Research On The Simulation Of Robot Assisted Vascular Puncture

Compared with traditional vascular suture operation, robot-assisted operation has the advantages of operational stability and high positioning accuracy, which can achieve a better stitch of minor-diameter vascular, on the other hand, the disadvantages such as the eye-hand discoordination and the lack of tactile information. The most frequently used method is end to end intermittent suture, including operations such as needle holding,needle manipulating, puncturing and suturing among which the vascular puncturing is the most fundamental operation. Surgeons need to do massive training before the robotassisted vascular suture operation, but the cost of traditional training methods is high. To cut down the training cost and improve training results, this paper launches researches on techniques of the simulation of robot-assisted vascular puncturing.In this paper, nonlinear mass-spring model is adopted to build the vascular deformation model. By introducing bending force and moment we improved the nonlinear massspring model and derived the kinematic equation. Based on the model, two simulation models of vascular deformation in different topologies were built, the single layer square topological structure vascular model and the single layer diamond topological vascular model. A comparative analysis between the two models was made in this paper.In order to approximate the mechanical response of the real vascular the using the virtual vascular model, the parameters of the simulation model of vascular deformation are optimized. The disadvantage of this model is that it is difficult to determine the parameters. To address this problem, firstly we determined some parameters and tested the parameters whether they can ensure the stability of the model through programming.Then the results and the parameters were taken as the training set, and based on the set we can predict the parameter set which can ensure the stability of the model through Gaussian Process Classification. At last, aiming at making the biomechanical properties of the vascular model approximate the real vascular, we got the optimized parameters of the vascular model by using Gaussian Process Regression.The master-slave control methods of the virtual surgical robot executing mechanism and the method for needle aspiration of vascular are studied in this paper. The 3 mobile and 3 rotational DOF of the main operating hand are mapped to the end of the robot. By solving the inverse kinematics, the position and attitude of the actuator is determined, and the master-slave motion of the end effector of the main manipulator and the virtual surgery robot is realized. The hierarchical bounding box method is used to perform collision detection between the end effector of the robot and the needle, realizing the needle holding and manipulating through the actuator. An adaptive particle swarm algorithm is proposed,in which we introduced 12 movable particles to realize the interaction between the needle and the vascular model in the process of vascular puncturing.Finally, the robot-assisted simulation experimental platform of vascular puncturing was set up to verify the feasibility of the master slave motion method for virtual surgical robot actuator and the needle aspiration method. In order to enhance the reality of the operation and improve doctor’s feeling of immersion during the operation, the augmented reality technology is introduced into the simulation of robot-assisted surgery. Through integrating CHAI3 D and ARTool Kit, realizing the coordination of the registration between the two, finally we carried out a demonstration experiment to verify the effectiveness of the method.