摩托车制动器试验台电模拟惯量的研究

对电惯量模拟方法进行了深入分析,通过对制动过程中制动力矩的分析,给出了电机在制动器制动时输出的力矩与模拟惯量的关系.采用机械模拟和电模拟相结合的方法设计开发了摩托车制动器试验台,实现制动器台架试验时对当量惯量的模拟.试验表明:采用电惯量模拟后,系统的性能明显优于采用大量飞轮的机械惯量制动器试验台,提高了试验台的自动化程度.     

卡尔曼滤波在摩托车制动器测试系统中的应用

文章采用机械模拟和电模拟相结合的方法设计开发了摩托车制动器测试系统,实现制动器台架试验时对当量惯量的模拟。为了实现对制动器转速系统进行精确控制,设计了PID控制算法,并采用卡尔曼滤波对转速信号进行滤波处理,从而消除了现场随机干扰,抑制了工频干扰。经验证,所设计的制动器测试系统具有很高的测量精度和准确率,并且运行稳定、可靠。     

电惯量模拟机械转动惯量方法的研究

制动器实验台是测试制动器性能和质量的装置。目前,国内外的制动器试验台系统大多采用机械方式：用大型惯量盘的转动惯量来模拟汽车直线运动的动量。本文从制动器实验台系统动力学数学模型和直流电动机原理两个方面分析了电惯量模拟机械转动惯量的实现方法：即按照一定的控制算法控制他励直流电机的电枢回路输入电压,以控制电动机的输出转速,从而实现用电惯量对机械转动惯量的模拟。     

制动器试验台惯量模拟液压实现方法的研究

汽车制动性能直接关系到行车安全,是汽车的主要性能指标之一,它很大程度上取决于制动器性能的好坏。制动器实验台是测试制动器性能和质量的重要装置,对其进行结构精简,使其设计和制造成本降低、检测精度提高,始终是相关研发人员追求的目标。目前,国内外制动器试验台实现形式有机械惯量和电惯量两种,但其各有相应的缺点。为了克服这些缺点,研究了惯量模拟的液压实现方式,分析了其可行性及重要意义,提出了"液惯量"的概念用于制动器试验台的研发。     

风电制动器惯性台架的研制

试验台依据行业国家标准而开发设计,是以机械惯量来模拟风电实际惯量的制动器试验台.为保证试验条件和实际工况的一致性,试验台采用直流电机作为有效风能和负载转速的模拟,采用旋转的惯性飞轮模拟风电机组实际工况中的载荷,利用设计的气压和液压系统模拟风电实际的制动力驱动装置,对风电制动器施加制动力矩.通过对风电制动器各性能参数的检...     

摩托车片式离合器结合过程分析与起步耐久试验台的研究

分析了摩托车离合器的结合过程,建立了摩托车离合器结合过程的数学模型,并在此基础上研究开发了摩托车离合器起步耐久试验台,详细介绍了试验台的工作原理和技术特点.试验台能够进行离合器分离过程试验和起步耐久试验.利用磁粉制动器和惯性轮分别模拟摩托车在坡道上处于满载常用起步档时折算到离合器的坡道阻力矩和当量惯量,进行离合器耐久试验,试验表明,测试系统可靠性高,测量精度高.     

新型摩托车制动器试验台的开发及对标准《摩托车和轻便摩托车制动器台架试验

本文作者在近几年通过努力研制开发成功MZW-31.5型微机控制摩托车制动器综合试验台,在开发及与用户联合实验过程中,发现目前汽车行业标准《摩托车和轻便摩托车制动器台架试验方法》（报批稿）存在一些条款不够完善,故提出以下建议,供业内人士共同探讨。     

新型摩托车制动器试验台的开发及对标准《摩托车和轻便摩托车制动器台架试验方法》的几点建议

本文作者在近几年通过努力研制开发成功MZW-31.5型微机控制摩托车制动器综合试验台,在开发及与用户联合实验过程中,发现目前汽车行业标准《摩托车和轻便摩托车制动器台架试验方法》(报批稿)存在一些条款不够完善,故提出以下建议,供业内人士共同探讨。     

摩托车制动器综合性能测试系统的研究

分析了传统惯性飞轮的制动器实验台的特点,给出了电模拟和机电混合模拟制动器台架的设计方法,并在此基础上开发出了摩托车制动器综合性能测试系统,满足50-250ml系列摩托车鼓式和盘式制动器台架试验的要求。     

摩托车片式离合器性能综合测试系统

开发了摩托车片式离合器综合测试系统,详细介绍了测试系统的工作原理和技术特点.测试系统采用2台变频电机分别驱动,能够进行静摩擦力矩测量、动摩擦力矩测量,以及离合器分离过程试验, 提出了一种离合器的轴向压紧力的测量方法.利用磁粉制动器和惯性轮,分别模拟摩托车在4°35′坡道上、处于满载常用起步档时折算到离合器的坡道阻力矩和当量惯量,进行离合器耐久试验,试验表明,测试系统可靠性高,测量精度高.     

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.     

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....     

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。     

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.