Study On Subclavian Vein Puncture Robot And Puncture Force Model

In clinical,central venous catheterization(CVC)is a kind of widely used puncture operation.It can not only rapid fluid replacement and monitor intravenous pressure,but also give patients parenteral nutrition and drug injection.Due to the lack of necessary theoretical support and selection of puncture parameters in the puncture process,the success of CVC heavily depends on the doctors.With the growing maturity of robotics technology,more and more robots are used in treatment.In this paper,a active and passive hybrid robot for subclavian vein puncture is designed.The puncture force model is established and the factors affecting the puncture force are studied.Operative process of CVC was analyzed for the design criteria of puncture machine.Base on functional analysis,SCARA robot is selected as the prototype,and the degree of freedom is added to satisfy the operation requirements.The shortest rod length of the robot is obtained according to optimization design of minimum size;The puncture module can adjust the puncture angle and puncture speed;The end workspace of the robot is analyzed by MATLAB,and the stiffness of the robot under gravity is analyzed by ANSYS software.Both results show that the designed robot meets the application requirements of the CVC.In order to achieve high-precision puncture and provide theoretical basis for the puncture process,the puncture force is divided into four parts:rigid force,cutting force,friction force and vascular puncture force based on the analysis of soft tissue process and human anatomical structure.According to the contact theory in elasticity,the rigid force model is constructed;according to the energy theory in linear elastic fracture mechanics,the cutting force model is obtained;the interaction principle between needle and tissue is analyzed by using the knowledge of friction pile and material mechanics in civil mechanics,and the friction force model is established;according to the fact that blood vessel is a kind of pipe.The model of vascular puncture force was established by mechanics of piping.The experimental platform of puncture vessel is designed and built to analyze the puncture force of similarities and differences between different biological tissues and simulated tissues.The parameters affecting puncture force are divided into three categories:puncture method,geometric parameters of needle and biological tissues.Those parameters are studies by experiment.Response surface is established based on experimental data,and the influence of puncture force on multi-dimensional parameters is analyzed.To a certain extent,the selection of puncture parameters under different puncture conditions is guided.