Novel telecentric mechanism microscopic anastomosis surgical robot slave manipulator device

Abstract

The invention provides a novel telecentric mechanism microscopic anastomosis surgical robot slave manipulator device, and relates to the field of medical instruments, the novel telecentric mechanism microscopic anastomosis surgical robot slave manipulator device comprises a novel telecentric mechanism, a position adjusting mechanism and a testing module, the position adjusting mechanism is composed of three completely consistent linear motion modules and is used for adjusting the coordinate position of the novel telecentric mechanism, and the testing module is used for testing the position of the novel telecentric mechanism. The novel telecentric mechanism comprises an AB deflection motion base, a BC rod, an AF rod, a CE rod, an EH rod, an FJ rod, an HI rod, an IJ autorotation motion base and a pitching driving motor. The position-posture decoupling configuration is adopted, the high-precision position requirement is met through the three-axis platform, the large rotation range requirement is met through the novel telecentric mechanism, the small position-large posture-high precision motion requirement of the microscopic anastomosis operation is met, the motion flexibility of the robot is improved, meanwhile, the decoupling configuration can reduce the complexity of a control algorithm, and the control precision of the robot is improved. And the movement precision and the safety in the operation process are improved.

Description

Technical Field

[0001] The invention relates to the technical field of medical devices, in particular to a novel telecentric mechanism micro-anastomosis surgical robot slave device. Background Art

[0002] Microanastomosis is an important surgical technique in microsurgery. It requires doctors to use medical microscopes (5-40X) to repair and reconstruct tiny blood vessels (0.3-3mm in diameter). It is widely used in some delicate reconstruction surgeries that require long-distance transplantation, such as breast reconstruction, finger replantation, and facial transplantation. General microanastomosis requires the cooperation of multiple types of surgical instruments. The operation steps can be briefly described as follows: the doctor first fixes the blood vessel with micro forceps and vascular clamps, and uses a background board to provide a clear surgical field; further, the doctor needs to use micro scissors to peel off the outer membrane of the blood vessel as much as possible, which provides the necessary basis for preventing postoperative thrombosis; after further dilation of the blood vessel with the help of a vascular dilator, the doctor can use a needle holder and micro forceps for anastomosis. The needle insertion process is the most important step in the anastomosis operation, which will directly affect the anastomosis quality. A skilled doctor can suture up to 10 stitches on a blood vessel with a diameter of 1mm.

[0003] Although artificial vascular anastomosis is still regarded as the gold standard for microsurgery, there are still some objective factors that make this operation difficult to perform. The first is the flexibility of the movement mechanism. When performing the needle insertion action, the human hand needs to perform high-precision position movement, but when tying the knot, it needs to change its posture flexibly. This "small position-large posture-high precision" movement mode brings certain challenges to manual operation. Secondly, there is the physiological tremor of the human hand. Although this can be suppressed to about 70um through practice, there are still certain limitations for the 30um precision requirement for micro-anastomosis operations. Finally, due to the limitation of the working space, all operations need to be performed in a narrow surgical field to ensure safety, and at the same time, it should be ensured that there is no direct interference with the microscope and the patient.

[0004] Existing solutions and shortcomings: Robot-assisted surgery has been verified in laparoscopic surgery, neurosurgery, ophthalmology and other fields with its excellent tremor suppression ability and flexible motion scaling performance. However, the relevant technology is not fully applicable in the field of micro-anastomosis. For example, the Davinci laparoscopic surgical robot has successfully achieved 1.5mm arterial vascular ex vivo anastomosis, but due to the limitation of motion scaling and insufficient resolution, it cannot be applied to vascular anastomosis with a diameter of less than 1mm. At the same time, due to its large size, it is not conducive to use in combination with medical microscopes. The NeuroArm neurosurgical robot also has insufficient positioning accuracy (1mm) and cannot cope with the problem of micro-anastomosis surgery. In addition, there is also the problem of incompatibility of surgical instruments. The PRECEYES ophthalmic surgical robot uses a double parallelogram mechanism to achieve telecentric motion, achieves high motion accuracy, and completes the world's first robot-assisted retinal macular detachment surgery, but due to the lack of freedom of the robot, it cannot be directly applied to the field of micro-anastomosis. At present, some micro-anastomosis-specific surgical robots can break through the accuracy limit of 1mm, but there are still some problems that are difficult to solve. MUSA's robotic arm uses a simple serial configuration to achieve anastomosis, and its posture movement mode does not match the surgical characteristics. It has poor dexterity and the problem of multi-joint motion error accumulation is difficult to eliminate, which limits the accuracy. Symani robot uses wire drive to obtain a smaller terminal volume and flexible wrist joint movement, but the creep effect of the wire rope is still difficult to solve, which poses a more severe challenge to precise control and system stability. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the deficiencies of the prior art, the present invention provides a novel telecentric mechanism micro-anastomosis surgical robot slave device, which solves the problems raised in the above-mentioned background technology.

[0007] (II) Technical solution

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions: a novel telecentric mechanism micro-anastomosis surgical robot slave device, including a novel telecentric mechanism, a position adjustment mechanism, and a test module. The position adjustment mechanism is composed of three completely identical linear motion modules and is used to adjust the coordinate position of the novel telecentric mechanism. The novel telecentric mechanism includes an AB deflection motion base, a BC rod, an AF rod, a CE rod, an EH rod, an FJ rod, a HI rod, an IJ rotation motion base, and a pitch drive motor. The AB deflection motion base, AF rod and FJ rod are hinged in sequence, the BC rod, CE rod, EH rod and HI rod are hinged in sequence, the bottom end of the BC rod is hinged to the middle end of the AB deflection motion base, the middle ends of the CE rod and AF rod are hinged, the middle ends of the EH rod and FJ rod are hinged, the head and tail ends of the IJ rotation motion base are hinged to the top ends of the FJ rod and HI rod, the pitch drive motor is used to drive the hinge shaft between the AF rod and the FJ rod, and the test module is arranged on the IJ rotation motion base.

[0009] Preferably, the test module includes a test rod, a spherical measuring head, and a self-rotation drive motor, wherein the self-rotation drive motor is arranged on an IJ self-rotation motion base, the test rod is fixedly connected to the drive shaft of the self-rotation drive motor, and the spherical measuring head is threadedly connected to the test rod.

[0010] Preferably, the spherical measuring head is a three-coordinate special measuring head with a ball head diameter of mm, which can accurately measure the motion performance of the designed robot's slave hand.

[0011] Preferably, the linear motion module includes a support frame, a stepper motor, a lead screw, a nut, a guide rail, and a slider. Both ends of the lead screw are pivotally connected to the support frame through bearing seats. The stepper motor is connected to the lead screw. The nut thread is adapted outside the lead screw. The guide rail is arranged at the bottom of the support frame along the length direction of the lead screw. The slider is slidably adapted on the guide rail and is connected to the nut. The support frame of the upper linear motion module is connected to the nut of the lower linear motion module.

[0012] Preferably, it also includes an angle connecting plate, a rotating table, and a rotating motor. The angle connecting plate is connected to the nut of the uppermost linear motion module through a connecting block. The tail end of the AB deflection motion base is rotatably set on the angle connecting plate through the rotating table. The rotating motor is set on the rotating table and is used to drive the rotating table to rotate.

[0013] Preferably, the motion scaling ratio relationship among the AB segment, CE segment, and DF segment on the AB deflection motion base, the BC rod, the AF rod, and the CE rod is as shown in the following formula:

[0014] (III) Beneficial effects

[0015] The present invention provides a novel telecentric mechanism micro-anastomosis surgery robot slave device, which has the following beneficial effects:

[0016] 1. The new telecentric mechanism micro-anastomosis surgery robot slave device adopts a position-posture decoupling configuration. The three-axis platform meets the high-precision position requirements, and the new telecentric mechanism meets the larger rotation range requirements. It meets the "small position-large posture-high precision" motion requirements of micro-anastomosis surgery and improves the robot's motion flexibility. At the same time, the decoupling configuration can reduce the complexity of the control algorithm, improve the motion accuracy and the safety of the surgical process.

[0017] 2. The new telecentric mechanism of the micro-anastomosis surgical robot slave device is designed based on the new double triangle principle, which ensures that the surgical instrument can perform flexible posture adjustment movements in a narrow working space. Compared with the traditional double parallelogram telecentric mechanism, it has a more compact size and a larger motion scaling ratio.

[0018] 3. The new telecentric mechanism micro-anastomosis surgery robot slave device has a symmetrical arrangement of the connecting rod group of the telecentric mechanism, which improves the structural rigidity of the slave hand and reduces the influence of the flexural deformation of the telecentric mechanism caused by gravity during the deflection process, thereby ensuring the movement accuracy of the robot slave hand during posture changes. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is the overall axonometric diagram of the present invention;

[0020] Figure 2 It is a schematic diagram of the position adjustment mechanism of the present invention;

[0021] Figure 3 It is a side sectional view of the novel telecentric mechanism of the present invention;

[0022] Figure 4 A process diagram for constructing the novel telecentric mechanism of the present invention;

[0023] Figure 5 This is a diagram showing the input-output motion ratio relationship of the first embodiment of the present invention;

[0024] Figure 6 This is a diagram showing the input-output motion ratio relationship of the second embodiment of the present invention;

[0025] Figure 7 This is a diagram showing the input-output motion ratio relationship of embodiment 3 of the present invention.

[0026] In the figure: 1 new telecentric mechanism, 2 position adjustment mechanism, 3 test module, 11AB deflection motion base, 12BC rod, 13AF rod, 14CE rod, 15EH rod, 16FJ rod, 17HI rod, 18IJ rotation motion base, 19 pitch drive motor, 21 support frame, 22 stepper motor, 23 lead screw, 24 nut, 25 guide rail, 26 slider, 31 spherical measuring head, 32 measuring rod, 33 rotation drive motor, 4 connecting block, 5 angle connecting plate, 6 rotating table, 7 rotating motor. DETAILED DESCRIPTION

[0027] The embodiment of the present invention provides a novel telecentric mechanism micro-anastomosis surgery robot slave device, such as Figure 1-7 As shown, it includes a novel telecentric mechanism 1, a position adjustment mechanism 2, and a test module 3.

[0028] like Figure 2 As shown, the position adjustment mechanism 2 is composed of three completely identical linear motion modules, and is used to adjust the coordinate position of the novel telecentric mechanism 1, and realize the adjustment in the three directions of X, Y, and Z respectively. The linear motion module includes a support frame 21, a stepper motor 22, a lead screw 23, a nut 24, a guide rail 25, and a slider 26. The two ends of the lead screw 23 are pivotally connected to the support frame 21 through a bearing seat, the stepper motor 22 is fixedly connected to the support frame 21 through bolts, the drive shaft of the stepper motor 22 is connected to the lead screw 23, the nut 24 is threadedly adapted outside the lead screw 23, the lead screw 23 and the nut 24 together form a spiral motion pair, the guide rail 25 is arranged at the bottom of the support frame 21 along the length direction of the lead screw 23, the slider 26 is slidably adapted on the guide rail 25, the slider 26 and the guide rail 25 form a linear motion pair, the slider 26 is connected to the nut 24, and the support frame 21 located at the upper linear motion module is connected to the nut 24 of the lower linear motion module. The linear motion module converts the rotational motion of the stepper motor 22 into the linear motion of the nut 24 .

[0029] The device also includes an angle connecting plate 5, a rotating platform 6, and a rotating motor 7. The angle connecting plate 5 is connected to the nut 24 of the uppermost linear motion module through a connecting block 4. The tail end of the AB deflection motion base 11 is rotatably arranged on the angle connecting plate 5 through the rotating platform 6. The rotating motor 7 is arranged on the rotating platform 6 and is used to drive the rotating platform 6 to rotate. The driving shaft of the rotating motor 7 is connected to the rotating platform 6 through a worm gear kinematic pair. It is used to adjust the angle of the novel telecentric mechanism 1.

[0030] like Figure 2As shown, the test module 3 includes a test rod 32, a spherical measuring head 31, and a self-rotation drive motor 33. The self-rotation drive motor 33 is arranged on the IJ self-rotation motion base 18. The test rod 32 is fixedly connected to the drive shaft of the self-rotation drive motor 33. The test rod 32 is fixedly connected to the self-rotation drive motor 33 by positioning the shaft hole and tightening the set bolts. The spherical measuring head 31 is threadedly connected to the test rod 32. The spherical measuring head 31 is a three-coordinate special measuring head with a ball head diameter of 1 mm, which can accurately measure the motion performance of the designed robot slave hand.

[0031] like Figure 1 and Figure 3 As shown, the novel telecentric mechanism 1 includes an AB deflection motion base 11, a BC rod 12, an AF rod 13, a CE rod 14, an EH rod 15, an FJ rod 16, a HI rod 17, an IJ rotation motion base 18, and a pitch drive motor 19. The AB deflection motion base 11, the AF rod 13, and the FJ rod 16 are hinged in sequence, the BC rod 12, the CE rod 14, the EH rod 15, and the HI rod 17 are hinged in sequence, the bottom end of the BC rod 12 is hinged to the middle end of the AB deflection motion base 11, the middle ends of the CE rod 14 and the AF rod 13 are hinged, the middle ends of the EH rod 15 and the FJ rod 16 are hinged, the head and tail ends of the IJ rotation motion base 18 are hinged to the top ends of the FJ rod 16 and the HI rod 17, the pitch drive motor 19 is fixed on the AF rod 13, and is used to drive the hinge shaft between the AF rod 13 and the FJ rod 16, and the test module 3 is arranged on the IJ rotation motion base 18.

[0032] Specifically, the novel telecentric mechanism 1 is designed based on the double triangle principle, and the connecting rod assembly composed of the AB deflection motion base 11, BC rod 12, AF rod 13, CE rod 14, EH rod 15, FJ rod 16, HI rod 17, and IJ rotation motion base 18 is arranged symmetrically in space to obtain higher structural stiffness, and the length of each rod is determined according to the double triangle principle.

[0033] like Figure 4 As shown, the design principle of the new telecentric mechanism 1 is: parallel and unequal length connecting rods AD and BC can construct a set of similar triangles AOD and BOC in the plane, such as Figure 4 As shown in a, due to the characteristics of similar triangles, the extension line of CD will definitely intersect the extension line of the connecting rod AB at point O, which lays a geometric foundation for creating the telecentric fixed point O. However, at this time, point O is still in a floating position on the connecting rod CD. This is because when the connecting rod AD swings, the length of the rod OD is constantly changing. In order to obtain a stable point O, connecting rods DE, EF, and FC of equal length are symmetrically arranged along the direction of the connecting rod CD, as shown in Figure 4As shown in Fig. b, this construction method geometrically obtains a set of congruent triangles AOD and DOE, which ensures that the connecting rod OE is a fixed value. Furthermore, in order to provide a stable parallel constraint and reduce the number of hinge points, the connecting rod DJ and the connecting rod DI are added inside the connecting rod, as shown in Fig. Figure 4 As shown in Figure 3, the parallelograms ABJD and DIFE provide sufficient angle constraints for the diamond DJCI, thereby maintaining the motion characteristics of the telecentric mechanism. In other words, changing the position of the non-fixed link in the parallelogram can obtain a new variant mechanism. First, the non-fixed link AD is translated along the straight line AB to obtain the first variant mechanism, as shown in Figure 3. Figure 4 Finally, the non-fixed link ED can be translated along the straight line EF to obtain the second variant mechanism, as shown in Figure 4 e. Comparing the variant mechanism with the original mechanism, it is not difficult to find that the variant mechanism provides a more flexible mechanism installation distance OB and instrument installation distance OF, which brings greater flexibility to the use of the telecentric mechanism; at the same time, under the same motion parameters, the second variant mechanism has a more compact size than the original mechanism. The motion diagram of the constructed new telecentric mechanism 1 is shown in Figure 4 As shown in Figure f, for ease of understanding, the correspondence between the connecting rods in Figure f and the model in the technical solution is as follows: AB is the AB deflection motion base 11; BC is the BC rod 12; AF is the AF rod 13; CE is the CE rod 14; EH is the EH rod 15; FJ is the FJ rod 16; HI is the HI rod 17; IJ is the IJ rotation motion base 18.

[0034] by Figure 4 The joint F in f is used as the input joint of the pitch motion motor 19, and the motion scaling ratio relationship between the AB segment, CE segment, and DF segment on the AB yaw motion base 11, the BC rod 12, the AF rod 13, and the CE rod 14 is as shown in the following formula;

[0035] According to the above formula, three embodiments are used to explore the different motion performances of the telecentric mechanism when the lengths of the three rods of segment AB, segment CE, and segment DF have different mathematical relationships.

[0036] Embodiment 1, when L DF >(L CE -L AB ), the input-output motion ratio is as follows: Figure 5 As shown, the ratio at this time is less than 1, and the new telecentric mechanism 1 presents the performance of motion reduction, and the maximum input angle is 180°.

[0037] Embodiment 2, when L DF =(L CE -L AB ), the input-output motion relationship is as follows Figure 6 As shown, at this time, the ratio of input motion / output motion is equal to 1, and the new telecentric mechanism 1 does not have motion scaling performance. In particular, the new telecentric mechanism 1 at this time degenerates into a double parallelogram mechanism.

[0038] Embodiment 3, when L DF <(L CE -L AB ), the input-output motion ratio is as follows: Figure 7 As shown, the ratio at this time is greater than 1, the new telecentric mechanism 1 exhibits the function of motion amplification, and the maximum output angle is 180°.

[0039] By exploring different rod length conditions, we can draw the following conclusions: First, the double parallelogram mechanism is only a special form, and its motion scaling ratio is not adjustable. Second, we can choose motion reduction or motion amplification by changing the relationship between DF and (DF-AB). Third, the numerical adjustment of the above motion scaling can be further determined by DF / (DF-AB).

[0040] Kinematic model of the robot: The new telecentric mechanism 1 micro-anastomosis surgery robot adopts a posture decoupling configuration from the hand device, and its kinematics can be expressed as follows:

[0041] T=T p (q1,q2,q3)T o (q4,q5,q6)#(1)

[0042] Where T p is the position transformation matrix, (x, y, z) represents the motion parameters of the linear table, which can be expressed as follows:

[0043] T p =Trans(x,q1)Trans(y,q2)Trans(z,q3)#(2)

[0044] Where Trans(i,j) represents the transformation matrix of moving distance j along the i axis, q i is the output angle of the driving motor. For the other part of the direction transformation matrix T o , which contains the angle information of the RCM operator's rotation axis, as shown in the following formula:

[0045] T o =Rot(y,Φ0)Rot(x,Ψ)Rot(y,Φ)Rot(z,Θ)#(3)

[0046] Where Rot(i,j) represents the transformation matrix of the rotation angle j around the i-axis, Φ0 represents the initial pitch angle of the RCM manipulator, (Ψ,Φ,Θ) are independently driven by the (q4,q5,q6) motors respectively, and their corresponding relationship is expressed as follows:

[0047]

[0048] Substituting equations (2)-(4) into equation (1) yields the complete robot kinematic model. Obviously, this posture decoupling configuration greatly simplifies the kinematic model, which is also helpful for error modeling and control model construction.

[0049] Working principle of the robot slave: The new telecentric mechanism micro-anastomosis surgery robot slave device adopts a master-slave operation mode, including a remote operation table, a surgical operation table and a control module. The surgical operation table consists of a surgical microscope and a micro-anastomosis surgery robot slave. The robot slave completes surgical interactive actions in the surgical area. The process is captured in real time by the surgical microscope, and the video signal is transmitted to the remote operation table. The remote operation table includes a display, a master operator and a PC host. The doctor observes the display and uses the master operator to complete the remote surgery. The motion instructions of the master operator are sent to the control module via the PC host. The control module consists of a controller and a driver. The controller further processes the received motion instructions and converts them into electrical signals through the driver and sends them to the micro-anastomosis robot slave to achieve corresponding motor control.

[0050] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A novel telecentric mechanism micro-anastomosis surgery robot slave device, comprising a novel telecentric mechanism (1), a position adjustment mechanism (2), and a test module (3), wherein the position adjustment mechanism (2) is composed of three completely identical linear motion modules and is used to adjust the coordinate position of the novel telecentric mechanism (1), and is characterized in that: The novel telecentric mechanism (1) comprises an AB deflection motion base (11), a BC rod (12), an AF rod (13), a CE rod (14), an EH rod (15), an FJ rod (16), an HI rod (17), an IJ rotation motion base (18), and a pitch drive motor (19); the AB deflection motion base (11), the AF rod (13), and the FJ rod (16) are hinged in sequence; the BC rod (12), the CE rod (14), the EH rod (15), and the HI rod (17) are hinged in sequence; and the BC rod ( The bottom end of the AB deflection motion base (12) is hinged to the middle end of the AB deflection motion base (11), the middle ends of the CE rod (14) and the AF rod (13) are hinged, the middle ends of the EH rod (15) and the FJ rod (16) are hinged, the head and tail ends of the IJ rotation motion base (18) are hinged to the top ends of the FJ rod (16) and the HI rod (17), the pitch drive motor (19) is used to drive the hinge shaft between the AF rod (13) and the FJ rod (16), and the test module (3) is arranged on the IJ rotation motion base (18).

2. According to claim 1, the novel telecentric mechanism micro-anastomosis surgery robot slave device is characterized by: The test module (3) comprises a test rod (32), a spherical measuring head (31), and a self-rotation drive motor (33); the self-rotation drive motor (33) is arranged on an IJ self-rotation motion base (18); the test rod (32) is fixedly connected to a drive shaft of the self-rotation drive motor (33); and the spherical measuring head (31) is threadedly connected to the test rod (32).

3. According to claim 2, the novel telecentric mechanism micro-anastomosis surgery robot slave device is characterized by: The spherical measuring head (31) is a three-coordinate special measuring head with a spherical head diameter of 1 mm, and can accurately measure the motion performance of the designed robot slave hand.

4. According to claim 1, the novel telecentric mechanism micro-anastomosis surgery robot slave device is characterized by: The linear motion module comprises a support frame (21), a stepper motor (22), a lead screw (23), a nut (24), a guide rail (25), and a slider (26); both ends of the lead screw (23) are pivotally connected to the support frame (21) through a bearing seat; the stepper motor (22) is connected to the lead screw (23); the nut (24) is threadedly fitted outside the lead screw (23); the guide rail (25) is arranged at the bottom of the support frame (21) along the length direction of the lead screw (23); the slider (26) is slidably fitted on the guide rail (25) and is connected to the nut (24); the support frame (21) located at the upper linear motion module is connected to the nut (24) of the lower linear motion module.

5. The novel telecentric mechanism micro-anastomosis surgery robot slave device according to claim 4 is characterized by: It also includes an angle connecting plate (5), a rotating platform (6), and a rotating motor (7); the angle connecting plate (5) is connected to a nut (24) of the uppermost linear motion module via a connecting block (4); the tail end of the AB deflection motion base (11) is rotatably arranged on the angle connecting plate (5) via the rotating platform (6); the rotating motor (7) is arranged on the rotating platform (6) and is used to drive the rotating platform (6) to rotate.

6. The novel telecentric mechanism micro-anastomosis surgery robot slave device according to claim 1 is characterized by: The motion scaling ratio relationship among the AB segment, the CE segment and the DF segment on the AB deflection motion base (11), the BC rod (12), the AF rod (13) and the CE rod (14) is as shown in the following formula:

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