Continuum robot macro-micro motion device and method based on eccentric mechanism

Abstract

The application provides a continuum robot macro-micro motion device and method based on eccentric mechanism, which comprises a plurality of unit bodies connected in sequence, any unit body comprising a rigid section and a bendable section; the rigid section of the unit body is provided with a positioning block, the middle part of the positioning block is formed with a central cavity, and the positioning block is further provided with an eccentric macro drive cavity and an eccentric micro drive cavity; a drive rope is arranged in the macro drive cavity, and a bendable fiber with an eccentric cavity is arranged in the micro drive cavity. The motion ability of the robot is enhanced by rotating the bendable fiber with the eccentric cavity, two hot-drawing polymer fibers with eccentric inner cavities are inserted into the micro drive cavity of the continuum robot, the macro motion of the robot is completed by stretching the drive rope, the micro motion is provided by the rotation of the eccentrically arranged fiber, and the basic principle of the micro motion is to rely on the slight change of the neutral axis of the continuum robot.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of robot technology, in particular to a continuum robot macro-micro motion device and method based on eccentric mechanism. BACKGROUND

[0002] Continuum robots have attracted more and more attention in minimally invasive surgery due to their dexterity and flexibility. Its compliant skeleton can naturally conform to environmental obstacles, enabling the robot to pass through winding paths to reach the deep part of the human body cavity.

[0003] The existing patent application with the publication number CN113023659B discloses an XY macro-micro motion platform and its end feedback method. The XY macro-micro motion platform includes a fine adjustment assembly, a macro drive assembly, and a position detection device. The macro drive assembly includes an X-direction macro drive unit, a Y-direction macro drive unit, an X-direction plate, and a Y-direction plate. The position detection device is used to obtain the position of itself on the X-axis and Y-axis. The present XY macro-micro motion platform adopts an XY macro-micro decoupling mode. The macro motion component and the micro motion component on each axis are provided with a decoupling arrangement. On this basis, decoupling arrangement is performed between X-direction motion and Y-direction motion to make the entire system form a common horizontal plane on the XY axis and form a decoupling arrangement between the macro and the micro.

[0004] The existing technology adopts an XY macro-micro decoupling mode. The macro motion component and the micro motion component on each axis are provided with a decoupling arrangement. The decoupling mode of the present invention requires multiple motion pairs, and the overall structure size is large, which cannot be applied to the macro-micro motion of continuum robots. SUMMARY

[0005] In view of the defects in the prior art, the purpose of the present application is to provide a continuum robot macro-micro motion device and method based on eccentric mechanism.

[0006] According to the present application, a continuum robot macro-micro motion device based on eccentric mechanism is provided, which includes a plurality of unit bodies connected in sequence. Any unit body includes a rigid segment and a bendable segment. The rigid segment of the unit body is installed with a positioning block. The center part of the positioning block forms a central cavity. The positioning block is also provided with an eccentric macro drive cavity and an eccentric micro drive cavity. A drive rope is arranged in the macro drive cavity. A bendable fiber with an eccentric cavity is arranged in the micro drive cavity.

[0007] Preferably, the micro drive cavity is provided with two, and the included angle between the two micro drive cavities and the center line of the central cavity on the positioning block is ninety degrees.

[0008] Preferably, the unit body is a nickel-titanium tube with symmetrical slotted structure, the unit body comprises two rigid segments and two bendable segments, the two bendable segments are arranged between the two rigid segments, and the two bendable segments are oppositely arranged.

[0009] Preferably, the rigid segments and the bendable segments are alternately connected, one rigid segment has two adjacent bendable segments, one of the bendable segments can bend in the vertical direction, and the other bendable segment can bend in the horizontal direction.

[0010] Preferably, the positioning block is in the shape of a circular sheet, and the positioning block is coaxially arranged in the rigid segment of the unit body.

[0011] Preferably, the diameter of the bendable fiber with the eccentric cavity is sub-millimeter level.

[0012] According to the macro-micro motion method of a continuum robot based on the eccentric mechanism provided by the application, the motion method satisfies the following kinematic model:

[0013] For a unit body, according to the material geometric deformation condition, the balance equation of the unit body at the cross section can be obtained as:

[0014]

[0015] E i is the Young's modulus of the i-th region of the cross section, l i is the distance from the micro-element dA i to the neutral axis of the cross section, A i is the area of the i-th region of the cross section.

[0016] If the robot bends in the horizontal direction, it can be expressed as:

[0017] E m A1(y1-y)+E r A 21 (y 21 -y)-E r A 22 (y 22 -y)+E r A 31 (y 31 -y)-E r A 32 (y 32 -y)=0

[0018] E m and E r are the Young's moduli of the robot body and the polymer fiber rod respectively; A1, A 21 , A 22 , A31 and A 32 are S1, S 2-1 , S 2-2 , S 3-1 and S 3-2 , respectively; y1, y 21 , y 22 , y 31 and y 32 are the neutral axis positions of S1, S 2-1 , S 2-2 , S 3-1 and S 3-2 , respectively; y is the neutral axis of the cross section, and it can be derived that:

[0019]

[0020] When the robot is bent in the vertical direction, the neutral axis of the cross section can be calculated as:

[0021]

[0022] where A4 is the area of S4; z 21 , z 22 , z 31 , z 32 and z4 are the neutral axis positions of S 2-1 , S 2-2 , S 3-1 , S 3-2 and S4, respectively; z is the neutral axis of the cross section;

[0023] where y 22 , y 32 , z 22 and z 32 will change with the rotation of the fiber, as shown in the following formula:

[0024]

[0025] where d e is the distance from the center of the eccentric lumen of the fiber to the center of the fiber, d is the distance between the center of the fiber and the center of the robot, q1 and q2 are the rotation angles of the two fibers, and in addition, the positive rotation direction of the two fibers is counterclockwise;

[0026] The bending moments and curvatures of the two bendable parts of each unit body in the horizontal and vertical directions can be represented as:

[0027] M1 = κ y EI y = -(y + d c )T1

[0028] M2 = -κ z EIz = zT2

[0029] where M1 and M2 are the bending moments along horizontal and vertical directions, κ y and κ z are the neutral axis curvatures along horizontal and vertical directions, EI y and EI z are the bending stiffnesses along horizontal and vertical directions, T1 and T2 are the tensions of the driving ropes in the two bendable sections, d c is the distance between the driving ropes and the center axis of the robot.

[0030] Preferably, for the convenience of solution, it is assumed that the length variation of the driving ropes corresponding to each unit cell is the same; in the same unit cell, it is assumed that the tension along the length direction of the driving ropes is the same; the influence of the rotation of the two fibers on the bending stiffness of the continuum robot is ignored;

[0031] Since the materials and sizes of the two bendable sections in the same unit cell are the same, the bending stiffnesses along horizontal and vertical directions can be considered to be equal, i.e. EI y = EI z .

[0032]

[0033] When the driving ropes are pulled, the angles of bending in each bending direction are:

[0034]

[0035] where h is the length of each bendable section, θ y and θ z are the bending angles along horizontal and vertical directions, dq 31 and dq 32 are the length variations of the driving ropes in each unit cell due to horizontal bending and vertical bending, q3 / n = dq 31 + dq 32 , q3 is the total length variation of the driving ropes, and n is the total number of unit cells.

[0036] When q3 is known, θ y , θ z , κ y and κ z can be calculated.

[0037] Preferably, the forward kinematics of each unit cell can be described as:

[0038]

[0039]

[0040]

[0041] P1 = [sin(θ y ), -(1 - cos(θ y )), 0] T / κ y , P2 = [h, 0, 0] T ,

[0042] P3 = [sin(θ z ), 0, -(1 - cos(θ z ))] T / κ z , and P4 = [h, 0, 0] T .

[0043] Preferably, the forward kinematics of the robot can be represented as:

[0044]

[0045]

[0046] wherein, is the second transformation matrix of the robot base to the first unit body, is the second transformation matrix of the last unit body of the robot to the robot end, and are the translation vectors of and respectively.

[0047] Compared with the prior art, the present application has the beneficial effects as follows:

[0048] 1. The present application enhances the motion ability of the robot by rotating the bendable fiber with eccentric cavity, inserts two heat-drawing polymer fibers with eccentric inner cavity into the micro-drive cavity of the continuous robot, the macro-motion of the robot is completed by the stretching of the driving rope, the micro-motion is provided by the rotation of the eccentric arranged fiber, and the basic principle of the micro-motion is dependent on the small change of the neutral axis of the continuum robot. BRIEF DESCRIPTION OF DRAWINGS

[0049] Other characteristics, objects and advantages of the present application will become more apparent from the following detailed description of non-restrictive embodiments, made with reference to the attached drawings:

[0050] Figure 1 It is a schematic diagram of the overall structure of the continuum robot mainly embodied by the present application;

[0051] Figure 2 It is a principle diagram of the heat-drawing of the bendable fiber mainly embodied by the present application;

[0052] Figure 3 This invention primarily illustrates the cross-sectional view of the bendable segment of the robot bending in the horizontal direction;

[0053] Figure 4 This invention primarily illustrates the cross-sectional view of the bendable segment of the robot bending in the vertical direction;

[0054] Figure 5 This invention primarily illustrates the macroscopic motion trajectory of a continuum robot;

[0055] Figure 6 This invention primarily embodies the micro-motion trajectory diagram of a continuum robot.

[0056] As shown in the figure:

[0057] Unit 1

[0058] Positioning Block 2

[0059] Central cavity 3

[0060] Macro-driven cavity 4

[0061] Micro-drive cavity 5 Detailed Implementation

[0062] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0063] Example One

[0064] like Figure 1 and Figure 2 As shown, a continuous robot macro-micro motion device based on an eccentric mechanism according to the present invention includes multiple sequentially connected unit bodies 1, each unit body 1 including a rigid segment and a flexible segment. A positioning block 2 is mounted on the rigid segment of the unit body 1, a central cavity 3 is formed in the middle of the positioning block 2, and an eccentric macro-drive cavity 4 and an eccentric micro-drive cavity 5 are also provided on the positioning block 2. A drive rope is disposed within the macro-drive cavity 4, and a flexible fiber with an eccentric cavity is disposed within the micro-drive cavity 5.

[0065] This application enhances the robot's motion capabilities by rotating flexible fibers with eccentric cavities. Two thermo-drawn polymer fibers with eccentric cavities are inserted into the micro-drive channels 5 of a continuous robot. The robot's macro-motion is accomplished by the stretching of the drive rope, while micro-motion is provided by the rotation of the eccentrically arranged fibers. The fundamental principle of micro-motion relies on minute changes in the neutral axis of the continuous robot.

[0066] The continuum robot is composed of multiple identical unit bodies 1, each of which includes two rigid segments and two bendable segments. Specifically, the unit body 1 is a nickel-titanium tube with a symmetrical cut groove structure, which includes two rigid segments and two bendable segments, both of which are arranged between the two rigid segments and are oppositely arranged. The main body of the continuum robot of the present application is formed by laser cutting of a nickel-titanium tube, which has a symmetrical groove. In this cut groove structure, the robot body is composed of multiple identical unit bodies 1, each of which includes two rigid segments and two bendable segments, each of which is composed of two beams. The two bendable segments can bend in the horizontal and vertical directions, respectively, and can provide two degrees of freedom of bending for the robot.

[0067] The rigid segments and the bendable segments are alternately connected, and one rigid segment has two adjacent bendable segments, one of which can bend in the vertical direction and the other of which can bend in the horizontal direction. Two micro-drive cavities 5 are provided, and the included angle between the two micro-drive cavities 5 and the center line of the center cavity 3 on the positioning block 2 is ninety degrees. The positioning block 2 is in the shape of a circular sheet, and the positioning block 2 is coaxially installed in the rigid segment of the unit body 1. When the positioning block 2 is assembled into the cut groove nickel-titanium tube, three eccentric cavities and a center cavity 3 will be formed. The center passage is used for medical intervention, and the smallest passage of the three eccentric cavities and the other two passages are respectively occupied by a driving rope and two bendable fibers with eccentric cavities. The robot has one bending degree of freedom for macro motion, which is driven by a rope. At the same time, two micro-motion degrees of freedom of the robot are realized by the rotation of the two bendable fibers.

[0068] The diameter of the bendable fiber with an eccentric cavity is sub-millimeter level. Two bendable fibers are inserted into the two eccentric cavities of the continuum robot, and each bendable fiber has an eccentric inner cavity. Since the diameter of the bendable fiber is sub-millimeter level, the eccentric inner cavity of the bendable fiber is difficult to be easily manufactured by traditional manufacturing processes. Therefore, a hot-drawing method is used to manufacture the fiber, as shown in Figure 2 When one fiber rotates around its own center axis, the position of the eccentric inner cavity of the fiber on the cross section of the robot changes. According to the theory of material mechanics, the neutral axis of the robot changes with the rotation of the fiber. Since the diameter and Young's modulus of the bendable fiber eccentric inner cavity are much smaller than those of the robot, the scale of the end motion of the robot caused by the rotation of the fiber is much smaller than that caused by the rope driving. Therefore, the rotation of the fiber can make the robot produce micro-motion. In the assembly process, the positioning block 2 and the fiber need to be assembled together first to achieve good alignment, and then assembled together into the robot body.

[0069] A macro-micro motion method of continuum robot based on eccentric mechanism is provided, which adopts the robot macro-micro motion device, and the motion method satisfies the following kinematic model:

[0070] For a unit body 1, according to the material geometric deformation condition, the balance equation of the unit body 1 at the cross section can be obtained as:

[0071]

[0072] Wherein, E i is the Young's modulus of the i-th area of the cross section, l i is the distance from the micro-element dA i to the neutral axis of the cross section, A i is the area of the i-th area of the cross section.

[0073] If the robot is bent in the horizontal direction, it can be expressed as:

[0074] E m A1(y1-y)+E r A 21 (y 21 -y)-E r A 22 (y 22 -y)+E r A 31 (y 31 -y)-E r A 32 (y 32 -y)=0

[0075] Wherein, E m and E r are the Young's modulus of the robot body and the polymer fiber rod respectively; A1, A 21 , A 22 , A 31 and A 32 are the areas of S1, S 2-1 , S 2-2 , S 3-1 and S 3-2 respectively; y1, y 21 , y 22 , y 31 and y 32 are the positions of the neutral axis of S1, S 2-1 , S 2-2 , S 3-1 and S 3-2 respectively; y is the neutral axis of the cross section, and it can be obtained that:

[0076]

[0077] When the robot bends in the vertical direction, the neutral axis of the cross section can be calculated as:

[0078]

[0079] where A4 is the area of S4; z 21 , z 22 , z 31 , z 32 and z4 are the neutral axis positions of S 2-1 , S 2-2 , S 3-1 , S 3-2 and S4, respectively; z is the neutral axis of the cross section;

[0080] where, y 22 , y 32 , z 22 and z 32 will change with the rotation of the fiber, as shown in the following formula:

[0081]

[0082] where d e is the distance from the center of the eccentric lumen of the fiber to the center of the fiber, d is the distance between the center of the fiber and the center of the robot, q1 and q2 are the rotation angles of the two fibers, and in addition, the positive rotation direction of the two fibers is counterclockwise.

[0083] The bending moment and curvature of the two bendable parts of each unit body 1 in the horizontal and vertical directions can be represented as:

[0084] M1 = κ y EI y = -(y + d c )T1

[0085] M2 = -κ z EI z = zT2

[0086] where M1 and M2 are the bending moments in the horizontal and vertical directions, respectively, κ y and κ z are the neutral axis curvatures in the horizontal and vertical directions, respectively, EI y and EI z are the bending rigidities in the horizontal and vertical directions, respectively, T1 and T2 are the tensions of the driving ropes in the two bendable parts, respectively, d c is the distance between the driving rope and the center axis of the robot.

[0087] For convenience, the length change of the driving cable corresponding to each unit 1 is assumed to be the same; in the same unit 1, the tension along the length of the driving cable is assumed to be the same; the influence of the rotation of the two fibers on the bending stiffness of the continuum robot is ignored;

[0088] Since the material and size of the two bendable parts in the same unit 1 are the same, the bending stiffness in the horizontal and vertical directions can be considered to be equal, i.e. EI y = EI z ;

[0089]

[0090] When the driving cable is pulled, the angle of bending in each bending direction is:

[0091]

[0092] where h is the length of each bendable segment, θ y and θ z are the bending angles in the horizontal and vertical directions, dq 31 and dq 32 are the length changes of the driving cable in each unit 1 due to horizontal bending and vertical bending, respectively, q3 / n = dq 31 + dq 32 , q3 is the total length change of the driving cable, and n is the total number of units 1.

[0093] When q3 is known, θ y , θ z , κ y and κ z can be calculated.

[0094] The forward kinematics of each unit 1 can be described as:

[0095]

[0096]

[0097]

[0098] where P1 = [sin(θ y ), -(1-cos(θ y )), 0] T / κ y , P2 = [h, 0, 0] T ,

[0099] P3 = [sin(θ z ), 0, -(1-cos(θ z ))]T / κ z ,andP4=[h,0,0] T 。

[0100] The forward kinematics of the robot can be expressed as:

[0101]

[0102]

[0103] wherein, is the second transformation matrix of the robot base to the first unit body 1, is the second transformation matrix of the last unit body 1 of the robot to the robot end, and are respectively and translation vectors.

[0104] Example Two

[0105] Based on embodiment one, according to the macro-micro motion device of the continuum robot based on the eccentric mechanism provided by the application, the continuum robot is composed of a plurality of same unit bodies 1, each unit body 1 comprising two rigid segments and two bendable segments, as shown in Figure 1 The rigid segments and the bendable segments are alternately connected, and one rigid segment has two adjacent bendable segments. One bendable segment can bend in the vertical direction, and the other bendable segment can bend in the horizontal direction.

[0106] For a unit body 1 of the robot, according to the material geometric deformation condition, the equilibrium equation at the cross section of the unit body 1 can be obtained as

[0107]

[0108] wherein E i is the Young's modulus of the i-th region of the cross section, l i is the distance of the micro-element dA i to the neutral axis of the cross section, A i is the area of the i-th region of the cross section. If the robot bends in the horizontal direction, as shown in Figure 3 , formula (1) can be expressed as:

[0109] E m A1(y1-y)+E r A 21 (y 21 -y)-E r A 22 (y 22 -y)+E r A31 (y 31 -y)-E r A 32 (y 32 -y)=0 (2)

[0110] Where E m and E r These are the Young's moduli of the robot body and the polymer fiber rod, respectively; A1, A 21 A 22 A 31 and A 32 They are S1 and S 2-1 S 2-2 S 3-1 and S 3-2 The area; y1, y 21 y 22 y 31 and y 32 S1 and S 2-1 S 2-2 S 3-1 and S 3-2 The position of the neutral axis; y is the neutral axis of the cross section. Finally, y can be calculated from equation (2).

[0111]

[0112] Similarly, when the robot bends in the vertical direction, such as Figure 4 As shown, the neutral axis of the cross-section can be calculated as...

[0113]

[0114] Where A4 is the area of ​​S4; z 21 z 22 z 31 z 32 z4 and z4 are S 2-1 ,S 2-2 ,S 3-1 ,S 3-2 The neutral axis position of S4; z is the neutral axis of the cross section.

[0115] In equations (3) and (4), y 22 y 32 z 22 and z 32 It will change as the fiber rotates, as shown in the following formula.

[0116]

[0117] Where d eis the distance from the fiber eccentric inner lumen center to the fiber center, d is the distance between the fiber center and the robot center, q1 and q2 are the rotation angles of the two fibers, as shown in Figure 4 . In addition, the positive rotation direction of the two fibers is counterclockwise.

[0118] The bending moment and curvature of each unit body 1 in the horizontal and vertical directions of the two bendable sections can be represented as

[0119]

[0120] where M1 and M2 are the bending moments in the horizontal and vertical directions, κ y and κ z are the neutral axis curvatures in the horizontal and vertical directions, EI y and EI z are the bending stiffnesses in the horizontal and vertical directions, T1 and T2 are the tensions of the driving ropes in the two bendable sections, d c is the distance between the driving rope and the robot center axis.

[0121] To facilitate subsequent solving, three assumptions need to be noted. First, it is assumed that the length change of the driving rope corresponding to each unit body 1 is the same. Second, in the same unit body 1, it is assumed that the tension along the length direction of the driving rope is the same. Third, the effect of the rotation of the two fibers on the bending stiffness of the continuum robot is ignored. Since the materials and sizes of the two bendable sections in the same unit body 1 are the same, the bending stiffnesses in the horizontal and vertical directions can be considered to be equal, i.e., EI y = EI z . Therefore, equation (6) can be rewritten as

[0122]

[0123] When the driving rope is pulled, the angle of bending in each bending direction is

[0124]

[0125] where h is the length of each bendable section, θ y and θ z are the bending angles in the horizontal and vertical directions, dq 31 and dq 32 are the length changes of the driving rope in each unit body 1 due to horizontal bending and vertical bending, q3 / n = dq 31 + dq 32 , q3 is the total length change of the driving rope, and n is the total number of unit bodies 1. When q3 is known, θ y , θ z , κ y and κz which can be calculated according to equations (7) and (8).

[0126] The forward kinematics of each unit body 1 can be described as

[0127]

[0128]

[0129]

[0130] where P1 = [sin(θ y ),-(1-cos(θ y )),0] T / κ y , P2 = [h,0,0] T , P3 = [sin(θ z ),0,-(1-cos(θ z ))] T / κ z , and P4 = [h,0,0] T Finally, the forward kinematics of the robot can be expressed as

[0131]

[0132]

[0133] where is the second transformation matrix of the robot base to the first unit body 1, T s t e ip g is the second transformation matrix of the last unit body 1 of the robot to the robot end, and are the and translation vectors, respectively.

[0134] In equation (10), the inputs are q1, q2, and q3, and the output is the pose of the robot end. To explore the characteristics of the macro-micro motion of the robot, the effects of the stretching of the driving rope and the rotation of the two fibers on the robot motion are demonstrated by simulation.

[0135] First, the driving rope of the robot is stretched to different lengths, with a stretching length change interval of 0.1 mm, from 0 mm to 1.5 mm. When the driving rope reaches each position, the robot rotates one revolution around its own axis. The trajectory of the macro motion of the robot is shown in Figure 5 .

[0136] When q3 = 0, the rotation of the two fibers does not have any effect on the robot motion. Therefore, q3 is set to a certain value to let the robot bend at a certain angle. First, one of the fibers is rotated and the other fiber is kept stationary, the trajectory of the micro-motion is shown in Figure 6 (a). Second, q1 is rotated from 0° to 360° at an interval of 20°, and q2 rotates a full circle when q1 reaches each position, the trajectory of the micro-motion is shown in Figure 6 (b).

[0137] If only one fiber is rotated, the trajectory of the micro-motion is a closed curve. If both fibers are rotated, the trajectory of the micro-motion is a closed plane. This means that the robot has 2 degrees of freedom of micro-motion, which can move to any position in the closed plane. Assuming that the resolution of the driving motor of the driving rope and the resolution of the fiber rotation are 0.1° and 1°, respectively, and the motor rotation is converted to the flange diameter of the driving rope stretch of 10 mm, the micro-motion and macro-motion resolutions are 1.1 um and 270.5 um, respectively, when the bending angle of the robot is 51°. Compared with the macro-motion, the micro-motion has a significant advantage in the micron scale motion.

[0138] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be construed as limiting the present application.

[0139] The specific embodiments of the present application are described above. It should be understood that the present application is not limited to the specific embodiments described above, and various changes or modifications can be made by those skilled in the art within the scope of the claims, which does not affect the essential content of the present application. The embodiments of the present application and the features in the embodiments can be arbitrarily combined with each other without conflict.

Claims

1. A continuum robot macro-micro motion device based on eccentric mechanism, characterized in that, The application relates to a continuous body robot macro-micro motion device based on an eccentric mechanism. The rigid section of the unit body (1) is provided with a positioning block (2), the middle part of the positioning block (2) is formed with a central cavity (3), and eccentric macro drive cavities (4) and eccentric micro drive cavities (5) are further arranged on the positioning block (2); The macro drive cavities (4) are provided with driving ropes, and the micro drive cavities (5) are provided with bendable fibers with eccentric cavities; The two micro drive cavities (5) are arranged at an angle of 90 degrees with the central line of the central cavity (3) on the positioning block (2); The unit body (1) is a nickel-titanium tube with a symmetrical cutting groove structure, the unit body (1) comprises two rigid sections and two bendable sections, the two bendable sections are arranged between the two rigid sections, and the two bendable sections are oppositely arranged.

2. The continuum robot macro-micro motion device based on eccentric mechanism of claim 1, wherein, The rigid sections and the bendable sections are alternately connected, one rigid section has two adjacent bendable sections, one of the bendable sections is bent in the vertical direction, and the other bendable section is bent in the horizontal direction.

3. The continuum robot macro-micro motion device based on eccentric mechanism of claim 1, wherein, The positioning block (2) is in the shape of a circular sheet, and the positioning block (2) is coaxially arranged in the rigid section of the unit body (1).

4. The continuum robot macro-micro motion device based on eccentric mechanism of claim 1, wherein, The diameter of the bendable fiber with the eccentric cavity is sub-millimeter level.

5. A continuum robot macro-micro motion method based on eccentric mechanism, characterized in that, The application discloses a continuous body robot macro-micro motion device based on an eccentric mechanism. For a unit body (1), according to the material geometric deformation condition, the balance equation of the unit body (1) at the cross section can be obtained as follows: in, It is the cross-section of the first i Young's modulus of each region It is a microelement The distance to the neutral axis of the cross-section, It is the cross-section of the first i The area of ​​each region; If the robot is bent in the horizontal direction, it is expressed as: wherein, and are Young's moduli of the robot body and the polymer fiber rod, respectively; , , , and are areas of S1, S 2-1 , S 2-2 , S 3-1 and S 3-2 , respectively; , , , and are neutral axis positions of S1, S 2-1 , S 2-2 , S 3-1 and S 3-2 , respectively; y is a neutral axis of the cross section, and it can be derived that: ； When the robot is bent in the vertical direction, the neutral axis of the cross section is calculated as: wherein is the area of S4; z 21 , z 22 , z 31 , z 32 and z 4 are the neutral axis positions of S 2-1 , S 2-2 , S 3-1 , S 3-2 and S4, respectively; z is the neutral axis of the cross section; wherein , , and will change with rotation of the fiber as shown in the following equation: wherein is the distance of the fiber eccentric lumen center to the fiber center, d is the distance between the fiber center and the robot center, q 1 and q 2 are the rotation angles of the two fibers, in addition, the positive rotation direction of the two fibers is counterclockwise; The bending moment and the curvature of the two bendable parts of each unit body (1) in the horizontal and vertical directions are expressed as: wherein M 1 and M 2 are the bending moments in the horizontal and vertical directions, respectively, and are the neutral axis curvatures in the horizontal and vertical directions, respectively, and are the bending rigidities in the horizontal and vertical directions, respectively, T 1 and T 2 are the tensions of the driving ropes in the two bendable sections, respectively, is the distance between the driving ropes and the center axis of the robot.

6. The continuum robot macro-micro motion method based on eccentric mechanism of claim 5, wherein, In order to facilitate the solution, it is assumed that the length change of the driving rope corresponding to each unit body (1) is the same; in the same unit body (1), it is assumed that the tension along the length direction of the driving rope is the same; the influence of the rotation of the two fibers on the bending stiffness of the continuous body robot is ignored; Since the material and size of the two bendable parts in the same unit body (1) are the same, the bending stiffness in the horizontal and vertical directions is considered to be equal, i.e. ; ； When the driving rope is pulled, the angle of bending in each bending direction is: wherein, h L is the length of each bendable segment, and are the bending angles in horizontal and vertical directions, respectively, and are the changes in the length of the driving rope in each unit body (1) due to horizontal and vertical bending, respectively, , q 3 is the total change in the length of the driving rope, n is the total number of unit bodies (1); When q 3 is known, , , and can be calculated.

7. The continuum robot macro-micro motion method based on eccentric mechanism of claim 6, wherein, The forward kinematics of each unit body (1) can be described as: wherein , , , and .

8. The continuum robot macro-micro motion method based on eccentric mechanism of claim 7, wherein, The forward kinematics of the robot is expressed as: wherein, is the second transformation matrix of the robot base to the first unit (1), is the second transformation matrix of the last unit (1) of the robot to the robot end, and are respectively and translation vectors.

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