介入导管主从操作装置的力觉再现研究

发布时间：2018-03-22 11:07

本文选题：主从操作装置　切入点：三维重建　出处：《郑州大学》2017年硕士论文　论文类型：学位论文

【摘要】：目前在治疗心血管疾病的微创介入手术中,常结合手术辅助机器人系统来完成操作,以提高手术精度并降低医生的工作强度。然而,目前多数手术辅助系统不具备介入导管的力觉信息反馈功能,即没有实现医生在手术外间通过主从操作技术来真正体验到手术的临场感。因此,设计具有力觉再现功能的导管操作系统成为该领域的主要研究方向。本课题针对主从操作机器人系统进行了研究,提出了主从操作装置的力觉再现方案,并建立了由运动控制、主动控制及实际操作三个模块组成的力觉再现系统。运动控制模块是利用编码器的脉冲信号实现从手操作机构的导管介入运动。主动控制模块是在模拟导管受力的基础上,建立导管模拟力与主手阻尼力的匹配及控制方法;实际操作模块是在建立的主手阻尼力与系统控制电流之间的函数关系的基础上,通过力传感器实时检测导管前端受力,以实现主手阻尼力的实时调整并为后续实验积累数据。构建精确的胸主动脉三维模型是实现分析导管受力情况的前提,本研究在类比多种医学图像处理算法后,采用了基于均值漂移和层次聚类的图像分割算法(MSHC),实现了对胸主动脉彩色切片图像的分割处理并完成了血管模型重建;利用ANSYS CFX有限元分析软件对模型进行了瞬态血流模拟,获得了所要研究的不同位置处血流速度,并得出导管在血管中无壁碰情况下的受力与其介入长度之间的函数方程;另外对不同壁碰角度进行了分析,分析结果为后续主手操作机构的设计提供了参数依据。主手操作机构为医生提供阻尼力,可实现机构中磁流变液阻尼力随外加磁场变化而发生变化。基于此,建立了导管不同状态下受力与主手阻尼力间的关系,完成了对主手操作机构的几何参数设计,同时对其磁路进行了数值计算并得到系统控制电流与主手阻尼力之间的函数关系。本研究完成了主从操作装置实验平台的搭建并进行了相关实验。结果表明,主手阻尼力的输出效果与所设计的控制系统相符,较好地实现了力觉再现功能。
[Abstract]:At present, in the minimally invasive interventional surgery for cardiovascular diseases, the surgical assisted robot system is often used to complete the operation in order to improve the accuracy of the operation and reduce the work intensity of the doctor. However, At present, most surgical assistance systems do not have the force information feedback function of interventional catheters, that is, they do not realize that doctors can truly experience the operation's presence by master-slave operation technology outside the operation. It is the main research direction in this field to design a conduit operating system with force sense reproducing function. In this paper, the master-slave robot system is studied, and the force reproduction scheme of master-slave operation device is put forward, and the motion control is established. The motion control module uses the pulse signal of the encoder to realize the catheter intervention movement of the slave operation mechanism. The active control module is based on simulating the force of the conduit. The matching and control method between the simulated duct force and the main hand damping force is established, and the actual operation module is based on the functional relationship between the main hand damping force and the control current of the system, the force on the front end of the conduit is measured by force sensor in real time. In order to realize the real-time adjustment of the damping force of the master hand and accumulate data for the subsequent experiments, it is the premise to construct a precise three-dimensional model of thoracic aorta to analyze the stress of the catheter. The image segmentation algorithm based on mean shift and hierarchical clustering is used to segment the color slice image of thoracic aorta and to reconstruct the vascular model, and the transient blood flow is simulated by ANSYS CFX finite element analysis software. The blood flow velocities at different locations are obtained, and the functional equations between the force on the catheter and its interventional length under the condition of no wall impact in the vessel are obtained, and the different wall impact angles are also analyzed. The results provide a parameter basis for the subsequent design of the main hand operation mechanism. The main hand operation mechanism provides the doctor with damping force, which can realize the change of the magnetorheological fluid damping force in the mechanism with the change of the external magnetic field. The relationship between the force and the damping force of the main hand is established, and the geometric parameters of the main hand operating mechanism are designed. At the same time, the magnetic circuit is numerically calculated and the functional relationship between the control current and the damping force of the main hand is obtained. In this study, the experimental platform of the master-slave operating device is built and the related experiments are carried out. The results show that, The output effect of the main hand damping force is consistent with the designed control system.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R318;TP242

【相似文献】