机电一体化实用技术 第七讲 步进电机及其控制(二)

四、步进电机控制电路步进电机控制电路有三种方案:一是采用普通集成电路;二是采用专用集成电路;三是采用微机。 1.采用普通集成电路组成的控制电路①四相步进电机控制电路。四相步进电机的励磁顺序见表2。从励磁顺序我们可以设计分配器电路,一个方向运转的分配器很简单,两个方向运转的稍复杂些。从表2     

光学成像遥感器调焦控制电路仿真测试

提出了一种利用数据采集卡和计算机仿真技术检测和监控光学遥感器调焦控制电路的方法。通过对调焦控制电路的理论分析和实际测量,以数理逻辑、信息技术和系统技术为基础,构造了频率检测、电压检测、编码器反馈的仿真测试数学模型。应用计算机高速信息采集和智能控制技术,设计了调焦控制电路的仿真及测试系统,并进行了实验研究。实验结果表明,该系统能够准确测量工作频率在1.2 kHz以内,控制电压＜40 V的调焦控制电路,完全满足对光学成像遥感器调焦控制电路的仿真及检测要求,并可长时间、方便、高效地监控调焦控制电路的工作运行情况。     

宽电压输入电能表及IC卡控制电路应用研究

本文探讨了一种宽电压输入电能表及IC卡控制电路,其电能表电路包括微控制器、IC卡控制电路、计量电路、显示电路。宽电压输入电能表IC卡控制电路在工作时,将IC卡的到位信号输入到插卡检测电路,插卡检测电路一方面将低电平信号通过主板通讯接口传输到处理器;另一方面将到位信号输入到电源控制电路的控制端,此时电源控制电路工作,给IC卡提供电源。保证了内部电路的可靠运行,减少外部人为破坏的可能性。     

一种避免风机低温失效的解决方案

设计了一种环境温度感知控制电路。当环境温度低于温度控制点时,控制电路断开风机的电源供应,风机停止工作,从而避免风机在低温环境下失效;当环境温度高于温度控制点时,控制电路接通风机的电源供应,风机开始工作,保证设备高温工作的可靠性不受影响。对温度控制点的设定、控制电路的基本原理和具体实现进行了描述。     

信息之窗

由吉林工业大学电焊机研究所研制成功的专用集成电路控制的晶闸管逆变焊机已通过鉴定。此晶闸管逆变焊机ZXT─400Z与国内外同类焊机相比有如下特点：①此焊机将主电路与控制电路共同构成一可控环型振荡系统，在控制电路中无单独脉冲源，这种变频控制法简单可靠。②将控制电路中的主要部分集成在仅有2×3（mm）的专用集成电路芯片上，提高了控制电路抗电磁场干扰的能力。③控制电路的核心是一片专用集成电路，使控制电路大为简化，整个控制电路只有84只元件，安装在140×100（mm）的一块印刷板上。洛阳市孟津传感器制造厂最近研制成功“牙…     

基于单片机控制电路的微波热水器的设计

详细介绍了一种以单片机为核心控制电路的微波热水器,通过对该微波热水器进行控制电路设计和结构设计,可实现漏电、超温和干烧保护等功能。     

气敏传感器测试平台设计

文中设计一套气敏传感器测试平台,该平台包含硬件控制电路和控制软件部分。硬件控制电路可对传感器进行加热,并可测量多个通道传感器电阻阻值,测量结果通过网络上传至控制软件。控制软件包含硬件控制电路参数设置,硬件控制电路校准,实时数据显示以及历史数据回显等功能。测试结果表明:设计的测试平台能满足传感器设计研制阶段的测试需求,硬件控制电路性能稳定,控制软件功能完善,操作简便。     

一种新型的数字式移相电路

脉冲移相控制电路是控硅应用中的关键环节,本文介绍了一种新型的计数式移植相控制电路。     

应用单片微机的蠕动泵控制电路

介绍一种以单片微机为核心的蠕动泵控制电路,这种控制电路具有运行速度、方向、时间可调等多种功能,为提高流动注射分析系统的测量精度和自动化程度创造了有利条件。     

舵机控制电路测试设备硬件设计

本文介绍了一种舵机控制电路的测试设备的硬件设计,分析了系统的总体组成、功能以及特点。阐述了设备与控制电路通信方法、控制信号的切换,以及硬件系统结构和软件设计思路。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.