双横臂悬架导向机构杆长配置对车轮外倾角的影响

基于双横臂悬架结构及运动学分析,推导出机构几何参数与车轮外倾角的数学表达式。利用MATLAB软件进行仿真计算,获得了车轮外倾角变化曲线形态与杆长配置的相互关系和规律,得到较为理想的双横臂悬架布置方案。从而为设计具有合理外倾角变化的双横臂悬架导向机构提供借鉴。     

基于ADAMS的某型越野车悬架仿真与优化研究

以ADAMS/Car车辆动力学仿真软件为基础,根据双横臂独立悬架关键硬点坐标,建立某型越野车双横臂式独立前悬架动力学模型,并对前悬架系统进行车轮跳动仿真。在ADAMS/Insight中对前悬架定位参数进行灵敏度分析。根据前轮定位参数的变化规律和灵敏度分析结果,选取悬架的8个关键硬点坐标为设计变量,对4个悬架定位参数进行优化设计。仿真结果表明,优化后的双横臂独立悬架的运动学特性得到改善。     

基于ADAMS/VIEW的双横臂式独立悬架转向梯形机构断开点位置的仿真分析

通过建立某轻型卡车双横臂式独立悬架的数学模型和仿真模型,利用ADAMS软件仿真汽车运动过程中不同断开点位置车轮前束角的变化规律,并用空间解析几何关系式验证了仿真结果的正确性与可靠性.与其它方法相比,本方法更具有直观性,计算结果更加符合实际情况,为双横臂独立悬架转向梯形机构设计提供了较为精确的实用方法.     

双横臂独立悬架导向机构硬点匹配设计

介绍了根据整车参数,在满足悬架性能的基础上,匹配设计悬架导向机构硬点的方法.以国内一款正在研发的电动小车为例,计算了与小车相匹配的双横臂独立悬架导向机构硬点位置坐标,在ADAMS/CAR下建立了小车悬架模型,仿真结果表明初次匹配的悬架导向机构基本合理;并通过ADAMS/INSIGHT,对悬架定位参数的影响因子进行了分析,重新匹配计算了硬点坐标,仿真验证重新匹配的机构更能满足设计要求.研究结果为悬架设计的研究提供了参考.     

ADAMS/Car与Insight在双横臂悬架优化设计中的应用

运用ADAMS/Car初步建立了某特种车的双横臂式前悬架,并通过双轮平行跳动仿真分析了轮跳对前轮定位参数的影响,选出需要优化的参数。通过ADAMS/Insight对悬架硬点进行灵敏度分析,找到影响性能较大的硬点坐标。对于灵敏度较大的设计参数建立车轮定位参数在轮跳过程中最大变化量的二阶响应面近似数学模型,利用MATLAB编程拟合出近似模型并进行优化求解与可靠性分析。修改优化后的悬架硬点坐标再次进行仿真试验比较优化前后的试验结果,验证优化的合理性。     

全地形消防车双横臂悬架仿真分析与优化

以悬架设计理论为基础,设计了全地形消防车双横臂悬架。通过SolidWorks建立全地形消防车悬架模型,以建立的双横臂悬架三维模型和设计参数,利用ADAMS/Car建立全地形消防车双横臂悬架动力学虚拟样机模型。之后对双横臂悬架虚拟样机模型进行双轮平行跳动仿真试验,分析各定位参数变化后得出主销内倾角变化范围不合理。之后联合ADAMS/Insight对悬架硬点进行灵敏度分析及优化。结果表明优化后的主销内倾角达到了合理变化范围,其他定位参数也均有了一定的改善,有效的提升全地形消防车悬架性能。     

全方位线控四轮转向电动汽车设计

提出了一种用于外转子式轮毂电机的双横臂悬架导向机构和转向机构，可实现四轮驱动电动汽车绕任一点进行旋转，以及沿任一方向进行平移。研究了当电机失灵时的故障排除技术，即可通过电磁离合器的开关组合，驱动一台转向电机可使四个车轮全部复位，且仍可保持转向能力。用Euler角描述了悬架导向机构的姿态，推导出与车轮定位参数相关的悬架导向机构姿态角公式，对各控制点坐标进行参数化，在ADAMS软件下建立了参数化模型，并对悬架导向机构进行了优化设计。     

FSAE赛车前轮定位参数的优化研究

针对大学生方程式(FSAE)赛车前轮定位参数的优化设计问题,基于ADAMS/Car模块建立FSAE赛车双横臂独立悬架的仿真模型,对前轮定位参数进行仿真分析。利用ADAMS/Insight模块进行优化设计,确定设计参变量和设计目标,对所选定的设计目标进行影响因素分析;根据优化结果修改前悬架仿真模型,再次进行前轮定位参数的仿真分析。结果表明:赛车车轮上下跳动时,优化后的前轮定位参数能够在合理的范围内变化,满足赛车悬架设计要求,赛车悬架的主要性能得到明显提高。     

利用ADAMS/car对双横臂悬架的动态仿真与分析

利用ADAMS/car软件对样车建立双横臂悬架仿真模型,并对后倾拖距、磨胎半径、侧倾中心、四个定位角和车轮跳动量进行动态仿真。通过对仿真结果与样车悬架相应参数进行比较,验证了仿真模型的动特性与样车悬架动特性的一致性。其结论对汽车悬架的设计与开发具有一定的参考价值。     

基于遗传算法的悬架硬点运动学的优化

为了准确分析悬架的运动学特性,利用Matlab建立了双横臂悬架运动学仿真数学模型,利用CAT-IA/DMU验证了数学模型的准确性,通过该模型分析了轮胎跳动对车轮定位参数的影响,并通过遗传算法对悬架的硬点进行优化,结果表明:优化后的悬架运动特性得到了改善。     

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.