基于模糊PID控制器的网络控制系统仿真研究

为了研究网络控制系统的特性,利用TrueTime工具箱来搭建网络控制系统的仿真模型。分别采用一般PID控制器的网络控制系统模型和采用模糊PID控制器的网络控制系统模型进行仿真。仿真结果表明：当网络控制系统存在时延时,采用模糊PID控制器的系统输出曲线超调量小,调节时间短,提高了系统的稳定性。     

基于模糊自适应PID的转台位置控制系统设计

建立了驱动器-电机-减速器和转台的数学模型及其Simulink仿真模型。介绍了模糊自适应PID控制器的设计方法,通过Matlab模糊工具箱实现了模糊PID控制系统的仿真。仿真结果表明用模糊自适应PID控制转台位置伺服系统,具有超调小、响应快、精度高、鲁棒性强等优点。将模糊控制方法与PID控制结合起来,用模糊推理方法进行PID参数的在线自整定,并取得了良好的效果。     

F-PID复合控制器在闭环光纤陀螺仪中的应用

陀螺仪是惯性系统的核心部件，目前数字干涉式光纤陀螺（IFOG）以其宽带宽，响应速度快的优点成为首选。IFOG可以看作一个数字控制系统，因此，其动态性能受控制系统设计的影响。现根据此类陀螺的工作原理，推导出系统离散传递函数。将模糊控制器与PID控制器相结合，设计一种新型的F?PID复合控制器取代传统的PID控制器。仿真结果显示，采用F?PID控制器的光纤陀螺系统可以有效地缩短调节时间，减小超调量，并且具有强的抗干扰能力。     

电烤箱温度系统的模糊自整定PID控制方法的研究

提出利用模糊自整定PID控制器实现对电烤箱温度控制的方法,将模糊控制器和PID控制器结合在一起,利用模糊逻辑控制实现了控制器参数在线自调整,完善了传统PID控制器的性能,提高了系统的控制精度.并把MATLAB中的Fuzzy Toolbox和Simulink结合起来,方便实现了自整定模糊PID控制系统的计算机仿真.     

模糊PID在热水锅炉温度控制系统中的应用

模糊PID控制方法在热水锅炉温度控制系统中的应有有着十分明显的优势。本文首先概述了模糊PID控制,然后分析了锅炉温度控制系统控制器的设计,最后在探讨了模糊PID控制规则的基础上,对参数自整定的模糊PID控制器的设计和仿真研究做了研究。     

机械手臂转角自动控制器设计与改进

机械手臂的诞生具有解放生产力的现实意义,机械手臂转角控制格外重要,因而,采用PID控制设计机械手臂转角自动控制器。所设计的自动控制器具有四个自由度,由PLC、步进电机和SH-215B步进电机驱动器组成,步进电机驱动器从PLC中接收转角命令,转角命令中蕴含的定位信息由步进电机中BCE58K20增量式光电编码器给出,进而控制机械手臂转角动作。PLC在使用普通PID控制下,积分控制环极易超调,采用模糊技术将普通PID控制模糊化,借助分离技术降低积分超调对机械手臂动作的影响,提出模糊分离PID控制。实验结果表明,与采用其他控制策略的自动控制器相比,采用模糊分离PID控制的自动控制器自由度更加灵活。     

模糊PID励磁控制器的仿真研究

针对常规PID控制器不能在线整定参数,模糊控制器对复杂的和模型无法建立的对象能够进行简单有效的控制,将常规PID与模糊控制器结合,综合其优点,构造2种模糊PID控制器。利用Matlab对两种控制器在自动励磁控制系统中进行仿真,结果表明两种模糊PID励磁控制器有很好的控制效果。     

自适应模糊PID控制的太阳光跟踪伺服系统

针对太阳光跟踪伺服系统中应用的传统PID控制过程中的一些问题,本文通过对自适应模糊PID控制系统的分析,设计了双轴跟踪伺服系统自适应模糊PID控制器,并在Simulink环境中建立方位角跟踪传动机构仿真模型且完成仿真。仿真结果表明,太阳光跟踪伺服系统自适应模糊PID控制器较传统PID控制器具有较强的稳定性、适应性与鲁棒性,这在太阳光跟踪伺服系统控制领域具有重要的实用价值与应用空间。     

静电放电测试仪低气压控制系统设计与研究

为了在静电放电测试仪中定量研究不同气压对非接触静电放电的影响,以STM32为核心设计了低气压自动控制系统,包含LCD、触摸屏、信号采集、驱动电路等硬件模块。分析控制系统的数学模型,针对系统非线性、时变性的特点设计以自适应模糊PID为核心的控制算法。由于控制系统的执行元件质量流量控制器输出受限易产生积分饱和,采用遇限削弱积分法对控制算法进行改进。通过Malab对改进后的自适应模糊PID和PID的控制过程进行仿真,结果表明自适应模糊PID控制具有更好的动态性能。     

异步电机的模糊PID矢量控制

为了提高异步电机转速性能,文章在原矢量控制系统的基础上,将传统的转速PID控制器转换为模糊自适应PID控制器,然后利用Matlab/Simulink搭建了一种基于三相异步电动机转速控制的模糊PID系统,并分别使用常规PID控制器与模糊PID控制器进行控制。仿真结果表明,采用模糊控制能使系统取得较好的控制性能并具有较强的鲁棒性。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.