Motion Control Of Vascular Interventional Robotic System Based On Force Feedback For Teleoperation

The quality of the interventional vascular surgery is expected to be increasingly higher,as this kind of treatment is becoming more and more common.During an interventional procedure,doctors need to work in the X-ray environment for a long time,while the X-ray can bring damage to doctors.In order to liberate doctors from the injury of high-risk surgical environment,this robotic system can replace doctors to complete vascular interventional operation.In this system,high-accuracy motion control and the realization of force feedback are the key.The mechanical structure design and the master and slave control method of the whole robotic system are briefly described.The system is a multi-site communication system based on STM32 processor.The control scheme is designed according to the CAN bus protocol and to be the remote operation mode.The master part is the doctors' operating platform,which integrates a variety of operation methods and information feedback methods.The slave part is the implement platform,which consists of multi-manipulator and other mechanical structure.Each manipulator can complete linear motion,rotary motion and clamping motion,it meets the actual operation requirements.The introduction of the motion control method of this robotic system is represented.The clamping gripper of implement part is designed by bionics,the gripper can simulate the doctors' actual operation during surgery.The motion control methods of the clamping manipulator include brushless DC motor control scheme,stepping motor control scheme based on pulse sequence and compound motion control scheme design.The motor's PID control method is verified and improved according to the actual operation condition.At the same time,the three basic operation actions of linear motion,rotary motion and clamping motion are demonstrated.This thesis also introduces the design of compound motion,including continuous push and pull movement and continuous rotation.The motion control methods of the clamping manipulator include brushless DC motor control scheme,pulse sequence based stepping motor control scheme and compound motion control scheme design.In this thesis,the operation system principle of ?C/OS-? and the method of transplantation on STM32 are also introduced in detail.The force feedback module of robot system includes mechanical structure design and software design.In this thesis,the design scheme of force feedback structure and the realization method of force feedback software are introduced.The whole robot system test results show that the linear velocity accuracy of the manipulator can reach 0.3cm/s,the rotation accuracy can reach 1 degree,the accuracy of manipulator position control can reach 0.5mm,and the execution time of force feedback is controlled within 300 ms.Finally,the system validation of the whole vascular interventional operation robot is carried out.An experiment in vitro and an animal experiment are carried out to conduct a comprehensive test of the robot system.Compared with the same type of robot system at present,the advantages of this vascular interventional surgical robotic system are high flexibility operation space provided by multi manipulator structure,high-accuracy motion control which can improve the safety of the robot system,the embedded real-time operating system enhances the real-time of robotic system to complete complex multi tasks.The force feedback structure can greatly increase the operator's sense of presence,and the whole robot system can simulate the operation of the doctors very well.