排序方式: 共有53条查询结果,搜索用时 656 毫秒
21.
22.
跨座式单轨作为中等规模城市轨道交通模式的适应性分析 总被引:3,自引:0,他引:3
为能给中等规模城市选择一种经济适用环保高效的轨道交通系统制式,通过分析我国的城市结构特征、轨道交通发展政策和现状,进而说明我国中等规模城市对轨道交通的需求具有中低运量系统需求大、对投资建设及运营经济性、环保性和运营效率安全要求高等特征,通过分析轮轨轻轨制式钢轮钢轨(高架B型车、C型车)、(跨座式)单轨、直线电机、胶轮导轨和中低速磁浮等系统对需求特征的适应性,并进行综合技术经济指标对比,指出跨座式单轨应成为轻轨(中运量)系统的主导模式,最后对如何促进跨座式单轨的发展提出了合理建议。 相似文献
23.
针对传统机器人滚边仿真设计软件功能不完善,现场机器人调试需要对机器人路径做较大更改,以致精度不高的问题,对机器人滚边仿真做了系统研究。以车身门盖上的机器人前盖滚边工位为例,应用西门子Robcad软件,对机器人滚边方案进行了规划,完成了滚边工位的机器人仿真,验证了方案的可行性。同时,应用Robcad的OLP(Off-Line Program)功能导出滚边离线程序,并将程序下载到现场机器人进行修正后直接用于调试,修正后的效果达到了设计要求,通过多个项目已证明了此方法的实用性和可靠性。并对该仿真技术进行了总结和展望。 相似文献
24.
25.
26.
在城市道路"十"字路口路段,互通式环形立交异形板多有应用。环形立交异形板结构受力非常复杂,较难通过手算解决工程应用问题。通过对某桥环形立交异形现浇板进行有限元建模分析及工程应用,可为此类工程结构分析及应用提供参考。 相似文献
27.
可控式被动减摇水舱最佳相位PD控制策略研究 总被引:1,自引:1,他引:0
在"船舶-可控式被动减摇水舱"系统数学模型的基础上,综合船舶横摇运动信息设计最佳相位PD控制器,并对可控式被动减摇水舱气阀的开启和关闭进行控制。在不规则波下的仿真结果表明,与常规控制相比,采用最佳相位PD控制策略能够取得更好的减摇效果,最大程度上发挥可控式被动减摇水舱的减摇能力。 相似文献
28.
稀浆封层修复水泥混凝土路面的探讨 总被引:1,自引:0,他引:1
李农 《筑路机械与施工机械化》2004,21(6):29-30
分析了应用乳化沥青稀浆封层修复水泥混凝土路面应该注意的几个问题,提供了一种新的将刚性路面改为柔性路面、提高路面抗滑性和平整度以及降低渗水率和噪声值的维修养护工艺和方法. 相似文献
29.
30.
Nong Zhang Guang-Ming Dong Hai-Ping Du 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2008,46(4):271-293
Vehicle rollovers may occur under steering-only maneuvers because of roll or yaw instability. In this paper, the modified fishhook and the sine maneuvers are used to investigate a vehicle's rollover resistance capability through simulation. A 9-degrees of freedom (DOF) vehicle model is first developed for the investigation. The vehicle model includes the roll, yaw, pitch, and bounce modes and passive independent suspensions. It is verified with the existing 3-DOF roll-yaw model. A rollover critical factor (RCF) quantifying a vehicle's rollover resistance capability is then constructed based on the static stability factor (SSF) and taking into account the influence of other key dynamic factors.
Simulation results show that the vehicle with certain parameters will rollover during the fishhook maneuver because of roll instability; however, the vehicle with increased suspension stiffness, which does not rollover during the fishhook maneuver, may exceed its rollover resistance limit because of yaw instability during the sine maneuver. Typically, rollover in the sine maneuver happens after several cycles.
It has been found that the proposed RCF well quantifies the rollover resistance capability of a vehicle for the two specified maneuvers. In general, the larger the RCF, the more kinetically stable is a vehicle. A vehicle becomes unstable when its RCF is less than zero. Detailed discussion on the effects of key vehicle system parameters and drive conditions on the RCF in the fishhook and the sine maneuver is presented in Part II of this study. 相似文献
Simulation results show that the vehicle with certain parameters will rollover during the fishhook maneuver because of roll instability; however, the vehicle with increased suspension stiffness, which does not rollover during the fishhook maneuver, may exceed its rollover resistance limit because of yaw instability during the sine maneuver. Typically, rollover in the sine maneuver happens after several cycles.
It has been found that the proposed RCF well quantifies the rollover resistance capability of a vehicle for the two specified maneuvers. In general, the larger the RCF, the more kinetically stable is a vehicle. A vehicle becomes unstable when its RCF is less than zero. Detailed discussion on the effects of key vehicle system parameters and drive conditions on the RCF in the fishhook and the sine maneuver is presented in Part II of this study. 相似文献