导管介入手术中虚拟现实技术与主从控制研究

发布时间：2018-03-27 23:41

  本文选题：导管介入手术　切入点：虚拟现实　出处：《南京航空航天大学》2015年硕士论文

【摘要】：相对于传统手术,微创介入手术具有治疗快,创伤小,成本低等优点,因此被广泛应用到心血管等疾病的诊断与治疗当中。然而,当前的介入手术操作存在着操作难度高,控制方式单一,反馈信息缺失以及手术训练成本高、效果差等问题,针对这些不足,本文对导管介入手术中的虚拟现实技术和主从控制技术进行了深入的研究和分析。本文设计了一套含力/触觉反馈的主从控制导管介入手术系统,系统由虚拟手术子系统和主从控制子系统组成。虚拟系统中通过加入力/触觉反馈使操作者在进行手术训练以及实际手术中能够具有更好的临场感,主从控制的实现方式使得医生能够从具有强辐射的手术场所解放出来,降低了手术操作的技术门槛。为了实现虚拟系统中力/触觉反馈与形变效果,本文分别从柔性体建模,碰撞检测以及力反馈实现三个方面进行分析。通过分析人体软组织的生物材料特性,本文将软组织器官的物理模型简化为粘弹性模型,在分析和总结了弹簧-质点模型,有限元模型以及边界元模型等常用的物理模型建模方法之后,本文提出了一种基于弹簧-质点模型的骨架球弹簧模型,用于对虚拟软组织器官的物理模型构建;通过总结和对比经典包围盒算法,球包围盒、AABB包围盒、OBB包围盒以及K-DOPs包围盒的各自特征和适用范围,本文设计了一种基于球包围盒且适用于骨架球弹簧物理模型的碰撞检测算法;根据骨架球弹簧模型,建立了虚拟反馈力的计算模型,并推导出了虚拟血管的形变计算公式。在主从控制的实现中,本文针对主动导管的绳驱动单元结构分析了其运动学,分别采用空间点对点的映射模型和增量式映射模型建立了主从映射关系,为了减弱由于不可避免的人手抖动带来的主从控制精度的降低,本文设计了一款基于加权的递推均值数字滤波器对人手抖动进行消除。基于理论分析,本文借助Falcon作为虚拟力反馈的触觉设备以及主从控制的主手,PMAC卡作为运动控制卡,在Visual C++平台上以及Open GL和Chai3D函数库的辅助下,组建了系统样机并进行实验,实验结果说明了虚拟反馈的逼真性以及主从控制的有效性。
[Abstract]:Compared with traditional surgery, minimally invasive interventional surgery has the advantages of fast treatment, less trauma and low cost, so it is widely used in the diagnosis and treatment of cardiovascular diseases. The single control mode, the lack of feedback information, the high cost of operation training, the poor effect and so on. In this paper, the virtual reality technology and master-slave control technology in catheter interventional surgery are deeply studied and analyzed. A master-slave control catheter interventional surgery system with force / tactile feedback is designed in this paper. The system is composed of virtual surgery subsystem and master-slave control subsystem. By adding force / tactile feedback in the virtual system, the operator can have a better sense of presence in the operation training and the actual operation. In order to realize force / tactile feedback and deformation effect in the virtual system, the master-slave control enables doctors to free themselves from the surgery site with strong radiation, and reduces the technical threshold of operation. In order to realize the effect of force / tactile feedback and deformation in the virtual system, the flexible body is modeled in this paper. By analyzing the biomaterial characteristics of human soft tissue, the physical model of soft tissue organ is simplified to viscoelastic model, and the spring-mass model is analyzed and summarized. After the physical modeling methods such as finite element model and boundary element model, this paper presents a framework sphere spring model based on spring-mass model, which is used to construct the physical model of virtual soft tissue organ. By summing up and comparing the classical bounding box algorithm, the bounding box AABB bounding box OBB bounding box and K-DOPs bounding box have their respective characteristics and applicable scope. In this paper, a collision detection algorithm based on sphere bounding box and suitable for the physical model of skeleton sphere spring is designed, and a virtual feedback force calculation model is established according to the skeleton sphere spring model. In the realization of master-slave control, the kinematics of the rope-driven unit structure of the active catheter is analyzed. The spatial point-to-point mapping model and the incremental mapping model are used to establish the master-slave mapping relationship respectively. In order to reduce the master-slave control precision caused by the inevitable manual jitter, the master-slave mapping model is proposed. In this paper, a weighted recursive mean digital filter is designed to eliminate the hand jitter. Based on the theoretical analysis, this paper uses Falcon as a virtual force feedback tactile device and a master-slave control PMAC card as a motion control card. With the help of Visual C platform and Open GL and Chai3D function library, the prototype of the system is constructed and the experiments are carried out. The experimental results show that the virtual feedback is realistic and the master-slave control is effective.
【学位授予单位】：南京航空航天大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TP391.9;R61

【参考文献】

中国期刊全文数据库 前10条

1 郭煜;秦t，

本文编号：1673812