颅颌面种植外科计算机辅助规划系统的设计

为满足颅颌面种植外科手术术前诊断和规划的需要,开发了一种基于CT图像的颅颌面种植外科计算机辅助规划系统,提出了其系统框架结构,阐述了设计中使用的螺旋CT技术数字图像算法,并根据各种功能需求,逐一进行设计和实现.实验和临床应用证明,该系统可以很好地应用于颅颌面外科种植手术规划,大大提高颅面外科手术规划的准确度.     

颅颌面外科辅助手术机器人系统

本文针对颅颌面外科手术中存在的精确定位难以保障、无导航系统、医生长时间手术易疲劳等问题,介绍研制的颅颌面外科辅助手术机器人系统。首先介绍整个系统的组成,然后从颅颌面外科术前手术设计、机器人机械构型、控制系统和导航系统等方面进行详细论述。最后,探讨了颅颌面外科手术机器人的发展方向及下一步的工作。     

基于力反馈的虚拟脊柱手术模拟系统的构建

针对医学手术排练演习和手术教学开发了虚拟脊柱手术模拟平台。在该平台上能够根据手术的真实环境,模拟常用手术器械和脊柱结构,实现人机实时交互。详细介绍了系统的硬件环境参数,并基于3DS MAX的建模和力触觉渲染引擎CHAI 3D进行仿真。仿真实验结果表明,基于力反馈的虚拟脊柱手术模拟系统可以有效地模拟脊柱手术时的力反馈状态,帮助医师进行脊柱手术术前训练,并适用于高校的医学教学和医疗机构人员的培训。     

基于协作空间与灵巧度的机器人辅助微创手术术前规划算法

机器人辅助微创外科手术的术前准备工作相对于传统微创手术更加复杂和关键.为了提高手术执行效率,充分利用机器人特性,本文以机械臂的运动学性能和器械间的协作能力作为优化目标,相应地提出了机械臂灵巧度指标IICV与体内协作空间指标IICS,设计了一套基于NSGA-II的多目标术前规划方法,将微创手术介入位置选择与机械臂初始位姿优化两类术前规划问题作为统一整体优化.最后,将由术前规划算法优化得到的系统性能指标与医生凭借经验给出的结果进行比较.实验结果表明,由优化算法得到的术前规划方案优势明显,能够为机器人辅助微创手术操作提供一个相对理想的手术执行环境.     

基于杆-质点模型实现的脑膜瘤术前训练系统

脑膜瘤是中枢神经系统最为常见的原发性肿瘤,手术摘除是该疾病的首选治疗方案。脑神经外科疾病发病紧急、专家少、会诊难度大,且病灶易与周围组织粘连,手术操作空间狭小。因此,设计术前培训系统帮助医生模拟手术过程是非常必要的,而如何实时模拟手术过程中手术器具与脑膜瘤及周边正常脑组织的交互力是亟待解决的问题。采用改进的杆-质点模型建立脑膜瘤摘除过程中手术器具与病灶的交互过程模型,实时计算交互力,并通过手控器反馈给医生,使医生能够真实感受手术过程。基于C#、Unity 3D 等软硬件系统构建虚拟手术系统平台进行实验,验证了所提出的方法具有实时性,可以满足神经外科手术需求。     

电动力液压驱动四足双臂机器人的设计与实现

针对定基座机器人在复杂环境下作业能力不足的问题,研制出电动力液压四足双臂机器人,将浮动基座与双臂系统的优势有机结合,能够代替人员完成复杂环境下应急处置、工程作业等任务。详细阐述了四足双臂机器人的机械结构、机载电液动力系统、分布式控制系统以及仿真与操作训练平台的设计与实现。提出基于全身虚拟模型的足底力分配方法与足臂协调运动规划方法,实现了躯干浮动基座与双臂系统的联动,大大提升了机器人的作业能力和效率。通过搭建的仿真与操作训练平台完成单臂作业以及双臂协同作业的仿真,验证了所提出控制方法的有效性,并对机器人操作员进行操作训练。在实际样机实验中,测试了单臂抓取以及双臂协同抓取的能力,证明了四足双臂机器人能够满足复杂环境下移动作业的需求。     

基于深度Q网络的人群疏散机器人运动规划算法

针对公共场合密集人群在紧急情况下疏散的危险性和效果不理想的问题，提出一种基于深度Q网络（DQN）的人群疏散机器人的运动规划算法。首先通过在原始的社会力模型中加入人机作用力构建出人机社会力模型，从而利用机器人对行人的作用力来影响人群的运动状态；然后基于DQN设计机器人运动规划算法，将原始行人运动状态的图像输入该网络并输出机器人的运动行为，在这个过程中将设计的奖励函数反馈给网络使机器人能够在"环境-行为-奖励"的闭环过程中自主学习；最后经过多次迭代，机器人能够学习在不同初始位置下的最优运动策略，最大限度地提高总疏散人数。在构建的仿真环境里对算法进行训练和评估。实验结果表明，与无机器人的人群疏散算法相比，基于DQN的人群疏散机器人运动规划算法使机器人在三种不同初始位置下将人群疏散效率分别增加了16.41%、10.69%和21.76%，说明该算法能够明显提高单位时间内人群疏散的数量，具有灵活性和有效性。     

机器人技术在中医正骨手术中的应用研究

本文介绍了一套自行开发的机器人辅助正骨医疗手术平台系统．系统由计算机辅助 手术规划软件和正骨机器人两大部分组成，其中计算机辅助手术规划软件可以采集患者骨折 处的X光图像，机器人则在医生的控制下完成拉伸牵引、旋转、模拟手法复位等动作，使患 者骨折处闭合复位．本系统能够代替医生在X光辐射环境下进行正骨手术，避免射线对医生 身体的损伤，同时提高了手术效率、手术精度和安全性．系统已成功地应用于临床．     

脊柱手术机器人

针对脊柱手术中的椎弓根钉内固定术,为克服医生操作手术时定位精度难以保证、长时间手术易疲劳等问题,设计了一套脊柱手术机器人系统用于辅助实施椎弓根钉内固定术。机器人为5自由度,充分考虑手术机器人对安全性和工作空间有效覆盖的要求,进行了构型设计,并完成了相应的机器人运动学分析。控制系统是由图像导航下的主动控制和基于力传感器的被动拖拽控制两个模式进行控制。主动控制下,医生通过导航系统提供最优钉道的精确位置信息,机器人根据医生的规划路径自主到达手术点;被动力拖拽控制基于导纳控制原理对医生作用在机器人末端执行器的操作力进行映射,并以此形成跟随拖动动作的机器人运动控制指令。针对力拖拽控制的实验验证了机器人在被动拖拽控制模式下能够柔顺地跟踪医生的操作动作。     

在线协同包装设计虚仿教学平台设计与开发

为了增强学生使用协同设计和虚拟仿真训练教学工具的综合能力,本文提出了一个在线协同包装设计虚仿教学平台的建设方案。该方案对教学平台的整体规划、协同设计、资源库、生产原理与仿真等平台模块提出了具体的建设措施,并应用于包装设计课堂的实际教学。实践的结果表明,本文方案建设的教学平台能够满足师生对于在线协同设计和虚拟仿真训练的学习需求。     

Advanced virtual endoscopic pituitary surgery

Endoscopy has recently been introduced to endonasal transsphenoidal pituitary surgery as a minimally invasive procedure for the removal of various kinds of pituitary tumors. To reduce morbidity and mortality with this new technique, the surgeon must be well-trained and well-prepared. Virtual endoscopy can be beneficial as a tool for training, preoperative planning, and intraoperative support. This paper introduces STEPS, a virtual endoscopy system designed to aid surgeons in getting acquainted with the endoscopic view of the anatomy, the handling of instruments, the transsphenoidal approach, and challenges associated with the procedure. STEPS also assists experienced surgeons in planning a real endoscopic intervention by getting familiar with the individual patient anatomy, identifying landmarks, planning the approach, and deciding upon the ideal target position of the actual surgical activity. The application provides interactive visualization, navigation, and perception aids and the possibility of simulating the procedure, including haptic feedback and simulation of surgical instruments.     

Development scheme of haptic-based system for interactive deformable simulation

This paper aims to develop a novel scheme for interactively deformable simulation with haptic feedback. All design modules are packaged and implemented, and the experiments are conducted to study the effects of interactive deformation. The study compares the experimental results of haptic feedback by different force propagation methods, according to the Hounsfield unit (HU) of volume data. Additionally, the estimation of optimal propagation depth is illustrated by using a mass-spring model. Finally, by using the proposed scheme, a haptic-based medical simulation system for brain surgery is investigated. The integration test results with haptic feedback scenarios show that the proposed development scheme can certainly comply with the design modules, and the deformable simulation and haptic force reach a good agreement.     

面向上颌骨骨折复位手术的虚拟系统设计

基于3D计算机触觉视觉交互(CHAI3D)和开放图形库(Open GL)等开源软件,设计了针对上颌骨复位手术的仿真系统。使用真实病例的CT图像搭建虚拟场景,通过Geomagic力反馈设备对虚拟模型进行三维操作并输出触觉反馈。在原有单点碰撞算法的基础上,提出了使用多个中介代理的多点碰撞算法,避免了虚拟手术工具的手柄插入虚拟器官的不实仿真;通过力反馈设备对头颅骨模型进行选择、移动和旋转,模拟手术中对头颅骨的移动和放置。系统可用于训练医学院学生,也可用于复杂手术的术前规划。     

vKASS: a surgical procedure simulation system for arthroscopic anterior cruciate ligament reconstruction

Arthroscopic surgeries, which are widely used for anterior cruciate ligament (ACL) reconstruction, not only require advanced hand–eye coordination but also involve complicated surgical procedure, necessitating simulation‐based training for surgeons. This paper describes a surgical procedure simulation system for the training of arthroscopic ACL reconstruction. Different from existing simulation‐based training systems for basic surgical skills, this system provides a complete simulation for the entire procedure of arthroscopic ACL reconstruction, involving operations such as puncturing, probing, incision, and drilling. In this system, we employ a linear elastic finite element method and position‐based dynamics for deformable modeling. Simplified vertex duplicating method and an implementation of real‐time Boolean operations are proposed for the topological change of tissue models involved in the incision simulation and tunnel construction. Two specially designed force feedback models are introduced for the haptic rendering of probing and drilling operations. By using these fast and stable simulation methods, this system is able to provide real‐time realistic graphical and haptic feedback to the user, making it efficient and practical for training purpose. Feedback from the surgeon trainees shows that this system is very effective in training not only for basic surgical skills but also for the complex surgical procedure. Copyright © 2012 John Wiley & Sons, Ltd.     

Beyond the visuals: tactile augmentation and sensory enhancement in an arthroscopy simulator

This paper considers tactile augmentation, the addition of a physical object within a virtual environment (VE) to provide haptic feedback. The resulting mixed reality environment is limited in terms of the ease with which changes can be made to the haptic properties of objects within it. Therefore sensory enhancements or illusions that make use of visual cues to alter the perceived hardness of a physical object allowing variation in haptic properties are considered. Experimental work demonstrates that a single physical surface can be made to ‘feel’ both softer and harder than it is in reality by the accompanying visual information presented. The strong impact visual cues have on the overall perception of object hardness, indicates haptic accuracy may not be essential for a realistic virtual experience. The experimental results are related specifically to the development of a VE for surgical training; however, the conclusions drawn are broadly applicable to the simulation of touch and the understanding of haptic perception within VEs.     

Computer-based virtual reality simulator for phacoemulsification cataract surgery training

Recent research in virtual reality indicates that computer-based simulators are an effective technology to use for surgeons learning to improve their surgical skills in a controlled environment. This article presents the development of a virtual reality simulator for phacoemulsification cataract surgery training, which is the most common surgical technique currently being used to remove cataracts from the patient’s eyes. The procedure requires emulsifying the cloudy natural lens of the eye and restoring vision by implanting an artificial lens through a small incision. The four main procedures of cataract surgery, namely corneal incision, capsulorhexis, phacoemulsification, and intraocular lens implantation, are incorporated in the simulator for virtual surgical training by implementing several surgical techniques. The surgical activity that are applied on the anatomy of the human eye, such as incision, grasping, tearing, emulsification, rotation, and implantation, are simulated in the system by using different types of mesh modifications. A virtual reality surgical simulator is developed, and the main procedures of phacoemulsification cataract surgery are successfully simulated in the system. The simulation results of the training system show that the developed simulator is capable of generating a virtual surgical environment with faithful force feedback for medical residents and trainees to conduct their training lessons via the computer using a pair of force-feedback haptic devices. In addition, the successful simulation of the mesh modifications on the human eyeball with visual realism and faithful force feedback throughout the surgical operation shows that the developed simulator is able to serve as a virtual surgical platform for surgeons to train their surgical skills.     

Influences of haptic communication on a shared manual task

With the advent of new haptic feedback devices, researchers are giving serious consideration to the incorporation of haptic communication in collaborative virtual environments. For instance, haptic interactions based tools can be used for medical and related education whereby students can train in minimal invasive surgery using virtual reality before approaching human subjects. To design virtual environments that support haptic communication, a deeper understanding of humans′ haptic interactions is required. In this paper, human′s haptic collaboration is investigated. A collaborative virtual environment was designed to support performing a shared manual task. To evaluate this system, 60 medical students participated to an experimental study. Participants were asked to perform in dyads a needle insertion task after a training period. Results show that compared to conventional training methods, a visual-haptic training improves user′s collaborative performance. In addition, we found that haptic interaction influences the partners′ verbal communication when sharing haptic information. This indicates that the haptic communication training changes the nature of the users′ mental representations. Finally, we found that haptic interactions increased the sense of copresence in the virtual environment: haptic communication facilitates users′ collaboration in a shared manual task within a shared virtual environment. Design implications for including haptic communication in virtual environments are outlined.     

Interactive mixed reality white cane simulation for the training of the blind and the visually impaired

This paper presents a mixed reality tool developed for the training of the visually impaired based on haptic and auditory feedback. The proposed approach focuses on the development of a highly interactive and extensible Haptic Mixed Reality training system that allows visually impaired to navigate into real size Virtual Reality environments. The system is based on the use of the CyberGrasp™ haptic device. An efficient collision detection algorithm based on superquadrics is also integrated into the system so as to allow real time collision detection in complex environments. A set of evaluation tests is designed in order to identify the importance of haptic, auditory and multimodal feedback and to compare the MR cane against the existing Virtual Reality cane simulation system.     

激光模拟训练系统设计

为了提高竞技体育训练的实时监测和动态评估能力,采用激光跟踪模拟训练方法进行竞技体育实时动态分析和训练系统设计,提出一种基于运动行为激光成像动态特征采集的竞技体育实时动态分析模拟系统系统设计方法。首先构建训练系统的总体结构模型,采用激光实时成像扫描仪进行体育训练三维图像采集,结合图像处理算法进行人体形态特征分析和动作矫正。然后进行系统的硬件设计,采用前级放大电路进行激光成像输出信号放大,构建CAN总线驱动电路进行激光模拟训练系统控制器与物理总线之间的接口设计。最后在嵌入式ARM中进行系统嵌入式开发设计,系统调试结果表明,采用该系统进行竞技体育人体实时动态分析,能准确反馈人体运动行为特征信息,结合专家系统进行动作矫正,指导体育训练,提高训练效果。     

A multiprocessor decoupled system for the simulation of temporal bone surgery

A training system for simulating temporal bone surgery is presented. The system is based on patient-specific volumetric object models derived from 3D CT and MR imaging data. Real-time feedback is provided to the trainees via real-time volume rendering and haptic feedback. The performance constraints dictated by the human perceptual system are met by exploiting parallelism via a decoupled simulation approach on a multi-processor PC platform. In this paper, system components are detailed and the current state of the integrated system is presented.