side surface of the deformable member provided with the first annular groove faces the bearing. The inner diameter of the first annular groove is less than the inner diameter of the second annular groove, the outer diameter of the first annular groove is less than the outer diameter of the second annular groove, and the outer diameter of the first annular groove is greater than the inner diameter of the second annular groove; The first connecting portion is connected to the second connecting arm, the second connecting portion is connected to the outer ring of the torque sensor, and the plane where the first deformable portion is located has an angle with the force receiving direction of the torque sensor.

8. The robot according to claim 7, characterized in that, 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 connecting portion and the fifth connecting portion are spaced apart in the axial direction, and the fourth connecting portion is used to connect the third connecting portion and the fifth connecting portion in the axial direction.

9. The robot according to claim 3, characterized in that, The deformable member is annular, and the deformable member includes a sixth connecting portion, a third deformation portion, and a seventh connecting portion that are sequentially connected; The sixth connecting portion is connected to the transmission assembly, and the seventh connecting portion is connected to the inner ring of the torque sensor.

10. The robot according to claim 9, characterized in that, The third deformation portion includes a first deformable body and a second deformable body that are sequentially connected in the radial direction, and the second deformable body is inclined toward the bearing.

11. The robot according to claim 10, characterized in that, An L-shaped seventh connecting member is provided on the seventh connecting portion, and the short side of the L shape on the seventh connecting member is connected to the seventh connecting portion.

12. A control method for a robot based on any one of claims 1-11, characterized in that, Comprising the following steps: Obtain 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, and determine the conversion relationship between each joint coordinate system and the base coordinate system; Obtain the conversion relationship between each joint coordinate system and the base coordinate system, the position vectors of the components in the robotic arm, and the gravity of each component to determine the gravity balance torque of each joint; Obtain the conversion relationship between each joint coordinate system and the base coordinate system, and the position of the action point of the pulling force, and determine the relationship between the pulling force and the force / moment generated by the pulling force at each joint; Obtain the relationship between the pulling force and the torque generated by the pulling force at each joint, the measured force / moment at each joint, and the gravity balance torque of each joint, and determine the pulling force at the pulling point on the robotic arm.

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