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81.
卡尔曼滤波器在光电经纬仪中的应用   总被引:6,自引:2,他引:4  
为了解决光电经纬仪电视跟踪系统脱靶量滞后对控制系统跟踪精度及稳定性的影响,将预测滤波技术应用到光电跟踪系统中,提出了极坐标下卡尔曼滤波算法,目标模型采用等速运动并附有时间相关的随机加速度,增加了延时补偿。仿真结果表明,跟踪误差减小,当跟踪目标从视场消失时,控制系统按照预测的目标信息跟踪。  相似文献   
82.
拉刀在刃磨过程中存在不易获得定值前角且会降低刀具硬度等问题,为此设计了拉刀前刀面挤压工艺.该工艺简便易行,一把拉刀可挤压5—8次,效益好。使用证明,经挤压加工后的拉刀加工的零件精度高,且拉刀的使用寿命可提高30%以上。  相似文献   
83.
一种弧焊机器人实时激光扫描视觉系统   总被引:2,自引:0,他引:2  
研制了一种小型高精度弧焊机器人实时激光扫描视觉系统,对其各项性能进行了测试,并进行了抗电弧光干扰试验,结果表明,此系统精度高,抗干扰能力强,检测范围宽,能广泛地应秀于机器人和自动化焊接中。  相似文献   
84.
Previously, researchers raised the accuracy for a robot’s hand to track a specified path in Cartesian space mainly through increasing the number of knots on the path and the number of the path’s segments, which results in the heavier online computational burden for the robot controller. Aiming at overcoming this drawback, the authors propose a new kind of real-time accurate hand path tracking and joint trajectory planning method. Through selecting some extra knots on the specified hand path by a certain rule and introducing a sinusoidal function to the joint displacement equation of each segment, this method can greatly raise the path tracking accuracy of robot’s hand and does not change the number of the path’s segments. It also does not increase markedly the computational burden of robot controller. The result of simulation indicates that this method is very effective, and has important value in increasing the application of industrial robots. Foundation item: Foundation of the Robotics Laboratory, Chinese Academy of Sciences (No. RL200002) Biography of the first author: TAN Guan-zheng, Dr., professor, born in Oct. 1962, majoring in artificial intelligence, robotics and automation.  相似文献   
85.
The techniques for image analysis and classification generally consider the image sample labels fixed and without uncertainties. The rank regression problem studied in this paper is based on the training samples with uncertain labels, which often is the case for the manual estimated image labels. A core ranking model is designed first as the bilinear fusing of multiple candidate kernels. Then, the parameters for feature selection and kernel selection are learned simultaneously by maximum a posteriori for given samples and uncertain labels. The provable convergency Expectation Maximization (EM) method is used for inferring these parameters in an iterative manner. The effectiveness of the proposed algorithm is finally validated by the extensive experiments on age ranking task and human tracking task. The popular FG-NET and the large scale Yamaha aging database are used for the age estimation experiments, and our algorithm outperforms those state-of-the-art algorithms ever reported by other interrelated literatures significantly. The experiment result of human tracking task also validates its advantage over conventional linear regression algorithm. A short version of this paper appeared in ICME07.  相似文献   
86.
Research presented in this paper deals with the systematic examination, development, and evaluation of a novel multimodal registration approach that can perform accurately and robustly for relatively close range surveillance applications. An analysis of multimodal image registration gives insight into the limitations of assumptions made in current approaches and motivates the methodology of the developed algorithm. Using calibrated stereo imagery, we employ maximization of mutual information in sliding correspondence windows that inform a disparity voting algorithm to demonstrate successful registration of objects in color and thermal imagery. Extensive evaluation of scenes with multiple objects at different depths and levels of occlusion shows high rates of successful registration. Ground truth experiments demonstrate the utility of the disparity voting techniques for multimodal registration by yielding qualitative and quantitative results that outperform approaches that do not consider occlusions. A basic framework for multimodal stereo tracking is investigated and promising experimental studies show the viability of using registration disparity estimates as a tracking feature.  相似文献   
87.
省的基本原理及省转移的个案分析   总被引:1,自引:0,他引:1  
分析了省的存在原理和转移原则,并对省转移的实际应用进行了实例对比分析,总结了省道转移中前胸省造型设计的规律,进一步探讨了省在实际设计中的应用规则。  相似文献   
88.
一种识别薄板对接接头的视觉方法   总被引:1,自引:0,他引:1  
对薄板紧密对接接头的识别问题进行了深入的分析,提出了由照明、自适应局部特征提取、全局特征识别和验证融合在一起的视觉识别方法。它克服了电弧光的干扰,识别结果可靠,可以有效地解决薄板紧密对接接头识别这一难题。  相似文献   
89.
This paper deals with the gasless combustion problem in an infinite one-dimensional medium. The possibility of the existence of steadily propagating reaction waves is stated for system models with nonzero reaction rates everywhere but at the boundaries. Two forms for the chemical reaction rate dependence on the temperature are considered: the classical Arrhenius, and a modified Arrhenius incorporating and ignition temperature. The equations for the steadily propagating waves are studied in the phase-plane of the temperature and its derivative. The analysis first addresses the question of whether steadily propagating waves are admissible. Then bounds for the propagation velocity are sought and found. The results of the closed-form analysis are successfully tested against numerical experiments. Non-steady propagation regimes are also found, and regions in the parameter space associated with different asymptotic dynamical behaviour are identified.  相似文献   
90.
针对雷达目标观测和处理在不同的坐标系下完成,本文提出了联合滤波算法来跟踪机动目标。该算法以卡尔曼滤波器为基础,直角坐标系下和极坐标系下的算法相联合,不仅克服了两种坐标系下滤波算法的不足,而且对机动目标有很好的跟踪效果。仿真实验结果表明了该算法的有效性。  相似文献   
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