Resonance method of geophysical signal detection by laser gravitational antennas

We consider the role of an additional mirror (recycling) in the design of long-base gravitational wave laser interferometers for the detection of weak infra-low-frequency geophysical signals by the resonance method     

High frequency scanning response of an APD photocurrent for laser range finder

In this paper, the scanning response of the photocurrent emitted by a large area avalanche photodiode (APD) is studied for a 3D laser camera. This 3D camera is based on a phase-shift laser range-finder to measure distance from 1 to 20 m. To obtain a large field of view of the optical head, a large area APD working as an optoelectronic mixer is used. Photocurrent response versus light spot position above the APD active area is analysed for high frequency measurements. Optoelectronic mixing permits to measure the scanning response phase of the internal photoelectric current. Moreover, it is demonstrated that the signal phase depends on the photoelectric gain. Signal-to-noise ratio and distance measurement error for the 3D camera are then discussed.     

A new scheme of geophysical signal detection with optical gravitational antennas

We suggest a method of detection of quasistatic geophysical signals with long-base gravitational-wave laser interferometric antennas, alternative to the ??free spectrum range?? regime, under optimal alignment of the optical system.     

Peculiarities of null string motion in the gravitational field of a radially expanding or radially collapsing multistring system

We have found a solution to the Einstein equations for the case of radial expansion or radial collapse of a multistring system having a layered structure. It has been shown that the influence of the gravitational field of such multistring system can lead to stable oscillations of a test null string in the vicinity of a fixed (stationary) point in space, which can be regarded as a spatially localized particle with a nonzero effective rest mass. In this case, the ability of multistring systems to create such particles can be considered as a possible alternative to the Higgs mechanism. It has also been noted that for a gas of null strings, creation of particles with nonzero effective rest mass is possible at early stages of the Universe evolution, where due to high pressures and a domain structure of such a gas, mutual penetration of null strings belonging to neighboring domains was unavoidable and could emerge in mass. At later stages, due to expansion of the Universe, such an opportunity could be lost.     

激光跟踪测距仪在体育领域中的应用

介绍了激光的特点及激光跟踪测距仪的工作原理 ,在此基础上 ,设计了一种激光跟踪测距系统 ,对该系统的组成及主要部件进行了阐述 ,给出了该系统的主要性能数据 ,并对该系统在体育领域中的应用前景作了展望。     

DIY基于摄像头的激光测距仪

基于微型计算机摄像头和激光发射器的一种智能距离测试系统设计。利用计算机的高速运算,采用图像识别技术,只用一个摄像和激光笔就可以测出距离。极大地节约了成本和重量,在机器人及飞行器中得到了很好的作用。     

2-Covered paths by a set of antennas with minimum power transmission range

In this paper we describe and solve the following geometric optimisation problem: given a set S of n points on the plane (antennas) and two points A and B, find the smallest radial range r∈^ℜ+ (power transmission range of the antennas) so that a path with endpoints A and B exists in which all points are within the range of at least two antennas. The solution to the problem has several applications (e.g., in the planning of safe routes). We present an O(nlogn) time solution, which is based on the second order Voronoi diagram. We also show how to obtain a path with such characteristics.     

Clustering and line detection in laser range measurements

This article presents two algorithms that extract information from laser range data. They are designed to work sequentially. The first method (dcc) separates the data into clusters by means of a convolution operation, using a high-pass filter. The second one (reholt) performs line detection in each of the clusters previously discovered. The reliability of the algorithms devised is tested on the experimental data collected both indoors and outdoors. When compared with other methods found in the literature, the ones proposed here prove to achieve higher performance.     

Two-mode ILC with pseudo-downsampled learning in high frequency range

In this paper, an iterative learning control scheme that combines the designs in the frequency and time domains is proposed to improve the tracking accuracy. The scheme separates the error signals into low and high frequency band error components and employs different learning mechanisms to deal with these error components, respectively. On the low frequency band, a conventional iterative learning control is used. On the high frequency band, a downsampled learning is implemented to suppress more error components to generate a high tracking accuracy. We will address in detail the issues of signal separation, learning controller design, convergence analysis, and experimental verification of the proposed scheme.     

激光测高仪仿真系统设计

为设计激光测高仪仿真系统,首先分析了设计要求,给出了系统设计方案;然后提出了系统设计的部分硬件选择;并为抑制干扰提出了一些办法。     

激光测距仪在机械手自动更换技术中的应用

设计了一种基于位置敏感器件(PSD)的三角形激光测距仪,测距仪安装在空间机器人的腕部,在机器人工作时对距离和机械手腕的位置与姿态进行检测,激光器发出明亮的红色光斑可作为机器人视觉的基准。     

微型机在前向散射式能见度激光测量系统中的应用

本文简要介绍了前向散射式能见度激光测量系统的组成、工作原理，详细介绍了系统硬件电路的具体实现及软件的设计。     

Identifying rectangles in laser range data for urban scene reconstruction

In urban scenes, many of the surfaces are planar and bounded by simple shapes. In a laser scan of such a scene, these simple shapes can still be identified. We present a one-parameter algorithm that can identify point sets on a plane for which a rectangle is a fitting boundary. These rectangles have a guaranteed density: no large part of the rectangle is empty of points. We prove that our algorithm identifies all angles for which a rectangle fits the point set of size n in O(nlogn) time. We evaluate our method experimentally on 13 urban data sets and we compare the rectangles found by our algorithm to the α‐shape as a surface boundary.     

激光熔覆技术在机械修复中的应用

论述了激光熔覆表面处理技术的原理、特点。阐述了我公司利用激光熔覆表面处理技术修复冶金机械设备零部件失效方式的方法、过程和所取得的效果。与传统的修复技术相比,作者充分肯定了激光熔覆表面处理技术不失为当前机械设备修复的最好技术之一。     

Peculiarities of equilibria in the forbidden-situation games

Continued was a previous study of the peculiarities of the forbidden-situation games that analyzed the guaranteed results for various sequences of the participants’ actions. Consideration now was given to the deformations of the Nash and Pareto equilibria by the mutual actions of the game participants on the set of permissible controls. The general constructions are illustrated by the analytical solutions for the Cournot model of competitive interaction of two manufacturing companies complemented by a constraint on the total raw-material resource.     

Development of a laser range finder for three-dimensional map building in rubble

In order to search and rescue victims in rubble effectively, a three-dimensional (3D) map of the rubble is required. As a part of the national project on rescue robot systems, we are investigating a method for constructing a 3D map of rubble by teleoperated mobile robots. In this paper, we developed a laser range finder for 3D map building in rubble. The developed range finder consists of a ring laser beam module and an omnivison camera. The ring laser beam is generated by using a conical mirror and it is radiated toward the interior wall of the rubble around a mobile robot on which the laser range finder is mounted. The ominivison camera with a hyperbolic mirror can capture the reflected image of the ring laser on the rubble. Based on the triangulation principle, cross-section range data is obtained. Continuing this measurement as the mobile robot moves inside the rubble, a 3D map is obtained. We constructed a geometric model of the laser range finder for error analysis and obtained an optimal dimension of the laser range finder. Based on this analysis, we actually prototyped a range finder. Experimental results show that the actual measurement errors are well matched to the theoretical values. Using the prototyped laser range finder, a 3D map of rubble was actually built with reasonable accuracy.     

Modeling of a scanning laser range sensor for robotic applications

The geometric and noise modeling of a scanning range sensor is described. The parameters of the model are determined from data collected during the calibration of the real sensor. The models are shown to predict range scan results which accurately match those of the real sensor.     

基于频率段的语音识别算法设计与实现

线性预测倒谱参数(LPCC)能很好的体现人的声道特性,而梅尔倒谱参数(MFCC)能很好的模拟人耳的听觉效应。针对MFCC在不同频率段的识别精度不一致和LPCC不能准确模拟人的听觉系统问题,将MFCC参数和IMFCC参数分别作为语音不同频率段的特征参数,结合线性预测参数(LPCC),均衡滤波器的分布,完整覆盖到整个频率段范围。将梅尔倒谱参数和线性预测参数结合起来作为语音识别的特征提取参数。实验结果表明,改进之后的算法从效率上和识别率上都有不同程度的提高。     

A novel MEMS tunable antenna with wide tuning range of frequency

In this paper a novel MEMS tunable CPW antenna with wide tuning range of frequency is presented. The antenna’s frequency tuning range increment is achieved by loading three novel large tuning range capacitors at radiation edge of antenna patch. Two techniques are employed for increasing the capacitors tuning range. First, dual gap technique is used to overcome the pull-in limitation and then two lateral beams are added in order to parallel movement of capacitive plate which increases the capacitance value. The simulation result shows that the resonance frequency tuning range of antenna increased from 1.96 GHz loaded by traditional capacitor to 6.89 GHz using the new capacitor structure. Also in resonance frequency, the antenna has a good impedance matching with transmission line even in high capacitance values.     

基于静态图像的CCD激光测距方法的研究

随着测量技术的迅猛发展，现令对三维深度的测量常用激光测距法。然而，固定摄像机电荷耦舍型CCD器件是一种集成电路，通过CCD可以实现光电转换信号储存、转移（传输）、输出、处理以及电子快门等一系列功能，CCD数据率可调。因此，CCD可适用于动态、静态等各种条件下的尺寸测量。鉴于此，本文从物理光电学及数学角度，采用CCD激光测距法，推导了基于静态图像的CCD激光测距的通用公式。该算法的最大优点是无需进行复杂的迭代计算。大大降低了计算量，且有效的提高了测量精度。分析表明：该方法计算简单、易于实现、实用价值高。