Research Of Key Technology In Hip Virtual Surgery Training System And Its Program Realization

The hip is vulnerable to invasion which has complex structure and anatomy location is deep.It requires rich experience for doctors,who want to make accurate surgical plans,and this is exactly what the young doctor lacks,according to the study of 2D tomographic images.Virtual surgery system can provide the virtual scene for the operation of the young doctors as well as they can get the operation experience more quickly and reduces the cost of time and fund compared to the traditional practice of physical exercise.This kind of system is a virtual reality application system that allows doctors to operate in a virtual human body and reproduce the various situations that may be encountered during the operation.The core modules of the hip surgery training system are soft tissue deformation module,collision detection module,cutting module and visualization module.The muscle deformation module,collision detection module and cutting module was completed in this study.Self-selection algorithm for embedded operating area was proposed in muscle deformation module of this study.This algorithm makes the scale of the tetrahedral element which is involved in calculation greatly reduced,and the speed of calculation is greatly improved without significant influence on the accuracy by the way of the operating area is chosen independently for finite element calculation.At the same time,in order to avoid the time consumption of the self-selection algorithm in the operation area to search adjacent tetrahedron affects the overall calculation speed.To solve the above problems,all tetrahedral elements are topological reconstruction.Compared with the muscle deformation module without the use of the algorithm,the acceleration algorithm of this paper improves the speed of deformation calculation by 30 times,but the accuracy is the original 70%.Latitude and longitude collision detection algorithm was proposed in this study of collision detection module,the detection process can be accelerated by the search algorithm.First,the 3D information of triangular patch was transformed to latitude and longitude information.Then,the latitude and longitude data structure of independent design was used to complete collision detection and corresponding update operation.The detection and update operation of this algorithm more efficient contrast with traditional bounding box collision detection algorithm.By testing,the algorithm can meet the needs of collision detection module.Cutting algorithm for transient display delay processing was proposed in this paper of cutting module.To ensure the subsequent finite element calculation efficiency can be kept stable and efficient,a path separation scheme is proposed and does not use the tetrahedral element subdivision scheme.The transient display delay processing of the cutting algorithm proposed in this study avoids the impact of topological structure adjustment of cutting algorithm on the display fluency.By testing,the cutting display frequency is very stable of the proposed algorithm and meets the requirements of the cutting module of the hip surgery system.