Curved body manipulators and curved body robots

Abstract

To suppress bending of a linear member between a connection member and a curving body.SOLUTION: A curving body manipulator has: a curving body that includes a curving section; a guide member; and a plurality of input parts connected to the curving section. Each among the plurality of input parts has: (i) a linear member that is connected to the curving section, extends along an extension direction, and is configured so as to cause the curving section to curve when movement occurs along the extension direction; (ii) and a connecting member that has a force receiving part and a fixed part to which the linear member is fixed, is capable of moving along a movement direction, with the force receiving part disposed at a position further from the linear member than the fixed part in a direction orthogonal to the extension direction. When the force receiving part receives a force, the connecting member moves along the movement direction as a result of being guided by the guide member such that the linear member moves along the extension direction. The fixed part is disposed such that the linear member extends in a straight line between the curving body and the fixed part.SELECTED DRAWING: Figure 3

Description

Technical Field

[0005] , , ,

[0001] The present invention relates to a curved body manipulator having a curved portion curved by a linear member, and a curved body robot having the curved manipulator.

Background Art

[0002] In fields such as medical endoscopes and industrial endoscopes, there is a curved body manipulator that is elongated, with a curved portion provided near the tip, and the curvature of the curved portion can be manipulated by pushing and pulling a linear member such as a wire.

[0003] Patent Document 1 discloses a configuration in which a curved body is curved by a wire. Specifically, one end of the wire is connected to the curved body, and the other end is connected to a drive rod. Then, a force is applied to the drive rod, and the drive rod moves the wire, thereby curving the curved body. The drive rod is disposed at a position offset from the center of the curved body, and the wire is bent between the curved body and the drive rod along the groove of the cylindrical body and is connected to the drive rod.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In a configuration where a connecting member, which is connected to a linear member, receives a force that causes the linear member to move and the curved portion to curve, if the linear member is bent between the connecting member and the curved body, the bending of the linear member may affect the bending operation of the curved portion caused by the movement of the connecting member. For example, the trajectory of the linear member and the frictional force generated between the linear member and the member guiding the linear member will differ depending on whether the linear member is being pushed or pulled. As a result, the relationship between the movement of the connecting member and the movement of the curved portion may differ depending on whether the linear member is being pushed or pulled.

[0006] One of the objectives of the present invention is to suppress the bending of the linear member between the connecting member and the curved body. [Means for solving the problem]

[0007] One of the inventions related to this application is as follows:

[0008] A curved body including a curved section, Guide member and A plurality of input units connected to the curved portion, each having (i) a linear member connected to the curved portion, extending along the extension direction, and configured to curve the curved portion when moved along the extension direction, and (ii) a connecting member having a fixing portion to which the linear member is fixed and a force receiving portion, and being movable along the direction of movement, wherein the force receiving portion is positioned further from the linear member than the fixing portion in a direction perpendicular to the extension direction, It has, When the force receiving portion receives force, the connecting member is guided by the guide member and moves along the direction of movement so that the linear member moves along the extension direction. The fixing portion is positioned such that the linear member extends in a straight line between the curved body and the fixing portion. 、 The guide member has a groove into which the connecting member fits. A curved body manipulator characterized by [this feature].

[0009] One of the inventions related to this application is as follows:

[0010] A curved body including a curved portion and having multiple holes, Guide member and A plurality of input units connected to the curved portion, each having (i) a linear member connected to the curved portion, extending along the extension direction, and configured to curve the curved portion when moved along the extension direction, and (ii) a connecting member having a fixing portion to which the linear member is fixed and a force receiving portion, and being movable along the direction of movement, wherein the force receiving portion is positioned further from the linear member than the fixing portion in a direction perpendicular to the extension direction, It has, The linear member has a portion that is inserted into one of the plurality of holes and fixed to the fixing portion, When the force receiving portion receives force, the connecting member is guided by the guide member and moves along the direction of movement so that the linear member moves along the extension direction. A curved body manipulator characterized in that, when viewed along the aforementioned direction of movement, the fixed portion and one of the plurality of holes at least partially overlap. [Effects of the Invention]

[0011] The present invention can suppress the bending of the linear member between the connecting member and the curved body. [Brief explanation of the drawing]

[0012] [Figure 1] (a) and (b) are perspective views of the curved manipulator according to Example 1. [Figure 2] (a) Front view of the curved manipulator according to Embodiment 1, (b) Rear view of the curved manipulator according to Embodiment 1. [Figure 3] (a) A schematic cross-sectional view of the curved manipulator according to Example 1, (b) and (c) Enlarged views of the curved manipulator according to Example 1. [Figure 4](a) Schematic front view of the central member according to Example 1, (b) Schematic cross-sectional view of the central member according to Example 1, (c) Schematic rear view of the central member according to Example 1. [Figure 5] (a) Schematic front view of the tip member and the guide ring according to Example 1, (b) Schematic side view of the tip member and the guide ring according to Example 1. [Figure 6] (a) Schematic front view of the tubular member according to Example 1, (b) Schematic side view of the tubular member according to Example 1. [Figure 7] (a) Schematic front view of the connecting member according to Example 1, (b) Schematic side view of the connecting member according to Example 1. [Figure 8] (a) Schematic front view of the state where the linear member according to Example 1 is joined to the connecting member, (b) Schematic side view of the state where the linear member according to Example 1 is joined to the connecting member, (c), (d) Enlarged views of the state where the linear member according to Example 1 is joined to the connecting member. [Figure 9] Schematic perspective view of the curved body manipulator in the state where the curved portion according to Example 1 is bent. [Figure 10] Schematic cross-sectional view of the curved body manipulator in the state where the curved portion according to Example 1 is bent. [Figure 11] (a)(b)(c) Schematic perspective views of the curved body manipulator according to Example 2, (d) Enlarged view of the curved body manipulator. [Figure 12] (a) Schematic front view of the curved body manipulator according to Example 2, (b) Schematic rear view of the curved body manipulator according to Example 2. [Figure 13] Schematic cross-sectional view of the curved body manipulator according to Example 2. [Figure 14] (a) Schematic cross-sectional view of the curved body manipulator according to Example 2, (b) Enlarged view of the curved body manipulator according to Example 2. [Figure 15] (a) Schematic perspective view of the central member according to Example 2, (b) Schematic cross-sectional view of the central member according to Example 2, (c) Schematic front view of the central member according to Example 2, (d) Schematic rear view of the central member according to Example 2. [Figure 16](a), (b), and (c) are schematic front views of each end member according to Embodiment 2. [Figure 17] (a), (b), and (c) are schematic front views of each guide ring according to Example 2. [Figure 18] (a) A schematic perspective view of the tubular member according to Example 2, and (b) A schematic front view of the tubular member according to Example 2. [Figure 19] (a), (b), (c) are schematic perspective views of each connecting member according to Embodiment 2, and (d), (e), (f) are schematic front views of each connecting member in the state in which the hollow members according to Embodiment 2 are joined. [Figure 20] (a) A schematic perspective view illustrating the buckling prevention part according to Example 2, and (b) An enlarged view illustrating the buckling prevention part according to Example 2. [Figure 21] (a) A cross-sectional view of the curved manipulator according to Example 2, and (b) an enlarged view of the curved manipulator according to Example 2. [Figure 22] (a) A schematic cross-sectional view of the curved manipulator according to Example 2, and (b) an enlarged view of the curved manipulator according to Example 2. [Figure 23] (a) A schematic perspective view of the inner member according to Embodiment 2, and (b) A schematic front view of the inner member according to Embodiment 2. [Figure 24] This is a schematic perspective view of the curved body robot according to Example 3. [Figure 25] This is a diagram illustrating the drive device according to Example 3. [Modes for carrying out the invention]

[0013] Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Note that the coordinate axes in the embodiments are common to all embodiments. Furthermore, the present invention is not limited to the configurations of each embodiment, but also encompasses embodiments derived from combinations of each embodiment.

[0014] [Example 1] Example 1 will be described with reference to Figures 1 to 10.

[0015] <Structure of a curved body manipulator> The structure of the curved body manipulator 10 will now be described. Figures 1(a) and 1(b) are schematic perspective views of the curved body manipulator 10. In Figure 1(b), the outer skin 12 of the curved body manipulator 10 is not shown. Figure 2(a) is a front view of the curved body manipulator 10, viewed from the side of the curved body 110, which will be described later. Figure 2(b) is a rear view of the curved body manipulator 10, viewed from the opposite side to Figure 2(a).

[0016] The curved body manipulator 10 includes a curved body 110 including a curved portion 13, an exterior member 11 as a frame to which the curved body 110 is attached, and drive shafts 16 (16a, 16b, 16c) as input units connected to the curved portion 13 of the curved body 110. The curved body manipulator 10 according to this embodiment has three drive shafts 16 (16a, 16b, 16c) as a plurality of input units.

[0017] Furthermore, a curved body can also be called a continuum, and a curved manipulator can also be called a continuum manipulator.

[0018] The curved section 13 includes a tip member 14 and a plurality of guide rings 15, and the tip member 14 and the plurality of guide rings 15 are covered by an outer shell 12. A central member 23 is housed inside the outer shell member 11. The curved manipulator 10 has a hollow structure in which a through hole 18 is formed that penetrates in the z-axis direction from the tip of the curved section 13 to the rear end of the central member 23.

[0019] The three drive shafts 16a to 16c can be driven independently of each other and are slid in the z-axis direction by manual or actuators, thereby curving the curved section 13. In other words, the curvature of the curved section 13 is controlled by the movement of each drive shaft 16a to 16c, each having a degree of freedom in the z-axis direction.

[0020] Here, in the curved body 110, the end supported by the exterior member 10 is called the rear end. The curved body 110 is inserted into the object from the front end opposite to the rear end. In the curved body 110, the front end can be called the distal end, and the rear end can be called the proximal end.

[0021] Next, the structure of the curved body manipulator 10 will be explained in more detail using Figures 3(a) to 3(c).

[0022] Figure 3(a) is a schematic cross-sectional view obtained by cutting through the center of the curved body manipulator 10 with a cross-section parallel to the yz plane. Figure 3(b) is an enlarged view of the dashed area A in Figure 3(a), and Figure 3(c) is an enlarged view of the dashed area B in Figure 3(a).

[0023] The curved section 13 has a tip member 14 and a plurality of guide rings 15 (9 in this embodiment) arranged at predetermined intervals. The tip member 14 is positioned at the tip of the curved section 13. The curved body 110 has a tubular member (longitudinal member) 22 having the same cross-sectional shape as the guide rings 15. The tubular member 22 is positioned at a predetermined distance from the guide rings 15 and on the rear end (proximal end) side of the curved section 13. The tubular member 22 is inserted into the exterior member 11, supported by the exterior member 11, and fixed to the exterior member 11.

[0024] Here, the curved body 110 is cylindrical in shape with a through hole 18 formed therein. In other words, the curved body 110 is cylindrical in shape. Let the central axis of the curved body 110 be the central axis CA. When the curved body 110 is straight, the central axis CA coincides with the central axis of the curved body manipulator 10.

[0025] Multiple drive shafts (16a to 16c) are arranged circumferentially around the central axis CA. Each of the drive shafts 16a to 16c has a flexible linear member 20 connected to the tip member 14 of the curved section 13, and a connecting member 21 connected to the linear member 20. The connecting member 21 can be said to be less deformable than the linear member 20. In other words, the deformation of the connecting member 21 when the same force is applied is smaller than that of the linear member 20. In this embodiment, since the drive shafts 16a to 16c have the same configuration, drive shaft 16a will be described as a representative.

[0026] The connecting member (intermediate member) 21 has a joint (fixing part) 21a and a force receiving part 21b. As will be described later, a linear member 20 is inseparably fixed to the joint 21a. The connecting member 21 is configured to be movable along the z-axis direction. The force receiving part 21b is exposed on the outside of the curved body manipulator 10 (outside the exterior member 11). When the force receiving part 21b receives a force (more specifically, an external force transmitted from the outside of the curved body manipulator 10), the connecting member 21 moves along the z-axis direction. The user can apply force to the force receiving part 21b manually or using a drive source such as a motor. A part of the linear member 20 fixed to the joint 21a can be called the joined part (connected part, fixed part) 20a.

[0027] In this embodiment, the connecting member 21 integrally includes a joint portion 21a, a force-receiving portion 21b, and a connecting portion that connects the joint portion 21a and the force-receiving portion 21b. However, the connecting member 21 may be constructed by combining multiple parts.

[0028] The direction in which the linear member 20 extends is called the extension direction. The extension direction of the linear member 20 coincides with the longitudinal direction of the curved body 110. In the state shown in Figures 3(a) and (b) (when the curved body 110 is straight), the extension direction of the linear member 20 coincides with the z-axis direction.

[0029] In the direction perpendicular to the extension direction (y-axis direction in Figure 3(a)), the force-receiving portion 21b is positioned further from the linear member 20 than the joint portion 21a. On the other hand, in the direction perpendicular to the central axis CA of the curved body 110 (y-axis direction in Figure 3(a)), the joint portion 21a is positioned closer to the central axis CA than the force-receiving portion 21b.

[0030] As the connecting member 21 moves along the z-axis direction, the linear member 20 is moved integrally in the extension direction. As the linear member 20 moves in the extension direction, the curved portion 13 is curved.

[0031] As described above, the curved body manipulator 10 includes multiple drive shafts (16a to 16c). Each drive shaft can also be distinguished by a number such as "first" or "second". For example, drive shaft 16a can be called the first drive shaft (first input). In this case, the linear member 20 of drive shaft 16a can be called the first linear member, and the connecting member 21 can be called the first connecting member. Furthermore, the extension direction of the first linear member can be called the first extension direction, the movement direction of the first connecting member can be called the first movement direction, the fixed part of the first connecting member can be called the first fixed part, and the force receiving part of the first connecting member can be called the first force receiving part. Similarly, drive shaft 16b can be called the second drive shaft (second input), and drive shaft 16c can be called the third drive shaft (third input).

[0032] A central member 23 is positioned inside the exterior member 11, and the connecting member 21 is slidably supported on its side by the central member 23. The central member 23 will be explained using Figures 4(a) to 4(c). Figure 4(a) is a schematic front view of the central member 23, (b) is a schematic cross-sectional view of the central member 23 at the EE cross-section, and (c) is a schematic rear view of the central member 23.

[0033] The central member 23 has radially extending grooves (guide grooves) 23a, 23b, and 23c with a width W, spaced at 120-degree intervals, and a through hole 23d is provided at its center. The radial center coincides with the central axis CA of the curved body 110. The through hole 23d forms part of the through hole 18.

[0034] The connecting members 21 for the respective drive shafts 16a to 16c fit into grooves 23a, 23b, and 23c. Groove 23a corresponds to drive shaft 23a, groove 23b to drive shaft 23b, and groove 23c to drive shaft 23c. In Figures 4(a) to (c), groove 23a is positioned along the y-axis direction. Since grooves 23a, 23b, and 23c have the same shape, groove 23a will be described as a representative example.

[0035] As shown in Figure 4(b), groove 23a has a region L3 with a radial depth D1 and a region L4 with a radial depth D2, where D1 > D2.

[0036] As will be described later, the connecting member 21 has a plate-shaped portion and a plate thickness (thickness) that is slightly smaller than the groove width W.

[0037] As shown in Figure 3(c), when the connecting member 21 is not subjected to any force and the curved body 110 is straight, the joint portion 21a of the connecting member 21 is in a neutral position. This state is called the neutral state. The joint portion 21a can move L1 in the positive z-axis direction and L2 in the negative z-axis direction from the neutral position. Furthermore, in the radial direction, the radial movement of the connecting member 21 is restricted because the outer covering member 11 is fitted to cover the 23a, 23b, and 23c of the central member 23 from the outside. As a result, the circumferential (thickness direction) and radial movement of the connecting member 21 is constrained. On the other hand, the movement in the z-axis direction is limited to a predetermined range (L1 + L2).

[0038] In other words, the central member 23 and the outer casing member 11 function as guide members that guide the connecting member 21. Therefore, the central member 23 can be called the first guide member, and the outer casing member 11 can be called the second guide member.

[0039] When the force receiving portion 21b receives a force, the connecting member 21 is guided by the central member 23 and the outer casing member 11 and moves in the direction of movement (in this embodiment, the z-axis direction). As a result, the linear member 20 fixed to the fixing portion 21a moves in the stretching direction, and the curved portion 13 is curved. The central member 23 and the outer casing member 11 allow the connecting member 21 to move in the direction of movement, while restricting its movement in a direction intersecting the direction of movement (preferably perpendicular). This ensures that the connecting member 21 moves precisely in the direction of movement.

[0040] Specifically, the central member 23 suppresses the movement of the connecting member 21 in the circumferential direction around the central axis CA. The central member 23 suppresses the movement of the connecting member 21 in a direction intersecting the extension direction of the linear member 20, thereby suppressing the bending of the linear member 22. In addition, the central member 23 suppresses the rotation of the connecting member 21 around the linear member 20, thereby suppressing the twisting of the linear member 20. On the other hand, the outer casing member 11 and the central member 23 suppress the movement of the connecting member 21 in the radial direction around the central axis CA. The outer casing member 11 and the central member 23 (ends of grooves 23a, 23b, and 23c) suppress the movement of the connecting member 21 in a direction intersecting the extension direction of the linear member 20, thereby suppressing the bending (flexing) of the linear member 22.

[0041] As a result, stick-slip of the connecting member 21 is suppressed, and the connecting member 21 can slide smoothly relative to the central member 23. In addition, since movement of the connecting member 21 in a direction intersecting the direction of movement is suppressed, bending of the linear member 20 is suppressed.

[0042] The tip member 14 and the guide ring 15 will be explained using Figures 5(a) and 5(b). In this embodiment, the tip member 14 and the guide ring 15 have the same shape. Figure 5(a) is a schematic front view of the tip member 14 and the guide ring 15, and (b) is a schematic side view of the tip member 14 and the guide ring 15.

[0043] The tip member 14 and the guide ring 15 have an annular shape with a through hole 15d, and have three holes 15a, 15b, and 15c at the same radius r from the center. Each of the three holes 15a, 15b, and 15c is into which the respective linear members 20 of the drive shafts 16a to 16c are inserted. In this embodiment, the three holes 15a to 15c are arranged at equal intervals so as to divide a circle of radius r equally, and the angle α1 = α2 = 120 degrees in the figure. The through hole 15d forms part of the through hole 18.

[0044] The tubular member 22 of the curved body 110 will be explained using Figures 6(a) and (b). Figure 6(a) is a schematic front view of the tubular member 22, and (b) is a schematic side view of the tubular member 22. In Figure 6(a), the connecting member 21 and the linear member 20 are shown by dotted lines.

[0045] Similar to the tip member 14 and the guide ring 15, the tubular member 22 has an annular shape with a through hole 22d. The tubular member 22 is flexible and has three holes 22a, 22b, and 22c at the same radius r from its center. Each of the linear members 20 of the drive shafts 16a to 16c is inserted into each of the holes 22a to 22c. The through hole 22d forms part of the through hole 18. Furthermore, the tubular member 22 is located at the proximal end of the curved body 110, and the holes 22a to 22c are also located at the proximal end of the curved body 110.

[0046] The other end (proximal end) of the linear member 20 is joined to the connecting member 21 at the joint 21a of the connecting member 21. Here, the linear member 20 of the drive shaft 16a is positioned to pass through the holes 14a, 15a, and 22a of the tip member 14, guide ring 15, and tubular member 22, respectively. The linear member 20 of the drive shaft 16b is positioned to pass through the holes 14b, 15b, and 22b of the tip member 14, guide ring 15, and tubular member 22, respectively. The linear member 20 of the drive shaft 16c is positioned to pass through the holes 14c, 15c, and 22c of the tip member 14, guide ring 15, and tubular member 22, respectively.

[0047] As shown in Figure 3(b), the curved body 110 has a tubular inner shell 19 and a tubular outer shell 12. The inner shell 19 and outer shell 12 are flexible.

[0048] The tip member 14 and the guide ring 15 are positioned between the inner skin 19 and the outer skin 12. The inner wall surfaces of the through holes 15d of the tip member 14 and the guide ring 15 are joined to the outer surface (outer surface) of the inner skin 19. On the other hand, the outer skin 12 is positioned on the outer surface (outer surface) of the tip member 14 and the guide ring 15.

[0049] Each linear member 20 of the drive shafts 16a to 16c has one end (the distal end) fixed to the holes 15a to 15c of the tip member 14, passes through the holes 15a to 15c of the guide ring 15, and is positioned to slide relative to the holes of the guide ring 15. The linear member 20 passes through the holes 22a to 22c of the tubular member 22 in the negative direction (proximal side) of the z axis and reaches the inside of the outer casing member 11. A connecting member 21 is positioned inside the outer casing member 11.

[0050] The connecting member 21 will be explained using Figures 7(a) and 7(b). Figure 7(a) is a schematic front view of the connecting member 21, and (b) is a schematic side view of the connecting member 21.

[0051] As shown in Figures 7(a) and 7(b), the connecting member 21 has a plate-shaped (sheet-shaped) plate portion (sheet portion) 21c. In this embodiment, the entire connecting member 21 can be said to be a plate-shaped plate portion 21c, but the plate portion 21c may be only a part of the connecting member 21.

[0052] Here, a plate shape means that, in the thickness direction, width direction, and length direction which are perpendicular to each other, the length in the width direction (width, second length, first surface direction) is longer than the length in the thickness direction (thickness, first length), and the length in the length direction (third length, second surface direction) is greater than or equal to the length in the width direction. In other words, the thickness of the plate-shaped portion of the connecting member 21 (the entire connecting member 21 in this embodiment) is the shortest length among the lengths in the three perpendicular directions. The direction perpendicular to the thickness direction can also be called the surface direction. In Figures 7(a) and (b), the thickness direction of the plate portion 21c of the connecting member 21 is the x-axis direction, the width direction is the y-axis direction, and the length direction is the z-axis direction.

[0053] The connecting member 21 has a surface (a surface extending in the surface direction) 21c1 perpendicular to the thickness direction. The direction of movement of the connecting member 21 is the z-axis direction, and the connecting member 21 is positioned so that the surface 21c1 is aligned with the direction of movement. The central member 23 contacts the pair of surfaces 21c1 in the groove 23 and guides the connecting member 21. In this way, the central member 23 guides the surface 21c1, allowing the connecting member 21 to move stably in the direction of movement.

[0054] In this embodiment, the connecting member 21 has an L-shape. As described above, the connecting member 21 has a joint portion 21a and a force receiving portion 21b. In the direction of movement of the connecting member 21 (in the z-axis direction), the force receiving portion 21b is positioned away from the joint portion 21a (at a position offset from the joint portion 21a).

[0055] On the other hand, the connecting member 21 has a plate portion 21c positioned near the linear member 20. The joint portion 21a is positioned at the end of the plate portion 21c. In the drive shafts 16a to 16c, the connecting member 21 is positioned such that its surface 21c1 faces in the circumferential direction around the central axis CA, and the surfaces 21c1 are arranged radially from the central axis CA. By positioning the drive shafts 16a to 16c in this manner, the joint portion 21a can be positioned close to the central axis CA.

[0056] When the joint 21a is positioned near the central axis CA, the distance between the connecting members 21 of the drive shafts 16a to 16c becomes shorter. However, because the connecting members 21 have a plate portion 21c, the connecting members 21 can be positioned close together in a small space. Furthermore, the end of the plate portion 21c where the joint 21a is positioned has a flat plate shape. Therefore, the connecting members 21 can be positioned even closer together in a smaller space.

[0057] As shown in Figure 3(a), the joint 21a is positioned such that the linear member 20 extends in a straight line between the curved body 110 and the joint 21a. A portion of the linear member 20 located between the curved body 110 and the joint 21a can be called the intermediate portion 20b. In this case, with the linear member 20 being a perfect straight line as the reference (0°), the bending angle of the intermediate portion 20b of the linear member 20 is preferably within 10°, and more preferably within 5°.

[0058] On the other hand, Figure 6(a) can be described as a view along the direction of movement of the connecting member 21, or a view along the central axis CA or the extension direction of the linear member 20 when the curved body 110 is in a straight line. As described above, each of the linear members 20 of the drive shafts 16a to 16c is inserted into one of the multiple holes (22a to 22c) of the tubular member 22 of the curved body 110. For example, for the drive shaft 16a, the linear member 20 is inserted into hole 22a, which is one of the multiple holes (22a to 22c) of the tubular member 22 of the curved body 110. As shown in Figure 6(a), the joint 21a of hole 22a and the drive shaft 16a, and the fixed portion 20a of hole 22a and the drive shaft 16a overlap at least partially. The relationship between hole 22b and drive shaft 16b, and between hole 22c and drive shaft 16c are similar.

[0059] When the linear member 20 is bent between the curved body 110 and the joint 21a, when the connecting member 21 moves the linear member 20 in the direction of movement via the joint 21a, a part of the linear member 20 (the intermediate portion 20b) also moves in a direction intersecting the extension direction of the linear member 20. Furthermore, the trajectory of the linear member 20 and the frictional force between the connecting member 21 and the member guiding the linear member 20 differ depending on whether the connecting member 21 is pushing or pulling the linear member 20.

[0060] On the other hand, because the linear member 20 extends linearly from the joint 21a to the curved body 110, bending of the linear member 20 is suppressed, and when the connecting member 21 moves in the direction of movement, movement of the linear member 20 in a direction intersecting the extension direction is suppressed. In addition, differences in the trajectory of the linear member 20 and the frictional force between the linear member 20 and the member guiding the linear member 20 are suppressed when the connecting member 21 pushes the linear member 20 and when it pulls it.

[0061] Since the curved portion 13 is curved as the linear member 20 moves in the extension direction, the curved portion 13 can be curved efficiently and accurately by moving the linear member 20 linearly from the joint portion 21a toward the curved body 110.

[0062] Next, the method of joining the linear member 20 and the connecting member 21 will be explained using Figures 8(a) to (d). Figure 8(a) is a schematic front view of the state in which the linear member 20 is joined to the connecting member 21, (b) is a schematic side view of the state in which the linear member 20 is joined to the connecting member 21, (c) is an enlarged view of the dashed area F, and (d) is an enlarged view of the dashed area F. Note that the configuration shown in Figure 8(d) is a modified example of the configuration shown in Figure 8(c).

[0063] The fixed portion 20a of the linear member 20 is joined to the joint portion (connecting portion, fixing portion) 21a of the connecting member 21. It is possible to join only the portion where the linear member 20 and the connecting member 21 touch, but as shown in Figure 8(c), the joining material 24 can be used to join the two more firmly.

[0064] As the linear member 20, a wire made of piano wire, stainless steel spring wire, nickel-titanium alloy wire, etc., can be used. The connecting member 21 can be made of metals such as iron, stainless steel, copper, and aluminum alloy, resins such as polycarbonate, PEEK (polyether ether ketone), and ABS, or ceramics such as alumina and zirconia. As the joining material 24, epoxy adhesives or UV-curing resins can be used. If the connecting member 21 is made of metal, the linear member 20 and the connecting member 21 can be joined by welding or brazing, in which case the joining material 24 can be weld metal or brazing material.

[0065] Furthermore, the connecting member 21 and the linear member 20 can also be joined as shown in Figure 8(d). A through hole 21c is provided in the joint portion 21a of the connecting member 21, penetrating the joint portion 21a in the z-axis direction, and the two can be joined by inserting the linear member 20 into the through hole 21c. After inserting the linear member 20, the linear member 20 may be fixed using an anaerobic adhesive or a super glue, or the linear member 20 may be fixed by deforming the joint portion 21a.

[0066] With the above configuration, by attaching an actuator or a manually operated handle to the force receiving portion 21b provided at the end of the connecting member 21, the drive shafts 16a to 16c can be pushed and pulled independently in the z-axis direction relative to each other.

[0067] <Bending motion> Next, the bending operation of the curved portion 13 of the curved body manipulator 10 by driving the drive shafts 16a to 16c will be explained using Figures 9 and 10. Figure 9 is a schematic perspective view of the curved body manipulator 10 with the curved portion 13 bent. Figure 10 is a schematic cross-sectional view of the curved body manipulator 10 with the curved portion 13 bent. Figure 10 is a cross-sectional view passing through the center of the curved body manipulator 10.

[0068] By appropriately pushing and pulling the drive shafts 16a to 16c, the curved section 13 can be bent in the yz plane while maintaining a constant curvature of the curved section 13. When the curved section 13 is in a horizontal (straight) state, the position of the ends of each drive shaft 16a to 16c in the z-axis direction is denoted as Zo, and the z-axis displacements of each drive shaft 16a to 16c are denoted as Za to Zc, respectively. In the state shown in Figure 10, the bending motion is achieved by pulling drive shaft 16a in the negative z-axis direction by Za, and pushing drive shafts 16b and 16c in the positive z-axis direction by Zb and Zc, respectively.

[0069] Here, if we let R be the radius of curvature passing through the center of the curved section 13, and S be the arc length of this section, then we obtain the following equation. S=Rθ (Formula 1) If the radii of curvature of the curved portion 13 at positions corresponding to the drive shafts 16a, 16b, and 16c are Ra, Rb, and Rc, respectively, then the following equation is obtained based on the geometric relationship shown in Figure 5(a). Ra=Rr (formula 2) Rb=R+r / 2 (Formula 3) Rc=R+r / 2 (Formula 4) Based on the relationship between the arc length of the curved portion 13 of the drive shafts 16a, 16b, and 16c and the displacement of each drive shaft 6a, 16b, and 16c, the following equation is obtained. Raθ = S - Za (Equation 5) Rbθ = S + Zb (Equation 6) Rcθ=S+Zc (Formula 7) By substituting (Equation 1) to (Equation 4) into (Equation 5) to (Equation 7), the displacement of each drive shaft can be calculated as follows. Za = rθ (Equation 8) Zb=rθ / 2 (Formula 9) Zc=rθ / 2 (Equation 10) From equations (8) to (10), the relationship between the displacements of each drive shaft 16a, 16b, and 16c when the curved section 13 is curved in the yz plane can be expressed by the following equation. Za=2Zb=2Zc (Formula 11) Similarly, by appropriately setting the z-axis displacement of the drive shafts 16a, 16b, and 16c, it is possible to curve the curved portion 13 in any plane including the Z-axis. That is, while maintaining the radius of curvature R of the curved portion 13, it is possible to perform a pivoting motion around the z-axis. Therefore, it can be said that the curved portion 13 of the curved body manipulator 10 in this embodiment has two degrees of freedom: curvature and pivoting.

[0070] As described above, thrust can be efficiently transmitted from the connecting member 21 to the linear member 20 which is positioned in the curved section 13 at a radius r. When pushing or pulling the linear member 20 to curve the curved section 13, the linear member 20 is positioned in a straight line from the tubular member 22 to the point where it is joined to the connecting member 21 (joint 21a). Therefore, since the path is the same when pushing and pulling the linear member 20, there is less difference between the dynamic characteristics when pushing the linear member 20 and the dynamic characteristics when pulling the linear member 20.

[0071] Furthermore, because the connecting member 21 is plate-shaped, it can be easily manufactured by machining, injection molding, die casting, press working, surface grinding, etc., and the connecting member 21 can slide smoothly with high precision. Therefore, it is possible to reduce variations in control performance when pushing and pulling the linear member 20.

[0072] In addition, according to the configuration of this embodiment, thrust can be easily transmitted to linear members 20 arranged in a confined space. For example, when the curved body manipulator 10 is used as a transnasal endoscope for medical purposes, it is assumed that the diameter of the outer skin 12 is about 5 mm, the diameter of the inner skin 19 is about 3 mm, and the radius r in which the linear members 20 are arranged is about 2 mm. It is not easy to independently transmit thrust to multiple linear members 20 arranged in such a confined space. However, by transmitting thrust using a connecting member 21 guided by the central member 23, the force receiving part 21b for transmitting force can be positioned on a circle with a radius sufficiently larger than the radius r in which the linear members 20 are arranged.

[0073] Therefore, when transmitting thrust to each drive shaft 16a to 16c using actuators such as motors and handles, the degree of design freedom regarding the arrangement and size of the actuators such as motors and handles is increased, making it easier to transmit force into confined spaces.

[0074] Furthermore, in this embodiment, the curved manipulator 10 allows various tools to be inserted from the central member 23 towards the curved portion 13 using the through hole 18.

[0075] For example, by inserting a small camera into the through-hole 18, the inside of the object into which the curved body 110 is inserted can be observed. On the other hand, when inserting a small camera with an actuator such as a motor connected to the force receiving portion 21b, the camera's casing may come into contact with the linear member 20, causing the camera's signal line to short-circuit with the actuator's ground, which may result in phenomena such as noise generation.

[0076] Therefore, in this embodiment, the connecting member 21 can be made of a non-conductive material, or even if it is made of a conductive material, the surface can be painted or coated with a non-conductive material to electrically insulate the linear member 20 from the actuator. For example, if the connecting member 21 is made of an aluminum alloy, insulation can be achieved by applying anodizing treatment to the area near the force-receiving portion 21b.

[0077] Furthermore, when the curved manipulator 110 is used in a medical device, in addition to a camera, forceps, biopsy tools, etc., can be inserted into the through-hole 18 to perform medical procedures in narrow spaces within the body.

[0078] As described above, in this embodiment, since the linear members 20 are arranged in a straight line, the risk of buckling of the linear members 20 is reduced, and the frictional force associated with driving the linear members 20 can be reduced or stabilized. By appropriately setting the dimensions of the thickness of the connecting member 20 and the width W of the grooves (23a to 23c) of the central member 23, and by making the gap between the connecting member 20 and the grooves (23a to 23c) an appropriate size, the frictional force can be appropriately set.

[0079] Furthermore, by appropriately selecting the materials for the central member 23 and the connecting member 21, even if the gap between the grooves 23a, 23b, and 23c and the connecting member 21 is set to be small, the connecting member 21 can slide smoothly inside the grooves 23a, 23b, and 23c. For example, when selecting a metal material such as stainless steel for the connecting member 21 in order to join the linear member 20 and the connecting member 21 by welding, it is preferable to form the central member 23 from a resin material such as polyacetal, which has high sliding properties. As a result, the magnitudes of the maximum static friction force and the kinetic friction force become close, and the connecting member 21 is stably supported and slidable by the central member 23.

[0080] In this embodiment, a configuration was described in which the curved section 13 can perform two degrees of freedom of movement (bending and pivoting) in response to three degrees of freedom of input using three drive shafts 16a to 16c. In contrast, the inner skin 19 and outer skin 12 can be formed from an expandable material, and the curved section 13 can be expanded and contracted in the z-axis direction by pushing and pulling the three drive shafts 16a to 16c in the same direction. This provides a curved body manipulator 10 with a total of three degrees of freedom.

[0081] As described above, according to this embodiment, bending of the linear member 20 can be suppressed.

[0082] [Example 2] The curved body manipulator (continuous body manipulator) 50 according to Example 2 will be explained using Figures 11 to 23.

[0083] Figure 11(a) is a schematic perspective view of the curved manipulator 50, (b) is a schematic perspective view of the curved portion 53 of the curved manipulator 50 with the outer skin 52 hidden, (c) is a schematic perspective view with the outer skin 52 and exterior member 51 hidden, and (d) is an enlarged view of the dashed area C. Figure 12(a) is a schematic front view of the curved manipulator 50, and (b) is a schematic rear view of the curved manipulator 50. Figure 13 is a schematic cross-sectional view of the curved manipulator 50 taken by cutting through the center of the curved manipulator 50 with a cross section parallel to the yz plane. Figure 14(a) is a schematic cross-sectional view of the curved manipulator 50 taken by cutting at the HH cross section in Figure 13, and (b) is an enlarged view of the dashed area I.

[0084] The curved body manipulator 50 includes a curved body 210 including a curved portion 53, an exterior member (frame) 51 to which the curved body 210 is attached, and drive shafts (1a, 1b, 1c, 2a, 2b, 2c, 3a, 3b, 3c) as input parts connected to the curved portion 53 of the curved body 210. The curved body manipulator 50 according to this embodiment has nine drive shafts (input parts) 1a, 1b, 1c, 2a, 2b, 2c, 3a, 3b, 3c as a plurality of drive shafts (input parts).

[0085] The functions of drive shafts 1a-1c, 2a-2c, and 3a-3c are the same as those of drive shafts 16a-16c in Embodiment 1. In other words, drive shafts 1a-1c, 2a-2c, and 3a-3c can be driven independently of each other and are slid in the z-axis direction by manual operation or an actuator, thereby curving the curved section 53. In other words, the curvature of the curved section 53 is controlled by the movement of drive shafts 1a-1c, 2a-2c, and 3a-3c, each having degrees of freedom in the z-axis direction.

[0086] Similar to Embodiment 1, the drive shafts 1a-1c, 2a-2c, and 3a-3c have connecting members 71, 72, and 73, which correspond to the connecting member 21 in Embodiment 1. In the drive shafts 1a-1c, 2a-2c, and 3a-3c, the linear member 77, which corresponds to the linear member 20 in Embodiment 1, is driven in the extension direction by pushing and pulling the connecting members 71-73 in the z-axis direction.

[0087] Next, the structure of the curved section 53 will be described. As shown in Figure 11(d), the curved section 53 has three sections: the first section 61, the second section 62, and the third section 63. The configuration of the first section 61, the second section 62, and the third section 63 will be described in detail.

[0088] The first section 61 has a tip member 64 and a plurality of guide rings 65 (9 in this embodiment) arranged at predetermined intervals. Similarly, the second section 62 has a tip member 66 and a plurality of guide rings 67 (9 in this embodiment) arranged at predetermined intervals. The third section 63 has a tip member 68 and a plurality of guide rings 69 (4 in this embodiment) arranged at predetermined intervals.

[0089] Details of each end member 64, 66, 68 and guide rings 65, 67, 69 will be explained using Figures 16 and 17.

[0090] Figure 16(a) is a schematic front view of the tip member 64, (b) is a schematic front view of the tip member 66, and (c) is a schematic front view of the tip member 68. Figure 17(a) is a schematic front view of the guide ring 65, (b) is a schematic front view of the guide ring 67, and (c) is a schematic front view of the guide ring 69.

[0091] Here, the cross-sectional shapes of the tip member 64 and guide ring 65, the tip member 66 and guide ring 67, and the tip member 68 and guide ring 69 are identical, but as shown in Figure 11(d), their lengths in the z-axis direction are different.

[0092] As shown in Figure 16(a), the tip member 64 has an annular shape with a through hole 64j, and has nine holes 64a to 64i at the same radius r from its center. In this embodiment, the nine holes 64a to 64i are arranged at equal intervals so as to divide a circle of radius r equally, and the angle γ in the figure is 40 degrees.

[0093] As shown in Figure 17(a), the guide ring 65 has an annular shape with a through hole 65j, and has nine holes 65a to 65i located at the same radius r from its center. In this embodiment, the coordinate positions in the xy plane of the nine holes 65a to 65i and the through hole 65j are the same as the coordinate positions in the xy plane of the holes 64a to 64i and the through hole 64j.

[0094] As shown in Figure 16(b), the tip member 66 has an annular shape with a through hole 66j, and has six holes 66b, 66c, 66e, 66f, 66h, and 66i at the same radial position r from its center. In this embodiment, the coordinate positions in the xy plane of the six holes 66b, 66c, 66e, 66f, 66h, and 66i, and the through hole 66j, are the same as the coordinate positions in the xy plane of the holes 64b, 64c, 64e, 64f, 64h, and 64i, and the through hole 64j.

[0095] As shown in Figure 17(b), the guide ring 67 has an annular shape with a through hole 67j, and has six holes 67b, 67c, 67e, 67f, 67h, and 67i at the same radial position r from its center. In this embodiment, the coordinate positions in the xy plane of the six holes 67b, 67c, 67e, 67f, 67h, and 67i, and the through hole 67j, are the same as the coordinate positions in the xy plane of the holes 66b, 66c, 66e, 66f, 66h, and 66i, and the through hole 66j.

[0096] As shown in Figure 16(c), the tip member 68 has an annular shape with a through hole 68j, and has three holes 68c, 68f, and 68i at the same radius r from its center. In this embodiment, the coordinate positions in the xy plane of the three holes 68c, 68f, and 68i and the through hole 68j are the same as the coordinate positions in the xy plane of the holes 64c, 64f, 64i, and the through hole 64j.

[0097] As shown in Figure 17(c), the guide ring 69 has an annular shape with a through hole 69j, and has three holes 69c, 69f, and 69i at the same radius r from its center. In this embodiment, the coordinate positions in the xy plane of the three holes 69c, 69f, and 69i and the through hole 69j are the same as the coordinate positions in the xy plane of the holes 69c, 69f, 69i and the through hole 69j.

[0098] The curved body 210 has a tubular member 70 adjacent to the curved portion 53. The tubular member 70 is positioned so as to create a predetermined gap between it and the guide ring 65. The tubular member 70 is made of a flexible material and, as shown in Figure 13, a portion of it is supported by the exterior member 51, thereby forming a driven curved portion 54 in the curved body 210.

[0099] Figure 18(a) is a schematic perspective view of the tubular member 70, and (b) is a schematic front view of the tubular member 70. In Figure 18(b), the tubular member 70 of the curved body 210 has an annular cross-sectional shape with a through hole 70j, and has nine holes 70a to 70i at the same radius r from its center. In this embodiment, the coordinate positions in the xy plane of the nine holes 70a to 70i and the through hole 70j are the same as the coordinate positions in the xy plane of the holes 64a to 64i and the through hole 64j. The tubular member 70 is positioned at the proximal end of the curved body 210, similar to the tubular member 22 in Embodiment 1.

[0100] As will be described later, the connecting members 71, 72, and 73 have joints 71a, 72a, and 73a to which the linear member 77 is fixed, and the linear member 77 has a fixed portion 77a to which it is fixed to the joints 71a, 72a, and 73a. The relationship between the joints 71a, 72a, and 73a, the fixed portion 77a, and the nine holes 70a to 70i is the same as the relationship shown in Embodiment 1.

[0101] The curved body 210 has a tubular and flexible inner skin 56 and an outer skin 52. The inner wall surfaces of the tip members 64, 66, 68, guide rings 65, 67, 69, and through holes 64j, 66j, 68j, 65j, 67j, 69j, and 70j of the tubular member 70 are joined to the outer circumferential side surface of the inner skin 56. On the other hand, the outer skin 52 is fixed to the outer circumferential side surface of the curved portion 53, including the tip members 64, 66, 68 and the guide rings 65, 67, 69, so as to partially cover the outer circumferential side surface of the tubular member 70.

[0102] Next, the arrangement of the linear members 77 will be described. To drive the first section 61, the second section 62, and the third section 63, three linear members 77 are used for each section, for a total of nine linear members 77.

[0103] To drive the first section 61 in a curved manner, one end of each linear member 77 of the drive shafts 1a, 1b, and 1c is fixed to the holes 64a, 64d, and 64g of the end member 64, respectively. Each linear member 77 is pushed and pulled in the z-axis direction. Each linear member 77 passes through the holes 65a, 65d, and 65g of the guide ring 65 and the holes 70a, 70d, and 70g of the tubular member 70, and is guided by these holes.

[0104] To drive the second section 62 in a curved direction, one end of each linear member 77 of the drive shafts 2a, 2b, and 2c is fixed to the holes 66b, 66e, and 66h of the end member 66, respectively. Each linear member 77 is pushed and pulled in the z-axis direction. Each linear member 77 passes through the holes 67b, 67e, and 67h of the guide ring 67, the holes 64b, 64e, and 64h of the end member 64 of the first section, and the holes 65b, 65e, and 65h of the guide ring 65 of the first section, and is guided by these holes. Each linear member 77 also passes through the holes 70b, 70e, and 70h of the tubular member 70, and is guided by these holes.

[0105] To drive the third section 63 in a curved manner, one end of each linear member 77 of the drive shafts 3a, 3b, and 3c is fixed to the holes 68c, 68f, and 68i of the end member 68, respectively. Each linear member 77 is pushed and pulled in the z-axis direction. Each linear member 77 passes through the holes 69c, 69f, and 69i of the guide ring 69, the holes 66c, 66f, and 66i of the end member 66 of the second section, and the holes 67c, 67f, and 67i of the guide ring 67 of the second section, and is guided by these holes. Each linear member 77 also passes through the holes 64c, 64f, and 64i of the end member 64 of the first section, the holes 65c, 65f, and 65i of the guide ring 65 of the first section, and the holes 70c, 70f, and 70i of the tubular member 70, and is guided by these holes.

[0106] According to the above configuration, by pushing and pulling the linear members 77 of the drive shafts 1a, 1b, and 1c, it is possible to perform two degrees of freedom of movement, bending and pivoting, on the first section 61 using a mechanism similar to that described in Embodiment 1. Similarly, by pushing and pulling the linear members 77 of the drive shafts 2a to 3c, it is possible to perform two degrees of freedom of movement, bending and pivoting, on the second and third sections 62 and 63, respectively. In other words, in this embodiment, the bending section 53 functions as a six-degree-of-freedom manipulator.

[0107] Next, the arrangement and shape of the connecting members for transmitting thrust to each drive shaft will be described. In this embodiment, drive shaft 3b has a connecting member 72, and drive shaft 2b has a connecting member 73. The other seven drive shafts (1a to 1c, 2a, 2c, 3a, 3c) have a connecting member 71. Although the connecting members 71, 72, and 73 have different shapes, they have the same function as the connecting member 21 in Embodiment 1 in terms of moving the linear member 77.

[0108] The arrangement of the connecting members 71 to 73 corresponding to each of the drive shafts (1a to 1c, 2a to 2c, 3a to 3c) is as shown in Figure 14(a). The angles β1 = 40 degrees and β2 = β3 = 30 degrees shown in Figure 14(a).

[0109] Here, the details of the connecting members 71, 72, and 73 will be explained using Figure 19. Figure 19(a) is a schematic perspective view of connecting member 71, (b) is a schematic perspective view of connecting member 72, and (c) is a schematic perspective view of connecting member 73. Also, Figure 19(d) is a schematic front view of connecting member 71 to which the hollow member 75 is joined, (e) is a schematic front view of connecting member 71 to which the hollow member 75 is joined, and (f) is a schematic front view of connecting member 71 to which the hollow member 75 is joined.

[0110] Similar to the connecting member 21 in Example 1, the connecting members 71 to 73 each have joint portions 71a to 73a and force-receiving portions 71b to 73b. The function of the joint portions 71a to 73a is the same as that of 21a in Example 1, and the function of the force-receiving portions 71b to 73b is the same as that of the force-receiving portion 21b in Example 1.

[0111] Furthermore, similar to how the connecting member 21 of Embodiment 1 had a plate portion 21c, the connecting members 71, 72, and 73 have plate portions 71c, 72c, and 73c, respectively. The plate portion 71c has a plate shape (flat plate shape) parallel to the plane. On the other hand, parts of the plate portions 72c and 73c of the connecting members 72 and 73 are bent to form bent portions 72f and 73f. By bending the plate portions 72c and 73c, the connecting members 72 and 73 have plate shapes that are bent at angles δ2 and δ3, respectively, with respect to the flat plate portion where the joint portions 72a and 73a are formed at the ends. δ2 = δ3 = 10 degrees, and the connecting members 72 and 73 are bent in opposite directions around the z axis with respect to the yz plane.

[0112] Furthermore, each connecting member 71 to 73 is provided with inclined portions 71d, 72d, and 73d, and the connecting members 71 to 73 have a rectangular shape with a part of it, more specifically, an L-shaped corner cut out. The inclined portions 71d, 72d, and 73d are inclined so that they approach the central axis CA from the proximal end to the distal end in a direction perpendicular to the central axis CA. On the other hand, the outer casing member 51 has a tapered shape to match this inclination. This makes it possible to minimize the volume of the outer casing member 51 while ensuring the rigidity of the connecting members 71 to 73 in the z-axis direction, thereby improving space efficiency.

[0113] In addition, each connecting member 71 to 73 is provided with an inclined portion 71e to 73e, which is a rectangular shape with a portion cut out. This makes it easier to avoid interference with the central member 57 when each connecting member 71 to 73 is driven in the negative direction of the z axis.

[0114] Similar to Embodiment 1, as the connecting members 71-73 move in the direction of movement, the linear member 70 moves in the direction of extension, and the curved portion 53 is curved. The curved body manipulator 50 has a central member 57 that corresponds to the central member 23 in Embodiment 1. The curved body manipulator 50 uses the central member 57 as a guide member to guide the connecting members 71-73 in the direction of movement (z-axis direction). This makes it possible to stably transmit the thrust input to the force receiving portions 71b-73b to the joint portions 71a-73a.

[0115] Figure 15(a) is a schematic perspective view of the central member 57, (b) is a schematic cross-sectional view of the central member 57 taken from a cross-section parallel to the yz plane passing through the center of the central member 57, (c) is a schematic front view of the central member 57, and (d) is a schematic rear view of the central member 57.

[0116] The central member 57 has nine grooves 57c having regions 57c1 and 57c2, and on its side there is an insertion opening 57a with a through hole 57b, and a support portion 57e for fitting and supporting the straight pipe 59 described later.

[0117] The groove 57c is provided along the radial direction. Regions 57c1 and 57c2 have different radial depths, with region 57c1 being deeper than region 57c2. Connecting members 71, 72, and 73 are fitted into regions 57c1 and 57c2 of the groove 57c, and the distal ends of connecting members 71, 72, and 73, where the joint portions 71a to 73a are located, are guided in the z-axis direction by the portion of region 57c1. The surfaces 71c1, 72c1, and 73c1 of the connecting members 71, 72, and 73, which are perpendicular to the thickness direction, are slidably supported by the central member 57.

[0118] Similar to Embodiment 1, the width of the groove 57c, the gap between the connecting members 71, 72, and 73, and the materials of the central member 57 and the connecting members 71, 72, and 73 are determined so that the central member 57 smoothly guides the connecting members 71 to 73. Also, similar to Embodiment 1, the side surface of the central member 57 is covered by the inner wall of the exterior member 51, thereby restraining the connecting members 71 to 73 from moving radially.

[0119] Next, we will describe a method for fixing the other end of each linear member 77, which is fixed to the tip members 64, 66, and 68, to the connecting members 71 to 73.

[0120] As shown in Figures 19(d) to (f), hollow members 75 are joined to the joints 71a to 73a of connecting members 71 to 73 via a joining material 74. Here, the hollow member 75 is a hollow linear member having a through hole 75a inside, and is such as a pipe made of metal such as stainless steel or a tube made by plastic extrusion molding. The method of joining the connecting members 71 to 73 and the hollow member 75 is the same as the method of joining the connecting member 21 and the linear member 20 in Example 1, and a detailed explanation is omitted here.

[0121] Each linear member 70 is fixed to the joints 71a to 73a via the hollow members 75. As shown in Figure 14(b), the fixed portion 77a of the linear member 77 is inserted into the through hole 75a of the hollow member 75, and the linear member 77 and the hollow member 75 are joined by methods such as adhesive bonding, crimping, or welding. The hollow member 75 can also be considered part of the fixing portion of the connecting members 71 to 73 to which the linear member 77 is fixed.

[0122] With the above configuration, it is possible to transmit a thrust in the z-axis direction to the linear member 77 by pushing and pulling the force receiving portions 71b to 73b provided on the connecting members 71 to 73 in the z-axis direction.

[0123] <Prevention of buckling of linear members> Next, we will describe the buckling prevention section 55 that prevents buckling of the linear member 77. As shown in Figure 11(c), the curved body manipulator 50 has a buckling prevention section 55 to prevent buckling of the linear member 77. The configuration of the buckling prevention section 55 will be explained using Figures 20, 21, 22, and 23.

[0124] Figure 20(a) is a schematic perspective view showing the configuration of the buckling prevention section 55. Figure 20(b) is an enlarged view of the dashed area J showing the configuration of the buckling prevention section 55, and is an enlarged view of a part of the interior of the buckling prevention section 55. Figure 21(a) is a cross-sectional view of the curved body manipulator 50, and is an enlarged cross-sectional view of the dashed area G in Figure 13, and Figure 21(b) is an enlarged view of the dashed area K. Figure 22 is a cross-sectional view of the curved body manipulator 50, and is a schematic cross-sectional view when the curved body manipulator 50 is cut at the MM cross section and the buckling prevention section 55 is viewed from the negative z-axis direction to the positive z-axis direction. Figure 22(b) is an enlarged view of the dashed area N.

[0125] The buckling prevention section 55 has an inner member 79, an outer member 80, nine hollow members 75, and an elastic member 76. Each of the nine hollow members 75 and elastic member 76 corresponds to each of the nine linear members 77.

[0126] Using Figures 20(a) and (b), the relative positional relationship between the hollow member 75, the elastic member 76, and the connecting member 71 with respect to the linear member 77 will be explained, with the drive shaft 1a as an example. The coil spring-shaped elastic member 76 is wrapped around a portion of the linear member 77 that extends in the positive z-axis direction from inside the hollow member 75. The hollow member 75 and the elastic member 76 form a buckling prevention region 78.

[0127] The outer diameter of the elastic member 76 is preferably less than or equal to the outer diameter of the hollow member 75, and more preferably larger than the holes 70a to 70i of the tubular member 70. The inner diameter of the elastic member 76 is preferably greater than or equal to the outer diameter of the linear member 77.

[0128] The elastic member 76 is positioned between the hollow member 75 and the tubular member 70. Preferably, the elastic member 76 is a compression coil spring. Preferably, the natural length of the elastic member 76 is set such that when the curved portion 53 is straight along the z-axis, the end of the elastic member 76 in the positive z-axis direction contacts the end of the tubular member 70 of the curved body 210, and the end in the negative z-axis direction contacts the end of the hollow member 75. Furthermore, it is preferable that contact between the elastic member 76 and the tubular member 70, and between the elastic member 76 and the hollow member 75 are maintained when the connecting members 71, 72, and 73 move along the direction of movement.

[0129] Next, the z-axis direction guide mechanism of the buckling prevention region 78 will be described. Figure 23(a) is a schematic perspective view of the inner member 79, and (b) is a schematic front view of the inner member 79.

[0130] The inner member 79 has a hollow shape with a through hole 79a inside, and nine U-shaped grooves 79b are provided around the through hole 79a.

[0131] As shown in Figure 21(b), the buckling prevention region 78 is movable in the z-axis direction inside the groove 79b. As shown in Figure 22(b), a cylindrical outer member 80 is provided on the outside of the buckling prevention region 78, which suppresses radial displacement of the buckling prevention region 78.

[0132] Furthermore, the inner member 79 is positioned to be in contact with the tubular member 70, and the inner skin 56 is positioned to extend from inside the tubular member 70 in the negative z-axis direction. In addition, a part of the tubular member 70 is fitted into the outer member 80, and the cylindrical inner wall of the outer casing member 51 holds the side surface of the outer member 80, thereby supporting the buckling prevention portion 55 on the outer casing member 51.

[0133] With the above configuration, the gap between the linear member 77 and the groove 79b in the radial direction is filled by the elastic member 76. Furthermore, by covering the linear member 77 with the elastic member 76, buckling of the linear member 77 can be suppressed even when it is subjected to a compressive load. Even if the linear member 77 does buckle, the deflection due to buckling can be expected to be minimized.

[0134] Furthermore, similar to Example 1, the intermediate portion 77b of the linear member 77 is straight between the curved body 210 and the connecting members 71, 72, and 73.

[0135] Next, the method for inserting tools in this embodiment will be described. The curved body manipulator 50 according to this embodiment allows various tools to be inserted toward the curved portion 53, similar to the first embodiment.

[0136] As shown in Figures 13 and 15, various tools are inserted toward the curved section 53 using an insertion opening 57a provided on the side of the central member 57. As shown in Figure 15(b), the insertion opening 57a has a hollow shape with a through hole 57b. A curved pipe 58 is attached to the through hole 57b. A straight pipe 59 is inserted into the curved pipe 58. The curved pipe 58 is elastically deformed by the straight pipe 59, forming a seal structure between the curved pipe 58 and the straight pipe 59, ensuring internal airtightness. In this embodiment, the curved pipe 58 is made of a rubber tube or the like, and the straight pipe 59 is made of a stainless steel pipe or the like.

[0137] One end of the straight pipe 59 is fixed to the support portion 57e, and as shown in Figure 22(b), the other end is fitted inside the inner member 79 in a portion of the z-axis direction. The inner member 79 is elastically deformed by the straight pipe 59, forming a seal structure between the inner member 79 and the straight pipe 59, thereby ensuring internal airtightness.

[0138] On the other hand, as shown in Figure 21(b), by arranging the inner member 79 in contact with the end face of the tubular member 70 and covering the sides of the tubular member 70 and the inner member 79 with the outer member 80, it is possible to ensure airtightness between the tubular member 70 and the inner member 79.

[0139] With the above configuration, a highly airtight, hollow path can be secured from the curved pipe 58 provided in the insertion port 57a through the straight pipe 59 to the endothelium 56. Using this path, a small camera, forceps, biopsy tools, etc., can be inserted, as in Example 1, to observe and treat objects near the tip of the curved section 53. In addition, by inserting an irrigation suction tube and spraying or sucking liquid through the irrigation suction tube from the tip of the curved section 53, it is possible to clean objects near the tip of the curved section 53 or administer drugs.

[0140] As described above, in this embodiment, as in Embodiment 1, it is possible to efficiently transmit thrust to the linear members 77 arranged in a confined space. In this embodiment, by using nine drive shafts and providing six degrees of freedom to the curved section 53, it is possible to perform more dexterous movements compared to Embodiment 1. Therefore, for example, when the curved body manipulator 50 is used as a neuroendoscope for neurosurgical procedures, it is assumed that the diameter of the outer skin 52 is about 4 mm, the diameter of the inner skin 56 is about 2 mm, and the radius r on which the linear members 77 are arranged is about r = 1.5 mm. By transmitting thrust to multiple linear members 77 arranged in such a confined space using connecting members 71 to 73 guided by the central member 57, the force receiving sections 71b to 73b for transmitting force can be arranged on a circle with a radius sufficiently larger than the radius r.

[0141] Furthermore, according to this embodiment, adjacent connecting members 72 and 73 in the circumferential direction around the central axis CA have bent portions 72f and 73f. This allows for securing a path between the connecting members 72 and 73 for inserting and removing tools, and for securing space to install the insertion opening 57a.

[0142] In this embodiment, in order to suppress buckling of the linear member 77, an elastic member 76 covering the linear member 77 is placed between the joints 71a to 73a and the tubular member 70 of the curved body 210. The natural length of the elastic member 76 was set such that the elastic member 76 is compressed when the connecting members 71 to 73 are at their furthest position from the curved body 210 in the z-axis direction, but is not limited to this. The natural length of the elastic member 76 may be set such that the length of the elastic member 76 is the same as the natural length when the connecting members 71 to 73 are at their furthest position from the curved body 210 in the z-axis direction. In addition, a gap may be formed between the elastic member 76 and the hollow member 75, or between the elastic member 76 and the tubular member 70 of the curved body 210.

[0143] Furthermore, it is preferable to set the elastic modulus of the elastic member 76 to be sufficiently low so that the restoring force of the elastic member 76 does not cause displacement of each drive shaft 1a-1c, 2a-2c, and 3a-3c. To suppress the displacement of each drive shaft 1a-1c, 2a-2c, and 3a-3c, the frictional force between the connecting members 71-73 and the groove 57c may be used. The frictional force can be adjusted by the size of the gap between the connecting members 71-73 and the groove 57c, the combination of materials of both, etc. In this way, by compressing and arranging the elastic member 76, the state in which the linear member 70 is covered by the elastic member 76 is maintained even when transitioning from a state in which the drive shafts 1a-1c, 2a-2c, and 3a-3c are pulled in the negative direction of the z axis to a state in which they are pushed in the positive direction. Therefore, buckling of the linear member 77 can be prevented.

[0144] In this embodiment, the first section 61 is capable of two degrees of freedom of movement (bending and pivoting) in response to three degrees of freedom of input using three drive shafts 1a to 1c. Similarly, the second section 62 is capable of two degrees of freedom of movement (bending and pivoting) in response to three degrees of freedom of input using three drive shafts 2a to 2c, and the third section 63 is capable of two degrees of freedom of movement (bending and pivoting) in response to three degrees of freedom of input using three drive shafts 3a to 3c. In other words, the curved body manipulator 50 according to this embodiment is configured to be capable of six degrees of freedom of movement in response to nine degrees of freedom of input.

[0145] In contrast, similar to Example 1, the inner skin 56 and outer skin 52 may be formed from an expandable material, and each section 1 to 3 may be expandable and contractible in the z-axis direction by pushing and pulling each drive shaft 1a to 1c, 2a to 2c, and 3a to 3c in the same direction. In other words, it is possible to create a curved body manipulator that can perform a total of 9 degrees of freedom of motion in response to 9 degrees of freedom of input.

[0146] [Example 3] Example 3 will be described using Figures 24 and 25. Figure 24 is a schematic perspective view of a curved body robot (continuous body robot) 101 incorporating a curved body manipulator (continuous body manipulator) 100.

[0147] The curved body manipulator 100 includes a driven curved portion 104 which is an extension of the driven curved portion 54 of the curved body manipulator 50 described in Embodiment 2 in the longitudinal direction (z-axis direction), and a curved portion 53 adjacent to the driven curved portion 104.

[0148] In this embodiment, the curved body manipulator 100 differs from the curved body manipulator 50 of embodiment 2 in the lengths of the driven bending portion 54 and the driven bending portion 104. Also, the linear member in this embodiment differs in length from the linear member 77 in embodiment 2.

[0149] Furthermore, the driven bending portion 104 can use a tubular member that has the same cross-sectional shape as the tubular member 70 in Embodiment 2, but is longer than the tubular member 70. The tubular member may be a single component, or a single tubular member may be formed by joining multiple tubular members with different bending rigidities. In this case, it is preferable to select a material such that the bending rigidity decreases from the central member 57 toward the bending portion 53.

[0150] As described above, the ratio of the curved portion 53 to the driven curved portion 104 in this embodiment differs from the ratio of the curved portion 53 to the driven curved portion 54 in the curved body manipulator 50 of Embodiment 2, with the driven curved portion 104 being longer than the curved portion 53. In this embodiment, the total length of the curved portion 53 is approximately 60 mm, while the total length of the driven curved portion 104 is approximately 500 mm. Furthermore, it is preferable that the driven curved portion 104 be formed from a flexible thermoplastic elastomer or the like.

[0151] The curved body robot 101 is equipped with a curved body manipulator 100 and an actuator unit (drive unit) 90 having a drive source for pushing and pulling drive shafts 1a-1c, 2a-2c, and 3a-3c. The curved body manipulator 100 is detachably mounted to the actuator unit 90.

[0152] The actuator unit 90 has a plurality of drive units 901a, 901b, 901c, 902a, 902b, 902c, 903a, 903b, and 903c. The drive units 901a, 901b, and 901c are detachably connected to the force receiving portions 71b of the drive shafts 1a to 1c, respectively, and are configured to move the connecting member 71.

[0153] The drive units 902a and 902c are detachably connected to the force-receiving portions 71b of the drive shafts 2a and 2c, respectively, and are configured to move the connecting member 71. The drive unit 902b is detachably connected to the force-receiving portion 73b of the drive shaft 2b, and is configured to move the connecting member 73.

[0154] The drive units 903a and 903c are detachably connected to the force-receiving portions 71b of the drive shafts 3a and 3c, respectively, and are configured to move the connecting member 71. The drive unit 903b is detachably connected to the force-receiving portion 72b of the drive shaft 3b, and is configured to move the connecting member 72.

[0155] The actuator unit 90 is formed by arranging the drive units 901a, 901b, 901c, 902a, 902b, 902c, 903a, 903b, and 903c radially around the central axis CA.

[0156] Next, the internal structure of the actuator unit 90 will be explained using Figure 25. Figure 25 is a diagram illustrating the drive device 901a for driving the drive shaft 1a.

[0157] Since the drive units 901a, 901b, 901c, 902a, 902b, 902c, 903a, 903b, and 903c have the same configuration, drive unit 901a will be described as a representative example.

[0158] The drive unit 901a has an electromagnetic motor 91. The electromagnetic motor 91 is connected via a coupling 92 to a converter 94 supported by two sets of bearings 93, which rotates the converter 94. The converter 94 converts rotational motion around the z-axis into linear motion in the z-axis direction.

[0159] A ball screw or a lead screw can be used as the conversion part 94. Specifically, a helical groove is formed in the conversion part 94 and engages with the tractor 97. On the other hand, the drive device 901 has a linear guide 95 which includes a rail 95a fixed to the housing 96 and a slider 95b that can move along the rail 95. The tractor 97 is connected to the linear guide 95 via the slider 95b and is movable in the z-axis direction. The upper end of the tractor 97 is engaged with the force receiving part 71b of the connecting member 71 by a pin 98. With the above configuration, the connecting member 71 can be pushed and pulled in the z-axis direction by rotating the electromagnetic motor 91.

[0160] According to this embodiment, the attitude of the curved section 53 can be easily set by the actuator unit 90 that drives each of the drive shafts 1a-1c, 2a-2c, and 3a-3c.

[0161] Furthermore, because the driven bending section 104 is set to be longer than the bending section 53, the bending body manipulator 100 can, for example, be used as a bronchoscope. Having a multi-degree-of-freedom bending section 53 allows the bending body manipulator 100 to be inserted through the mouth and selectively advance through the branching of the bronchi. As a result, it becomes possible to perform camera observation, irrigation using an irrigation suction tube, biopsy, and minimally invasive ablation treatment in target areas deep within the lungs.

[0162] In this embodiment, an example using a rotary electromagnetic motor and a conversion unit is shown, but a mechanism that directly pushes and pulls the connecting members 71-73 using a linear actuator can also be easily applied.

[0163] The embodiments described above can be combined as needed. Furthermore, the curved body manipulators and curved body robots shown in each embodiment can be used as medical devices to be inserted into a patient's body. [Explanation of Symbols]

[0164] 10, 50, 100 Curved Body Manipulator 110,210 curved body 13, 53 Curved section 16a~16c, 1a~1c, 2a~2c, 3a~3c drive shaft 20, 77 Linear members 21, 71-73 Connecting members 101 Curved Body Robot

Claims

1. A curved body including a curved section, Guide member and A plurality of input sections connected to the curved section, each having (i) a linear member connected to the curved section, extending along the extension direction, and configured to curve the curved section when moved along the extension direction, and (ii) a fixing section to which the linear member is fixed, and a force receiving section, and being movable along the direction of movement, with respect to the direction perpendicular to the extension direction, A plurality of input units having a connecting member positioned further from the linear member than the fixed portion, It has, When the force receiving portion receives force, the connecting member is guided by the guide member and moves along the direction of movement so that the linear member moves along the extension direction. The fixing portion is arranged such that the linear member extends in a straight line between the curved body and the fixing portion. The curved body manipulator is characterized in that the guide member has a groove into which the connecting member fits.

2. The curved body manipulator according to Claim 1, further comprising a cover member that covers the groove, wherein the cover member is configured to restrict the movement of the connecting member.

3. A curved body including a curved portion and having multiple holes, Guide member and A plurality of input sections connected to the curved section, each having (i) a linear member connected to the curved section, extending along the extension direction, and configured to curve the curved section when moved along the extension direction, and (ii) a fixing section to which the linear member is fixed, and a force receiving section, and being movable along the direction of movement, with respect to the direction perpendicular to the extension direction, A plurality of input units having a connecting member positioned further from the linear member than the fixed portion, It has, The linear member has a portion that is inserted into one of the plurality of holes and fixed to the fixing portion, When the force receiving portion receives force, the connecting member is guided by the guide member and moves along the direction of movement so that the linear member moves along the extension direction. A curved body manipulator characterized in that, when viewed along the aforementioned direction of movement, the fixed portion and one of the plurality of holes at least partially overlap.

4. The curved body manipulator according to claim 3, characterized in that the guide member has a groove into which the connecting member fits.

5. The curved body manipulator according to claim 4, further comprising a cover member that covers the groove, wherein the cover member is configured to restrict the movement of the connecting member.

6. The curved body manipulator according to any one of claims 1 to 5, characterized in that the guide member restricts the movement of the connecting member in a direction intersecting the direction of movement.

7. The curved body manipulator according to any one of claims 1 to 6, characterized in that the connecting member is slidably supported on the guide member.

8. The curved body manipulator according to any one of claims 1 to 7, characterized in that the force receiving portion is positioned offset from the fixed portion in the direction of movement.

9. The curved body manipulator according to any one of claims 1 to 8, characterized in that the linear member is fixed to the fixing part via a hollow member.

10. The curved body manipulator according to any one of claims 1 to 9, characterized in that the connecting member includes a plate portion having a plate shape.

11. The curved body manipulator according to claim 10, characterized in that a part of the plate portion is bent.

12. The connecting member is arranged such that the surface perpendicular to the thickness direction of the plate portion is aligned with the direction of movement. The curved body manipulator according to claim 10 or 11, characterized in that the guide member contacts and guides the surface.

13. The curved body manipulator according to any one of claims 10 to 12, characterized in that the fixing part is located at the end of the plate portion.

14. The curved body manipulator according to any one of claims 1 to 13, characterized in that the fixing portion is positioned closer to the central axis than the force receiving portion in a direction perpendicular to the central axis of the curved body.

15. The curved body manipulator according to any one of claims 1 to 14, characterized in that the connecting member has an L-shape.

16. The curved body manipulator according to any one of claims 1 to 15, characterized in that the connecting member is provided with an inclined portion.

17. The curved body manipulator according to any one of claims 1 to 16, characterized in that it has an elastic member disposed between the fixed portion and the curved body and covering the linear member.

18. A curved body manipulator according to any one of claims 1 to 17, It has multiple drive units, A curved robot characterized in that each of the plurality of drive devices is connected to the force receiving portion and configured to move the connecting member.

19. The drive unit has the aforementioned multiple drive devices, The curved body robot according to claim 18, characterized in that the curved body manipulator is detachably mounted to the drive unit.

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