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排序方式: 共有377条查询结果,搜索用时 15 毫秒
321.
对港口装卸搬运车辆曲柄滑块式转向机构进行技术分析,给出常用的内置式前桥转向机构和外置式后桥转向机构的运动学分析模型,通过图解法、解析法和ADMAS运动学分析对曲柄滑块转向机构进行深入的研究,并列举了包括原始数据和优化结果的计算实例。 相似文献
322.
散装货船装卸过程的潜在危险 总被引:1,自引:0,他引:1
[摘 要]以散装货船装卸货的特殊性为出发点,介绍了散装货船在装卸货物过程中可能存在的潜在危险及防范措施,旨在保证散装货船装卸过程中的安全。 相似文献
323.
以天津港为例,结合国内各大港口实际情况,对目前港口装卸工属具的使用管理存在的问题进行了分析,提出建设港口工属具管理中心的构想,并对其实施方案和效益进行了初步分析。 相似文献
324.
ZPMC近年来研制了多种新型散货机械,包括既可卸集装箱又能用抓斗作业的多功能卸船机、适用于20万t散货船的4 500 t/h装船机、3 000 t/h斗轮堆取料机以及三翻翻车机等,这些机型技术先进,结构上越来越完善. 相似文献
325.
为满足潜艇水下悬停的战术需求,潜艇悬停系统必须控制潜艇按规定的稳定精度悬停在指令深度上,因此悬停系统运行品质对潜艇能否顺利完成战术任务较为重要。以模型潜艇为研究对象,在潜艇悬停运动基本数学模型、海洋环境干扰力模型和悬停水舱注排水控制模型的基础上进行仿真计算,研究悬停系统运行品质的3个关键指标,即流量计误差、悬停水舱注排水速率和最小注排水量对潜艇悬停操纵的影响,分析悬停系统运行品质与悬停稳定性之间的逻辑关系,研究结论可为悬停系统关键指标的设计优化和潜艇操艇系统的性能改进提供有益参考。 相似文献
326.
Gaspar L. Gil Gómez Alexander Lönnergård Mohit H. Asher Mikael Nybacka Egbert Bakker Lars Drugge 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(7):945-969
Objective testing of vehicle handling in winter conditions has not been implemented yet because of its low repeatability and its low signal-to-noise ratio. Enabling this testing, by identifying robust manoeuvres and metrics, was the aim of this study. This has been achieved by using both experimental data, gathered with steering-robot tests on ice, and simulation models of different complexities. Simple bicycle models with brush and MF-tyre models were built, both optimally parameterised against the experimental data. The brush model presented a better balance in complexity performance. This model was also implemented in a Kalman filter to reduce measurement noise; however, a simpler low-pass filter showed almost similar results at lower cost. A more advanced full vehicle model was built in VI-CarRealTime, based on kinematics and compliance data, damper measurements, and real tyre measurements in winter conditions. This model offered better results and was therefore chosen to optimise the initial manoeuvres through test design and simulations. A sensitivity analysis (ANOVA) of the experimental data allowed one to classify the robustness of the metrics. Finally, to validate the results, the proposed and the initial manoeuvres were tested back to back in a new winter campaign. 相似文献
327.
Eunjae Lee Jonghyup Lee 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(2):231-243
The cornering force and lateral static characteristics of a tyre are fundamental factors that describe the steering feel for handling performance. However, it is difficult to justify the contribution of each factor when the tyre’s cornering motion is evaluated through subjective assessment. Currently, the relaxation length of Pacejka’s tyre model is close to describing these tyre motions. Therefore, this paper proposes a string tyre model based on the relaxation length in order to represent the steering performance. The proposed method provides a more accurate modelling of the steering agility performance. Therefore, it is possible to use this model to predict the steering response performance, and this is validated through comparison with a real relaxation length. 相似文献
328.
应用系统科学和网络优化的思想、原理和方法,对港口物流系统结构和功能进行分析;然后简述各主要作业环节和各主要子系统通过能力;最后研究港口物流系统综合通过能力的协调理论和计算方法;同时用一算例进一步检验,提出提高港口物流系统综合通过能力的主要措施。 相似文献
329.
P. E. Pfeffer M. Harrer D. N. Johnston 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2008,46(5):413-428
For the on-centre handling behaviour of vehicles the steering system is absolutely important. To investigate the interaction of the vehicle and steering system a validated, especially tailored simulation model was developed. Some meaningful vehicle and steering system parameters are altered to show the influence on steering wheel torque, steering feel and understeer. The results underline the importance of an accurate steering system model. Identified measures to improve the centre feel and steering response were a stiffer torsion bar, a higher cornering stiffness or a lower overall steering ratio. The steering response, however, suffers when the centre feel is improved by a higher trail. The steering rack friction reduces mainly the steering response while the steering column friction decreases the centre feel whereas a stiffer torsion bar lessens the understeer tendency. 相似文献
330.