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91.
夏天维  侯翔 《应用声学》2015,23(1):173-175
针对足球机器人比赛时的模型变化及其环境噪声先验估计不准确的问题,提出一种基于自适应卡尔曼滤波的足球机器人视觉跟踪算法。该算法将一种基于减背景的运动目标识别的方法与自适应卡尔曼滤波跟踪模型进行结合,对背景进行实时更新,并通过形态学滤波去除残留的小区域,从而准确的识别运动目标,通过自适应的在线调整运动模型参数来保证模型预测值的准确性,进而提高了目标跟踪时的匹配效率,实现了目标的精准、迅速跟踪。通过实验证明,该算法是很有效的,具有推广价值。  相似文献   
92.
In this work, two special high-gain tracking differentiators are proposed. By using an ingenious technique which is based on the Taylor expansion, the time lagging phenomenon of the traditional high-gain differentiator is reduced effectively. Therefore, the differentiation exactness of the proposed differentiator is much higher than that of the traditional high-gain tracking differentiator.  相似文献   
93.
A two-beam laser triangulation method has been proposed to measure the position of a moving object. The method uses two parallel laser beams to judge the moving direction of an object, allowing us to track it and measure its positions. An uncertainty of 0.2 mm for a measurement range of 50 mm has been obtained. This tracking measurement capability is useful in the calibration of the position of a moving robot arm.  相似文献   
94.
激光干涉仪应用于无导轨测距的研究   总被引:5,自引:0,他引:5  
邱宗明  郭彦珍  李信 《光子学报》2001,30(7):882-884
本文提出了一种使用外差激光干涉仪实现无导轨测距的方法.该方法动态跟踪测量反射镜,使测量信号不中断,实现反射镜在一定范围内的非直线运动.这样,拥有双频激光干涉仪的用户,再添置一台比较简单的跟踪装置,即可用于无导轨测距,测量精度可远高于通用测距仪,为大型设备现场组装和安装提供了新方法.本文介绍了工作原理及实验情况.  相似文献   
95.
郭丽霞  李长乐 《光子学报》1996,25(10):924-927
本文介绍一种用于电视跟踪系统的全视场捕获模块,在背景较为单调的情况下,它可以在一个电视场的时间内,在全视场范围内自动捕获目标,该模块还具有波门跟踪功能。文中给出了模块的具体实现及外场试验结果。  相似文献   
96.
Multiresolutional signal processing has been employed in image processing and computer vision to achieve improved performance that cannot be achieved using conventional signal processing techniques at only one resolution level[1,2,5,6]. In this paper,we have associated the thought of multiresolutional analysis with traditional Kalman filtering and proposed A new fusion algorithm based on singular Sensor and Multipale Models for maneuvering target tracking.  相似文献   
97.
梁国龙  杨春  陈晓忠  王燕 《应用声学》2005,24(5):300-304
同步水声跟踪定位系统通过时延测量进行定位,当信号传播时延大于脉冲重复周期时,就会出现距离模糊。距离模糊是远程高帧率定位系统不可避免的问题。以往多采用硬件方法抗模糊,使得系统趋于复杂。本文提出了两种软件抗模糊方法:举手表决法和参考位置标示法,前者利用真解的一致性抗模糊,无需任何先验信息;后者利用目标的参考位置抗模糊,需要目标初始就位点这一先验信息。文中给出了算法原理和适用条件。软件抗模糊方法简化了系统设备,海试结果验证了算法的有效性。  相似文献   
98.
光电经纬仪的跟踪误差及其检测   总被引:2,自引:2,他引:0  
田少文  马彩文 《光子学报》1997,26(11):1041-1045
本文开头指出了跟踪性能是光电经纬仪第一重要技术指标,接着叙述了跟踪原理和跟踪误差的检测方法,并对跟踪误差进行了较深入的分析讨论文章最后,将跟踪误差分门别类,介绍了降低跟踪误差,提高跟踪性能的途径。  相似文献   
99.
Vinod B Johri 《Pramana》2002,59(3):L553-L561
We present a realistic scenario of tracking of scalar fields with varying equation of state. The astrophysical constraints on the evolution of scalar fields in the physical universe are discussed. The nucleosynthesis and the galaxy formation constraints have been used to put limits on Ωφ and estimate ɛ during cosmic evolution. Interpolation techniques have been applied to estimate ɛ ⋍0.772 at the present epoch. The epoch of transition from matter to quintessence dominated era and consequent onset of acceleration in cosmic expansion is calculated and taking the lower limit Θ n /0 =0.2 as estimated from SN e I a data, it is shown that the supernova observations beyond redshift z=1 would reveal deceleration in cosmic expansion.  相似文献   
100.
In the present work a numerical study was carried out to investigate the inclusion behaviour in a four strand asymmetric billet caster tundish. A parameter called separation efficiency was used to compare inclusion behaviour quantitatively. An open source CFD code called OpenFOAM was used to model the inclusions through Lagrangian Particle Tracking approach. First, the Lagrangian particle class was defined in the existing simpleFoam solver of the OpenFOAM and the same customized solver was used to track particles in the already obtained velocity field. Inclusions were modelled as spheres and various forces acting were also considered. Present numerical results were validated using available experimental results and found to be in good agreement. Further, such inclusion behaviour was also extended for a real industrial case tundish. Inclusion flotation characteristics in thermally induced flow was analyzed in detail. This is, perhaps, for the first time such an exhaustive study on inclusion analysis being reported considering the forces acting on the inclusions particles and with OpenFOAM.  相似文献   
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