Continuous body instrument and surgical robot

Abstract

The invention provides a continuum instrument and a surgical robot. The continuum instrument comprises an inner-layer tube and an outer-layer tube, the outer-layer tube is arranged on the outer side of the inner-layer tube in a sleeving mode, the front end of the outer-layer tube and the front end of the inner-layer tube are fixed, and a first hollowed-out structure area is arranged on the outer-layer tube; from the front end of the outer-layer pipe to the rear end of the outer-layer pipe, the width of the first hollow structure area in the circumferential direction of the outer-layer pipe is gradually reduced. According to the continuum instrument, the defects that in the prior art, a continuum instrument is small in bending angle, prone to breakage after being used for many times, complex in structure and the like can be effectively overcome, and the effects of large-angle bending and reliable use for many times of the continuum instrument are achieved.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and in particular, to a continuum device and a surgical robot. Background Art

[0002] In the current technical field of continuum surgical instruments, in order to achieve precise intervention of instruments in complex body cavities, narrow spaces, and deep hidden parts of the human body, the prior art widely adopts a segmented flexible structure. This type of structure realizes the connection of each segment through hinges or similar joints. However, in practical applications, there are significant defects: firstly, the existence of joint gaps leads to discontinuous movement during the bending movement, making it difficult to meet the high-precision operation requirements in complex environments; secondly, limited by the deformation ability of the hinges or joints, the deflection angle range of the instrument is insufficient, and it is unable to adapt to the large-angle bending actions required for complex cavities, and may thus cause compression or damage to surrounding tissues during the operation.

[0003] In addition, some continuum devices adopt complex driving methods and rely on a large number of cables for control signal transmission and power transmission. Although this type of design can achieve a large angle of deflection, its stiffness controllability is poor in the state of large deformation, and due to the cable layout, the volume and weight of the instrument increase, further compressing the effective size of the tool channel, and significantly reducing the operation flexibility and practicality of the instrument in a narrow space. Summary of the Invention

[0004] The present application provides a continuum device to solve the defects in the prior art such as small bending angles of continuum devices, easy fracture after multiple uses, and complex structures, and to achieve the effects of large-angle bending and reliable multiple uses of the connection body device.

[0005] The present application also proposes a surgical robot.

[0006] A continuum device according to an embodiment of the first aspect of the present application, the continuum device includes: an inner layer tube and an outer layer tube, the outer layer tube is sleeved outside the inner layer tube, the front ends of the outer layer tube and the inner layer tube are fixed, and a first hollowed-out structure area is provided on the outer layer tube; From the front end to the rear end of the outer layer tube, the width of the first hollowed-out structure area in the circumferential direction of the outer layer tube gradually decreases.

[0007] According to an embodiment of the present application, the included angle between the boundary line of the first hollowed-out structure area in the axial direction of the outer layer tube and the generatrix of the outer layer tube is 0.1° to 5°.

[0008] According to an embodiment of the present application, the first hollowed-out structure area is formed on the wall surface of the outer layer tube by projecting a plane trapezoid.

[0009] According to one embodiment of the present application, the plane trapezoid is an isosceles trapezoid or a right-angled trapezoid.

[0010] According to one embodiment of the present application, with a generatrix of the outer tube as the axis of symmetry, the first hollow structure area is axisymmetric.

[0011] According to one embodiment of the present application, a plurality of hollow holes are provided on the outer tube, and the plurality of hollow holes are arranged in an array along the circumferential direction and the axial direction of the outer tube to form the first hollow structure area.

[0012] According to one embodiment of the present application, the hollow hole is a zigzag hole; A plug connector and a plug slot are formed on the outer tube. The plug connector is located in the plug slot, and the gap between the plug connector and the slot wall of the plug slot forms the hollow hole.

[0013] According to one embodiment of the present application, the width of the end portion of the plug connector is greater than the opening width of the plug slot.

[0014] According to one embodiment of the present application, when the front end of the outer tube is bent to a maximum angle toward the side where the first hollow structure area is provided, the end of the plug connector along the axial direction of the outer tube abuts against the bottom of the plug slot to limit the front end of the outer tube from further bending; When the front end of the outer tube is bent to a maximum angle facing away from the first hollow structure area, the plug connector abuts against both sides of the plug slot along both sides of the circumference of the outer tube to limit further bending of the front end of the outer tube.

[0015] According to one embodiment of the present application, the hollow hole is a triangular hole, a quadrilateral hole or a long hole.

[0016] According to one embodiment of the present application, the rear end of the inner tube is configured to be connected to a driving mechanism, and the inner tube drives the outer tube to bend or straighten.

[0017] According to one embodiment of the present application, a second hollow structure area corresponding to the first hollow structure area is provided on the inner tube.

[0018] According to one embodiment of the present application, the first hollow structure area and the second hollow structure area are arranged opposite to each other in the radial direction of the inner tube.

[0019] According to one embodiment of the present application, the inner tube and the outer tube are concentrically arranged.

[0020] According to one embodiment of the present application, the material of the inner tube is stainless steel, titanium alloy or nickel-titanium alloy, and / or the material of the outer tube is stainless steel, titanium alloy or nickel-titanium alloy.

[0021] A surgical robot according to an embodiment of the second aspect of the present application, the surgical robot includes a driving mechanism, a robot body, and the aforementioned continuum instrument, and the driving mechanism is arranged on the robot body; The rear end of the inner layer tube is connected to the driving mechanism, and the rear end of the outer layer tube is fixed on the robot body.

[0022] One or more of the above technical solutions in the embodiments of the present application have at least one of the following technical effects: A first hollowed-out structure area is arranged on the continuum instrument composed of the inner layer tube and the outer layer tube, so that the continuum instrument has a certain bending ability. At the same time, by adjusting the size of the first hollowed-out structure area, the width of the first hollowed-out structure area on the outer layer tube gradually changes. The width of the first hollowed-out structure area is reduced at the rear end position of the outer layer tube where it is prone to breakage, thereby reducing the influence of the first hollowed-out structure area on the stiffness of the rear end position of the outer layer tube. The width of the first hollowed-out structure area is increased at the front end position of the outer layer tube where it is not prone to breakage, improving the bending ability of the front end of the outer layer tube. The above structure improves the stiffness of the most easily broken part of the outer layer tube, effectively improves the overall service life of the continuum instrument. And the above structure has high reliability, does not greatly increase the structural complexity of the continuum instrument, and will not cause the situation of increased weight or inconvenient bending of the continuum instrument.

[0023] The additional aspects and advantages of the present application will be partially given in the following description, partially will become obvious from the following description, or will be understood through the practice of the present application. Description of the Drawings

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following will briefly introduce the drawings required for use in the description of the embodiments or related technologies. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0025] Figure 1 is a structural schematic diagram of the continuum instrument provided by the present application Figure 1 (the continuum instrument is in a straight state).

[0026] Figure 2 is Figure 1 a structural schematic diagram of the first hollowed-out structure area in (the middle part of the hollowed-out holes is omitted).

[0027] Figure 3 is Figure 2 a structural schematic diagram of the hollowed-out hole in (the zigzag hole).

[0028] Figure 4Schematic diagram of the second first hollow structure region provided by this application (the hollow hole is a zigzag hole and is flipped relative to Figure 2 ).

[0029] Figure 5 is Figure 4 the schematic diagram of the structure of the hollow hole in

[0030] Figure 6 Schematic diagram of the third first hollow structure region provided by this application (the hollow hole is a rectangular hole).

[0031] Figure 7 is the schematic diagram of the continuum device provided by this application Figure 2 (the hollow hole is a rectangular hole; the continuum device is in a straight state).

[0032] Figure 8 is the schematic diagram of the continuum device provided by this application Figure 3 (the hollow hole is a rectangular hole; the front end of the continuum device is bent towards one side).

[0033] Figure 9 is the schematic diagram of the continuum device provided by this application Figure 4 (the hollow hole is a rectangular hole; the front end of the continuum device is bent towards the other side).

[0034] Figure 10 Schematic diagram of the fourth first hollow structure region provided by this application (the hollow hole is a rhombus hole).

[0035] Figure 11 Schematic diagram of the fourth first hollow structure region provided by this application (the hollow hole is a long strip hole).

[0036] Reference numerals: 1. Outer tube; 2. Inner tube; 3. First hollow structure region; 31. Hollow hole; 311. Plug connector; 312. Plug socket; 313. Opposite sides; 314. Hypotenuse; 4. Unhollowed solid part. Detailed implementation manners

[0037] The following further describes in detail the implementation manners of this application with reference to the drawings and embodiments. The following embodiments are used to illustrate this application, but cannot be used to limit the scope of this application.

[0038] In the description of the embodiments of the present application, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0039] In the description of the embodiments of this application, it should be noted that, unless otherwise specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of this application based on the specific circumstances.

[0040] In the embodiments of the present application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, a first feature being "above," "above," and "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0041] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0042] According to a first aspect of the present application, a continuum device is Figures 1 to 11As shown in the figure, the continuum device includes an inner layer tube 2 and an outer layer tube 1. The outer layer tube 1 is sleeved outside the inner layer tube 2. The front ends of the outer layer tube 1 and the inner layer tube 2 are fixed. A first hollow structure area 3 is provided on the outer layer tube 1. From the front end to the rear end of the outer layer tube 1, the width of the first hollow structure area 3 gradually decreases in the circumferential direction of the outer layer tube 1.

[0043] The continuum device is composed of an inner tube and an outer layer tube 1. The outer layer tube 1 is sleeved outside the inner layer tube 2. The front ends of the outer layer tube 1 and the inner layer tube 2 are fixed by welding to maintain synchronous movement. The outer layer tube 1 and the inner layer tube 2 are bent and deformed together. In Figure 1 the left side in the figure is the front end of the outer layer tube 1 (i.e., the front end of the continuum device), Figure 1 and the right side in the figure is the rear end of the outer layer tube 1 (i.e., the rear end of the continuum device).

[0044] A first hollow structure area 3 is provided on the outer layer tube 1 to enable the outer layer tube 1 to have better bending ability. Since the outer layer tube 1 has certain stiffness requirements, the outer layer tube 1 is not provided with a hollow structure in the entire circumferential 360°.

[0045] Through multiple experiments and analyses, it is known that setting a hollow area on the outer layer tube can improve the bending ability of the outer layer tube, but it will reduce the stiffness of the outer layer tube to a certain extent. Especially when the continuum device is a cantilever structure, the position where the hollow area is close to the rear end of the outer layer tube (i.e., the bending root) is prone to stress concentration and cause fatigue fracture; the stiffness in the large-angle bending state is not high, and it is prone to secondary deformation under the action of external forces. In this application, the circumferential direction of the outer layer tube 1 includes a first hollow structure area 3 and an unhollowed solid part 4. The layout of the first hollow structure area 3 in this application is optimized, so that the width of the first hollow structure area 3 gradually decreases from the front end to the rear end of the outer layer tube 1. A hollow structure area with a smaller width is set at the easily fractured position at the rear end of the outer layer tube 1, the circumferential length of the unhollowed solid part 4 is increased, the stiffness at the easily fractured position at the rear end of the outer layer tube 1 is increased, so that the entire outer layer tube 1 realizes "equal strength" at each position in the axial length, thereby improving the service life of the continuum device, and having the performance of a larger bending angle, higher stiffness, and stronger anti-fatigue performance under the same outer diameter.

[0046] Of course, the first hollow structure area 3 is not provided throughout the entire axial length of the outer layer tube 1. In other words, the length of the first hollow structure area 3 is less than the length of the outer layer tube 1, as shown in Figure 1 、 Figure 7 、 Figure 8 、 Figure 9 the figure.

[0047] It should be noted that the first hollow structure region 3 is not a single integral hollow area, but a hollow structure region formed by combining multiple smaller hollow areas. In other words, there are both hollow holes 31 and non-hollowed solid parts in the first hollow structure region 3, such as Figure 1 , Figure 7 , Figure 8 , Figure 9 shown. The non-hollowed solid parts retain a certain bending and stretching stiffness, providing basic structural support and shape retention ability for the continuum device.

[0048] According to an embodiment of the present application, the included angle a between the boundary line of the first hollow structure region 3 in the axial direction of the outer tube 1 and the generatrix of the outer tube 1 is 0.1° to 5°, as Figure 2 and Figure 4 shown. It should be noted that Figure 6 , Figure 10 and Figure 11 also have the included angle of this angle set therein.

[0049] By adjusting the range of the above-mentioned included angle, the optimal effect of the continuum device can be achieved according to different requirements, specific hollow structures, etc.

[0050] According to an embodiment of the present application, as Figure 2 , Figure 4 , Figure 6 , Figure 10 and Figure 11 shown, the first hollow structure region 3 is formed on the wall surface of the outer tube 1 by projecting a plane trapezoid.

[0051] The first hollow structure region 3 can be processed by laser cutting. Setting the first hollow structure region 3 as formed by projecting a plane trapezoid can facilitate the laser cutting.

[0052] Among them, the projection method can be orthographic projection.

[0053] According to an embodiment of the present application, the plane trapezoid is an isosceles trapezoid or a right trapezoid.

[0054] The form of the isosceles trapezoid is easy to set, and due to its symmetry, when the outer tube 1 bends towards the side where the first hollow structure region 3 is provided and the side opposite to the first hollow structure region 3, its bending angle can be better controlled.

[0055] Of course, in some cases, the plane trapezoid can also be an ordinary regular trapezoid or a right trapezoid.

[0056] According to an embodiment of the present application, with a generatrix of the outer tube 1 as the axis of symmetry, the first hollow structure region 3 is axisymmetric.

[0057] In addition to the aforementioned trapezoid, the first hollow structure region 3 can also be formed by projecting other axisymmetric figures. For example, replace the two waists of an isosceles trapezoid with symmetric curves.

[0058] According to an embodiment of the present application, as Figure 2 , Figure 4 , Figure 6 , Figure 10 and Figure 11 shown, a plurality of hollow holes 31 are provided on the outer layer tube 1, and the plurality of hollow holes 31 are arranged in an array along the circumferential direction and the axial direction of the outer layer tube 1 to form the first hollow structure region 3.

[0059] The hollow holes 31 are generated by 2D plane design, and after being projected onto the outer surface of the outer layer tube 1, they form a 3D shape, and then the processing of the cutting pattern is realized through a round tube cutting technology (such as laser cutting). The aforementioned "the first hollow structure region 3 can be processed by laser cutting" means that the hollow holes 31 in the first hollow structure region 3 are processed by laser cutting.

[0060] A plurality of hollow holes 31 are arranged in an array on the outer layer tube 1 to form the first hollow structure region 3. The first hollow structure region 3 includes both the hollow holes 31 and the solid parts that are not hollowed out.

[0061] According to an embodiment of the present application, as Figures 1 to 5 shown, the hollow hole 31 is a broken line-shaped hole; an insertion joint 311 and an insertion slot 312 are formed on the outer layer tube 1, the insertion joint 311 is located in the insertion slot 312, and the gap between the insertion joint 311 and the slot wall of the insertion slot 312 forms the hollow hole 31.

[0062] The broken line-shaped hollow hole 31 can enable the outer layer tube 1 to have stronger bending deformation ability.

[0063] The lengths of the sides of the broken line-shaped hole, the slit width (which can also be called the opening width of the hollow hole 31), the included angle b of the hypotenuse of the broken line-shaped hole, as well as the number and spacing of the axial arrangement of the broken line-shaped holes, the number and spacing of the circumferential arrangement of the broken line-shaped holes, etc., can all be adjusted according to the actual situation.

[0064] The broken line-shaped hole is also convenient for adjusting the maximum deflection angle of the continuum device: When the total length of the first hollow structure region 3 remains unchanged, when it is necessary to reduce the maximum deflection angle of the continuum device, it can be achieved by reducing the cutting slit width, reducing the included angle b of the hypotenuse, reducing the number of axial arrays, increasing the array spacing between adjacent hollow holes 31, etc.; when it is necessary to increase the maximum deflection angle, it can be achieved by increasing the cutting slit width, increasing the included angle b of the hypotenuse, increasing the number of arrays, reducing the array spacing between adjacent hollow holes 31, etc.

[0065] The hollow hole 31 can also be in the shape of "Ω".

[0066] According to an embodiment of the present application, as Figures 2 to 5 shown, the width of the end of the plug connector 311 is greater than the opening width of the plug slot 312.

[0067] The width of the end of the plug connector 311 in the circumferential direction of the outer tube 1 is greater than the width of the opening of the plug slot 312. During the bending deformation process of the outer tube 1, it is possible to prevent the plug connector 311 from disengaging from the plug slot 312, thereby limiting the maximum bending angle of the outer tube 1 and avoiding direct damage to the outer tube 1 due to excessive bending.

[0068] By adjusting the seam width, the limit value of the maximum deformation angle of the outer tube 1 (i.e., the maximum deflection angle of the continuum device) can be changed. The distance between the end of the plug connector 311 and the bottom of the plug slot 312 also belongs to a type of seam width.

[0069] According to an embodiment of the present application, when the front end of the outer tube 1 bends towards the side where the first hollow structure area 3 is provided to the maximum angle, the end of the plug connector 311 in the axial direction of the outer tube 1 abuts against the bottom of the plug slot 312 to limit the further bending of the front end of the outer tube 1; when the front end of the outer tube 1 bends away from the side where the first hollow structure area 3 is provided to the maximum angle, both sides of the plug connector 311 in the circumferential direction of the outer tube 1 abut against both sides of the plug slot 312 to limit the further bending of the front end of the outer tube 1. It should be noted that during the bending process of the outer tube 1, the inner tube 2 rotates synchronously with the outer tube 1.

[0070] When both sides of the plug connector 311 in the circumferential direction of the outer tube 1 abut against both sides of the plug slot 312, it can effectively limit the further bending of the front end of the outer tube 1 when it bends away from the side where the first hollow structure area 3 is provided to the maximum angle, and avoid direct damage to the outer tube 1 due to excessive bending. When the end of the plug connector 311 in the axial direction of the outer tube 1 abuts against the bottom of the plug slot 312, it can effectively limit the further bending of the front end of the outer tube 1 when it bends towards the side where the first hollow structure area 3 is provided to the maximum angle, and avoid direct damage to the outer tube 1 due to excessive bending.

[0071] According to an embodiment of the present application, the hollow hole 31 is a triangular hole (not shown in the figure), a quadrilateral hole (such as Figure 6 and Figure 10 shown) or a long strip hole (such as Figure 11 shown).

[0072] Except for the case where the aforementioned hollow hole 31 is a broken line-shaped hole, the hollow hole 31 can also adopt forms such as a triangular hole, a quadrilateral hole or a long strip hole.

[0073] It should be understood that the specific shape of the hollow hole 31 can be further adjusted according to actual needs. For example, the hollow hole 31 can also be a circular hole, an oval hole, a polygonal hole, etc.

[0074] According to an embodiment of the present application, the rear end of the inner layer tube 2 is arranged to be connected to the driving mechanism, and the inner layer tube 2 drives the outer layer tube 1 to bend or straighten.

[0075] The driving mechanism applies forces in two directions of pushing or pulling to the inner layer tube 2, so that the inner layer tube 2 and the outer layer tube 1 are bent and deformed together. The front ends of the inner layer tube 2 and the outer layer tube 1 are connected by welding; the rear end of the inner layer tube 2 is connected to the driving mechanism as the driving end, and the rear end of the outer layer tube 1 is fixed to the instrument body (such as a robot body) as the fixed end to form a cantilever structure.

[0076] According to an embodiment of the present application, a second hollow structure area corresponding to the first hollow structure area 3 is provided on the inner layer tube 2 (not shown in the figure).

[0077] The shape of the second hollow structure area, the shape of the hollow holes in the second hollow structure area, the number of hollow holes, the arrangement method of the hollow holes, etc. can all be set with reference to the first hollow structure area 3. The diameter of the inner layer tube 2 where the second hollow structure area is located is smaller than that of the outer layer tube 1 where the first hollow structure area 3 is located. Therefore, the size of the second hollow structure area, the size of the hollow holes, etc. can be correspondingly reduced. The specific values can be adjusted according to the actual situation and will not be elaborated here.

[0078] According to an embodiment of the present application, the first hollow structure area 3 and the second hollow structure area are arranged opposite to each other in the radial direction of the inner layer tube 2 (not shown in the figure).

[0079] By arranging the first hollow structure area 3 and the second hollow structure area opposite to each other, it is avoided that the continuum instrument is too easy to bend towards one side, while the resistance when bending towards the other side is too large.

[0080] According to an embodiment of the present application, the inner layer tube 2 and the outer layer tube 1 are concentrically arranged.

[0081] The inner diameter of the outer layer tube 1 can be slightly larger than the outer diameter of the inner layer tube 2. For example, the difference can be 0.1 mm.

[0082] According to an embodiment of the present application, the material of the inner layer tube 2 is stainless steel, titanium alloy or nickel-titanium alloy, and / or the material of the outer layer tube 1 is stainless steel, titanium alloy or nickel-titanium alloy. Specifically, it can be 316L stainless steel.

[0083] Of course, other metals with good biocompatibility and high toughness can also be selected for the inner layer tube 2 and the outer layer tube 1.

[0084] The continuum instrument in the present application can not only be used alone, but also be developed into other forms of flexible continuum instruments through forms such as parallel connection or series connection to complete more complex multi-dimensional bending deformation and be applicable to more complex scenarios.

[0085] The following examples illustrate the specific dimensions that the outer tube 1 and the inner tube 2 can adopt: The diameters of the inner tube 2 and the outer tube 1 can be: 1 to 15 mm, the wall thicknesses of the inner tube 2 and the outer tube 1 can be: 0.05 to 1 mm, the lengths of the inner tube 2 and the outer tube 1 can be: 100 to 1000 mm, the circumferential arrangement quantity of the hollow holes 31 can be: 1 to 10, the axial arrangement quantity of the hollow holes 31 can be: 50 to 500, the axial spacing between two adjacent hollow holes 31 can be: 0.1 to 1 mm, and the slit width of the hollow holes 31 can be: 0.01 to 0.05 mm. When the hollow hole 31 is a zigzag hole, the spacing d between the opposite sides 313 in the axial direction can be: 0.1 to 0.5 mm, and the mortise and tenon oblique angle c can be: 20 to 70°.

[0086] Specifically, the metal tubes of the inner tube 2 and the outer tube 1 are made of 316L stainless steel tubes, with the outer diameter size, wall thickness and length being Ф2.0×0.1×200 mm and Ф1.7×0.1×200 mm respectively. Through the laser processing technology, the inner tube 2 and the outer tube 1 are processed into a skeleton structure with specific shapes and dimensions according to a specific cutting pattern. The cutting pattern adopts the mortise and tenon shape (that is, the hollow hole 31 adopts the form of a zigzag hole). The circumferential and axial uniform arrangement quantities of the outer tube 1 are 4 and 104 respectively, the axial spacing is 0.3 mm, the slit width of the hollow hole 31 is 0.03 mm, the spacing d between the opposite sides 313 in the axial direction is 0.13 mm, and the mortise and tenon oblique angle c is 30°; the circumferential and axial uniform arrangement quantities of the inner tube 2 are 4 and 82 respectively, the axial spacing is 0.22 mm, the slit width of the hollow hole 31 is 0.03 mm, the spacing between the opposite sides 313 in the axial direction is 0.12 mm, and the mortise and tenon oblique angle is 30°. It should be noted that Figures 7 to 9 the rear end of the inner tube 2 shown in extends beyond the rear end of the outer tube 1, which is only to illustrate that "the inner tube 2 is arranged in the outer tube 1", and it is not necessarily that the length of the inner tube 2 is greater than the length of the outer tube 1. As described above, the lengths of the inner tube 2 and the outer tube 1 can both be set to 200 mm.

[0087] The inner tube 2 and the outer tube 1 generate bidirectional bending deformation through bidirectional relative translation. When the inner tube 2 (the driving tube) moves, the front end of the inner tube 2 drives the outer tube 1 to move synchronously. Since the rear end of the outer tube 1 is fixed to the instrument body (such as a robot body), in order to coordinate the axial deformation of the inner tube 2, the inner tube 2 and the outer tube 1 will, under the guidance of the cutting pattern (i.e., the first hollow structure area 3 or the second hollow structure area), convert the axial driving deformation of the inner tube 2 into the planar bending deformation of the two tubes of the inner tube 2 and the outer tube 1. Axial pushing or pulling in two directions can be applied to the inner tube 2, corresponding to the upper or lower deflection directions of the front end of the concentric tube in the bending plane. The continuum instrument is a 3-degree-of-freedom system. In addition to generating the degree of freedom of planar bending deformation through the axial driving deformation of the inner tube 2, the outer tube 1 and the inner tube 2 can apply the degrees of freedom of overall rigid translation and circumferential rotation.

[0088] In this application, a first hollow structure area 3 is provided on the continuum instrument composed of the inner tube 2 and the outer tube 1, so that the continuum instrument has a certain bending ability. At the same time, by adjusting the size of the first hollow structure area 3, the width of the first hollow structure area 3 on the outer tube 1 gradually changes. The width of the first hollow structure area 3 is reduced at the rear end position of the outer tube 1 where it is prone to breakage, thereby reducing the influence of the first hollow structure area 3 on the stiffness of the rear end position of the outer tube 1. The width of the first hollow structure area 3 is increased at the front end position of the outer tube 1 where it is not prone to breakage, improving the bending ability of the front end of the outer tube 1. The above structure improves the stiffness of the most easily broken part of the outer tube 1, effectively improving the overall fatigue life of the continuum instrument. And the above structure has high reliability, does not greatly increase the structural complexity of the continuum instrument, and will not cause the situation of increased weight or inconvenient bending of the continuum instrument.

[0089] The structure of the equal-strength concentric tube continuum instrument in this application, based on the equal-strength design method, makes the strength of each part adapt to the load it bears, so that the materials of each part of the entire structure can fully exert their bearing capacity during the working process, in order to achieve the best material utilization effect and structural performance.

[0090] After testing, the maximum deflection angle of the equal-strength continuum instrument in this application can reach 166°, exceeding the maximum deflection angle (157°) in the case of traditional equal-cross-section design. The bending stiffness of the equal-strength continuum instrument in this application in the deflection plane can reach 10 N•mm 2 , greatly exceeding the bending stiffness of the traditional design (7.6 N•mm 2 ). During the bending process of the continuum instrument, the bending deformation of the existing design scheme is mainly concentrated at the rear end, while the bending deformation of the equal-strength continuum instrument in this application moves forward, weakening the stress concentration at the root; the maximum stress values at the root of the existing design scheme and this application are approximately 226 MPa and 198 MPa respectively, and the stress reduction is about 12.4%.

[0091] Through the design of the hollow structure on the walls of the concentric tubes (i.e., the outer tube 1 and the inner tube 2), the continuum device is enabled to have large-angle bending, high bending stiffness, and strong fatigue resistance. The hollow structure adopts a parametric method. By optimizing and adjusting the size parameters and array parameters of a single hollow hole 31, structural schemes with different maximum bending angles and different axial distributions of bending stiffness can be designed according to needs, greatly improving the axial stress distribution of the concentric tube structure, thereby facilitating the improvement of the fatigue resistance of the structure. The continuum device in this application is applicable to fields such as medical catheters and industrial detection, and has advantages such as high degrees of freedom, high precision, low cost, and flexibility, meeting the requirements of complex path navigation and operation in narrow spaces.

[0092] The equal-strength design of the hollow structure of the concentric tubes enables the device to have the ability of large-angle bending. Under the action of opposing forces on the inner tube 2 and the outer tube 1, the hollow structure can produce a large range of elastic deformation. By elastically increasing and decreasing the reserved slit width, a larger bending angle can be generated under the same outer diameter of the concentric tubes. This is beneficial for adapting to deformation and movement in complex cavities and narrow space environments, increasing the operation flexibility. The bending stiffness of the structure is achieved by the planar contact of the cutting surfaces of the hollow structure. Under the equal-strength design, the hollow cross-sections in each axial direction can reach the contact state simultaneously, rather than some cross-sections reaching the contact state while some cross-sections have not reached the contact state, thereby being able to further improve the bending load-bearing capacity of the structure and achieve the purpose of increasing the bending stiffness. The structural fatigue fracture of the concentric tubes mainly occurs at the stress concentration points. In traditional designs, stress concentration is prone to occur at the bending root. Each time there is a bending deformation, this location needs to undergo an alternating load with a high stress value, so fatigue fracture is extremely likely to occur here, causing structural failure. However, the equal-strength design averages and reduces the bending stress of the entire concentric tube axially, with the stress levels being the same everywhere, so stress concentration does not occur locally, greatly reducing the peak value of the alternating stress during bending operations, thereby improving the fatigue resistance of the concentric tube structure.

[0093] A surgical robot according to an embodiment of the second aspect of the present application, the surgical robot includes a driving mechanism, a robot body, and the aforementioned continuum device, and the driving mechanism is arranged on the robot body; the rear end of the inner tube 2 is connected to the driving mechanism, and the rear end of the outer tube 1 is fixed on the robot body.

[0094] The driving mechanism can be manual, electric, or hydraulic.

[0095] Finally, it should be noted that the above embodiments are only used to illustrate the present application, rather than limiting the present application. Although the present application has been described in detail with reference to the embodiments, those of ordinary skill in the art should understand that various combinations, modifications or equivalent replacements of the technical solutions of the present application do not depart from the spirit and scope of the technical solutions of the present application, and should all be covered within the scope of the claims of the present application.

Claims

1. A continuum device, characterized in that, Comprising: An inner tube (2) and an outer tube (1), the outer tube (1) is sleeved outside the inner tube (2), the front ends of the outer tube (1) and the inner tube (2) are fixed, and a first hollow structure area (3) is provided on the outer tube (1); From the front end of the outer tube (1) to the rear end of the outer tube (1), the width of the first hollow structure area (3) in the circumferential direction of the outer tube (1) gradually decreases.

2. The continuum device according to claim 1, wherein The included angle between the boundary line of the first hollow structure area (3) in the axial direction of the outer tube (1) and the generatrix of the outer tube (1) is 0.1° to 5°.

3. The continuum device according to claim 1, wherein The first hollow structure area (3) is formed on the wall surface of the outer tube (1) by projection from a plane trapezoid.

4. The continuum device according to claim 3, wherein The plane trapezoid is an isosceles trapezoid or a right trapezoid.

5. The continuum device according to claim 1, wherein Taking a generatrix of the outer tube (1) as the axis of symmetry, the first hollow structure area (3) is axisymmetric.

6. The continuum device according to claim 1, wherein A plurality of hollow holes (31) are provided on the outer tube (1), and the plurality of hollow holes (31) are arranged in an array in the circumferential direction and the axial direction of the outer tube (1) to form the first hollow structure area (3).

7. The continuum device according to claim 6, wherein The hollow hole (31) is a polygonal hole; A plug joint (311) and a plug slot (312) are formed on the outer tube (1), the plug joint (311) is located in the plug slot (312), and the gap between the plug joint (311) and the slot wall of the plug slot (312) forms the hollow hole (31).

8. The continuum device according to claim 7, wherein, The width of the end of the plug joint (311) is greater than the opening width of the plug slot (312).

9. The continuum device according to claim 8, wherein When the front end of the outer tube (1) bends towards the side where the first hollow structure area (3) is provided to the maximum angle, the end of the plug joint (311) in the axial direction of the outer tube (1) abuts against the bottom of the plug slot (312) to limit the continuous bending of the front end of the outer tube (1); When the front end of the outer tube (1) bends away from the side where the first hollow structure area (3) is provided to the maximum angle, the two sides of the plug joint (311) in the circumferential direction of the outer tube (1) abut against the two sides of the plug slot (312) to limit the continuous bending of the front end of the outer tube (1).

10. The continuum device according to claim 6, wherein The hollow hole (31) is a triangular hole, a quadrilateral hole or a long strip hole.

11. The continuum device according to any one of claims 1 to 10, characterized in that, The rear end of the inner tube (2) is arranged to be connected to a driving mechanism, and the inner tube (2) drives the outer tube (1) to bend or straighten.

12. The continuum device according to any one of claims 1 to 10, characterized in that, A second hollow structure area corresponding to the first hollow structure area (3) is provided on the inner tube (2).

13. The continuum device according to claim 12, wherein The first hollow structure area (3) and the second hollow structure area are oppositely arranged in the radial direction of the inner tube (2).

14. The continuum device according to any one of claims 1 to 10, characterized in that, The inner tube (2) and the outer tube (1) are concentrically arranged.

15. The continuum device according to any one of claims 1 to 10, characterized in that, The material of the inner tube (2) is stainless steel, titanium alloy or nickel-titanium alloy, and / or the material of the outer tube (1) is stainless steel, titanium alloy or nickel-titanium alloy.

16. A surgical robot, characterized in that, Comprising a driving mechanism, a robot body and a continuum instrument according to any one of claims 1 to 15, the driving mechanism is arranged on the robot body; The rear end of the inner tube (2) is connected to the driving mechanism, and the rear end of the outer tube (1) is fixed to the robot body.

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