Maneuverable instrument for endoscopic or invasive applications

Abstract

The cylindrical instrument has a first tube (1601; 1619), a second tube (1620) surrounding the first tube (1601; 1619), and a third tube (1602; 1621) surrounding the second tube (1620). The instrument has a deflectable tip section (1613), a steering section (1618), a flexible body section (1615) between the tip section (1613) and the steering section (1618), a length compensation section (1617), and one or more steering wires (16(i)) extending from the steering section (1618) to the tip section (1613), such that the tip section (1613) can be deflected by moving the one or more steering wires (16(i)) longitudinally of the cylindrical instrument. The cylindrical instrument has a Bowden cable arrangement for each steering wire (16(i)) inside the length compensating section (1617), and each Bowden cable arrangement has the steering wire (16(i)) surrounded by a steering wire guide portion. The steering wire (16(i)) and steering wire guide portion are part of the first tube (1619), the second tube (1620), or the third tube (1621).

Description

Technical Field

[0001]

[0001] The present invention relates to steerable instruments for endoscopic and / or invasive type applications such as surgery. The steerable instruments according to the present invention can be used for both medical and non-medical applications. Examples of non-medical applications include inspection and / or repair of mechanical and / or electronic hardware in locations that are difficult to access. Accordingly, the terms used in the following description such as endoscopic applications or invasive instruments must be interpreted broadly.

Background Art

[0002]

[0002] The transition from surgical interventions that require large incisions to expose the target region to minimally invasive surgical interventions, that is, surgical interventions that only require natural or small incisions to establish access to the target region, is a well-known and ongoing process. In performing minimally invasive surgical interventions, an operator such as a physician requires an access device arranged to introduce and guide an invasive instrument into the body of a human or animal through an access port of the body. In order to reduce scar tissue formation and pain to a human or animal patient, the access port is preferably provided by a single small incision in the skin and the underlying tissue. In some applications, a natural body cavity may be used as the entry point. Furthermore, the access device preferably allows the operator to control one or more degrees of freedom provided by the invasive instrument. In this way, the operator can perform the required actions at the target region within the human or animal body in an ergonomic and precise manner while reducing the risk of collision of the instruments being used.

[0003]

[0003] Surgical invasive instruments and endoscopes are known in the art. Both invasive instruments and endoscopes may be equipped with maneuverable tubes to enhance their navigation and maneuverability. Such a maneuverable tube may comprise a proximal end including at least one flexible zone, a distal end including at least one flexible zone, and an intermediate section, and the maneuverable tube further comprises a maneuvering arrangement adapted to make the deflection of at least a portion of the proximal end relative to the intermediate section an associated deflection of at least a portion of the distal end. Alternatively, the distal flexible zone may be maneuvered by a robotic instrument located at the proximal end of the maneuverable instrument.

[0004]

[0004] The maneuverable invasive instrument may have a handle located at the proximal end of the maneuverable tube for maneuvering the tube and / or operating a tool located at the distal end of the maneuverable tube. Such tools may be, for example, a camera, a manual operator such as scissors, forceps, or an operator using an energy source such as an electrical, ultrasonic, or optical energy source.

[0005]

[0005] Furthermore, such a maneuverable tube may comprise several cylindrical elements arranged coaxially, including an outer cylindrical element, an inner cylindrical element, and one or more intermediate cylindrical elements depending on the number of flexible zones in the proximal and distal ends of the tube and the desired implementation of the maneuvering members of the maneuvering arrangement, i.e., all maneuvering members can be located within a single intermediate cylindrical element, or the maneuvering members may be divided into different sets, each set of maneuvering members located at least partially within different or the same intermediate cylindrical element. In most prior art devices, the maneuvering arrangement comprises, for example, a conventional maneuvering cable having a diameter of 1 mm or less as a maneuvering member, and the maneuvering cable is located between the relevant flexible zones at the proximal and distal ends of the tube. Other maneuvering units located at the proximal end, such as a ball-shaped maneuvering unit or a robot-driven maneuvering unit, may be applied instead.

[0006]

[0006] However, since control cables have many well-known drawbacks, in some applications it may be desirable to avoid them and implement the control member by one or more sets of control wires forming an integral part of one or more intermediate cylindrical elements. Each of the intermediate cylindrical elements containing the control wires may be manufactured by using appropriate material addition techniques such as injection molding or plating, or by starting from a tube and then using appropriate material removal techniques such as laser cutting, photochemical etching, deep pressing, conventional chipping techniques such as drilling or milling, or a high-pressure water jet cutting system. The control wires thus manufactured may then be implemented as longitudinal strips resulting from the tube material and used as tension / extruded wires. Among the material removal techniques mentioned above, laser cutting is particularly advantageous because it allows for very precise and clean material removal under reasonable economic conditions.

[0007]

[0007] The inner and outer cylindrical elements may also be manufactured from tubes. These tubes must be flexible where the distal end of the instrument, and possibly the proximal end as well, is bendable. The inner and outer cylindrical elements must also be flexible where the instrument must be flexible elsewhere. This can be implemented by providing hinges on the inner and outer cylindrical elements at these flexible locations. Such hinges may result from (laser) cutting a predetermined pattern into the tube. Many different patterns are known from the prior art. The choice of pattern to use is not limited to but depends on the design requirements at the relevant location, including the required bending angle, bending flexibility, longitudinal stiffness, and radial stiffness.

[0008]

[0008] Further details relating to the design and fabrication of the aforementioned controllable tube and its control arrangement are described, for example, in the applicant's International Publication No. 2009 / 112060, International Publication No. 2009 / 127236, U.S. Patent Application No. 13 / 160,949, and U.S. Patent Application No. 13 / 548,935, all of which are incorporated herein by reference in their entirety.

[0009]

[0009] As is known from, for example, flexible endoscopic instruments with maneuverable tips, flexible invasive maneuverable instruments may have performance deficiencies with respect to the control of the insertable tip. When such a flexible instrument is inserted into the body through a curved channel, i.e., either an endoscope or a natural body cavity, the bending of the instrument causes displacement of the longitudinal tip maneuvering element. In conventionally constructed instruments, the maneuvering element, such as a wire, is fixed proximal to a maneuvering device such as a handle and distal to the maneuverable tip, so that movement of the maneuvering wire results in deflection of the maneuvering device and / or deflection of the maneuverable tip. This results in the tip potentially becoming uncontrollably deflected during advancement when the instrument is advanced through a narrow, curved channel and the maneuvering device is held in a fixed position, which could lead to problems such as, for example, the tip becoming immobile within a narrow endoscopic working channel, or this could potentially damage tissue in a natural body cavity of soft tissue, such as the lungs, bronchi, or esophagus.

[0010]

[0010] Another problem is that when the instrument passes through the entry channel and the tip of the instrument reaches the target surgical site, the deflection of the tip no longer matches the deflection of the control device. Therefore, the neutral position of the control device does not correspond to the neutral position of the controllable tip. This offset has a detrimental effect on the user's visual-hand coordination.

[0011]

[0011] Another problem with flexible, maneuverable instruments is that when the tip is manipulated by the maneuvering element, the entire body behaves mechanically like a maneuverable tip, and therefore the body is also manipulated by the maneuvering element. The deflection ratio between the body and the tip depends only on the bending stiffness of the body and the tip. The greater the stiffness of the body relative to the stiffness of the tip, the more the tip is maneuvered. In fact, although the tip is more flexible than the body, there is still a tendency for body deflection to occur as a result of tip manipulation, and this body deflection further generates lateral forces on the surrounding channel, which tends to keep the instrument body at a particular curvature. This is an extremely undesirable instrument behavior, as these lateral forces may damage the surrounding tissue if the surrounding channel is made of soft body tissue. Also, movement of the body may interfere with the positioning of the maneuverable tip at the target site, making accurate and predictable tip manipulation more difficult.

[0012]

[0012] Addressing the problem of undesirable tip manipulation due to bending of the instrument body, a partial solution to this problem is described in International Publication No. 2014 / 011049. This solution describes an instrument in which the steering wires can be detached from the steering device, and the ends of these steering wires, and therefore the instrument tip, can move freely as the instrument is advanced through a curved entrance path. Once the instrument tip has passed through the entrance channel and reached the target surgical site, the steering wires are reconnected to the steering device, and the instrument tip can then be manipulated. A drawback of this solution is that the instrument is mechanically more complex and requires more components to construct. Another drawback is that the operator must follow certain procedures in order to pass through the curved entrance channel, which may be prone to errors or may be forgotten. Yet another drawback is that the problem of body manipulation (lateral forces) is still not addressed.

[0013]

[0013] Common to the solutions of the prior art is that they are constructed from specially fabricated tubing, coils, and machined components, and the assembly of such fixtures is usually a time-consuming and difficult process. In addition, tolerances of separate components are introduced during assembly, which can lead to a wide range of fixture performance, for example, and often require individual calibration of each fixture. [Overview of the project]

[0014]

[0014] An object of the present invention is to provide a maneuverable instrument for endoscopic and / or invasive type applications that solves or at least reduces at least one of the problems mentioned above.

[0015]

[0015] To achieve this objective, independent aspects of the present invention are defined in independent claims, while dependent claims relate to advantageous embodiments.

[0016]

[0016] Some embodiments feature a Bowden cable arrangement.

[0017]

[0017] In this application, the terms “proximal” and “distal” are defined with respect to the operator, for example, a robot or physician operating an instrument or endoscope. For example, the proximal end is interpreted as the part located near the robot or physician, and the distal end is interpreted as the part located at a distance from the robot or physician, i.e., within the surgical area.

[0018]

[0018] In many embodiments, the present invention provides a device that has performance equivalent to or improved upon conventional solutions, but is constructed with a significantly reduced number of separate components and a significantly reduced assembly effort. All necessary elements for structuring a maneuverable device, including a Bowden cable structure, may be manufactured integrally from several tubes, mostly in a pre-assembled state. The only remaining assembly step consists of sliding the tubes inward and fitting their tubing together where required. The pre-assembled components may be fabricated within the tube walls by a material deposition process such as 3D printing or plating technology. Preferably, the pre-assembled components may be fabricated by a material removal process from solid-walled metal or plastic tubes (such as stainless steel, cobalt-chromium alloy, or superelastic alloys such as Nitinol). Material removal processes that may be used include, for example, conventional chipping processes, water jet cutting, etching, and preferably laser cutting processes.

[0019]

[0019] Accordingly, these embodiments of the present invention enable a significant reduction in the manufacturing cost of such instruments, and therefore the cost of the interventions in which these instruments are used. It is also becoming commercially feasible to use these instruments only once and then discard them. This enhances the safety of the intervention, as new instruments may be used instead of used, re-sterilized instruments, which are known to have a 10% risk of post-procedure complications due to patient contamination or infection by used instruments that have not been properly cleaned or re-sterilized.

[0020]

[0020] A further advantage of such a device is that by using this integrated method of producing the members in a pre-assembled state, these members always fit with each other, and minimal play between the members can be achieved. This is particularly true when a laser cutting process is used. The minimum achievable play between two integrally manufactured members can be as small as 0.01 mm, which is as small as the width of the laser beam used. Usually, a play of 0.01 to 0.05 mm can be easily obtained. Therefore, the integral fabrication of the members according to the present invention is accurate with respect to the fit of the members and the play therebetween, thus ensuring improved accuracy and repeatability of the functional performance of the device.

[0021]

[0021] Further features and advantages of the present invention will become apparent from the description of the present invention according to non-limiting and non-exclusive embodiments. These embodiments shall not be construed as limiting the scope of protection. Those skilled in the art will recognize that other alternatives and equivalent embodiments of the present invention can be conceived and put into practice without departing from the scope of the present invention. Embodiments of the present invention are described with reference to the figures of the accompanying drawings, in which like or identical reference numerals indicate like, identical or corresponding members. The present invention provides, for example, the following: (Item 1) A cylindrical instrument comprising at least a first tube (1601;1619), a second tube (1620) surrounding the first tube (1601;1619), and a third tube (1602;1621) surrounding the second tube (1620), wherein the cylindrical instrument comprises at least one deflectable tip section (1613), a steering section (1618), and the tip section (1613) and the steering section (1 The device comprises a flexible body section (1615) between 618) and a length compensation section (1617), and one or more control wires (16(i)) extending from the control section (1618) to the tip section (1613), wherein the tip section (1613) can deflect one or more control wires (16(i)) by moving the one or more control wires (16(i)) in the longitudinal direction of the cylindrical device, A cylindrical device wherein the length compensation section (1617) comprises a first portion of a control wire (16(i)) at least partially surrounded by a control wire guide portion, and both each control wire (16(i)) and the associated control wire guide portion are part of at least one of the first tube (1619), the second tube (1620), or the third tube (1621), and each first portion of the control wire (16(i)) and the associated control wire guide portion is configured as a length compensation element having a curved configuration configured to deform to absorb the change in length of the second portion of the control wire (16(i)) inside the flexible body section (1615) due to the bending of the flexible body section (1615). (Item 2) The cylindrical instrument according to item 1, wherein the curved configuration is at least one of the following: extending radially outward from the central axis (1622), extending radially inward toward the central axis (1622), extending tangentially with respect to the central axis (1622), or being helical around the central axis of the cylindrical instrument. (Item 3) The cylindrical device according to item 1 or 2, wherein the control wire guide portion comprises at least one longitudinal guide element length compensation portion (1620a(2,i), 1620b(2,i)) aligned with the first portion of each control wire (16(i)), and the at least one longitudinal guide element length compensation portion (1620a(2,i), 1620b(2,i)) is the same portion of at least one of the first tube (1619), the second tube (1620), or the third tube (1621), of which the control wire (16(i)) is a portion. (Item 4) The cylindrical device according to item 3, wherein the at least one longitudinal guide element length compensation portion (1620a(2,i), 1620b(2,i)) comprises two longitudinal guide element length compensation portions (1620a(2,i), 1620b(2,i)) along different sides of the first portion of each steering wire (16(i)). (Item 5) The cylindrical instrument according to any one of items 1 to 4, wherein the length compensation section (1617) comprises an inner control wire guide portion (1619(2,i)) which is part of the first tube (1619) and an outer control wire guide portion (1621(2,i)) which is part of the third tube (1621). (Item 6) The cylindrical device according to item 5, wherein in the length compensation section (1617), the control wire guide portion is located tangentially adjacent to the control wire (16(i)), and the control wire guide portion comprises one or more radially oriented lips (1623) attached to at least one of the inner control wire guide portion (1619(2,i)) or the outer control wire guide portion (1621(2,i)). (Item 7) The cylindrical device according to item 5, wherein the length compensation section (1617) comprises one or more island portions (1625(j)) slidably disposed within the at least one control wire (16(i)) to limit the tangential movement of the at least one control wire (16(i)). (Item 8) A cylindrical device according to any one of items 1 to 7, comprising a square element (1645) having a first bar (1645(1)) and a second bar (1645(2)) both extending in a first direction, and a third bar (1645(3)) and a fourth bar (1645(4)) both extending in a second direction perpendicular to the first direction, wherein the first and second bars (1645(1), 1645(2)) are slidably connected to the vertices of a pair of opposing sets of a control wire and associated control wire guide portions within the length compensation section (1617), and the third and fourth bars (1645(3), 1645(4)) are slidably connected to the vertices of another pair of opposing sets of a control wire and associated control wire guide portions within the length compensation section (1617). (Item 9) A cylindrical instrument according to any one of items 1 to 8, wherein a portion of one control wire (16(i)) is located in one of the first, second, and third tubes (1619, 1620, 1621) in at least two different sections from the at least one deflectable tip section (1613), the control section (1618), the flexible body section (1615), and the length compensation section (1617). (Item 10) A cylindrical instrument comprising at least one deflectable tip section (1301; 1613), a steering section (1618), a flexible body section (1615) between the tip section (1613) and the steering section (1618), a length compensation section (1617), and one or more steering wires (16(i), 1309(i)) extending from the steering section (1618) to the tip section (1613), wherein the tip section (1613) can be deflected by moving the one or more steering wires (16(i), 1309(i)) in the longitudinal direction of the longitudinal instrument, The cylindrical device has a Bowden cable configuration for each control wire (16(i), 1309(i)) inside the flexible body section (1615) and the length compensation section (1617), each Bowden cable configuration comprising at least one control wire (16(i), 1309(i)) and a control wire guide, each control wire guide having a distal control wire guide end attached to the cylindrical device at the transition between the tip section (1301; 1613) and the flexible body section (1303; 1615), and the length compensation A cylindrical instrument having a proximal control wire guide end extending inside a section (1617), the cylindrical instrument comprising one or more sensors (1663(i)), each configured to sense the longitudinal movement of one of the proximal control wire guide ends, and one or more actuators (1665(i)), each configured to control the longitudinal movement of one control wire (16(i), 1309(i)) to compensate for the longitudinal movement of the associated proximal control wire guide end due to bending of the flexible body sections (1303; 1615). (Item 11) The cylindrical instrument according to item 10, wherein each sensor (1663(i)) is configured to transmit a sensor signal to a processor, the processor being configured to generate an actuation signal for each actuator (1665(i)) in response to the associated sensor signal, such that each actuator (1665(i)) performs a compensated longitudinal movement of the associated control wire (16(i), 1309(i)). (Item 12) The cylindrical instrument according to item 10, wherein each sensor is mechanically coupled to the associated proximal control wire guide end of each actuator (1665(i)) and moves with the proximal control wire guide end during bending of the body section, and is implemented as a mechanical coupling configured to keep the control wire (16(i), 1309(i)) a constant distance extending proximal outside the associated control wire guide unless an actuation signal is received by the actuator (1665(i)). (Item 13) A cylindrical instrument according to any one of items 10 to 12, comprising a braking device (1671(i)) for each proximal end of the control wire guide, each braking device (1671(i)) configured to allow or block longitudinal movement of the respective proximal control wire guide end. (Item 14) A cylindrical instrument comprising at least a first tube (1601;1619), a second tube (1620) surrounding the first tube (1601;1619), and a third tube (1602;1621) surrounding the second tube (1620), The cylindrical device comprises at least one deflectable tip section (1613), a control section (1618), a flexible body section (1615) between the tip section (1613) and the control section (1618), a length compensation section (1617), and one or more control wires (16(i)) extending from the control section (1618) to the tip section (1613), wherein the tip section (1613) can deflect one or more control wires (16(i)) by moving the one or more control wires (16(i)) in the longitudinal direction of the cylindrical device. Each control wire (16(i)) comprises a portion of at least one of the first tube (1619), the second tube (1620), or the third tube (1621). A cylindrical device in which each control wire (16(i)) in the length compensation section (1617) comprises a first portion and a second portion, the first portion comprising a projection (16(i, 9)), and the second portion comprising a recess (16(i, 8)) for receiving the projection, and both the projection (16(i, 9)) and the recess (16(i, 8)) are angled with respect to the tangential direction of the cylindrical device and configured to compensate for changes in the length of one or more control wires (16(i)) within the flexible body section (1615) due to bending of the flexible body section (1615). (Item 15) A cylindrical controllable device comprising: at least one deflectable tip section (1301); a control section (1307); at least one flexible body section (1303) located between the tip section (1301) and the control section (1307); a length compensation section (3200) located between the at least one flexible body section (1303) and the control section (1307); and one or more control wires (16(i)) extending from the control section (1307) to the deflectable tip section (1301), wherein the tip section (1301) can be deflected by moving the one or more control wires (16(i)) in the longitudinal direction of the cylindrical controllable device, The aforementioned cylindrical, operable device is For at least one control wire (16(i)), one or more sensing elements (3201(i)) are provided, each having a first end attached to the at least one flexible section (1307) and a second end extending into the length compensating section (3200), and configured to move longitudinally within the at least one flexible section (1307) by bending of the at least one flexible section (1307), and then move a first slider (3218; 4206(2); 4206(4)) tangentially to the cylindrical controllable device, At least one second slider (3219; 3219a, 3219b; 4208(3); 4208(4)), wherein each second slider (4208(3); 4208(4)) moves tangentially together with one first slider (3218; 4206(2); 4206(4)), but is configured to move longitudinally of the cylindrical maneuverable device independently of the first slider (3218; 4206(2); 4206(4)), Equipped with, A cylindrical controllable device wherein the at least one control wire (16(i)) comprises a first control wire portion (16(i, 1)) and a second control wire portion (16(i, 2)), both of which are connected to the at least one second slider (3219; 3219a; 3219b; 4208(3); 4208(4)) such that the longitudinal distance between the first control wire portion (16(i, 1)) and the second control wire portion (16(i, 2)) is adjusted when the at least one second slider moves in the tangential direction. (Item 16) A method for manufacturing a cylindrical, operable instrument, To provide at least a first tube (4300), Creating a slotted pattern within at least the first tube to generate a first tube portion (4302) and a second tube portion (4304) attached to each other by at least one crushing element (4306), A method comprising releasing the attachment between the first tube portion (4302) and the second tube portion (4304) by subjecting the at least one crushing element (4306) to several fatigue cycles. (Item 17) A method for manufacturing a cylindrical, operable instrument, To provide at least a first tube (4300), Creating a slotted pattern within at least the first tube to generate a first tube portion (4302) and a second tube portion (4304) attached to each other by at least one molten element (4604(1), 4604(2), 4604), A method comprising directing an energy beam, such as a laser beam, at the molten elements (4604(1), 4604(2), 4604) to release the attachment between the first tube portion (4302) and the second tube portion (4304). (Item 18) The method according to item 17, comprising attaching at least one of the first tube portion (4302) or the second tube portion (4304) to a portion of the second tube inside the first tube by a molten portion of the molten element (4606). [Brief explanation of the drawing]

[0022] [Figure 1]

[0022] A schematic cross-sectional view of an invasive instrument assembly having one bendable distal end portion and one proximal end portion, the bending of which of the bendable distal end portion is controlled by a strip cut into the cylindrical element. [Figure 2]

[0023] A schematic overview of the three cylindrical elements from which the device shown in Figure 1 can be manufactured. [Figure 3a]

[0024] Figures 1 and 2 show a portion of the intermediate cylindrical element of the device. [Figure 3b]

[0025] A diagram showing alternative examples of intermediate cylindrical elements in such devices. [Figure 4]

[0026] A diagram showing an exemplary intermediate cylindrical element and an inner cylindrical element inserted within the intermediate cylindrical element. [Figure 5]

[0027] External view of a maneuverable invasive instrument assembly having two maneuverable, bendable distal end portions and two proximal flexible control portions. [Figure 6]

[0028] A magnified view of the distal tip of the instrument shown in Figure 5. [Figure 7]

[0029] A cross-sectional view showing the invasive instrument shown in Figure 5. [Figure 8]

[0030] Figures 5 and 7 illustrate examples of how invasive instruments can bend. [Figure 9] Another diagram showing an example of how the invasive instruments in Figures 5 and 7 can bend. [Figure 10]

[0031] Figures 5-9 illustrate alternative embodiments of the invasive instrument, in which at least a portion of the intermediate section between the distal and proximal ends is also flexible. [Figure 11]

[0032] A schematic diagram illustrating the use of an invasive instrument as an endoscopic surgical instrument, where the intermediate section between the distal and proximal ends is also flexible, allowing the invasive instrument to be inserted into a natural body tube such as the intestine. [Figure 12] Another diagram illustrating a schematic example of using an invasive instrument as an endoscopic surgical instrument, where the intermediate section between the distal and proximal ends is also flexible, allowing the invasive instrument to be inserted into the esophagus. [Figure 13]

[0033] A diagram showing a prior art fixture having a Bowden cable arrangement to compensate for changes in the length of the control wire within the main body section when the main body section bends. [Figure 14] Another diagram shows a prior art fixture having a Bowden cable arrangement to compensate for changes in the length of the control wires within the main body section when the main body section bends. [Figure 15] Another diagram shows a prior art fixture having a Bowden cable arrangement to compensate for changes in the length of the control wires within the main body section when the main body section bends. [Figure 16]

[0034] A diagram showing a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and which extends radially and outward from the central axis of the device. [Figure 17] Another diagram shows a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and the cable extends radially and outward from the central axis of the device. [Figure 18A] Another diagram shows a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and the cable extends radially and outward from the central axis of the device. [Figure 18B] Another diagram shows a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and the cable extends radially and outward from the central axis of the device. [Figure 19] Another diagram shows a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and the cable extends radially and outward from the central axis of the device. [Figure 20]Another diagram shows a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and the cable extends radially and outward from the central axis of the device. [Figure 21A] Another diagram shows a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and the cable extends radially and outward from the central axis of the device. [Figure 21B] Another diagram shows a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and the cable extends radially and outward from the central axis of the device. [Figure 22] Another diagram shows a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and the cable extends radially and outward from the central axis of the device. [Figure 23] Another diagram shows a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and the cable extends radially and outward from the central axis of the device. [Figure 24A] Another diagram shows a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and the cable extends radially and outward from the central axis of the device. [Figure 24B] Another diagram shows a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and the cable extends radially and outward from the central axis of the device. [Figure 25A] Another diagram shows a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and the cable extends radially and outward from the central axis of the device. [Figure 25B] Another diagram shows a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and the cable extends radially and outward from the central axis of the device. [Figure 26A]

[0035] A diagram showing an embodiment in which the Bowden cable arrangement extends in a helical shape within a longitudinal compensation section. [Figure 26B] Another diagram showing an embodiment in which the Bowden cable arrangement extends in a helical shape within the longitudinal compensation section. [Figure 26C] Another diagram showing an embodiment in which the Bowden cable arrangement extends in a helical shape within the longitudinal compensation section. [Figure 26D] Another diagram showing an embodiment in which the Bowden cable arrangement extends in a helical shape within the longitudinal compensation section. [Figure 26E] Another diagram showing an embodiment in which the Bowden cable arrangement extends in a helical shape within the longitudinal compensation section. [Figure 26F] Another diagram showing an embodiment in which the Bowden cable arrangement extends in a helical shape within the longitudinal compensation section. [Figure 27]

[0036] A diagram illustrating a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a single tube, and configured so that length-compensated movement occurs tangentially to the tube. [Figure 28a]

[0037] A diagram illustrating an embodiment in which a portion of the steering wire inside the length compensation section, when manufactured from the tube, is designed to mechanically compensate for changes in the length of the steering wire within the main body section when the main body section bends. [Figure 28b] Another diagram shows an embodiment in which a portion of the steering wire inside the length compensation section, when manufactured from the tube, is designed to mechanically compensate for changes in the length of the steering wire within the body section when the body section bends. [Figure 29] Another diagram shows a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and the cable extends radially and inward from the central axis of the device. [Figure 30]Another diagram shows a device having a Bowden cable arrangement in which both the control wire and the control wire guide element are manufactured as part of a tube surrounding each other, and the cable extends radially and outward from the central axis of the device. [Figure 31a]

[0038] This figure illustrates an embodiment in which a length compensation section is implemented by controlling, via a processor, the longitudinal position of a portion of the steering wire and steering wire guide inside the length compensation section, and also shows reaction force compensation. [Figure 31b] Another figure shows an embodiment in which a length compensation section is implemented by controlling, via a processor, the position of a portion of the steering wire and steering wire guide inside the length compensation section in the longitudinal direction, and also shows reaction force compensation. [Figure 31c] Another figure shows an embodiment in which a length compensation section is implemented by controlling, via a processor, the position of a portion of the steering wire and steering wire guide inside the length compensation section in the longitudinal direction, and also shows reaction force compensation. [Figure 32]

[0039] A diagram showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 33A] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 33B] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 33C] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 34] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 35] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 36] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 37] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 38A]Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 38B] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 39] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 40] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 41A] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 41B] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 42A] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 42B] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 42C] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 42D] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 42E] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 42F] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 42G] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 42H] Another figure showing a further embodiment of a controllable device having a length compensation mechanism. [Figure 43]

[0040] A diagram showing an example of a crushing element between two adjacent parts of a tube. [Figure 44] A diagram showing another example of a crushing element between two adjacent parts of a tube. [Figure 45] A diagram showing another example of a crushing element between two adjacent parts of a tube. [Figure 46]

[0041] A diagram illustrating an example of a molten element between two adjacent parts of a tube. [Figure 47] A diagram showing another example of a molten element between two adjacent parts of a tube. [Figure 48] A diagram showing another example of a molten element between two adjacent parts of a tube. [Figure 49] A diagram showing another example of a molten element between two adjacent parts of a tube. [Modes for carrying out the invention]

[0023]

[0042] For the purposes of this document, the terms cylindrical element and tube may be used interchangeably, i.e., cylindrical element also refers to a physical entity, just as the term tube refers to a physical entity. The present invention is described with reference to a steering wire cut from such a cylindrical element and capable of operating as an extruder and / or pull steering wire to transmit the movement of a steering wire at the proximal end of the instrument to the distal end in order to control the bending of one or more flexible distal end portions. However, in some embodiments, the present invention may also be implemented with steering wires made in a classical manner and not resulting from cutting from a tube. In some embodiments, steering wire guide element portions are also made by cutting them from one or more tubes. These sense or measure differences in the longitudinal length of the instrument body wall by generating a length displacement at one of their ends. [Apparatus to which this invention may be applied]

[0043] Figures 1, 2, 3a, and 3b are known from International Publication No. 2009 / 112060. Since the present invention can be applied to this type of apparatus, these will be described in detail.

[0024]

[0044] Figure 1 shows a longitudinal cross-sectional view of a prior art maneuverable device comprising three coaxially arranged cylindrical elements: an inner cylindrical element 2, an intermediate cylindrical element 3, and an outer cylindrical element 4. Suitable materials used to fabricate the cylindrical elements 2, 3, and 4 include stainless steel, cobalt-chromium, shape memory alloys such as Nitinol®, plastics, polymers, composites, or other materials that can be formed by material removal processes such as laser cutting or EDM. Alternatively, the cylindrical elements may be fabricated by 3D printing processes or other known material deposition processes.

[0025]

[0045] The inner cylindrical element 2 comprises a first rigid end 5 located at the distal end 13 of the device, a first flexible part 6, an intermediate rigid part 7 located at the intermediate part 12 of the device, a second flexible part 8, and a second rigid end 9 located at the proximal end 11 of the device.

[0026]

[0046] The outer cylindrical element 4 also comprises a first rigid end 17, a first flexible end 18, an intermediate rigid end 19, a second flexible end 20, and a second rigid end 21. The lengths of portions 5, 6, 7, 8, and 9 of the cylindrical element 2 and the lengths of portions 17, 18, 19, 20, and 21 of the cylindrical element 4 are preferably substantially the same so that these different portions are aligned longitudinally with one another when the inner cylindrical element 2 is inserted into the outer cylindrical element 4.

[0027]

[0047] The intermediate cylindrical element 3 also has a first rigid end 10 and a second rigid end 15 located between the corresponding rigid ends 5, 17 and 9, 21 of the two other cylindrical elements 2, 4, respectively, when assembled. The intermediate portion 14 of the intermediate cylindrical element 3 comprises one or more separate steering wires 16, which may have different forms and shapes as described below. These are fabricated from the cylindrical element 3 itself and have the form of longitudinal strips. Figure 3a shows three such steering wires 16. After the three cylindrical elements 2, 3, and 4 are assembled, with element 2 inserted into element 3 and the two combined elements 2, 3 inserted into element 4 (any other order is possible), at least the first rigid end 5 of the inner cylindrical element 2, the first rigid end 10 of the intermediate cylindrical element 3, and the first rigid end 17 of the outer cylindrical element 4, located at the distal end of the device, are attached to each other, for example, by adhesive or by one or more laser welding spots. In the embodiments shown in Figures 1 and 2, the second rigid end 9 of the inner cylindrical element 2, the second rigid end 15 of the intermediate cylindrical element 3, and the second rigid end 21 of the outer cylindrical element 4 at the proximal end of the device are also attached to each other, for example, by adhesive or by one or more laser welding spots, so that the three cylindrical elements 2, 3, and 4 form a single integrated unit.

[0028]

[0048] In the embodiment shown in Figure 2, the intermediate portion 14 of the intermediate cylindrical element 3 comprises several control wires 16 having a uniform cross-section, such that the intermediate portion 14 has the overall shape and form shown in Figure 3a of the intermediate cylindrical element 3 in its unwinding state. From Figure 3a, it is also clear that the intermediate portion 14 is formed by several parallel control wires 16, preferably equally spaced, on the circumference of the intermediate cylindrical portion 3. Advantageously, the number of control wires 16 is at least three, but any number greater than this is possible, so that the instrument is fully controllable in any direction. The number of control wires 16 may be, for example, six or eight.

[0029]

[0049] It is observed that the control wires 16 do not need to have a uniform cross-section over their entire length. They may have a variable width along their length, such that adjacent control wires 16 are separated only by small slots resulting from laser cutting within the cylindrical element 3, at one or more locations where possible. These wider portions of the control wires then act as spacers to prevent adjacent control wires 16 from tangentially buckling when pushed out. Alternatively, the spacers may be implemented in other ways.

[0030]

[0050] An embodiment with a spacer is shown in Figure 3b, which shows two adjacent control wires 16 in an unwinded state. In the embodiment shown in Figure 3b, each control wire 16 consists of three portions 61, 62, and 63 located in the same positions as the first flexible portions 6, 18, the intermediate rigid portions 7, 19, and the second flexible portions 8, 20, respectively. In portion 62, which coincides with the intermediate rigid portion, each pair of adjacent control wires 16 are in substantially contact with each other in the tangential direction, so that in practice there is only a narrow slot between them that is sufficient to allow independent movement of each control wire. The slot arises from the manufacturing process, and its width is determined, for example, by the diameter of the laser beam cutting the slot.

[0031]

[0051] In the other two sections 61 and 63, each control wire consists of relatively small flexible sections 64, 65 when viewed circumferentially, resulting in a large gap between each pair of adjacent flexible sections, and each flexible section 64, 65 is provided with several spacers 66 that extend tangentially and almost completely span the gap to the adjacent flexible section 64, 65. These spacers 66 suppress the tendency of the control wire 16 within the flexible section of the instrument to shift tangentially, thereby improving tangential control. The exact shape of these spacers 66 is not so important as long as they do not impair the flexibility of the flexible sections 64 and 65. The spacers 66 may form a single integrated section having the flexible sections 64, 65, which may also result from a suitable laser cutting process.

[0032]

[0052] In the embodiment shown in Figure 3b, the spacers 66 extend in one tangential direction as viewed from the flexible parts 64, 65 to which they are attached. However, it is also possible to have these spacers 66 that start from one flexible part 64, 65 and extend in both circumferential directions. Using this, it is possible to have alternating types of flexible parts 64, 65 as viewed along the tangential direction, in which case the first type has spacers 66 on both sides that extend to the next flexible part, and the second intermediate set of flexible parts 64, 65 does not have spacers 66. Alternatively, it is possible to have flexible parts with cams on both sides, in which case, as viewed along the longitudinal direction of the device, the cams starting from one flexible part alternate with spacers starting from adjacent flexible parts. It is clear that numerous alternatives are available.

[0033]

[0053] The manufacturing of such intermediate components is most conveniently carried out by injection molding or plating techniques, or by starting with a cylindrical tube having the desired inner and outer diameters and removing the required portion of the cylindrical tube wall by, for example, laser cutting or water cutting to achieve the desired shape of the intermediate cylindrical element 3. However, alternatively, any 3D printing method may be used.

[0034]

[0054] Material removal can be carried out by different techniques, such as conventional chipping techniques including laser cutting, photochemical etching, deep pressing, drilling, or milling, high-pressure water jet cutting systems, or any suitable material removal process available. Preferably, laser cutting is used because it allows for very precise and clean material removal under reasonable economic conditions. The processes mentioned above are convenient because the cylindrical element 3 can be manufactured in essentially one process without requiring further steps to connect different parts of the intermediate cylindrical element, as is required in conventional fixtures where conventional control cables must be connected to the ends in some way. The same type of technique can be used to produce the inner and outer cylindrical elements 2 and 4, each having its respective flexible parts 6, 8, 18, and 20. These flexible portions 6, 8, 18, and 20 may be manufactured as hinges resulting from cutting any desired pattern from a cylindrical element, for example, by using one of the methods described in European Patent Application No. 08004373.0 filed October 3, 2008, page 5, lines 15-26, but any other suitable process may be used to produce the flexible portions.

[0035]

[0055] It can be observed that the devices shown in Figures 4 to 10 are known from the International Publication of the Prior Art, No. 2020 / 214027. The present invention can also be applied to these devices.

[0036]

[0056] Figure 4 shows an exemplary embodiment of the longitudinal (maneuvering) element 16 obtained after providing longitudinal slots 70 in the wall of the intermediate cylindrical element 3 that interconnects the proximal flexible zone 14 and the distal flexible zone 16 as described above. Here, the maneuvering wire 16 is at least partially helical around the longitudinal axis of the instrument such that the ends of each maneuvering element 16 in the proximal part of the instrument are positioned at an angular orientation around a different longitudinal axis than the ends of the same maneuvering wire 16 in the distal part of the instrument. If the maneuvering wire 16 were positioned in a linear orientation, when the instrument in the proximal part bends in a particular plane, the instrument in the distal part bends in the same plane, but in the opposite direction by 180 degrees. This helical structure of the maneuvering wire 16 allows for the effect that when the instrument in the proximal part bends in a particular plane, the instrument in the distal part may bend in a different plane, or in the same direction in the same plane. A preferred helical structure may be such that the ends of each control element 16 in the proximal part of the device are oriented in an orientation that is angularly shifted by 180 degrees around the longitudinal axis relative to the ends of the same control wire 16 in the distal part of the device. However, any other angularly shifted orientation, such as 90 degrees, is within the scope of this document. The slots 70 are dimensioned so that the movement of the control wire is guided by adjacent control wires when they are provided in a predetermined location within the controllable device. However, particularly in the flexible zones 13, 14 of the device, the width of the control wire 16 may be smaller to provide the device with the flexibility / bendability required in those locations.

[0037]

[0057] Figure 5 provides a detailed perspective view of the distal portion of an embodiment of an elongated tubular body 76 of a maneuverable instrument having two maneuverable distal bendable zones 74, 75, each operated by two bendable proximal zones 72, 73. Figure 5 shows that the elongated tubular body 76 comprises several coaxially arranged layers or cylindrical elements, including an outer cylindrical element 104 that terminates after the first distal flexibility zone 74 at the distal end portion 13. The distal end portion 13 of the outer cylindrical element 104 is fixedly attached to an adjacent cylindrical element 103 located inside the outer cylindrical element 104, for example, by spot welding at welding spot 100. However, any other suitable mounting method, including any mechanical snap-fit ​​connection or bonding with a suitable adhesive, may be used.

[0038]

[0058] Figure 6 provides a more detailed view of the distal end 13, which in this embodiment shows includes three coaxially arranged layers or cylindrical elements, namely, an inner cylindrical element 101, a first intermediate cylindrical element 102, and a second intermediate cylindrical element 103. All three distal ends of the inner cylindrical element 101, the first intermediate cylindrical element 102, and the second intermediate cylindrical element 103 are fixedly attached to each other. This may be done by spot welding at welding spots 100. However, any other suitable attachment method may be used, including any mechanical snap-fit ​​connection or bonding with a suitable adhesive. The attachment points may be on the edges of the inner cylindrical element 101, the first intermediate cylindrical element 102, and the second intermediate cylindrical element 103, as shown in the figure. However, these attachment points may also be located at some distance from these edges, preferably between the edges and the location of the flexible zone 75.

[0039]

[0059] It will be obvious to those skilled in the art that the elongated tubular body 76 shown in Figure 5 comprises a total of four cylindrical elements. The elongated tubular body 76 according to the embodiment shown in Figure 5 comprises two intermediate cylindrical elements 102 and 103 in which the control members of the control arrangement are located. However, more or fewer cylindrical elements may be provided if desired.

[0040]

[0060] The control arrangement in an exemplary embodiment of the elongated tubular body 76 shown in Figure 5 comprises two flexible zones 72, 73 at the proximal end 11 of the elongated tubular body 76, two flexible zones 74, 75 at the distal end 13 of the elongated tubular body 76, and a control member positioned between the associated flexible zones at the proximal end 11 and the distal end 13. An exemplary actual arrangement of the control member is shown in Figure 7, which provides a schematic longitudinal section view of an exemplary embodiment of the elongated tubular body 76 as shown in Figure 5.

[0041]

[0061] In this embodiment, the flexible zones 72, 73, 74, and 75 are implemented by providing slits 72a, 73a, 74a, and 75a, respectively, in each cylindrical element. Such slits 72a, 73a, 74a, and 75a may be arranged in any suitable pattern such that the flexible zones 72, 73, 74, and 75 have the desired flexibility in the longitudinal and tangential directions according to the desired design.

[0042]

[0062] Figure 7 shows longitudinal cross-sectional views of the four layers or cylindrical elements mentioned above, namely the inner cylindrical element 101, the first intermediate cylindrical element 102, the second intermediate cylindrical element 103, and the outer cylindrical element 104.

[0043]

[0063] The inner cylindrical element 101, viewed along its length from the distal end to the proximal end of the instrument, comprises a rigid ring 111 positioned at the distal end 13 of the maneuverable instrument 76, a first flexible portion 112, a first intermediate rigid portion 113, a second flexible portion 114, a second intermediate rigid portion 115, a third flexible portion 116, a third intermediate rigid portion 117, a fourth flexible portion 118, and a rigid end portion 119 positioned at the proximal end portion 11 of the maneuverable instrument.

[0044]

[0064] The first intermediate cylindrical element 102, viewed along its length from the distal end to the proximal end of the instrument, comprises a rigid ring 121, a first flexible portion 122, a first intermediate rigid portion 123, a second flexible portion 124, a second intermediate rigid portion 125, a third flexible portion 126, a third intermediate rigid portion 127, a fourth flexible portion 128, and a rigid end portion 129. Portions 122, 123, 124, 125, 126, 127, and 128 together form a steering wire 120 that can be moved longitudinally like a wire. The longitudinal dimensions of the rigid ring 121, first flexible portion 122, first intermediate rigid portion 123, second flexible portion 124, second intermediate rigid portion 125, third flexible portion 126, third intermediate rigid portion 127, fourth flexible portion 128, and rigid end portion 129 of the first intermediate element 102 are aligned with, preferably substantially equal to, the longitudinal dimensions of the rigid ring 111, first flexible portion 112, first intermediate rigid portion 113, second flexible portion 114, second intermediate rigid portion 115, third flexible portion 116, third intermediate rigid portion 117, fourth flexible portion 118, and rigid end portion 119 of the inner cylindrical element 101, and are also in the same locations as these portions. In this explanation, "approximately equal" means that each identical dimension is equal within a margin of less than 10%, preferably less than 5%.

[0045]

[0065] Similarly, the first intermediate cylindrical element 102 comprises one or more other control wires, one of which is indicated by reference number 120a.

[0046]

[0066] The second intermediate cylindrical element 103, viewed along its length from the distal end to the proximal end of the instrument, comprises a first rigid ring 131, a first flexible portion 132, a second rigid ring 133, a second flexible portion 134, a first intermediate rigid portion 135, a first intermediate flexible portion 136, a second intermediate rigid portion 137, a second intermediate flexible portion 138, and a rigid end portion 139. The portions 133, 134, 135, and 136 together form a steering wire 130 that can be moved longitudinally like a wire. The longitudinal dimensions of the first flexible portion 132, first intermediate rigid portion 135, first intermediate flexible portion 136, second intermediate rigid portion 137, second intermediate flexible portion 138, and rigid end portion 139 of the second intermediate cylinder 103, together with the first rigid ring 131, second rigid ring 133, and second flexible portion 134, are aligned with, preferably approximately equal to, the longitudinal dimensions of the first intermediate element 102, the first flexible portion 111, first flexible portion 112, first intermediate rigid portion 113, second flexible portion 114, second intermediate rigid portion 115, third flexible portion 116, third intermediate rigid portion 117, fourth flexible portion 118, and rigid end portion 119, respectively, and are located in the same places as these portions.

[0047]

[0067] Similarly, the second intermediate cylindrical element 103 comprises one or more other control wires, one of which is indicated by reference number 130a.

[0048]

[0068] The outer cylindrical element 104, viewed along its length from the distal end to the proximal end of the device, comprises a first rigid ring 141, a first flexible portion 142, a first intermediate rigid portion 143, a second flexible portion 144, and a second rigid ring 145. The longitudinal dimensions of the first flexible portion 142, the first intermediate rigid portion 143, and the second flexible portion 144 of the outer cylindrical element 104 are aligned with, preferably approximately equal to, the longitudinal dimensions of the second flexible portion 134, the first intermediate rigid portion 135, and the first intermediate flexible portion 136 of the second intermediate element 103, and are located in the same places as these portions. The rigid ring 141 has approximately the same length as the rigid ring 133 and is fixedly attached to the rigid ring, for example, by spot welding or adhesive. Preferably, the rigid ring 145 overlaps the second intermediate rigid portion 137 only to the extent required to provide a sufficiently secure attachment between the rigid ring 145 and the second intermediate rigid portion 137, for example, by spot welding or adhesive bonding. The rigid rings 111, 121, and 131 are attached to each other, for example, by spot welding or adhesive bonding. This may be done at their edges or at a distance from these edges.

[0049]

[0069] In one embodiment, the same may apply to rigid end portions 119, 129, and 139, which may be attached to each other in a comparable manner. However, the structure may be such that the diameter of the cylindrical element in the proximal portion is greater or smaller than the diameter in the distal portion. In such an embodiment, the structure in the proximal portion differs from that shown in Figure 7. As a result of the increase or decrease in diameter, amplification or damping is achieved, i.e., the bending angle of the flexible zone in the distal portion is greater or smaller than the bending angle of the corresponding flexible portion in the proximal portion.

[0050]

[0070] The inner and outer diameters of the cylindrical elements 101, 102, 103, and 104 are selected such that, at the same location along the elongated tubular body 76, the outer diameter of the inner cylindrical element 101 is slightly smaller than the inner diameter of the first intermediate cylindrical element 102, the outer diameter of the first intermediate cylindrical element 102 is slightly smaller than the inner diameter of the second intermediate cylindrical element 103, and the outer diameter of the second intermediate cylindrical element 103 is slightly smaller than the inner diameter of the outer cylindrical element 104, so that adjacent cylindrical elements can slide relative to each other. The dimensional setting must be such that a sliding fit is provided between adjacent elements. The gap between adjacent elements may typically be around 0.02 to 0.1 mm, but depends on the specific application and material used. The gap may be smaller than the wall thickness of the control wire to prevent overlapping configurations of the control wire. Usually, it is sufficient to limit the gap to about 30% to 40% of the wall thickness of the control wire.

[0051]

[0071] As shown in Figure 7, the flexible zone 72 of the proximal end 11 is connected to the flexible zone 74 of the distal end 13 by portions 134, 135, and 136 of the second intermediate cylindrical element 103, which form a first set of steering wires for the steering arrangement of the maneuverable instrument. Furthermore, the flexible zone 73 of the proximal end 11 is connected to the flexible zone 75 of the distal end 13 by portions 122, 123, 124, 125, 126, 127, and 128 of the first intermediate cylindrical element 102, which form a second set of steering wires for the steering arrangement. The use of the structure described above makes it possible to use the maneuverable instrument 76 for double bending. The operating principle of this structure will be explained with reference to the example shown in Figures 8 and 9.

[0052]

[0072] For convenience, as shown in Figures 7, 8, and 9, the different parts of the cylindrical elements 101, 102, 103, and 104 are grouped into zones 151 to 160, which are defined as follows: Zone 151 comprises rigid rings 111, 121, and 131. Zone 152 comprises parts 112, 122, and 132. Zone 153 comprises rigid rings 133 and 141 and parts 113 and 123. Zone 154 comprises parts 114, 124, 134, and 142. Zone 155 comprises parts 115, 125, 135, and 143. Zone 156 comprises parts 116, 126, 136, and 144. Zone 157 comprises rigid ring 145 and parts of parts 117, 127, and 137 located in the same place as rigid ring 145. Zone 158 comprises portions 117, 127, and 137 outside Zone 157. Zone 159 comprises portions 118, 128, and 138. Finally, Zone 160 comprises rigid end portions 119, 129, and 139.

[0053]

[0073] To deflect at least a portion of the distal end 13 of the controllable instrument, a bending force can be applied to zone 158 in any radial direction. According to the example shown in Figures 8 and 9, zone 158 is bent downward relative to zone 155. As a result, zone 156 is bent downward. A first set of control wires, comprising portions 134, 135, and 136 of a second intermediate cylindrical element 103 positioned between a second intermediate rigid portion 137 and a second rigid ring 133, transmits the downward bend of zone 156 to an upward bend of zone 154 relative to zone 155 by the longitudinal displacement of the first set of control wires. This is shown in both Figures 8 and 9.

[0054]

[0074] Note that the exemplary downward bend of zone 156 results only in an upward bend of zone 154 at the distal end of the device, as shown in Figure 8. The bending of zone 152 resulting from the bending of zone 156 is prevented by zone 153, which is positioned between zones 152 and 154. Subsequently, when any radial bending force is applied to zone 160, zone 159 is also bent. As shown in Figure 9, zone 160 is bent upward relative to its position shown in Figure 8. As a result, zone 159 is bent upward. A second set of steering wires, comprising portions 122, 123, 124, 125, 126, 127 and 128 of the first intermediate cylindrical element 102 positioned between the rigid ring 121 and the rigid end portion 129, transmits the upward bend of zone 159 to a downward bend of zone 152 relative to its position shown in Figure 8, through the longitudinal displacement of the second set of steering wires.

[0055]

[0075] Figure 9 further illustrates that the initial bending of the instrument in zone 154, as shown in Figure 8, is dominated solely by the bending of zone 156, while the bending of zone 152 is dominated solely by the bending of zone 159, as described above, thus maintaining the bending of the instrument in zone 154. The fact that zones 152 and 154 are bendable independently of each other makes it possible to give the distal end 13 of the maneuverable instrument independent positions and longitudinal axes. In particular, the distal end 13 can take an advantageous S-shape. Those skilled in the art will understand that the ability to bend zones 152 and 154 independently of each other greatly enhances the maneuverability of the distal end 13 and thus the entire maneuverable instrument.

[0056]

[0076] More specifically, the length of the flexible portion shown in Figures 7 to 9 can be varied to accommodate specific requirements regarding the bending radius and overall length of the distal end 13 and proximal end 11 of the maneuverable device, or to accommodate the amplification or attenuation ratio of bending between at least a portion of the proximal end 11 and at least a portion of the distal end 13.

[0057]

[0077] In the illustrated embodiment, the control wire comprises one or more sets of control wires forming an integral portion of one or more intermediate cylindrical elements 102, 103. Preferably, the control wire comprises the remaining portion of the walls of the intermediate cylindrical elements 102, 103 after longitudinal slits defining the remaining control wires are provided in the walls of the intermediate cylindrical elements 102, 103.

[0058]

[0078] Figure 10 shows a 3D view of an example of a controllable instrument. Similar reference numbers refer to the same elements in other figures. These descriptions are not repeated here. The instrument comprises five coaxial cylindrical elements 202–210. The inner cylindrical element 210 is surrounded by an intermediate cylindrical element 208, the intermediate cylindrical element 208 is surrounded by an intermediate cylindrical element 206, the intermediate cylindrical element 206 is surrounded by an intermediate cylindrical element 204, and the intermediate cylindrical element 204 is finally surrounded by an outer cylindrical element 202. The inner intermediate cylindrical elements may be made of flexible helical springs. The proximal and distal ends of the instrument are indicated by reference numbers 226 and 227, respectively.

[0059]

[0079] As shown in the figure, the device 76 here has a flexible zone 77 in its intermediate portion between the flexible zones 72 and 74. That is, the intermediate cylindrical element 204 (located on its outer surface within the region of the flexible zone 77) is provided with a slotted structure to give the intermediate cylindrical element the desired flexibility. The longitudinal length of the slotted structure in the flexible zone 77 depends on the desired application. It may be the same length as the entire portion between the flexible zones 72 and 74. All other cylindrical elements 206, 208, and 210 inside the intermediate cylindrical element 204 are also flexible within the flexible zone 77. These cylindrical elements having steering wires within the flexible zone 77 are flexible by definition. Others are provided with suitable hinges, preferably made by suitable slotted structures.

[0060]

[0080] Some locations within the body require specially designed instruments. For example, by making the middle section 12 of the instrument fully flexible, it can be used in areas within the body that are only accessible through curved natural access guides / channels, such as the large intestine, the stomach via the esophagus, or the heart via curved blood vessels.

[0061]

[0081] The instrument may be designed, for example, to be used as a colonoscope. Figure 11 shows a schematic diagram of a colonoscope 42 in use. The colonoscope 42 is inserted into the large intestine 30 of the human body. Typically, the large intestine 30 has several nearly right-angle sections 32, 34, 36, and 38. If the surgeon needs to operate on a region of the large intestine 30 upstream from the right-angle section 32, the colonoscope 42 needs to be inserted into the large intestine 30 along a distance of up to 1.5 meters. Furthermore, the colonoscope 42 needs to be flexible so that it can be easily guided through all the right-angle sections 32-38 of the large intestine 30 from the anus without risking damage to the inner wall of the large intestine 30.

[0062]

[0082] During surgery, several invasive instruments are typically inserted through the colonoscope 42 to provide one or more tools for several functions at the distal end 44 of the colonoscope. In a colonoscope, such tools typically include a camera lens and an illumination element. To help the surgeon maneuver the camera view to a desired location and view within the colon 30, the distal end is typically deflectable in all angular directions from the longitudinal axis. This also applies to instruments inserted with tool 2. This can be implemented by providing one or more deflectable zones in such instruments, such as the deflectable zones 16, 17 of the instruments shown in Figures 5 to 10. These distal deflectable zones are controlled by appropriate maneuvering cables housed within the instrument, connected to an appropriate maneuvering mechanism at the proximal end of the instrument.

[0063]

[0083] Figure 12 shows a schematic diagram of the gastroscopy endoscope 56 in use. The gastroscopy endoscope 56 is inserted into the stomach 50 of the human body through the mouth, oral cavity / throat 54 and esophagus 52. The gastroscopy endoscope 56 needs to be guided through several curved / angled sections, especially when the surgeon needs to operate on the lower portion of the stomach 50. Therefore, the gastroscopy endoscope 56 needs to be flexible so as to minimize the risk of damaging the mouth / throat 54, esophagus 52, and the inner wall of the stomach 50.

[0064]

[0084] During surgery, several invasive instruments are typically inserted through the gastroscopy endoscope 56 to provide one or more tools for several functions at the distal end 59 of the gastroscopy endoscope. In a gastroscopy endoscope, such tools typically include a camera lens and an illumination element. To help the surgeon maneuver the camera view to a desired location and direction within the stomach 50, the distal end 59 of the gastroscopy endoscope 56 is typically deflectable in all angular directions from the longitudinal axis. This also applies to instruments inserted with tool 2. This can be implemented by providing one or more deflectable zones in such instruments, such as the deflectable zones 16, 17 of the instruments shown in Figures 5 to 10. These distal deflectable zones are controlled by appropriate control cables housed within the instrument, connected to the appropriate control mechanism of these instruments.

[0065]

[0085] The instruments according to the present invention may be used in such colonoscopies and gastroscopies, but may also be used in other applications, such as instruments designed to enter the pulmonary bronchi. Requirements for such instruments include, for example, instruments longer than 1 meter and having a relatively small diameter to fit into the working channels within or attached to colonoscopies and gastroscopies, exhibiting high rotational rigidity, high longitudinal rigidity, high bending flexibility along their entire length, and precise and repeatable deflection of a maneuverable tip.

[0066]

[0086] To better understand the issues addressed in this document, a detailed description of a prior art flexible maneuverable device with a Bowden cable is first provided with reference to Figures 13-15.

[0067]

[0087] A Bowden cable, as known from prior art, can be defined as a type of flexible cable used to transmit mechanical force or energy by the movement of an inner cable relative to a hollow outer cable housing. The housing is a composite structure overall, consisting of an inner lining, a longitudinally incompressible layer such as a helical winding or a steel wire sheath, and a protective outer covering. The cable housing is often called a coiled tube. Here, the term "maneuvering wire guide" is used for the outer cable housing.

[0068]

[0088] Figure 13 shows a prior art instrument comprising a steerable tip and a flexible body, wherein the Bowden cable arrangement is located within a length compensation section at one end of the Bowden cable. Each Bowden cable arrangement comprises a steering wire and a surrounding steering wire guide. The steering wire guide is attached to the instrument body within the distal end in front of the proximal end of the steerable tip, and also within the proximal end. The length compensation section is positioned between the distal end of the guide and the proximal end of the guide, preferably within the proximal end of the instrument. In this figure, the length compensation section has a simple curved geometric shape that can be shortened or elongated. However, the prior art offers many different solutions regarding the length compensation section.

[0069]

[0089] Figure 13 shows in more detail a flexible, maneuverable device 1300 having a tip section 1301, a flexible body section 1303, a length compensation section 1305, and a steering section 1307 which may have a handle. The length compensation section 1305 may be located in another longitudinal location, for example, somewhere inside the body section 1303.

[0070]

[0090] The control wires 1309(1) and 1309(2) extend from the control section 1307 to the tip section 1301 to allow the tip section 1301 to bend relative to the main section 1303. Inside the main section 1303 and the length compensation section 1305, the control wires 1309(1) and 1309(2) are positioned inside the control wire guides 1311(1) and 1311(2), respectively. The control wire guides 1311(1) and 1311(2) are held in fixed positions 1317(1) and 1317(2), respectively, at the transition between the tip section 1301 and the main section 1303. Similarly, the control wire guides 1311(1) and 1311(2) are held in fixed positions 1319(1) and 1319(2) respectively at the transition between the length compensation section 1305 and the control section 1307.

[0071]

[0091] Figure 14 shows the same apparatus as in Figure 13, but in this case the main body section 1303 is bent. The tip section 1301 is not bent. The portions of the control wires 1309(1) and 1309(2) inside the tip section 1301 have a length L1. The curved portion of the main body section 1303, i.e., the inner curve of the hinge 1313 portion, has a length L3, and the outer curve has a length L4. The initial length of the control wire guides 1311(1) and 1311(2) inside the main body section 1303, i.e., in Figure 13, is L5. The total length of the control wires 1309(1) and 1309(2) inside the length compensation section 1305 and inside the control section 1307 is L2.

[0072]

[0092] Due to the bending, L3 becomes shorter than the initial control wire guide length L5, and L4 becomes longer than the initial control wire guide length L5. If it is desired that the bent L1 and L2 be equal to the unbent L1 and L2, in other words, if it is not desired that the control device in the tip or control section 1307 be deflected by the bending of the body, the length difference between L5 and L3 or L4 needs to be absorbed by the length compensation section 1305 as shown in the figure. In this figure, the length compensation section 1305 absorbs the length difference by increasing the curvature height inward of the control wire guide section 1311(1) having the relevant portion of control wire 1309(1) (this can absorb the increased length of the control wire guide section 1311(1) having the control wire 1309(1) outside the main section 1303) and decreasing the curvature height inward of the control wire guide section 1311(2) having the relevant portion of control wire 1309(2) (this can absorb the shortened length of the control wire guide section 1311(2) having the control wire 1309(2) outside the main section 1303). In this way, the tip deflection is completely isolated from the main deflection.

[0073]

[0093] Figure 15 shows the same apparatus as in Figures 13 and 14, but in this case the control device is deflected to control the apparatus tip section 1301. When the tip section 1301 is deflected as shown, a tensile force is generated in the control wire 1309(2) and a push force is generated in the control wire 1309(1). As a result, a compressive or tensile force is generated in the corresponding areas of the body section 1303 and tip section 1301. The control wire guides 1311(1) and 1311(2) are flexible enough to allow the body section to bend, but are very rigid in their longitudinal direction so that they can withstand compressive or tensile forces without significant deformation. The length compensation section 1305 itself has longitudinal rigidity designed to withstand compressive or tensile forces caused by pulling or pushing the control wires 1309(1) and 1309(2) without significant deformation. Therefore, in this configuration, compressive and tensile forces are completely absorbed by the Bowden cable arrangement inside the length compensation section 1305. Consequently, the main body section 1303 is no longer compressed or stretched, and therefore not bent. In this way, maneuvering of the main body section, which would result in undesirable end-effects, is prevented.

[0074]

[0094] Figures 16 to 31c represent embodiments of the present invention. Figures 16 to 30 relate to a flexible, invasive, and maneuverable device in which the control wire is mounted by control wires 16i (i=1, 2…I) fabricated from a portion of one or more tubes, for example by (laser) cutting a suitable slot pattern within such one or more tubes, as described in detail with reference to Figures 1 to 10. As described in detail, the control wire guide is mounted by a control wire guide portion, also fabricated from one or more tubes. Embodiments in Figures 31a to 31c can also be mounted by a classic control wire and coil tube.

[0075]

[0095] Figure 16 shows a longitudinal section view through a flexible, maneuverable invasive instrument having a tip section 1613, a flexible body section 1615, a length compensation section 1617, and a control section 1618 which may include a handle, a deflectable control unit, or a robotic control unit. The length compensation section 1617 may be located in another longitudinal location, for example, somewhere inside the body section 1615, or it may be integrated inside the control section 1618. The right-hand side is the proximal end of the instrument, and the left-hand side is the distal end of the instrument.

[0076]

[0096] The illustrated apparatus is constructed of five tubes arranged coaxially around a central axis 1622. However, other numbers may also be applicable. The inner tube 1601 is located inside the apparatus and is flexible at least inside the body section 1615, but rigid in its longitudinal direction. To achieve this purpose, the inner tube 1601 may be provided with a suitable hinge 1609 constructed within the body section 1615 by providing a suitable pattern of slots in the inner tube 1601. The portion of the inner tube 1601 at the transition between the tip section 1613 and the body section 1615 is indicated by reference numeral 1611, and the portion inside the length compensation section 1617 is indicated by reference numeral 1607.

[0077]

[0097] The first intermediate tube 1619 surrounds the inner tube 1601. The first intermediate tube 1619 has a control section portion 1619(1) which may be ring-shaped overall, a plurality of inner control wire guide portions 1619(2, i) within the length compensation section 1617, i.e., one for each control wire 16(i), a body section portion 1619(3) which may be ring-shaped, and a tip section portion 1619(4) which may be ring-shaped and may be provided with one or more suitable hinges. The first intermediate tube 1619 and the inner tube 1601 are preferably attached to each other by, for example, laser welding, bonding, etc., at the transition between the tip section 1613 and the body section 1615, and at the proximal side between the length compensation section 1617 and the control section 1618. The body section portion 1619(3) is flexible at least within the flexible portion of the body section 1615.

[0078]

[0098] A second intermediate tube 1620 (see, for example, Figure 18a) surrounds the first intermediate tube 1619. The second intermediate tube 1620 has steering wires 16(i) extending from the proximal end to the distal end of the instrument. These steering wires must be flexible at least within the flexible portion of the tip section 1613, within the flexible portion of the body section 1615, and inside the length compensating section 1617.

[0079]

[0099] The third intermediate tube 1621 surrounds the second intermediate tube 1620. The third intermediate tube 1621 has a control section portion 1621(1) which may be ring-shaped overall, a plurality of outer control wire guide portions 1621(2, i), i.e., one for each control wire 16(i), a length compensation section 1617, a body section portion 1621(3) which may be ring-shaped, and a tip section portion 1621(4) which may be ring-shaped and may be provided with one or more suitable hinges. The body section portion 1621(3) is flexible at least within the flexible portion of the body section 1615.

[0080]

[0100] At the distal end of the device, that is, beyond the distal portion of the flexible tip section 1613, all control wires 16(i) are attached to at least one of the first and third intermediate tubes 1619 and 1621 to enable tensile and pushing forces to be transmitted to the tip section 1613.

[0081]

[0101] The outer tube 1602 surrounds the third intermediate tube 1621. In the illustrated example, the outer tube 1602 has, viewed from the proximal end to the distal end, a steering section portion 1604 which may be ring-shaped overall, one or more openings in the length compensation section 1617 which may allow the length compensation portions of tubes 1619, 1620, and 1621 to increase in their extensions away from the central axis 1622 if desired, a ring-shaped portion 1603, a flexible portion 1605, and a ring-shaped portion 1606. The ring-shaped portion 1606 may be attached to the third intermediate tube 1621 at the transition between the tip section 1613 and the body section 1615.

[0082]

[0102] Figure 17 shows an enlarged external view of the length compensation section 1617. In this figure, the external control wire guide section 1621(2,3), located above the control wire 16(3) (not visible in this figure), can also be seen. The control wire guide sections 1619(2,i) and 1621(2,i) are bent radially and outward with the control element 16(i) between them. The control element 16(i) is then guided radially by the control wire guide sections 1619(2,i) and 1621(2,i). Note that Figures 25A and 25B show more details on how the control wire guide sections 1619(2,i) and 1621(2,i) can be constructed.

[0083]

[0103] Figure 18a shows an embodiment in which the proximal instrument end is configured to be coupled to, for example, a robotic control device or a separate portable control device. To achieve this objective, each control wire 16(i) may be provided with radially positioned openings 16(i, 1) within the control section 1618 and inside appropriately sized slots in the third intermediate tube 1921. Each opening 16(i, 1) is configured to receive these mechanical coupling units so that the robotic control device can operate the control wire 16(i) individually by the associated mechanical coupling units of the robotic control device. Other coupling mechanisms may be used instead of the openings 16(i, 1).

[0084]

[0104] Figure 18b shows the same instrument, but in this case the proximal end of the instrument is configured to steer the distal end by a bendable section in the same manner as shown in Figures 1 to 10. Naturally, other steering means or other known steering methods, such as a gimbal handle, can be anticipated.

[0085]

[0105] The control wire cross-sections may have a substantially rectangular shape so that they are easily bent radially but not easily bent tangentially. In this case, there is no need to guide the control wires 16(i) tangentially within the length compensation section 1617. That is, these wires remain between the inner control wire guide portion 1619(2,i) and the outer control wire guide portion 1621(2,i) inside the length compensation section 1617 while being pulled or pushed.

[0086]

[0106] When a control element 16(i) that is also flexible in the tangential direction is used, it may also be necessary to guide the control wire 16(i) in the tangential direction of the device. This can be achieved as shown in Figures 19 and 20.

[0087]

[0107] Figure 19 shows the tangential lip 1623 of the inner control wire guide portion 1619(2,i), which can be bent upward toward the outer control wire guide portion 1621(2,i) and can be permanently attached to the outer control wire guide portion 1621(2,i) by, for example, brazing, soldering, welding or a snap-fit ​​connection.

[0088]

[0108] Figure 20 shows another embodiment in which the control wire is prevented from moving tangentially by island portions located within each opening in each control wire 16(i), which are attached to at least one of the control wire guide portions 1619(2,1) and 1621(2,1). As shown in Figure 20, in the length compensation section 1617, the control wire 16(1) is provided with a plurality of openings 1627(j) (j=1, 2, 3, ..., J; six are shown), each having an island portion 1625(j) inside. The island portions 1625(j) are also cut from the tube 1620 and, even after the cut is complete, remain connected to the adjacent material of the control wire 16(1) by one or more crushing elements 1629(j). Next, during assembly, these island sections 1625(j) can be permanently attached at the mounting section 1626(j) to at least one of the control wire guide sections 1619(2,1) and 1621(2,1). This attachment may be done by laser welding, by adhesive, or by making the distance between the control wire guide sections 1619(2,1) and 1621(2,1) greater than the thickness of the control wire 16(1), thus creating a radial cage and bending the lip inward into the opening 1627(j) to reduce radial friction. In this way, a radial spacer is created, the details of which are described in International Publication No. 2019009710A1. After attachment by laser welding, for example, the crushing element 1629(j) will crush during the initial activation of the control wire 16(1).

[0089]

[0109] The crushing element 1629(j) must be designed as follows: Before crushing, each crushing element 1629(j) is attached to the opposing portion of the island 1627(j) and the steering wire 16(i). These opposing portions of the island 1627(j) and the steering wire 16(i) have a geometric shape such that the stress within the crushing element 1629(j) is higher than that within the surrounding material and / or structure. Therefore, when a deflection or sufficiently large force is applied to the structure having the crushing element 1629(j), the stress within the crushing element 1629(j) rises above the yield stress of the tube material, causing permanent deflection of the crushing element 1629(j). Further deflection or higher forces result in the stress reaching the maximum tensile stress, causing the crushing element 1629(j) to fracture. Other mechanisms for fracture of the fracture element are achieved by subjecting the fracture element 1629(j) to low or high cycle fatigue. The stress within the fracture element 1629(j) is increased above the fatigue limit, causing fatigue fracture. In all cases, the stress within the surrounding structure / material, i.e., the island 1627(j) and the steering wire 16(i), remains below at least the yield stress of the tube material.

[0090]

[0110] The examples in Figures 19 and 20 can be implemented using any control wire 16(i).

[0091]

[0111] Thus, the embodiments of Figures 19 and 20 realize tangential guidance of the control wire 16(i), where the inner control wire guide portion 1619(2,i) may be attached to the outer control wire guide portion 1621(2,i) such that a substantially completely closed control wire guide is created for each control wire. Naturally, other methods can be expected to create tangential guidance while simultaneously mounting the inner control wire guide portion 1619(2,i) and the outer control wire guide portion 1621(2,i) radially. In the remaining section of the device, the control wire 16(i) may be guided radially and tangentially by the surrounding tube and a portion of the tube 1620 including appropriate spacers placed next to the control element. Radial spacers, such as those described in International Publication No. 2019009710, can also be applied.

[0092]

[0112] Figures 21a and 21b show details of a manufactured control wire guide in which the elastic deformation of the curved shape is made more flexible by cutting slots within the control wire guide sections 1619(2,i) and 1621(2,i) so that the bending stiffness is lower than that of a solid strip, and so that when the curved shape is bent, the length of the outer control wire guide section 1621(2,i) matches the length of the inner control wire guide section 1619(2,i), or vice versa. Figure 21a shows such slots 1633 in the inner control wire guide sections 1619(2,1) and 1619(2,4), while Figure 21b shows such slots 1639 in the control wire guide sections 1621(2,1) and 1621(2,4).

[0093]

[0113] Figure 21a shows the situation immediately after the cutting process is complete, with the control wire guide sections 1619(2, 1) and 1619(2, 4) still attached to the surrounding material of the tube 1619 by the crushing element 1637. The figure also shows the attachment section 1635 to which the attachment section 1626(1) of the island section 1625(1) may be attached. As shown above, other island sections 1625(j) may be similarly attached to the inner control wire guide section 1619(2, 1).

[0094]

[0114] Figure 21b shows the situation immediately after the cutting process is complete, with the steering wire guide sections 1621(2,1) and 1621(2,4) still attached to the surrounding material of the tube 1621 by the crushing element 1641. The figure also shows the attachment section 1643(j) to which the attachment section 1626(j) of the island section 1625(j) may be attached.

[0095]

[0115] As a result, the length-compensating section 1617 becomes more longitudinally flexible, requiring less force to compress or tensile. This further results in a more easily bendable main body section 1615 of the device. Another possible outcome is that the longitudinal flexibility of the inner and outer steering wire guide sections 1619(2,i), 1621(2,i) can be balanced such that when the curved shape within the length-compensating section 1617 is bent outward or inward, the average length of the inner and outer steering wire guide sections 1619(2,i), 1621(2,i) remains exactly equal to the length of the enclosed steering wire 16(i). The bending flexibility must be designed so that the longitudinal flexibility of the length-compensating section 1617 can still withstand the tip steering force without significant stretching or shortening.

[0096]

[0116] Figure 22 shows a simplified proposal of a multi-tube device according to the present invention. Sets of inner and outer steering wire guide portions 1619(2,i), 1621(2,i), each having a corresponding portion of the steering wire 16(i), form a length compensation element pre-formed to a specific curve.

[0097]

[0117] Figure 23 shows how the same multi-tube device and length compensation element as in Figure 22 operate as previously described. When the main body section 1615 is bent, the curved shape of the length compensation element deforms to absorb the difference in length between the inner and outer steering wire guide sections 1619(2,i), 1621(2,i) inside the main body section 1615, and the steering wire 16(i), which is initiated by the bending of the main body segment 1615. Note that in this way, the bending of the main body section 1615 does not affect the deflection angles of the tip section 1613 and the steering section 1618.

[0098]

[0118] Figures 24a and 24b show embodiments of the instrument according to the present invention in which a change in length of the length compensation section 1615, as viewed perpendicular to the central axis 1622, can be prevented while maneuvering the distal tip of the instrument.

[0099]

[0119] Figure 24a shows the main body section 1615 in an unbent, and therefore neutral position, while Figure 24b shows the main body section 1615 bent and the length compensation section 1617 in operation.

[0100]

[0120] In this embodiment, a square frame element 1645 is provided, having a first bar 1645(1) and a second bar 1645(2) extending in a first direction, and a third bar 1645(3) and a fourth bar 1645(4) extending in a second direction perpendicular to the first direction. The right-hand side of Figures 24a and 25b shows this square frame element 1645 as viewed longitudinally towards the distal end of the device. Reference numeral A(i) indicates a set of control wires 16(i) having control wire guide portions 1619(2,i) and 1621(2,i) around them. These sets A(i) have a curved shape as shown on the left-hand side of Figures 24a and 24b. Each vertex of sets A(1), A(2), A(3), and A(4) is slidably connected to bars 1645(4), 1645(3), 1645(1), and 1645(2) respectively, using connecting units 1645(4,1), 1645(3,1), 1645(1,1), and 1645(2,1), respectively. Thus, each vertex of set A(i) can slide along its associated bars 1645(1), 1645(2), 1645(3), and 1645(4) in a direction perpendicular to the radial direction, although its movement is restricted to the radial direction.

[0101]

[0121] It can be shown that the distance between two opposing sets A(1) / A(3) and A(2) / A(4) changes slightly when the main body section 1615 bends. This slight change in distance can be compensated by using bars 1645(1), 1645(2), 1645(3), and 1645(4) which are radially elastic to the fixture 1600.

[0102]

[0122] An interesting application is the situation shown in Figure 24a or 24b, for example, in which a fixed square frame element 1645 is held in place while steering the distal end by moving a steering wire 16(i) in the longitudinal direction. Here, all sets A(i) are held in place and resist any tendency for the body section 1615 to bend (further) due to the steering wire force applied.

[0103]

[0123] Another advantage of connecting the vertices of the curved length compensation element is that this can improve the response of the length compensation element. When the main section 1615 is bent, one side of the length compensation section 1617 is activated by the tensile force within the guide element, while the opposite side of the length compensation section 1617 is activated by the extrusive force of the opposing guide element. If there is a difference in the magnitude of the forces, or if there is a difference in movement due to their lengths, play, bending effects, etc., it is better to directly couple the deformation of the Bowden cable elements 1619(2,i) and 1621(2,i) on one side of the length compensation section 1617 to the Bowden cable elements 1619(2,i) and 1621(2,i) on the opposite side of the length compensation section 1617. Naturally, many other mechanisms for coupling or freezing the shape or length of the length compensation section can be anticipated.

[0104]

[0124] Figures 13 to 24b illustrate an apparatus according to the present invention in which the Bowden cable guide is constructed from a separate first intermediate tube 1619 and a separate second intermediate tube 1621, and the steering wire 16(i) is fabricated separately between tubes 1620. However, if supporting inner tubes 1601 and supporting outer tubes 1602 are added to provide structure (hinge) to the bendable section, five tubes are required to construct this apparatus. A more efficient method is to fabricate the steering wire 16(i) and its guide section within a single tube. Embodiments of such an implementation are described below.

[0105]

[0125] Figure 25A shows an embodiment of the device according to the present invention, in which the inner control wire guide portion 1619(2,1) and a substantial portion of the control wire 16(1) are made from a single tube, namely the first intermediate tube 1619. A third intermediate tube 1621 is not shown in Figure 25A but is shown in Figure 25B.

[0106]

[0126] In this embodiment, the inner control wire 16(1) has the following portions when viewed from the proximal end to the distal end: a flexible control wire portion 16(1, 2) in the control section 1618, a control wire length compensation portion 16(1, 3) in the length compensation section 1617, a control wire attachment portion 16(1, 4) in the transition between the length compensation section 1617 and the body section 1615, and a control wire body section portion 16(1, 5). The control wire guide portion 1619(2, 1) and the control wire body section portion 16(1, 5) are both fabricated within the intermediate tube 1619, while all the other mentioned portions 16(1, 2), 16(1, 3), and 16(1, 4) are fabricated within the tube 1620.

[0107]

[0127] The control wire mounting portion 16(1, 4) is provided with an opening 1648 in which a sliding element 1647 is located. This sliding element 1647 is attached to the first intermediate tube 1619, for example by laser welding, bonding, etc., so that the control wire mounting portion 16(1, 4) can slide along the sliding element 1647 in the longitudinal direction. Furthermore, the control wire mounting portion 16(1, 4) is attached to the control wire body section portion 16(1, 5). This attachment can be made by any suitable attachment method, preferably by laser welding. In this way, any pushing or pulling action applied to the flexible control wire portion 16(1, 2) is directly transmitted to the same movement of the control wire body section portion 16(1, 5) (and further to the tip section 1613).

[0108]

[0128] The same configuration applies to all control wires 16(i).

[0109]

[0129] After the product shown in Figure 25A is finished, a third intermediate tube 1621, including the outer control wire guide portion 1621(2,1), is slid on the product as shown in Figure 26. The outer control wire guide portion 1621(2,1) is attached at its distal end to the sliding element 1647 at the mounting point 1655. This can be done, for example, by laser welding, bonding, etc. Furthermore, the third intermediate tube 1621 is flexible in longitudinal locations where the flexible control wire portion 16(1,2) is positioned to create a bendable control section 1618. This is done here by a suitable pattern of slots 1653.

[0110]

[0130] Figure 25B shows a finished assembly in which the completed device is made up of three tubes 1619, 1620, and 1621. The first intermediate tube 1619 includes both the inner control wire guide section 1619(2, i) and the main body section control wire section 16(i, 5). The third intermediate tube 1621 includes the outer control wire guide section 1621(2, i) and a further outer body structure.

[0111]

[0131] Further inner tubes 1601 or outer tubes 1602 are not required, but it will be understood that one or both of these may also be applied.

[0112]

[0132] Figures 26A to 26F show alternatives to the embodiments in Figures 16 to 25B. The same reference numerals refer to the same or similar elements. Features described with reference to Figures 16 to 25B that are not repeated in Figures 26A to 26F may also apply to Figures 26A to 26F, unless physically impossible.

[0113]

[0133] Figure 26A shows a 3D side view without the outer tube 1602. In fact, such an outer tube 1602 may be applied, but it is not required. This system has a Bowden cable structure cut from the tube. The difference from the extension system described above is that this structure is helical around the central axis of the instrument. Its function is almost identical; that is, when the instrument shaft is bent within the flexible body section 1615, the control elements in the length compensation section 1617, which are on the same side as the inside of the bend in the instrument shaft, bend outward away from the central axis, gaining a shorter path length. The maneuvering elements 16(i) located inside this bend in the flexible body section have less longitudinal space inside the flexible body section, but gain more longitudinal space in the length compensation section by these control elements.

[0114]

[0134] Conversely, control elements in the length compensation section located on the same side as the outside of the bend in the instrument shaft gain a longer path length and are forced toward the central axis. Maneuvering elements 16(i) located on this outside of the bend in the flexible body section gain a larger longitudinal space inside the flexible body section, but within the length compensation section, these control elements gain a smaller longitudinal space.

[0115]

[0135] As a result, changes in the length of the steering element inside the flexible body section 1615 due to bending are compensated by the control element inside the length compensation section 1617, and undesirable steering of the connecting end section 1613 is avoided.

[0116]

[0136] Figure 26A shows the exterior of an embodiment of a length compensation section 1617 of an instrument made of five coaxially arranged tubes, namely an inner tube 1601, a further intermediate tube 1608, a first intermediate tube 1619, a second intermediate tube 1620, and a third intermediate tube 1621. The inner tube 1601 may be omitted in some embodiments. On the right side is the proximal steering section 1618, the middle section is the length compensation section 1617, and on the left side, some detail of the flexible body section 1615 is shown.

[0117]

[0137] In this embodiment, the rightmost portion of the third intermediate tube 1621 inside the control section 1618 has a solid portion without a hinge in the form of a slot pattern. However, the control section 1618 may be flexible itself, as described with reference to Figures 1 to 10 and Figure 18B, so that bending of the control section 1618 controls the longitudinal movement of the control wire 16(i), and therefore the control of the tip section 1613.

[0118]

[0138] This embodiment shows a Bowden cable structure for four control wires 16(i). However, this embodiment is not limited to such a number. The number may be one or more. Within the length compensation section 1617 are provided four strip-like outer control wire guide portions 1621(2,i) separated by slots. Each of the outer control wire guide portions 1621(2,i) is helical around the central axis of the instrument. The amount of tangential helix from its proximal end to its distal end may be 360 ​​degrees. However, the required amount of tangential helix depends on the specific application and may therefore be greater or less than 360 degrees. A suitable amount may be in the range of 10 to 1440 degrees, for example, in the range of 45 to 1080 degrees.

[0119]

[0139] Each of the four outer control wire guide sections 1621(2,i) is attached at its distal end to an outer control wire guide section end 1621(2,i)E. Figure 26A shows that each of these outer control wire guide section ends 1621(2,i)E is attached to a portion of the second intermediate tube 1620 at two attachment points 1655a, 1655b, which will be described in more detail later. Each of these outer control wire guide section ends 1621(2,i)E is positioned at a distance from the body section portion 1621(3) in a stationary state (without bending of the flexible body section 1613). Thus, each of these can move longitudinally in both the proximal and distal directions to a specific designed range, independently of all the other outer control wire guide section ends 1621(2,i)E.

[0120]

[0140] Figure 26A shows the control wire 16(i) at i=1 and i=3 on the distal side of the outer control wire guide portion end 1621(2,i)E. Reference numerals 1601(1) and 1601(3) refer to portions of the inner tube 1601 which will be revealed later. Several portions of the second intermediate tube 1620 and the first intermediate tube 1619 can also be seen. These will be described next with reference to Figure 26B, which shows these portions in more detail.

[0121]

[0141] Figure 26B shows the same apparatus as in Figure 26A, but without the third intermediate tube 1621. Figure 26B shows a portion of the four control wires 16(i). Viewed distally, the tangential clockwise order is i=1, 4, 2, 3. The tangential distance between the centers of two adjacent control wires is 90 degrees. In the control section 1618, the space between control wires 16(1,2) and 16(4,2) is filled by spacer 1620(1,4), the space between control wires 16(4,2) and 16(2,2) is filled by spacer 1620(1,2), the space between control wires 16(2,2) and 16(3,2) is filled by spacer 1620(1,3), and the space between control wires 16(3,2) and 16(1,2) is filled by spacer 1620(1,1). These spacers 1620(1,i), where i=1, 2, 3, and 4, are separated from adjacent control wire portions 16(i,2) by small slots so that they guide adjacent control wires 16(i,2) longitudinally and prevent tangential movement of control wires 16(i,2) within the control section 1618.

[0122]

[0142] In the transition between the control section 1618 and the length compensation section 1617, each spacer 1620(1,i) is attached to the two longitudinal guide element length compensation sections 1620a(2,i) and 1620b(2,i). Inside the length compensation section 1617, the steering wire portion 16(1,3) is positioned between the longitudinal guide element length compensation portions 1620a(2,4) and 1620b(2,1), the steering wire portion 16(4,3) is positioned between the longitudinal guide element length compensation portions 1620a(2,2) and 1620b(2,4), the steering wire portion 16(2,3) is positioned between the longitudinal guide element length compensation portions 1620a(2,3) and 1620b(2,2), and the steering wire portion 16(3,3) is positioned between the longitudinal guide element length compensation portions 1620a(2,1) and 1620b(2,3).

[0123]

[0143] Each of the longitudinal guide element length compensation sections, 1620a(2,4) / 1620b(2,1), 1620a(2,2) / 1620b(2,4), 1620a(2,3) / 1620b(2,2), and 1620a(2,1) / 1620b(2,3), is separated from each of the control wire sections 16(1,3), 16(4,3), 16(2,3), and 16(3,3) by small slots, so as to guide each of the control wire sections 16(1,3), 16(4,3), 16(2,3), and 16(3,3) in the longitudinal direction and to prevent independent tangential movement of each of the control wires 16(1,3), 16(4,3), 16(2,3), and 16(3,3) within the length compensation section 1617.

[0124]

[0144] Towards the distal end, each of the two longitudinal guide element length compensation portions 1620a(2,i) and 1620b(2,i) is attached to the end portions 1620a(2,i)E and 1620b(2,i)E, respectively. The two end portions 1620a(2,i)E and 1620b(2,i)E are separated by slots so that they can move independently in the longitudinal direction. In one embodiment, the slots are configured to prevent the two end portions 1620a(2,i)E and 1620b(2,i)E from moving tangentially toward each other.

[0125]

[0145] All end portions 1620a(2,i)E, 1620b(2,i)E are positioned such that, in a stationary state, there is a distal free space that allows them to move distally. In the illustrated embodiment, this free space ends at the transition between the length compensation section 1617 and the flexible body section 1615. The portion of the control wire 16(i) inside this free space is indicated by reference numeral 16(i,4), while the portion of the control wire 16(i) inside the flexible body section 1615 is indicated by reference numeral 16(i,5). In the illustrated embodiment, the control wire portion 16(i,5) is wider than the portion inside its free space at the transition between the length compensation section 1617 and the flexible body section 1615, but this is not required.

[0126]

[0146] In the assembled state of this embodiment, the third intermediate tube 1621 is located outside the second intermediate tube 1620, and each of the outer control wire guide portions 1621(2,i) is aligned with one control wire portion 16(i,3), thereby covering the control wire portion 16(i,3) along its entire length and preventing any radial movement of the control wire portion 16(i,3) independent of the radial movement of the outer control wire guide portions 1621(2,i).

[0127]

[0147] In one embodiment, in order to further prevent the independent tangential movement of each of the control wire portions 16(1,3), 16(4,3), 16(2,3), and 16(3,3), the end portion 1620a of each set of longitudinal guide element length compensation portions 1620a(2,4) / 1620b(2,1), 1620a(2,2) / 1620b(2,4), 1620a(2,3) / 1620b(2,2), and 1620a(2,1) / 1620b(2,3) Each set of (2,4)E / 1620b(2,1)E, 1620a(2,2)E / 1620b(2,4)E, 1620a(2,3)E / 1620b(2,2)E, and 1620a(2,1)E / 1620b(2,3)E is attached to one end portion 1621(2,1)E, 1621(2,3)E, 1621(2,2)E, and 1621(2,4)E respectively at mounting locations 1655a and 1655b (see Figure 26A). Therefore, the end portions of each set of 1620a(2,4)E / 1620b(2,1)E, 1620a(2,2)E / 1620b(2,4)E, 1620a(2,3)E / 1620b(2,2)E, and 1620a(2,1)E / 1620b(2,3)E are fixed in their tangential and longitudinal movements relative to each other.

[0128]

[0148] The slot pattern provided within the first intermediate tube 1619, as shown in Figure 26C, is very similar to that within the third intermediate tube 1621, as shown in Figure 26A.

[0129]

[0149] In this embodiment, referring to Figure 26C, the rightmost portion of the first intermediate tube 1619 inside the steering section 1618 comprises a solid portion, which may have one or more slotted patterns, for example, to form a hinge.

[0130]

[0150] Within the length compensation section 1617, four strip-like inner control wire guide sections 1619(2,i) are provided, separated by slots. Each of the inner control wire guide sections 1619(2,i) is spiral around the central axis of the device in the same manner as the outer control wire guide sections 1621(2,i) and the control wire section 16(2,i).

[0131]

[0151] One of each of the four internal control wire guide sections 1619(2,i) is attached at its distal end to an internal control wire guide section end 1619(2,i)E.

[0132]

[0152] The end portions 1620a(2,4)E / 1620b(2,1)E of each set of longitudinal guide element length compensation portions 1620a(2,4) / 1620b(2,1), 1620a(2,2) / 1620b(2,4), 1620a(2,3) / 1620b(2,2), and 1620a(2,1) / 1620b(2,3) within the second intermediate tube 1620 (see Figure 26B) Each set of 1620a(2,2)E / 1620b(2,4)E, 1620a(2,3)E / 1620b(2,2)E, and 1620a(2,1)E / 1620b(2,3)E is attached to one end portion 1619(2,1)E, 1619(2,3)E, 1619(2,2)E, and 1619(2,4)E respectively at the mounting location 1656. Therefore, the end portions of each set of 1620a(2,4)E / 1620b(2,1)E, 1620a(2,2)E / 1620b(2,4)E, 1620a(2,3)E / 1620b(2,2)E, and 1620a(2,1)E / 1620b(2,3)E are fixed in their tangential and longitudinal movements relative to each other.

[0133]

[0153] Each of these internal control wire guide portion ends 1619(2,i)E is positioned at a distance from the flexible body section 1615 when stationary (i.e., without bending of the flexible body section 1613). Thus, each of these can move longitudinally in both the proximal and distal directions to a specific designed range, independently of all the other internal control wire guide portion ends 1619(2,i)E.

[0134]

[0154] Next, moving to Figure 26D, a portion of the inner tube 1601 is shown inserted into a further intermediate tube 1608. In the assembled state, these are located inside the first intermediate tube 1619. At the proximal end, i.e., within the control section 1618, the further intermediate tube 1608 comprises further intermediate tube portions, which may be solid or have a suitable slotted pattern for hinges, depending on the required function of the portion. On the proximal side of the length compensation section 1617, in this embodiment, there are no portions of the further intermediate tube 1608. On the distal side of the length compensation section 1617, the further intermediate tube 1608 comprises four (in this embodiment, the same number as the control wires 16(i)) further intermediate tube shiftable portions 1608(i). These further intermediate tube shiftable portions 1608(i) extend toward the proximal end of the tip, where they are mounted so as not to move longitudinally in the tip section 1613. Adjacent further intermediate tube shiftable portions 1608(i) are separated by slots so that they can shift longitudinally back and forth along the inner tube 1601. These slots are preferably manufactured to be as small as possible to avoid tangential play between them. Inside the flexible body section 1615, further intermediate tubes 1608 may include, for example, steering wire portions attached to steering wire portions 16(1, 5).

[0135]

[0155] Furthermore, referring to Figure 26D, one of each inner control wire guide portion end 1619(2,i)E is attached to one such further intermediate tube shiftable portion 1608(i), for example, at mounting location 1673.

[0136]

[0156] As shown in Figures 26A to 26C, each outer control wire guide portion 1621(2,i) has a width along its length such that it covers the outer surface of each control wire portion 16(2,i) when viewed radially. Furthermore, each inner control wire guide portion 1619(2,i) has a width along its length such that it covers the inner surface of each control wire portion 16(2,i) when viewed radially.

[0137]

[0157] The widths of the outer control wire guide portions 1621(2,1), 1621(2,4), 1621(2,2), and 1621(2,3) may be equal to the width of the control wire portion 16(1,3) plus the width of the set of longitudinal guide element length compensation portions 1620a(2,4) / 1620b(2,1), the width of the control wire portion 16(4,3) plus the width of the set of longitudinal guide element length compensation portions 1620a(2,2) / 1620b(2,4), the width of the control wire portion 16(2,3) plus the width of the set of longitudinal guide element length compensation portions 1620a(2,3) / 1620b(2,2), and the width of the control wire portion 16(3,3) plus the width of the set of longitudinal guide element length compensation portions 1620a(2,1) / 1620b(2,3).

[0138]

[0158] Furthermore, the widths of the inner control wire guide portions 1619(2,1), 1619(2,4), 1619(2,2), and 1619(2,3) may be equal to the widths of the outer control wire guide portions 1621(2,1), 1621(2,4), 1621(2,2), and 1621(2,3).

[0139]

[0159] As a result, each control wire section 16(i, 3) is located inside the channel within the length compensation section 1617. That is, control wire section 16(1, 3) is located within the channel formed by the inner control wire guide section 1619(2, 1), the longitudinal guide element length compensation sections 1620a(2, 4) / 1620b(2, 1), and the outer control wire guide section 1621(2, 1). Control wire section 16(4, 3) is located within the channel formed by the inner control wire guide section 1619(2, 4), the longitudinal guide element length compensation sections 1620a(2, 2) / 1620b(2, 4), and the outer control wire guide section 1621(2, 4). The control wire section 16(2,3) is located within a channel formed by the inner control wire guide section 1619(2,2), the longitudinal guide element length compensation section 1620a(2,3) / 1620b(2,2), and the outer control wire guide section 1621(2,2). The control wire section 16(3,3) is located within a channel formed by the inner control wire guide section 1619(2,3), the longitudinal guide element length compensation section 1620a(2,1) / 1620b(2,3), and the outer control wire guide section 1621(2,3).

[0140]

[0160] The length compensation section 1617 in the embodiments of Figures 26A to 26D functions in the following manner. This will be explained with reference to the opposing control wires 16(1) and 16(2) in this embodiment. This explanation is the same for other opposing control wires. References are made to Figures 26E (side view) and 26F (perspective view), in which the device is rotated slightly tangentially with respect to Figures 26A to 26D.

[0141]

[0161] Assume that the flexible body section 1615 is bent so that the proximal end of the further intermediate tube shiftable portion 1608(1) is pushed toward the proximal end. Then, the proximal end of the further intermediate tube shiftable portion 1608(1), the inner steering wire guide portion end 1619(2,1)E, the set of longitudinal guide element length compensating portions 1620a(2,4)E / 1620b(2,1)E, and the outer guide steering wire guide portion end 1621(2,1)E, all of which are mounted together, slide toward the proximal end. As a result, the helical portions of the inner steering wire guide portion 1619(2,1), the longitudinal guide element length compensation portions 1620a(2,4) / 1620b(2,1), and the outer steering wire guide portion 1621(2,1) within the length compensation section 1617 move away from the central axis. This makes a longer path length available to the steering wire 16(1) within the length compensation section 1617, which is necessary to compensate for the longitudinal movement of the steering wire portion 16(1,5) within the length compensation section 1617 to a certain range due to the bending of the flexible body section 1615.

[0142]

[0162] The bending of the flexible body portion 1615 causes the proximal end opposite the further intermediate tube shiftable portion 1608(2) to be pulled toward the distal end. The proximal end of the further intermediate tube shiftable portion 1608(2), the inner steering wire guide portion end 1619(2,2)E, the set of longitudinal guide element length compensation portions 1620a(2,3)E / 1620b(2,2)E, and the outer guide steering wire guide portion end 1621(2,2)E, all of which are attached, to slide toward the distal end. As a result, the helical portions of the inner steering wire guide portion 1619(2,2), the longitudinal guide element length compensation portion 1620a(2,3) / 1620b(2,2), and the outer steering wire guide portion 1621(2,2) within the length compensation section 1617 move toward the central axis. This makes a shorter path length available to the steering wire 16(2) within the length compensation section 1617, which is necessary to compensate for the longitudinal movement of the steering wire portion (2,4) within the flexible body section 1615 due to the bending of the flexible body section 1615.

[0143]

[0163] The inward bending of the flexible body section 1615 may be such that the steering wire sections 16(3,4) / 16(3,3) and 16(4,4) / 16(4,3) do not move at all and do not require length compensation. However, depending on the direction of the bending, they may move, and this movement is compensated in a similar manner within the length compensation section 1617.

[0144]

[0164] Therefore, all movement of the steering wire portion 16(i, 5) due to bending of the flexible body section 1615 inside that section is compensated by the Bowden cable structure inside the length compensation section 1617, and the tip section 1613 is not bent unintentionally.

[0145]

[0165] Naturally, further embodiments can be envisioned in which the main structure, control wires, and Bowden cable elements are combined within the tubes, with the aim of reducing the number of tubes required and making the assembly of such devices as easy as possible.

[0146]

[0166] Figure 27 shows an embodiment in which a compressible or expandable curved shape of the length compensation section 1617 can be fabricated tangentially to the instrument without increasing the overall diameter of the instrument and without the need for a separate molding process. In this embodiment, a separate structure for the steering wire guide is not required. The steering wire 16(i) is guided radially by the inner and outer tubes and tangentially by a longitudinal guide element located adjacent to the steering wire 16(i). Furthermore, it can be expected that many other shapes are possible, as long as the shape is compressible or expandable in the longitudinal direction and the friction with respect to the steering wire 16(i) is kept at an acceptable level. These latter observations are also applicable to radially formed shapes as shown in Figures 13 to 26F.

[0147]

[0167] In the implementation example in Figure 27, only the inner tube 1601 and a portion of the intermediate tube 1620 are shown. The outer tube 1621 is not shown. As shown in Figures 26A to 26F, inside the length compensation section 1617, the steering wire portion 16(1,3) is positioned between the longitudinal guide element length compensation portions 1620a(2,4) and 1620b(2,1), the steering wire portion 16(4,3) is positioned between the longitudinal guide element length compensation portions 1620a(2,2) and 1620b(2,4), the steering wire portion 16(2,3) is positioned between the longitudinal guide element length compensation portions 1620a(2,3) and 1620b(2,2), and the steering wire portion 16(3,3) is positioned between the longitudinal guide element length compensation portions 1620a(2,1) and 1620b(2,3). These longitudinal guide element length compensation portions may be joined by bridge elements within the inner tube 1601 or the outer tube 1602 to create a more defined channel. Each control wire 16(i) has a control wire control section portion 16(i, 2), a control wire length compensation section portion 16(i, 3), and a control wire body section portion 16(i, 5) (these end portions are not shown but may be similar to those in other embodiments). Here, each spacer 1620(1, i), as shown in the transition between the length compensation section 1617 and the control section 1618 in Figure 26B, is separated into two portions 1620a(1, i) and 1620b(1, i), each of which is attached at location 1657 to the inner tube 1601 or the outer tube 1621, or both, for example by laser welding, bonding, etc. Such a division is not necessary.

[0148]

[0168] Within the main body section 1615, the control wire portion 16(1,5) is positioned between the longitudinal guide element main body portions 1620a(3,4) and 1620b(3,1), the control wire portion 16(4,5) is positioned between the longitudinal guide element main body portions 1620a(3,2) and 1620b(3,4), the control wire portion 16(2,5) is positioned between the longitudinal guide element main body portions 1620a(3,3) and 1620b(3,2), and the control wire portion 16(3,5) is positioned between the longitudinal guide element main body portions 1620a(3,1) and 1620b(3,3). These latter longitudinal guide element body portions extend to the transition between the body section 1615 and the tip section 1613, where they are attached to the inner tube 1601 or the outer tube 1602 or both, for example by laser welding or bonding, to prevent longitudinal movement at that location. The embodiment in Figure 27 operates in essentially the same way as those in Figures 16 to 26F, provided that each first portion of the control wire (16(i)) and the associated control wire guide portion is configured as a length compensation element having a configuration that is curved only in the tangential direction, and is configured to deform to absorb the change in length of the second portion of the control wire (16(i)) inside the flexible body section (1615) due to the bending of the flexible body section (1615).

[0149]

[0169] Figures 28a and 28b show embodiments of a length compensation section 1617 that can be constructed within a single tube 1620 and does not require radial formation. In practice, this length compensation section 1617 can be completely enclosed by a single inner tube 1619 and a single outer tube 1621, as in the embodiment of Figure 27. Figure 28a shows a plan view, and Figure 28b shows a 3D view "cut in that manner". These figures show embodiments in which two control wires 16(1) and 16(2) are rotated relative to each other and positioned at 180 degrees. However, if the diameter of the tube is large enough, three or more control wires may be applied. Embodiments with only one control wire can also be fabricated.

[0150]

[0170] Each control wire 16(i) is divided into two parts, namely a first part and a second part. The first part is provided with a projection 16(i, 9) extending tangentially at a predetermined angle greater than 0 degrees but less than 90 degrees. For example, an angle greater than 30 degrees but less than 80 degrees. The second part, attached to the distal end of the tip section 1613, has a recess 16(i, 8) located, for example, between two extensions 16(i, 6) and 16(i, 7). The recess 16(i, 8) is molded to slidably receive the projection 16(i, 9). To achieve this objective, in one embodiment, the recess 16(i, 8) has the same shape as the projection 16(i, 9), i.e., it also extends tangentially at the same angle.

[0151]

[0171] Between the control wires 16(i), control wire guide elements are provided. These control wire guide elements are attached to the body of the device. In the illustrated embodiment, they are positioned 90 degrees tangentially rotated from the control wires 16(i). These control wire guide elements are grouped into sets of two control wire guide elements. Each set has a first control wire guide element 1620(3,1), 1620(3,3) and a second control wire guide element 1620(3,2), 1620(3,4). Each of the first control wire guide elements 1620(3,1), 1620(3,3) has a recess 1620(3,1,1), 1620(3,3,1). Each second control wire guide element 1620(3,2), 1620(3,4) has projections 1620(3,2,1), 1620(3,4,1) that are received within the recesses 1620(3,1,1), 1620(3,3,1) of the first control wire guide elements 1620(3,1), 1620(3,3). Both the projections 1620(3,2,1), 1620(3,4,1) and the recesses 1620(3,1,1), 1620(3,3,1) extend tangentially at a predetermined angle greater than 0 degrees but less than 90 degrees, for example, greater than 30 degrees and less than 80 degrees. These angles may be the same as applied within the control wire projections 16(i,9) and control wire recesses 16(i,8).

[0152]

[0172] The first control wire guide elements 1620(3,1) and 1620(3,3) are connected to the body of the instrument within the area of ​​the proximal end of the controllable tip section. The second control wire guide elements 1620(3,2) and 1620(3,4) are also connected to the appropriate parts of the body of the instrument.

[0153]

[0173] When the main body section 1615 of the device in Figures 28a and 28b is bent, the proximal ends of the first control wire guide elements 1620(3,1) and 1620(3,3) are displaced longitudinally over a certain length. This displacement causes the inclined projections 1620(3,2,1) and 1620(3,4,1) to slide tangentially in and out of the inclined recesses 1620(3,1,1) and 1620(3,3,1). Consequently, the second control wire guide elements 1620(3,2) and 1620(3,4) move tangentially. In this movement, this also tangentially displaces the first portion of the control wire 16(i), which is longitudinally attached to the control device at the proximal end of the device. When the first portion of the control wire 16(i) attached to the control device is displaced tangentially, this displaces the second portion of the control wire 16(i) longitudinally. By appropriately selecting the tangential inclination angles of the projections and recesses of all elements, the change in length of the control wire 16(i) can be compensated so that the tip section 1613 is not deflected by the bending of the body section 1615. This structure then acts as a length compensation element.

[0154]

[0174] Furthermore, if the control wire is moved longitudinally to deflect the tip section 613 in a desired manner, this is not affected by the illustrated structure. The longitudinal movement of the first portion of the control wire 16(i) is transmitted to the same longitudinal movement of the second portion of the control wire 16(i).

[0155]

[0175] Figures 28a and 28b illustrate an embodiment of a sliding mechanism that simulates the longitudinal displacement of a passive control wire end by the exact same amount and direction as the control wire end. Naturally, other sliding or lever mechanisms can be anticipated.

[0156]

[0176] Figures 27 and 28a / 28b show only two possible embodiments in which the length compensation section 1617 is cut within a single tube 1620. More shapes are possible, and it can be anticipated that the length compensation section may also be constructed using two or more tubes.

[0157]

[0177] Figure 29 shows an embodiment in which the Bowden cable arrangement within the length compensation section 1617 extends radially inward toward the central axis 1622. For clarity, Figure 29 shows only the tube 1619 and its length compensation portion 1619(2,i). The other tubes 1620 and 1621 have a similar design in the length compensation section 1617. Furthermore, the inner tube 1601 and outer tube 1602 may be similarly applied. In order to provide sufficient inner space for each set of elements 1619(2,i), 16(i), and 1621(2,i) inside the length compensation section 1617, such tangentially adjacent sets 1619(2,i), 16(i), and 1621(2,i) may be shifted along a certain longitudinal distance so as shown that they do not come into contact with each other when they bend inward toward the central axis 1622.

[0158]

[0178] Figure 30 shows an embodiment having at least one longitudinal guide element length compensation portion 1620(2,2) located tangentially adjacent to each control wire 16(i) within a length compensation section 1617. The elements within the length compensation section are curved radially outward. The figure shows one such longitudinal guide element length compensation portion 1620(2,2) for each control wire 16(i), but there may be one on each side. Each longitudinal guide element length compensation portion 1620(2,2) is cut from the same tube 1620 from which the control wire 16(i) is cut. They are separated from each other by small slots, which may be as small as those resulting from the minimum laser beam used to create the slots.

[0159]

[0179] Each longitudinal guide element length compensation portion 1620(2,2) is part of the longitudinal guide elements 1620(2,1), 1620(2,2), and 1620(2,3). In the transition between the length compensation section 1617 and the control section 1618, each control wire control section portion 16(i,2) is tangentially positioned between two adjacent proximal longitudinal guide element portions 1620(2,1) attached to the inner tube 1619 or the outer tube 1621, or both, for example by laser welding, bonding, etc. Within the main body section 1615, each control wire main body section portion 16(i, 4) extends to the transition between the main body section 1615 and the tip section 1613, where it is tangentially positioned between two adjacent longitudinal guide element main body portions 1620(2, 3) attached to the inner tube 1619 or the outer tube 1621 or both, for example by laser welding, bonding, etc., to prevent longitudinal movement at that location. Here again, the separation slot may be very small, i.e., as small as the minimum laser beam used to create the slot.

[0160]

[0180] Figure 30 also shows one or more cover plates 1659, 1661 within the length compensation section 1617. That is, one or more cover plates 1659, for example, cut from the outer tube 1621, cover the steering wire 16(i) on its radially outward side and are attached to adjacent longitudinal guide element length compensation sections 1620(2,2) by, for example, laser welding, adhesive, etc. Furthermore, one or more cover plates 1661, for example, cut from the inner tube 1619, cover the steering wire 16(i) on its radially inward side and are attached to adjacent longitudinal guide element length compensation sections 1620(2,2) by, for example, laser welding, adhesive, etc. Thus, within the length compensation section 1617, each steering wire 16(i) is guided by adjacent guide elements on at least three sides. Guidance on four sides may be implemented.

[0161]

[0181] Figures 31a to 31c show different embodiments of an electromechanical length compensation section 1617 that can be applied to both a maneuverable and deflectable device having a wire in the form of a classic cable 1309(i) and a maneuver wire 16(i) manufactured from a tube. In the latter case, the maneuverable and deflectable device may be one of the embodiments described in this document with reference to any one of the earlier Figures 13 to 27, Figure 19, or Figure 30. In this case, the tip section is indicated by both reference numerals 1301 and 1613, and the body section is indicated by both reference numerals 1303 and 1615. When designed for robotic applications, the length compensation section 1617 can be manufactured as an integral part of a robotic maneuver section that can be coupled to a maneuver wire guide and the maneuver wire 16(i).

[0162]

[0182] Figure 31a shows an embodiment in which the proximal end of the control wire guide is coupled to a sensor 1663(i). Sensors 1663(i) are connected to the processor 1670 to transmit their respective sensor signals 1667(i) to the processor 1670. These sensors 1663(i) measure the magnitude and longitudinal direction of the movement of the proximal end of each control wire guide when the main body sections 1303, 1615 are bent. Each sensor signal 1667(i) is an indication of the magnitude and direction of this movement. The processor 1670 generates a compensation signal 1669(i) for each of the multiple actuators 1665(i) in response to the sensor signals 1667(i). Each actuator 1665(i) is coupled to one control wire 1309(i) / control wire 16(i) such that each control wire 1309(i) / control wire 16(i) moves along the same direction and path length as the proximal end of each control wire guide, as measured by sensor 1663(i). In this way, each set of one sensor 1663(i) and one actuator 1665(i) functions as a length compensation unit for one control wire 1309(i) / control wire 16(i) and its associated control wire guide.

[0163]

[0183] Alternatively, a separate set of processors may be connected to and applied to one set of sensors 1663(i) and one set of actuators 1665(i) to perform the functions mentioned above. Each of the separate sets of processors may be located either near or inside each sensor 1663(i) or near or inside each actuator 1665(i).

[0164]

[0184] Furthermore, in this example, each actuator 1665(i) is configured to move its steering wire 1309(i) / steering wire 16(i) so as to be controlled by an appropriate actuator signal generated by the processor 1670 to control the deflection of the tip sections 1301 / 1613. The processor 1670 can simultaneously generate compensation and actuation signals. This can be useful for actively steering the tip sections 1301 / 1613 while advancing the instrument through a curved channel, for example inside a human body.

[0165]

[0185] Each applied processor is equipped with a central processing unit CPU connected to appropriate memory units (RAM, ROM, EPROM, etc.) and appropriate input / output units. The memory units store appropriate computer programs that, when loaded by the CPU, provide the CPU with the capability to perform the required functions. The input units are configured to receive input signals from, for example, sensor 1663(i) and transmit them to the CPU for further processing. The output units are configured to receive output signals from the CPU and transmit them to external devices such as actuation motors 1665(i) and brakes 1671(i).

[0166]

[0186] Figure 31b shows the same setup as in Figure 31a, but this time each sensor 1663(i) is equipped with a brake device 1671(i), which is also coupled to the processor 1670. The brake devices are configured to allow or block the longitudinal movement of the proximal end of each steering wire guide. Each brake device 1671(i) can be activated by the processor 1670 with an appropriate brake control signal when the processor 1670 generates an actuation signal for the actuator 1665(i) to control the steering wire 1309(i) / steering wire 16(i) to deflect the tip section 1301 / 1613 without altering the current bent or unbent state of the main section 1303 / 1615. In this way, the steering wire guide is then kept in a stationary position, and as a result, the main section 1303 / 1615 is kept in its current, possibly bent, position. Therefore, activating control wire 1309(i) / control wire 16(i) does not constitute control of main section 1303 / 1615.

[0167]

[0187] Figure 31c shows another embodiment of the system as shown in Figure 31b, in which each actuator 1665(i) is mechanically coupled to the proximal end of its associated control wire guide and configured to move with the proximal end of the control wire guide during bending of the body section, and is configured to keep the distance at which the control wire 1309(i) / control wire 16(i) extends proximal outside its control wire guide constant unless a control signal is received by the actuator 1665(i). In this embodiment, the mechanical unit including the actuator 1665(i) may also be equipped with a brake device 1671(i) as shown in Figure 31b, which holds the actuator 1665(i), and therefore the proximal end of the control wire guide, in a specific fixed position as long as an activation signal is received. As can be expected, it is also possible to replace the control wire guide with a simpler element, such as a simple wire activating a sensor.

[0168]

[0188] As illustrated in Figures 14 and 15, it is possible to eliminate undesirable tip maneuver when the body of the device is bent, and by incorporating a length compensation section into a Bowden cable arrangement, it is possible to eliminate body maneuver when the tip is actively maneuvered. Figures 16 to 27 show embodiments in which the length compensation section is based on such a Bowden cable arrangement, and the length compensation is established by the simultaneous deformation of the radial or tangential maneuver wire guide element and the maneuver wire. As an alternative to deforming the length compensation section, Figures 28a and 28b illustrate an embodiment of a length compensation section having a sliding mechanism that mimics displacing the maneuver wire guide element longitudinally by the exact same amount and in the same direction as the maneuver wire end. The illustrated solutions are usable but have limitations with respect to the length compensation that can be obtained. The greater the length compensation must be, the greater the slope angle of the projection must also be. If the length compensation must be relatively large and the slope angle exceeds 40 or 50 degrees, the sliding friction may become so high that the mechanism can no longer operate, or the starting push or pull force within the main body length sensing element may become so high that it is unacceptable. Therefore, alternative sliding mechanisms for the length compensation section are schematically presented below with reference to Figures 32 to 42E.

[0169]

[0189] Figure 32 shows a schematic setup of the length compensation section 3200 to illustrate the principle of the embodiments shown in Figures 32 to 42H. This length compensation section 3200 is located between the flexible body section (shown as 1303 in Figure 13) and the control section (shown as 1307 in Figure 13) of the controllable instrument. Figure 32 shows a body length sensing element 3201 which has the same function as the control wire guide element in the embodiments shown in Figures 14 to 27 above, but differs in that this body length sensing element 3201 is used only for sensing the body length and does not have the primary function of the control wire guide. In this embodiment, it is assumed that the body length sensing element 3201 and the control wire 16(i) are located in the same plane. It is also assumed that the body length sensing element 3201 and the control wire 16(i) are guided by the surrounding structure so that they can move only in the longitudinal direction and not in the vertical direction or in a direction perpendicular to the plane of the figure.

[0170]

[0190] More specifically, Figure 32 shows a first wall 3202 extending transversely perpendicular to the longitudinal direction of the control wire 16(i), which is shown to have a first portion 16(i, 1) and a second portion 16(i, 2). The main body length sensing element 3201 is implemented as a strip extending in the same longitudinal direction as the control wire 16(i). The length compensation section 3200 also includes a second wall 3204 extending parallel to the first wall 3202 and a first slider 3218 that can slide transversely between the walls 3202 and 3204 as indicated by arrow dV. The first slider 3218 is provided with an opening 3203 that accommodates a second slider 3219, thereby allowing the second slider 3219 to slide back and forth within the opening 3203 in a direction parallel to the longitudinal direction as indicated by arrow dH.

[0171]

[0191] Here, the main body length sensing element 3201 extends into the space between the first wall 3202 and the second wall 3204 through a suitable opening in the first wall 3202. The main body length sensing element 3201 is provided with a projection 3206 that extends into the inner slot 3212 of the first slider 3218. Here, the slot 3212 is straight and extends at an angle of 0 < α1 < 90 degrees with respect to the longitudinal direction.

[0172]

[0192] The first control wire portion 16(i, 1) also extends into the space between the first wall 3202 and the second wall 3204 through a suitable opening in the first wall 3202. The first control wire portion 16(i, 1) is provided with a projection 3208 that extends into a slot 3214 inside the second slider 3219. Here, the slot 3214 is straight and extends at an angle of 0 < α2 < 90 degrees with respect to the transverse direction.

[0173]

[0193] The second control wire portion 16(i, 2) also extends into the space between the first wall 3202 and the second wall 3204 through a suitable opening in the second wall 3204, such that the first and second control wire portions 16(i, 1) and 16(i, 2) extend in opposite directions from the length compensation section 3200. The second control wire portion 16(i, 2) is provided with a projection 3210 that extends into a slot 3216 inside the second slider 3219, where the slot 3216 is straight and extends transversely.

[0174]

[0194] All projections 3206, 3208, and 3210 can be mounted as fixed projections that are rounded or molded to the geometric shape of the corresponding slot, or they can be, for example, pin and wheel structures to reduce sliding friction, as shown in Figures 33A, 33B, and 33C for projection 3206.

[0175]

[0195] In Figure 32, the body length sensing element 3201 is located, for example, within the inner curve of the curved fixture body, and therefore it has an excess length compared to the neutral line of the fixture body moving to the right in Figure 32. The angled slot 3212 pushes the first slider 3218 transversely upward over a distance H1, here by the horizontal movement of the body length sensing element 3201 over a distance La. This movement also moves a second slider 3219, which is connected to the first slider 3218 transversely but can move freely in the longitudinal direction, upward over a distance H2, in this case H1 = H2.

[0176]

[0196] When the second control wire portion 16(i, 2) is held stationary in place by, for example, a control input unit (manual or robotic) attached to the second control wire portion 16(i, 2), the slot 3216 to which the control wire 4b is internally connected extends transversely, so the second slider 3219 does not move longitudinally when it moves transversely upward. Due to the other angled slot 3214 in the second slider 3219, the end of the first control wire portion 16(i, 1) attached to the projection 3208 inside the angled slot 3214 is displaced longitudinally over a distance Lr when the second slider 3219 moves transversely upward together with the first slider 3218. If the inclination angle 90~α2 of slot 3214 in the second slider 3219 is the same as the inclination angle α1 of slot 3212 in the first slider 3218, the displacement Lr of the first control wire portion 16(i, 1) is made to be exactly the same as the displacement La of the main body length sensing element 3201. When control of the tip of the device (for example, located on the left-hand side in the drawing of Figure 32) is desired, the second control wire portion 16(i, 2) can be pulled or pushed longitudinally (for example, manually or by a robotic device), and this movement then pulls or pushes the second slider 3219 longitudinally as well. Since the first control wire section is also connected to the second slider 3219, the first control wire section 16(i, 1) is pulled or pushed longitudinally with the same longitudinal displacement as the second control wire section 16(i, 2), and control is achieved.

[0177]

[0197] It is observed that angle α1 may deviate from angle α2 such that displacements La and Lr may be different.

[0178]

[0198] The internal friction and starting force within the length compensation section 3200 strongly depend on the inclination angles α1 and α2 of the respective slots 3212 and 3214. For example, if slot 3212 in the first slider 3218 is close to the longitudinal direction, it can be understood that the starting force required to move the slider 3218 upward together with the main body length sensing element 3201 is very small, and the friction between the projection 3206 and slot 3212 is also very small. If slot 3212 in the first slider 3218 is close to the transverse direction, it can be understood that a very large starting force is required to move the first slider 3218 upward (or downward), and the friction between the projection 3206 and slot 3212 is also very large. At the same time, angle α2 must be minimized to allow projection 3208 to slide with minimal friction within slot 3214 after the first and second sliders 3218, 3219 move upward or downward, but to prevent projection 3208 from sliding easily within slot 3214 when the second control wire portion 16(i, 2) is pulled or pushed out. Therefore, it can be concluded that inclination angles α1 and α2 must be minimized as much as possible to keep friction and starting force at acceptable levels. In the above example, if it is desirable to minimize the inclination angles α1 and α2 of both slots 3212, 3214 for given displacements La, Lr and H1, H2, these inclination angles must be about 45 degrees. A suitable design range for both of these is between 35 and 55 degrees, preferably between 40 and 50 degrees.

[0179]

[0199] The mechanism in Figure 32 can be further optimized with respect to friction, starting force, and the length compensation that can be obtained, in combination with given length displacements La and Lr (where Lr is preferably equal to La to obtain correct length compensation), as shown in Figure 34.

[0180]

[0200] The difference between the embodiments in Figure 32 and Figure 34 is that the slot 3216 is no longer parallel to the transverse direction, but extends at an angle of 0 < α3 < 90 degrees with respect to the transverse direction. The angles α2 and α3 are oriented in opposite directions with respect to the transverse direction. The longitudinal displacement of the first control wire portion 16(i, 1) and its projection 3208 is shown by Lr1. The longitudinal displacement of the second control wire portion 16(i, 1) and its projection 3210 is shown by Lr2.

[0181]

[0201] In the schematic solution shown in Figure 34, the inclination angles α1, α2, and α3 of all slots 3212, 3214, and 3216 can be minimized as long as Lr2, in addition to Lr1, is equal to La for a given transverse displacement H1=H2. In this mechanism, all slots 3212, 3214, and 3216 can then have inclination angles α1, α2, and α3 that are less than 45 degrees. Given a given La and H1=H2, the maximum allowable starting force applied to the main body length sensing element 3201, the coefficient of friction, and the output required for the second steering wire section 16(i,2) can be known, then the optimal inclination angles α1, α2, and α3 of all slots, including slot 3212, in the slider 3218 can be calculated.

[0182]

[0202] Figure 35 shows an embodiment in which the second slider 3219 is replaced by a third slider 3219a and a fourth slider 3219b, both of which are positioned within the first slider 3218 so as to be able to move longitudinally rather than transversely relative to the first slider 3218. These longitudinal displacements are indicated by arrows dH1 and dH2, respectively.

[0183]

[0203] The projection 3210 attached to the second control wire section 16(i, 2) extends into the inner slot 3216 of the fourth slider 3219b. Here, the slot 3216 is straight and extends at an angle of 0 < α3 < 90 degrees with respect to the transverse direction. The angles α2 and α3 are oriented in opposite directions with respect to the transverse direction.

[0184]

[0204] The control wire 16(i) is provided with a third control section 16(i,3) positioned longitudinally between the first control section 16(i,1) and the second control wire section 16(i,2). The first end of the third wire section 16(i,3) is attached to a projection 3220 extending into the inner slot 3222 of the third slider 3219a at an angle of 0 < α4 < 90 degrees. The angles α2 and α4 are oriented in directions opposite to the transverse direction. The second end of the third wire section 16(i,3) opposite to the first end is attached to a projection 3224 extending into the inner slot 3226 of the fourth slider 3219b at an angle of 0 < α5 < 90 degrees. The angles α3 and α5 are oriented in directions opposite to the transverse direction.

[0185]

[0205] The longitudinal displacement of the first control wire portion 16(i, 1) and projection 3208 is indicated by Lr1. The longitudinal displacement of the second control wire portion 16(i, 2) and projection 3210 is indicated by Lr2. The longitudinal displacement of the third control wire portion 16(i, 3) and projection 3220 relative to the third slider 3219a is indicated by Lr4. The longitudinal displacement of the third control wire portion 16(i, 3) and projection 3224 relative to the fourth slider 3219b is indicated by Lr3.

[0186]

[0206] In the embodiment shown in Figure 35, the required longitudinal length change Lr = Lr1 + Lr2 + Lr3 + Lr4 of the control wire 16(i) is obtained by dividing the longitudinal displacement La over four slots 3214, 3216, 3222, and 3226, rather than two slots. In this case, it is clear that the inclination angles α1, α2, α3, α4, and α5 of all slots 3212, 3214, 3216, 3222, and 3226 can be further reduced, as long as Lr1 + Lr2 + Lr3 + Lr4 = La. Furthermore, a mechanism having three or more sliders 3219a and 3219b can also be envisioned to further reduce the inclination angles.

[0187]

[0207] It can be anticipated that there may be two or more groups of body length sensing elements. In Figure 36, two steering wires 16(i) and 16(i+1) inside the outer tube 3228 are schematically shown. The instrument has a tip section 1301, a first body section 1303a, and a second body section 1303b. Two groups of sensing elements are shown: 3201(i) / 3201(i+1) and 3203(i) / 3203(i+1). The first group of sensing elements 3201(i) and 3201(i+1) is mounted in location A within the distal part of the instrument body, and the second group of sensing elements 3203(i) and 3203(i+1) is mounted in location B. The steering wire 16(i) is mounted in location C. Each group of sensing elements has its own length compensation section within the proximal part of the instrument. An example is shown in Figure 37.

[0188]

[0208] Figure 37 shows a first length compensation section, as shown in Figure 34, and a second length compensation section, similarly. The second control wire section 16(i, 2) is then replaced by a third control wire section 16(i, 3). Furthermore, the wall 3204 also functions as the wall of the second length compensation section, and one of the sensing elements 3201(i) of the first group extends into the first slider 3218, as the sensing element 3201 in Figure 34.

[0189]

[0209] The second length compensation section comprises a third wall 3230 extending parallel to the first wall 3202 and the second wall 3204, and a third slider 3228 that can slide vertically between the walls 3204 and 3230 in the transverse direction as indicated by arrow dV2. The third slider 3228 is provided with an opening 3237 that accommodates a fourth slider 3232, thereby allowing the fourth slider 3232 to slide back and forth within the opening 3237 in a direction parallel to the longitudinal direction.

[0190]

[0210] Here, the second group of body length sensing elements 3203(i) extends into the space between the second wall 3204 and the third wall 3230 through a suitable opening in the second wall 3204. The body length sensing element 3203(i) is provided with a projection 3227 that extends into an inner slot 3229 of the third slider 3228. Here, the slot 3229 is straight and extends at an angle of 0 < α6 < 90 degrees with respect to the longitudinal direction.

[0191]

[0211] The third wire portion 16(i, 3) also extends into the space between the second wall 3204 and the third wall 3230 through a suitable opening in the second wall 3204. The third control wire portion 16(i, 3) is provided with a projection 3236 that extends into the inner slot 3234 of the fourth slider 3232. Here, the slot 3216 is straight and extends at an angle of 0 < α8 < 90 degrees with respect to the transverse direction.

[0192]

[0212] The second control wire portion 16(i, 2) also extends into the space between the second wall 3204 and the third wall 3230 through a suitable opening in the third wall 3230, such that the second and third control wire portions 16(i, 2) and 16(i, 3) extend in opposite directions from the length compensation section 3200. The second control wire portion 16(i, 2) is provided with a projection 3240 that extends into an inner slot 3238 of the fourth slider 3232. Here, the slot 3238 is straight and extends at an angle of 0 < α7 < 90 degrees with respect to the transverse direction.

[0193]

[0213] The second group of sensing elements 3203(i) and 3203(i+1) sense the length change La2 of the main body section 1303b. This change must be fully compensated such that Lr2 + Lr3 = La2. The first group of sensing elements 3201(i) and 3201(i+1) sense the length change of the main body section 1303a in addition to the length change of the main body section 1303b. The length change of the main body section 1303b is already compensated by the mechanism attached to the second group of sensing elements 3203(i) and 3203(i+1), and therefore does not need to be compensated any further by the mechanism attached to the first group of sensing elements 3201(i) and 3201(i+1). The only compensation that this mechanism must generate is a certain amount of overcompensation that, in addition to the compensation for the main body section 1303a, forces the tip section 1301 into a bending configuration in the same direction as the bending in the main body section 1303a. Therefore, Lr1 + Lr4 = La1 - La2 + overcompensation.

[0194]

[0214] This embodiment may be useful when advancing an instrument through a curved channel as shown in Figures 38A and 38B. While advancing through a gently curved section of the channel, there is no problem if the tip section 1301 of the instrument remains straight, which is achieved by length compensation sections attached to the second group of sensing elements 3203(i), 3203(i+1). When the tip section 1301 must pass through a tightly curved section of the channel, it is advantageous if the tip section 1301 is automatically steered in the direction of the curve. This can be achieved by compensation sections attached to the first group of sensing elements 3201(i), 3201(i+1), in which the length compensation unit, so to speak, overcompensates and steers the tip section in the direction of the curve sensed by the first group of sensing elements 3201(i), 3201(i+1). It can also be anticipated that three or more groups of sensing wires and corresponding length compensation sections may be used. Furthermore, each group may have three or more sensing elements, and similarly, there may be three or more control wires.

[0195]

[0215] Furthermore, within the scope of the present invention, it can be anticipated that two or more groups of control wires may be used, and that the input signals of one set of body length sensing wires may be used to compensate for the lengths of two sets of control wires, so that two controllable end sections can be controlled independently of each other. See Figure 39.

[0196]

[0216] Figure 39 comprises all the elements of Figure 34. Furthermore, the embodiment of Figure 39 includes the same section for a second control wire 16(i+1), which is also divided into two separate longitudinally extending portions.

[0197]

[0217] A first portion 16(i+1, 1) of the second control wire also extends into the space between the first wall 3202 and the second wall 3204 through a suitable opening in the first wall 3202. The first portion 16(i+1, 1) is provided with a projection 3248 extending into an inner slot 3246 of the third slider 3244. Here, the slot 3246 is straight and extends at an angle of 0 < α9 < 90 degrees with respect to the transverse direction. The third slider 3244 is positioned inside the first slider 3218 such that it is movable longitudinally inside the first slider 3218 independently of the first slider 3218, but is movable transversely only together with the first slider 3218.

[0198]

[0218] The second portion 16(i+1, 2) of the second control wire also extends into the space between the first wall 3202 and the second wall 3204 through a suitable opening in the second wall 3204, such that the first and second portions 16(i+1, 1) and 16(i+1, 2) extend in opposite directions from the length compensation section 3200. The second portion 16(i+1, 2) is provided with a projection 3252 that extends into a slot 3250 inside the second slider 3219. Here, the slot 3250 is straight and extends at an angle α10 with respect to the transverse direction.

[0199]

[0219] The mechanism operates similarly for both control wires 16(i) and 16(i+1) at this time, and no further clarification is needed here.

[0200]

[0220] This is applicable to all embodiments of Figures 32, 35, and 37, just as the mechanism in Figure 34 is replicated by two or more control wires 16(i) in the embodiment of Figure 39.

[0201]

[0221] A practical problem may arise when long instruments are packaged in a hoop. Packaging long instruments in a rolled circular form results in a more compact and easy-to-handle packing box shape rather than a very long, small, thin box. The problem with rolling up instruments is that the displacement of the body length sensing element can become very large, and in practice, considerably larger than the displacement generated during normal use of the instrument. To prevent the sensing element from breaking or buckling during rolling, the compensation mechanism must be able to handle large length changes. In fact, this can be a problem because it limits the allowable sliding capacity of sliders 3218 (and 3228). Another approach is to absorb the length change of the body length sensing element in another way, as shown in Figure 40.

[0202]

[0222] Figure 40 shows an embodiment that is almost identical to that shown in Figure 34. The difference is that in this case, the slot 3212 is provided with end slot portions that extend longitudinally at both ends.

[0203]

[0223] The same principle can, of course, be applied to all other illustrated and described embodiments.

[0204]

[0224] In this way, an excessive length change of the body length sensing element is possible without increasing the transverse displacement H to an impracticable magnitude. The compromise is that when the longitudinal displacement La is reached, further displacement of the body length sensing element will no longer compensate the steering wire, and as a result, the tip section can no longer be kept straight. This is not a problem if the packaging hoop tube has a diameter large enough to accommodate the bent tip.

[0205]

[0225] In the above examples of Figure 32 to Figure 40, the mechanism is presented on a flat plane. However, this mechanism can also be applied in a tubular form. In a tubular instrument, the longitudinal movement is in a direction equal to the longitudinal axis of the instrument, the transverse movement is equal to the tangential or rotational direction around the longitudinal axis of the instrument, and the movement perpendicular to the plane of the drawings is at this time radial, that is, perpendicular to the longitudinal axis of the instrument.

[0206]

[0226] The mechanism as described with reference to Figure 32 to Figure 40 can be applied to all steerable instrument embodiments of Figure 1 to Figure 31, including those that can be steered by manual operation or by a robotic steering device.

[0207]

[0227] When it is desired to apply the mechanism as presented in the previously shown Figure 32 to Figure 40 to a tubular instrument, and when the body length sensing element and the steering wire are within the same tubular wall, the following matters must be kept in mind. If the body length sensing element is at a circumferential location in the tubular wall different from that of the steering wire, there is a difference in the displacement that the body length sensing wire undergoes when the instrument body is bent, and in the length compensation that the steering wire needs to keep the instrument tip straight. Reference is made to Figure 41A, in which the steering wire 16(i) and the sensing wire 3201 are depicted as being within the same tube but positioned at different tangential locations.

[0208]

[0228] For example, as shown in Figure 41A, when the body length sensing element 3201 is located 90 degrees away from the circumferential location of the control wire 16(i), and the body is curved in a plane passing through the location of the control wire 16(i), the end of the body length sensing element 3201 is not displaced because its curved length does not change. However, the control wire 16(i) requires length compensation L to keep its tip straight. In this case, the mechanism does not function correctly. In practice, when the body length sensing element 3201 is right next to the control wire, the difference in displacement of the end of the body length sensing element is approximately equal to the length required by the compensating control wire 16(i), and in practice, this difference is not significant in the performance of the device.

[0209]

[0229] However, this problem can be overcome when the body length sensing element is used to activate the first slider 3218, which displaces a second slider 3219 having a reversal slot that compensates for the length of the control wire 16(i) at a circumferential location exactly 180 degrees different from the location of the body length sensing element 3201.

[0210]

[0230] Another solution is to position the body length sensing element 3201 and the control wire in different tube layers, as shown in Figure 41B. In this case, differences still exist in the length variation of the body length sensing element 3201 and the compensation required by the control wire 16(i), depending on their radial locations relative to each other. For example, when the control wire is above the body length sensing element in the radial direction, the control wire 16(i) requires length compensation greater than the length variation of the body length sensing element 3201. This can be easily compensated by adjusting the inclination angle of the slot in the mechanism such that there exists a fixed ratio between La and Lr that is equal to the ratio between the bending radii of the sensing element 3201 and the control wire 16(i).

[0211]

[0231] Figures 42A to 42H show one embodiment of a length compensation section at the proximal end of a tubular maneuverable instrument, in which all components are formed by creating a suitable slotted pattern within several coaxially arranged tubes and attaching some of the resulting components to other components in another adjacent tube, for example by (laser) welding, bonding, etc.

[0212]

[0232] Figure 42A shows the first tube 4202 through which the main body length sensing element and control wire are cut, and Figures 42B, 42C, 42D, and 42E show the second, third, fourth, and fifth tubes 4204, 4206, 4208, and 4210, respectively, placed on top of each other in the following order in the final assembled state.

[0213]

[0233] Figure 42A shows two of the four control wires 16(1) and 16(2) in total. At the proximal end of the device, the first tube 4202 comprises four body length sensing elements 3201(1) to 3202(4) that can be seen as two of them. In the example of Figure 42A, adjacent sensing elements 3201(i) are in contact with each other along at least a portion of their length at the proximal end. Each sensing element 3201(i) has a smaller (smaller width) sensing element portion that extends toward the distal end between two adjacent control wires 16(i) and 16(i+1). At their distal ends, these smaller sensing element portions are attached to a bendable or flexible section where bending causes an undesirable change in the length of one or more control wires 16(i) (see Figure 36).

[0214]

[0234] Figure 42B shows the second tube 4204 above the first tube 4202. This figure shows a first control wire attachment 4212(1), for example, welded, attached to the end of the control wire 16(1) in the first tube 4202 at one or more attachment locations 4214(1). This also shows a sensing element attachment 4220(1), for example, welded, attached to the end of the body length sensing element 3201(1) in the first tube 4202 at one or more attachment locations 4222(1). This also shows a “fixed world” tubular member 4205 having a first opening 4216(1) for linearly guiding the first control wire attachment 4212(1) in the longitudinal direction and a second opening 4218(1) for linearly guiding the body length sensing element attachment 4220(1) in the longitudinal direction.

[0215]

[0235] The second tube 4204 also includes a first control wire attachment section 4212(i) attached to the control wire 16(i) and located inside the opening 4216(i) for all other control wires 16(i). These functions are the same as those of the first control wire attachment section 4212(1). Furthermore, the second tube 2404 includes a sensing element attachment section 4220(i) attached to each sensing element 3201(i) and located inside the opening 4218(i) for all sensing elements 3201(i). These functions are the same as those of the sensing element attachment section 4220(1).

[0216]

[0236] Figure 42C shows a "fixed world" cylinder 4206(1) of a third tube 4206, for example, welded to a "fixed world" tubular member 4205 of a second tube 4204 at one or more mounting locations 4207. The second control wire attachment 4224(i) is located inside an opening 4226(i) configured to guide the second control wire attachment 4224(i) longitudinally. All second control wire attachments 4224(i) are attached to the first control wire attachment 4212(i) in the second tube 4204 at one or more mounting locations 4228(i), for example by welding.

[0217]

[0237] The figure also shows first and second length-compensating starter cylinders 4206(2) and 4206(4), which may be separated by the shorter cylinder 4206(3). Their functions are the same as those of slider 3218 in Figures 32–40. They can rotate freely around the second tube 4204 as indicated by arrows C and D. One starter cylinder is located in the left-right plane and one cylinder in the upper-lower plane of the flexible body.

[0218]

[0238] The first length-compensated start cylinder 4206(2) is provided with two slots 4234 extending at opposite angles (greater than 0 degrees but less than 90 degrees) with respect to the circumferential direction. Projections (not visible in Figure 42C) are provided inside each slot 4234 and are attached to the end of the sensing element mounting section 4220(i). These projections are comparable, for example, to the projection 3206 inside the first slider 3218 in Figure 32. The second length-compensated start cylinder 4206(4) is provided with two slots 4236 extending at opposite angles (greater than 0 degrees but less than 90 degrees) with respect to the circumferential direction. A projection 4238(i), one of which is indicated by reference numeral 4238(1), is provided inside each slot 4236. The projection 4238(1) is attached to the end of the sensing element mounting section 4220(1). These protrusions 4238(i) are also comparable to, for example, the inner protrusion 3206 of the first slider 3218 in Figure 32.

[0219]

[0239] Therefore, Figure 42C shows how two opposing sensing elements 3201(2), 3201(4) are connected to one “first” slider 4206(2), and two other opposing sensing elements 3201(1), 3201(3) (rotated 90 degrees relative to the two first mentioned) are connected to one other “first” slider 4206(4).

[0220]

[0240] The rotation of the first and second length-compensating starter cylinders 4206(2) and 4206(4) is initiated by projections 4238(i), that is, they operate like cam followers. As the main body length-sensing element 3201(i) moves longitudinally, each cam follower forces its respective cylinder to rotate a reference projection 3206 in a slot 3212 within the slider 3218.

[0221]

[0241] Figure 42D shows the fourth tube 4208 above the third tube 4206. The fourth tube 4208 comprises a “fixed-world” cylinder 4208(1) with one opening 4240(i) for each control wire 16(i). A third control wire attachment 4242(i) is positioned inside each opening 4240(i) and is attached to a second control wire attachment 4228(i) in the third tube 4206. The openings 4240(i) are configured to guide the third control wire attachment 4242(i) linearly in the longitudinal direction. The fixed-world cylinder 4208(1) is attached to the fixed-world cylinder 4206(1) at one or more attachment locations 4241, 4250.

[0222]

[0242] The fourth tube 4208 also comprises a cylinder 4208(2) having two longitudinally extending strips 4248 positioned rotated 180 degrees tangentially to each other and acting as linear guide strips. The linear guide strips 4248 are attached to the length compensating cylinder 4206(2) (acting as sliders 3218) and are welded, for example, to the length compensating cylinder 4206(2) so that they can rotate together with the length compensating cylinder 4206(2). Between these two longitudinally extending strips 4248, the fourth tube 4208 comprises two length compensating sliders 4208(3) (acting as sliders 3219) positioned rotated 180 degrees tangentially to each other. Each length compensating slider 4208(2) comprises two slots 4254, 4256 oriented at opposite angles with respect to the circumferential direction (these slots are comparable to the slots 3214, 3216 in the embodiment of Figure 34). These slots 4254, 4256 accommodate the respective protrusions (not visible in Figure 42D, but comparable to the protrusions 3208, 3210) attached to the respective control wire sections (such as 16(i, 1) and 16(i, 2) in Figure 34). See Figure 42E for an example of how this can be implemented. The strip 4248 prevents the length compensation slider 4208(3) from moving tangentially / circumferentially when the length compensation cylinders 4206(2) do not rotate and guide them longitudinally. Therefore, when the length compensation cylinders 4206(2) rotate due to the longitudinal displacement of the main body length sensing element 3201(i), the length compensation slider 4208(3) (such as slider 3219) is forced to move longitudinally.

[0223]

[0243] The fourth tube 4208 also comprises a cylinder 4208(5) having two longitudinally extending strips 4265, 4267 positioned rotated 180 degrees tangentially with respect to each other and acting as linear guide strips. The linear guide strips 4265, 4267 are attached to, for example, the length compensating cylinder 4206(2) (acting as sliders 3218) by welding, so that they can rotate together with the length compensating cylinder 4206(4). Between these two longitudinally extending strips 4265, 4267, the fourth tube 4208 comprises two length compensating sliders 4208(4) (acting as sliders 3219) positioned rotated 180 degrees tangentially with respect to each other. Each length-compensating slider 4208(4) has two slots 4258, 4260 oriented at opposite angles with respect to the circumferential direction (these slots correspond to slots 3214, 3216 in the embodiment of Figure 34). These slots 4258, 4260 accommodate respective projections 4262, 4264 (corresponding to projections 3208, 3210) attached to their respective control wire sections (such as 16(i, 1), 16(i, 2) in Figure 34). See Figure 42E for an example of how this can be implemented. Strips 4265, 4267 prevent the length-compensating sliders 4208(4) from moving tangentially / circumferentially when the length-compensating cylinders 4206(4) do not rotate and guide the length-compensating cylinders 4208(4) longitudinally. On the other hand, if the length compensation cylinder 4206(4) rotates due to the longitudinal displacement of the main body length sensing element 3201(i), the length compensation slider 4208(4) (such as slider 3219) is forced to move longitudinally.

[0224]

[0244] Figure 42E shows a fifth tube 4210. This fifth tube 4210 comprises a subsequent "fixed world" cylinder 4277 having a linear guide section 4278(i). Between two adjacent linear guide sections 4278(i), 4278(i+1), the fifth tube 4210 has a longitudinal opening 4268 that accommodates a first section 4270(i) (corresponding to 16(i,1)) and a second section 4274(i) (corresponding to 16(i,2) of the control wire 16(i)). The fixed world cylinder 4277 having the linear guide section 4278(i) is attached to the lower fixed world cylinder 4208(1) at one or more mounting locations 4276, 4280, for example by laser welding.

[0225]

[0245] The first control wire section 4270(i) (control wire section 16(i, 1)) can move only in the longitudinal direction, while the linear guide section 4278(i) prevents movement in the tangential / circumferential direction. The same applies to the second control wire section 4274(i) (control wire section 16(i, 2)).

[0226]

[0246] The first control wire portion 4270(i) is attached at its distal end to the third mounting slider 4242(i) at mounting location 4272, for example by laser welding. The first control wire portion 4270(i) is attached at its proximal end to the projection 4262 in slot 4258 at mounting location 4273. The second control wire portion 4274(i) is attached at its distal end to the projection 4264 in slot 4260 at mounting location 4275, for example by laser welding. Therefore, when the length compensation slider 4206(4) is forced to rotate by the longitudinal displacement of the main body length sensing element and the proximal control wire 16(i) is held in a fixed position, the linear guides 4265, 4267 also rotate together with the length compensation slider 4208(4), and the projections 4262, 4264 force the first control wire portion 4270(i) in the required longitudinal direction over the distance required for all length compensation of the control wire 16(i).

[0227]

[0247] FIGS. 42F to 42H show an embodiment in which the protrusions 4262 and 4264 are not applied, and are substituted by inwardly bent lips. Here, the first steering wire portion 4270(i) is provided with an inwardly bent lip 4282 in the slot 4258 at its proximal end. Further, the second steering wire portion 4274(i) is provided with an inwardly bent lip 4284 in the slot 4260 at its distal end. FIG. 42H shows the lip 4284 on an enlarged scale.

[0228]

[0248] It will be apparent to those skilled in the art how this mechanism operates for all four steering wires 16(i) of the embodiment of FIGS. 42A to 42H. Furthermore, the mechanism also operates for any other number of steering wires and any number of sensing elements, which numbers need not be equal.

[0229]

[0249] In fact, there is a final tubular element provided on the assembly shown in FIG. 42E that protects the mechanism and radially retains the first steering wire portion 4270(i) and the second (proximal) steering wire portion 4274(i) in place. This tubular element is not depicted. Furthermore, in practice, an inner protective tubular element is inserted into the first tube 4202.

[0230]

[0250] Clearly, the embodiments described above with reference to Figures 42A to 42H represent only one possible practical implementation of the basic mechanism proposed according to Figures 32 to 41B. Within the scope of the present invention, many more possible practical implementations can be considered. Devices can be constructed having fewer or more tubular elements than those described in this embodiment, and in which elements such as sliders, steering wires, and sensing wires are located within different tubular elements than those described in the embodiment. Naturally, within the scope of the present invention, it can also be envisioned that devices can be constructed in which the steering wires are located above the main length sensing element, or vice versa, in different tubular elements. Furthermore, devices can be envisioned having two or more length-compensating sliders (sliders 3218), as shown in Figure 35, with separate steering wire bridge elements connecting these sliders. Also, tubular devices can be envisioned having two or more groups of main length sensing elements, each having its own length-compensating mechanism, as shown in Figure 36. Furthermore, as shown in Figure 39, a device may be conceivable in which a mechanism having two or more controllable sections within the tip of the device and one body length sensing wire input can simultaneously compensate for the lengths of two or more sets of control wires. In addition, other combinations of different embodiments of the mechanism are possible, as shown in Figures 32 to 41B, for example, a device may be conceivable in which two sets of body length sensing wires, as shown in Figure 37, are combined with two sets of control wires, as shown in Figure 39. [Crushing element]

[0251] In the controllable devices described above, crushing elements are applied during manufacturing. Examples of crushing elements and methods in which they may be used during manufacturing are first described in detail in the applicant's International Publication No. 2016 / 089202.

[0231]

[0252] Typically, such a crushing element may be designed in the following way, as described here with reference to, for example, crushing element 1629(j): The crushing elements are fabricated in the same process steps as other elements are cut from the tube. Before crushing, each crushing element is attached to opposing parts of two tube sections. In this way, they keep these two opposing parts together, preventing them from falling apart after the cutting process. These opposing parts have a geometric shape such that the stress within the crushing element increases during operation above the stress in the surrounding material and / or structure. Thus, if a deflection or sufficiently large force is applied to the two opposing parts that attempts to move the two opposing parts relative to each other, the stress within the crushing element rises above the yield stress of the tube material, causing permanent deflection of the crushing element. As a result of applying even greater deflection or a greater force, the stress reaches the maximum tensile stress of the crushing element, and since the stress accumulated within the two parts remains below its yield stress, it causes the crushing element to break without causing permanent deformation of the two parts.

[0232]

[0253] In this way, the tubing elements, which must be independently movable relative to one another within the final maneuverable device, can be separated while different tubes are inserted into each other, and the elements cannot be further separated. That is, the crushing process is preferably carried out when the maneuverable device is finished, all the tubes are inserted into each other, and the elements that must be attached to each other are attached.

[0233]

[0254] This is schematically shown in Figures 43, 44, and 45. Figure 43 shows a crushing element 4306 attached to the first tube portion 4302 and the second tube portion 4304 of the tube 4300. Here, the crushing element 4306 has the form of a small disc attached to the first tube portion 4302 and the second tube portion 4304 via a small bridge. In Figure 43, the first tube portion 4302 and the second tube portion 4304 can move relative to each other in the longitudinal direction of the tube 4300. The bridge of the crushing element 4306 to the opposing first portion 4302 and second portion 4304 will crush when they move relative to each other and the above stress condition is applied.

[0234]

[0255] Figure 44 shows an embodiment having two opposing first tube sections 4302 and second tube sections 4304 that remain attached to each other during assembly by a small bridge-shaped crushing element 4306. In this embodiment, the opposing first tube section 4302 and second tube section 4304 can rotate relative to each other within the surface of the figure indicated by arrow 4402. As they rotate relative to each other, forces accumulate inside the crushing element 4306 and inside the surrounding material of the opposing tube sections 4302 and 4304 until the stress inside the crushing element 4306 rises above the maximum tensile stress, causing the temporary crushing element 4306 to break.

[0235]

[0256] Figure 45 shows an alternative to the one shown in Figure 44, in which the first tube portion 4302 and the second tube portion 4304 can rotate relative to each other as indicated by arrow 4502. In this configuration, the crushing element 4306 has the shape of a small disc attached to the two opposing tube portions 4302, 4304 by a small bridge. In this embodiment, these bridges will crush under the stress conditions described above.

[0236]

[0257] Figures 43, 44, and 45 illustrate the application of a crushing element 4306 between two opposing tube sections 4302, 4304 that can move longitudinally relative to each other or rotate relative to each other. However, since these crushing elements 4306 will eventually be crushed by sufficient movement during use, these crushing elements can be used anywhere in a maneuverable device between two opposing tube sections that move relative to each other in the use of a maneuverable device, whether rotationally, longitudinally, radially, or tangentially. Other mechanisms for fracturing the fracturing element 4306 may be achieved by subjecting the fracturing element to low or high cycle fatigue. The stress within the fracturing element is raised above the fatigue limit, causing fatigue fracturing. It should be noted that this fatigue limit is less than the maximum tensile stress mentioned above. In all cases, the stress in the structure / material around the two opposing tube elements to which the fracturing element 4306 is attached remains at least below the yield stress of the tube material. The fracturing process by subjecting it to several fatigue cycles is preferably carried out when the maneuverable equipment is finished, all the tubes are inserted into each other, and the elements that must be attached to each other are installed.

[0237]

[0258] Figures 46 to 49 show alternative structures for the crushing element, namely the melting element.

[0238]

[0259] Figure 46 shows an example of a molten element having a larger section 4606 attached to a second tubular section 4304 and a smaller bridge 4604 attached to a first tubular section 4306 after a cutting process. Here, the first tubular section 4302 and the second tubular section 4304 are intended to rotate relative to each other during normal use of a maneuverable instrument. At this time, the molten element 4604 / 4606 is irradiated with an energy beam, such as a laser beam, so that it melts and the molten material of the larger section 4606 attaches the second tubular element 4304 to the tubular section of the inner tube of the illustrated tube. Simultaneously, the attachment between the first tubular section 4302 and the second tubular section 4304 is released as the smaller bridge 4604 of the molten element is disconnected.

[0239]

[0260] Figure 46 shows an embodiment in which the molten element has a larger, rounded portion 4606 attached to the second tubular portion 4304, while Figure 47 shows an embodiment in which the larger portion 4606 has a rectangular shape. Other shapes are possible without departing from the concept of the present invention.

[0240]

[0261] Figures 48 and 49 show a molten element having only the smaller bridges 4604(1), 4604(2), 4604 with different possible shapes. Other shapes may also be applied. To release the attachment between the first tube element 4302 and the second tube element 4304, an energy beam, such as a laser beam, is again directed towards the smaller bridges 4604(1), 4604(2), 4604, so that they evaporate.

[0241]

[0262] Figures 46–49 show the application of the molten elements 4604 / 4606 between two opposing tube sections 4302, 4304 intended to rotate relative to each other during use, but these can be used anywhere in a maneuverable instrument between two opposing tube sections that move relative to each other in the use of the maneuverable instrument, whether rotationally, longitudinally, radially, or tangentially.

[0242]

[0263] It has also been observed that the molten element may be designed to release the attachment between the two tube sections by applying several steps, namely a first step in which the molten element is partially evaporated and a second step in which the remaining part of the molten element is crushed by either the crushing process described above or a process that involves several crushing cycles.

[0243]

[0264] The melting process is performed at any appropriate time during the manufacture of the maneuverable instrument, provided that the molten elements can be reached by an energy beam, for example, through a suitable opening in the surrounding tube.

[0244]

[0265] The crushing and melting elements described with reference to Figures 43 to 49 may be applied to any of the tubes of any of the maneuverable devices described with reference to Figures 1 to 42. [General Overview]

[0266] The material removal means may be a laser beam or a water jet cutting beam that melts and vaporizes the material, and this beam may have a width between 0.01 and 2.00 mm, more typically between 0.015 and 0.04 mm for this application. Therefore, the slots between adjacent portions of the tube may have a minimum width between 0.01 and 2.00 mm, more specifically between 0.015 and 0.04 mm.

[0245]

[0267] The wall thickness of the tube depends on its application. For medical applications, the wall thickness may be in the range of 0.03 to 2.0 mm, preferably 0.03 to 1.0 mm, more preferably 0.05 to 0.5 mm, and most preferably 0.08 to 0.4 mm. The diameter of the tube depends on its application. For medical applications, the diameter may be in the range of 0.5 to 20 mm, preferably 0.5 to 10 mm, and more preferably 0.5 to 6 mm. The radial clearance between adjacent tubes may be in the range of 0.01 to 0.3 mm.

[0246]

[0268] A longitudinal element within one tube and other elements within an adjacent tube can be attached to other longitudinal elements within the adjacent tube, thereby enabling these elements to work together to transmit longitudinal motion from a steering wire at the proximal end of the instrument to the bendable portion of the instrument at the distal end, so that the bendable portion bends. This is described in detail in the applicant's International Publication No. 2017 / 213491 (see, for example, Figures 12, 13a, and 13b in that PCT application).

[0247]

[0269] It will be apparent to those skilled in the art that the scope of the present invention is not limited to the examples discussed above, and that several amendments and modifications are possible without departing from the scope of the invention as defined in the appended claims. While the present invention has been shown and described in detail in the drawings and description, such drawings and description are not restrictive and are considered illustrative or exemplary only. The present invention is not limited to the disclosed embodiments and comprises any combination of disclosed embodiments that may lead to advantages.

[0248]

[0270] Modifications to the disclosed embodiments may be understood and brought about by those skilled in the art in carrying out the claimed invention, by considering the figures, description, and appended claims. In the description and claims, the term “equipped with” does not exclude other elements, and the indefinite article “a” or “an” does not exclude plural. In fact, this is to be interpreted as meaning “at least one.” The mere fact that certain features are described in mutually different dependent claims does not indicate that a combination of these features cannot be used advantageously. No reference numeral in the claims should be construed as limiting the scope of the invention. The features of the embodiments and aspects described above can be combined, provided that the combination does not create an obvious technical conflict.

Claims

1. A cylindrical instrument comprising at least a first tube (1601; 1619), a second tube (1620) surrounding the first tube (1601; 1619), and a third tube (1602; 1621) surrounding the second tube (1620), wherein the cylindrical instrument has at least one deflectable tip section (1613), a steering section (1618), a flexible body section (1615) between the tip section (1613) and the steering section (1618), a length compensation section (1617), and one or more steering wires (16(i)) extending from the steering section (1618) to the tip section (1613), wherein the tip section (1613) can be deflected by moving the one or more steering wires (16(i)) in the longitudinal direction of the cylindrical instrument. A cylindrical device comprising a first portion of a control wire (16(i)) at least partially surrounded by a control wire guide portion, wherein both the control wire (16(i)) and the associated control wire guide portion are part of at least one of the first tube (1619), the second tube (1620), or the third tube (1621), and each first portion of the control wire (16(i)) and the associated control wire guide portion is configured as a length-compensating element having a curved configuration configured to deform to absorb the change in length of the second portion of the control wire (16(i)) inside the flexible body section (1615) due to the bending of the flexible body section (1615).

2. The cylindrical device according to claim 1, wherein the curved configuration is at least one of the following: extending radially outward from the central axis (1622), extending radially inward toward the central axis (1622), extending tangentially with respect to the central axis (1622), or being helical around the central axis of the cylindrical device.

3. The cylindrical device according to claim 1 or 2, wherein the control wire guide portion comprises at least one longitudinal guide element length compensation portion (1620a(2,i), 1620b(2,i)) aligned with the first portion of each control wire (16(i)), and the at least one longitudinal guide element length compensation portion (1620a(2,i), 1620b(2,i)) is the same portion of at least one of the first tube (1619), the second tube (1620), or the third tube (1621), of which the control wire (16(i)) is a part.

4. The cylindrical device according to claim 3, wherein the at least one longitudinal guide element length compensation portion (1620a(2,i), 1620b(2,i)) comprises two longitudinal guide element length compensation portions (1620a(2,i), 1620b(2,i)) along different sides of the first portion of each steering wire (16(i)).

5. The cylindrical device according to claim 1 or 2, wherein the length compensation section (1617) comprises a control wire guide portion associated with one control wire (16(i)) including an inner control wire guide portion (1619(2,i)) which is part of the first tube (1619) and an outer control wire guide portion (1621(2,i)) which is part of the third tube (1621).

6. The cylindrical device according to claim 5, wherein the length compensation section (1617) comprises one or more radially oriented lips (1623) located tangentially adjacent to the control wire (16(i)) and attached to at least one of the inner control wire guide portion (1619(2,i)) or the outer control wire guide portion (1621(2,i)).

7. The cylindrical device according to claim 5, wherein the length compensation section (1617) comprises one or more island portions (1625(j)) slidably disposed within the at least one control wire (16(i)) so as to limit the tangential movement of the at least one control wire (16(i)).

8. A cylindrical device according to claim 1 or 2, comprising a square element (1645) having a first bar (1645(1)) and a second bar (1645(2)) both extending in a first direction, and a third bar (1645(3)) and a fourth bar (1645(4)) both extending in a second direction perpendicular to the first direction, wherein the first and second bars (1645(1), 1645(2)) are slidably connected to the vertices of opposing sets of one control wire and associated control wire guide portions within the length compensation section (1617), and the third and fourth bars (1645(3), 1645(4)) are slidably connected to the vertices of other opposing sets of control wires and associated control wire guide portions within the length compensation section (1617).

9. A cylindrical device according to claim 1 or 2, wherein a portion of one control wire (16(i)) is located in one of the first, second, and third tubes (1619, 1620, 1621) in at least two different sections from the at least one deflectable tip section (1613), the control section (1618), the flexible body section (1615), and the length compensation section (1617).

Images