Mechanism Design And Control Research On A Mri-compatible Minimally Invasive Robot

This paper is focused on the Magnetic Resonance Imaging (MRI) compatible needle insertion robot for prostate needle insertion surgery. A series of work for the whole robotic system is put out, which contains material selection, mechanism design, kinematic analysis, control system design and so on. Additionally, a simulation experiment on soft-tissue is held on to aid the research on soft tissue finite element analysis method and trajectory planning in soft tissue. The following work has been completed:Firstly, with the account for the characteristic of MRI, confined space, prostate needle insertion surgery, polyformaldehyde (POM) is selected as the main material for this robot prototype. A synthesis of air cylinders and ultrasound motor is adopted to realize the function of needle body orientation and needle tip insertion respectively. And then, a robot mechanism design is presented after a thought of robotic performance and surgery characteristic. A robot with three stages is built in software SOLIDWORKS, and each stage can realize different functions to achieve the surgery.Secondly, base on the robot mechanism design, a forward and inverse kinematic analysis is introduced, which ensures the correctness of mechanism design in theory by forward deduction, and puts out a method to calculate actuators position following the optimized trajectory. And its performance, workspace, controllable ability all fulfill the design requirements.Finally, a robotic control system is built, which contains position collection module and vision module. The cooperation of these modules helps the control of the system. Additionally, an experiment is held to verify the correctness of the robotic system.