Patent Description:
Surgical apparatuses used in surgery have different structures depending on the location of a surgical site and how the surgical site will be treated. In recent years, various types of surgical equipment using a robot are being developed to perform surgery on areas where surgical sites are difficult to access by existing surgical apparatuses or to perform a minimal invasive surgery. These surgical apparatuses are configured to move in various directions in the human body by including a bendable element, which are disclosed in many documents including <CIT>. <CIT> and <CIT> disclose further steerable surgical apparatuses.

Surgical apparatuses bendable at the distal end bend by the movement of wires inside them. However, these surgical apparatuses are hard to finely manipulate, revealing some problems like creating backlash when they are bent with the wires or restricting the movement of other wires. Also, these surgical apparatuses have many components embedded in them which are connected to one another in a complicated way, so it is difficult to miniaturize them.

The invention is described in the appended claims.

Hereinafter, a surgical apparatus according to exemplary embodiments will be described concretely with reference to the drawings. A description of the positional relationship between the components will now be made basically with reference to the drawings. In the drawings, structures of the embodiments may be simplified or exaggerated for clarity.

The exemplary embodiments will be described with respect to a surgical apparatus that has a plurality of passages inside an insertion part, with various kinds of surgical instruments located in each passage. Exemplary embodiments of the invention as defined in the appended claims are described in conjunction with <FIG>. Other figures that are described herein illustrate additional components or provide further context for the invention.

Hereinafter, a surgical apparatus according to an exemplary embodiment will be described concretely with reference to the drawings. A description of the positional relationship between the components will now be made basically with reference to the drawings. In the drawings, structures in the embodiment may be simplified or exaggerated for clarity.

This exemplary embodiment will be described with respect to a surgical apparatus that has a plurality of passages inside an insertion part, with various kinds of surgical instruments located in each passage.

<FIG> is a view illustrating a surgical apparatus according to an exemplary embodiment. As illustrated in <FIG>, a surgical apparatus <NUM> comprises an insertion part <NUM> provided at the distal end of the surgical apparatus and a manipulating part <NUM> located at the proximal end of the insertion part <NUM>.

The insertion part <NUM> forms a part that is inserted into a surgical site during surgery. The insertion part <NUM> consists of a flexible tube, in which at least one surgical instrument <NUM> for use in a surgical operation is located. The surgical instrument <NUM> may be selectively located in at least one hollow passage that is formed inside the insertion part <NUM>. Alternatively, the surgical instrument <NUM> may be embedded in the insertion part <NUM>. The surgical instrument <NUM>, sticking out of the distal end of the insertion part <NUM>, may be used in surgery or capture images of the surgical site.

The surgical apparatus of <FIG> comprises an insertion part <NUM> with four passages, each passage including four surgical instruments <NUM>. In <FIG>, two out of the four surgical instruments include forceps <NUM> as end effectors <NUM> at the distal end. Such surgical instruments may perform various surgical operations by manipulating the forceps. Besides, other various types of surgical elements including blades, suturing units, needles, etc. can be used. One of the remaining two surgical instruments is an imaging unit <NUM>. The imaging unit <NUM> may capture images of the distal end by including an optical device such as an optical fiber. The other surgical instrument may be a lumen unit <NUM> with a working channel in it through which various instruments can be inserted.

These surgical instruments <NUM>, sticking out of the distal end of the insertion part <NUM>, are configured such that their protruding end can bend. Accordingly, the bending of the surgical instruments <NUM> allows for performing a surgical operation in different directions or taking images from different directions. The surgical instruments <NUM> may bend by the movement of a plurality of wires inside them, which will be described in detail below.

The manipulating part <NUM> is provided at the proximal end of the insertion part <NUM>, and configured to manipulate the insertion part <NUM> and/or the surgical instruments <NUM>. The distal end of the manipulating part <NUM> is connected to the proximal end of the insertion part <NUM>, and may be detachably connected thereto in this exemplary embodiment. At least one driving part is provided in the manipulating part <NUM>. The driving part <NUM> is mechanically connected to the insertion part <NUM> and/or various types of wire members of the surgical instruments <NUM>, and the driving part <NUM> enables various motions of the insertion part <NUM> and/or surgical instruments <NUM>, including bending movement of the surgical instruments <NUM>.

Hereinafter, a detailed configuration of the above-described surgical apparatus will be explained in more detail with reference to the drawings.

<FIG> is a cross-sectional view of one of the surgical instruments of <FIG>. As illustrated in <FIG>, the surgical instrument <NUM> comprises a steerable member <NUM> at the distal end that is bendable. The steerable member <NUM> has a plurality of bending segments <NUM> with hollow channels (not shown) that are connected together. A flexible member <NUM> comprising a flexible material is provided at the proximal end of the steerable member <NUM>. The flexible member <NUM> may consist of a hollow tube where various types of wire members connected from the distal end of the surgical instrument <NUM> are located. Optionally, an end effector <NUM> is provided at the distal end of the steerable member <NUM>, and the end effector <NUM> may be selectively actuated by an effector actuation wire <NUM>.

Each bending segment <NUM> of the steerable member <NUM> is connected to adjacent bending segments in a way that allows hinge movement, and bent by means of bending actuation wires <NUM>. The bending actuation wires <NUM> are located in such a way as to pass through the steerable member <NUM> and the flexible member <NUM>, and the distal ends of the bending actuation wires <NUM> are connected to the steerable member <NUM> and their proximal ends are mechanically connected to the manipulating part <NUM>. Each bending segment <NUM> comprises a plurality of lumens <NUM> that are formed lengthwise, and the bending actuation wires <NUM> are located within the lumens <NUM> (<FIG>). Accordingly, when the bending actuation wires <NUM> are moved by the manipulating part <NUM>, the plurality of bending segments <NUM> move hingedly, thus causing the steerable member <NUM> to bend.

<FIG> is a view schematically illustrating a slack in a wire due to bending of the steerable member. Let the bending segments <NUM> have a length of L and a width of 2r. Adjacent bending segments <NUM> are hinged at the middle on their facing sides (which is at a distance of r from the outer perimeter). Let the bending actuation wires <NUM> be located on two opposite sides of the width of each bending segment and pass through the middle of the length of each bending segment (which is at a distance of L from each hinged portion).

<FIG> illustrates the steerable member before bending, and <FIG> illustrates the steerable member when bent to a radius of curvature R. In <FIG>, the angle of bend between two bending segments <NUM> is denoted by θ. The following equation is to compare the sum of the lengths of two wire portions between the two bending segments before bending and the sum of the lengths of the two wire portions after bending. If the lengths of the two wire portions before bending are denoted by L<NUM> and L<NUM>, respectively, and the lengths of the two wire portions after bending are denoted by L<NUM>' and L<NUM>', respectively, the difference ΔL between the two lengths is as follows: <MAT> <MAT> <MAT>.

As seen from above, the sum of the lengths of the two wire portions between the two bending segments after bending is smaller than that before bending. Accordingly, when the wires on both sides are manipulated in conjunction with each other, a slack of ΔL is produced between each bending segment. This is because, when bending occurs, the amount of change (L<NUM>'-L<NUM>) in the length of the wire on the other side of the center of curvature is smaller than the amount of change (L<NUM>-L<NUM>') in the length of the wire near the center of curvature. Accordingly, backlash is created due to bending, thus making fine adjustment difficult.

In contrast, in this exemplary embodiment, the bending segments may be configured in various shapes to minimize the slack caused by bending. <FIG> is a view schematically illustrating a slack in a wire according to an improved bending segment structure. As illustrated in <FIG>, the improved bending segments <NUM> are configured in such a way that part of the lumens <NUM> where the bending actuation wires are located is open (see <FIG>). Herein, t denotes the length of an open lumen portion. While the wire near the center of curvature has the shorter path due to the open lumen portion, the wire on the other side of the center of curvature has the path to which an extra length is added at the corresponding open lumen portion. In this case, the path L<NUM>* of the wire near the center of curvature is equal in length to the previous path (L<NUM>' of <FIG>), and the path L<NUM>* of the wire on the other side of the center of curvature is longer than the previous path (L<NUM>' of <FIG>). This increase in path length is because a sidewall of the open lumen portion (near the center of the bending segments) on the other side of the center of curvature forms a stumbling portion <NUM> and the bending actuation wire <NUM> passing through the path stumbles against the stumbling portion <NUM> (see <FIG>). Accordingly, when bending occurs using the improved bending segments, ΔL is as follows: <MAT> <MAT> <MAT> <MAT>.

As stated above, with the improved bending segments <NUM> configured to reduce the length ΔL of the slack, the movement of the surgical apparatus <NUM> can be finely controlled. Generally, the length t of the open lumen portions may be <NUM>% or more of the length L of the bending segments. Although the amount of reduction in the length ΔL of the slack differs depending on the dimension, angle of bend, etc. of the bending segments, the length ΔL of the slack may be reduced by approximately <NUM> % or more.

The improved bending segments may be designed in various ways. Hereinafter, various exemplary embodiments of the bending segments will be described in detail with reference to <FIG>.

<FIG> is a view illustrating a structure of bending segments with <NUM> degree of freedom. The bending segments <NUM> shown in <FIG> have a body with hollow channels <NUM> formed within them. One pair of connecting parts <NUM> is provided on one end of the length of the body and other one pair of connecting parts <NUM> is provided on the opposite end. Each pair of connecting parts <NUM> is located facing each other on two opposite sides of the width of the body, with a hollow channel <NUM> midway between them.

Each bending segment <NUM> is hinged to adjacent bending segments, and connected to them by the connecting parts coupled to those of the adjacent ones. In <FIG>, the connecting parts <NUM> are connected by pinning them together. As hinge shafts of the connecting parts <NUM> all have the same orientation, the steerable member of <FIG> has <NUM> degree of freedom at which it bends to the left or right (as shown in the drawing).

Each bending segment <NUM> includes a pair of lumens <NUM> in which the bending actuation wires are located. The pair of lumens <NUM> may be formed by penetrating through the wall surface of a hollow body, and they are arranged symmetrically about the center of a cross-section of the bending segment <NUM>, spaced a predetermined distance from each other.

As shown in <FIG>, the lumens of the bending segments <NUM> are partially open. Specifically, each lumen comprises a closed lumen portion 112b and an open lumen portion 112a. In the closed lumen portion 112b, the inner and outer sides are enclosed by wall surfaces as shown in <FIG>, so that the bending actuation wire moves only within the lumen due to the sidewall structure. In contrast, in the open lumen portion 112a, at least part of its sidewalls has an open structure. Accordingly, the bending actuation wire located in the open lumen portion 112a is movable outside the lumen through the open portion.

In this exemplary embodiment, the open lumen portion 112a has a structure in which a sidewall 113a on the outer side of the bending segment (which is on the opposite side of the center of a cross-section of the bending segment) is open. Accordingly, when bending occurs, the wire 400a near the center of curvature moves to an open portion (outward direction) of the open lumen portion, which enables the bending segments to be connected on a shorter length, as compared with the closed lumen portion. On the contrary, a sidewall 113b of the open lumen portion (near the center of the cross-section of the bending segment), if located on the other side of the center of curvature, forms a stumbling portion <NUM> against which a wire stumbles. Accordingly, when bending occurs, the wire 400b on the other side of the center of curvature is brought into more contact with the bending segment as it stumbles against the stumbling portion <NUM>, thereby reducing the length of the slack.

In <FIG>, each lumen <NUM> of the bending segments <NUM> is configured in such a way that a closed lumen portion 112b is formed at the middle of the lumen length and an open lumen portion 112a is located on either side of the closed lumen portion 112b. This is merely an example, and one side of the lumen <NUM> along the length may form an open lumen portion and the other side may form a closed lumen portion. Alternatively, the open lumen portions of a pair of adjacent bending segments may be arranged symmetrically with respect to the hinge shafts. In this way, the lumens where the bending actuation wires are located may be variously altered in such a way that a wall surface (inner wall surface) 113b near the center of a cross-section of the bending segments is longer than a wall surface (outer wall surface) 113a on the other side of the center of the cross-section thereof.

Although <FIG> illustrates that the open lumen portion 112a is longer than the closed lumen portion 112b. It should be noted that the length of the open lumen portion occupying <NUM>% or more of the entire lumen length may be advantageous to reducing the length of the slack.

The connecting parts of the bending segments can be formed in various ways, other than pinning the connecting parts together as shown in <FIG>. <FIG> illustrates an example of a different type of connecting parts.

The bending segments of <FIG> each include a pair of connecting part <NUM> on one side and a pair of recess parts <NUM> on the other side. The connecting parts <NUM> of a bending segment <NUM> are accommodated in the recess parts <NUM> of an adjacent bending segment and hinged to them. The connecting parts <NUM> of A of <FIG> each consist of a protrusion with a round surface, and the recess parts <NUM> each are configured to accommodate the protrusion. Accordingly, each connecting part <NUM> moves hingedly as it rotates within the corresponding recess part <NUM>. The connecting parts <NUM> of B of <FIG> each consist of a protrusion with a linear edge at the end, and the recess parts <NUM> each have a v-shaped notch-like groove. Accordingly, the connecting parts <NUM> can move hingedly as the area of contact with the recess parts <NUM> rotates about the axis of rotation, while they are in linear contact with the recess parts <NUM>.

<FIG> is a view illustrating a structure of bending segments with <NUM> degrees of freedom. The bending segments of <FIG> each are connected to adjacent bending segments in a way that allows hinge movement, and configured in such a way that a hinge shaft h1 connected to a bending segment on one side and a hinge shaft h2 connected to a bending segment on the other side have different orientations. Accordingly, the bending segments <NUM> of <FIG> constitute a steerable member that is movable at <NUM> or more degrees of freedom, unlike in <FIG> and <FIG>.

Specifically, each bending segment <NUM> of <FIG> includes a pair of connecting parts <NUM> on one side of the length and a pair of recess parts <NUM> on the other side. The pair of connecting parts <NUM> face each other with respect to the center of the bending segment <NUM>, and the pair of recess parts <NUM> also do likewise. As is the case in <FIG>, the connecting parts <NUM> each consist of a protrusion with a round surface, and the recess parts <NUM> are configured to be rotatable and accommodate the connecting parts.

As illustrated in <FIG>, in each bending segment <NUM>, a shaft that joins the pair of connecting parts <NUM> and a shaft that runs between the pair of recess parts <NUM> are orthogonal to each other. That is, the pair of connecting parts and the pair of recess parts are positioned at different locations with respect to a cross-section of the bending segment <NUM> (more specifically, the pair of connecting parts and the pair of recess parts intersect at <NUM> degrees around the body).

Hence, the bending segment <NUM> moves hingedly with respect to an adjacent segment on one side on a first shaft h1 and with respect to an adjacent segment on the other side on a second shaft h2. That is, the connecting parts of the bending segments are configured in such a way that the first hinge shaft and the second hinge shaft are arranged in an alternating fashion. Accordingly, the bending segments of <FIG> may move at <NUM> degrees of freedom.

Each bending segment comprises four lumens that are formed along the length. As illustrated in <FIG>, each lumen <NUM> is arranged to penetrate a connecting part <NUM> or a recess part <NUM>. Accordingly, the four lumens are positioned at locations where the connecting parts and the recess parts are formed, spaced at <NUM>-degree intervals around the body.

Four bending actuation wires <NUM> are located in the four lumens <NUM>, respectively. Among them, one pair of wires induces bending of one shaft of the steerable member, and the other pair of wires induces bending of the other shaft.

Each lumen is partially open, as is with the aforementioned example. As illustrated in <FIG>, a portion of each lumen <NUM> along the length where a connecting part <NUM> or recess part <NUM> is formed forms a closed lumen portion 112b, and the other portion where the connecting part <NUM> or recess part <NUM> is not formed forms an open lumen portion 112a. Needlessly to say, the closed lumen portion may be centered on each lumen, and the open lumen portion may be positioned on either side of the closed lumen portion. Nevertheless, the configuration shown in <FIG> offers the advantage of further reducing the length of the slack.

Besides, although <FIG> illustrates that the lumen <NUM> penetrates the connecting part <NUM> or recess part <NUM>, the lumen <NUM> may be diverted from the connecting part <NUM> and the recess part <NUM>. Specifically, the connecting parts <NUM> and the recess parts <NUM> may be spaced at <NUM>-degree intervals around the lateral side of the body (e.g., along the circumference) of the bending segment <NUM>. Each lumen <NUM> may be located between the connecting part <NUM> and the recess part <NUM>, especially at a point where it is at <NUM> degrees to the connecting part <NUM> and the recess part <NUM>.

In this case, as illustrated in <FIG>, each lumen <NUM> may be configured in such a way that a closed lumen portion 112b is formed at the middle of the length of the lumen and an open lumen portion 112a is formed on either side of the closed lumen portion 112b.

<FIG> and <FIG> have been explained with respect to a connecting part <NUM> consisting of a protrusion with a round surface and a recess part <NUM> accommodating the connecting part <NUM>. However, this is merely an example, and as shown in B of <FIG>, the connecting part may consist of a protrusion with a linear edge and the recess part may have a v-shaped notch-like groove (see <FIG>). Otherwise, as shown in <FIG>, two connecting parts may be pinned together in a way that allows hinge movement, rather than each comprising the connecting part and the recess part.

The exemplary embodiments shown in <FIG> involve a connecting structure for rotation with respect to one shaft, in which a pair of connecting parts is provided at one bending segment and a pair of recess parts is provided at another bending segment. Besides, one connecting part and one recess part may be located on one end of one bending segment to face each other with a hollow body between them, and the connecting part and recess part of an adjacent bending segment may be located the other way round, taking into account the layout of the connecting part and recess part of the bending segment connected to the adjacent bending segment.

<FIG> is a view illustrating a steerable member using a flexible hinge structure. As illustrated in <FIG>, the bending segments <NUM> are in the shape of a disc-like plate, and connected by flexible connecting parts <NUM> situated between the bending segments <NUM>. While the steerable member of <FIG> can be bent using a mechanical hinge structure of the connecting parts, the steerable member of <FIG> can be bent using the elasticity of the material of the connecting parts.

More specifically, the steerable member of <FIG> consists of a plurality of bending segments <NUM> formed integrally with one another and a plurality of connecting parts <NUM>. For example, it may be manufactured by a molding method using plastic resin with flexibility. As illustrated in <FIG>, each bending segment <NUM> and each connecting part <NUM> have a hollow channel <NUM> inside them. The connecting parts <NUM> are provided between each bending segment <NUM>, and have a wall structure that extends in an outer radial direction from two opposite sides of the hollow channel. A connecting part <NUM> (wall structure) is arranged in a direction perpendicular to the direction in which an adjacent connecting part is arranged. Accordingly, the steerable member of <FIG> may bend at <NUM> degrees of freedom.

Four lumens <NUM> where bending actuation wires <NUM> are located are arranged at <NUM>-degree intervals. Each lumen <NUM> is formed at a point where it penetrates the outer edge of a connecting part <NUM>. In this instance, as in the foregoing exemplary embodiment, each lumen <NUM> is a partially open lumen portion <NUM>. As illustrated in <FIG>, the closed lumen portion 112b of each lumen is formed at a point where it penetrates the connecting part and the open lumen portion 112a thereof is formed on either side of the closed lumen portion 112b where the bending segment is penetrated. Accordingly, the steerable member <NUM> of this exemplary embodiment may bend on the connecting parts <NUM> as the bending actuation wires <NUM> move.

<FIG> is a view illustrating a steerable member using a flexible backbone structure. The steerable member <NUM> of <FIG> comprises bending segments <NUM> each consisting of a disc-like plate and connecting parts <NUM> using a backbone structure for connecting the centers of the bending segments. The connecting parts <NUM> may consist of individual members provided between each bending segment, or may consist of a single member that penetrates through a plurality of bending segments. In this case, the connecting parts <NUM> may comprise a flexible material, and may bend when the bending actuation wires <NUM> move.

The steerable member of <FIG> also includes four lumens <NUM>, and each lumen is partially open. Specifically, the lumen <NUM> may include a closed lumen portion 112b formed at the middle part of the length of the lumen and an open lumen portion 112a formed on either side of the closed lumen portion 112b.

In the exemplary embodiments set forth above, bending segments capable of minimizing slack are used to prevent backlash caused by bending. The steerable member may be configured in other various ways in order to prevent backlash.

<FIG> are views illustrating a steerable member with a lateral supporting member <NUM>. The lateral supporting member <NUM> comprises an elastic material or super-elastic material, and exerts a restoration force for returning to the original shape when its shape is deformed. That is, this steerable member may include at least one lateral supporting member within it, and may be configured to restore the elasticity of the lateral supporting member to the initial position when it is bent.

<FIG> is a view illustrating bending properties provided by a lateral supporting member. As illustrated in <FIG>, if at least one bending actuation wire <NUM> is pulled by manipulating the manipulating part, the steerable member <NUM> bends in the corresponding direction. In this case, the steerable member <NUM> comprises at least one lateral supporting member <NUM>, and the bending actuation wire <NUM> is manipulated to cause bending by overcoming the elasticity of the lateral supporting member <NUM> (B of <FIG>). Afterwards, when the corresponding bending actuation wire is released from being pulled (C of <FIG>), the steerable member <NUM> returns to neutral by the elasticity of the lateral supporting member <NUM>.

Conventionally, while the bending actuation wire on one side is manipulated to bend in one direction, the bending actuation wire on the other side is manipulated to return to neutral. Accordingly, a slack occurs due to the bending, causing backlash. However, with the use of the lateral supporting member as shown in <FIG>, the backlash caused by the slack in the bending actuation wire may not be a problem during the bending.

<FIG> is a view illustrating various exemplary embodiments of a steerable member using lateral supporting members. As illustrated in <FIG>, the steerable member <NUM> may comprise a plurality of bending actuation wires <NUM> and a plurality of lateral supporting members <NUM>. The lateral supporting members <NUM> may be configured in various types of structures, such as a wire structure or a hollow tube structure, that can function as lateral springs. The bending segments <NUM> of the steerable member <NUM> are configured to bend at <NUM> degrees of freedom, and may comprise a plurality of lumens <NUM> for allowing the bending actuation wires <NUM> and the lateral supporting members <NUM> to pass through them along the wall surface of the body.

In A to C of <FIG>, a plurality of bending actuation wires <NUM> and a plurality of lateral supporting members <NUM> are placed separately. In A and B of <FIG>, four bending actuation wires <NUM> are arranged at <NUM>-degree intervals around the body of the bending segments <NUM>, and four lateral supporting members <NUM> are arranged at <NUM>-degree intervals between each bending actuation wire <NUM>. In this case, as shown in A of <FIG>, the four bending actuation wires <NUM> may be arranged to pass through the connecting parts <NUM> of the bending segments, and as shown in B of <FIG>, the four lateral supporting members <NUM> may be arranged to pass through the connecting parts <NUM> of the bending segments <NUM>. Alternatively, as shown in C of <FIG>, a bending actuation wire <NUM> and a lateral supporting member <NUM> may be arranged as a pair between each connecting part location along the circumference, so as not to pass through the connecting parts of the bending segments <NUM>.

In D and E of <FIG>, the lateral supporting members <NUM> have a hollow tube structure, and the bending actuation wires <NUM> are located inside the lateral supporting members <NUM>, respectively. The lateral supporting members <NUM> and the bending actuation wires <NUM> may be arranged at <NUM>-degree intervals around the body of the bending segments <NUM>. In D of <FIG>, the lateral supporting members <NUM> and the bending actuation wires <NUM> are arranged to pass through the connecting parts of the bending segments. In E of <FIG>, the lateral supporting members <NUM> and the bending actuation wires <NUM> are located between each connecting part location so as not to pass through the connecting parts.

<FIG> is a view illustrating bending properties provided by a pre-shaped lateral supporting member. The lateral supporting members of <FIG> and <FIG> have a shape corresponding to the neutral position of the steerable member. Accordingly, the steerable member is configured to be bent with the bending actuation wires and to return to neutral by the lateral supporting members. In contrast, the lateral supporting member <NUM> of <FIG> is configured to have a bent shape in one direction so that the elasticity of the lateral supporting member <NUM> contributes to bending of the steerable member to one side.

In an example, the lateral supporting member <NUM> of <FIG> is pre-shaped to bend to the left. The steerable member with the lateral supporting member <NUM> in it remains bent to the left without any manipulation using the bending actuation wire (A of <FIG>). Also, if the bending actuation wire <NUM> moves by a first tensile force F, the steerable member can be placed in the neutral position (B of <FIG>). The first tensile force is large enough to be in equilibrium with a moment created by the elasticity of the lateral supporting member <NUM>. If the bending actuation wire <NUM> moves by a second tensile force F', which is larger than the first tensile force, the steerable member can bend to the right (C of <FIG>). In this case, if the tensile force exerted on the bending actuation wire <NUM> is released by the first tensile force, the steerable member can move to neutral (B of <FIG>), or if the tensile force exerted on the bending actuation wires is completely released, the steerable member can bend to the left (A of <FIG>).

In this instance, the steerable member moves to the neutral position or the initial position by the elasticity of the lateral supporting member, thereby enabling bending control without backlash. Although <FIG> depicts a bending mechanism that has <NUM> degree of freedom using a pre-shaped lateral supporting member and bending actuation wires, a variety of bending mechanisms using a pre-shaped lateral supporting member may be used.

In addition, a bending mechanism using connecting segments that causes no backlash, as well as the above-mentioned method using a lateral supporting member, may be used, as shown in <FIG>.

<FIG> is a view illustrating a wire path difference caused by bending of bending segments connected by connecting segments. In the foregoing exemplary embodiment (e.g., in <FIG>), each bending segment <NUM> may be coupled directly to adjacent bending segments by the connecting parts <NUM> provided in the body, and rotate relative to one hinge shaft shared between each pair of adjacent bending segments. In contrast, as shown in <FIG>, a connecting segment <NUM> is provided between each pair of adjacent bending segments <NUM>, and two adjacent bending segments are connected to two ends of the connecting segment <NUM>, respectively. The connecting segment <NUM> has a double hinge joint structure that enables two points on the connecting segment <NUM> to be hinged to two different members. Accordingly, a pair of adjacent bending segments <NUM> is coupled to two ends of the connecting segments, respectively, so as to rotate relative to different hinge shafts, without sharing a hinge shaft.

Let the distance between the wires on either side of a bending segment <NUM> be 2r and let the distance between two hinge shafts of the connecting segment be L. The bending segment <NUM> may be hinged to the connecting segment <NUM>, at a point midway between a pair of wires (i.e., at a distance of r from each wire).

A of <FIG> illustrates the adjacent bending segment before bending, and B of <FIG> illustrates the adjacent bending segment when bent to a radius of curvature R. In B of <FIG>, the angle of bend between two bending segments <NUM> is denoted by θ. Also, it can be assumed that the angles θprox and θdistal of bend between the bending segments and the connecting segment created by bending are equal. In this case, the following equation is to compare the sum of the lengths of two wire portions between the two bending segments before bending and the sum of the lengths of the two wire portions after bending. The lengths of the two wire portions before bending are denoted by L<NUM> and L<NUM>, respectively, and the lengths of the two wire portions after bending are denoted by L<NUM>' and L<NUM>', respectively. <MAT> <MAT> <MAT> <MAT> <MAT> <MAT> <MAT>.

That is, if the steerable member <NUM> connected by the connecting segment <NUM> is bent, the sum (L<NUM>+L<NUM>) of the lengths of the two wire portions before bending and the sum (L<NUM>'+L<NUM>') of the lengths of the two wire portions after bending are substantially equal. Accordingly, any slack caused by bending can be prevented.

Needless to say, <FIG> assumes that the angles θprox and θdistal of bend between the bending segments <NUM> and the connecting segment <NUM> are equal because bending occurs at each bending segment due to the same wire. However, when actual bending occurs, the angles of bend between the connecting segment <NUM> and the bending segments <NUM> are within a substantially similar range although they are slightly different. Thus, the length of slack can be minimized as compared to the structure in which two bending segments are coupled together on a single hinge shaft.

<FIG> is a perspective view illustrating a connecting segment and bending segments connected by the connecting segment. <FIG> is a perspective view illustrating a steerable member comprising connecting segments.

As illustrated in <FIG>, a connecting segment <NUM> is hinged to a first bending segment 110a and a second bending segment 110b at different points. The connecting segment <NUM> comprises two bodies <NUM> facing each other. Each body <NUM> includes a first hinge part 142a on one end of its length and a second hinge part 142b on the other end. The first and second bending segments 110a and 110b are coupled to the first and second hinge parts 142a and 142b, respectively, so that they move hingedly on different hinge shafts.

In <FIG>, the first hinge part 142a and the second hinge part 142b each consist of a protrusion with a round surface, and are accommodated in recess parts 121b formed in the bending segments <NUM> and move hingedly. However, this is merely an example, and at least one of the first and second hinge parts may be a recess part for accommodating the protrusion or may be connected by other hinge structures such as pinning.

The connecting segment <NUM> further comprises a guide member <NUM> with a hollow space inside it that joins together the two bodies <NUM> facing each other. Due to this, the connecting segment <NUM> may form a module. The hollow space of the guide member <NUM> allows various kinds of wire members such as the bending actuation wires or the effector actuation wire to pass through, and prevents internal components from falling out during bending. A cross-section of the guide member <NUM> may be similar to a cross-section of the bending segments. In this case, portions through which the bending actuation wires pass may be open so as not to restrict the movement of the bending actuation wires.

The steerable member of <FIG> comprises a plurality of connecting segments <NUM>, and adjacent connecting segments <NUM> are configured to have hinge shafts orthogonal to each other. Each bending segment <NUM> has four lumens <NUM> so that four bending actuation wires <NUM> are respectively located in them. Therefore, the steerable member <NUM> can bend at <NUM> degrees of freedom. In this case, the bending actuation wires <NUM> may be located between each hinge shaft location around the body of the bending segments <NUM> so as not to pass through the hinge shafts of the connecting segments <NUM>.

In another exemplary embodiment, <FIG> is a view schematically illustrating a slack in a wire that forms a curved path due to bending of the steerable member. While <FIG> depicts a wire that forms a bent straight-line path when bending occurs, <FIG> depicts a wire that forms a curved path when bending occurs. If the lengths of two wire portions before bending are denoted by L1 and L2, respectively, and the lengths of the two wire portions after bending are denoted by L1' and L2', respectively, the relationship between the lengths of the two wire portions is as follows: <MAT> <MAT> <MAT> <MAT>.

As compared with the wire of <FIG> that forms a bent straight-line path when bending occurs, the wire of <FIG> that forms a curved path can have an approximately <NUM>% reduction in the length of the slack. Using this principle, the bending actuation wires are configured to form a curved path when bending occurs by including a path adjusting member, thereby minimizing the slack.

<FIG> is a view illustrating a steerable member using a path adjusting member. As illustrated in <FIG>, the steerable member <NUM> comprises plate-like bending segments <NUM> and wall-like connecting parts <NUM> located between the bending segments. Also, four lumens <NUM> are formed to penetrate the outer edges of the bending segments <NUM> and connecting parts <NUM> (refer to the description of <FIG>).

As illustrated in B of <FIG>, bending actuation wires <NUM> are located inside the path adjusting member <NUM> in each lumen, rather than being located directly in each lumen. The path adjusting member <NUM> comprises an elastic material such as metal, and bends when the steerable member <NUM> is bent, thereby forming a curved wire path (in this case, the elasticity of the path adjusting member does not need to be high enough to produce a restoration force as shown in D and E of <FIG>, and an elastic force sufficient to form a curved path will do). Accordingly, the bending actuation wires <NUM> according to this exemplary embodiment bend not along a bent straight-line path but along a curved path, thereby minimizing the length of the slack.

While this exemplary embodiment has been described with respect to an example in which the path adjusting member is used for the steerable member using a flexible hinge structure, modifications may be made, like placing wires in the steerable member shown in <FIG> with the use of the path adjusting member.

<FIG> is a view illustrating bending of the steerable member. As illustrated in <FIG>, at the initial stage of the bending, the bending is not uniform across the entire steerable member <NUM>, but it is concentrated at the distal end of the steerable member where the bending actuation wire <NUM> ends (see B of <FIG>). Thus, a force is transmitted directly to the distal end of the steerable member when the wire moves, causing the steerable member to bend less at the proximal end.

<FIG> is a cross-sectional view of a steerable member according to one exemplary embodiment. A, B, and C of <FIG> depict an embodiment for improving the concentration of bending at the distal end of the steerable member, which involves a geometrically enhanced structure in which the steerable member bends more easily at the distal end than at the proximal end.

Specifically, as shown in A of <FIG>, the bending segments <NUM> have lumens formed at a distance from the center of a cross-section of the steerable member, and the closer to the proximal end of the steerable member, the more distant the lumens in the bending segments get from the center of the cross-section of the steerable member. In this case, the moment applied to the steerable member <NUM> is smaller at the distal end and increases towards the proximal end. Thus, the steerable member <NUM> bends more easily toward the proximal end.

In B of <FIG>, the connecting parts <NUM> may be configured to gradually change in shape along the length of the steerable member <NUM> such that the steerable member bends more easily at the proximal end than at the distal end. In an example, as illustrated in B of <FIG>, the bending properties along the length can be adjusted by configuring the connecting parts to have a larger sectional width at the distal end than at the proximal end. Alternatively, apart from adjusting the width of the connecting parts, the connecting parts may be configured in other various ways of shape variation, including adjusting the range of movement of connecting parts having a joint structure.

Also, as shown in C of <FIG>, the distance between the bending segments <NUM> may change along the length. Specifically, the connecting parts <NUM> may be positioned such that the distance between the bending segments gets shorter toward the distal end and longer toward the proximal end. In this case, the longer the distance between the bending segments, the easier the bending of the steerable member. This results in restriction of the bending near the distal end and improvement in the bending properties near the proximal end.

The steerable member of this configuration has a plurality of bending actuation wires located along the lumens, and the distal end of each bending actuation wire is fixed by a wire termination member <NUM> provided at the distal end of the steerable member.

<FIG> is a view illustrating a method of fixing bending actuation wires by a wire termination member. As the steerable member and the bending actuation wires are very small in size, fixing individual bending actuation wires to the distal end of the steerable member is highly difficult. Accordingly, this exemplary embodiment uses a wire termination member capable of easily fixing a plurality of bending actuation wires.

As illustrated in <FIG>, the wire termination member <NUM> has a thread <NUM> on one side, and is screwed to the distal end of the steerable member <NUM>. Also, the wire termination member includes a plurality of holes <NUM> through which a plurality of bending actuation wires pass, and the holes <NUM> are formed at locations corresponding to the lumens in the steerable member. Accordingly, as shown in <FIG>, the wire termination member can be screwed to the distal end of the steerable member while the bending actuation wires <NUM> are inserted in the holes of the wire termination member (A of <FIG>), thereby making it easy to fix the bending actuation wires (B and C of <FIG>).

The wire termination member may be a component that is provided between the steerable member and the end effector. In this case, the wire termination member may be screwed to the distal end of the steerable member, and the end effector may be connected to the wire termination member. Alternatively, as illustrated in <FIG>, the end effector <NUM> may be used as the wire termination member by fixing the bending actuation wires <NUM> to the inside of the end effector <NUM> and screwing the end effector <NUM> directly to the distal end of the steerable member <NUM>.

Although <FIG> has been described with respect to a steerable member having the structure shown in <FIG>, it is needless to say that the bending actuation wires can be likewise fixed even if the steerable member has other structures.

In the above discussion, various exemplary embodiments of the steerable member have been described with reference to <FIG>. The steerable member is described as a component of the surgical apparatus that has an end effector.

Referring back to <FIG>, the end effector <NUM> is provided at the distal end of the steerable member. As described above, the end effector <NUM> may be coupled directly to the distal end of the steerable member <NUM> or coupled to it through a component such as the wire termination member. The end effector <NUM> comprises various types of surgical elements <NUM> for use in surgery. <FIG> illustrates an end effector comprising a forceps by way of example.

The proximal end of the end effector <NUM> is connected to the effector actuation wire <NUM>. The effector actuation wire <NUM> is located in the channels <NUM> of the steerable member <NUM>, and mechanically connected to the manipulating part <NUM> through the steerable member <NUM> and the flexible member <NUM>. Accordingly, the effector actuation wire <NUM> actuates the end effector <NUM> as it moves lengthwise by the manipulating part <NUM>.

<FIG> is a cross-sectional view schematically illustrating the operating principle of the end effector. The end effector <NUM> operates in a first mode when the effector actuation wire <NUM> is pulled in the direction of the manipulating part <NUM> (A of <FIG>), and operates in a second mode when the effector actuation wire <NUM> is pulled in the direction of the end effector <NUM> (B of <FIG>). The first mode involves closing the forceps of the end effector, and the second mode involves opening the forceps. The action of pulling the effector actuation wire <NUM> in the direction of the manipulating part may be done easily by the driving part of the manipulating part, thereby transmitting the force to the end effector. On the other hand, the action of bringing the effector actuation wire <NUM> back in the direction of the end effector <NUM> may not be done properly by the driving part <NUM> because the effector actuation wire has a wire structure. Accordingly, in this exemplary embodiment, the end effector <NUM> may include an elastic body <NUM> to perform a second mode operation by pulling the effector actuation wire <NUM> using the elasticity of the elastic body <NUM>.

Specifically, as illustrated in <FIG>, an effector module of the end effector comprises an instrument portion <NUM> for performing a surgical operation and an actuation portion <NUM> for actuating the instrument portion <NUM>. The instrument portion <NUM> is linked to the actuation portion <NUM>, and configured such that the surgical elements <NUM> are opened or closed on both sides by the movement of the actuation portion <NUM> while a joint <NUM> of the instrument portion <NUM> is fixed. The elastic body <NUM> may be located at the proximal end of the actuation portion. When the effector actuation wire <NUM> is pulled by the manipulating part <NUM>, the actuation portion <NUM> moves backward while pushing the elastic body <NUM> and the surgical elements <NUM> are therefore closed (A of <FIG>). Also, when the force acting on the effector actuation wire <NUM> is released by the manipulating part <NUM>, the restoration force of the elastic body <NUM> causes the actuation portion <NUM> to move in the direction of the instrument portion <NUM>, thereby opening the surgical elements <NUM> (B of <FIG>). In this way, the operative mechanism of the end effector can be simplified with the use of the elastic body.

The structure of the end effector using the elastic body may be designed in various ways. <FIG> is a view illustrating an example of such an end effector. As illustrated in <FIG>, the end effector <NUM> may comprise an effector module <NUM> and a body portion <NUM> where the effector module <NUM> is mounted. The instrument portion <NUM> of the effector module <NUM> is configured to be exposed to the distal end of the body portion <NUM>, and the actuation portion <NUM> thereof is accommodated inside the body portion <NUM>. A joint <NUM> connecting the instrument portion <NUM> and the actuation portion <NUM> may be fixed at the body portion <NUM>, and the actuation portion <NUM> may reciprocate inside the body portion <NUM>. The elastic body <NUM> provided inside the body portion <NUM> is located behind the actuation portion <NUM>, and the proximal end of the actuation portion <NUM> is connected to the effector actuation wire <NUM>. Accordingly, the instrument portion <NUM> may be manipulated by moving the actuation portion <NUM> with the effector actuation wire <NUM> and the elastic body <NUM>.

Also, all or part of the end effector <NUM> may be detachably connected to the distal end of the steerable member <NUM>. Accordingly, a variety of instruments needed for surgery may be selectively fastened and used. In an example, the end effector <NUM> of <FIG> is configured such that the effector module <NUM> is attachable to or detachable from the distal end of the effector actuation wire <NUM>. The effector module <NUM> and the distal end of the effector actuation wire <NUM> may be detachably fastened in various ways; for example, they may be magnetically fastened together according to the exemplary embodiment illustrated in <FIG>. Accordingly, at least either the proximal end of the actuation portion <NUM> or the distal end of the effector actuation wire <NUM> consists of a magnetic body, which enables the fastening.

As described above, a surgical instrument according to this exemplary embodiment comprises a bendable steerable member <NUM> and an operable end effector <NUM>. Also, the steerable member <NUM> and the end effector <NUM> are moved by a plurality of wire members such as the bending actuation wires <NUM> and the effector actuation wire <NUM>. These wire members are arranged to pass through the steerable member <NUM> and the flexible member <NUM>. Accordingly, if the wire members are linearly arranged so that each of them has the shortest path, the movement of the wires may be restricted or affected by the bending of the steerable member or flexing of the flexible member. Therefore, in this exemplary embodiment, at least one sleeve forming a path of travel of a wire member may be provided inside the steerable member or the flexible member. This sleeve is longer than the maximum length of the portion where the sleeve is provided (for example, the length of that portion when bent or flexed), so the wire members have a long enough path even when the steerable member is bent or the flexible member is flexed.

<FIG> is a cross-sectional view illustrating a path of travel of the effector actuation wire. As illustrated in <FIG>, one end of the effector actuation wire <NUM> is mounted at the proximal end of the end effector <NUM>, and the other end is mechanically connected to the manipulating part <NUM> (<FIG>). One end of a sleeve <NUM> forming a path of the effector actuation wire <NUM> is fixed in place at the distal end of the steerable member <NUM> or the proximal end of the end effector <NUM>. Also, the other end is fixed in place at the proximal end of the flexible member <NUM>. In this instance, the sleeve <NUM> is longer than the length of the portion where two ends of the sleeve are fixed (the sum of the length of the steerable member and the length of the flexible member). This extra length added to the sleeve (A of <FIG>) gives more room for the path of the effector actuation wire <NUM> even when the steerable member <NUM> is bent (B of <FIG>). Accordingly, the movement of the end effector <NUM> may be decoupled from the bending movement of the steerable member <NUM> to prevent its movement from being affected by the bending movement of the steerable member <NUM>.

<FIG> is a view illustrating a path of travel of the bending actuation wire. As illustrated in <FIG>, a sleeve <NUM> for securing the path of the bending actuation wire <NUM> may be provided. In this case, one end of the sleeve <NUM> is fixed at the proximal end of the steerable member <NUM> or the distal end of the flexible member <NUM>, and the other end is fixed at the proximal end of the flexible member <NUM>. The sleeve <NUM> is configured to have an extra length added to the linear length of the portion where the sleeve is placed. Accordingly, the bending of the steerable member <NUM> will not be affected by the flexing of the flexible member <NUM>.

<FIG> and <FIG> are views illustrating a path of travel of a bending actuation wire <NUM> with two bendable portions. While the previous drawings illustrate a structure in which the steerable member <NUM> has one bending portion, the steerable member <NUM> may be divided into a distal end steerable portion <NUM> and a proximal end of steerable portion <NUM>, which can bend separately. In this case, the distal end steerable portion <NUM> is bent with a distal end bending actuation wire <NUM>, and the proximal end steerable portion <NUM> is bent with a proximal end bending actuation wire <NUM>. One end of the distal end bending actuation wire <NUM> is fixed at the distal end of the distal end steerable portion <NUM>, passes through the lumens in the distal end steerable portion <NUM>, and then extends to the manipulating part <NUM> through hollow channels of the steerable member <NUM> and flexible member <NUM>. Also, one end of the proximal end bending actuation wire <NUM> is fixed at the distal end of the proximal end steerable portion <NUM>, passes through the lumens in the proximal end steerable portion <NUM>, and then extends to the manipulating part <NUM> through hollow channels of the flexible member <NUM>. In this instance, two distal end bending actuation wires <NUM> and two proximal end bending actuation wires <NUM> may be provided and have <NUM> degree of freedom in each bending portion, or four distal end bending actuation wires <NUM> and four proximal end bending actuation wires <NUM> may be provided and have <NUM> degrees of freedom in each bending portion.

As illustrated in <FIG>, a sleeve <NUM> for securing a path of the distal end bending actuation wire <NUM> may be provided. One end of this sleeve <NUM> may be fixed at the proximal end of the distal end steerable portion <NUM>, and the other end may be fixed at the proximal end of the flexible member <NUM>. Also, as illustrated in <FIG>, a sleeve <NUM> for securing a path of the proximal end bending actuation wire <NUM> may be provided. One end of this sleeve <NUM> may be fixed at the proximal end of the proximal end steerable portion <NUM>, and the other end may be fixed at the proximal end of the flexible member <NUM>. As is the case with the above-mentioned sleeves, each sleeve <NUM> has an extra length, so the bending movement of each bending portion can be decoupled.

As described above, the sleeves <NUM> explained with reference to <FIG> have an extra length added to the length of the portion where they are placed, and they may comprise an elastic material, allowing their shape to change along with the movement of the components. Such a sleeve structure allows decoupling of the movement of each component from the movement of the others, and prevents wire members in narrow channels from being twisted or damaged by friction.

<FIG> is a view illustrating a connecting structure of the end of a surgical instrument and the manipulating part. As explained above, the surgical instruments <NUM> are respectively located in passages in the insertion part <NUM>, and the end of a surgical instrument is mechanically connected to the manipulating part <NUM>. The manipulating part <NUM> comprises transmission members <NUM> corresponding to a plurality of wire members W of the surgical instrument and couplers <NUM> to be fastened to wires. The wire members W of the surgical instrument each include a proximal end module M at the proximal end, and each proximal end module M is fastened to the corresponding coupler <NUM>. Thus, each wire member can be moved by each driving part in the manipulating part.

In this case, the insertion part <NUM> and the manipulating part <NUM> are attachable to or detachable from each other, and the surgical instrument <NUM> provided in the insertion part <NUM>, too, is attachable to or detachable from the manipulating part <NUM>. This means that the insertion part or the surgical instrument can be cleaned or replaced with new ones. The surgical instrument <NUM> and the manipulating part <NUM> may be detachably fastened in various ways; for example, they may be magnetically fastened together, as shown in <FIG>. Accordingly, the proximal end of the surgical instrument (specifically, the proximal end modules of the bending actuation wires and effector actuation wire) or the distal end of the manipulating part (specifically, the couplers of the transmission members) may be consist of a magnetic body and be attached to or detached from each other by magnetic force.

<FIG> schematically illustrate the configuration of the manipulating part <NUM> for moving the bending actuation wires <NUM>. The wire members W of the above-described surgical instrument are mechanically connected to the driving part <NUM> of the manipulating part <NUM> and move linearly along with the movement of the driving part <NUM>. The driving part may be constructed using various devices such as an actuator, a linear motor, a motor, etc. Also, each wire member may be connected to different driving parts so that they can move separately.

In this instance, a pair of bending actuation wires <NUM> located facing each other within the steerable member <NUM> move in opposite directions when bending occurs. Specifically, when bending occurs, the bending actuation wire near the center of curvature has a shorter path and the bending actuation wire on the other side of the center of curvature has a longer path. Accordingly, the pair of wires facing each other may move simultaneously in opposite directions with the use of a single driving part <NUM>. In this case, the manipulating part can be designed to be compact by reducing the number of driving parts.

In <FIG>, the manipulating part comprises a screw member <NUM> and a driving part <NUM> for rotating the screw member <NUM>. The screw member <NUM> may be a bi-directional lead screw, which means that two thread portions having different orientations are formed on a single screw member. Accordingly, the coupler of a transmission member to be connected to a first bending actuation wire <NUM> is coupled to a first thread 41a, and the coupler of a transmission member to be connected to a second bending actuation wire <NUM> is coupled to a second thread 41b. Accordingly, as the driving part rotates, the first bending actuation wire <NUM> and the second bending actuation wire <NUM> move respectively a corresponding distance, in opposite directions on a straight line, thereby causing the steerable member to bend. Also, the directions of movement of the first bending actuation wire <NUM> and the second bending actuation wire <NUM> may be reversed by changing the direction of rotation of the driving part, thus enabling them to bend in the reverse direction.

In <FIG>, the manipulating part comprises a pair of screw members and a driving part <NUM> for rotating the screw members. The pair of screw members consists of a first lead screw <NUM> with a first thread and a second lead screw <NUM> with a second thread oriented in the opposite direction to the first thread. The first lead screw <NUM> and the second lead screw <NUM> are connected to the driving part <NUM> by a gear <NUM> and rotate in the same direction along with the rotation of the driving part. The first bending actuation wire <NUM> is mechanically connected to the first lead screw <NUM>, and the second bending actuation wire <NUM> is mechanically connected to the second lead screw <NUM>. Accordingly, as is the case in <FIG>, when the motor rotates, the first and second bending actuation wires may move in opposite directions, causing the steerable member to bend.

Although <FIG> depict the use of a screw member as an example to drive the bending actuation wires in a pair, it is needless to say that modifications can be made using various link structures.

<FIG> is a view schematically illustrating the length of a bending actuation wire before and after bending in an ideal continuous flexible arm. <FIG> shows the length of the bending actuation wire before bending in an ideal continuous flexible arm, while <FIG> shows the length of the bending actuation wire after bending in an ideal continuous flexible arm being pulled with a wire-driven mechanism A (e.g. a pulley).

In an ideal continuous flexible arm, let a bending actuation wire be located on two opposite sides of the wire-driven mechanism A having a width of 2r,wherein "r" indicates a radius of the wire-driven mechanism A; "L<NUM>" and "L<NUM>" respectively indicate the length of the bending actuation wire from both opposite sides of the wire-driven mechanism A to the bending segment (not shown) before bending; "L<NUM>'''and "L<NUM>'" respectively indicate the length of the bending actuation wire from both opposite sides of the wire-driven mechanism A to the bending segment (not shown) after bending; "L" indicates the length from the center of the wire-driven mechanism A to the bending segment; "R" indicates a radius of curvature when the wire-driven mechanism A is pulled as an arrow pointed to, and the angle of bend by the wire-driven mechanism A is denoted by "θ".

In the ideal continuous flexible arm shown in <FIG>, the total length of the bending actuation wire before and after bending can be represented as the following equation:.

However, as shown in <FIG> which is a view schematically illustrating the length of a bending actuation wire before (shown in <FIG> and after bending (shown in <FIG> in the actual condition. As <FIG> illustrated, the bending actuation wire is elongated by being pulled (indicated as ΔL elongation), resulting in slack B on the released wire, which causes backlash. In this condition, the total length of the length of the bending actuation wires before and after bending can be represented as the following equation:.

In contrast, in this exemplary embodiment, the bending segment may be configured to comprise a series of intermediate joints having tension-regulating members to minimize the slack caused by elongation. <FIG> is a view illustrating an exemplary bending segment according to an embodiment of the present invention. In <FIG>, the bending segment <NUM> is illustrated to include four intermediate joints <NUM>, <NUM>, <NUM>, <NUM> arranged along a longitudinal axis direction of the bending segment. Each intermediate joint <NUM>, <NUM>, <NUM>, <NUM> has a first link portion <NUM>, <NUM>, <NUM> and <NUM> and a second link portion <NUM>, <NUM>, <NUM> and <NUM>, respectively. Each intermediate joint <NUM>, <NUM>, <NUM>, <NUM> may be interstacked orthogonally, in parallel or in any angle with the adjacent intermediate joint.

The bending segment <NUM> further comprises a plurality of lumens <NUM> passing through each intermediate joint <NUM>, <NUM>, <NUM>, <NUM>. The same number of bending actuation wires (being omitted for clarity) may be thus correspondingly provided to be arranged to pass through each lumen <NUM> respectively and cause the bending segment <NUM> to bend.

Each intermediate joint <NUM>, <NUM>, <NUM>, <NUM> further comprises two tension-regulating member <NUM>, <NUM>, <NUM> and <NUM> coupled to the first link portion <NUM>, <NUM>, <NUM> and <NUM> and the second link portion <NUM>, <NUM>, <NUM> and <NUM>. Each tension-regulating member <NUM>, <NUM>, <NUM> and <NUM> is configured to compensate for the elongation of the bending actuation wires when bending segments bend, whereby the length of bending actuation wires is altered and kept in a predetermined length.

In <FIG>, the tension-regulating member <NUM> is a double-hinged joint comprising two off-axis hinge joints <NUM>. Each off-axis hinge joint <NUM> comprises a first interfacing half <NUM>, <NUM>' coupled to the first link portion <NUM> and a second interfacing half <NUM>, <NUM>' coupled to the second link portion <NUM> and correspondingly pivoted to the first interfacing half <NUM>, <NUM>'. In this embodiment, each first interfacing half <NUM>, <NUM>' may have a protrusion end, respectively, while the second interfacing half <NUM>, <NUM>' correspondingly may have a recess end. In another embodiment, each first interfacing half may respectively have a recess end instead, while the second interfacing half correspondingly has a protrusion end.

Pivotal motion will occur on one of the two off-axis hinges <NUM> depending on bending orientation. <FIG> illustrates pivotal motion of one of the tension-regulating member of <FIG>, wherein <FIG> is a front view of the tension-regulating member bending on the left side, and <FIG> is a front view of the tension-regulating member bending on the right side. As shown in <FIG>, the intermediate joint bends in a bending orientation on the left side on the left hinge <NUM> which is offset from the longitudinal axis direction, whereby only first interfacing half <NUM> pivotally moves on the left side. Similarly, only first interfacing half <NUM>' pivotally moves on the right side when intermediate joint <NUM> bends on the right side as shown in the <FIG>.

<FIG> is a view schematically illustrating a slack in a wire caused by wire elongation being minimized using the tension-regulating member structure in <FIG>. <FIG> shows the length of the bending actuation wire before the tension-regulating member structure bends, while <FIG> shows the length of the bending actuation wire after the tension-regulating member structure bends.

In <FIG> and <FIG>, "L" indicates respectively the height of the first link portion <NUM> or the second link portion <NUM> along a direction of the central axis of the intermediate joint <NUM>. "L<NUM>" indicates the length of a bending actuation wire which passes through the lumen between the left side of the first link portion <NUM> and the second link portion <NUM> before bending, while "L<NUM>'"indicates the length of the bending actuation wire in the left side after bending. "L<NUM>" indicates the length of a bending actuation wire which passes through the lumen between the right side of the first link portion <NUM> and the second link portion <NUM> before bending, while "L<NUM>'" indicates the length of the bending actuation wire in the right side after bending. "r" indicates a radius from the central axis of each link portion to the lumen that the bending actuation wire passes through. "R" indicates a radius of curvature when the intermediate joint <NUM> bends and the angle of bend is denoted by "θ". "d" herein indicates a distance from the central axis of each link portion to each off-axis hinge joints <NUM>.

As shown in <FIG> and <FIG>, if wire elongation is ignored in this embodiment, the total length of the length of the bending actuation wire before and after bending can be represented as the following equation: <MAT> <MAT> <MAT> <MAT> <MAT>.

Herein, R = L/(2tan(θ/<NUM>)) + d; <MAT>.

<FIG> is a simulation result illustrating the total length change (ΔL) of the bending actuation wires as a function of the bending angle θ calculated using Matlab. For example, when, L = <NUM>, d = <NUM>, ΔL remains <<NUM> when θ is within the range of motion of the designed joint (<NUM> to <NUM> degrees); so the slack caused by wire elongation can be compensated by ΔL, made possible by off-axis hinge joints.

Thus, pivot motion of the intermediate joint <NUM> occurs on the hinge <NUM> located offset from the longitudinal axis direction of the intermediate joint <NUM>. The length of bending actuation wires is altered and kept in a predetermined length in that the elongation of the bending actuation wires is compensated by the off-axis pivot motion.

<FIG> is a block diagram illustrating a surgical instrument according to an exemplary embodiment. <FIG> is a schematic view illustrating a surgical instrument according to an exemplary embodiment. As illustrated in <FIG> and <FIG>, a steerable member <NUM> that is bendable is provided at the distal end of the surgical instrument <NUM>. The steerable member <NUM> has a plurality of bending segments <NUM> with hollow channels (not shown in <FIG> and <FIG>) that are connected together. Each bending segment <NUM> comprises a plurality of lumens <NUM> that are formed lengthwise. A flexible member <NUM> comprising a flexible material is provided at the proximal end of the steerable member <NUM>. The flexible member <NUM> may comprise a hollow tube where various types of wire members connected from the distal end of the surgical apparatus <NUM> are located. Optionally, an end effector <NUM> is provided at the distal end of the steerable member <NUM>, and the end effector <NUM> may be selectively actuated by an effector actuation wire <NUM> (e.g. see <FIG>, <FIG>).

Each bending segment <NUM> of the steerable member <NUM> is connected to adjacent bending segments in a way that allows hinge movement, and bent by a bending actuation wire <NUM> (see, e.g. <FIG>). In this exemplary embodiment, a first bending actuation wire 403a and a second bending actuation wire 403b that are located in separate lumens <NUM> to pass through the steerable member <NUM> and the flexible member <NUM>, and the distal ends of the first bending actuation wire 403a and second bending actuation wire 403b are connected to the steerable member <NUM> and their proximal ends are mechanically connected to a drive member <NUM>. Accordingly, when the first bending actuation wire 403a and second bending actuation wire 403b are moved by the drive member <NUM>, the plurality of bending segments <NUM> move hingedly, thus causing <NUM>-DOF bending motion of the steerable member <NUM>.

The drive member <NUM> comprises a first motor <NUM>, a second motor <NUM>, a first motion transmitting unit <NUM> and a second motion transmitting unit <NUM>. The first motor <NUM> is coupled to the first bending actuation wire 403a via a first motion transmitting unit <NUM>, so that the power from the first motor <NUM> may be transmitted to the first bending actuation wire 403a to make it actuate. Similarly, the second motor <NUM> is coupled to the second bending actuation wire 403b via a second motion transmitting unit <NUM>, transmitting the power from the second motor <NUM> to actuate the second bending actuation wire 403b. In this exemplary embodiment, the first motion transmitting unit <NUM> and the second motion transmitting unit <NUM> may be a lead screw or ball screw, but not limited to this.

A tension monitoring member <NUM> is further provided, comprising: a first sensor <NUM> and a second sensor <NUM>. The first sensor <NUM> is coupled to the first motion transmitting unit <NUM> and coupled to the first bending actuation wire 403a. The first sensor <NUM> may provide a first feedback signal S1 responsive to sensing change in tension force of the first bending actuation wire 403a between the pre-bending and the desired bending motion. Similarly, a second sensor <NUM> is coupled to the second motion transmitting unit <NUM> and the second bending actuation wire 403b. The second sensor <NUM> may provide a second feedback signal S2 responsive to sensing change in tension force of the second bending actuation wire 403b between the pre-bending and the desired bending motion. In this embodiment, the first sensor <NUM> and the second sensor <NUM> are load cells, but not limited to this. The change in tension force of the first bending actuation wire 403a or the second bending actuation wire 403b provides an electrical value change (e.g. voltage, current or other parameters) that is calibrated to the load placed on the load cell.

The drive member <NUM> and the tension monitoring member <NUM> as described above are further electrically connected to a control member <NUM>. The control member <NUM> may provide a first output signal S3 responsive to the first feedback signals <NUM> and transmit to the first motor. Upon receiving the first output signal S3, the first motor <NUM> will be driven to adjust (i.e. pull or release) the first bending actuation wire 403a. Similarly, the control member <NUM> may provide a second output signal S4 responsive to the second feedback signal S2, and transmit to the second motor <NUM> to adjust the second bending actuation wire 403b.

<FIG> is a view illustrating a surgical instrument in a bending status according to an exemplary embodiment. When the first bending actuation wire 403a is actuated (i.e. pulled toward the direction of the first motor <NUM> as shown in <FIG>) in order to bend the steerable member <NUM>, tension of the first bending actuation wire 403a and /or the second bending actuation wire 403b changes because of various reasons. For example, change in the length between before and after bending along the bending direction of the second bending actuation wire 403b is smaller that of the first bending actuation wire 403a. Accordingly, tension of the second bending actuation wire 403b will be changed and backlash will be created due to bending, thus making fine adjustment difficult.

In this exemplary embodiment, the change in tension force caused by the first bending actuation wire 403a can be measured and monitored respectively by the first sensor <NUM> and the second sensor <NUM> via the voltage change induced by tension force. Then, the first feedback signal S1 and the second feedback signal S2 are provided to the control member <NUM> in response to the voltage change. After receiving and processing the first feedback signal S1 and the second feedback signal S2, the control member <NUM> will provide the first output signal S3 and the second output signal S4 to the first motor <NUM> and the second motor <NUM>, separately. Then, the first motor <NUM> will be motionless in response to the first output signal S3, while the second motor <NUM> will release the second bending actuation wire 403b toward the direction of the steerable member <NUM> until the predetermined length in response to the second output signal S4, so that the first bending actuation wire 403a and the second bending actuation wire 403b will be maintained under a predetermined tension again.

<FIG> is a block diagram illustrating a surgical instrument according to another exemplary embodiment. <FIG> is a schematic view illustrating a surgical instrument according to another exemplary embodiment. The end effector <NUM> may be subjected to various external forces as it is brought into frequent contact with a body wall or creates friction against a body material while being pushed forward along a pathway in the body or creates reaction force when operates the end effector <NUM>. In the traditional surgery, a surgeon feels such external force by their own finger(s). However, in the robotic surgery, surgeons cannot feel the external force directly and all they can do is guess only by their observation or experience.

Thus, in this embodiment, the surgical instrument <NUM> provided herein may function together with a surgeon station <NUM> via a communication member <NUM>.

The first sensor <NUM> and the second sensor <NUM> as described above may be configured to determine whether an external force is applied or not, depending on whether the potential difference between the sensed value and the value that tension in normal operation applied to the steerable member <NUM> exceeds a preset threshold value ΔVth. When the external force is determined to be applied, the first sensor <NUM> and the second sensor <NUM> will provide a first external-force signal S5 and a second external-force signal S6 respectively to the control member <NUM>. The control member <NUM> will further provide an instruction signal S7 transmitted via communication member <NUM> in response to the first external-force signal S5 and the second external-force signal S6.

The communication member <NUM> may be a build-in one within the control member <NUM> or an external one. Also, the communication member <NUM> may use any telecommunication technology in the art. For example, in some embodiments, the communication member <NUM> may comprise a wireless transmitter and a wireless receiver (not shown in FIGs). In other embodiments, where the signal is digital, or digitized, and modulated by the control member <NUM>, wireless transmitter may be configured according to a standard protocol, e.g., Bluetooth®. Alternatively, any other suitable configuration of hardwired or wireless transmitter, standard or proprietary, may be used. Further, wireless transmitter may include an antenna (not shown) extending therefrom to facilitate transmission of the signal to wireless receiver.

The surgeon station <NUM> is adapted to be manually manipulated by surgeons to, in turn, control motion of the surgical instrument <NUM> in response to the surgeons' manipulation. In this embodiment, the surgeon station <NUM> is configured to display information related to resistance force or vibration in response to the instruction signal S7 to surgeon station <NUM>. In one embodiment, the control member <NUM> as described above may comprise a haptic feedback controller (not shown in the FIGS) to process and transmit the instruction signal S7 in form of haptic feedback. The haptic feedback may be provided through various forms, for example, mechanosensation, including, but not limited to, vibrosensation (e.g. vibrations), force-sensation (e.g. resistance) and pressure-sensation, thermoperception (heat), and/or cryoperception (cold). The surgeon station <NUM> may comprise a haptic joystick (not shown in the FIGS) to transfer haptic feedback to the surgeons to inform them of the external force.

In other embodiments, the information related to resistance force or vibration may be shown as graphical information or acoustic information. The surgeon station <NUM> herein may be various types known in the art that comprises a user's interface to display such graphical information or acoustic information. With the surgical instrument <NUM> provided herein, the external force may be detected and monitored by the tension monitoring member <NUM> and be displayed in a visualized form or be sensed by haptic feedback. Thus, surgeons can apply additional force using master device in the surgeon station timely against the external force, even in a tele-operation condition. Also, the accuracy to perform surgeries using the surgical instrument <NUM> will be increased.

In a further aspect, the disclosure further describes a personalized master controller for use with robots and the like, and particularly to robotic surgical devices, systems, and methods. In robotically assisted surgery, the surgeon typically operates a master controller to remotely control the motion of robotic surgical devices at the surgical site. The master controller may be separated from the patient by a significant distance (e.g., across the operating room, in a different room, or in a completely different building than the patient). Alternatively, a master controller may be positioned quite near the patient in the operating room. Regardless, the master controller will typically include one or more manual input handles so as to move a surgical apparatus <NUM> as shown in <FIG> based on the surgeon's manipulation of the manual input handle. Typically, the manual input handle may be designed so as to allow smooth motion in the six degrees of freedom which may correspond to translations in three axes, as well as rotation in three axes.

Further, in order to drive the surgical instrument <NUM> to perform various surgical operations, the manual input handle itself may provide a degree of freedom for gripping motion. For example, a built-in gripping device may be further provided at the proximal end of the manual input handle, so that the gripping device may be levered to allow an operator to emulate the motion of scissors, forceps, or a hemostat and control actuation of surgical instrument <NUM>, such as, to actuate the end-effector <NUM> (see <FIG> )to move tissue and/or other material at the surgical site by gripping the same. However, such a gripping device may not be replaceable, and thus operators have no choice but are forced to use the manual input handle with the gripping device that they may not very familiar with. Precise control using a master controller for surgical operations may thus become more difficult.

For the reasons outlined above, it would be advantageous to provide improved devices, systems, and methods for robotic surgery, telesurgery, and other telerobotic applications. In an exemplary embodiment, a personalized master controller is provided herein. <FIG> is a block diagram illustrating a personalized master controller according to an exemplary embodiment. The personalized master controller <NUM> may be coupled to a processor P (e.g. a computer) that is electrically connected to the surgical apparatus <NUM>. As provided herein, the personalized master controller <NUM> may comprise a control platform <NUM>, a connecting part <NUM>, and an interchangeable grip <NUM>. As shown in <FIG>, the control platform <NUM> may be configured to define and input one or more movement signals to control movement of the surgical apparatus <NUM> (see, e.g. <FIG> ) via the processor P.

In some alternative embodiments, the control platform <NUM> may be a serial manipulator, comprising: a number of rigid links connected with joints as described in <CIT>, <CIT>, and <CIT>. For example, as shown in <FIG>, this type of the control platform <NUM> may comprise: a body <NUM> comprising a base 900a, an input handle <NUM> and a first plurality of sensors <NUM>. The base 900a may rotate with respect to a first axis A01 having a substantially vertical orientation. The input handle <NUM> may comprise a first link <NUM>, a second link <NUM> and a gimbal structure comprising an outer gimbal <NUM> and an inner gimbal <NUM>. The first link <NUM> is pivoted to the body <NUM> via a first joint <NUM> which allows the first link <NUM> to move with respect to a second axis A02 having a substantially perpendicular orientation relative to the first axis A01. The second link <NUM> is pivoted to the first link <NUM> via a second joint <NUM> which allows the second link <NUM> to move with respect to a third axis A03 which is substantially parallel to the second axis A02.

A gimbal structure is mounted to the free end of the second link <NUM> comprising an outer gimbal <NUM> and an inner gimbal <NUM>. The outer gimbal <NUM> is pivotally supported by the second link <NUM> and allowed to rotate with respect to a fourth axis A04 which is substantially perpendicular to the third axis A03. The inner gimbal <NUM> is pivotally supported by the outer gimbal <NUM> and allowed to rotate with respect to a fifth axis A05 which is substantially perpendicular to the fourth axis A04. A connecting part <NUM> (<FIG>) is mounted on the inner gimbal structure <NUM> and allows the interchangeable grip <NUM> that is electrically connected thereto to rotate with respect to a sixth axis A06.

The connecting part <NUM> mounted on the inner gimbal structure <NUM> electrically connects the input handle <NUM> and the interchangeable grip <NUM>. <FIG> is a perspective view illustrating a connecting part connected to the control platform according to an exemplary embodiment. In one embodiment, the connecting part <NUM> may be a plug-and-socket type connector, but not limited to this. As shown in <FIG>, in one embodiment, a one-prong plug <NUM> of the connecting part <NUM> may be coupled to the inner gimbal <NUM> while a corresponding socket structure <NUM> may be mounted at the distal end of the interchangeable grip <NUM> (see <FIG>), such that the interchangeable grip <NUM> can be connected to on the inner gimbal structure <NUM> and be allowed to rotate with respect a sixth axis A06 which is substantially perpendicular to the fifth axis A05. Alternatively, in some embodiments, the one-prong plug <NUM> of the connecting part <NUM> may be coupled to the distal end <NUM> of the interchangeable grip <NUM> while the socket structure <NUM> may be mounted the inner gimbal <NUM> (see <FIG>).

Thus, the control platform <NUM> can provide six degrees of freedom movement including three translational degrees of freedom (in X, Y, and Z directions) and three rotational degrees of freedom (in pitch, yaw, and roll motion). The input handle <NUM> thereby can provide a plurality of position parameters P1 when it is translatable itself or with the mounted interchangeable grip <NUM> in X, Y, and Z direction with respect to the control platform <NUM> and/or provide a plurality of orientation parameters P2 when it is rotatable itself or with the mounted interchangeable grip <NUM> in pitch, yaw, and roll motion with respect to the control platform <NUM>.

In one embodiment, one or more first sensors <NUM> may be mounted to the input handle <NUM> and configured to and generate one or more first movement signals S8 in response to the above-mentioned position parameters P1 and/or the orientation parameters P2. The first sensors <NUM>, may, for example, be mounted to the first joint <NUM>, the second joint <NUM> and/or the gimbal structure <NUM>. In some embodiments, the first sensors <NUM> may be any type of sensors capable of measuring the position parameters P1 and/or the orientation parameters P2 based on the status or changes such as position, orientation, force, torque, speed, acceleration, strain, deformation, magnetic field, angle and/or light (but not limited to this) caused by the motion of the input handle <NUM> and/or mounted interchangeable grip <NUM>. For example, the first sensors <NUM> may be pressure or force sensor, including but not limited to a piezoelectric sensor, a simple piezoelectric crystal, a Hall-Effect or a resistive strain gauge sensor, etc., all of which can be either stand-alone or integrated with signal-conditioning electronics (Wheatstone bridge, low-noise amplifier, A/D converter, etc.) into a single chip or single package sealed module. In other embodiments, may be an angle sensor, or a rotational sensor, but not limited to this. In a specific embodiment, the first sensor <NUM> may be a Hall-Effect sensor. As known in the art, the Hall-Effect sensor may be used in the presence of a corresponding magnet element (not shown in the FIGs. ) to sense the magnetic field responding to the position parameter P1 and/or the orientation parameter P2. Then, the first sensors <NUM> may produce a first movement signal S8 to control movement of the surgical apparatus <NUM>(e.g., roll, translation, or pitch/yaw movement) accordingly.

<FIG> is a perspective view illustrating an interchangeable grip according to an exemplary embodiment. In one embodiment, the interchangeable grip <NUM> provided herein may comprise a detachable handle <NUM> to mimic actual handles from manual surgical instruments. i.e., it may be the same size and shape, and can be squeezable or fixed, in order to provide realism to the surgeon. For example, two grip levers <NUM>, <NUM> shown in FIG. <NUM> A may be pivoted at the proximal end of the detachable handle <NUM> so as to provide a degree of freedom of pinching or grasping motion. Both grip levers <NUM>, <NUM> may be allowed to move toward each other relative to the detachable handle as indicated by arrows H to provide a degree of freedom of pinching or grasping motion. To mimic actual standard surgical handles depending on a field, surgeon, or operation, the detachable handle <NUM> and grip levers <NUM>, <NUM> may be designed to be interchangeable as various types of surgical tools such as tweezers or laparoscopic hand Instruments as shown <FIG> and <FIG>, respectively.

Also, in some embodiments, the detachable handle <NUM> may be mounted to or detach from the socket structure <NUM> at its distal end <NUM>. The socket structure <NUM> provided herein may be capable of electrically connecting to or disconnecting from the one-prong plug <NUM> of the connecting part <NUM>, so that the detachable handle <NUM> may be instrumented accordingly to receive relevant gripping motion input from the surgeon and the corresponding control signals are subsequently produced and transmitted to the surgical apparatus <NUM> via the control platform <NUM>.

To sense gripping motion of the interchangeable grip <NUM>, in one embodiment, the detachable handle <NUM> may define an inner hollow tubular space where a second sensor <NUM> may be housed to sense at least one parameter P3 based on the status or changes such as position, orientation, force, torque, speed, acceleration, strain, deformation, magnetic field, angle and/or light (but not limited to this) caused by the motion of the grip levers <NUM>, <NUM>.

In some embodiments, the second sensor <NUM> may be any type of sensors known in the art. For example, the second sensors <NUM> may be pressure or force sensor, including but not limited to a piezoelectric sensor, a simple piezoelectric crystal, a Hall-Effect or a resistive strain gauge sensor, etc., all of which can be either stand-alone or integrated with signal-conditioning electronics (Wheatstone bridge, low-noise amplifier, A/D converter, etc.) into a single chip or single package sealed module. In other embodiments, the second sensors <NUM> may be an angle sensor, or a rotational sensor, but not limited to this. In a specific embodiment, the second sensor <NUM> may be a Hall-Effect sensor. The Hall-Effect sensor may be used in the presence of a corresponding magnet element (not shown in the FIGs. ) to sense the magnetic field as known in the art, such that the Hall-Effect sensor may measure the gripping parameters P3 and /or P4 based on the status or changes of the magnetic field caused by the motion of the grip levers <NUM>, <NUM>. Then, the Hall-Effect sensor may produce a second movement signal S9 that can control the movement of the end-effector <NUM> shown in <FIG> accordingly. (e.g. opening and closing (gripping) movement of the end-effector <NUM> that may be a gripping device (e.g., jaws or blades).

<FIG> is a view schematically illustrating a personalized master controller according to another exemplary embodiment. <FIG> is view schematically illustrating parts of the control platform of the personalized master controller in <FIG>. In this embodiment, the control platform <NUM> may be a device comprising parallel kinematics structures, in particular, a Delta parallel kinematics structure device (for example, as described in <CIT>. As shown in <FIG>, the control platform <NUM> is adapted to provide up to six degrees of freedom (i.e. up to three translational degrees of freedom in X, Y, and Z directions and up to three rotational degrees of freedom in pitch, yaw, and roll orientations to provide a position parameter and an orientation parameter, respectively.

In this embodiment, the control platform <NUM> may comprise: a base member <NUM>, a moveable member <NUM>, and three parallel kinematics chains <NUM> coupling the base member <NUM> and the moveable member <NUM>, respectively. Each parallel kinematics chain <NUM> having a first arm <NUM> moveable in a respective movement plane <NUM> which is at a distance to a symmetry axis (i.e. the central line perpendicular to the base member <NUM>). Each first arm <NUM> is coupled with its associated mounting member <NUM> such that each first arm <NUM> may be rotated or pivoted with respect to the associated mounting member <NUM> and, thus, with respect to the base member <NUM>.

The parallel kinematics chains <NUM> comprising a second arm <NUM> may be coupled to the moveable member <NUM>. Each second arm <NUM> may be considered as parallelogram including two linking bars 952a, 952b. At proximal end of the second arm <NUM>, each linking bar 952a and 952b may be coupled with the moveable member <NUM> by a joint or hinge <NUM>. At the distal end of the second arm <NUM>, each linking bar 952a, 952b are coupled with an end of its associated first arm <NUM> by a joint or hinge <NUM>. Each second arm <NUM>, particularly each linking bar 952a, 952b, may have two rotational degrees of freedom at both ends.

Thus, each kinematics chain <NUM> connected between the base member <NUM> and the moveable member <NUM> may be moved in a movement space defined by the base member <NUM>, the moveable member <NUM>, and three parallel kinematics chains <NUM> to provide up to three translational degrees of freedom (along the X, Y, and Z directions, respectively as shown in <FIG>), generating one or more position parameters P1. More details for the Delta parallel kinematics structure device may be referred to, for example, <CIT>.

In addition, up to three rotational degrees of freedom may be provided by a wrist structure <NUM> coupled to the moveable member <NUM>, comprising a three pivotable connections <NUM>, <NUM> and <NUM>, for example in form of pivot joints. Each of the pivotable connections <NUM>, <NUM> and <NUM> provides a rotational degree of freedom with respect to the moveable member <NUM> (in yaw, pitch, and roll orientations respectively in <FIG>), and generates one or more orientation parameters P2 thereby.

There are a plurality of first sensors <NUM> provided to detect one or more position parameters P1 and/or the orientation parameters P2 caused by the movement of three parallel kinematics chains <NUM> and the moveable member <NUM>, followed by generating first movement signals S8 in response to the parameter(s) P1 and or P2. For example, some first sensors <NUM> may be installed to each mounting member <NUM> respectively to detect at least one parameter caused by the motion of the associated first arm <NUM>. Other first sensors <NUM> may be installed to all or parts of joint or hinge <NUM> respectively to detect at least one parameter caused by the motion of the associated second arm <NUM>. Alternatively, three first sensors <NUM> may be provided at three pivotable connections <NUM>, <NUM> and <NUM> respectively.

<FIG> is an enlarged view of a portion of <FIG> showing the interchangeable grip being attached to the moveable member of the control platform according to an exemplary embodiment. <FIG> is also an enlarged view of a portion of <FIG> showing the interchangeable grip being detached from the moveable member of the control platform according to an exemplary embodiment. As shown in <FIG>, a connecting part <NUM> is further mounted on the pivotable connection <NUM>, such that it can electrically connect the input handle <NUM> and the interchangeable grip <NUM>. As shown in <FIG>, in one embodiment, the connecting part <NUM> may comprise be a plug-and-socket type connector, but not limited to this. For example, a one-prong plug <NUM> of the connecting part <NUM> may be coupled to the detachable handle <NUM> of the interchangeable grip <NUM> via a thread <NUM>, while a corresponding socket structure <NUM> may be mounted at the pivotable connection <NUM>, so that that the interchangeable grip may be attached to (see <FIG>) or detached from (see <FIG>) the pivotable connection <NUM> and allowed to rotate with respect to the rotational axis A10 of the pivotable connection <NUM>.

As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, product, article, or apparatus that comprises a list of elements is not necessarily limited only those elements but may include other elements not expressly listed or inherent to such process, product, article, or apparatus.

Claim 1:
A surgical apparatus comprising:
a steerable member (<NUM>) that is bendable and comprises a plurality of bending segments (<NUM>), each bending segment comprising at least a lumen (<NUM>) and at least an intermediate joint (<NUM>) that is arranged along a longitudinal axis direction of each bending segment and has a first link portion (<NUM>) and an opposing second link portion (<NUM>) wherein two off-axis hinge joints (<NUM>) are formed therebetween, wherein each hinge joint comprises:
a pair of first interfacing halves (<NUM>, <NUM>') extending from the first link portion toward the second link portion, each first interfacing half comprising a first first engagement surface (<NUM>) and a second first engagement surface (<NUM>') disposed side by side, each of the first and second first engagement surfaces extending along a portion of a round path; and
a corresponding pair of second interfacing halves (<NUM>, <NUM>'), each second interface half comprising a first second engagement surface (<NUM>) and a second second engagement surface (<NUM>') disposed side by side and having a complementary surface to the corresponding first engagement surface, wherein the first link and second link are pivotable with respect to one another from a position wherein the first first engagement surface is in contact with the first second engagement surface simultaneously with the second first engagement surface being in contact with the second second engagement surface to a position wherein the first first engagement surface remains in contact with the first second engagement surface while the second first engagement surface is spaced from the second second engagement surface and to a position wherein the second first engagement surface remains in contact with the second second engagement surface while the first first engagement surface is spaced from the first second engagement surface, wherein the pair of first interfacing halves and the pair of second interfacing halves thereby form two different hinge axes offset from the longitudinal axis; a plurality of bending actuation wires (<NUM>) disposed through the lumen to bend the steerable member.