基于Matlab的电动汽车ABS仿真分析

随着电动汽车产业的发展,电动汽车保有量迅速增加,电动汽车的行驶安全变得越来越重要。以电动汽车制动系统为研究对象,分析了传统制动系统和装有防抱死制动系统(ABS)车辆制动时参数的变化规律,建立了制动系统的数学模型,利用Simulink对传统制动系统进行了仿真,同时对釆用PID控制策略的防抱死制动系统进行了仿真分析。通过仿真得到了制动时车速、轮速、滑移率、制动距离随时间的变化曲线,通过对比发现装有ABS的制动系统在紧急制动时可以有效縮短制动距离,提高汽车制动过程中的操纵稳定性。     

基于Simulink的汽车ABS仿真分析

针对汽车在有无ABS情况下制动能否保证良好的稳定和制动性的问题,对汽车整个ABS系统模型进行了仿真研究。对单轮车辆模型进行了动力学分析,得出了其车辆动力学数学公式,然后利用Simulink搭建了单轮车辆模型的数学仿真模型;依次分析了基于魔术公式的汽车轮胎模型、制动系统模型、滑移率模型以及PID控制模型的数学公式,搭建了相关仿真模型;最后将各个模块组合成了一个完整的汽车ABS仿真模型,并对有无ABS下的汽车制动工况进行了对比。研究结果表明:所建立的ABS系统模型可靠,在制动过程中具有良好的稳定和制动性。     

基于路面识别的汽车ABS模糊控制仿真

汽车防抱制动系统（ABS）通过在制动过程中自动控制车轮的制动力矩,从而防止了车轮抱死。为了进一步提高汽车ABS的性能,在对汽车制动过程进行动力学分析的基础上,建立了ABS系统的模糊控制模型;采用路面识别方法,对变附着系数路面进行了ABS制动模拟仿真。仿真结果表明,基于路面识别的模糊控制防抱制动系统能取得较好的控制效果,并具有一定的自适应能力。     

基于动力学模型的车辆防抱死制动系统仿真

将系统动力学与智能控制理论相结合对汽车制动防抱死控制系统进行了研究,利用matlab/Stateflow仿真技术,建立了基于七相位逻辑门限值控制算法的ABS仿真程序,建立了包括车身模型、轮胎模型、制动系统模型在内的七自由度的车辆动力学模型,准确地表达了车辆的动态特性。在实验中以捷达GTX轿车的车辆参数为模型,对其在高附着路面下不同车速的防抱死制动过程进行了仿真,并通过仿真的实验的结果来改变逻辑门限值的选取,进而完善ABS控制算法。该仿真系统的车辆模型参数在经过修改后可适用于不同ABS产品的开发并对ABS与目标车辆的匹配提供了依据。     

汽车ABS模糊PID控制方法的仿真研究

以防抱死制动系统(ABS)滑移率为对象进行控制,根据ABS系统原理建立了ABS单车轮的仿真模型,并对基于滑移率的PID参数模糊自整定控制的汽车ABS系统进行了仿真与研究,仿真结果证明,把PID参数模糊自整定控制应用在ABS系统中能达到较好的控制效果.     

基于MATLAB下的制动系统建模、仿真及ABS控制器设计

本文对某汽车ABS制动系统进行仿真建模,并对其进行单轮模型和分段线性的轮胎模型的建立;在Matlab环境下对ABS控制器进行设计和仿真分析;提出了一种门限值控制算法,对制动液压控制系统实现增压、保压、减压动作,使得汽车制动时的滑移率控制在一定范围内,以保证汽车的平稳制动.得出ABS控制下的滑移率时域结果图、车轮前进速度...     

车辆弯道制动防抱死系统仿真

基于Matlab/Simulink仿真技术,充分考虑车辆弯道制动时因为纵向和侧向加速度的存在而引起轮胎所受垂直载荷的变化,建立了汽车弯道行驶的八自由度整车动力学仿真模型,嵌入了ABS控制逻辑模型。对弯道制动工况下的车速、横摆角速度、转弯半径以及车轮滑移率的变化进行了仿真计算,结果表明该模型可以全面准确的模拟车辆在弯道制动时的运动状况,为开发和改进ABS系统提供了很好的参考依据。     

计算机仿真技术在汽车ABS系统性能分析中的应用

利用MATLAB／SIMULINK仿真软件,对汽车ABS系统性能进行了仿真研究,经过计算、推导,建立了适合汽车ABS系统的4个重要模型,即整车模型、制动器模型、轮胎模型、控制器模型。应用MATLAB／SIMUuNK软件建立了ABS系统制动性能仿真模型,同时对车轮加减速度门限值的控制方法进行了仿真研究分析,仿真结果表明,采用P1R4控制逻辑,能较好地利用路面的附着性能,提高汽车制动效果。     

基于Matlab/Simulink的电子感应汽车制动系统控制规则的研究与仿真

本文利用MATLAB/SIMULINK软件建立单轮车辆的电子感应汽车制动系统仿真模型及普通ABS的仿真模型,研究模糊控制规则,比较分析两者的仿真情况,结果显示电子感应汽车制动系统制动性能优于普通ABS.     

基于路面识别的汽车ABS滑模控制方法的研究

为了提高汽车的制动效能和行驶安全性,针对目前常用的汽车ABS控制方法,在没有考虑道路状况变化对汽车滑移率及减速度等参量变化的影响而容易引起汽车侧滑、甩尾等不良状况,提出了基于路面识别的汽车ABS滑模控制方法,该方法根据制动过程中的汽车滑移率及减速度来进行路面识别,动态地获取汽车最佳滑移率,并以此对汽车ABS进行滑模控制;然后以单轮整车制动模型为对象,利用MATLAB/Simulink软件对该控制方法进行计算机仿真实验分析;结果表明,与常用的汽车ABS逻辑门限值及无路面识别的滑模控制方法相比,该方法可以使汽车制动时间减少5%～12%,从而使汽车制动效能和行驶安全性得以提高。     

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.     

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.