·高被引论文摘要·

被引频次：473

国内外虚拟现实技术的研究现状

姜学智，李忠华



·高被引论文摘要·

被引频次：473

国内外虚拟现实技术的研究现状

姜学智，李忠华

摘要：虚拟现实技术是由计算机产生，通过视、听、触觉等作用，使用户产生身临其境感觉的交互式视景仿真，具有多感知性、存在感、交互性和自主性等特征，文章介绍了动态环境建模技术，实时三维图形生成技术，立体显示和传感器技术，应用系统开发工具，系统集成技术。目前已在军事、医学、设计和娱乐等领域得到了广泛应用。美日等发达国家对其进行了广泛的研究，取得了重大成果。国内的研究也取得了一定的成果。 虚拟现实技术是现代仿真技术的一个重要发展方向，是一种多源信息熔合的交互式的三维动态视景和实体行为的系统仿真。文章从中国古代的模拟飞行动物的有声风筝到现代美国飞行模拟器的发明；从虚拟现实的“Artificial Reality”到“Virtual Reality”、三个关键元素到三个基本特征的提出，文章首次从新的视角阐述虚拟现实技术的演变发展史及其理论形成，概括了VR发展的特点。首次提出用通式来表达VR的属性。进一步地简单介绍了VR技术在军事、工程、医学、文化教育等方面取得的成果和应用。最后展望了虚拟现实技术的发展前景，未来研究的热点。 虚拟现实是人类在探索自然过程中创造形成的一种用于认识自然、模拟自然，进而更好地适应和利用自然的科学方法和技术。文中在分析虚拟现实全过程的基础上，给出虚拟现实问题的不同分类及一种理论表达，并抽象出虚拟现实领域的三大科学技术问题类；在此基础上从虚拟现实中的建模方法、虚拟现实表现技术、人机交互及设备、虚拟现实开发平台与支撑环境和虚拟现实应用等几个方面论述了虚拟现实当前的主要研究目标、研究成果和发展趋势；最后指出虚拟现实需要进一步致力研究解决的若干理论和技术问题。 虚拟现实技术是多功能的交互技术，该文介绍了虚拟现实技术及其发展过程、概念特征、研究内容以及应用的主要领域，并且结合虚拟现实技术的应用展望了虚拟现实技术的发展前景。 虚拟现实技术的特征可用3个I，即Immersion（沉浸感，也称浸入感、临场感）、Interaction（交互性）、Imagination（想象力）来描述。其中，沉浸感能使用户感受到真切地进入到虚拟空间之中，用户将感觉不到身体所处的外部环境，而“融合”到虚拟世界中去；交互性则能使用户实时地控制虚拟空间中虚拟物体的行为，从而使用户感觉到自己是虚拟空间的主体，用户还可通过三维交互设备直接控制虚拟世界中的对象；而想象力则是人对虚拟空间的创造能力。 建模技术是虚拟现实中的关键技术之一，经历了从几何建模、物理建模到行为建模的发展进程，行为建模方法真正体现了虚拟现实的特征。目前，以行为建模方法为代表的新一代建模方法的研究方兴未艾，其应用前景非常可观。 分析了虚拟现实（VR）技术区别于相邻近的技术的重要特征，回顾了虚拟现实技术发展的三个阶段。介绍了虚拟现实技术在美国等国家的研究现状、主要技术及关键技术的开发状况。 虚拟现实是一种高度逼真的模拟人在自然环境中视、听、动等行为的人机界面。图形生成是虚拟现实技术的重要瓶颈。本文对面向虚拟现实的实时图形生成技术及其发展情况作了详细的介绍和综述。其主要内容是图形生成的硬件体系结构以及在虚拟现实的真实感图形生成中用于加速的各种有效技术。 虚拟现实技术是一门新兴边缘的技术，研究内容涉及多个领域，应用十分广泛，被公认为是21世纪重要的发展学科以及影响人们生活的重要技术之一。从虚拟现实的概念出发，对虚拟现实技术的国内外研究现状进行了充分论述，并展望了虚拟现实的发展趋势。 “虚拟现实”就是一种可以创建和体验虚拟世界的计算机系统。这种系统生成的各种虚拟环境，作用于用户的视觉、听觉、触觉，使用户产生身临其境的感觉，沉浸其中。而所谓虚拟世界则是虚拟环境或给定仿真对象的集合虚拟现实是近年发展起来的一项新技术，目前已广泛地应用于许多领域。该文阐述了虚拟现实技术的产生、概念、特征及其意义、虚拟现实技术的技术组成和艺术、情感魅力，分析了虚拟现实技术的研究内容、方向和技术瓶颈。

关键词：虚拟现实技术；虚拟环境；研究现状 虚拟现实；关键元素；3I特征；通式；演变发展 虚拟现实；建模；绘制；人机交互；开发平台 虚拟现实技术；分布式虚拟环境；交互技术；心理学 虚拟现实；虚拟环境；混合建模；几何实体；光源照射；世界坐标系；用户坐标系；虚拟物体；图象合成；虚拟对象 虚拟现实；几何建模；物理建模；行为建模 虚拟现实技术；发展过程；研究现状 虚拟现实；图形生成；图形加速 虚拟现实；研究现况；发展趋势 虚拟现实；交互技术；虚拟环境；沉浸；构想

虚拟现实技术的演变发展与展望

邹湘军，孙健，何汉武，等

来源出版物：系统仿真学报, 2004, 16 (9): 1905-32-1909

被引频次：284

虚拟现实综述

赵沁平

来源出版物：中国科学（F辑：信息科学）, 2009, 39(1): 2-46

被引频次：233

展望虚拟现实技术

苏建明，张续红，胡庆夕

来源出版物：计算机仿真, 2004, 21(1): 18-21

被引频次：179

虚拟现实中基于图形与图象的混合建模技术

李自力

来源出版物：中国图象图形学报：A 辑, 2001, 6(1): 96-101

被引频次：177

虚拟现实中的建模方法

杨克俭，刘舒燕，陈定方

来源出版物：武汉理工大学学报, 2001, 23(6): 47-50

被引频次：168

虚拟现实技术的发展过程及研究现状

吴迪，黄文骞

来源出版物：海洋测绘, 2002, 22(6): 15-17

被引频次：151

虚拟现实的图形生成技术

刘学慧，吴恩华

来源出版物：中国图象图形学报：A 辑, 1997, 2(4): 205-212

被引频次：150

虚拟现实技术的国内外研究现状与发展

许微

来源出版物：现代商贸工业, 2009, 21(2): 279-280

被引频次：149

虚拟现实技术概述

张占龙，罗辞勇，何为

来源出版物：计算机仿真, 2005, 22(3): 1-3

被引频次：1097

来源出版物：IEEE Transactions on Neural Systems and Rehabilitation Engineering, 2001, 9(3): 308-318

被引频次：228

Virtualized reality: Constructing virtual worlds from real scenes

Kanade, T; Rander, P; Narayanan, PJ; et al.

来源出版物：IEEE Multimedia, 1997 (1): 34-47

被引频次：221

Virtual reality surgical simulator

Satava, RM

来源出版物：Surgical Endoscopy, 1993, 7(3): 203-205

被引频次：217

Proficiency-based virtual reality training significantly reduces the error rate for residents during their first 10 laparoscopic cholecystectomies

Ahlberg, G; Enochsson, L; Gallagher, AG; et al.

来源出版物：The American Journal of Surgery, 2007, 193(6): 797-804

被引频次：181

Virtual reality exposure therapy for Vietnam veterans with posttraumatic stress disorder

Rothbaum, BO; Hodges, LF; Ready, D; et al.

来源出版物：The Journal of Clinical Psychiatry, 2001, 62(8): 1, 478-622

被引频次：181

Virtual bronchoscopy - Relationships of virtual reality endobronchial simulations to actual bronchoscopic findings

Vining, DJ; Liu, K; Choplin, RH; et al.

来源出版物：CHEST Journal, 1996, 109(2): 549-553

来源出版物：辽宁工程技术大学学报: 自然科学版, 2004, 23(2): 238-240

被引频次：307

来源出版物：Nature Materials, 2003, 2(5): 301-306

被引频次：1059

Self-cleaning surfaces - Virtual realities

Blossey, R

Abstract:In the 19th century, Oscar Wilde stated “We live, I regret to say, in an age of surfaces”. Today, we do so even more, and we do not regret it: key advances in the understanding and fabrication of surfaces with controlled wetting properties are about to make the dream of a contaminationfree (or ‘no-clean’) surface come true. Two routes to self-cleaning are emerging, which work by the removal of dirt by either film or droplet flow. Although a detailed understanding of the mechanisms underlying the behaviour of liquids on such surfaces is still a basic research topic, the first commercial products in the household-commodity sector and for applications in biotechnology are coming within reach of the marketplace. This progress report describes the current status of understanding of the underlying mechanisms, the concepts for making such surfaces, and some of their first applications. Objective: To demonstrate that virtual realitybook=27,ebook=31(VR) training transfers technical skills to the operating room (OR) environment.Summary Background Data: The use of VR surgical simulation to train skills and reduce error risk in the OR has never been demonstrated in a prospective, randomized, blinded study. Methods: Sixteen surgical residents (PGY 1–4) had baseline psychomotor abilities assessed, then were randomized to either VR training (MIST VR simulator diathermy task) until expert criterion levels established by experienced laparoscopists were achieved (n=8), or control non-VR-trained (n=8). All subjects performed laparoscopic cholecystectomy with an attending surgeon blinded to training status. Videotapes of gallbladder dissection were reviewed independently by two investigators blinded to subject identity and training, and scored for eight predefined errors for each procedure minute (interrater reliability of error assessment r>0.80). Results: No differences in baseline assessments were found between groups. Gallbladder dissection was 29% faster for VR-trained residents. Non-VR-trained residents were nine times more likely to transiently fail to make progress (P<0.007, Mann-Whitney test) and five times more likely to injure the gallbladder or burn nontarget tissue (chi-square=4.27, P<0.04). Mean errors were six times less likely to occur in the VR-trained group (1.19 vs. 7.38 errors per case; P<0.008, Mann-Whitney test). Conclusions: The use of VR surgical simulation to reach specific target criteria significantly improved the OR performance of residents during laparoscopic cholecystectomy. This validation of transfer of training skills from VR to OR sets the stage for more sophisticated uses of VR in assessment, training, error reduction, and certification of surgeons. BACKGROUND: This study examined the impact of virtual reality (VR) surgical simulation on improvement of psychomotor skills relevant to the performance of laparoscopic cholecystectomy. METHODS: Sixteen surgical trainees performed a laparoscopic cholecystectomy on patients in the operating room (OR). The participants were then randomized to receive VR training (ten repetitions of all six tasks on the Minimally Invasive Surgical Trainer-Virtual Reality (MIST-VR)) or no training. Subsequently, all subjects performed a further laparoscopic cholecystectomy in the OR. Both operative procedures were recorded on videotape, and assessed by two independent and blinded observers using predefined objective criteria. Time to complete the procedure, error score and economy of movement score were assessed during the laparoscopic procedure in the OR. RESULTS: No differences in baseline variables were found between the two groups. Surgeons who received VR training performed laparoscopic cholecystectomy significantly faster than the control group (P=0.021). Furthermore, those who had VR training showed significantly greater improvement in error (P=0.003) and economy of movement (P=0.003) scores. CONCLUSION: Surgeons who received VR simulator training showed significantly greater improvement in performance in the OR than those in the control group. VR surgical simulation is therefore a valid tool for training of laparoscopic psychomotor skills and could be incorporated into surgical training programmes. Summary Background Data: To inform surgeons about the practical issues to be considered for successful integration of virtual reality simulation into a surgical training program. The learning and practice of minimally invasive surgery (MIS) makes unique demands on surgical training programs. A decade ago Satava proposed virtual reality (VR) surgical simulation as a solution for this problem. Only recently have robust scientific studies supported that vision. Methods: A review of the surgical education, human-factor, and psychology literature to identify important factors which will impinge on the successful integration of VR training into a surgical training program. Results: VR is more likely to be successful if it is systematically integrated into a well-thought-out education and training program which objectively assesses technical skills improvement proximate to the learning experience. Validated performance metrics should be relevant to the surgical task being trained but in general will require trainees to reach an objectively determined proficiency criterion, based on tightly defined metrics and perform at this level consistently. VR training is more likely to bebook=28,ebook=32successful if the training schedule takes place on an interval basis rather than massed into a short period of extensive practice. High-fidelity VR simulations will confer the greatest skills transfer to the in vivo surgical situation, but less expensive VR trainers will also lead to considerably improved skills generalizations. Conclusions: VR for improved performance of MIS is now a reality. However, VR is only a training tool that must be thoughtfully introduced into a surgical training curriculum for it to successfully improve surgical technical skills. A personal computer (PC)-based desktop virtual reality (VR) system was developed for rehabilitating hand function in stroke patients. The system uses two input devices, a Cyber-Glove and a Rutgers Master U-ND (RMII) force feedback glove, allowing user interaction with a virtual environment. This consists of four rehabilitation routines, each designed to exercise one specific parameter of hand movement: range, speed, fractionation or strength. The use of performance-based target levels is designed to increase patient motivation and individualize exercise difficulty to a patient’s current state. Pilot clinical trials have been performed using the above system combined with noncomputer tasks, such as pegboard insertion or tracing of two-dimensional (2-D) patterns. Three chronic stroke patients used this rehabilitation protocol daily for two weeks. Objective measurements showed that each patient showed improvement on most of the hand parameters over the course of the training. Subjective evaluation by the patients was also positive. This technical report focuses on this newly developed technology for VR rehabilitation. A new visual medium, Virtualized Reality, immerses viewers in a virtual reconstruction of real-world events. The Virtualized Reality world model consists of real images and depth information computed from these images. Stereoscopic reconstructions provide a sense of complete immersion, and users can select their own viewpoints at view time, independent of the actual camera positions used to capture the event. The virtual-reality surgical simulator signals the beginning of an era of computer simulation for surgery. The surgical resident of the future will learn new perspectives on surgical anatomy and repeatedly practice surgical procedures until they are perfect before performing surgery on patients. Primitive though these initial steps are, they represent the foundation for an educational base that will be as important to surgery as the flight simulator is to aviation. It is anticipated that the full development of the surgical simulator will take less than the 40 years which was required for flight simulators to become an indispensable ingredient of pilot training. As the system evolves, many new and yet-to-be-imagined applications will arise, but we must have understanding and patience as we wait for computer power to improve to a point where VR surgical simulation can emerge from its PacMan era. Background: Virtual reality (VR) training has been shown previously to improve intraoperative performance during part of a laparoscopic cholecystectomy. The aim of this study was to assess the effect of proficiency-based VR training on the outcome of the first 10 entire cholecystectomies performed by novices.Methods: Thirteen laparoscopically inexperienced residents were randomized to either (1) VR training until a predefined expert level of performance was reached, or (2) the control group. Videotapes of each resident’s first 10 procedures were reviewed independently in a blinded fashion and scored for predefined errors. Results: The VR-trained groupbook=29,ebook=33consistently made significantly fewer errors (P=0.0037). On the other hand, residents in the control group made, on average, 3 times as many errors and used 58% longer surgical time. Conclusions: The results of this study show that training on the VR simulator to a level of proficiency significantly improves intraoperative performance during a resident’s first 10 laparoscopic cholecystectomies. Background: Virtual reality (VR) integrates real-time computer graphics, body-tracking devices, visual displays, and other sensory input devices to immerse a participant in a computer-generated virtual environment that changes in a natural way with head and body motion. VR exposure (VRE) is proposed as an alternative to typical imaginal exposure treatment for Vietnam combat veterans with posttraumatic stress disorder (PTSD). Method: This report presents the results of an open clinical trial using VRE to treat Vietnam combat veterans who have DSM-IV PTSD. In 8 to 16 sessions. 10 male patients were exposed to 2 virtual environments: A virtual Huey helicopter flying over a virtual Vietnam and a clearing surrounded by jungle. Results: Clinician-rated PTSD symptoms as measured by the Clinician Administered PTSD Scale, the primary outcome measure, at 6-month follow-up indicated an overall statistically significant reduction from baseline (P=0.0021) in symptoms associated with specific reported traumatic experiences. All 8 participants interviewed at the 6-month follow-up reported reductions in PTSD symptoms ranging from 15% to 67%. Significant decreases were seen in all 3 symptom clusters (P<0.02). Patient self-reported intrusion symptoms as measured by the Impact of Event Scale were significantly lower (P<0.05) at 3 months than at baseline but not at 6 months. although there was a clear trend toward fewer intrusive thoughts and somewhat less avoidance. Conclusion: Virtual reality exposure therapy holds promise for treating PTSD in Vietnam veterans. Advances in computer technology have permitted development of virtual reality images of the tracheobronchial tree using data sets derived from helical CT of the chest. To determine the relevance of these images to actual bronchoscopic findings, we compared “virtual bronchoscopy”images with videotaped bronchoscopy results in 20 patients who had undergone both helical chest CT and fiberoptic bronchoscopy during clinical evaluation of their thoracic problems. Suboptimal endobronchial simulations in ten patients identified important, readily-addressed technical requirements for this imaging procedure. In the ten patients with technically suitable renderings of the airway, virtual bronchoscopy simulations accurately demonstrated endobronchial obstructions by tumor in five, airway distortion and/or ectasia in four, and accessory bronchi in another. These preliminary observations suggest that virtual bronchoscopy simulations accurately represent major endobronchial anatomic findings. This technique may have a role in prebronchoscopy planning, endoscopy training, and/or endobronchial therapy, and merits further study.

Virtual reality training improves operating room performance - Results of a randomized, double-blinded study

Seymour, NE; Gallagher, AG; Roman, SA; et al.

来源出版物：Annals of Surgery, 2002, 236(4): 458-464

被引频次：539

Randomized clinical trial of virtual reality simulation for laparoscopic skills training

Grantcharov, TP; Kristiansen, VB; Bendix, J; et al.

来源出版物：British Journal of Surgery, 2004, 91(2): 146-150

被引频次：335

Virtual reality simulation for the operating room -Proficiency-based training as a paradigm shift in surgical skills training

Gallagher, AG; Ritter, EM; Champion, H; et al.

来源出版物：Annals of Surgery, 2005, 241(2): 364-372

被引频次：230

Virtual reality-enhanced stroke rehabilitation

Jack, D; Boian, R; Merians, AS; et al.

Keywords:Cyber Glove; haptic glove; rehabilitation; Rutgers Master II-ND; stroke; virtual reality (VR) computer-assisted diagnosis; computer simulation; bronchoscopy; lung neoplasms; tomography, x-ray computed