Study On Surgeon Training System For Vascular Interventional Surgery Robot Based On Visual Presence

At present,cardiovascular and cerebrovascular diseases are the top killer of the elderly.In recent years,there is a trend of low age in our country.At present,minimally invasive vascular interventional surgery is the most effective treatment for this disease with minimal sequelae,but this technology has high requirements for vascular interventional surgeons,and training a qualified vascular interventional surgeon costs a lot and the period is long.The traditional training methods mainly consist of donating cadavers,mannequins,experimental animals and patients,but these methods have some drawbacks.Therefore,in recent years,relevant researchers have gradually turned their attention to the increasingly mature virtual reality technology,hoping to achieve a breakthrough in the training of vascular interventional surgery doctors with the help of virtual reality technology.In this paper,the training system of vascular interventional surgery doctors is studied based on virtual reality technology.The vascular deformation in virtual interventional surgery and the physical reality simulation of guide wire were studied,and at last,the catheter guide wire and vascular deformation were tested and evaluated.First of all,in view of the existing training system for vascular interventional surgery doctors based on virtual reality technology at the present stage,the blood vessels cannot deform during the training process,this paper conducts physical modeling of the virtual blood vessel model based on the point-spring model.First,corresponding elastic modulus parameters are selected according to the physical characteristics of the soft tissues of the blood vessels.It was converted into the elastic coefficient in the particle-spring model through the formula.Finally,physical modeling of blood vessels was carried out through the particle-spring model,and a blood vessel model with deformation effect was obtained in Unity 3D platform.Then,in view of the shortcomings of the visual simulation effect of the guide wire model in the training system of vascular interventional surgery based on virtual reality technology at the present stage of the laboratory,cosserat elastic rod theory based on position dynamics was used to conduct the real modeling of the guide wire.According to the physical characteristics of the guide wire,the distance constraint,bending constraint and other constraint methods are introduced to the guide wire model to enhance the physical simulation effect of the guide wire.Moreover,due to the low fidelity of the model of the algorithm based on position dynamics,the virtual guide wire model is built by adding cosserat elastic rod theory,and the constraint method in the original algorithm based on position dynamics is modified to increase the authenticity of the simulation of guide wire motion in the virtual environment.Finally,this paper conducted experiments and evaluations on the vascular deformation effect in the virtual environment of the whole system and the physical simulation effect of the guide wire.The experimental results showed that when the blood vessels were subjected to the collision force in the virtual environment,the blood vessels would produce different deformation effects according to the magnitude of the collision force,and the researchers could get a good visual feedback effect during training.In the physical simulation of the guide wire,it is found that the motion state of the guide wire with cosserat elastic rod model added is better than that of the guide wire modeling based on the position dynamics algorithm.In addition,the cosserat physical modeling method based on position dynamics has a good authenticity in the simulation of guide wire modeled.In addition,we also added the variable of the stiffness value for the guide wire.For different guide wire,the operator can modify the stiffness value to change the stiffness of the guide wire,which adds greater flexibility for the use of the virtual doctor training system.