MATLAB在运动控制系统实验教学中的应用

为了加深学生对《运动控制系统》这门课程的理解并提高教学效果,将MATLAB的Simulink及SimPowerSystems电力系统工具箱引入运动控制系统课程实验教学中,以转速、电流双闭环直流调速系统为例,利用MATLAB分别建立了直流V-M系统及直流PWM系统仿真模型.实践证明,通过更新教学方法、加强实验环节,学生能...     

三峡水库135～139m蓄水阶段万州—李渡河段床沙粒径变化特性

从2003年6月-2006年9月三峡水库库水位按135 ～ 139 m方式运行(枯水期坝前水位139 m,汛期坝前水位135 m),其回水末端位于涪陵李渡附近,常年库区在丰都以下.分析了该阶段蓄水期三峡库区原型观测资料,研究了万州(—)涪陵李渡河段床沙沿程变化特性及淤积物的级配组成,由该河段的床沙粒径变化分析其泥沙基本...     

轿车车门的模态计算和组合式优化分析

以模态分析理论为基础,通过有限元软件HyperWorks对车门进行了模态分析,考察了该车门的刚度特性;并用拓扑优化中的变密度法,通过HyperWorks对轿车车门进行了拓扑与形貌的组合分析,得到了高刚度、轻质量的设计方案.     

Mesoscale subduction at the Almeria–Oran front: Part 1: Ageostrophic flow

This paper presents a detailed diagnostic analysis of hydrographic and current meter data from three, rapidly repeated, fine-scale surveys of the Almeria–Oran front. Instability of the frontal boundary, between surface waters of Atlantic and Mediterranean origin, is shown to provide a mechanism for significant heat transfer from the surface layers to the deep ocean in winter. The data were collected during the second observational phase of the EU funded OMEGA project on RRS Discovery cruise 224 during December 1996. High resolution hydrographic measurements using the towed undulating CTD vehicle, SeaSoar, traced the subduction of Mediterranean Surface Water across the Almeria–Oran front. This subduction is shown to result from a significant baroclinic component to the instability of the frontal jet. The Q-vector formulation of the omega equation is combined with a scale analysis to quantitatively diagnose vertical transport resulting from mesoscale ageostrophic circulation. The analyses are presented and discussed in the presence of satellite and airborne remotely sensed data; which provide the basis for a thorough and novel approach to the determination of observational error.     

运动可逆式引信安全系统逻辑控制分析

针对传统引信安全与待发状态控制的不可逆问题,提出了一种运动可逆式引信安全系统。这种安全系统在解除保险和隔爆后利用遥控装置发出的指令信息完成恢复保险及隔爆,具有较高的安全性和可靠性。分析结果表明：运动可逆式安全系统能实现＂安全的人工失效＂,其安全性要远高于传统不可逆式安全系统;可对机构工作过程多次检测和故障定位。适用于低发射过载的高价值弹药引信。     

交通流特征深度认知的车队运行参数优化方法

为提升车队对周围交通流环境的认知能力，获取车队周围多车的运行模式，同时通过改变车队运行参数实现车队群体对周围多车群体运行模式的诱导变化，为提升车队及交通流整体运行效率提供优化策略，提出了基于狄利克雷混和高斯过程的车队周围多车运行模式获取算法，将车队周围多车车辆的复杂运行模式视为混和高斯过程，利用狄利克雷分布作为高斯混和权重的先验分布，建立车队周围多车运行模式速度场，从而获取车队周围多车运行模式并分类；通过比较不同多车运行模式下车队的运行效率，提升车队对所处运行环境的认知能力。研究结果表明：利用非参数贝叶斯算法将复杂的多车运行状态进行分类，获取的车队周围多车运行模式可表现为对车队运行效率产生不同影响的速度场；通过将车队周围的多车运行仿真数据分成多个运行模式，可获取不同多车运行模式下车队及交通流整体运行特性；通过更改车队运行参数，观察不同多车运行模式的占比变化，可获取车队运行参数对所处运行环境改变的影响趋势；车队周围多车运行模式的获取，不仅可以提升车队对周围运行环境的认知能力，使得车队能够选取有利路径行驶，同时能够为车队运行策略的优化提供有效的信息。     

摆动式转向架技术的创新与发展

介绍了摆动式转向架的基本原理,阐述了摆动式转向架技术在中国的创新与发展,总结了摆动式转向架在中国的推广应用情况。     

Influence of uneven rail irregularities on the dynamic response of the railway track using a three-dimensional model of the vehicle–track system

A mathematical model of the vehicle–track interaction is developed to investigate the coupled behaviour of vehicle–track system, in the presence of uneven irregularities at left/right rails. The railway vehicle is simplified as a 3D multi-rigid-body model, and the track is treated as the two parallel beams on a layered discrete support system. Besides the car-body, the bogies and the wheel sets, the sleepers are assumed to have roll degree of freedom, in order to simulate the in-plane rotation of the components. The wheel–rail interface is treated using a nonlinear Hertzian contact model, coupling the mathematical equations of the vehicle–track systems. The dynamic interaction of the entire system is numerically studied in time domain, employing Newmark's integration method. The track irregularity spectra of both the left/right rails are taken into account, as the inputs of dynamic excitations. The dynamic responses of the track system induced by such irregularities are obtained, particularly in terms of the vertical (bounce) and roll displacements. The numerical model of the present research is validated using several benchmark models reported in the literature, for both the smooth and unsmooth track conditions. Four sample profiles of the measured rail irregularities are considered as the case studies of excitation sources, examining their influences on the dynamic behaviour of the coupled system. The results of numerical simulations demonstrate that the motion of track system is significantly influenced by the presence of uneven irregularities in left/right rails. Dynamic response of the sleepers in the roll direction becomes more sensitive to the rail irregularities, as the unevenness severity of the parallel profiles (quantitative difference between left and right rail spectra) is increased. The severe geometric deformation of the track in the bounce–pitch–roll directions is mainly related to such profile unevenness (cross-level) in left/right rails.     

机器人用高精度RV减速机几何回差分析

分析并建立了机器人用高精度ＲＶ减速机几何回差计算的数学模型。并通过计算机模拟与生产实践予以验证。     

上海地铁车辆的临修技术[2]——车辆空调及客室车门的临修

介绍了地铁车辆空调的一般故障及临修方法,并分析了车辆移动门与塞拉门的特点,对其故障与临修技术进行了说明。