共查询到20条相似文献，搜索用时 72 毫秒
1.
人体上肢运动链模型的准确构建和仿真设计是进行虚拟人体运动和控制的关键技术,是实现虚拟人体运动控制和模式识别的理论前提。传统方法采用几何法、解析法等模拟人体上肢运动链模型,无法有效实现人体上肢运动链的高自由度控制模拟,产生后期搜索迟钝效应。提出一种基于分层子维空间运动规划的人体上肢运动链六自由度模型构建方法,构建人体上肢运动的各关节单元,得到上肢结构及运动学模型D-H表示方法,设计上肢运动链位姿变换,基于分层子维空间运动规划方案,得到人体上肢运动链动力学模型方程,采用六自由度全关节分析方法分析上肢运动链各关节单元,实验得出该模型构建能更好模拟人体上肢运动链模型,控制误差较传统方法减小,能有效实现人体上肢运动链的高自由度控制模拟。 相似文献
2.
《科技通报》2015,(10)
在对人体运动的分析中,关节旋转是人体运动的关键组成部分,研究肢体关节旋转助力模型提高对运动关节扩展解析能力,提高运动辅助训练水平,传统方法采用基于随机采样运动规划方法,存在对肢体关节的路标点移动路径规划不准确等问题。通过求解运动模式下的肢体全部关节的驱动作用力矩,提出一种运动链位姿变换坐标系下的肢体关节旋转助力模型建立方法。构建一种分层子维空间运动规划概念模型,保持下肢的左右脚和左右腿关节不动,设由腰部和左右手臂构成的运动链位姿变换坐标系,进行运动链位姿变换运动学设计,在运动链位姿变换坐标系下实现对肢体关节旋转助力模型改进设计。仿真结果表明,采用该模型,能有效准确地仿真计算出关节的驱动力矩,对关节力矩控制识别准确率较高,控制精度较高,对肢体受力力矩的计算和跟踪性能较好,有效指导体育训练。 相似文献
3.
<正>本文提出了通过头部运动控制井下摄像头的方法。首先通过Kinect体感设备获取人体头部和肩部图像景深数据,并采用骨骼跟踪技术对其进行处理,建立各个关节的3D坐标;再根据3D坐标值计算出头部的摆动角度,控制系统根据用户需求将其转变为控制信号传送给井下云台控制器,从而实现井下摄像头旋转方向和角度的控制。试验表明,该方法能够有效地控制井下摄像头。 相似文献
4.
智能排爆机器人
“智能排爆机器人”性能先进,取得多项技术创新。它基于多级控制结构,采用人工智能层及运动控制层,运动控制层又由补偿器及反馈控制组成,反馈采用P C-104的嵌入式结构,两层之间的联络由手眼协调担任。在手眼协调过程中,多次利用双目视觉计算出的三维坐标与机器手臂当前的姿态,实时地计算出机器手臂的目标姿态,并控制各关节运动到目标姿态。其主要在双目视觉计算精度和手眼协调系统上做了突破。在双目视觉标定过程中,采用了更接近真实成像过程的畸变模型,并且在参数估计的过程中利用线形求解与非线性估计相结合的方法,更精确和有效地估计出成像模型的参数。经实验,系统的双目视觉计算算法能将误差控制在0.3%之内,利用手眼协调系统,弥补了一次计算以及手臂运动过程中可能造成的误差,将图像处理绝对误差控制在1m m之内,极大地提高了该排爆机器人系统的性能以及实用性。 相似文献
“智能排爆机器人”性能先进,取得多项技术创新。它基于多级控制结构,采用人工智能层及运动控制层,运动控制层又由补偿器及反馈控制组成,反馈采用P C-104的嵌入式结构,两层之间的联络由手眼协调担任。在手眼协调过程中,多次利用双目视觉计算出的三维坐标与机器手臂当前的姿态,实时地计算出机器手臂的目标姿态,并控制各关节运动到目标姿态。其主要在双目视觉计算精度和手眼协调系统上做了突破。在双目视觉标定过程中,采用了更接近真实成像过程的畸变模型,并且在参数估计的过程中利用线形求解与非线性估计相结合的方法,更精确和有效地估计出成像模型的参数。经实验,系统的双目视觉计算算法能将误差控制在0.3%之内,利用手眼协调系统,弥补了一次计算以及手臂运动过程中可能造成的误差,将图像处理绝对误差控制在1m m之内,极大地提高了该排爆机器人系统的性能以及实用性。 相似文献
5.
传统方法构建的人体动力学仿真模型只能求解整体受力和发力参数,对各个关节驱动作用力矩的求解模型未提及。提出一种基于7连杆模型结构的人体下肢动力学分析模型,引入机械系统动力学分析用的ADAMS软件到人体动力学分析中,求解各种运动模式下人体下肢左右腿各关节驱动作用力矩。对人体运动Lagrange动力学方程式进行优化求解,得出详实的理论分析值和仿真数据,并进行对比分析。仿真实验表明,构建的单腿支撑和跑步运动模型下的人体下肢动力学分析模型,能有效准确地仿真计算出人体下肢全部关节的驱动力矩,仿真结果为分析人体最佳发力模式,指导和优化体育训练具有很好的理论参考价值。 相似文献
6.
在人体运动跟踪建模中,需要对样本集的多样性特征进行贫化处理,以提高全关节驱动模式运动状态跟踪的准确性。传统方法采用量子进化和粒子滤波算法进行人体运动跟踪贫化算法实现,算法在全关节多样化样本特征运动模式下,跟踪效果不好。提出一种采用动态分层二值进化处理的改进的量子进化粒子滤波全关节驱动模式跟踪方法,解决多样本特征的贫化问题。进行人体全关节驱动模式动力学分析及人体运动跟踪模型构建,通过动态分层处理技术,获得二值前景图像,求得人体关节的全方位信息特征,通过动态分层二值进化方法,准确地找到各关节位置,构建亮度模型函数,实现贫化处理。实验表明,改进算法能实现对体操运动员运动幅度大的肘、腕、踝部位均得到了准确的跟踪结果,贫化效果较好,运动状态估计精度较高。 相似文献
7.
类脑智能是以计算建模为手段,受脑神经和人类认知行为机制启发,并通过软硬件协同实现的机器智能。类脑器件以及类脑机器人分别作为类脑智能研究的重要内容,其在类脑研究领域受到国内外学者的广泛关注。文章首先分析了类脑器件与计算系统中的类脑芯片和类脑机器人的发展现状和应用前景,重点探讨了类脑芯片在模拟人脑神经元模型和认知计算方面,以及类脑机器人在感知控制和智能生长方面的研究内容。然后,文章介绍了在中科院先导专项支持下,我国在这一方面的初步研究进展以及未来发展方向。最后,针对现有研究中遇到的问题,文章对类脑计算芯片与类脑智能机器人的进一步研究提出了建议,并指出未来研究在仿人运动模型、类人神经运动控制、人机协同的智能机器人控制等方面有望取得重大突破。 相似文献
8.
踝关节是人体下肢的三大关节之一,是人体运动的重要枢纽及承重关节,也是本体感觉与平衡功能的综合反映。同时,躁关节又是体育运动中最易受损伤的关节,其发生率占运动性损伤的10％-30％,尤其是篮球、足球、排球、田径运动员易发此病,是使许多优秀运动员倍受困扰的运动损伤之一,踝关节稳定性与本体感觉系统密切联系,本文综述了国内外近几年踝关节本体感觉的研究进展,为预防踝关节损伤及损伤后踝关节的康复提供理论参考。 相似文献
9.
运动员进行不同的运动项目时,关节所成的角度,运动速度有差异,造成特征捕捉点不能很好对应关键区域,形成特征凌乱对应误差,影响形状基计算的准确性。传统的体育运动图像三维重建算法,受到形状基凌乱的影响,后期建模准确性很难控制。因此提出随机体育运动图像捕捉点虚拟重建中凌乱误差控制算法。利用因式分解法,建立人体运动时的三维动态仿真模型,运用stolt变换将所有图像捕获点的的方位偏移率调整为相同,使其在进行特征匹配时不会产生过大误差,对于过大的凌乱残余误差,进行三阶运动补偿,实现人体运动图像序列中的三维动态仿真建模。实验结果表明,这种算法提高了人体运动图像序列三维动态仿真的真实性。 相似文献
10.
<正>直升机地面共振是一种涉及桨叶摆振运动和旋翼桨毂在旋转平面内运动耦合的动力不稳定现象,是直升机研制中必须加以克服和解决的问题。在进行其他飞行试验前,首先得通过专门的试验和分析计算,切实排除直升机发生地面共振的可能性。直升机地面共振试验一般包括地面共振计算分析所需的部件特性试验和地面共振外场开车试验。地面共振外场开车试验,应在地面共振分析之后,并表明直升机在旋翼全部工作转速范围内,不存在地面工作问题, 相似文献
11.
《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
12.
Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors. 相似文献
13.
《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
14.
A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007. 相似文献
15.
Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction. 相似文献
16.
Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies. 相似文献
17.
Puay Tang 《The Information Society》1998,14(1):19-31
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means. 相似文献
18.
Milton Mueller 《The Information Society》2001,17(3):151-163
Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP. 相似文献
19.
Prof. Raymond C.K. Chen a neuropsychologist with the CAS Institute of Psychology has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.…… 《中国科学院院刊(英文版)》2008,22(1):15-15
Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology. 相似文献
20.
Prof. SUN Changpu from the CAS Institute of Theoretical Physics coworkers from University of Basel in Switzerland have worked out a way - at least in theory - to split a beam of molecules according to their chirality. The technique involves passing the molecules through three different laser beams is similar to the famous Stern-Gerlach effect whereby a beam of atoms passing through a magnetic field is split in two according to the atoms' spin states 《中国科学院院刊(英文版)》2008,22(1):23-23
Prof. SUN Changpu from the CAS Institute of Theoretical Physics and coworkers from University of Basel in Switzerland have worked out a way --at least in theory --to split a beam of molecules according to their chirality. The technique involves passing the molecules through three different laser beams and is similar to the famous Stern-Gerlach effect, whereby a beam of atoms passing through a magnetic field is split in two according to the atoms＇ spin states （Phys. Rev. Lett. 99 130403）. 相似文献