Study On Stability And Position Planning Of 5-DOF Single-incision Laparoscopic Surgery Robot

With the improvement of robot technology in recent years,robot related technology has been gradually applied to various scientific fields.Medical robots have become a new field of modern medical operation.Especially in the field of minimally invasive surgery,robot assisted minimally invasive surgery occupies a place.The control system can perform very meticulous operation and improve the flexibility and accuracy during the operation,which is different from the traditional minimally invasive operation mode.As an important branch of the auxiliary operating robot,the laparoscopic robot is the integration of many disciplines,such as machinery,electronics,medicine,automation and so on.It can provide a clear vision in the abdominal cavity and facilitate the operation of ninimally invasive surgery.Because of the initial stage of the domestic laparoscopic robot systel,a kind of single-incision laparoscopic surgery robot is put forward in the present situation of the development of the laparoscopic surgery robot system at home and abroad,and the related research and analysis are carried out.First,conbining with the related knowledge of celiac operation,the design requirements of single-incision laparoscopic surgery robot are proposed.The configuration of the robot is analyzed and selected.A robot with 5-DOF hybrid is designed according to the selected configuration structure,and the structure of a single-incision laparoscopic surgery robot is constructed with the finite element soft ANSYS.Static analysis and modal analysis were carried out to obtain the static performance of single-incision laparoscopic surgery robot.Secondly,according to the characteristics of the robot's mechanism,the kinematics analysis of the robot is carried out by D-H method,and the positive solution of the motion equation of the robot is obtained.The geometry method is used to obtain the position coordinates of the endoscope at the end of the base coordinate system and the position coordinates of each joint in the terminal coordinate system of the endoscope,and then the inverse solution of the robot is obtained.The Jacobian matrix of the robot is obtained by the linear transformation relation between the generalized velocity and the joint velocity.The simulation of the kinematic model are also carried out.The working space of the robot is derived according to the kinematic equations of the robot,and the singularity of the robot is analyzed by the condition number of Jacobian matrix,and the effect of each joint in the robot on the dexterity of the robot is analyzed.According to the mechanism of the robot,the stiffness model of various mechanisms is calculated and the model of the whole static stiffness is derived,and the influence of each joint on the static stiffness of the robot is analyzed.Then,the Kane method is used to establish the dynamics model of the robot,and the equations of driving force and driving torque of each motor in the robot are obtained.According to the motion timing of each mechanism of the robot,the mechanism motion plan with different timing is put forward.Numerical simulation and virtual simulation are carried out with MATLAB and ADAMS respectively.The influence of the motion plan of different mechanisms on the speed and angular velocity of endoscope,and the change values of the driving force and driving torque of the related mechanism are obtained,which provides the basis for the dynamic stability analysis of the robot.Finally,by using the improved gradient projection method,the position planning model of the single-incision laparoscopic surgery robot is carried out,the relative position planning model is established,and the angle value of the joint under different pendulum positions is obtained.The pendulum position of the endoscope is analyzed by the position planning model,and the space position simulation is carried out by MATLAB.Thus,the optimal position planning of the single-incision laparoscopic surgery robot is obtained.Based on the research of the stability and position planning of the robot,it provides a theoretical basis for the clinical application of the single-incision laparoscopic surgery robot,improves the accuracy of the abdominal operation,and thus achieves the purpose of minimally invasive surgery and is of great significance to the extensive application of the robot in the abdominal operation.