单片机系统中怎样实现步进电机的变速和位移

步进电机能接受步进脉冲的控制一步一步地旋转。随着单片机的推广，步进电机成了微计算机应用项目的主要执行元件之一。尤其在精确定位场合中得到了广泛的应用。本文介绍用单片机控制步进电机的变速和位移。     

步进电机在控制发动机油泵调节器油门开度中的研究与应用

本文研究和分析了步进电机控制某航空发动机油泵调节器油门开度的机理,提出了一种步进电机应用于控制油门开度大小的控制方案,设计了步进电机控制油泵调节器油门开度的机械传动装置,实现了对步进电机的计算机控制。通过对该控制系统的试验,表明：本文设计的控制系统不仅结构简单,能有效地实现对某航空发动机油泵调节器油门开度的控制,而且控制的精度较高。     

振动攻丝机的控制系统

振动攻丝是一种新型的加工方法。本系统用步进电机作为动力源实现丝锥的扭转振动,简化了机械结构。本文介绍了各子系统的功用及控制方法。步进电机及其驱动系统将脉冲信号放大去控制步进电机的运行。微型计算机控制系统控制脉冲序列的发送,实现振动攻丝中转速、振幅和频率的无级调整。切削过程控制系统利用测力传感器取得信号,经过A/D转换和数据处理,再将数字信号反馈给计算机去控制攻丝参数的改变。     

基于PIC的步进电机细分控制器

为了实现永磁式步进电机的细分控制,采用PIC18F2331单片机作为主控单元接收外部的脉宽调制（PWM）步进电机控制信号,并辅之以外部功率驱动电路完成了步进电机细分控制器的硬件设计,并应用C语言编写了相应的PWM信号至步进电机控制信号的转换程序,实现了对2／4相步进电机的开环细分控制。此外,还利用单片机的串行通信模块,设计了与计算机的串行通信电路,方便了系统的调试和监控。测试结果表明,该控制器能实现对步进电机的细分控制。     

混合式步进电机细分控制方法优化策略研究与仿真

针对混合式步进电机闭环控制系统的固有缺点、数学参考模型的失真、电机磁滞损耗和涡流损耗的问题,结合混合式步进电机结构原理、步进电机细分控制原理、最优控制思想和自适应控制思想,分别将最优性能指标、直接电流反馈以及有限时间参考模型修正方法引入到步进电机受控系统中。在三相混合式步进电机的数学模型基础上,分别采用普通细分控制方法和基于优化思想的细分控制方法进行了Simulink仿真。研究结果表明,采用基于优化思想的细分控制方法,可以较好地提高电机的控制性能。     

机器人步进电机的最优机械控制数据建模与仿真

步进电机的控制精度会对电机位移和数字脉冲产生影响,为了提高步进电机最优机械控制数据的准确性,确保步进电机最优机械控制效果,提出机器人步进电机的最优机械控制数据建模与仿真方法。该方法优先分析了机器人步进电机的内部结构、工作原理,并利用数学模型推导出传递函数,以此达到简化步进电机的目的。基于分析结果建立控制模型,实现最优控制机器人步进电机,并依据仿真分析结果验证最终控制效果。实验结果表明,所提方法的机器人步进电机最优机械控制效果较好,能够有效提高机器人步进电机最优机械控制精度。     

基于AT89S51单片机的步进电机控制系统的研究

介绍了以AT89S51单片机为核心的步进电机控制系统;在讨论了步进电机工作原理基础上,提出步进电机控制中硬件和软件的注意点和解决方法。     

具有止动点的步进电机控制设计

通常对步进电机的驱动控制是采用开环控制的,但是当步进电机工作在具有运行的止动点时,步进电机就需要根据当前的状态自动调节自身的运行速度。为了实现对具有止动点步进电机的自动控制,采用了一种通过角度反馈实现步进电机控制的方法,可以使步进电机自动寻找最小最大止动点,并且可以在运行接近止动点时实现缓慢可靠的停止。     

基于PLC的KTV自助机器人控制系统的研究

自助机器人的动作是由步进电机来驱动,步进电机的控制精度比较高,在工业上有着广泛的应用。介绍步进电机的控制机理和使用PLC对步进电机控制的具体过程,给出了控制系统的硬件、软件设计方法。实际使用效果明显。     

步进电机多轴联动DSP控制系统研究

本文论述了用数字信号处理器DSP实现步进电机多轴联动的控制方法。介绍步进电机的驱动控制和DSP的PWM脉宽调制原理,详细阐述了DSP实现步进电机的加减速控制问题。实验表明用DSP实现步进电机的多轴联动控制比较简单且灵活。     

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.