Hoseok Song

A Novel Surgical Manipulator with Workspace-Conversion Ability for Telesurgery

This paper proposes a surgical manipulator with workspace-conversion ability for both minimally invasive surgery (MIS) and open surgery. The focus of the proposed surgical manipulator is on its potential use in places such as battlefields, army camps, and rural areas rather than in civilian hospitals. The proposed surgical manipulator has a workspace for MIS with a virtual remote center of motion and has a workspace for open surgery like that of an articulated manipulator. The mechanism of the surgical manipulator is proposed and implemented in this paper. A new distal rolling joint with two spiral wire ropes is also implemented. Several experiments to validate the feasibility of the surgical manipulator were carried out. Two fundamentals of laparoscopic surgery tasks were performed to compare the performance of the surgical manipulator with other MIS systems. The workspace conversion from MIS to open surgery was implemented. The workspace-conversion ability enables the surgical manipulator to attach or detach the surgical tool unit without human assistance or an assistant robot.

Development of optical fiber Bragg grating force-reflection sensor system of medical application for safe minimally invasive robotic surgery.

Force feedback plays a very important role in medical surgery. In minimally invasive surgery (MIS), however, the very long and stiff bars of surgical instruments greatly diminish force feedback for the surgeon. In the case of minimally invasive robotic surgery (MIRS), force feedback is totally eliminated. Previous researchers have reported that the absence of force feedback increased the average force magnitude applied to the tissue by at least 50%, and increased the peak force magnitude by at least a factor of two. Therefore, it is very important to provide force information in MIRS. Recently, many sensors are being developed for MIS and MIRS, but some obstacles to their application in actual medical surgery must be surmounted. The most critical problems are size limit and sterilizability. Optical fiber sensors are among the most suitable sensors for the surgical environment. The optical fiber Bragg grating (FBG) sensor, in particular, offers an important additional advantage over other optical fiber sensors in that it is not influenced by the intensity of the light source. In this paper, we present the initial results of a study on the application of a FBG sensor to measure reflected forces in MIRS environments and suggest the possibility of successful application to MIRS systems.

Sequence‐specific termination by T7 RNA polymerase requires formation of paused conformation prior to the point of RNA release

The sequence‐specific, hairpin‐independent termination signal for the bacteriophage RNA polymerases in Escherichia coli rrnB t1 terminator consists of two modules. The upstream module includes the conserved sequence and the downstream one is U‐rich.

The Development of human-arm like manipulator for Laparoscopic Surgery with Force sensing

This paper describes design of the dexterous manipulator for laparoscopic surgery that performs like a human whole arm and the FEM simulation result to measure the force of its tool-tip to include force-feedback loop for the future. Though a human whole arm has 7 degrees of freedom, we have designed overall 8 degrees of freedom because of considering one dof translation motion that corresponds with human body movement. Some researchers reported that if we could develop either mechanical or electromechanical tele-operators which enable surgeons to move a MIS system in a manner analogous to an open instrument, we could potentially reduce the time of current laparoscopic procedures by at least 15% and we could perhaps also enable surgeons to perform procedures which are thought currently too difficult to execute. Accordingly, we are expecting that the suggested design provides surgeon with improved dexterity during minimally invasive surgery.

Development of the dexterous manipulator and the force sensor for Minimally Invasive Surgery

This paper describes the design and the performance results of a dexterous manipulator for Minimally Invasive Surgery (MIS) that performs like a human arm. The design of the loadcell to measure the force of its tool-tip and its method are also presented for including a force-feedback loop in the future. Because a human whole arm has 7 degrees of freedom (DoF), we have also designed 7 DoF manipulator. Some researchers reported that the development of either mechanical or electromechanical teleoperators, which would enable surgeons to move a MIS system in a manner analogous to an open instrument, the time of current laparoscopic procedures could potentially be reduced by at least 15%. Furthermore, it is also possible that surgeons would be able to perform procedures currently considered too difficult to execute. Additionally, improved haptic Information is a helpful to perform the surgery safer and faster. Accordingly, we are expecting that the suggested design will provide surgeons with improved dexterity and advanced haptic feeling during minimally invasive surgery.

Design and Evaluation of a Teleoperated Surgical Manipulator with an Additional Degree of Freedom for Laparoscopic Surgery

This paper describes a teleoperated surgical manipulator with an additional degree of freedom (d.o.f.). If the surgical manipulator has the same number of d.o.f. as a human arm, intuitive movements of the surgical manipulator will be achieved and the movements of the surgical manipulator will be easily predictable. The proposed surgical manipulator affords 7-d.o.f. joints using a cable–pulley mechanism. The surgical manipulator has upper and lower arms akin to a human arm, and has an elbow joint as an additional d.o.f. joint. In addition, a remote controller was developed to measure the human arm position and deliver the angle data of the 7-d.o.f. joints to the surgical manipulator by TCP/IP communication. The calculated joint angles from the remote controller have a linear relationship with the measured angles from a human arm. The tracking experiment was performed and an approach angle to the surgical site was measured using a liver model. The proposed manipulator has a wider angle range compared to that of a conventional surgical tool. The surgical manipulator can also perform surgical tasks near the bottom of the liver model.

A Teleoperated Minimally Invasive Surgical System with an Additional Degree of Freedom Manipulator

A teleoperated minimally invasive surgical system was implemented for laparoscopic surgery. The surgical manipulator has upper and lower arms akin to a human arm and has an elbow joint as an additional DoF joint. A remote controller was developed to measure the human arm position and deliver the angle data of the human arm to the surgical manipulator by TCP/IP communication. The human elbow angle change is used to activate the additional DoF joint of the surgical manipulator. The tooltip of the surgical manipulator has a wide approach angle from below the liver model toward the upper part of this model.

Development of optical FBG force measurement system for the medical application

Haptic feedback plays a very important role in medical surgery. In minimally invasive surgery (MIS), however, very long and stiff bar of instruments take haptic feeling away from the surgeon. In minimally invasive robotic surgery (MIRS), moreover, haptic feelings are totally eliminated. Previous researchers have reported that the absence of force feedback increased the average force magnitude applied to the tissue by at least 50%, and increased the peakforce magnitude by at least a factor of two. Therefore, it is very important to provide haptic information in MIRS. Recently, many sensors are being developed for MIS or MIRS, but they have some obstacles in their application to real situations of medical surgery. The most critical problems are size limit and sterilizability. Optical fiber sensors are one of the most suitable sensors for this environment. Especially, optical fiber Bragg grating (FBG) sensor has one additional advantage than the other optical fiber sensors. FBG sensor is not influenced by intensity of light source. In this paper, we would like to present the initial results of study on the application of the FBG sensor to measure reflected forces in MIRS environments and then suggest the possibility of successful application to the MIRS systems.

The Dexterous human-arm like manipulator for Laparoscopic Surgery

This paper describes design of the dexterous manipulator for laparoscopic surgery that performs like a human whole arm and the FEM simulation result to measure the force of its tool-tip for including force-feedback loop. Though a human whole arm has 7 degrees of freedom, we have designed overall 8 degrees of freedom because of considering one dof translation motion that corresponds with human body movement. Some researchers reported that if we could develop either mechanical or electromechanical tele-operators which enable surgeons to move a MIS system in a manner analogous to an open instrument, we could potentially reduce the time of current laparoscopic procedures by at least 15% and we could perhaps also enable surgeons to perform procedures which are currently too difficult. Accordingly, we are expecting that the suggested design provides surgeon with improved dexterity during minimally invasive surgery.