Design And Analysis Of A Hydraulic Driven MRI-Compatible Breast Intervention Robot

MRI has better definition of soft tissue,MRI-guided breast interventional surgery has attracted much attention due to its minimally invasive and accurate.Because MRI has its unique features,such as limited internal space,material selection requires the use of nuclear magnetic compatible materials,etc.This paper proposes the use of hydraulic driven MRI-compatible breast interventional robots to achieve compatibility between the drive device and MRI.This article first analyzes the design requirements of MRI-compatible breast intervention robots,and determines the overall design plan.Due to the need to be compatible with the MRI environment,we use polytetrafluoroethylene and nonmagnetic stainless steel materials to product the parts needed for the robot.When designing the robot,the modular design ideas were adopted,namely the rotationcontraction breast tissue fixation mechanism,the rectangular coordinate-based positioning mechanism,the pitch joint and the biopsy mechanism,and the 3D model of the MRI-compatible breast intervention robot was established using Solid Works software.Secondly,according to the three-dimensional model of the MRI-compatible breast intervention robot established above,a link coordinate system is created for each joint link of the robot.Solve the positive and inverse solutions by means of a homogeneous transformation matrix.In MATLAB/Simulink software,the Sim Mechanics toolbox is used to build a simulation model to solve the working space of the robot end point and verify that its working space meets the design requirements.Then,the stress components of this MRI-compatible breast intervention robot are analyzed,and finite element analysis is performed in ANSYS / Workbench software,including stress and strain analysis.The analysis results provide a theoretical basis for the rationality of the robot structural design.Using 3D printing technology to make a physical model of MRI-compatible breast intervention robot,assemble and debug it.Use this physical model to verify the workspace,and prove the correctness and rationality of the workspace obtained by simulation in MATLAB.In the end,because the hydraulic drive was used to meet the compatibility of the driving device and the nuclear magnetic environment,experimental research on the positioning error of the hydraulic drive was carried out,which established a theoretical basis for the subsequent control research of the robot.