外文翻译污泥处船用液压系统油路块设计研究.docVIP

毕业设计（论文）外文文献翻译 （本科学生用） 题 目：污泥处理船用液压系统油路块设计研究 学 生 姓 名： 学号： 学 部 （系）: 机械与电气工程学部 专 业 年 级: 09级机械设计制造及其自动化 指 导 教 师： 职称或学位：教授 2013年 2 月 10 日 外文文献翻译（译成中文1000字左右）： 【主要阅读文献不少于5篇，译文后附注文献信息，包括：作者、书名（或论文题目）、出 版 社（或刊物名称）、出版时间（或刊号）、页码。提供所译外文资料附件（印刷类含封面、封底、目录、翻译部分的复印件等，网站类的请附网址及原文】 Modeling of dynamic friction behaviors of hydraulic cylinders Abstract This paper deals with modeling of dynamic friction behaviors of hydraulic cylinders. Using hydraulic cylinders with different packing materials and sizes, friction characteristics are experimentally investigated under different magnitudes of external load. It is shown that the dynamic friction characteristics are affected by the packing material of the cylinder and by the pressures in the cylinder chambers. Comparisons between dynamic friction characteristics measured and those predicted by the modified LuGre model show that the model cannot simulate the real hysteretic behaviors of the friction force–velocity curve in the fluid lubrication regime. The modified LuGre model is improved by replacing the usual fluid friction term, which is proportional to velocity, with a first-order lead dynamics. It is shown that the proposed model can give accurate simulation results in the fluid lubrication regime. Keywords:Friction；Hydraulic cylinder；Mathematical model；Packing material；External load Introduction Friction is always present in a hydraulic cylinder system and has an influence on the efficiency and the motion (or control performance) of the system. In order to predict the behaviors of a hydraulic cylinder system or to improve its control performance, it is necessary to find an accurate mathematical model of friction of the hydraulic cylinder. Several mathematical models, which are used to describe the friction behaviors observed in mechanical systems, have been proposed in literature. However, these models can not predict the dynamic friction behaviors in the sliding regime