CN110575257B

CN110575257B - Surgical robot surgical equipment

Info

Publication number: CN110575257B
Application number: CN201910999014.1A
Authority: CN
Inventors: 王林玲
Original assignee: Chongqing Normal University
Current assignee: Chongqing Normal University
Priority date: 2019-10-21
Filing date: 2019-10-21
Publication date: 2022-04-22
Anticipated expiration: 2039-10-21
Also published as: CN110575257A

Abstract

The invention discloses surgical equipment of a surgical robot, which belongs to the field of surgical robots and comprises the following components: the forceps head is contacted with the human tissue and is used for directly operating the human tissue; the equipment pipe is connected with the tong head; the fixing part, it and equipment union coupling are equipped with two at least motors in the fixing part, the fixing part passes through equipment pipe drive binding clip and opens and close and rotate, the fixing part install and carry out on the robot and install surgical instruments on the robot, the robot be used for providing a plurality of degrees of freedom to surgical instruments.

Description

Surgical robot surgical equipment

Technical Field

The present invention relates to the field of surgical robots.

Background

Along with the expansion of the operation range, surgical instruments are continuously increased, improved and updated, but the common surgical instruments are not limited to knives, scissors, needles, tweezers, pincers, hooks and the like, and the instruments are required to be continuously replaced and used in the operation.

With the technology being reversed, the surgical robot is being slowly applied to the human body operation, and the replacement of the surgical instrument actually needs to be integrally replaced, which is time-consuming and labor-consuming, and causes the surgical robot operation cost to be high.

Disclosure of Invention

The invention aims to: to address the above existing problems, a surgical robotic surgical device is disclosed, comprising:

the forceps head is contacted with the human tissue and is used for directly operating the human tissue;

the equipment pipe is connected with the tong head;

the fixing part is connected with the equipment tube, at least two motors are arranged in the fixing part, the fixing part drives the tong head to open and close and rotate through the equipment tube, the fixing part is arranged on the robot body to install surgical equipment on the robot body, and the robot body is used for providing multiple degrees of freedom for the surgical equipment;

the equipment pipe comprises a driving part and a driven part, the driving part is connected with the fixing part, the driven part is connected with the tong head, the driving part is detachably connected with the driven part, the driving part comprises a driving pipe and a driving rod, the driven part comprises a driven pipe and a driven rod, the driving pipe is detachably connected with the driven pipe, the driving rod is detachably connected with the driven rod, the driving pipe and the driven pipe form an outer pipe to support the tong head, and the driving rod and the driven rod form a power rod to drive the tong head to open and close and drive the tong head to rotate relative to the outer pipe;

the driven rod comprises a movable cavity, a clamping part is arranged in the movable cavity, the clamping part is provided with a hinged shaft to hinge the clamping part on the movable cavity, the other end of the clamping part is a clamping head, the driving rod is provided with a clamping groove, the clamping head can rotate around the hinged shaft to enable the clamping head to be clamped into the clamping groove and further fix the driving rod and the driven rod, the clamping head can be removed from the clamping groove to disassemble the driving rod and the driven rod, the clamping part is provided with a movable groove, the driven rod further comprises a sliding rod, a movable column is arranged on the sliding rod, the movable rod is clamped into the movable groove, and the sliding rod moves to enable the movable column to move in the movable groove to further drive the clamping head to rotate around the hinged shaft;

the driven rod further comprises a screw rod, a central channel is formed inside the slide rod, the slide rod is connected with a screw rod lead screw through the central channel, and the screw rod is fixed on the driven rod and the driven tube and can axially rotate to drive the slide rod to move.

As an improvement, the driven rod and the driven pipe are both provided with fixing holes (3211), and a screw rod can penetrate through the fixing holes.

As an improvement, the driven rod is provided with a fixed channel for accommodating the sliding rod, and the fixed channel limits the axial rotation of the sliding rod so that the sliding rod can only move axially.

As an improvement, the tail end of the clamping head is gradually thinned so that the clamping head can be clamped into the clamping groove and fixed by the clamping groove.

As an improvement, the driving rod is provided with a convex part, the clamping groove is positioned on the side surface of the convex part, the driven rod is provided with a concave part, the concave part is communicated with the movable cavity, and the convex part can be inserted into the concave part and matched with the concave part.

As a modification, the cross sections of the concave part and the convex part are semicircular.

Drawings

Fig. 1 is an overall schematic view of an operation unit;

fig. 2 is a schematic view of the boom unit;

FIG. 3 is a schematic view of a stationary unit;

FIG. 4 is a schematic view of an operating device;

FIG. 5 is a side elevational view of the operating device;

FIG. 6 is a cross-sectional view of the operation device;

FIG. 7 is a schematic view of a connector holder;

FIG. 8 is a schematic view of the housing;

FIG. 9 is a schematic view of a motor cavity;

FIG. 10 is a schematic view of the housing;

FIG. 11 is a schematic view of a surgical instrument;

FIG. 12 is a schematic view of a third electric machine;

FIG. 13 is a schematic view of the surgical equipment of example 2;

FIG. 14 is a schematic view of a driving portion and a driven portion;

FIG. 15 is a schematic view of a follower link;

FIG. 16 is a schematic view of a follower link;

FIG. 17 is a schematic view of a follower link;

FIG. 18 is a schematic view of a follower link;

FIG. 19 is a schematic view of an active lever;

FIG. 20 is a schematic view of an active lever;

FIG. 21 is a schematic view of a slide bar;

the labels in the figure are:

example 1: 1-operating table, 2-rotating arm unit, 21-first rotating arm, 22-second rotating arm, 23-third rotating arm, 24-fourth rotating arm, 25-slide, 26-first screw, 27-driving motor, 28-connecting piece, 3-operating device, 31-fixed rod, 32-housing, 321-arc channel, 33-surgical instrument, 331-second movable groove, 332-fixed seat, 333-second screw, 334-third motor, 3341-stator, 3342-rotor, 3343-long rod, 3347-rotating ring, 3345-one-way converter, 3346-output rod, 335-sliding unit, 336-long arm, 337-fixed part, 34-first motor, 35-sliding rod, 351-first movable groove, 36-movable unit, 361-first movable rod, 362-second movable rod, 363-first movable column, 364-second movable column, 365-first connecting seat, 366-second connecting seat, 3661-connecting column, 37-second motor, 38-fixed frame, 381-second fixed tube, 382-first fixed tube, 383-power rod.

Example 2-robot body 1-fixed part, 3-equipment tube, 31-driving part, 311-driving tube, 312-driving rod, 3121-convex part, 3122-neck, 32-driven part, 321-driven tube, 3211-fixed hole, 322-driven rod, 3221-concave part, 3222-clamping part, 3223-articulated shaft, 3224-chuck, 3225-movable groove, 3226-sliding rod, 3227-screw rod, 3228-movable post, 4-forcep head.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings.

Example 1:

as shown in fig. 1, the clinical operation bed assembly comprises an operation bed 1, a fixing unit fixed at the edge of the operation bed 1, a rotating arm unit 2 connected with the fixing unit and an operating device 3 fixed at the tail end of the rotating arm unit, wherein the operating device 3 is provided with a surgical instrument and used for performing operation, and the rotating arm unit is provided with a plurality of rotating arms which can provide a plurality of rotating degrees of freedom for the operating device 3 so as to facilitate the operation of the operating device 3.

In a specific embodiment, in order to make the surgical instrument move according to different positions of the human body on the bed, especially the position of the width direction of the operation bed, in a preferred embodiment, as shown in fig. 3, the fixing unit comprises a connecting part 28, a first screw 26 fixed on the connecting part, a driving motor 27 driving the first screw to rotate, a slider 25 in threaded connection with the screw, the slider 25 and a first rotating arm are fixedly connected, the driving motor 27 drives the first screw to rotate, further drives the slider to move along the axial direction of the screw, the axial direction of the screw is perpendicular to the X direction, the X direction is the direction shown in fig. 2, the driving motor 27 can be controlled remotely or controlled in the operation room, the driving motor rotates, the slider 25 moves along the axial direction of the first screw, namely the edge of the operation bed, so as to adjust the position of the surgical instrument according to the position of the human body, can be based on the accuracy relative to manual operation and does not need to move the position of the patient.

In a specific embodiment, in order to provide the surgical instrument with a plurality of rotational degrees of freedom, as shown in fig. 2, the arm unit 2 includes a first arm 21 connected to the fixed unit, a second arm 22 connected to the first arm, a third arm 23 connected to the second arm, and a fourth arm 24 connected to the third arm, the first arm and the second arm being capable of rotating axially in the X direction, the second arm and the third arm being capable of rotating axially in the Y direction, the third arm and the fourth arm being capable of rotating axially in the Z direction, the X direction being perpendicular to the Y direction, the Y direction being perpendicular to the Z direction, the fourth arm 24 being fixed with the operating device 3, the joints of the adjacent arms being capable of rotating under the control of a motor or manually operating the rotation thereof, the mutual rotation of the four arms providing the surgical instrument with a plurality of rotational degrees of freedom, and thereby performing the surgical operation more flexibly.

In a specific implementation, as shown in fig. 5, the operating device 3 includes a first motor 34, a sliding rod 35, a first movable rod 361 and a second movable rod 362, the first motor is connected to the sliding rod 35 through a motor shaft, the first motor 34 rotates to drive the sliding rod 35 to rotate along the direction of the motor shaft, two ends of the sliding rod are respectively provided with a first movable slot 351, the axial directions of the first movable rod 361 and the second movable rod 362 are parallel to each other, the proximal end of the first movable rod 361 is provided with a first movable post 363, the proximal end of the second movable rod is provided with a second movable post 364, the first movable post and the second movable post are respectively clamped into the two first movable slots 351 of the sliding rod, and when the first motor 34 drives the sliding rod to rotate, the first movable rod and the second movable rod can move in opposite directions along the axial direction of the two arrows in fig. 2.

As shown in fig. 6, the operation device 3 further includes a surgical instrument 33, the first movable rod and the second movable rod are respectively connected to the surgical instrument at different points, such as point a and point B in fig. 6, a first connecting seat 365 is disposed at a distal end of the first movable rod and hinged to the surgical instrument at point a, a second connecting seat 366 is disposed at a distal end of the second movable rod, and a connecting column 3661 (shown in fig. 7) 6 is disposed on the second connecting seat, as point B in the figure, a second movable slot 331 is disposed on the surgical instrument, the connecting column is clamped in the second movable slot, and the connecting column can move in the second movable slot, so as to drive the surgical instrument to rotate along the first axis when the first movable rod and the second movable rod move in opposite directions under the condition that the distance between the two movable rods is unchanged.

The operating device 3 further includes a second motor 37, a fixed frame 38, and a housing 32 (shown in fig. 4), the first motor and the second motor are fixed on the housing 32, the fixed frame 38 includes a first fixed tube 382 and a second fixed tube 381 for the first movable rod and the second movable rod to pass through, respectively, the second motor is connected to the fixed frame through a power rod 388, and the second motor drives the fixed frame to rotate around the axial direction of the power rod through the power rod, further drives the first movable rod, the second movable rod, and the surgical instrument to rotate along the axial direction of the power rod, the axial direction of the power rod is a second axial direction, and the first axial direction and the second axial direction are perpendicular and intersect. The distance between the two movable rods is limited by the two fixed tubes on the fixed frame, so that the two movable rods always keep the same distance, and the fixed frame can drive the two movable rods to rotate by being driven to rotate so as to further drive the surgical instrument to rotate. When the distance between the movable rods is fixed, in order to ensure that the movable rods can move reversely, the second movable groove 331 is arranged on the surgical instrument, so that when the distance between the point A and the point B can further enable the surgical instrument to rotate automatically along with the movement and the change of the movable rods, further, the positions of the movable rods in the horizontal direction are fixed by the fixed frame, and therefore, the first movable groove is arranged, the first motor can drive the two movable rods to move up and down under the condition of equal distance, therefore, the surgical instrument can rotate in two rotating directions, and the space required by rotation is greatly reduced.

Further, as shown in fig. 8, two arc-shaped channels are provided on the housing, the two arc-shaped channels are respectively used for the two movable rods to pass through, and when the two movable rods rotate around the second axial direction, the two movable rods can move in the arc-shaped channels.

In a specific embodiment, as shown in fig. 3 and 4, the operating device further includes a fixing lever 31 having one end connected to the boom unit and the other end fixedly connected to the housing 32.

In a specific embodiment, in order to fix the relative positions of the motor and the housing, as shown in fig. 8 and 9, the housing is respectively provided with a first motor cavity and a second motor cavity, the first motor is fixed in the first motor cavity, the second motor is fixed in the second motor cavity, the first motor and the second motor are further respectively fixed in the housing by fixing members such as screws, and the positions of the first motor and the second motor can be set according to specific requirements, as shown in fig. 9, the housing is an L-shaped structure, the first motor is located at the bottom of the housing, and the second motor is located at the vertical position of the housing.

The surgical instrument can be various existing surgical instruments, particularly surgical instruments with functions of grabbing, shearing, cutting, drilling, shooting and the like, and can also be surgical instruments in which artificial products can be implanted. In a specific embodiment, as shown in fig. 11, the surgical instrument includes a fixed base 332 connected to the first movable rod and the second movable rod, the fixed base is provided with a second screw rod 333, the second screw rod is connected to a third motor 334 and is driven by the third motor 334 to rotate, an axial direction of the second screw rod 333 is a third axial direction, the third axial direction is perpendicular to the first axial direction and the second axial direction, the second screw rod 333 is provided with a sliding unit 335 in threaded connection with the second screw rod 333, the sliding unit is connected to a long arm 336 capable of extending into a human body, a distal end of the long arm is provided with a surgical operation component (such as a grasping component, a cutting component, a drilling component, a clamping component, etc.) for performing a surgical operation, the second screw rod 333 is capable of driving the sliding unit to move along the third axial direction, and the fixed base is provided with a fixed portion 337 that limits the long arm to move only along the third axial direction relative to the fixed base.

The third motor 334 is a high power, low displacement motor, in some embodiments, an ultrasonic motor may be used, in a more preferred embodiment, as shown in a-d of fig. 12, the third motor 334 includes a cylindrical outer casing, the cross section of which is circular, four stators 3341 are fixedly connected to the outer casing, the four stators are uniformly distributed in the outer casing, the distance between two adjacent stators is the same, each stator is provided with an energizing coil to make the stator magnetic, the third motor further includes four rotors 3342, a rotor capable of moving between two adjacent stators is arranged between two adjacent stators, each rotor is connected with a long rod 3343, one end of each long rod is fixed on a fixed part, a hollow part is arranged in the middle of the circular ring of the fixed part, and a unidirectional converter 3345 is arranged in the hollow part, the unidirectional converter is preferably a unidirectional bearing, the outer ring of the unidirectional bearing and the connecting inner ring of the fixed part are fixedly connected with an output rod 3346, the side surface of the output rod is connected with the outer shell through a bearing, and the output rod is fixedly connected with the second screw rod or integrally formed; the rotor have magnetism, four rotors to the output pole equidistance, four stators to the output pole equidistance, can be put through the electric current that changes in direction on the stator so that the rotor can reciprocating motion between adjacent stator, and then the drive fixed part is round output pole reciprocating rotation, the transmission drive output pole through one-way bearing rotates and then drives the second screw rod and rotate.

Specifically, it can be seen from the diagrams a-d in fig. 12, taking a rotor and stators at two ends of the rotor as an example, as shown in the diagram a in fig. 12, the rotor is located in the middle of the stators, the rotor moves clockwise from the force of the magnetic force to approach the stators, the current is controlled to change the current when approaching, the direction of the magnetic force applied to the rotor changes to be counterclockwise at this time, the rotor is driven to rotate counterclockwise to approach the stators at the other end, as shown in the diagram c in fig. 12, the direction of the current changes, and the direction of the movement of the rotor changes. According to the repetition, due to the action of the one-way bearing, when the rotor drives the fixing part to rotate clockwise, the fixing part drives the output rod to rotate, and when the rotor rotates anticlockwise, the output rod idles clockwise, so that the output rod can only output along the clockwise direction.

In a specific embodiment, the stator is a partial ring, the rotor is a partial ring, the distance from the stator to the output rod is the same as the distance from the rotor to the output rod, the stator and the rotor are the same rings, and the outer housing is provided with a sensing element, so that when the distance between the rotor and the stator is reduced to a certain value, the sensing element can be sensed and the current direction on the stator can be changed through the controller.

In the motor, the rotor reciprocates, the stator can be arranged at the two ends of the rotor, the direction of the magnetic force applied to the rotor is the same as the moving direction of the rotor, and the stator can realize the maximum torque output to the rotor, thereby realizing high power; meanwhile, the fixing part of the invention can be simultaneously driven by four rotors (6, 8, 10 and … … 2N even numbers can be matched when the design principle of the invention is installed), thereby realizing high-power output and accurately controlling the operation of surgical instruments.

Example 2:

the embodiment discloses a surgical robot surgical device, as shown in fig. 13, the surgical device includes a forceps head 4, a device tube 3, and a fixing portion 3, the forceps head 4 is in contact with human tissue for directly operating the human tissue, the forceps head may be, but not limited to, a knife, scissors, a needle, forceps, a clamp, a hook, etc.; the equipment union coupling binding clip 4, under the usual condition, the part on the binding clip 4 articulates on the equipment pipe, and fixed part 2 and equipment union coupling are equipped with two at least motors in the fixed part, and two motors can be current conventional motor, have the third motor that can be high-power, little displacement in the middle of embodiment 1. Further, the fixing part 2 drives the forceps head 4 to open and close and rotate through the device 3, as shown in fig. 13, the fixing part 2 is mounted on the robot body 1 to mount the surgical device on the robot body, the robot body is used for providing multiple degrees of freedom for the surgical device, and the robot body in this embodiment may be the robot body in fig. 2, that is, the operation device and the operation unit mentioned in embodiment 1.

In order to make the surgical instrument detachable, the instrument tube 3 of the present embodiment can be separated, as shown in fig. 14, the instrument tube 3 includes a driving part 31 connected to the fixing part and a driven part 32 connected to the bit, the driving part and the driven part are detachably connected, the driving part includes a driving tube 311 and a driving rod 312, the driven part 32 includes a driven tube 321 and a driven rod 322, the driving tube and the driven tube are detachably connected, the driving rod and the driven rod constitute an outer tube to support the bit, the driving rod and the driven rod constitute a power rod to drive the bit to open and close and the bit to rotate relative to the outer tube, and the driving tube and the driven tube can adopt the existing connection methods, such as a snap connection method, a screw connection method, and the like.

In a further preferred embodiment, as shown in fig. 15, the driven rod 322 includes a movable cavity, a clamping portion 3222 is disposed in the movable cavity, the clamping portion is provided with an articulated shaft 3223 to articulate the clamping portion on the movable cavity, the other end of the clamping portion is a clamping head 3224, the driving rod 312 is provided with a clamping groove 3122, the clamping head can rotate around the articulated shaft to enable the clamping head to be clamped into the clamping groove to fix the driving rod and the driven rod, and to enable the clamping head to be removed from the clamping groove to detach the driving rod and the driven rod, the clamping portion is provided with a movable groove 3225, the driven rod further includes a sliding rod 3226, the sliding rod is provided with a movable post 3228, the movable rod is clamped into the movable groove, and the sliding rod moves to enable the movable post to move in the movable groove to further drive the clamping head to rotate around the articulated shaft; the driven rod further comprises a screw 3227, a central channel is formed inside the slide rod, the slide rod is connected with a screw rod lead screw through the central channel, and the screw rod is fixed on the driven rod and the driven tube and can axially rotate to drive the slide rod to move.

As shown in fig. 19, the driving rod is provided with a convex portion 3121, the slot is located at the side of the convex portion, as shown in fig. 15 and 16, the driven rod 322 is provided with a concave portion, the concave portion is communicated with the movable cavity, and the convex portion can be inserted into the concave portion and matched with the concave portion. As shown in fig. 16 and 19, the cross-sections of the concave portions and the convex portions are each semicircular.

As shown in fig. 14, 18 and 20, the driven rod and the driven tube are each provided with a fixing hole 3211 through which a screw rod can pass. The driven rod is provided with a fixed channel (not shown in the figure) for accommodating the sliding rod 3226, the fixed channel penetrates through the driven rod, the direction of the fixed channel is the same as that of the sliding rod, the section of the fixed channel is basically the same as that of the sliding rod so as to just accommodate the sliding rod, the fixed channel limits the axial rotation of the sliding rod so that the sliding rod can only axially move, and in the embodiment, the sectional view of the driven rod is shown in order to see the movable cavity in fig. 15-17.

In this embodiment, when the driving part and the driven part are connected, the position of the clamping part is as shown in fig. 15, for the purpose of sterilizing the equipment or replacing new equipment, when the surgical equipment needs to be replaced, it only needs to replace the forceps head and the driven part, the fixing part and the driving part do not need to be replaced, the screw rod is inserted into the fixing hole of the driven tube and the driven rod, the screw rod is rotated by a tool or a hand to move the slide rod, the slide rod moves to move the movable column in the movable groove, and at this time, the clamping part rotates counterclockwise around the hinge shaft 3223 (refer to fig. 15) until the position of fig. 16 is reached, the forceps head is removed from the clamping groove of the driving rod, the driving rod and the driven rod are detachable, and the driving tube and the driven tube are detached at the same time, and the driving part and the driven part are detachable.

The driven portion and bit of the present invention may be packaged with a screw, as shown in fig. 16, or with a tool and without a screw. When the driving part and the driven part need to be installed, the convex part of the driving rod is inserted into the concave part of the driven rod, the screw rod is rotated, the clamping part rotates to enable the clamping head to enter the clamping groove of the driving rod, and the driving rod and the driven rod are fixed. The depth of the concave part and the convex part ensures that the positions of the clamping groove and the clamping head are just corresponding when the tail end of the convex part is inserted into the bottom of the concave part.

The invention has convenient installation, the driving rod formed by the driving rod and the driven rod can rotate and move without influencing normal use, and the outer tube formed by the driving tube and the driven tube of the invention is completely flat with the fixed hole without additional structure. The replacement is quick and convenient. The driving part can be a plurality of different driven parts.

In a preferred embodiment, the tip of the chuck is tapered to enable the chuck to snap into the slot 3122 and be secured by the slot, the deeper the slot into which the chuck extends, the tighter the chuck is secured by the slot.

Claims

1. A surgical robotic surgical apparatus, comprising:

a forceps head (4) which is in contact with the human tissue and is used for directly operating the human tissue;

the equipment pipe (3) is connected with the tong head (4);

the fixing part (2) is connected with the equipment tube, at least two motors are arranged in the fixing part, the fixing part drives the tong head to open and close and rotate through the equipment tube, the fixing part is arranged on the robot body (1) to install surgical equipment on the robot body, and the robot body is used for providing multiple degrees of freedom for the surgical equipment;

the equipment pipe (3) comprises a driving part (31) connected with the fixing part and a driven part (32) connected with the tong head, the driving part is detachably connected with the driven part, the driving part comprises a driving pipe (311) and a driving rod (312), the driven part (32) comprises a driven pipe (321) and a driven rod (322), the driving pipe is detachably connected with the driven pipe, the driving rod is detachably connected with the driven rod, the driving pipe and the driven pipe form an outer pipe to support the tong head, and the driving rod and the driven rod form a power rod to drive the tong head to open and close and drive the tong head to rotate relative to the outer pipe;

the driven rod (322) comprises a movable cavity, a clamping part (3222) is arranged in the movable cavity, the clamping part is provided with a hinged shaft (3223) so as to hinge the clamping part on the movable cavity, the other end of the clamping part is provided with a clamping head (3224), the driving rod (312) is provided with a clamping groove (3122), the clamping head can rotate around the hinged shaft so as to enable the clamping head to be clamped into the clamping groove and further fix the driving rod and the driven rod, and the clamping head can be removed from the clamping groove so as to detach the driving rod and the driven rod, the clamping part is provided with a movable groove (3225), the driven rod further comprises a sliding rod (3226), the sliding rod is provided with a movable column (3228), the movable rod is clamped into the movable groove, and the sliding rod moves so as to enable the movable column to move in the movable groove and further drive the clamping head to rotate around the hinged shaft;

the driven rod further comprises a screw rod (3227), a central channel is formed inside the slide rod, the slide rod is connected with the screw rod lead screw through the central channel, and the screw rod is fixed on the driven rod and the driven tube and can axially rotate to drive the slide rod to move.

2. Surgical robotic surgical device according to claim 1, wherein the driven rod and the driven tube are provided with fixation holes (3211) through which screws can be passed.

3. Surgical robotic surgical instrument according to claim 2, wherein the driven rod is provided with a fixing channel for receiving the slide rod (3226), the fixing channel limiting axial rotation of the slide rod such that the slide rod is only axially movable.

4. A surgical robotic device according to claim 3, wherein the distal end of the cartridge is tapered to enable the cartridge to be received in and secured by the slot (3122).

5. A surgical robotic device as claimed in claim 4, wherein the driving link is provided with a protrusion (3121), the slot is located laterally of the protrusion, the driven link is provided with a recess, the recess communicates with the movable cavity, and the protrusion is insertable into and engageable with the recess.

6. A surgical robotic device as claimed in claim 5, wherein the recesses and protrusions are semi-circular in cross-section.