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71.
基于参考模型的超声电机模糊自适应控制 总被引:1,自引:0,他引:1
针对由日本新生公司生产的USR系列超声电机构成的速度伺服系统提出了一种新的控制方案——基于参考模型的模糊自适应控制。该控制器由参考模型、PI控制器、模糊自适应调节器构成,PI控制器的比例系数的增量△Kp和积分系数的增量△Ki根据模糊自适应调节器模糊推理的结果确定,使得控制器的参数能够随着被控对象参数的变化而改变,从而保证系统的响应跟踪参考模型的输出响应。实验结果表明该控制方案优于一般的PI控制器和模糊PI控制器,并且简单易行,通用性强。 相似文献
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73.
利用情报雷达伺服系统的速度反馈信号,构成一个位置稳定回路,解决情报雷达伺服系统输入信号为零时,雷达天线产生缓慢漂移的问题。采用该方法,虽然舍弃了由位置传感器构成位置回路的常规设计方法,但情报雷达伺服系统仍然有较高的定位精度。仿真结果说明该设计方法是可行和有效的。 相似文献
74.
基于自由空间光通讯(FSO)技术和OCDMA编码调制技术实现了自由空间语音异地通讯,具有高速高效、抗干扰能力强、保密性好等优点。系统设计采用双CPU结构,主控CPU单元主要实现语音采集、信号编码、数字调制等功能,辅单片机则为FSO关键技术ATP伺服系统的控制核心,论述了设计要点,并给出了测试结果。 相似文献
75.
阐述了基于全数字伺服控制单元的位置控制系统的特点,并且对运动控制算法进行分析,介绍了欧姆龙公司最新推出的新型全数字交流伺服控制单元MCW151的原理和性能,阐述基于交流伺服控制单元MCW151的位置控制系统的特点,并且设计了一种新的高精度伺服控制系统。 相似文献
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78.
We implement a video object segmentation system that integrates the novel concept of Voronoi Order with existing surface optimization techniques to support the MPEG-4 functionality of object-addressable video content in the form of video objects. The major enabling technology for the MPEG-4 standard are systems that compute video object segmentation, i.e., the extraction of video objects from a given video sequence. Our surface optimization formulation describes the video object segmentation problem in the form of an energy function that integrates many visual processing techniques. By optimizing this surface, we balance visual information against predictions of models with a priori information and extract video objects from a video sequence. Since the global optimization of such an energy function is still an open problem, we use Voronoi Order to decompose our formulation into a tractable optimization via dynamic programming within an iterative framework. In conclusion, we show the results of the system on the MPEG-4 test sequences, introduce a novel objective measure, and compare results against those that are hand-segmented by the MPEG-4 committee. 相似文献
79.
It will provide us an effective method to study the color perception of the elderly if we can employ for young subjects a
pair of glasses with color property chosen to simulate that of the elderly. One problem has to be solved before using such
glasses based on the concept of the recognized visual space of illumination, that is, the size of the glasses. When a piece
of a white paper is seen through a yellow filter in a room, it naturally appears yellowish. But if the observer uses the filter
to cover his/her eyes entirely the white paper returns to its original white; this is known as color constancy. Between these
two extreme cases, the color is expected to change from yellow to white. Chromaticness and hue of an achromatic test chart
of a small or large size were determined by the elementary color naming method when the chart was seen monocularly through
a red, yellow, green or blue filter, respectively, placed at various distances from the eyes. Chromaticness was large at around
40% when the visual field through the filter was equal to or smaller than the test chart, but it rapidly decreased when the
visual field extended over the test chart so that objects other than the test chart were included in the visual field. It
decreased to almost zero when the filter was about 5 cm or less away from the eye. It was concluded that we do not necessarily
have to use goggles to cover the entire visual field but can use a normal pair of glasses made of colored filters for young
subjects to study the color perception of the elderly with understanding that the study is only for the color perception experienced
while wearing the glasses. 相似文献
80.
2D Model-Following Servo System 总被引:2,自引:2,他引:0
This paper gives, in view of the feature of practical 2D (2-dimensional) systems, a formulation of the 2D model-following servo problem for the case where one of the independent variables of the considered 2D systems is unbounded and the other one is bounded. That is, to determine a control input such that the outputs of a given 2D plant asymptotically track, with tracking error as small as possible, the (step) response of a given 2D model system as the unbounded variable approaches infinite. It is shown that this problem under a specified quadratic performance index can be transformed into a 1D LQR problem, and thus can be solved by the well-known 1D approaches. The relation between the solvability condition obtained for the equivalent 1D LQR problem and the practical stabilizability and detectability of the original 2D plant is clarified. Its application to the design of non-unit memory linear multipass processes is also shown. Finally, a numerical example for metal rolling process is given to verify the effectiveness. 相似文献