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 共查询到11条相似文献,搜索用时 15 毫秒
1.
A network for displaying the velocity signal of a target edge which has larger velocity than the background was proposed and designed based on an insect visual system. In the insect visual system, the velocity signals generated by the background are inhibited by the signals generated by averaging the velocity signals from each cell and can only display the velocity signals of the target. The proposed network was constructed with simple analog circuits. The measured results of the test chip fabricated with the 1.2$mUm complementary metal-oxide-semiconductor (CMOS) process showed that the edge detection circuit inserted to the first stage of the proposed network can detect the edge position. It was apparent from the measured results of the test circuit constructed with discrete metal-oxide-semiconductor (MOS) transistors that the proposed unit circuit constructing the network can generate the velocity signals by inputting the edge signals. The results with the simulation program with integrated circuit emphasis (SPICE) showed that the proposed network can only display the velocity signals of the target edges but not those of the background. Thus, it was clarified that the various motion directions of the target can be detected independent of the background by using the proposed network.  相似文献   

2.
We proposed an analog network for motion detection of an approaching object with simple-shape recognition based on the visual systems of lower animals. Locusts can detect an approaching object by performing a simple process in a descending contralateral motion detector (DCMD) existing in their brain, which senses the increase in size and expansion velocity of the image projected on a retina just before collision. The responses correspond to the approaching velocity and direction. Frogs can recognize a simple shape by performing a simple process in a tectum and thalamus existing in their brain based on retinal information; this is called the Ewert von Seelen model. The proposed network was constructed with simple analog metal-oxide-semiconductor (MOS) circuits. Simulation results with a simulation program with integrated circuit emphasis (SPICE) showed that the network was able to detect the approaching velocity and direction, and also recognized simple shapes such as a circle, square, triangle and rectangle.  相似文献   

3.
We proposed in this research a novel two-dimensional network based on the frog visual system, with a motion detection function and a newly developed simple-shape recognition function, for use in object discrimination by integrated circuits. Specifically, the network mimics the signal processing of the small-field cell in a frog brain, consisting of the tectum and thalamus, which generates signals of the motion and simple shape of an object. The proposed network is constructed from simple analog complementary metal oxide semiconductor (CMOS) circuits; a test chip of the proposed network was fabricated with a 1.2 μm CMOS process. Measurements on the chip clarified that the proposed network can generate signals of the moving direction, velocity, and simple shape, as well as perform information processing of the small-field cell. Results with the simulation program with integrated circuit emphasis (SPICE) showed that the analog circuits used in the network have low power consumption. Applications of the proposed network are expected to realize advanced vision chips with functions such as object discrimination and target tracking.  相似文献   

4.
We proposed in this study a novel analog complementary metal oxide semiconductor (CMOS) circuit for generating a motion signal when an object moves, which is a simple structure. The proposed unit circuit was constructed using a previously proposed edge detection circuit and a novel proposed circuit for generating a motion signal which accepts an edge signal. The part for generating the motion signal was constructed using six metal oxide semiconductor (MOS) transistors and one capacitor. Results obtained by the simulation program with integrated circuit emphasis (SPICE) and the measured results of a test circuit constructed with discrete MOS transistors and the test circuit fabricated with a 1.2 μm CMOS process showed that the proposed unit circuit can output pulsed current (motion signal) when an object moves on the circuit. It was clarified from the SPICE results that the two-dimensional network constructed with proposed unit circuits can output motion signals. The size of the novel unit circuit is expected to be about 110 × 110μm2 obtained by the 1.2 μm CMOS process. It is possible to arrange 90 × 90 unit circuits on a chip which has an area of 1 × 1cm2. The aperture ratio is expected to be about 21%, which is twice as large as that of the previously proposed circuit. An integrated circuit for image processing in real time can thus be realized by applying the two-dimensional network constructed with the proposed circuits.  相似文献   

5.
A simplified model was proposed for the formation of edge signals and generation of motion signals of a target based on the information processing mechanisms of outer and inner retinas of a vertebrate. Analog metal-oxide-silicon (MOS) integrated circuits were designed based on the model. Simulation program with integrated circuit emphasis (SPICE) simulation results showed the performance of local adaptation over a wide dynamic range in the outer retinal circuit and generation of the velocity signal of a moving edge in the inner retinal circuit. Preliminary experimental results showed local adaptation in a given input range in the outer retinal circuit and the generation of motion pulsed signals in the inner retinal circuit.  相似文献   

6.
A network for motion detection of an approaching object without influence of the moving background was proposed based on the insect visual system. The two-dimensional array of the analog complementary metal oxide semiconductor (CMOS) circuits for extracting the edge signals of the approaching object without outputting those of the moving background was inserted at the first stage of the network. At the next stage, analog CMOS circuits for detection of approaching velocity and direction, which accept the extracted edge signals, were inserted based on the locust vision system. A chip of the proposed network was fabricated with the 1.2 mm CMOS process. It was clarified from the measured results and the simulation results with the simulation program with integrated circuit emphasis (SPICE) that the two-dimensional circuits of the first stage can only generate the signals of target edges. The measured results showed that the chip can detect the approaching velocity and direction of the target in the image which contains the moving background.  相似文献   

7.
We designed an integrated circuit for edge detection of a two-dimensional image based on the vertebrate outer retina, which has wide dynamic range in image processing. The unit circuit is simple, and operates as a current-mode analog metal-oxide-semiconductor (MOS) circuit. In order to extract edges from an image composed of bright and dark domains, the circuit realizes a function called local adaptation in which the sensitivity adapts to local brightness of the image. Simulation results, using the simulation program with integrated circuit emphasis (SPICE), of two-dimensional Gaussian-distributed images in which the intensity ranged over four orders of magnitude, showed the local adaptation. As a result, the intensity of output images was in the range of one order of magnitude. Furthermore, as the simulation result of real images, it was shown that edges in the dark domain, which was five times darker than the bright domain, were successfully detected as the bright domain in which input photocurrents ranged over two orders of magnitude.  相似文献   

8.
Inspired by a mechanism of biological vision systems, a model and a network of analog metal oxide semiconductor (MOS) circuits are proposed which display an optical flow with local adaptation to the relative velocity of a background image. A function of displaying an optical flow successfully worked as a result of simulations using the simulation program with integrated circuit emphasis (SPICE). A function of varying an optical flow at a certain instant by local adaptation was also demonstrated. The proposed network is suitable for the realization of a large-scale integrated circuit (LSI), which displays an optical flow with local adaptation to the local velocity of a background.  相似文献   

9.
X射线脉冲星导航探测器性能研究   总被引:1,自引:1,他引:0  
  相似文献   

10.
光纤电流互感器日益成为电力系统中最重要的设备,在实用化研究中,光纤电流互感器的检测精度是重要的指标之一,而被测电流的谐波和光纤电流互感器内部的噪声往往影响其测量的准确性。因此对光纤电流互感器谐波的检测以及对其解调算法实用性的验证非常重要。为进一步的谐波治理提供依据及验证解调算法能否有效运用问题,在详细分析现有的谐波检测理论和两种解调算法原理的基础上,设计了一种基于虚拟仪器LabView的光纤电流互感器谐波检测及解调算法测试一体化系统,在快速检测电流各次谐波电平的同时解调出被测电流的信息并对比验证两种解调算法的可行性与优越性,验证结果表明第二种解调算法的精度明显优越于第一种解调算法,更能适用于光纤电流互感器的信号解调。  相似文献   

11.
郭竞杰 《应用声学》2012,(6):1562-1564,1568
提出了一种采用SOPC技术在单个FPGA芯片上构建的新型实时PH曲线运动控制器的架构;该运动控制器在QuartusⅡ9.0中设计,由一个NiosⅡ软核处理器和多个功能模块构成;它通过采用二次插补方式以减少PH曲线插补的计算量;NiosⅡ处理器执行主控程序和PH曲线粗插补算法,FPGA硬件逻辑执行精插补算法并输出两组用于控制执行机构(XY工作台)的控制脉冲;实验数据表明,该运动控制器完成恒进给速度的单次PH曲线插补的平均耗时均小于2ms,终点坐标的定位误差均低于0.0079mm。  相似文献   

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