US20230036248A1 - Endoscopy system - Google Patents

Abstract

An endoscope system is provided, which comprises an endoscope having a hollow tube formed therein, a flexible elongate member having a first end for operational control and a second distal end for operation of robotic members, one or more actuators coupleable to the flexible elongate member at the first end thereof, and an anti-buckling tube arranged with respect to the hollow tube at the first end of the endoscope to prevent buckling of the flexible elongate member during translation of the one or more actuators. Different embodiments are also disclosed, including an endoscope comprising one or more flexible tendons having a wire coil sheath which includes wire having a substantially rectangular cross section, or an endoscope comprising a rotational-motion transmitting device, one or more flexible tendons and one or more electrical wires having anti-kink support thereon, a coupling means constraining the robotic member to an asymmetric range of motion, or torque joint means comprising a centrally aligned pulley for coupling the robotic member.

Description

PRIORITY CLAIM
• The present application claims priority to Singapore patent application number 10201709245X filed on 9 Nov. 2017.
TECHNICAL FIELD
• The present invention relates generally, but not exclusively, to an endoscopy system.
BACKGROUND OF THE DISCLOSURE
• An endoscope is a hollow tube which is used to examine and/or deliver an instrument to an interior of a hollow organ or cavity of a body. For example, an endoscope can be used to examine the upper gastrointestinal tract (e.g., throat, esophagus or stomach) or the lower gastrointestinal tract (e.g. colon). The endoscope typically provides light to the internal area and provides vision for the endoscopist to navigate within the organ or cavity. Once an area is identified which needs treatment, an instrument necessary for treating the identified location is inserted into the hollow tube within the endoscope and maneuvered to the area. The instrument may, for example, be used to remove a polyp in the colon or to take a biopsy tissue sample from within the identified area for testing.
• The instrument is a flexible elongate member which is fed through the hollow tube of the endoscope to the treatment site. In order for precision operation of the instrument, it is important to prevent kinking and buckling of the flexible elongate member. In some embodiments, a coil sheath is wrapped around the cables. However, a cable with a circular coil sheath, while sufficient to transmit compressive forces, is prone to buckle or kink when there is a high amount of bending on the wire coil sheath, resulting in a narrowing of the area inside the wire coil sheath. The narrowing of the lumen due to the buckling/kinking of the wire coil sheath results in increased friction between the cable and the wire coil sheath, reducing the force transmission efficiency of the cable.
• Thus, what is needed is an endoscope device and an endoscope system for that overcomes the above drawbacks. Furthermore, other desirable features and characteristics will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background of the disclosure.
SUMMARY
• According to an aspect of the present invention, an endoscope system is provided. The endoscope system includes an endoscope, a flexible elongate member, one or more actuators and an anti-buckling tube. The endoscope has a hollow tube formed therein and has a first end coupleable to a docking station and a second distal end. The flexible elongate member is insertable through the hollow tube of the endoscope and has a first end for operational control and a second distal end for operation of robotic members at the distal end of the endoscope. The one or more actuators are coupleable to the flexible elongate member at the first end and are translatable in a direction parallel to a central axis of the hollow tube to allow fine movement of the second distal end of the flexible elongate member during operation. And the anti-buckling tube is arranged with respect to the hollow tube at the first end of the endoscope such that the flexible elongate member is inserted through the anti-buckling tube downstream of the one or more actuators to prevent buckling of the flexible elongate member during translation of the one or more actuators.
• According to a second aspect of the present invention, an endoscope system is provided which includes an endoscope and a flexible elongate member. The endoscope has a hollow tube formed therein for insertion of the flexible elongate member. The flexible elongate member has a first end for operational control and a second distal end for operation of robotic members at a distal end of the endoscope. The flexible elongate member also includes one or more flexible tendons to provide operational control from the first end to the robotic members at the second distal end, each of the one or more flexible tendons having a wire coil sheath which includes wire having a substantially rectangular cross section wound around a corresponding one of the one or more flexible tendons.
• According to a third aspect of the present invention, a flexible elongate member for use in an endoscopy system is provided. The flexible elongate member has a first end for operational control and a second distal end for operation of robotic members at the second distal end. The flexible elongate member includes one or more flexible tendons to provide operational control from the first end to the robotic members at the second distal end. Each of the one or more flexible tendons has a wire coil sheath which includes wire having a substantially rectangular cross section wound around the corresponding one of the one or more flexible tendons.
• According to a fourth aspect of the present invention, an endoscope system is provided. The endoscope system includes an endoscope and a flexible elongate member. The endoscope has a hollow tube formed therein for insertion of the flexible elongate member. The flexible elongate member has a first end for operational control and is coupled to robotic members at a distal end of the endoscope for operation thereof. The flexible elongate member includes a rotational-motion transmitting device forming a shaft of the flexible elongate member for propagating actuation from the first end to the robotic members at the second distal end.
• According to a fifth aspect of the present invention, a flexible elongate member for use in an endoscopy system is provided. The flexible elongate member has a first end for operational control and is coupled to robotic members at a second distal end. The flexible elongate member includes a rotational-motion transmitting device forming a shaft of the flexible elongate member for propagating actuation from the first end to the robotic members at the second distal end.
• According to a sixth aspect of the present invention, an endoscope system is provided. The endoscope system includes an endoscope, a flexible elongate member and at least one anti-kink support. The endoscope has a hollow tube formed therein for insertion of the flexible elongate member. The flexible elongate member has a first end for operational control and a second distal end for operation of robotic members at a distal end of the endoscope. The flexible elongate member including one or more flexible tendons to provide operational control from the first end to the robotic members at the second distal end. The at least one anti-kink support is located on one of the one or more flexible tendons to enforce a minimum bend radius on the one of the one or more flexible tendons, the anti-kink support pivoting freely about the one of the one or more flexible tendons.
• According to a seventh aspect of the present invention, an endoscope system is provided. The endoscope system includes an endoscope, a flexible elongate member, at least one robotic member and coupling means for coupling the at least one robotic member to the flexible elongate member. The endoscope has a hollow tube formed therein. The flexible elongate member is insertable through the hollow tube and has a first end for operational control and a second distal end having a camera coupled thereto. The at least one robotic member is located at the second distal end of the flexible elongate member and the coupling means couples the at least one robotic member to the flexible elongate member while constraining the robotic member to an asymmetric range of motion.
• According to an eighth aspect of the present invention, an endoscope system is provided. The endoscope system includes an endoscope, a flexible elongate member, at least one robotic member and torque joint means for coupling the at least one robotic member to the flexible elongate member. The endoscope has a hollow tube formed therein. The flexible elongate member is insertable through the hollow tube and has a first end for operational control and a second distal end. The at least one robotic member is located at the second distal end of the flexible elongate member and the torque joint means includes a centrally aligned pulley.
BRIEF DESCRIPTION OF THE DRAWINGS
• The accompanying figures, where like reference numerals refer to identical or functionally similar elements throughout the separate views and which together with the detailed description below are incorporated in and form part of the specification, serve to illustrate various embodiments and to explain various principles and advantages in accordance with present embodiments.
• FIG.1 shows a schematic illustration providing a perspective view of an endoscopy system in accordance with a present embodiment.
• FIG.2 shows a schematic illustration of a slave section of the endoscopy system ofFIG.1 in accordance with the present embodiment.
• FIG.3 shows a block diagram of modules located in either or both of a master section and a slave section of the endoscopy system ofFIG.1 in accordance with the present embodiment.
• FIG.4 shows a perspective view of a valve controller box in accordance with the present embodiment.
• FIG.5 shows an activation and/or calibration status of robotic members of the endoscopy system ofFIG.1 in accordance with the present embodiment.
• FIG.6 shows a status of a remotely-controllable valve control box from a master section of the endoscopy system in accordance with the present embodiment.
• FIG.7 shows a perspective view of the master section of the endoscopy system ofFIG.1 with position input devices (PID) and a display in accordance with the present embodiment.
• FIG.8 shows an expanded view of one of the position input devices (PID) in accordance with the present embodiment.
• FIGS.9A and9B show schematic illustrations of the components of a docking station of the endoscopy system ofFIG.1 in accordance with the present embodiment.
• FIGS.10 and11A show schematic illustrations of the docking station of the endoscopy system ofFIG.1 in accordance with the present embodiment.
• FIGS.11B and11C show structures used to realize components of the docking station of the endoscopy system ofFIG.1 in accordance with the present embodiment.
• FIGS.11D to11G show various views of a further structure used to realize components of the docking station of the endoscopy system ofFIG.1 in accordance with the present embodiment.
• FIG.12A shows a side view of a first implementation of a translation mechanism within a translatable housing ofFIGS.9A,9B,10 and11A in accordance with the present embodiment.
• FIG.12B shows a side view of a second implementation of the translation mechanism within the translatable housing ofFIGS.9A,9B,10 and11A in accordance with the present embodiment.
• FIG.13 shows a side view of a motor box to control a joint of a flexible elongate member of the endoscopy system ofFIG.1 in accordance with the present embodiment.
• FIG.14 shows a schematic of the flexible elongate member of the endoscopy system ofFIG.1 in accordance with the present embodiment.
• FIG.15 shows a cross section view of a shaft of the flexible elongate member ofFIG.14 in accordance with the present embodiment.
• FIG.16 shows a cross section view of a segment of a circular coil sheath in accordance with the present embodiment.
• FIG.16ashows a detailed cross section view of the flexible elongate member in accordance with the present embodiment.
• FIG.17 shows a cross section view of a segment of a rectangular coil sheath in accordance with the present embodiment.
• FIG.18 shows a cross section view of the segment of the circular coiled wire sheath ofFIG.16 in accordance with a second embodiment.
• FIG.19 shows a schematic diagram of an anti-kink support for electrical wires of the endoscopy system in accordance with the present embodiment.
• FIGS.20aand20bshow close-up cross-sectional views of one of the robotic members of the endoscopy system in accordance with the present embodiment.
• FIG.21ashows a side view of a pulley in accordance with the present embodiment.
• FIG.21bshows a perspective view of a torque joint with the pulley in accordance with the present embodiment.
• FIGS.21cand21dshow cross sections of the torque joint with the pulley in accordance with the present embodiment.
• FIG.21eshows a cross section of a lumen of the flexible elongate member andFIG.21fshows the cross section ofFIG.21ebeing rotated 90 degrees clockwise in accordance with the present embodiment.
• FIG.22 shows a cross sectional view of a typical hinge joint of the flexible elongate member in accordance with the present embodiment.
• FIG.23ashows a perspective view of a typical translation mechanism ofFIGS.12A and12B whileFIG.23bshows a close-up of the perspective view ofFIG.23ain accordance with the present embodiment.
• FIGS.23c,23dand23eshow cross section views of an implementation of a translation mechanism in accordance with the present embodiment.
• FIG.24ashows a perspective view of a typical electrically operated height adjustment mechanism of an endoscope docking system in accordance with the present embodiment.
• FIG.24bshows a side view of a first implementation of the slave section ofFIG.2 in accordance with the present embodiment.
• FIG.24cshows a side view of the first implementation with a disengaged electromagnetic brake when the endoscope docking system is at its highest position in accordance with the present embodiment.
• FIG.24dshows a side view of the first implementation with an engaged electromagnetic brake when the endoscope docking system is at its highest position in accordance with the present embodiment.
• FIG.24eshows a side view of the first implementation with a disengaged electromagnetic brake when the endoscope docking system is at its lowest position in accordance with the present embodiment.
• FIG.24fshows a side view of the first implementation with an engaged electromagnetic brake when the endoscope docking system is at its lowest position in accordance with the present embodiment.
• FIG.24gshows a side view of a second implementation of the slave section ofFIG.2 in accordance with the present embodiment.
• FIG.24hshows a side view of the second implementation when the endoscope docking system is at its highest position in accordance with the present embodiment.
• FIG.24ishows a side view of the second implementation when the endoscope docking system is at its lowest position in accordance with the present embodiment.
• Example embodiments of the invention will be better understood and readily apparent to one of ordinary skill in the art from the following written description, by way of example only, and in conjunction with the drawings. The drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention.
DETAILED DESCRIPTION
• In the following description, various embodiments are described with reference to the drawings, where like reference characters generally refer to the same parts throughout the different views.
• FIG.1 is a schematic illustration providing a perspective view of anendoscopy system10. Theendoscopy system10 has a master or master-side section100 having master-side elements and a slave or slave-side section200 having slave-side elements.
• With reference toFIG.2, the master section100 and theslave section200 are configured for signal communication with each other such that the master section100 can issue commands to theslave section200 and theslave section200 can precisely control, maneuver, manipulate, position, and/or operate, in response to master section100 inputs, (a) a set ofrobotic members410 carried or supported by atransport endoscope320 of theslave section200, thetransport endoscope320 having a flexible elongate shaft; (b) an imaging endoscope or imaging probe member carried or supported by thetransport endoscope320; (c) valves that are used to perform air or CO₂insufflation, water irrigation and fluid suction, the valves being coupled to passage tubes that are carried or supported by thetransport endoscope320; and (d) a probe for surgical procedures, e.g. tissue manipulation or retraction, incision, dissection and/or hemostasis, by way of one or more of electrocauterization (using an electrocautery), or lasing (using a laser), where electrical wiring connecting to the probe is carried or supported by the probe ortransport endoscope320. The master andslave sections100,200 can further be configured such that theslave section200 can dynamically provide tactile/haptic feedback signals (e.g., force feedback signals) to the master section100 as therobotic members410 are positioned, manipulated, or operated. Such tactile/haptic feedback signals are correlated with or correspond to forces exerted upon therobotic members410 within an environment in which therobotic members410 reside, such as an organism on an operating table20. Robotic members410 (seeFIG.14) refer to arms or grippers that can grab and lift tissue. Robotic members can optionally host an electrocautery probe for dissection of tissue or for hemostasis. Actuation of the arms or grippers is brought about by a cable pair (also referred to as a “tendon”, of which one is shown inFIGS.16,17 and18, denoted using thereference numeral1604. The cable/tendon may be protected by a sheath, which is not shown inFIGS.16,17 and18, but denoted usingreference numeral1602 in the cross-section view ofFIG.16a) internally located within a shaft (denoted usingreference numeral1402 inFIGS.9A,9B and14). The shaft, which may be insulated by aprotective cover1606, is used to translate and/or rotate the arms or grippers. This shaft, internally located cable pairs, and protective cover are referred to as a flexible elongate member1600 (seeFIG.16a). The cable pair serves to move joints of the arms or grippers so that therobotic members410 can grab or dissect tissue, or for other medical purposes. The actuators for the cable pair are housed in a translatable motor housing (seereference numeral926 inFIGS.9A,9B,10,11A,12A and12B) operably coupled to an adaptor (seereference numeral906 inFIGS.9A,9B and10). Thisadaptor906, theflexible elongate member1600 and therobotic members410 are referred to as a surgical instrument, whereby therobotic members410 are at the distal end of the surgical instrument.
• FIG.2 is a schematic illustration of theslave section200 of theendoscopy system10 ofFIG.1. Theslave section200 has a patient-side cart, stand, or rack202 configured for carrying at least some slave section elements. The patient-side cart202 has adocking station500 to which thetransport endoscope320 can be detached (e.g., mounted/docked and dismounted/undocked) and an associatedvalve controller box348. Thepatient side cart202 typically includes wheels204 to facilitate easy portability and positioning of theslave section200.
• FIG.3 shows a block diagram of modules located in either or both of the master section100 and theslave section200 of theendoscopy system10 ofFIG.1. The air insufflation, water irrigation and fluid suction capabilities of thetransport endoscope320 ofFIG.2 are associated with these modules. Thevalve controller box348 contains several of the modules, where thevalve controller box348 is located on the patient-side cart202 shown inFIG.2 or separate from, but in the vicinity of the patient-side cart202. The remaining modules, asafety system module352 and a motioncontrol system module354, are either located on the patient-side cart202 or attached to slave-side elements located on the patient-side cart202, such as therobotic members410 being coupled to thetranslatable housing926 that is a part of thedocking station500.
• The modules located in thevalve controller box348 include a valve box printed circuit board assembly (PCBA)364, anemergency stop PCBA362, a cart power output port356 (having a 12V rating), a valve controller box power module358 (having a 24V rating),solenoid valves360, anemergency switch366, acart power switch368 and an air/water power switch370.
• Thevalve box PCBA364 controls thesolenoid valves360 for the air insufflation, water irrigation and fluid suction functions of thetransport endoscope320. Theemergency stop PCBA362 controls thesafety system module352, which in turn controls the motioncontrol system module354. The motioncontrol system module354 controls therobotic members410.
• Thevalve controller box348 has an ACinlet power port372 which includes an AC to DC converter to provide a DC power supply to the cart power output port356 and the valve controller box power module358. The cart power output port356 and the valve controller box power module358 supply power to theemergency stop PCBA362 and the valve controller box power module358 respectively. The power is supplied to theemergency stop PCBA362 and the valve controller box power module358 when thecart power switch368 and the air/water power switch370 are switched on, respectively.
• The electrical system for the modules shown inFIG.3 is configured to have the circuitry connecting thesolenoid valves360, thevalve controller box348, thevalve box PCBA364 and the air/water power switch370 electrically isolated from the circuitry to which the remainder of the modules belong. This configuration is such that when theemergency switch366 is activated, thesolenoid valves360 will continue operating. The reason for keeping thesolenoid valves360 functioning is that activation of theemergency switch366 should not introduce any harm during a surgical operation according to medical device safety standards.
• In a first implementation, where both the cart power output port356 and the valve controller box power module358 are connected to the ACinlet power port372, the cart power output port356 and the valve controller box power module358 are on parallel electrical connections with the ACinlet power port372. Operation of theemergency stop PCBA362 is also controlled by theemergency switch366 in that activation of theemergency switch366 cuts off power to therobotic members410. This causes therobotic members410 to stop operating, while the valve controller box power module358 remains powered to allow thesolenoid valves360 to remain operating. Power cut off to therobotic members410 can be done in one of several ways, such as: terminating the connection between the cart power output port356 and the ACinlet power port372; terminating the connection between the cart power output port356 and thesafety system module352; or terminating the connection between thesafety system module352 and the motioncontrol system module354.
• In a second implementation (not shown), the cart power output port supplies power to all components of the patient-side cart of the slave section200 (seeFIG.2). In this second implementation, the cart power output port, along with its associated modules; and the valve controller box power module, along with its associated modules, are in separate enclosures. Each of these two enclosures is independently connected to the AC inlet power port so as to achieve electrical isolation.
• As the valve controller box power module358 and the cart power output port356 are independent from each other, due to the above-mentioned electrical isolation, power is still supplied to the valve controller box power module358 even after cutting off power to the cart power output port356. Thus, thesolenoid valves360 remain in operation and the air insufflation, water irrigation and fluid suction functions are unaffected, i.e. the passage tubes which are carried or supported by thetransport endoscope320 and are coupled to thesolenoid valves360 still carry air and water from thesolenoid valves360 to the organism on the operating table20 and fluid from the organism to thesolenoid valves360.FIG.3 is a schematic illustration providing a perspective view of thevalve controller box348 shown inFIG.4.
• Theemergency switch366, thecart power switch368 and the air/water power switch370 are located in the front of thevalve controller box348. Thevalve controller box348 also has ports to which thesafety system module352 is connected; position input devices (PID)702 (seeFIG.7) are connected; and a display704 (seeFIG.7).
• FromFIG.7, it will be appreciated that thePIDs702 are located at the master section100 of theendoscopy system10. ThePID702 allows movement control of therobotic members410 and activation of air insufflation, water irrigation and fluid suction functions of the solenoid valves360 (seeFIG.3) while air insufflation, water irrigation and fluid suction functions of thesolenoid valves360 can be also activated through buttons on thetransport endoscope320. With reference toFIG.8, which provides an expanded view of onePID702, eachPID702 has ahandle802 with twobuttons804. Each of three of the fourbuttons804 is assigned to provide remote control of one of the air insufflation, water irrigation and fluid suction functions of thesolenoid valves360. The fourth button is to activate teleoperation of therobotic members410. This is to make sure if the user intends to initiate teleoperation after the surgical instruments get initialized and calibrated and are ready to be remotely controlled through thePIDs702. This teleoperation initiation command can be sent through another channel such as a foot pedal.
• Before the threebuttons804 are able to control their respectively assigned air insufflation, water irrigation and fluid suction functions of thesolenoid valves360, thecart power switch368 and the air/water power switch370 have to be switched on, whereby pressing thebuttons804 will effect air insufflation, water irrigation and fluid suction. These are essential during surgery for purposes such as inflating the gastrointestinal tract, cleaning a camera lens inserted through the flexible elongate shaft of the transport endoscope320 (or embedded on the distal end of the transport endoscope320) and to remove unwanted fluid (such as from cleaning of the camera lens).
• Thedisplay704 serves to show the activation status of the remotely-controllablevalve box controller348 from thePIDs702; the calibration status of the robotic members410 (seereference numeral504 inFIG.5); the activation status of the air insufflation, water irrigation and fluid suction functions commanded through buttons on thetransport endoscope320 and/or threebuttons804 on thePIDs702. When the air/water power switch370 is switched ‘ON’ and remote control of thevalve controller box348 is activated (seereference numeral602 inFIG.6 as displayed ‘ON’ in the display704), thebuttons804 are activated to allow remote control of thesolenoid valves360. When the remote control of the valve controller box is deactivated, thedisplay704 will display the word ‘OFF’ to convey that thebuttons804 are deactivated. Thedisplay704 will also update when thebuttons804 and/or buttons on thetransport endoscope320 are pressed and provide an indication as to which of the air insufflation, water irrigation and fluid suction functions are being operated at any point of time. Together with amain display706 showing images of the air insufflation, water irrigation and fluid suction streamed by the camera lens inserted through the flexible elongate shaft of thetransport endoscope320, thedisplay704 provides an additional way for an operator to verify which of the air insufflation, water irrigation and fluid suction functions are being operated at any point of time. FromFIGS.4 to8, it will be appreciated that thevalve controller box348 provides a means to integrate operation and monitoring of air insufflation, water irrigation and fluid suction functions.
• FIG.9A shows components of thedocking station500 to which a proximal end920 of thetransport endoscope320 is attached.
• Thedocking station500 houses a motor box that contains actuators used to rotate theflexible elongate member1600 coupled at its distal end to the robotic members410 (conferFIG.14). The actuators also articulate therobotic member410 at the distal tip of theelongate member1600. The motor box is located within atranslatable housing926 that comprises a stationarylower portion930 onto which a movableupper portion928 translates. The dimension of the movableupper portion928 is larger than that of the stationarylower portion930, so that the stationarylower portion930 and the movableupper portion928 have a telescopic structural arrangement in that a portion of the stationarylower portion930 enters into or withdraws from the movableupper portion928, depending on the direction of translation of the movableupper portion928. The gap or free play between the stationarylower portion930 and the movableupper portion928 is adjusted such that foreign particles are prevented from entering into the motor box housed within thetranslatable housing926, while fluid and particles that the motor box attracts from endoscopy operation is kept outside thetranslatable housing926.
• The movableupper portion928 translates to allow therobotic members410 to allow fine movement within the organism on the operating table20.
• When the movableupper portion928 translates to push theflexible elongate member1600 further into a snugly fitted lumen within the flexible elongate shaft of thetransport endoscope320, there is a tendency for theflexible elongate member1600 to buckle as shown in the dotted portion ofFIG.9A. Further, theprotective cover1606 may be scraped off during the translation. InFIG.9A, the buckling is minimized through the use of ananti-buckling tube924 that theflexible elongate member1600 enters downstream of the motor box towards thetransport endoscope320, specifically in the exposed portion between the actuators of the motor box and the proximate end920 of thetransport endoscope320. Thisanti-buckling tube924 thus acts as a guiding member between an actuator of theflexible elongate member1600 and thetransport endoscope320. Theanti-buckling tube924 is held in place by asupport932 that extends from a portion of either a base934 to which thetransport endoscope320 docks or stationarylower portion930 of thetranslatable motor housing926. In addition, theanti-buckling tube924 is flared at both ends to facilitate straightening of therobotic members410 during insertion and removal and to prevent damage to theprotective cover1606 by sharp features at the ends of theanti-buckling tube924 during insertion and extraction of theelongate member1600, which is undertaken for example at the end of a surgical procedure, or when switching to a new surgical instrument of a different function. Theanti-buckling tube924 may be realized using rigid structures, such as a pipe.
• This buckling of theelongate member1600 is further minimized through the implementations shown inFIGS.9B,10 and11A, as further described below.
• The first implementation ofFIG.9B further alleviates the above buckling and scrape off problems by having at least aportion1420 of theshaft1402 rigid, theportion1420 being adjacent to where theflexible elongate member1600 attaches to theadaptor906.
• FIGS.10 and11A show a sketch of a second implementation of thedocking station500 to which a proximal end920 of thetransport endoscope320 is attached, this second implementation seeking to alleviate the buckling of theflexible elongate member1600 shown inFIG.9A.FIG.10 shows the movableupper portion928 in a fully extended state, whileFIG.11A shows the movableupper portion928 during translation.
• While the first implementation uses a singleanti-buckling tube924, the second implementation uses twoanti-buckling tubes1024aand1024b.The twoanti-buckling tubes1024aand1024bhave a telescopic structural arrangement in that one of the twoanti-buckling tubes1024aand1024bhas a larger dimension than the other, where when the movableupper portion928 of thetranslatable housing926 translates, theanti-buckling tube1024a,1024bwith the smaller dimension enters into theanti-buckling tube1024a,1024bwith the larger dimension. InFIGS.10 and11A, it is shown that theanti-buckling tube1024ahas a smaller dimension and acts as an inner guide, while theanti-buckling tube1024bhas a larger dimension and acts as an outer guide. However, it is also possible that theanti-buckling tube1024ahas a larger dimension, while theanti-buckling tube1024bhas a smaller dimension. It will be appreciated that in the second implementation ofFIGS.10 and11A, it becomes optional to make a portion of theflexible elongate member1600 rigid.
• Theanti-buckling tube1024ais held in place by asupport1032athat protrudes from the movableupper portion928, while theanti-buckling tube1024bis held in place by asupport1032bthat protrudes from a portion of either the base934 to which thetransport endoscope320 docks or the stationarylower portion930 of thetranslatable motor housing926. When the movableupper portion928 translates, theanti-buckling tube1024awill also translate. By eliminating relative translation movement between theanti-buckling tube1024band theelongate member1600, wearing down of theprotective cover1606 is reduced. Similar to theanti-buckling tube924 ofFIGS.9A and9B, the duo pieceanti-buckling tube1024aand1024bis flared at its ends to facilitate removal of therobotic members410. In both the first and second implementations, the singularanti-buckling tube924 and the duo pieceanti-buckling tube1024aand1024bis detachable from thedocking station500 for sterilization or for replacement with a new singularanti-buckling tube924 and a new duo pieceanti-buckling tube1024aand1024b.
• FIGS.9A,9B,10 and11A show that thetranslatable housing926 has a substantially vertical orientation, with the movableupper portion928 undergoing vertical translation to move theflexible elongate member1600. However, it will be appreciated that thetranslatable housing926 may be placed in other orientations (not shown), such as a horizontal one, whereby the movable portion translates in a substantially horizontal manner, or an inclined one, whereby the movable portion moves along an inclined axis.
• Theanti-buckling tubes1024aand1024bcan become soiled during use. Thus, it is advantageous that they be designed to be cleaned and sterilized in place or otherwise be removable for cleaning separately so that they can be reused. Alternatively, theanti-buckling tubes1024aand1024bmay be designed for single-use and disposable, in which case a fresh tube is supplied for each procedure.
• If theanti-buckling tubes1024aand1024bare designed to be reused, the material of theanti-buckling tubes1024aand1024bshould be chosen to ensure compatibility with the prescribed cleaning and sterilization method. As a wide range of cleaning and sterilization solutions are in use in different regions of the world, a material with broad compatibility across multiple solutions is advantageous. As such, corrosion resistant metals such as stainless steels or corrosion resistant polymers are good material choices for theanti-buckling tubes1024aand1024b.
• If theanti-buckling tubes1024aand1024bare designed for operable decoupling from thetranslatable motor housing926 during cleaning and sterilization, an attachment means facilitating decoupling of theanti-buckling tubes1024aand1024bfrom thetranslatable motor housing926 should also facilitate ease and thoroughness of cleaning and/or sterilization. Many possible cleanable attachment means are conceivable. For example, attachment means that use magnets are particularly advantageous as they can be embedded leaving a smooth, flat, or convex outer profile with few, if any, crevices to ease cleaning by brush or wipe down with a cloth. In one implementation, thesupports1032aand1032bare manufactured using magnetic material or at least have embedded magnets, whereby thesupport1032ais welded to theanti-buckling tube1024aand thesupport1032bis welded to theanti-buckling tube1024b.
• FIGS.11B and11C show structures that use non-magnetic means such as mechanical means to attach anti-buckling tubes to thetranslatable motor housing926 ofFIGS.9A,9B,10 and11. Non-magnetic means are employed in scenarios where magnets used in thesupports1032aand1032b(seeFIGS.10 and11A) may interfere with the operation of magnetic components within thetranslatable motor housing926.
• If magnetic attachment of theanti-buckling tubes1024aand1024bis not possible a dynamic-engagement mechanism1135 shown inFIG.11B may be used. The dynamic-engagement mechanism1135 has abody9 having a first opening to accommodate at least a portion of ahandle6 of theanti-buckling tube7. Thebody9 houses a mechanical catch arrangement that releases theanti-buckling tube7 from thebody9 when theanti-buckling tube7 is to be removed for cleaning. In the implementation shown inFIG.11B, the mechanical catch arrangement comprises arod2, anabutment member3, arelease button1 and a biasingstructure5. Therod2 is pivotally connected to theabutment member3 and therelease button1 and is disposed to move along a longitudinal section of thebody9. Thebody9 has a second opening through which a portion of therelease button1 protrudes from thebody9; while a portion of therelease button1 that is within thebody9 is coupled to the biasingstructure5. A membrane/impermeable barrier4 covers the portion of therelease button1 that protrudes from thebody9.
• When therelease button1 is operated through the membrane/impermeable barrier4, theabutment member3 is mechanically activated in the direction shown in the arrow, whereby therod2 pulls theabutment member3 downwards. Thehandle6, which is welded to theanti-buckling tube7, is released in thedirection8. The membrane/impermeable barrier4 can be permanently attached to thebody9 or removable for cleaning and sterilization.
• FIG.11C shows a variant of the implementation shown inFIG.11B. The dynamic-engagement mechanism1135 ofFIG.11C is the same as the dynamic-engagement mechanism1135 ofFIG.11B. However, instead of using a membrane/impermeable barrier4, thebody9 of the dynamic-engagement mechanism1135 ofFIG.11C uses adynamic seal4″ to seal thebody9 from soiling. Thedynamic seal4″ may be, for example, a washer where frictional engagement between the wall of the second opening of thebody9 through which thebutton1 protrudes and a facing surface of thedynamic seal4″ hinders fluid from entering thebody9 internal cavity.
• FIGS.11D to11G depict yet another variant of the couple of theanti-buckling tubes1340 to theanti-buckling tube holder1342 which can be achieved through mechanical means using non-permanent plastic deformation properties of theanti-buckling tube1340. Theanti-buckling tube1340 comprises a portion of compliance feature/geometry1344 which can temporarily deform to be fitted into the rigid portion of theanti-buckling tube holder1342. Theanti-buckling tube1340 can either be attached/detached to theanti-buckling tube holder1342 in a perpendicular direction to themotor housing face1350 or the angle ofattachment1349 can be at an acute angle to themotor housing face1350. In addition, three or moresided faces1346 on the compliance feature/geometry1344 enables acentral plane1348 of theanti-buckling tube1340 to always be perpendicular to themotor housing face1350. This allows the flexible elongate member to be inserted through theanti-buckling tube1340.
• FIG.12A shows a first implementation of the translation mechanism within thetranslatable housing926 ofFIGS.9A,9B,1011A and11B, whileFIG.12B shows a second implementation of the translation mechanism within thetranslatable housing926 ofFIGS.9A,9B,1011A and11B. In bothFIGS.12A and12B, the housing is not shown. The translation mechanism of thetranslatable housing926 comprises a motor (denoted usingreference numeral1202 inFIG.12A andreference numeral1204 inFIG.12B) and a lead screw mechanism or ball screw mechanism (denoted usingreference numeral1222 inFIG.12A andreference numeral1224 inFIG.12B). Theoverall height926hof thetranslatable housing926 is affected by the configuration of the translation mechanism (which comprises a motor and lead screw mechanism or ball screw mechanism) of thetranslatable housing926 as explained below.
• InFIG.12A, themotor1202 that drives the translation motion is mounted on theplatform1220 and translates together with theplatform1220. As theplatform1220 translates, theheight926hof thetranslatable housing926 varies between the fully retracted state and the fully inserted state of thelead screw mechanism1222.
• Alow height926his desirable because it eases docking of the drive mechanism of therobotic members410 on theplatform1220. A portion of the drive mechanism, namely an instrument adaptor (which contains drums around which the cable pair shown inFIGS.16,17 and18 wind at the proximate end), is shown inFIGS.9A,9B and10 and denoted using thereference numeral906.
• In the configuration ofFIG.12B, thetranslation motor1204 that translates theplatform1220 is mounted onto a stationary bracket. The platform1220 (on which the housing of the movableupper portion928 is placed) is allowed to translate by being mounted to amember1226 that is rotatably coupled to thelead screw mechanism1224 driven by thetranslation motor1204. Thismember1226 may be an object with a hole, such as a nut.
• For the same range of translation motion, theheight926hof thetranslatable housing926 ofFIG.12B will be lower than that ofFIG.12A as thescrew mechanism1224 ofFIG.12B does not translate, whereas thescrew mechanism1222 of themotor1202 ofFIG.12A translates while it is being driven by themotor1202.
• There are crevices between theoutput shaft chassis1304 and amotor output shaft1302. If there is fluid ingress into such a crevice, it would pose a risk or a malfunction to the fluid sensitive components around theoutput shaft1302.
• Ashield1306 is fitted around theoutput shaft1302 between the fluid sensitive components and an internal wall of theoutput shaft chassis1304. This shield repels fluid that ingresses into the crevices and thus prevents the ingressed fluid from coming into contact with the fluid sensitive components. Theshield1306 is particularly advantageous over using a shaft seal to prevent such fluid ingress, whereby use of the shaft seal around theoutput shaft1302 introduces friction to the shaft rotation.
• FIG.14 shows a schematic of aflexible elongate member1600 that is coupled at its distal end to therobotic member410 and at its proximal end to a drive mechanism. The drive mechanism consists of a series of mechanical linkages that transmit motion from actuators to the adaptor906 (FIGS.9A and9B). Theadaptor906 contain motivators, for example one or more drums, around which a cable pair winds that allow movement control of therobotic members410, the cable pair running within theflexible elongate member1600. In one implementation, a motor box containing one motor shaft (seereference numeral1302 ofFIG.13) is used to rotate theflexible elongate member1600 to which therobotic members410 are connected.
• As theflexible elongate member1600 has to effectively propagate actuation that is applied at its proximal end to the distal end (such as rotation or a translation), a part of it,shaft1402, may be realized using a rotational-motion transmitting device, such as a torque coil, that possesses low rotational backlash, good torque transmission, and low compressibility. The rotational-motion transmitting device also must be flexible enough to conform to thetransport endoscope320. To achieve this mix of properties, the rotational-motion transmitting device used for theshaft1402 is designed to incorporate one or more of the following features.
• A first feature uses a flat coil, of which onesegment1502 is shown inFIG.15. From the cross-section view, the longer portion W of the coil is lain such that when the flat coil is wound edge to edge, it forms the longitudinal length of theshaft1402. Example cross section dimensions for the flat coil is a width W of 0.2-0.4 mm and a thickness T of 0.05-0.15 mm. Contact between adjacent coils in the longitudinal direction transmit compressional forces with low backlash. Also, thinner layers enable the luminal space to be larger for a given outside diameter constraint, thus flat wire coils are preferable to round wire coils for a given number of layers within the coil.
• A second feature uses multiple layers of a flat coil manufactured in accordance with the first feature. The direction of winding alternates between layers, which makes the resulting shaft402 deliver 1 to 1 torque with less backlash. For example, the section cutout1504 shown inFIG.15 has threelayers4,5 and6. Theinner layer4 and theouter layer6 are wound in the same direction, e.g., S rotation also known as left hand winding direction, while themiddle layer5 is wound in the other direction, the Z rotation also known as right hand winding direction. Each layer consists of 8-12 strands of flat wire wound in a helix, which results in the outside diameter of the coil ranging from 3 mm to 6 mm.
• Alternating the direction of winding between layers results in 1 to 1 rotation between the proximal and distal ends with low backlash in the following way. When transmitting torque in a given direction, the left-hand wound coil or coils will introduce rotational backlash by expanding their diameter. Under the same direction of twist, right hand wound coil or coils will introduce rotational backlash by reducing their diameter. When coils of alternating wind directions are layered inside of each other, this source of rotational backlash is prevented. In the example above, the radial expansion of the left-hand wound coil is counteracted by the radial compression of the right-hand wound coil in the next outer layer. A minimum of three layers of alternating wind direction coils is required to eliminate this source of rotational backlash in both directions.
• FIG.16 shows a cross section view of a segment of a circular coil sheath, in accordance with a known implementation, where the circular coil sheath has acircular wire coil1602 with acable1604 running through its lumen. Such circular wire coil sheaths are used to transmit compressive forces. Thecable1604 running inside thewire coil1602 lumen provides tensile force in an action reaction pair. Low friction between these two components is desirable to prevent transmission loss of the tensile force. In the case of conduits that impose a high amount of bending on thewire coil1602 sheaths, even small compressive forces applied to thewire coil1602 sheath will cause it to buckle/kink, resulting in a narrowing of the lumen of the wire coil sheath. The narrowing of the lumen due to the buckling/kinking of the wire coil sheath results in increased friction with thecable1604, reducing the force transmission efficiency of thecable1604.
• FIG.16ashows a detailed cross section view of a flexible elongate member1600 (as shown inFIG.14) including aprotective cover1606, ashaft1402, a number ofcircular coil sheaths1602 andcable1604 contained within eachcircular coil sheath1602.
• For simplicity, only four pitches ofwire coil1a-1dare shown inFIG.16. Thecompressive forces4a,4bon1bcome fromadjacent pitches1aand1c.When the circular coil sheath is bent, this compressive force has an upward component. There is a counteractingdownward force5 from the tendency of thewire coil1602 to retain its original shape. There is also a smalldownward force6 exerted by thecable1604 on1b.However, when the compressive force from4a,4bis great enough, the circular surfaces where1binterfaces with1aand1cform an unstable equilibrium whereby an incremental slip of1bin the upward direction causes the angle of contact between adjacent pitches to change markedly. This in turn leads the direction of thecompressive reaction forces4a,4bbetween adjacent pitches to change markedly. This in turn causes even more upward lateral slip of1bin a virtuous cycle and leads to permanent deformation of the coil, known as buckling/kinking. This instability can propagate along the length of a sheath, as shown inFIG.18.
• FIG.17 shows a cross section view of a segment of a rectangular wire coil sheath, in accordance with an improvement over the circular coil sheath ofFIG.16. The rectangular wire coil sheath has awire coil1702 with a substantially rectangular cross section. Similar to the circular coil sheath ofFIG.16, acable1604 runs through the lumen of the rectangular coil sheath ofFIG.17.
• The improvement overFIG.16 is that instead of a coil wire with a circular cross section, acoil wire1702 with a rectangular cross section is used. When it is wound into a sheath, each pitch of the sheath has more stable contact with the adjacent pitches, such that external bending and compressive forces on the wire coil are less likely to cause the alternating pitches to slip in the lateral direction. The rectangular cross section is shorter in the direction of the wire coil sheath. This increases the pitch density, which results in a smaller amount of bending per pitch and hence an induced strain in the cross-section due to bending that is lower than induced strain of a lower pitch density coil under the same radius of bend. If the induced strain from bending and compressional forces is kept below the yield strain for the material, there will be no permanent buckling/kinking of thewire coil1702. A slight movement upwards ofcoil3bdoes not change the angle of attack of the compressive force fromcoils3aand3c.With a smaller pitch, the change in angle of attack is further reduced, leading to better anti-buckling performance thancircular wire coil1 while retaining the same bending properties.
• A particular embodiment of the rectangular coil sheath is when the cross section has equal dimensions, i.e. it is a square coil sheath. This does not provide the benefits of increased pitch density, but still provides more stability against buckling because the angle of attack of the compressive force fromcoils3aand3con3bdoes not change with lateral deflection. Also, a square cross section coil has a greater cross-sectional area than the circular cross-sectional area of a circular wire coil of equivalent pitch. This makes it more resistant to lateral shear forces.
• FIG.18 shows a similar cross section view of the segment of the circular coiled wire sheath ofFIG.16. In this figure, the coiledwire sheath1802 is made of a super-elastic material. One example of a super-elastic material is nitinol, an alloy of Nickel and Titanium. Nitinol has unique material properties in that it can be deformed to a large extent by loading but is still able to recover its original shape after the load is removed. InFIG.18, a nitinol circular coiledwire sheath1802 is highly compressed during periods of high loads on thecable1604, and thus it undergoes temporary buckling. This increases the friction on cable1604 (as shown inFIG.16 andFIG.16a), and reduces efficiency. After the coiledwire1802 is unloaded/unbent, the coiledwire1802 reverts to its original shape instead of remaining in the plastically deformed irregular shape. Hence, the coiledwire sheath1802 may be operating at maximum efficiency for most of the time, without a degradation of efficiency over time.
• FIG.19 shows a schematic diagram of ananti-kink support1902 for electrical wires. The anti-kink support may be located at arobotic member410 and may increase the kink resistance of the wire1604 (seeFIGS.14 and16a) without affecting the function of a rotational joint. It can be appreciated that, in addition to the tendons/cable1604, the shaft also carries electrical wires (not shown inFIG.16afor the sake of simplicity), As shown in theFIG.19, theanti-kink support1902 of the current invention enforces a minimum bend radius on thewire1604 by havingcurved inlets1906. The minimum bend radius is determined experimentally such that wire does not experience bending fatigue failures within the expected life of the device, while minimizing the space required inside the device to accommodate the wire bending. Theanti-kink support1902 includessupports1908 that allow it to pivot freely onpins1910aand1910bor similar non-pin shaped structure. This may allow thewire1604 to achieve its energetically most stable state, i.e. possessing the lowest amount of total bending. The axis of rotation of theanti-kink support1902 may be substantially co-located with the axis of articulation of therobotic member410, such that the wire does not experience appreciable stretch or compressional forces throughout the articulation range of motion of therobotic member410.
• FIG.20ashows a close-up cross-sectional view of one of therobotic members410 according to an example embodiment. Therobotic member410 may have asymmetric ranges of motion such that there is enhanced visibility by the camera, which may lead to safer operation of the instrument. Thejoints2006 of therobotic member410 are allowed to move in a smaller angle in the direction away from the camera axis than in the direction towards the camera axis through the use ofmechanical hardstops2008a,2008b,2010a,2010b.Alternative embodiments may involve the use of software and position sensing to achieve the same effect.
• In an example embodiment, therobotic member410 ofFIG.20ais shown with three stages of articulation, i.e. at neutral position (0°), 90° anticlockwise of the neutral position and 45° clockwise of neutral position. The base joint2002 is fixed and is parallel to the axis ofreference2012. The distal joint2004 rotates about thehinge2006. The upper hardstops2008aand2008bprovide the maximum degree of upward rotation allowed. In an example embodiment as shown, a maximum of 90° anticlockwise rotation about the neutral position is permitted. The surface of lower hardstops2010aand2010bmay have a different angle as compared to surfaces of hardstops2008aand2008bsuch that the maximum degree of downward rotation is limited. In an example embodiment as shown, a maximum of 45° clockwise rotation about the neutral position is permitted. The cumulative effect of the asymmetry across multiple joints may determine the workspace at the distal end of therobotic member410. The asymmetries among the joints can be optimized to provide maximum visibility of thedistal end effector2014.
• In an example embodiment, an implementation of the above concept is shown inFIG.20bin conjunction with acamera2016 adjacent to arobotic member410. Therobotic member410 lies substantially parallel to the viewing direction of the camera, but with a small lateral offset2020. When therobotic member410 is articulated away from thecamera2016, the mechanical hardstops2010a,2010blimit the motion of thedistal end effector2014 from going too far out of the visual range.
• The endoscopy system may include a torque joint located at the robotic instrument that makes use of a centrally aligned pulley with space saving sheet metal structural components and which does not use a central pin. Such a torque joint occupies as little cross-sectional space as possible yet provides the maximal amount of torque for a given cable force by centrally aligning the pulley so that the pulley's diameter may be maximized for a given diameter of therobotic member410. Further, the torque joint allows pass-through elements to be routed without obstruction along both sides of the pulley. Using sheet metal to mount the centrally aligned pulley and transmit its torsional forces to the rest of the torque joint may allow thinner walls compared with other mounting solutions for a comparable manufacturing cost and hence a more compact pulley structure can be obtained. As the pulley is no longer directly connected to the hinge joints, a locating pin may be used temporarily during assembly to maintain a good alignment between the rotational axis of the pulley and the rotational axis of the torque joint.
• FIG.21ashows a side view of apulley2102 whileFIG.21bshows a perspective view of the torque joint with thepulley2102. Thepulley2102 may include triangular sheetmetal mounting brackets2116aand2116b.Thepulley2102 may also contain features2118a-2118dthat assist in retaining the pulley wire. Thesheet metal components2106 may help to constrain theactuating wire2108 and also structurally fix thepulley2102 to the distaljoint section2110. The hinge joints2104aand2104bprovide points of rotation for the distaljoint section2110 and are axially aligned with thepulley2102.FIGS.21cand21dshow a cross section of the torque joint with thepulley2102. In the Figures, thelumen2112 is bisected due to the centrally alignedpulley2102.
• FIG.21eshows a cross section of thelumen2112 andFIG.21fshows the same cross section being rotated 90 degrees clockwise according to an example embodiment. In the Figures, the configuration reserves space for thepulley2102 without encumbering the pass-through elements2114 (not shown inFIG.21e). A centrally aligned pulley allows its diameter to be as large as possible, which increases the mechanical advantage of the joint. The absence of a central rivet pin means that thelumen2112 is not excessively dissected, which would have reduced lumen cross sectional area available for the pass-throughelements2114. The torque joint of the current invention may also allow the pass-throughelements2114 to undergo less severe bending when the joint is articulated.
• FIG.22 shows a cross sectional view of a typical hinge joint2202. The joint2202 may include aproximal segment2204 and adistal segment2206 and may be positioned at the robotic member410 (as shown inFIG.14). Rotation occurs around the point where both theproximal segment2204 and thedistal segment2206 overlap. In a preferred embodiment as shown, both thesegments2204,2206 may be constrained using twoseparate rivet pins2208aand2208b.This may enable the internal luminal space2210 to be reserved for other uses.
• A clearance fit exists between thepins2208a,2208bandjoint segments2204 and2206 that allows smooth rotation of the joint. However, such a clearance may prevent the ease of aligning the pivot axes of the twosegments2204,2206. If the segments are misaligned, there may be difficulty in movement at the extreme ranges of motion. Hence, thepins2208a,2208bmay be aligned with each other by means of abridging insert2212. Thus, a method may be provided to ensure axial alignment of the two discrete hinge joints through the use of a bridging insert during assembly. The bridging insert can either become part of the joint or can be extracted. In an embodiment as shown inFIG.22, theinsert2212 may be a rod that runs through holes in the rivet pins2208a,2208band thus may ensure that the segments are aligned. After the rivet pins2208a,2208bhave been welded to theproximal segment2204 to create a retained joint, thebridging insert2212 is removed.
• In endoscope systems, where a translation actuator is used to translaterobotic members410 in and out of the transport endoscope320 (seeFIG.2, whereby therobotic members410 are introduced into thetransport endoscope320 through its proximal end920, seeFIG.9A), it is advantageous that the translation actuator remains fixed in position when power is removed from the translation actuator. In systems where the translation actuator is back-drivable under expected external forces like gravity or other forces, therobotic members410 will move in or out of thetransport endoscope320 when power is removed from the actuator. This is especially disadvantageous when uncommanded translation motion of therobotic members410 causes therobotic members410 to come into unintentional contact with sensitive tissue. Thus, it is advantageous that the translation actuators of endoscopic systems be non-back drivable when powered down.
• FIG.23ashows a perspective view of a typical translation mechanism of whileFIG.23bshows a close-up of the perspective view of the typical translation mechanism. Typical translation actuators often employ low friction drive mechanisms, such asball screws2322 to convert rotary motion of anelectric motor2302 tolinear motion2326 of the actuator. Ball screws2322 are preferred in the industry for the low friction that is consumed, which gives repeatable motion for a given input command.Typical ball screws2322 include rolling contact elements instead of sliding contact elements and have long service lives due to low wear rates. However,typical ball screws2322 have at least two characteristics that make them unsuitable for use as translation actuators in an endoscopic system. Firstly, the low friction rolling elements ofball screws2322 make them back-drivable at forces that are often lower than the expected external loads. Secondly, decreasing the pitch of theball screw2322 increases its back-driving resistance. The amount that the ball screw pitch can be lowered is limited as compared to other transmission elements. This is because sufficient room must be reserved in between adjacent pitches to accommodate the rolling elements and their reciprocating guide races.
• FIGS.23c,23dand23eshow cross section views of an implementation of atranslation mechanism2300 that may improve the back-drivability of current industrial linear actuators. As shown in theFIGS.23cto23e, an endoscopicsystem translation mechanism2300 includes arotary motor2304 and alead screw2306 to convert rotary motion of themotor2304 into translation motion of the robotic members410 (referFIG.2). Alead screw2306 is used in this embodiment as it has inherently more friction due to the sliding contact between thelead screw2306 and alead screw nut2308 as compared to a ball screw, which has low friction rolling element contact. In addition, alead screw2306 can have lower pitch than an equivalently sized ball screw, giving thelead screw2306 more back-driving resistance. Thetranslation mechanism2300 may also include astationary motor platform2310 for enclosing themotor2304 and amotor platform base2312 to support thetranslation mechanism2300.FIGS.23dand23eshow various positions of thelead screw nut2308 translated vertically as themotor2304 rotates thelead screw2306.
• In an alternative embodiment not shown in the figures, thetranslation mechanism2300 may include a rotary motor and a ball screw, such that the motor has sufficient internal gear reduction to provide the required back driving resistance. Such an embodiment may be favorable where the higher friction and lower service life of a lead screw are unacceptable in thetranslation mechanism2300. A preferred embodiment of such a motor would include a planetary gear reduction or a harmonic drive, both of which allow for large gear reduction ratios in compact sizes.
• A further embodiment of thetranslation mechanism2300 may include a motor, a ball screw, and an electrically operated friction device that automatically engages to stop motion of the actuator when power is removed from the motor. Such an embodiment may be favorable when the higher friction and lower service life of a lead screw are unacceptable, and where a large gear reduction within the motor would result in an unacceptably slow translation speed. The preferred embodiment of such a friction device is a rotary electromagnetic brake connected to the motor shaft or the ball screw.
• An endoscope docking system may include thedocking station500, thetransport endoscope320 and the associated valve controller box348 (as shown inFIG.2). It is advantageous to adjust a height of the endoscope docking system to accommodate different patient table heights as well as different clinician heights. In addition, it is also advantageous to secure the endoscope docking system once it is adjusted to a desirable height. Due to safety reasons, the endoscope docking system must remain secure at the desirable height to avoid sudden and unexpected changes during endoscopy.
• There are currently a variety of simple mechanisms that could provide an adjustable height function for the endoscope docking system. One example of such a mechanism includes a simple bolting interface with multiple bolting locations of different heights that provides adjustability but may require the use of tools to perform the adjustment and an extra person to support the weight of the mechanism while it is being adjusted. This makes adjustment of a bolting interface during the procedure cumbersome and impractical. Other adjustable height mechanisms such as a mechanically operated vertical screw adjuster or a mechanically operated hydraulic lift cylinder may be employed. It is however impractical to locate the mechanical control of these devices near the user's hand location on the control body of the attached endoscope or near the user's foot due to the large number of mechanical linkages required to transmit the motion to the desired location. This means that the user must stop what they are doing and move over to the position of the controls and then move back to their original location to assess whether the adjustment was sufficient. This adds delay and inconvenience to the user.
• Another solution may include the use of an electrically operated actuator to adjust the height of the endoscope docking system based on inputs from the user via a control interface.FIG.24ashows a perspective view of a typical electrically operated height adjustment mechanism of anendoscope docking system2402. Theelectric actuator2404 in this mechanism must reliably support and manipulate the entire weight of theendoscope docking system2402. Due to the large size and weight of theendoscope docking system2402, the cost of theelectric actuator2404 is also high. Thus, even though an electrically operatedactuator2404 gives more freedom on the location of the user controls, but it also adds significant cost to the endoscopy system.
• Herein disclosed are mechanisms that may eliminate the inconvenience of existing mechanical adjustment mechanisms and may provide a lower cost than electric actuator systems. The mechanisms disclosed may include a weight compensation device and an electrically-operated locking device. The weight compensation device may offset the majority of the weight of the endoscope docking system. The remainder of the weight is flexibly hung so as to be easily vertically adjustable without straining. The weight compensation device may also include a height adjustment mechanism to adjust the height of the endoscope docking system.
• The electrically-operated locking device may include a controller and user controls. Being electronic, the user controls can be located near to hand or foot locations, e.g. with reference toFIG.7, near thePID702 or foot pedals of the master section. The preferred user controls consist of either a hand-operated button, or a foot-operated switch. The devices default to the locked state and are only unlocked during activation of the user controls.
• FIG.24bshows a side view of theslave section200 ofFIG.2 incorporating a weight compensation device and an electrically-operated locking device, both in accordance with a first implementation. As shown in theFIG.24b, theslave section200 includes the patient-side cart202, anendoscope docking system2406, aheight adjustment mechanism2408 and a linearelectromagnetic brake2410. Theendoscope docking system2406 includes thedocking station500 and the transport endoscope320 (as shown inFIG.2). In this implementation, theheight adjustment mechanism2408 may include a constant force spring from which theendoscope docking system2406 is directly hung. The force of the constant force spring is customized to be substantially similar to the weight of the endoscope docking system's2406 heaviest configuration.
• As shown inFIG.24c, theendoscope docking system2406 is at its highest position with the linearelectromagnetic brake2410 disengaged. This allows height adjustment of theendoscope docking system2406 by theheight adjustment mechanism2408 while maintaining the weight of theendoscope docking system2406.
• FIG.24dshows theendoscope docking system2406 at its highest position with the linearelectromagnetic brake2410 engaged. After theendoscope docking system2406 is adjusted to a desirable height, the engaged linearelectromagnetic brake2410 firmly secures theendoscope docking system2406 to avoid sudden and unexpected changes during endoscopy which may endanger the patient. More specifically, the linearelectromagnetic brake2410 may directly engage theendoscope docking system2406 using friction to prevent vertical movement of theendoscope docking system2406.
• Theslave section200 may include a linear electromagnetic engaging spline or ratchet (not shown in the Figures) that directly engages theendoscope docking system2406 using interlocking components to prevent vertical movement of theendoscope docking system2406. Examples of interlocking components include actuators, gears and/or valves.FIGS.24eand24fshow theelectromagnetic brakes2410 at the disengaged and engaged positions respectively when theendoscope docking system2406 is at its lowest point.
• FIG.24gshows a side view of theslave section200 ofFIG.2 incorporating a weight compensation device and an electrically-operated locking device, both in accordance with a second implementation. As shown in theFIG.24g, theslave section200 includes the patient-side cart202, anendoscope docking system2406 and aheight adjustment mechanism2408. Theendoscope docking system2406 includes thedocking station500 and the transport endoscope320 (as shown inFIG.2).
• In this second implementation, theheight adjustment mechanism2408 may be a counter-weight and pulley system, where thecounterweight2412 is substantially similar in weight to theendoscope docking system2406. An elongateflexible member2414 connects thecounterweight2412 to theendoscope docking system2406 in a way such that the elongateflexible member2414 is routed up and over saidpulley2416. Theelongate member2414 may be inelastic and may be made of anti-slip material so that there is no slippage between theelongate member2414 and thepulley2416 as thedocking system2406 undergoes vertical motion. Preferred embodiments of thepulley2416 and elongateflexible member2414 may consist of either a cog tooth belt and a cog tooth pulley, or a chain sprocket and a chain. In addition, theheight adjustment mechanism2408 may include a rotational electromagnetic brake (not shown) that is applied to thepulley2416 to which theelongate member2414 engages.FIGS.24hand24ieach respectively show an implementation of the counterweight and pulley system when theendoscope docking system2406 is at its highest position and lowest position.
• It will be appreciated by a person skilled in the art that numerous variations and/or modifications may be made to the present invention as shown in the embodiments without departing from a spirit or scope of the invention as broadly described. The embodiments are, therefore, to be considered in all respects to be illustrative and not restrictive.

Claims (20)

1.-13. (canceled)

14. An endoscope system comprising:

an endoscope having a hollow tube formed therein; and

a flexible elongate member for insertion through the hollow tube, wherein the flexible elongate member has a first end for operational control and a second distal end for operation of robotic members at a distal end of the endoscope, the flexible elongate member including one or more flexible tendons to provide operational control from the first end to the robotic members at the second distal end, wherein each of the one or more flexible tendons has a wire coil sheath, the wire coil sheath comprising wire having a substantially rectangular cross section wound around the corresponding one of the one or more flexible tendons.

15. The endoscope system in accordance withclaim 14 wherein the one or more flexible tendons comprise one or more cable pairs wrapped in the wire coil sheath.

16. The endoscope system in accordance withclaim 14 wherein the wire coil sheath comprises wire having a substantially square cross section wound around the corresponding one of the one or more flexible tendons.

17. The endoscope system in accordance withclaim 14 wherein the substantially rectangular cross section of the wire coil sheath is shorter in a direction of the wire coil sheath.

18. The endoscope system in accordance withclaim 14 wherein the wire coil sheath comprises a super elastic material.

19. The endoscope system in accordance withclaim 18 wherein the super elastic material is nitinol.

20. A flexible elongate member for use in an endoscopy system, the flexible elongate member having a first end for operational control and a second distal end for operation of robotic members at the second distal end, the flexible elongate member comprising:

one or more flexible tendons to provide operational control from the first end to the robotic members at the second distal end, wherein each of the one or more flexible tendons has a wire coil sheath, the wire coil sheath comprising wire having a substantially rectangular cross section wound around the corresponding one of the one or more flexible tendons.

21. The flexible elongate member in accordance withclaim 20 wherein the one or more flexible tendons comprise one or more cable pairs wrapped in the wire coil sheath.

22. The flexible elongate member in accordance withclaim 20 wherein the wire coil sheath comprises wire having a substantially square cross section wound around the corresponding one of the one or more flexible tendons.

23. The flexible elongate member in accordance withclaim 20 wherein the substantially rectangular cross section of the wire coil sheath is shorter in a direction of the wire coil sheath.

24. The flexible elongate member in accordance withclaim 20 wherein the wire coil sheath comprises a super elastic material.

25. The flexible elongate member in accordance withclaim 24 wherein the super elastic material is nitinol.

26.-40. (canceled)

41. The endoscope system in accordance withclaim 15 wherein the wire coil sheath comprises a super elastic material.

42. The endoscope system in accordance withclaim 16 wherein the wire coil sheath comprises a super elastic material.

43. The endoscope system in accordance withclaim 17 wherein the wire coil sheath comprises a super elastic material.

44. The flexible elongate member in accordance withclaim 21 wherein the wire coil sheath comprises a super elastic material.

45. The flexible elongate member in accordance withclaim 22 wherein the wire coil sheath comprises a super elastic material.

46. The flexible elongate member in accordance withclaim 23 wherein the wire coil sheath comprises a super elastic material.

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