基于电磁微马达的移动微机器人驱动控制

介绍一种基于MEMS技术制作的电磁微马达驱动的毫米级移动微机器人及其控制方案。该微型机器人体积为 9.5mm× 9.5mm× 9.5mm ,共有 3个微马达 ,两个用于轮子驱动 ,另外一个通过 3∶1的减速装置来控制微机器人全方位转动。微马达的直径只有 5mm ,是由微细加工工艺制作的。文中设计了一种新颖的控制电路 ,其核心使用微控制器 (MCU)AT90S85 15 ,通过键盘可以实现微机器人前进、后退、左转、右转和加速、减速 6种动作 ,并介绍了微马达的驱动控制方法和程序设计     

Electromagnetic Two-Dimensional Scanner Using Radial Magnetic Field

In this paper, we present the design, fabrication, and measurement results of a two-dimensional electromagnetic scanning micromirror actuated by radial magnetic field. The scanner is realized by combining a gimbaled single-crystal-silicon micromirror with a single turn electroplated metal coil, with a concentric permanent magnet assembly composed of two concentric permanent magnets and an iron yoke. The proposed scanner utilizes the radial magnetic field rather than using a lateral magnetic field oriented 45deg to the horizontal and vertical scan axes to achieve a biaxial magnetic actuation. The single turn coil fabricated with electroplated copper achieves a nominal resistance of 1.2 Omega. A two-dimensional scanner with mirror size of 1.5 mm in diameter was fabricated. Maximum optical scan angle of 8.8deg in horizontal direction and 8.3deg in vertical direction were achieved. Forced actuation of the gimbal at 60 Hz and resonant actuation of the micromirror at 19.1-19.7 kHz provide slow vertical scan and fast horizontal scan, respectively. The proposed scanner can be used in raster scanning laser display systems and other scanner applications.     

Navigation Using an Environmental Magnetic Field for Outdoor Autonomous Mobile Robots

GPS and laser range finders are generally utilized in current robot navigation. However, information from the magnetic field and electronic compass is not, since it is dynamically changing at every position. In this paper, the relationship between the intensity of a magnetic field in the environment and its position is taken into account by utilizing a three-axis magnetic sensor to scan the magnetic field in the environment to build a database. The mobile robot navigates by performing trajectory tracking based on the database. The experimental results show that by applying the proposed method, the mobile robot is able to navigate in an outdoor environment with reliable accuracy.     

一种用于微型工厂的毫米级全方位移动微机器人设计与分析

介绍了一种毫米级全方位移动微机器人,尺寸为9mm*8mm*8mm。独特的双轮设计实现了转向时与地面的滚动摩擦。驱动器为3个直径2mm的电磁微马达,其中2个用于直线驱动,另一个用于转向。运动受力分析揭示了微马达驱动力矩与双轮结构尺寸及各种摩擦之间的关系。仿真计算及实验表明微机器人具有良好的负载能力,能够满足微型工厂中的搬运操作要求。     

毫米级全方位移动微型装配机器人设计、运动学分析与控制

介绍了一种用于微型工厂的毫米级移动微装配机器人,其具有独特的全方位运动结构．微机器人由4个直径3 mm的电磁微马达驱动,并装备有一对微型夹钳．通过分析运动学矩阵的秩,证明了微机器人的全方位特性,并建立了微夹钳的运动学方程．设计了基于计算机视觉的微机器人控制系统,给出了微机器人定位和驱动方法．实验证明了微机器人的负载能力、机动性以及控制系统的有效性．     

297 Distinct Cell Lines: A High-Content Analysis Assay and a Full-Automation Design Solely Using Noncontact Liquid Dispensing

This review assesses the quality of the data acquired over a 13-week period from a High-Content Analysis screening project that used 297 unique cell lines. This article also evaluates the proficiency of a “tipless” (i.e., does not use disposable tips) full-automation design used for this project that prioritizes intralab system mobility and system configuration mutability. The request to assay a large number of cell lines with poorly characterized growth rates led us to devise an MDS PharmaServices, Inc. proprietary algorithm in an effort to select the proper cell plating density for each cell line. The performance metrics include coefficients of variation (CVs) of Controls for the cell plating data and Data Set Mean CVs for assessing replicate propinquity (i.e., how close the replicates are to each other). The performance of the automation system and our algorithm for this project produced data of superior quality.     

手机二维码在国内的发展及应用

手机二维码是将二维条码和无线移动终端结合的产物,它一方面具有二维条码的特点,另一方面利用移动网络实现手机增值服务.文章介绍了手机二维码在国内的发展现状和成功应用案例.     

Two-Dimensional Analysis of Electrokinetically Driven Out-of-Plane Vortices in a Microchannel Liquid Flow Using Patterned Surface Charge

The technology developed for photolithographically patterning the electric surface charge to be negative, positive, or neutral enables the realization of complex liquid flows even in straight and uniform microchannels with extremely small Reynolds number. A theoretical model to analyze a steady incompressible electrokinetically driven two-dimensional liquid flow in a microchannel with an inhomogeneous surface charge under externally applied electric field is derived. The flow field is obtained analytically by solving the biharmonic equation with the Helmholtz-Smoluchowski slip boundary condition using the Fourier series expansion method. The model has been applied to study three basic out-of-plane vortical flow fields: single vortex and a train of corotating and a series of counterrotating vortex pairs. For model verification, the solution for the single vortex has been tested against numerical computations based on the full Navier-Stokes equations revealing the dominant control parameters. Two interesting phenomena have been observed in out-of-plane multivortex dynamics: merging of corotating vortices and splitting of counterrotating vortices. The criteria for the onset of both phenomena are discussed     

Microelectromechanical Resonator Characterization Using Noncontact Parametric Electrostatic Excitation and Probing

A noncontact electrostatic probing technique using a scanning probe microscopy cantilever is shown to actuate and detect the resonant behavior of a micromachined resonator. The method is capable of characterizing a resonator with resonant frequency much greater than that of the cantilever. The coupled oscillator model developed for this system describes the resonant response of the test resonator as detected through the probe, including the fourth-power dependence on the probe drive voltage. The veracity of this model is demonstrated through comparison with experimental data obtained from a test resonator with a resonant frequency ten times greater than the resonant frequency of the probe cantilever. This technique yields a straightforward determination of the resonant frequency and quality factor of a micromachined resonator, avoiding limitations due to optical interference and any reliance on a supporting circuitry.     

基于二维直方图和模糊熵准则的阈值化方法

图像分割是图像分析、识别和理解的基础。图像分割主要是指将图像分成各具特性的区域并提取出感兴趣目标的技术,其研究多年来一直受到人们的高度重视;阈值化法是图像分割的一种重要方法,在图像处理与识别中广为应用;针对图像分割中细节往往被忽略导致后续处理困难的问题,基于模糊关系和最大模糊熵原理提出了一种阈值化方法,对二维直方图进行模糊分割;为了获得图像分割中的细节,提出的方法根据最大熵原则自动确定模糊区域和门限,进而获得二维模糊熵和遗传算法最优解,最后获得图像细节;通过对不同灰度水平和颜色类型图像进行实验比较,实验结果表明提出的方法优于二维非模糊方法和一维模糊熵分割法,得到该方法在图像分割中获得细节的结论。     

Design and Optimization of an Omnidirectional Permanent-Magnetic Wheeled Wall-Climbing Microrobot with MEMS-Based Electromagnetic Micromotors

The paper presents a compact omnidirectional permanent-magnetic wheeled wall-climbing microrobot. A millimeter-sized axial flux electromagnetic micromotor based on MEMS technology has been specially fabricated for the microrobot and its size is 6.8 mm × 7.8 mm × 3.9 mm. A novel permanent-magnetic wheel is designed, which is directly integrated with the stators and rotor of the electromagnetic micromotor. The omnidirectional wall-climbing mechanism is realized by a set of steering gears and three standard permanent-magnetic wheels. By static and dynamic force analysis of the microrobot, the required magnetic force and the required torques for its translational and steering movements are derived. To reduce the unnecessary torque consumption of the microrobot, its structural parameters are optimized in combination with its design constraints by ANSOFT and Pro/Engineer simulation. A prototype of the proposed microrobot with the maximum designed load capacity of 3 g is developed, whose size is 26 mm in diameter and 16.4 mm in height. Experimental and simulation results demonstrate the feasibility of these concepts.     

移动机会网络中接触时间感知的协作缓存策略

数据访问效率一直都是移动机会网络研究中的一个备受关注的问题.协作缓存技术经常被用来提高网络数据访问效率,但是该类网络中节点的强自主移动性和有限的接触时间使得传统的缓存技术无法得到有效应用.首先提出一个新的度量节点在协作缓存中重要程度的指标,即节点重要度.基于此指标,利用贪心算法选择初始缓存节点;利用缓存节点相遇的机会,进行缓存数据的主动再分配.为了适应节点间有限的接触时间,提出了数据分片策略,并使用随机线性网络编码方法对分片进行编码,以解决数据恢复时的赠券收集问题.此外为每个节点确定了缓存边界来限制缓存数据量,从而合理利用缓存空间.最后,通过实验验证了提出的缓存协议能够有效地提高数据访问效率.     

Visual Contact Angle Estimation and Traction Control for Mobile Robot in Rough-Terrain

For a wheeled mobile robot traversing a rough terrain, knowledge of terrain variables is very important for developing effective traction control algorithms. A key variable of the most prevalent information that should be taken into account is the contact angle between the robot wheels and the ground. This paper presents an algorithm for visual estimation of wheel-ground contact angle on uneven terrain. We call it the Visual Contact Angle Estimation (VCAE) method. Given a white LED light source, a monocular camera is required to be mounted on the front wheel and the rear wheel respectively, with a field of view containing the wheel-ground contact interface and its location relative to the wheel is known and fixed during robot travel. This arrangement is used to measure the contact angle with an edge detection strategy. Then a traction control methodology based on multi-objective optimization is presented. This exploits the wheel-ground contact angle obtained in the VCAE system to improve ground traction and reduce power consumption. Simulation and experiment results for a wheeled robot traversing a symmetrical uneven testbed demonstrate the effectiveness of the VCAE method and traction control algorithms.     

使用重复播种和Golomb编码的二维测试数据压缩

提出了一种用于SOC测试的二维测试数据压缩方案．先利用线性反馈移位寄存器重复播种技术,对带有无关位的测试向量进行压缩,并获得种子差分序列;然后用Golomb编码的方法对其作进一步的压缩;同时给出了Golomb码参数。的确定方法和相应的二维解压结构、实验结果表明,该方案在保证较高故障覆盖率的前提下,既能显著地减少测试序列长度、缩短测试时间,又能有效降低对测试数据带宽的要求．     

移动Agent在QoS中的应用

Qos是近来网络技术研究的一个热点,而RSVP是目前流行的几种Qos协议之一,它能够很好地获得服务质量。但是由于目前很多路由器不完全支持RSVP,使得服务会被退回而尽力转发,因此很难保证端到端的服务质量。本文在分析QoS的基础上,提出了结合Agent采保证Qos的方法,运用移动Agent结合RSVP来解决隧道问题。     

基于Kerberos协议的移动网络鉴别技术

提出了一种方法，通过间接客户／代理模型把kerberos协议引入移动环境，从而为移动网络提供安全鉴别。该方法包含一个可移植的代理模块(不要求其可靠)和一个可运行在移动设备或IC卡上的轻型客户端模块。这种功能分离模式使Kerberos协议能比较容易地安装到因特网服务提供设备或移动计算设备上。同时也论证了本方法至少达到同Kerberos协议一样强的安全性。     

智能Agent在行车记录分析系统上的应用

本文介绍了行车记录仪关键组成技术,以及智能Agent行车记录仪系统轨迹处理上的优化作用.为智能Agent在行车记录领域上的应用提供了思路,是智能交通的一个组成部分.     

Laser Pose Estimation and Tracking Using Fuzzy Extended Information Filtering for an Autonomous Mobile Robot

This paper presents methodologies and techniques for posture estimation and tracking of an autonomous mobile robot (AMR) using a laser scanner with at least three retro-reflectors. A three-point laser triangulation method is presented to find an initial posture of the robot and then a fuzzy extended information filtering (FEIF) method is used to improve the accuracy of the robot’s posture estimation. With the odometric information from the driving wheels, a FEIF-based posture tracking algorithm is proposed to continuously keep trace of the robot’s posture at slow speeds. Simulation and experimental results are conducted to show the efficacy and usefulness of the proposed methods.     

在VC中使用Cstatic进行界面编程

介绍了以VC 6.0为开发工具,以开发电子阅览室门禁程序的界面为例,重点介绍CStatic类的派生类Clabel,通过对CLabel类方法的调用,在不同的静态文本控件实现各自的文字风格,同时,使静态文本控件背景透明.