Research On Force Feedback Surgery Platform Based On Virtual Reality Technology

With the development and application of computer technology,modern people's lives are increasingly receiving the influence of informationization.Virtual surgery combined with virtual reality technology has emerged as the times require.Virtual surgery can not only solve the problem of surgery training of new doctors to a large extent,but also can be used for a series of operations that can not be realized by traditional surgery such as preoperative planning,intraoperative guidance,and postoperative recurrence.This article uses liver as a surgical target to establish a virtual surgical platform.First of all,in terms of virtual surgical geometry modeling,surgical instruments are modeled using Solidworks.The liver tissue with irregular shape and structure uses medical modeling software Mimics to perform three-dimensional reconstruction based on liver CT images.Secondly,in the physical modeling of virtual surgery,virtual surgical instruments are used to physically model the skeined balls on the front end of the surgical instruments.For liver tissue,the liver STL files are tetrahedrally segmented using the TetGen algorithm.The skeletal ball is arranged on the vertices of the grid,and an elastic spring and a damper are arranged in parallel between adjacent vertices to establish a mass point spring model and constitute a physical model of the liver.Thirdly,on the software side,the hepatic tissue deformation program and force feedback program were written using the open source C++ library CHAI3 D,and tactile feedback devices were used to interact with the surgical instruments in the virtual environment.A collision detection algorithm was programmed to use AABB enclosures to accurately and quickly locate surgical instruments and liver tissue models.In terms of hardware,using a 3D glasses and a 144 Hz display,the virtual surgical scene is displayed in a stereoscopic manner and can be rotated and moved in a three-dimensional space.Finally,according to the experimental results,the number of vertices in the particle spring model is properly selected to maintain the stability of the visual refresh frequency and the haptic refresh frequency in the simulation,and the conventional operation such as touch in the virtual surgery is completed and the liver model is quickly deformed and the feedback is quickly correct.The feedback force proved the real-time and authenticity of the virtual liver surgery platform.