Hyo-Jeong Cha

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The pathway to the maxillary sinus area is anatomically curved and narrow. Thus, using the conventional approach based on the straight endoscope and surgical tools, there are some limitations in inspection and treatment of the target legion of the maxillary sinus. To cope with such problems, a dual master-slave system is investigated in this work for(More)
This paper proposes a new 4-Degree-of-Freedom (DOF) master-slave system for 3 dimensional needle steering. Both master and slave devices are commonly composed of a 3 DOF spherical type parallel mechanism and a 1 DOF needle insertion mechanism. This system provides users with 3 dimensional needle steering and force reflection capabilities. The real time(More)
This paper deals with workspace analysis for a 3-RRR spatial parallel manipulator through changes of robot parameters as well as rotation angles of a ball-joint. Also, based on the tendency, the kinematic parameters and the rotation angle of the ball joint are determined to get a desired workspace.
Minimally Invasive Surgery (MIS) is usually performed in a needle insertion or a laparoscopic surgery. To minimize an incision, Remote Center of Motion (RCM) has been applied to surgery. A surgical manipulator has to be placed exactly on the RCM point during the surgery. However, a constraint force to maintain the placement exists. It may affect a patient's(More)
Recently, quite a few practical parallel mechanisms having spatial 3-DOF and 6-DOF have been introduced and implemented. However, not many useful practical applications using low-mobility parallel mechanisms having 4-DOF and 5-DOF have been developed. In this paper, we propose a 4-DOF parallel mechanism for needle insertion application in which proper(More)
The vascular intervention is performed with radioactive image guidance, so the operators are exposed to radiation. During the vascular intervention, the contrast media is injected often for providing clear images of target lesion. Repetitive injection task increases the procedure time and inconvenience. Also, accurate dosage is important to avoid the side(More)
Current vascular intervention inevitably exposes a large amount of X-ray to both an operator and a patient during the procedure. The purpose of this study is to propose a new catheter driving system which assists the operator in aspects of less X-ray exposure and convenient user interface. For this, an assembly-type 4-degree-of-freedom master-slave system(More)
Coronary artery chronic total occlusion (CTO) is one of the endovascular diseases, which is complete or almost complete blockage of a coronary artery. To remove the calcificated blockages clearly freely and precise control of catheters and guidewires are necessary for CTO treatment. The microrobot can implement drilling motion and move freely in the artery(More)
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