Master-slave flexible continuum robot for surgical operation and its control method

Abstract

The invention relates to a master-slave flexible continuum robot for surgical operations and a control method thereof, which belongs to the field of bionic robots. The invention comprises a robot slave hand and a robot master hand, wherein the robot slave hand comprises a first slave hand component, a second slave hand component and a third slave hand component connected end to end, wherein the first slave hand component, the second slave hand component and the third slave hand component are driven by a wire, and are connected at the ends of the corresponding components by four ropes, and the degree of freedom of the first slave hand component, the second slave hand component and the third slave hand component are driven by changing the length of the rope; the robot master hand comprises three straight rods of the same structure and variable length connected in sequence, and a posture sensor is installed in each straight rod. The robot and the control method of the invention have the advantages of high precision, flexible and reliable operation, fast response speed and high real-time performance.

Description

Technical Field

[0001] The invention relates to a master-slave type flexible continuum robot, in particular to a master-slave type flexible continuum robot for surgical operations and a control method thereof, and belongs to the field of bionic robots. Background Art

[0002] Robots are gradually being used in medical surgeries because of their high precision. At present, many rigid arms are used in medical surgeries. Such arms are simple in structure and easy to operate and control. Traditional rigid structure robots can achieve target requirements for specific tasks, but rigid robots are mostly realized by rods and various kinematic pairs, and their flexibility is poor. Due to the complex internal environment of the human body, rigid arms are limited by their structural characteristics and are not flexible enough, and the space for movement in the human body is limited. In nature, such as octopus arms and snakes, they have good obstacle avoidance capabilities and large moving space. By imitating the characteristics of these creatures, we can conceive of a flexible and bendable continuum flexible manipulator arm that clamps the operating instrument at the end. This robot can be flexibly bent to adapt to the complex internal environment.

[0003] Existing flexible machines include snake-like robots and elephant-trunk robots.

[0004] The existing snake-like robot consists of two parts: a flexible body and a main controller. The flexible body consists of a spring, a bracket, a drive device and a top cover. Multiple sections of the flexible body are connected and can bend in all directions. The main controller placed at the tail end of the robot controls the control panel at the end of each flexible body to realize the movement of each flexible body. It has a good load-bearing capacity. However, this robot that uses a main controller to control the flexible body must be controlled at a short distance during medical surgery because the main controller and the flexible body are integrated into one body and are limited by the structure. This makes its operation flexibility poor and it is easy to collide with the patient during the operation, which is highly dangerous.

[0005] Existing elephant trunk robots use magnetorheological fluid technology. The outer layer is composed of multiple springs connected in series, with a spine in the center. The spine is filled with a special liquid that changes its shape with the magnetic field. When the robot is powered on, the outer ring causes the internal magnetic field to change, and the special liquid in the robot's catheter realizes liquid-solid conversion, thereby driving the robot to bend, solving the problem of traditional rigid structure robots having difficulty grasping irregularly shaped objects. However, this method of solid-liquid conversion to achieve low control accuracy of the robot. If there is an error in the liquid-solid conversion of the special liquid in the spine, it will directly lead to inadequate or excessive operation of the robot, and the consequences will be disastrous.

[0006] Based on the above statements, there is an urgent need to propose a precise, flexible and reliable operation, fast response speed, and high real-time robot and robot control method for surgical operations to adapt to the narrow working environment of surgical operations and achieve precise control to ensure that when the doctor operates the robot, it will not cause unexpected movement of the robot, thereby avoiding accidental contact between the robot and the human body during the operation, causing damage to the patient. Summary of the invention

[0007] The present invention proposes a surgical master-slave flexible continuum robot with high control accuracy, flexible operation and fast response speed and a control method thereof; the technical solution of the present invention is as follows:

[0008] Solution 1:

[0009] A master-slave flexible continuum robot for surgical operations, comprising a robot slave hand and a robot master hand, wherein the robot master hand is connected to a wire drive unit via a driver, and the wire drive unit is used to control the movement of the robot slave hand;

[0010] The robot slave comprises a first slave component, a second slave component and a third slave component connected end to end, wherein the first slave component, the second slave component and the third slave component are wire-driven, and four ropes are connected to the ends of the corresponding components, and the freedom degree of the first slave component, the second slave component and the third slave component is driven to change by changing the length of the ropes;

[0011] The robot main hand comprises three straight rods with the same structure and variable lengths, which are connected in sequence, and a posture sensor is installed in each straight rod.

[0012] Preferably: the first slave member comprises a top unit section and four first middle unit sections, and the top unit section and the four first middle unit sections are fitted and installed via a spring 4;

[0013] The second slave member includes five second intermediate unit sections, the five second intermediate unit sections are matched in sequence through springs, and the first intermediate unit section and the second intermediate unit section located at the matching position of the first slave member and the second slave member are matched through the spring;

[0014] The third slave component includes four third intermediate unit sections and a bottom unit section. The bottom unit section and the four third intermediate unit sections are fitted together by springs. The second intermediate unit section and the third intermediate unit section located at the fitting place between the second slave component and the third slave component are fitted together by springs.

[0015] Preferably: the top unit section and the bottom unit section have the same structure, both comprising a disc and a cone mounting portion provided at the center of one end surface of the disc;

[0016] The first intermediate unit section, the second intermediate unit section and the third intermediate unit section have the same structure, and all include a first disk and a first cone mounting portion arranged at the center of the end surfaces on both sides of the first disk.

[0017] Preferably: the straight rod comprises an outer shell and a telescopic rod, one end of the outer shell has an opening, the other end of the outer shell has a socket portion, a long hole is processed on the side wall of the outer shell, the telescopic rod is a round rod, the outer side wall of the telescopic rod has a protrusion, the telescopic rod is installed in the outer shell, and the protrusion on the telescopic rod is installed in cooperation with the long hole on the outer shell.

[0018] Option 2:

[0019] The control method of a master-slave flexible continuum robot for surgical operations aims to control the robot slave by controlling the change of the rope. The slave of the master-slave robot includes a first slave component, a second slave component and a third slave component, and the three components are connected end to end. Each component is composed of multiple unit sections. There are springs between the components as supports with certain flexibility. Each component is driven by a wire, and four ropes are connected at the end of the component. By changing the length of the rope, the change of the two degrees of freedom of the rod deflection and bending is driven. The two degrees of freedom can be described by two data of deflection angle and bending angle. Therefore, the three components from the top to the end of the robot have 4, 8, and 12 ropes passing through them respectively, and a total of 6 degrees of freedom are operated. The posture formed by the bending of each component can be approximated as an arc, which can be bent into an arc of any shape.

[0020] The control module obtains the sensor data from the master hand end, and obtains the required changes in the deflection angle and bending angle of each component of the slave hand end through calculation, thereby obtaining the changes in the lengths of the four self-driving lines required to drive each slave hand component.

[0021] Since the driving wire at the upper end passes through the components at the lower end, the movement of the components at the lower end will affect the change in the length of the wire at the upper end. By decoupling and calculating the multi-end motion, 12 independent changes in wire length can be obtained. And 12 motors corresponding to the ropes are driven to achieve the length change.

[0022] The specific method of controlling the length change of the rope to realize the slave control of the robot includes the following steps:

[0023] Step 1: Each end attitude sensor of the three robot main hands transmits the XYZ fixed angle relative to the world coordinate system to represent the coordinate system of the end attitude of each main hand component. Let the attitude sensor angles be ɑ1, β1, γ1 and ɑ2, β2, γ2 and ɑ3, β3, γ3 respectively. Let the 3*3 rotation matrix of the XYZ fixed angle of each main hand component end coordinate system relative to its own bottom coordinate system be R m, and the 3*3 rotation matrix of the end coordinate system relative to the fixed world coordinate system is R, and the 3*3 rotation matrix expressed by the deflection angle and the bending angle is R n ;

[0024] Step 2: According to the rotation matrix, use each set of Euler angles to obtain the deflection angle and bending angle θ′1 representing the deflection and bending. and θ′2, and θ′3, The 3*3 rotation matrix R1 (R m1 ) and the 3*3 rotation matrix R of the deflection angle and bending angle n1 Equal, the bending angle and deflection angle θ′1 at the end of the main hand component are obtained.

[0025]

[0026]

[0027]

[0028] In the formula, c represents the Cos cosine function, s represents the Sin sine function, and a 11 、a 12 、a 13 、a 21 、a 22 、a 23 、a 31 、a 32 、a 33 Corresponding to = rotation matrix R n1 Each element in, for example, α 11 =cα1cβ1;

[0029] Since the parameters of the attitude sensor are obtained relative to the fixed world coordinate system, and the coordinate system of the second component end is relative to its own bottom coordinate system, coordinate transformation is required to obtain R m2 ;

[0030]

[0031] R m2 R1=R2

[0032]

[0033] Solve for R m2 After that, set Similarly, the first component, with the 3*3 rotation matrix R expressed by the deflection angle and bending angle n2 Equal, the bending angle θ′2 and the deflection angle are obtained

[0034]

[0035] Similarly, we can obtain θ′3 and

[0036]

[0037] Since the master hand component is equivalent to the chord of the arc formed by the corresponding component of the slave hand, the deflection angle of the slave hand component is equal to that of the master hand component, that is, The bending angle is twice the bending angle of the main hand component, that is, θ i =2θ′ i ;

[0038] Step 3: Assume that the thickness of each slave component disk is h, the diameter is d, the original length in the vertical state is 1, and each component is composed of n disks. According to the deflection angle and bending angle of each component that have been obtained, the change in the length of the driving rope required for each component is obtained. Assume dij is the required change in the jth driving rope (j=1, 2, 3, 4) of the i-th component (i=1, 2, 3), then:

[0039]

[0040] Then, the effect of the change in the lower rope length on the change in the upper rope length is coupled to obtain the actual change in the lengths of the 12 ropes:

[0041]

[0042] The beneficial effects of the present invention are embodied in:

[0043] A master-slave isomorphic continuum robot mainly consists of a slave hand, a master hand and a controller. The doctor controls the master hand, the displacement sensor collects parameter information, and the controller controls the slave hand to reproduce the master hand's movements. Among them, the master hand is passive and is bent into the required shape by the doctor, while the slave hand is active and is controlled by a motor. Due to the high degree of freedom of the continuum robot, there may be multiple solutions for the path to the same target point. At the same time, directly controlling the robot by a computer is too abstract. The more degrees of freedom, the more kinematic inverse solutions, the more complex the solution, and the real-time performance is not high. The master-slave operation can avoid this problem. The slave hand no longer needs a computer to obtain a path solution, but only needs to accurately reproduce the operation of the master hand, with fast response speed and high real-time performance.

[0044] The slave hand adopts a more compact design to adapt to the narrow operating environment of surgical operations; a master-slave heterogeneous design method is proposed to solve the problem that the master hand is difficult to fix and other components of the slave hand are prone to accidental movement when the doctor operates, so as to avoid accidental contact between the non-surgical operating part of the slave hand and the human body during the operation; the master hand end uses a posture sensor instead of a position sensor to record the deformation of the master hand, so that the slave hand can track the movement direction of the master hand more accurately; the length of each straight rod at the master hand end changes with the direction in which the doctor operates the straight rod. On the basis of the slave hand reproducing the deflection and bending direction of the master hand, the length of the master hand straight rod changes in real time to achieve that the end position of each component of the master hand is exactly the same as the end position of each straight rod of the slave hand, so that only the end point of the master hand can be operated, and the end point of the slave hand can reach the same position, making the doctor's operation more intuitive and convenient.

[0045] The robot and control method of the present invention have the advantages of high precision, flexible and reliable operation, fast response speed and high real-time performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is the slave hand of the master-slave flexible continuum robot for surgical operations;

[0047] Figure 2 This is a schematic diagram of the robot's hand in a bent state;

[0048] Figure 3 It is a stereogram of the apical unit segment;

[0049] Figure 4 is a stereogram of the first intermediate unit section;

[0050] Figure 5 is a stereogram of the second intermediate unit segment;

[0051] Figure 6 It is a stereogram of the third intermediate unit section;

[0052] Figure 7 It is a stereogram of the bottom unit section;

[0053] Figure 8 This is a stereogram of the robot's main hand;

[0054] Fig. 9 is a stereogram of the outer shell;

[0055] Fig.10 is a stereogram of a telescopic rod;

[0056] Fig.11 It is the relationship diagram between deflection, bending angle and XYZ fixed angle;

[0057] Fig.12 It is a diagram of physical quantities from hand joints;

[0058] Fig.13 It is the physical quantity identification diagram of the main hand joint;

[0059] Fig.14 It is the flow chart of slave control;

[0060] Fig.15 It is the master hand control flow chart;

[0061] In the figure, 1-robot slave hand, 2-robot master hand, 3-rope, 4-spring, 5-straight rod, 11-first slave hand component, 12-second slave hand component, 13-third slave hand component, 111-top unit section, 112-first intermediate unit section, 113-second intermediate unit section, 114-third intermediate unit section, 115-bottom unit section, 1111-disc, 1112-cone mounting part, 1121-first disc, 1122-first cone mounting part, 51-outer shell, 52-telescopic rod, 53-sleeve connection part, 54-long hole, 55-protrusion. DETAILED DESCRIPTION

[0062] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work. Specific implementation method one:

[0064] The slave of this master-slave robot is Figure 1 As shown, three components are connected end to end, specifically a first slave component 11, a second slave component 12 and a third slave component 13, and the three components are connected end to end. Figure 1-Figure 7 The robot is shown as consisting of a top unit segment 111, four first intermediate unit segments 112, five second intermediate unit segments 113, four third intermediate unit segments 114 and a bottom unit segment 115, with a total of 15 joints. There are springs 4 between the components as supports with a certain degree of flexibility. Each component is driven by a wire, and is connected to the end of the component by four ropes. The changes in the two degrees of freedom of deflection and bending of the rod are driven by changing the length of the rope. These two degrees of freedom can be described by two data, the deflection angle and the bending angle. Therefore, there are 4, 8, and 12 ropes passing through the three components from the top to the end of the robot, respectively, and a total of 6 degrees of freedom are operated. Since there are 4, 8, and 12 ropes passing through the three components from the top to the end of the robot, respectively, threading holes (such as Figure 4-Figure 7As shown), the threading hole is used to pass the rope 3. As the number of ropes 3 increases, the number of holes on the corresponding unit nodes also increases. For example, four threading holes are processed on the first middle unit node 112, eight threading holes are processed on the second middle unit node 113, and twelve threading holes are processed on the third middle unit node 114 and the bottom unit node 115;

[0065] The posture formed by the bending of each component can be approximated as an arc, and can be bent into an arc of any shape.

[0066] The master-slave flexible continuum robot for surgical operations in this embodiment also includes a control module, which obtains sensor data from the master hand end, calculates the changes in the deflection angle and bending angle required for each component of the slave hand end, and thus obtains the changes in the length of the four self-driving lines required to drive each component. Since the driving line at the upper end will pass through the component at the lower end, the movement of the lower end component will affect the change in the length of the upper end. By decoupling and calculating the multi-end motion, 12 independent changes in the length of the line can be obtained. And drive 12 motors corresponding to the ropes one by one to achieve length changes.

[0067] The master-slave flexible continuum robot for surgical operations in this embodiment also includes a wire drive unit, which receives instructions from the control module and is used to control the movement of the robot's slave hand 1. The wire drive unit pulls or loosens the rope 3 to generate slave hand movements; in this embodiment, the wire drive unit can be a DC motor, a servo motor, a stepper motor, etc., but the present invention is not limited to this.

[0068] A master-slave flexible continuum robot for surgical operations comprises a robot slave hand 1 and a robot master hand 2, wherein the robot master hand 2 is connected to a wire drive unit via a driver, and the wire drive unit is used to control the movement of the robot slave hand 1;

[0069] The robot slave 1 comprises a first slave member 11, a second slave member 12 and a third slave member 13 connected end to end. The first slave member 11, the second slave member 12 and the third slave member 13 are wire-driven, and are connected to the ends of the corresponding members by four ropes 3. The degree of freedom of the first slave member 11, the second slave member 12 and the third slave member 13 is driven by changing the length of the ropes 3.

[0070] The robot main hand 2 includes three straight rods 5 of the same structure and variable length, which are connected in sequence, and a posture sensor is installed in each straight rod 5.

[0071] Preferably, the first slave member 11 comprises a top unit section 111 and four first intermediate unit sections 112, and the top unit section 111 and the four first intermediate unit sections 112 are fitted and installed via a spring 4;

[0072] The second slave member 12 includes five second intermediate unit sections 113, and the five second intermediate unit sections 113 are matched with each other in sequence through the spring 4. The first intermediate unit section 112 and the second intermediate unit section 113 located at the matching position of the first slave member 11 and the second slave member 12 are matched with each other through the spring 4.

[0073] The third slave component 13 includes four third intermediate unit segments 114 and a bottom unit segment 115. The bottom unit segment 115 and the four third intermediate unit segments 114 are fitted together by a spring 4. The second intermediate unit segment 113 and the third intermediate unit segment 114 located at the fitting position of the second slave component 12 and the third slave component 13 are fitted together by a spring 4.

[0074] Preferably, the top unit section 111 and the bottom unit section 115 have the same structure, both comprising a disk 1111 and a cone mounting portion 1112 disposed at the center of one end surface of the disk 1111;

[0075] The first intermediate unit segment 112 , the second intermediate unit segment 113 and the third intermediate unit segment 114 have the same structure, and all include a first disk 1121 and a first cone mounting portion 1122 disposed at the center of the end surfaces on both sides of the first disk 1121 .

[0076] Preferably, the straight rod 5 comprises an outer shell 51 and a telescopic rod 52, one end of the outer shell 51 has an opening 56, the other end of the outer shell 51 has a sleeve portion 53, a side wall of the outer shell 51 is processed with a long hole 54, the telescopic rod 52 is a round rod, and the outer side wall of the telescopic rod 52 has a protrusion 55, the telescopic rod 52 is slidably installed in the outer shell 51, and the protrusion 55 on the telescopic rod 52 is installed in cooperation with the long hole 54 on the outer shell 51, as shown in FIG. Fig.10 As shown, the posture sensor is installed on the left end surface of the telescopic rod 52.

[0077] From the structure and control method of the hand

[0078] The master-slave robot includes a master hand, a control module, a driving unit and a slave hand. The control module obtains sensor data from the master hand end, obtains the change in deflection angle and bending angle required for each component of the slave hand end by calculation, thereby obtaining the change in length of the four self-driving lines required to drive each component, and controls the slave hand to make corresponding actions by adjusting the length of the driving line through the driving unit. In this embodiment, the control algorithm of the slave hand is:

[0079] Each end attitude sensor of the three main hand components transmits the XYZ fixed angle relative to the world coordinate system to represent the coordinate system of the end attitude of each component. The attitude sensor angles are ɑ1, β1, γ1 and ɑ2, β2, γ2 and ɑ3, β3, γ3. The 3*3 rotation matrix of the XYZ fixed angle of each component end coordinate system relative to its own bottom coordinate system is R m , and the 3*3 rotation matrix of the end coordinate system relative to the fixed world coordinate system is R, and the 3*3 rotation matrix expressed by the deflection angle and the bending angle is R n .

[0080] Depend on Fig.11 As shown, according to the rotation matrix, each set of Euler angles can be used to obtain the deflection angle and bending angle θ′1, and θ′2, and θ′3, The 3*3 rotation matrix R1 (R m1 ) and the 3*3 rotation matrix R of the deflection angle and bending angle n1 The bending angle and deflection angle θ′1 at the end of the main hand component are equal.

[0081]

[0082]

[0083]

[0084] Since the parameters of the attitude sensor are obtained relative to the fixed world coordinate system, and the coordinate system of the second component end is relative to its own bottom coordinate system, coordinate transformation is required to obtain R m2 .

[0085]

[0086] R m2 R1=R2

[0087]

[0088] Solve for R m2 After that, set Similarly, the first component, with the 3*3 rotation matrix R expressed by the deflection angle and bending angle n2 Equal, the bending angle θ′2 and the deflection angle are obtained

[0089]

[0090] Similarly, we can obtain θ′3 and

[0091]

[0092] Since the master hand component is equivalent to the chord of the arc formed by the corresponding component of the slave hand, the deflection angle of the slave hand component is equal to that of the master hand component, that is, The bending angle is twice the bending angle of the main hand component, that is, θ i =2θ′ i .

[0093] like Fig.12 As shown, suppose the thickness of each slave component disk is h, the diameter is d, the original length in the vertical state is l, and each component is composed of n disks. According to the deflection angle and bending angle of each component that have been obtained, the change in the length of the driving rope required for each component can be obtained. Let dij be the required change (not the actual change, it is the actual change after coupling) of the jth driving rope (j=1, 2, 3, 4) of the i-th component (i=1, 2, 3).

[0094]

[0095] By coupling the effect of the change in the lower rope length on the change in the upper rope length, the actual change in the length of each of the 12 ropes can be obtained.

[0096]

[0097] like Fig.14 As shown, the slave hand control process is as follows: first, the doctor operates to change the shape of the master hand, and obtains the data of the posture sensor installed at the master hand end through the control module, specifically, the parameters of the three posture sensors 1 (the parameters of the master hand posture sensor 1, the parameters of the master hand posture sensor 2, and the parameters of the master hand posture sensor 3) are obtained respectively, and then the bending angle and deflection angle required for the slave hand component 1, the bending angle and deflection angle required for the slave hand component 2, and the bending angle and deflection angle required for the slave hand component 3 are calculated, and then the length of the driving line (rope 3) required for the slave hand component 1 to reach the corresponding posture is calculated respectively. The length change of the driving wire (rope 3) required for the slave hand member 2 to reach the corresponding posture is calculated, and the length change of the driving wire (rope 3) required for the slave hand member 3 to reach the corresponding posture is calculated. Subsequently, the independent change of the driving wire length of the slave hand member 1 is obtained by decoupling calculation, the independent change of the driving wire length of the slave hand member 2 is obtained by decoupling calculation, and the independent change of the driving wire length of the slave hand member 3 is obtained by decoupling calculation. Finally, the three independent changes of the driving wire length are sent to the driving part, and the corresponding wire length change is realized by the driving motor to complete the slave control.

[0098] The structure and control method of the main hand

[0099] The robot's main hand Figure 8-10 As shown, three isomorphic and length-variable straight rods are connected in sequence, and the straight rod 5 includes an outer shell 51 and a telescopic rod 52. One end of the outer shell 51 has an opening 56, and the other end of the outer shell 51 has a sleeve portion 53. A long hole 54 is processed on the side wall of the outer shell 51. The telescopic rod 52 is a round rod, and a protrusion 55 is provided on the outer side wall of the telescopic rod 52. The telescopic rod 52 is slidably installed in the outer shell 51, and the protrusion 55 on the telescopic rod 52 is installed in cooperation with the long hole 54 on the outer shell 51.

[0100] The number of adjacent straight rods 5 is three, and the telescopic rods 52 in the adjacent straight rods 5 are installed in the sleeve portion 53 of the outer shell 51 to achieve sequential connection;

[0101] Each straight rod of the master hand corresponds to each member of the slave hand. At the end of each straight rod, a posture sensor is installed, such as Fig.10 As shown, the posture sensor is installed on the left end face of the telescopic rod 52. The direction of the sensor is upward along the previous straight rod, and the real-time direction caused by the operator rotating each straight rod is read in real time, and the direction data is transmitted to the control module. Each posture sensor determines the deflection angle and bending angle of the arc formed by each component at the slave end. The variable length straight rods of the master hand are used as virtual chords of the arc corresponding to the slave hand component. As the arc changes, the length of the straight rod is continuously changed so that it can follow the change of the chord length of the arc corresponding to the posture sensor, so that the end point of each component of the slave hand can completely reproduce the position and posture of the end point of each straight rod of the master hand in Cartesian space. The required length change of the straight rod is obtained by calculation in the control module, and the length change is realized by the motor contained in each straight rod.

[0102] From the above, we can know that θ has been obtained i , like Fig.13 As shown, assuming that the length of each rod of the master hand is f, since the master hand needs to adjust its length in real time to align the end point with the end point of the slave hand, the required change length of the i-th rod (i = 1, 2, 3) can be obtained according to the bending angle, as shown in the following figure:

[0103]

[0104] like Fig.15 As shown in FIG. 1 , the master hand control process is as follows: first, the doctor operates to change the shape of the master hand, and then obtains the parameters of the three master hand posture sensors, specifically the parameters of the master hand posture sensor 1, the parameters of the master hand posture sensor 2, and the parameters of the master hand posture sensor 3, and then calculates the required bending angle of the slave hand component 1. and the deflection angle θ1, calculate the required bending angle from the hand member 2 and the deflection angle θ2, calculate the required bending angle of the hand member 3 and deflection angle θ3; finally, calculate the rod length change required for the end point of the main hand straight rod 1 to track the end point of the slave hand component 1, the rod length change required for the end point of the main hand straight rod 2 to track the end point of the slave hand component 2, and the rod length change required for the end point of the main hand straight rod 3 to track the end point of the slave hand component 3, and drive the motor to achieve the corresponding rod length change.

[0105] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solution of the present invention should be included in the scope of protection of the present invention.

Claims

1. A master-slave flexible continuum robot for surgical operations, characterized by: It includes a robot slave hand (1) and a robot master hand (2); The robot slave (1) comprises a first slave component (11), a second slave component (12) and a third slave component (13) connected end to end, wherein the first slave component (11), the second slave component (12) and the third slave component (13) are driven by wires, and four ropes (3) are connected to the ends of the corresponding components, and the deflection and bending of the first slave component (11), the second slave component (12) and the third slave component (13) are driven by changing the length of the ropes (3); The robot main hand (2) comprises three straight rods (5) of the same structure and variable length, which are connected in sequence, and each straight rod (5) is equipped with a posture sensor; The first slave component (11) comprises a top unit section (111) and four first middle unit sections (112), and the top unit section (111) and the four first middle unit sections (112) are matched and installed via a spring (4); The second slave member (12) includes five second intermediate unit sections (113), and the five second intermediate unit sections (113) are matched in sequence through springs (4); The third slave member (13) comprises four third intermediate unit sections (114) and a bottom unit section (115), and the bottom unit section (115) and the four third intermediate unit sections (114) are matched and installed via a spring (4); The top unit section (111) and the bottom unit section (115) have the same structure, both comprising a disk (1111) and a cone mounting portion (1112) disposed at the center of one end surface of the disk (1111); The first intermediate unit section (112), the second intermediate unit section (113) and the third intermediate unit section (114) have the same structure, and all include a first disk (1121) and a first cone mounting portion (1122) arranged at the center of the end surfaces on both sides of the first disk (1121).

2. The master-slave flexible continuum robot for surgical operation according to claim 1, characterized in that: The straight rod (5) comprises an outer shell (51) and a telescopic rod (52). One end of the outer shell (51) has an opening 56, and the other end of the outer shell (51) has a sleeve portion (53). A long hole (54) is processed on the side wall of the outer shell (51). The telescopic rod (52) is a round rod. The outer side wall of the telescopic rod (52) has a protrusion (55). The telescopic rod (52) is installed in the outer shell (51), and the protrusion (55) on the telescopic rod (52) is installed in cooperation with the long hole (54) on the outer shell (51).

3. A control method for a master-slave flexible continuum robot for surgical operations, wherein the slave of the master-slave robot comprises a first slave component (11), a second slave component (12) and a third slave component (13), the three components being connected end to end, each component being composed of a plurality of unit sections, springs being arranged between the components as supports with a certain degree of flexibility, each component being respectively driven by a wire, connected at the end of the component by four ropes, and the changes in the two degrees of freedom of deflection and bending of the rod being driven by changing the length of the rope, characterized in that: The following steps are involved: Step 1: Each end posture sensor of the three robot main hands (2) transmits an XYZ fixed angle relative to the world coordinate system to represent the coordinate system of the end posture of each robot main hand (2). Suppose the posture sensor angles are ɑ1, β1, γ1 and ɑ2, β2, γ2 and ɑ3, β3, γ3 respectively. Suppose the 3*3 rotation matrix of the XYZ fixed angle of each robot main hand (2) end coordinate system relative to its own bottom coordinate system is R m , and the 3*3 rotation matrix of the end coordinate system relative to the fixed world coordinate system is R, and the 3*3 rotation matrix expressed by the deflection angle and the bending angle is R n ; Step 2: According to the rotation matrix, use each set of Euler angles to obtain the deflection angle and bending angle θ1′ representing the deflection and bending. and θ2′, and θ3′, The 3*3 rotation matrix R1 (R m1 ) and the 3*3 rotation matrix R of the deflection angle and bending angle n1 equal, and the bending angle and deflection angle θ1′ at the end of the robot's main hand (2) are obtained. In the formula, c represents the Cos cosine function, s represents the Sin sine function, and ɑ 11 、ɑ 12 、ɑ 13 、ɑ 21 、ɑ 22 、ɑ 23 、ɑ 31 、ɑ 32 、ɑ 33 Corresponding to the rotation matrix R n1 Each element in Since the parameters of the posture sensor are obtained relative to the fixed world coordinate system, and the coordinate system of the end of the second slave hand component (12) is relative to the coordinate system of the third slave hand component (13), a coordinate transformation is required to obtain R m2 ; R m2 R1=R2 Solve for R m2 After that, set Similarly, the first slave component (11) is a 3*3 rotation matrix R expressed by the deflection angle and the bending angle. n2 Equal, the bending angle θ2′ and the deflection angle Similarly, we can obtain θ3′ and Since the robot master hand (2) is equivalent to the chord of the arc formed by the robot slave hand (1) corresponding to the first slave hand component (11), the second slave hand component (12) and the third slave hand component (13), the deflection angles of the robot slave hand (1) and the robot master hand (2) are equal, that is, The bending angle is twice the bending angle of the robot's main hand (2), that is, θ i =2θ i ′; Step 3: Assume that the thickness of the disk in the first slave member (11), the second slave member (12) and the third slave member (13) is h, the diameter is d, and the original length in the vertical state is l, and the first slave member (11), the second slave member (12) and the third slave member (13) are composed of n disks. According to the deflection angle and bending angle of the first slave member (11), the second slave member (12) and the third slave member (13) that have been obtained, the change in the length of the driving rope required for the first slave member (11), the second slave member (12) and the third slave member (13) is obtained. Assume that dij is the required change in the jth driving rope of the i-th member, i=1, 2, 3, j=1, 2, 3, 4, then: Then, the effect of the change in the lower rope length on the change in the upper rope length is coupled to obtain the actual change in the lengths of the 12 ropes:

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