Robotics in endoscopic surgery: can mechanical manipulators provide a more simple solution for the problem of limited degrees of freedom?

The minimally invasive nature of endoscopic surgery allows operations to be performed through small incisions, producing significantly less damage to good tissue than in conventional open surgery. Patient recovery times are thus greatly reduced. This major advantage has driven a dramatic growth of endoscopic techniques in a wide range of surgical applications. Unfortunately, the surgeon's abilities are severely hampered by the limitations of current endoscopic technology. In many ways endoscopic surgery is similar to teleoperation of a remote manipulator. Although the surgeon is physically close to the patient, the surgical environment is effectively “remote,” with sensing and manipulation transmitted through the endoscope and long instruments. Existing solutions from teleoperation applications could likely be applied to endoscopic surgery. This paper attempts to identify the major problems of current endoscopic technology, particularly in vision and manipulation. Vision issues are discussed in the first half, motivated by an experiment comparing surgeons' performance under different visual conditions. Surgeon subjects perform a three-dimensional positioning task with binocular direct vision, monocular direct vision, and a video endoscope. The lack of a stereoscopic view through the endoscope significantly slows performance of the tasks, but there are additional factors that make endoscopic viewing worse than monocular direct viewing. Relevant previous results which demonstrate the significance of interocular spacing in stereo viewing and the effect of display-control axes misalignment are also discussed. Issues of endoscopic manipulation are discussed in the second half of this paper, motivated by a suturing task comparing surgeons' performance with hand and endoscopic instruments. The constraint of endoscopic instruments' passing through the skin reduces their usable degrees of freedom and significantly increases the time to tie a suture knot. Kinematics of endoscopic instruments are compared to the human hand and arm. A model of the surgeon's precision grasp demonstrates the role of stiffness in fine motion control as an example of an advantage of the hand which is lost in the use of endoscopic instruments. The work described in this paper represents an initial effort in identifying problems and evaluating solutions in endoscopic surgery based on objective measurement of performance.

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Design of an Adjustable Table Mount for Multifunctional NOTES Robot

2017 Design of Medical Devices Conference ◽

10.1115/dmd2017-3329 ◽

2017 ◽

Author(s):

Shannon Fischer ◽

Tao Shen ◽

Carl Nelson ◽

Dmitry Oleynikov

Keyword(s):

Endoscopic Surgery ◽

Degrees Of Freedom ◽

Natural Orifice ◽

End Effector ◽

Surgical Method ◽

Limited Space ◽

External Incisions

Natural orifice transluminal endoscopic surgery (NOTES) is a method in which tools are passed through a natural orifice to the surgical site. This removes the need for external incisions, which can allow patients to recover more quickly without any visible abdominal scarring. This surgical method also has several limitations including limited space, complex lumen geography, and difficult visualization [1]. To address these problems, researchers have developed various tools, including endoscope-based robots [2], and insertable bimanual robots [3]. However, some of the aforementioned constraints/limitations remain, and consideration of accessories for use with these tools remains relevant. Our lab designed a multifunctional NOTES robot, which consists of a snakelike linkage driven by cables that are attached to motors in an external housing to navigate through the lumen geometry; it also includes a bimanual end effector with interchangeable tool tips [4]. This paper introduces the design of an adjustable table mount to address the limitations related to transluminal insertion. It provides four passive degrees of freedom (DOFs) to grossly place the robot, and enables the robot to be fixed on surgical tables with different sizes. Benchtop testing on a surgical table with a patient mannequin demonstrates its functionality.

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Preliminary Report of Multi Degrees of Freedom Forceps for Endoscopic Surgery

Surgical Laparoscopy Endoscopy & Percutaneous Techniques ◽

10.1097/00129689-200404000-00004 ◽

2004 ◽

Vol 14 (2) ◽

pp. 66-72 ◽

Cited By ~ 7

Author(s):

Shinsuke Usui ◽

Haruhiro Inoue ◽

Tatsuya Yoshida ◽

Shin Kudo ◽

Takehisa Iwai

Keyword(s):

Endoscopic Surgery ◽

Preliminary Report ◽

Degrees Of Freedom

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A Specimen Extraction Instrument Based on Braided Fiber Tube for Natural Orifice Translumenal Endoscopic Surgery

Journal of Medical Devices ◽

10.1115/1.4040638 ◽

2018 ◽

Vol 12 (3) ◽

Cited By ~ 1

Author(s):

Jinhua Li ◽

Zemin Zhang ◽

Shuxin Wang ◽

Zufeng Shang ◽

Guokai Zhang

Keyword(s):

Endoscopic Surgery ◽

Mechanical Model ◽

Degrees Of Freedom ◽

Geometric Model ◽

Natural Orifice ◽

Specimen Extraction ◽

Channel Diameter ◽

Suction Cup ◽

Narrow Space ◽

Promising Development

Natural orifice translumenal endoscopic surgery (NOTES) has offered significant advantages of less pain, reduced recovery time, and minimized scar after operation, demonstrating a promising development prospect. However, the large-size specimen extraction remains challenging for NOTES, due to the narrow space of the human natural orifices. To address such difficulties, a specimen extraction method that utilizes the braided fiber tube (BFT) structure with excellent retractility to accommodate and bind the bulky specimen has been proposed. Based on the theory of helical spring, the geometric model and the mechanical model of the BFT are established, and experiments have been performed to verify the accuracy of the derived mechanical model. In addition, a tensile test of using the BFT to extract large specimens via a small channel is carried out, which verifies the stable extraction performance of the proposed design. The BFT will not be damaged when extracting the specimen with a diameter less than 1.75 times of the channel diameter. A NOTES-specific specimen extraction instrument is designed according to the characteristics of NOTES, and it has three degrees-of-freedom and is able to actively capture different specimen by using a suction cup. Finally, specimen extraction experiments on NOTES multitasking platform phantom have been conducted using the prototyped instrument to validate its feasibility and effectiveness.

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A SIMPLE SOLUTION FOR THE FLAVOR QUESTION

Modern Physics Letters A ◽

10.1142/s0217732396002630 ◽

1996 ◽

Vol 11 (32n33) ◽

pp. 2639-2647 ◽

Cited By ~ 37

Author(s):

FELICE PISANO

Keyword(s):

Standard Model ◽

Gauge Group ◽

Degrees Of Freedom ◽

New Physics ◽

Simple Solution ◽

Next Generation ◽

The Standard Model ◽

Low Energies

We consider a simple way of solving the flavor question by embedding the three-family standard model in a semisimple gauge group extending minimally the weak isospin factor. Quantum chiral anomalies between families of fermions cancel with a matching of the number of families and the number of color degrees of freedom. Our demonstration shows how the theory leads to determination of families structure when the standard model is the input at low energies. The new physics is limited to start below a few TeVs within the reach of the next generation colliders.

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The motion of a lunar orbiter

Symposium - International Astronomical Union ◽

10.1017/s0074180900105686 ◽

1966 ◽

Vol 25 ◽

pp. 373

Author(s):

Y. Kozai

Keyword(s):

Degrees Of Freedom ◽

Dimensional Space ◽

Artificial Satellite ◽

Equations Of Motion ◽

Triaxial Ellipsoid ◽

The Moon ◽

Secular Motion ◽

The Earth ◽

Close Satellite ◽

The Mean

The motion of an artificial satellite around the Moon is much more complicated than that around the Earth, since the shape of the Moon is a triaxial ellipsoid and the effect of the Earth on the motion is very important even for a very close satellite.The differential equations of motion of the satellite are written in canonical form of three degrees of freedom with time depending Hamiltonian. By eliminating short-periodic terms depending on the mean longitude of the satellite and by assuming that the Earth is moving on the lunar equator, however, the equations are reduced to those of two degrees of freedom with an energy integral.Since the mean motion of the Earth around the Moon is more rapid than the secular motion of the argument of pericentre of the satellite by a factor of one order, the terms depending on the longitude of the Earth can be eliminated, and the degree of freedom is reduced to one.Then the motion can be discussed by drawing equi-energy curves in two-dimensional space. According to these figures satellites with high inclination have large possibilities of falling down to the lunar surface even if the initial eccentricities are very small.The principal properties of the motion are not changed even if plausible values ofJ3andJ4of the Moon are included.This paper has been published in Publ. astr. Soc.Japan15, 301, 1963.

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Representing utility and deploying the body

Behavioral and Brain Sciences ◽

10.1017/s0140525x19001602 ◽

2020 ◽

Vol 43 ◽

Author(s):

David Spurrett

Keyword(s):

Functional Activity ◽

Degrees Of Freedom ◽

The Body ◽

Target Article ◽

Processing Demands ◽

The Many

Abstract Comprehensive accounts of resource-rational attempts to maximise utility shouldn't ignore the demands of constructing utility representations. This can be onerous when, as in humans, there are many rewarding modalities. Another thing best not ignored is the processing demands of making functional activity out of the many degrees of freedom of a body. The target article is almost silent on both.

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An Attack on the Contamination Problem in the Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061859 ◽

1967 ◽

Vol 25 ◽

pp. 368-368

Author(s):

J. J. Kelsch ◽

A. Holtz

Keyword(s):

Electron Microscope ◽

Pressure Gradient ◽

Ionization Potential ◽

Simple Solution ◽

Specimen Surface ◽

Contamination Rate ◽

Local Pressure ◽

High Ionization ◽

Hydrocarbon Molecules ◽

Contamination Problem

A simple solution to the serious problem of specimen contamination in the electron microscope is presented. This is accomplished by the introduction of clean helium into the vacuum exactly at the specimen position. The local pressure gradient thus established inhibits the migration of hydrocarbon molecules to the specimen surface. The high ionization potential of He permits the use of relatively large volumes of the gas, without interfering with gun stability. The contamination rate is reduced on metal samples by a factor of 10.

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