Research On The Design And Force Dragging Of Puncture Surgery Robot System With Decoupling Mechanism

Puncture surgery in tissue biopsy and tumor ablation is relatively common for diagnosis and treatment.Traditional puncture surgery requires manual operation by a specialist surgeon,In the case of multi-point puncture surgery,this work is both tedious and physically demanding.Robot-assisted puncture surgery can offer many advantages such as;improved accuracy of the punctures and a significant reduction of the manual workload for the surgeons which can ultimately result in faster recovery for the patients.Most surgery robots are cooperative in nature and consequently require a force dragging ability.According to the characteristics of puncture surgery,in this paper,a puncture surgery robot arm system with both position and orientation decoupling mechanism and force dragging function was designed for kidney biopsy.Firstly,the structural design scheme of position and orientation decoupling was analyzed.The puncture surgery robot was divided into two parts: arm and wrist.The arm is mainly used to determine the position,while the wrist is used to determine the orientation.The classical D-H convention was applied to establish the kinematics equations,the inverse kinematics analytical solution was determined,the working space of the robot was found,the Jacobian matrix was calculated,and the statics of the robot were analyzed.Generalized variables were introduced to enable the modeling of the robot as it has more joints than Do Fs.At the end of the chapter,the Matlab/Robotics Tool Box simulation tool is used for simulation verification.Then the robot parts were designed,manufactured and assembled.The software for the control structure was developed and implemented using Beckhoff Twin CAT3.It composed of the state machine of the robot and independent joint motion control based on servo control.The workflow of the robot in puncture surgery is presented and the representation form of the end puncture needle orientation was analyzed.Force dragging,for human robot interaction,on the robot operating under independent joint motion control was realized by installing a torque sensor and applying admittance control to each joint.A moving average filter was used to smooth the raw data from the joint torque sensors.The gravity moment was identified by using a static multi-input and multi-output least square method.For convenience of both analysis and implementation,a linearized interaction between the robot and the human operator was devised.A lag compensator was adopted for the admittance control strategy.Finally,MATLAB/Simulik simulation tools were used to realize the simulation verification of the force dragging admittance control.