Study Of The Operational Safety For A Vascular Interventional Surgical Robotic System

Nowadays,with the rapid development of science and technology,robots have been applied more and more widely in various fields of industry,agriculture,commerce,tourism,air and sea and national defense.People use robots to perform difficult operations that they cannot complete.In recent years,the development of robot technology in the medical field has also received extensive attention,and the birth of medical robot represents another major breakthrough in science and technology.Vascular interventional surgery robot is a typical representative of medical robots,which can not only assist doctors in performing complex operations,but also protect doctors from X-ray injuries.However,as far as the current vascular interventional surgery robot is concerned,there are still some problems need to be solved.Therefore,this paper conducts relevant studies from the perspective of improving the safety and transparency of the operation of vascular interventional surgery robot,and the specific contents are as follows:Firstly,Aiming at the problem that the structure of the slave manipulator influences the force detection of the surgical catheter,a force sensor suitable for vascular interventional surgery robot is designed in this paper.The force sensor is designed based on the full bridge circuit of the resistance strain gauge.After completing the force evaluation experiment of the internal fixture of the force sensor and the calibration experiment of the force sensor,the force sensor is mounted on the front of the slave manipulator.The aim is to directly measure the resistance of the surgical catheter in the axial movement process,eliminate the influence of mechanical transmission structure on the force detection of the surgical catheter,and improve the transparency of the operation.Secondly,this paper improved the original slave manipulator to solve the problem of large axial synchronous motion error between the master and slave side of the vascular interventional surgery robotic system.The displacement of the surgical catheter was measured by an incremental photoelectric encoder with high measurement accuracy,the displacement error of the axial synchronous movement of the master and slave side was reduced by the control method of displacement error compensation to ensure the safety of the operation.Thirdly,the vascular interventional surgery robotic system adopts the master and slave control method,which requires the doctor to operate the master manipulator to control the slave manipulator to complete the operation task.In order to solve the problem that doctors cannot obtain some important information away from patients,this paper designed an operation safety warning system for vascular interventional surgery robotic system based on LabVIEW programming language.In addition to displaying the force information of the surgical catheter and the movement information of the operation catheter,the system can also warn the operator about the current state of the surgical catheter to avoid the occurrence of blood vessel puncture by switching green(safety)indicator light,yellow(warning)indicator light and red(danger)indicator light.In addition,the system can adjust the safety threshold of blood vessel stress according to the patient's blood vessel hardness parameters,making the system more widely applied.Finally,this paper introduces the experimental platform and experimental settings in detail.The force feedback evaluation experiment of master and slave side,the force sensor test experiment,the collision force detection experiment of surgical catheter tip,the axial synchronous motion experiment of master and slave side,and the radial synchronous motion experiment of master and slave side were completed.The experiment results showed that the vascular interventional surgery robotic system had good force feedback performance with an error of less than 20 mN.The self-developed force sensor is feasible.Under the action of displacement error compensation control method,the axial synchronous motion error of master and slave side is between plus or minus 1.2 mm,and the radial synchronous motion error of master and slave side is between plus or minus 2.5 degrees.This indicates the safety operation method of the vascular interventional surgery robot is feasible and effective.