Design and kinematic analysis of 3PSS-1S wrist for needle insertion guidance

In this work it is presented a complete kinematic analysis of the 3PSS-1S parallel mechanism for its implementation as a spherical wrist for a needle insertion guidance robot. The spherical 3PSS-1S mechanism is a low weight and reduced dimension parallel mechanism that allows spherical movements providing the requirements needed for the serial–parallel robotic arm for needle insertion guidance. The solution of its direct kinematic is computed with a numerical method based on the Newton–Raphson formulation and a constraint function of the mechanism. The input–output velocity equation is obtained with the use of screw theory. Three types of singular postures are identified during simulations and verified in the real prototype. The 3PSS-1S can perform pure rotations of ±45°±45°, ±40°±40°, ±60°±60° along the View the MathML sourcex, View the MathML sourcey, View the MathML sourcez axes respectively

Study of Needle Insertion Parameters of Human Body Tissue for Surgical Operations

The thesis introduces the study on needle insertion during the laboratory experiment. The percutaneous needle insertion is performed several times in day to day life. Manually placement of needle in the tissue may cause damage inside the body sothe thesis presents the existing methodology of needle insertion and researched methodology in our laboratory. It shows the proper way of needle placement and which parameters are necessary to keep in mind when perform the needle insertion. It deals with the proper way of needle insertion, minimise the deflection of needle inside the tissue and gives an idea of reduction in deformation of tissue. The test procedures and experimental setup provide an understanding on the mechanics of needle placement and the design improvement of insertion instruments.The experimental analysis optimize the results of operative parameters of needle when it insert in the tissue like needle translation motion during the insertion, needle rotational motion during insertion, angle of needle insertion and force acting on the needle when it inserted in the tissue. The optimize results provide a brief knowledge for the surgeons about the needle behaviour during the insertion in soft tissue so surgeons are pre imagined the situations by which they would going through during the operation. The model enhances the quality of insertion by presenting the optimize model for parameters of needle insertion. In most of the insertion operations accuracy and precision is important parameters which must be kept in mind by the surgeons when they performed the insertion of needle inside the tissue so this is study is relevant for them to get the accuracy and precision in work. The aim of this research is to present standard methodology for needle insertion which can be possible by experimental analysis of needle insertion in laborator