共查询到20条相似文献,搜索用时 125 毫秒
1.
2.
3.
履带转向阻力系数大小的选取,对履带整机结构的设计有很大的影响,目前人们只考虑了转弯半径对履带转向阻力系数的影响,而往往忽略了履带沉陷量、履带中心距与其接地长度对其的影响。本文逐一对影响履带转向阻力系数的因素进行分析。 相似文献
4.
5.
6.
分析了可更换履带轮技术的发展现状与应用,总结了履带轮应向提高承重能力、扩大应用范围、提高通用性、舒适性和安全性的方向发展。分析了履带轮的基本组成和基架支撑形式,驱动形式,减震技术,防翻转技术和橡胶履带技术,得出不同技术形式在履带轮设计中的应用。总结了履带轮各系统设计中主要相关因素,提出了一种新型橡胶履带的设计方案。 相似文献
7.
8.
9.
10.
11.
12.
13.
对一批旧式挖掘机进行技术改造,将行走和回转机构优化设计为液压控制系统,使操作变得更灵活自如,取得了较好的综合施工实效。 相似文献
14.
15.
对铺轨机行走液压驱动控制技术进行了研究。铺轨机行走牵引车由履带牵引车和轮轨牵引车以铰接方式联接,其行走液压驱动系统包括履带泵控马达系统和轮轨泵控马达系统两部分。行走液压系统的控制目标是在不同工况下实现对给定速度的跟踪和两套泵控马达系统所提供的牵引力保持给定的匹配关系。文中首先分析了行走系统的控制特性,根据控制目标提出了基于牵引力和马达排量的前馈式PID的速度和力复合控制策略,在仿真中分别采用了基于常规PID和模糊PID的控制,并对仿真结果进行了分析。 相似文献
16.
研制了一种新型模块化可重构机器人系统,机器人由许多结构和功能完全相同的模块相互联接组成,通过改变各模块之间的联接状态和相互位置关系,不需任何外界辅助,自动完成重构过程和整体协调运动:设计了模块的分离联接机构和单自由度立方体结构,模块结构兼具阵列式和串联式特点,可方便的实现重构运动和整体协调运动:上位机软件系统可通过交互方式设置各机器人模块的方位,可手工编写或自动产生可重构机器人各模块的运动序列,可对机器人可重构过程和整体构型的协调运动进行规划和仿真,并通过计算机串口对机器人进行实时控制。试验验证了机器人模块的分离/联接和模块协作基本功能和蠕虫构型、四足构型、履带构型三种构型的整体协调运动功能。试验表明:模块结构设计简单合理,控制容易,可以完成重构操作功能和整体协调运动功能。 相似文献
17.
The brainstems of frogs contain many of the neurochemicals that are found in mammals. However, the clustering of nuclei near the ventricles makes it difficult to distinguish individual cell groups. We addressed this problem by combining immunohistochemistry with tract tracing and an analysis of cell morphology to localize neuropeptides within the brainstem of Rana pipiens. We injected a retrograde tracer, Fluoro-Gold, into the spinal cord, and, in the same frog, processed adjacent sections for immunohistochemical location of antibodies to the neuropeptides enkephalin (ENK), substance P (SP), and somatostatin (SOM). SOM+ cells were more widespread than cells containing immunoreactivity (ir) to the other substances. Most reticular nuclei in frog brainstem contained ir to at least one of these chemicals. Cells with SOM ir were found in nucleus (n.) reticularis pontis oralis, n. reticularis magnocellularis, n. reticularis paragigantocellularis, n. reticularis dorsalis, the optic tectum, n. interpeduncularis, and n. solitarius. ENK-containing cell bodies were found in n. reticularis pontis oralis, n. reticularis dorsalis, the nucleus of the solitary tract, and the tectum. The midbrain contained most of the SP+ cells. Six nonreticular nuclei (griseum centrale rhombencephali, n. isthmi, n. profundus mesencephali, n. interpeduncularis, torus semicircularis laminaris, and the tectum) contained ir to one or more of the substances but did not project to the spinal cord. The descending tract of V, and the rubrospinal, reticulospinal, and solitary tracts contained all three peptides as did the n. profundus mesencephali, n. isthmi, and specific tectal layers. Because the distribution of neurochemicals within the frog brainstem is similar to that of amniotes, our results emphasize the large amount of conservation of structure, biochemistry, and possibly function that has occurred in the brainstem, and especially in the phylogenetically old reticular formation. 相似文献
18.
在汽车车体构件制造中的辊弯成型工艺应用项目研究中,利用大型非线性有限元分析软件MSC.Marc研究了汽车B柱变截面辊弯成型仿真的有限元建模方法,主要包括板料模型和成型辊模型的建立、单元选择、边界条件、各种参数的设置及成型辊的速度加载等内容,然后采用刚性轧辊沿板料长度方向平动的方式对板料成型过程进行仿真模拟,分析了板料在... 相似文献
19.
LUO Ming-Je 《机械工程学报(英文版)》2007,20(3):67-70
In order to avoid the accuracy deterioration or tool damage caused by milling chatter, it is necessary to have an efficient and reliable diagnosis system that can on-line predict/detect the occur-rence of chatter. The diagnosis/predicting system proposed is to on-line process and analysis the vi-bration signals of the milling machine measured by accelerometers. According to the analysis results, the system will be able to detect/predict the occurrence of the chatter. The diagnosis algorithm is, first, collecting both the normal signals and chatter signals from milling processes, and then, converting the signals through wavelet transform and fast Fourier transform (FFT). Since the converted chatter sig-nals exhibit different characteristics from the normal signals, through defining the characteristic val-ues, such as root-mean-square value, max value, and ratio of peak value to root-mean-square value, etc, a diagnosis reference library that contains the distribution of these characteristic values is built for diagnosis. When a diagnosis is executing, the characteristic value of the measured signals is con-trasted with the diagnosis reference. The approach index which shows the possibility of occurrence of milling chatter will, then, be calculated through the diagnosis system. Cutting experiments are con-ducted to verify the proposed diagnosis system. The results show the success of early chatter detecting for the system. 相似文献
20.
设计了一个简易多功能计数器,由89C52单片机控制。配合相应的测量电路以及相应的软件,实现对频率、周期和时间间隔,被测信号峰值、温度等的测量,可记录10个历史数据,且具有掉电保持功能。其主要电路包括电平电路、时基电路、测频电路、测周电路、测温电路,键盘输入电路,显示电路等,信号输入后先自动判断频率的范围,然后选择需要的测量电路.通过单片机对数据进行处理,在误差允许的范围内显示各个测量值。 相似文献