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为获得虚拟场景中车辆真实物理运动和交互性,提出一种基于开放式动力学引擎(ODE)的虚拟仿真平台集成方案.构建具有四自由度的汽车刚体动力学简化模型,分析其ODE特性及刚体连接机理,对车身和车轮之间的悬架系统进行分析,采用ODE中Hinge2进行模拟,分析其刚体动力学方程;基于Quest3D和VS2005进行刚体碰撞检测算法研究,构建一个能实现车辆刚体运动和碰撞检测的虚拟仿真平台,实时对车辆刚体动力学相关参数进行输出.经验证,该虚拟仿真系统具有良好的沉浸感、交互性和实用性. 相似文献
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无人飞行器控制系统实验课程体系研究 总被引:1,自引:0,他引:1
阐述了无人飞行器控制系统实验课程的教学特点,分析了无人飞行器控制系统实验课程体系建设的原则,提出了一种经过教学实践检验的无人飞行器控制系统实验教学体系,进行了相应教学实验装置的开发,该试验装置能够在组件级、系统级和试验评估级三个层次上组织实验,可显著提高飞行器控制系统实验教学质量。 相似文献
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李为民 《内蒙古大学学报(人文社会科学版)》2011,43(1):56-60
当代大学组织价值定位面临的困境缘于理想与现实之间多样化的矛盾冲突。分析大学组织价值定位的特征,应考察其历史演进的过程,选择连续动态的视角。大学组织价值定位具有内外互动、动态变化、内在冲突、非均衡化的特征。当代大学组织并不存在最优化和普适性的价值模式,应按照权变思想,从现实条件出发确定符合自身实际的价值定位。 相似文献
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The wheel-rail relationship in turnout is more complicated than that in ordinary track. Profile wear and machining errors of the wheelset cause deviations of the rolling radius on different wheels. Therefore, wheelsets move to the direction of smaller diameter wheels in search of a new stable state and to change the condition before entering the turnout. The main aim of the present work is to examine the wheel-turnout rail dynamic interaction combined with the static contact behaviour. Calculations are performed on a high-speed vehicle CRH2 and the No. 12 turnout of the passenger dedicated line. The wheel-turnout contact geometric relationship and normal contact behaviour under wheel diameter difference are assessed by the trace principle and finite element method. A high-speed vehicle-turnout coupling dynamic model is established based on SIMPACK software to analyse the wheel-rail dynamic interaction, riding comfort, and wear. Both the wheel diameter amplitudes and distribution patterns are accounted for. The simulation shows that wheel diameter difference can greatly disturb the positions’ variation of wheel-rail contact points and affect the normal contact behaviour on switch rails by changing the load transition position. The effect of wheel diameter difference on wheel-turnout rail dynamic interaction can be divided into three according to its amplitude: when the wheel diameter difference is within 0–1.5 mm, the wheel flange comes into contact with the switch rail in advance, causing a rapidly increased lateral wheel-rail force; when it is within 1.5–2.5 mm, trains are subject to instability under equivalent in-phase wheel diameter difference; when it is larger than 2.5 mm, the continuous flange-switch rail contact helps strengthen the vehicle stability, but increases the wheel-rail wear. It is recommended to control the wheel diameter difference to within 2.5 mm but limit it to 2 mm if it is distributed in-phase. 相似文献
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在磁浮列车运行时,需要调节空气弹簧的刚度来保证车体的平稳,本文设计了一种基于现场可编程逻辑门阵列(FPGA)信号处理的、以继电器为主要控制器件的磁浮列车空气弹簧充排气控制模块来调节空气弹簧的刚度.试验证明该设计是可行的,能够满足磁浮列车空气弹簧控制系统的要求. 相似文献
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为了研究高压架空输电线索结构与塔架等其他杆件连接处的滑移特性,定义了一组滑移索单元,由一个通过滑动节点连接的三节点活动滑移索单元和多个两节点非活动滑移索单元组成.基于更新拉格朗日格式推导了三节点直线型滑索单元几何非线性刚度矩阵,并通过两跨和三跨等高连续索结构的有限元数值算例验证了空间直线型滑移索单元的有效性.研究结果表明,推导的直线型滑移索单元张力与已有计算结果相比,误差在1%以内.考虑滑移的索结构初始平衡状态内力与不考虑滑移的情况比较相差较大,因而在实际工程中应该考虑索的滑移. 相似文献
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介绍了磁浮列车悬浮系统及其平衡点附近线性化模型,针对模型的非线性问题,利用反馈线性化技术,建立了电流控制输入下的输入-状态线性化模型;利用MATLAB软件建立了两种线性化方法的仿真模型,仿真并通过比较分析,表明反馈线性化技术是解决磁浮列车非线性模型的控制问题的一个有效途径。 相似文献
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由于城市交通信号灯控制存在着非线性动态特性,对其进行控制时很难进行精确的数学建模,同时路口交通流具有重复性特点,呈现明显的周期性特征。为了减少路口车辆等待时间、提高通行效率,利用迭代学习控制方法,对信号灯周期和各个相位有效绿灯时间进行优化,从而对路口绿灯进行最大化利用,保证车辆在路网中能够高效、平稳地通行。仿真结果表明,在迭代次数达到 15 次之后,排队长度相位差和误差都趋于零,减少了交通拥堵时间。 相似文献
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欧智菁俞杰林上顺王金泽 《福建工程学院学报》2019,(6):511-517
以黄桷湾特大桥为工程背景,选取轴压比、梁墩刚度比、系梁布置形式及柱肢混凝土强度等级为设计参数,应用Midas Civil有限元软件构造了20座三跨对称桥梁计算模型。研究E1地震作用下钢管混凝土双肢格构墩连续梁桥主要控制截面参数地震响应,探讨各设计参数对钢管混凝土双肢格构墩连续梁桥抗震性能的影响规律,并对全桥进行优化验证。研究结果表明:轴压比对地震作用下结构内力和位移有一定影响,建议控制在0.15~0.25;梁墩刚度比对结构的抗震性能影响较大,控制在4.08~10.90时结构的内力分布更加合理;核心混凝土的强度在C40~C50时取值较为合理。 相似文献
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钢-混凝土组合箱梁日照温差的实测和理论分析(英文) 总被引:2,自引:0,他引:2
为了探讨和验证钢-混凝土组合截面日照温度场的计算方法, 依托某大跨径三跨变截面连续箱梁桥, 对钢-混凝土组合箱梁的日照温度场进行了现场实测. 通过实测发现, 由于各腹板接受太阳漫散射的程度不同, 外侧钢梁温度普遍高于内侧箱梁, 且钢箱的整体平均温度数值与箱内空气基本吻合. 在此基础上借助ANSYS有限元计算软件, 根据不同位置钢腹板所处环境条件确定了各自的太阳辐射和对流换热情况, 进行了综合边界条件的瞬态热分析. 各测点理论计算结果与实测数据能较好地吻合, 温度差值在2℃以内, 说明了理论计算方法的可靠性, 为后续深入研究钢-混凝土组合截面日照温度场奠定了基础. 相似文献
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引入二次多项式平方轮胎模型,选取合适的状态变量,建立了四轮转向汽车四维非线性动力学系统,应用中心流形定理对其进行了降维处理并转换为中心流形上的一阶约化系统.应用非线性分岔和稳定性理论对均匀路面工况的稳定性进行了分析,并在Matlab/Simulink中进行了仿真.结果表明:随着车速和前轮转角的增加,高维四轮转向汽车奇异点处会发生鞍结分岔,该分岔会导致汽车失稳. 相似文献
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针对干冰清洗车的工作特点,引入电液比例控制技术来控制马达卷扬升降装置,进而控制清洗喷射装置的运行速度.然后对比例控制系统建模,借助Matlab/Simulink软件对系统模型进行动态特性仿真与分析,并对马达卷扬系统进行传统PID控制器与模糊控制器建模与仿真.仿真结果得出模糊控制具有响应速度快、鲁棒性好、控制精度更高等优点. 相似文献
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The response of dynamic wave pressures on structures would be more complicated and bring about new phenomena under the dynamic interaction between soil asnd structure.In order to better understand the response characteristics on deeply embedded large cylindrical structures under random waves,and accordingly to offer valuable findings for engineering ,the authors designed wave flume experiments to investigate comparatively dynamic wave pressures on a single and on continuous cylinders with two different cembedment depths in response to two wave spectra ,The time histories of the water surface elevation and the corresponding dynamic wave pressures exerted on the cylinder were analyzed in the frequency domain,By calculating the transfer function and spectral density for dynamic wave pressures along the height and around the circumference of the cylinder,experimental results of the single cylinder were compared with the theoretical results based on the linear diffraction theory ,and detailed comparisons were also carried out between the single and continuous cylinders ,Some new findings and the corresponding analysis are reported in present paoer,The investigation on continuous cylinders will be used in particular for reference in engineering applications becaus information is scarce on studying such kind of problem both analytically and experimentally. 相似文献
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INTRODUCTIONServo pneumaticsystemshavebeenstudiedsincethe 1 950’s.Duetotheirnaturalcharacter isticsofaircompressibility ,poordampingabili ty ,significantmechanicalfriction ,andstrongnonlinearities,theirapplicationwasrestricted .Withtherapiddevelopmentinthefie… 相似文献