Design Of Line Driven Continuum Surgical Robot For Minimally Invasive Surgery

The use of surgical robot in doctor's operations on patient is becoming more and more widespread.Surgical robot has high efficiency,small incisions,and stable operation.It is difficult to meet these requirements with traditional normal surgery.Because traditional surgical robot is composed of rigid joint links,poor motion flexibility and large space.Traditional surgical robot cannot operate freely and flexibly in the natural cavity and minimally invasive incision of the human body.The operation of a line driven continuum surgical robot that has good bending ability and work in a narrow nonlinear environment becomes an important research direction.In this paper,a line driven continuum surgical robot system for minimally invasive surgery is designed in the context of a narrow nonlinear space environment.Firstly,the need of surgical robot in a narrow nonlinear surgical environment is analyzed,and a line driven continuum surgical robot mechanical system is designed.The system combines UR series robot arm,Stewart parallel robot platform,line driven continuum end effector,Phantom haptic force feedback equipment,including the end effector drive and the control frame.Secondly,according to the motion characteristic of serial robot,parallel robot,and continuum robot,the kinematics analysis of the surgical robot system is performed.The forward and inverse kinematics analysis of the UR manipulator in the surgical robot system is performed.The kinematics of the manipulator is simulated in the Robotics Toolbox.Different DH parameter is changed to achieve different space pose.The forward and inverse kinematics analysis of the Stewart parallel robot platform is performed.The parallel platform is modeled and kinematically simulated in SimMechanics.The displacement of the parallel platform is output.The forward kinematics and inverse kinematics analysis on the continuum end effector is performed,including kinematics analysis of single joint segment and multi joint segment.The kinematics simulation in MATLAB environment is performed,the result shows that the continuum end effector can move freely and flexibly in space.Then,the finite element simulation of the surgical robot system in the Ansys environment is performed.The modal analysis of the parallel platform with frequent vibration is performed on free and constrained mode.The static analysis of the parallel robot platform in the horizontal and vertical direction is performed to verify the force situation under extreme condition.A static analysis is performed on the joint unit of the continuum end effector.An explicit dynamic analysis is performed on the continuum end effector to analyze its force under the collision interference condition.Finally,the workspace of the surgical robot system is solved.The workspace of the UR manipulator is calculated by the Monte Carlo method,the simulation result shows that the workspace of the manipulator can meet the rough positioning function of the surgical robot system.The boundary search algorithm is used to calculate the position and attitude workspace of the parallel platform,the simulation result shows that the parallel platform can meet the precise positioning function of the surgical robot system.The workspace of the continuum end effector is calculated by the Monte Carlo method,the simulation result shows that the continuum end effector can meet the operation function of the surgical robot system in the narrow nonlinear environment.