Mechanism Design And Human-robot Interaction Of Endoscopic Surgery Robot

The Remote Center of Motion(RCM)of the slave manipulator arm of the surgical robot is one of the core components of the Minimally Invasive Surgical(MIS)robot system.The mechanical structure design of the RCM directly affects the performance of the MIS robot,but also restricts the development and design of other components in the robot system.In this paper,the structure design,kinematics analysis,gravity compensation and human-robot interaction of the active arm of the MIS robot,as well as the simulation analysis and performance verification of the operation movement are carried out in detail.Firstly,the mechanical structure of endoscopic surgery robot is designed in detail.Based on the analysis of the research status of the RCM at domestic and foreign,a novel of RCM is proposed by considering the advantages and disadvantages of all kinds of RCM.The synchronous belt is used to replace the traditional double parallelogram RCM small arm to build a novel RCM mechanism,inheriting the double parallelogram RCM with high positioning precision and the double synchronous belt RCM with compact structure and high bearing capacity.Secondly,a complete kinematic model is constructed.Based on the D-H parameter method,the kinematics equation of the RCM of the active arm of the endoscopic surgery robot is constructed.To solute of inverse kinematics and the Jacobian matrix of the velocity.Based on MATLAB,Monte Carlo method is used to solve the workspace of the active arm,and Sim Mechanics method is used to solve the workspace of the active arm.The workspace of the active arm constructed by novel RCM,which is solved by numerical method and simulation method,is compared and analyzed to meet the operation requirements.Thirdly,the gravity compensation analysis of the manipulator arm is carried out.In order to establish the active arm of the surgical robot to realize the human-robot interaction control,the gravity compensation method is proposed to compensate the gravity of the active arm,and the virtual simulation model is built by ADAMS to analyze,and compare the change of the motion performance before and after the gravity compensation,The change of driving torque and end positioning accuracy of the RCM,Verifies the feasibility of gravity compensation by using the combination of Tension spring-rope pulley,improves the reverse driving ability of the active arm,and lays a foundation for human-robot interaction of the active arm of slave manipulator.The algorithm model based on fuzzy reinforcement learning is used to control the human-robot interaction of the active arm.The simulation results show that the variable admittance control model based on fuzzy learning can realize the flexible and natural positioning operation of the arm,which can meet the needs of damping changes in each stage of the human-robot interaction process,and has high controllability and stability.Finally,the virtual operation of the robot's active arm of the slave manipulator is completed.Based on ADAMS,a virtual simulation model of the active arm of the slave manipulator is built to simulate the minimally invasive operation with the active arm.The movement stability and positioning accuracy of the endoscope were analyzed when the RCM of the active arm was rolling,pitching and moving.Furthermore,when the RCM is in the joint motion of roll and pitch,the output torque of the drive motor is measured,and the angular velocity and centroid velocity of the endoscope are measured.The cause of the delay of the surgical instrument is analyzed and the method of calculating the delay of the endoscope motion is proposed.The simulation results show that the active arm of endoscopic surgery robot based on the novel RCM can fulfill the requirements of minimally invasive surgery.