液压挖掘机回转功率切除系统仿真分析

分析挖掘机液压系统中较为先进的回转功率切除技术,并在AMESim软件平台上建立液压挖掘机回转系统模型,通过对模型相应参数的设置,实现机电液一体化系统的运动仿真.对比分析显示回转功率切除系统可有效提高整机在回转启动过程中的能量利用率.     

基于沙土路面挖掘机行驶稳定性的履带预紧力选取

履带预紧力对挖掘机行驶稳定性具有重要影响,选择挖掘机在软土路面行驶的工况,开展履带预紧力合理值选取的分析研究.基于虚拟样机技术,在Adams中分别搭建挖掘机整机动力学模型和沙土路面模型,并根据挖掘机驾驶室脚地板加速度和履带预紧力试验结果对虚拟样机模型进行验证.分析评估不同履带预紧力下挖掘机的行驶稳定性能,根据整机质心角...     

海拔6000米液压挖掘机动力适应性设计

通过查阅国标等资料,分析计算出液压挖掘机需要的高原海拔6000米环境条件相关参数,提出配套柴油机和整机参数的设计要求。分析环境条件对柴油机的影响,调整设计柴油机的供油系统,进排气系统、冷却系统,柴油机各项性能达到设计要求。调整设计整机的冷启动系统,采取措施防紫外线,采用适用高寒的材料,整机各项参数性能达到设计要求。     

三维CAD技术在液压挖掘机设计中的应用

以液压挖掘机为例,介绍挖掘机零部件和整机三维造型的基本方法和步骤,强调参数化建模的重要性。通过三维建模建成一个挖掘机的CAD设计平台,提高产品设计的科学性,缩短产品设计和试制周期。     

挖掘机闭式回转制动的研究

挖掘机作为一种主要的挖掘、装载工程机械 ,其回转系统性能作为整机的重要性能参数 ,对整机性能有着巨大的影响 ,如挖掘机作业的生产率和操纵的舒适性等 ,均受其制约。因而提高挖掘机的整机使用性能 ,则必须提高其回转系统的性能。在挖掘机回转系统中 ,除其回转速度指标参数外 ,回转制动性能在很大程度上又决定着回转系统的性能。由于挖掘机在其挖掘、装载生产作业过程中 ,回转制动对挖掘机工作装置起着作业定位的作用 ,因此回转制动性能的好坏 ,直接反映出挖掘机性能的好坏。国外挖掘机在发展过程中 ,回转制动经历了从开式回转制动发展到现…     

GJW111A型轮胎式液压挖掘机动力系统

考虑客户提出的节能、环保要求,需将GJW111型轮胎式液压挖掘机原发动机更换为满足国Ⅱ排放标准的康明斯发动机.设计改型产品GJW111A型轮胎式液压挖掘机的动力系统,在其他功能模块基本保持不变的情况下,根据负载的特点确定发动机参数和散热器参数.通过计算和分析,选择发动机及冷却系统,使匹配达到最优的效果,并保证挖掘机的动力性能,从而提高整机的工作效率,最大限度地满足客户需求.     

反铲液压挖掘机主参数优化研究

本文针对我国反铲液压挖掘机主参数设计方面的缺陷,提出了主参数优化方法。此方法从整机稳定性出发,以包络图面积和斗容为目标函数,综合考虑了主挖区性能以及众多的约束条件,对挖掘机主参数进行了优化,并给出了一优化实例。此方法能为我国制定“反铲液压挖掘机基本参数”提供理论依据。     

挖掘机多路阀失效模式数据库开发及应用

高压多路阀是挖掘机液压系统的核心部件,其可靠性决定整机的工作性能.为研究多路阀的失效模式,提升其可靠性,收集某中吨位挖掘机市场反馈的多路阀失效数据,并在此基础上建立多路阀失效模式数据库.该数据库提供多种查询与显示方案.从查询、分析、备份等方面介绍该数据库的核心功能,并结合失效案例进行威布尔分析,计算出β、η参数及其区间...     

TLC900型运梁车远程监控终端的主要电路及控制方法研究

采用高速、低功耗、抗干扰的STC12C5A60S2单片机作为TLC900型运梁车远程监控终端主控制器.在主要硬件电路设计方面,利用单片机的串口1与GSM/GPRS网络通讯模块通讯,串口2与GPS定位模块通讯.控制方法设计力求模块化、合理化,为提高整机的可靠性和抗干扰性奠定基础.     

大型履带式反铲液压挖掘机基本参数匹配研究

目前国内外市场大型履带式反铲液压挖掘机较少,国内200 t以上超大型机主要依靠进口。为了对大型液压挖掘机的基本参数有比较系统的认识,收集了国内外各大主流品牌50~800 t大型履带式反铲液压挖掘机样本,并对每个挖掘机样本的基本参数进行分类统计,对比分析基本参数和整机质量关系的走势,把整机质量与其对应基本参数的关系拟合成曲线,写出函数表达式,为大型履带式液压挖掘机新产品开发及结构改进提供参考。     

错综复杂的2011和高不确定性的2012——2011中国挖掘机械市场分析及预测

1总体情况挖掘机械分会统计调研数据表明,截止目前,在中国生产挖掘机械的企业有60多家,规划产能约60万台,代理商200多家,共生产和销售将近400种不同型号和规格的挖掘机械产品,单台整机质量为0.8~390t。     

中型液压挖掘机装配车间工艺设计

针对某中型液压挖掘机装配车间的工程设计任务,通过采用诸如助力机械手、多轴拧紧机、RGV系统、AGV系统、自动拣选系统、自行小车系统、地下输送系统、翻转变位机、结构件抓取机、结构件重型立体库、尾气收集系统等先进设备,显著提升生产率,缩短生产流程。实现了挖掘机装配过程的自动化和物料配送过程的无人化。     

A 3D model based control of an excavator

New technologies facilitate machine control systems, which use data from CAD and 3D measurement systems to automatically control construction machinery, such as an excavator. This paper examines the possibilities of controlling a six degrees of freedom (DOF) excavator with the final objective of controlling the movements of the excavator by using a positioning system such as a GPS in conjunction with a CAD model of the road surface. In comparison with the traditional 4 DOF machine, the excavator was provided with two additional degrees of freedom by applying a 2 DOF Rototilt, an accessory commonly in use. To study this problem, Msc.Adams with Matlab/Simulink was used as a simulation environment. In this paper the path of the bucket is calculated by using the CAD reference of the target plane.     

二手工程机械的流通与出口

在过去的10年中,中国经济迅速增长,需要大量的设备参与建设,可谓中国工程机械发展的黄金时代。在这个黄金的时代里,新工程机械的供应远远无法满足市场的全部需求,无论是工程机械制造企业还是代理商都更多地关注于新机销售而一直忽略二手工程机械的流通。     

Excavator tele-operation system using a human arm

It is difficult, for those without experience, to operate and manipulate a mechanical excavator. There is a long learning process to gain the skills required in operating the excavator's overall swing motions as well as movements of its boom, arm and bucket. In addition it is dangerous to operate such excavators on an inclined plane as this can lead to instability and puts the operator at great risk. In this study, a simple light weight tele-operation system has been developed for the excavator for dealing with these problems. Three sensors are attached to the operator's arm, in order to detect his movements. The operating commands for the actuators of an excavator will be transmitted via Bluetooth wireless communications. The new tele-operation system developed is simple, cost effective and lighter compared to typical haptic devices using a force feedback mechanisms. The operating algorithm has been modified and verified in many test cases. Prior to testing, the algorithms have been verified using the visual simulator, OpenGL. The operating system to operate the excavator easily and safely is developed and the control algorithm verified by tests.     

Modeling expertise and adaptability in virtual operator models

To advance construction machine design and testing, model-based design and virtual operator models (VOMs) can be used to explore machine designs virtually. However, current VOM efforts have been restricted to mimicking known trajectories, recorded from actual machine operations. Previous work developed a VOM to use in closed-loop simulation with an excavator model. To advance the utility of model-based machine testing, the fidelity of the VOM was enhanced along three lines: 1) representation of expert work cycle operation, 2) adaptation to changes in work site environment and 3) adaptation to changes when operating different machines. To represent expertise, work cycle task overlap was modeled – a hallmark of expert human operator performance. A mental model was developed to adapt to changes in the work site environment. Finally, the VOM was generalized to adapt to changes in excavator dimensions, eliminating the need for time intensive “tuning” typical of trajectory-dependent models. Three case studies demonstrated task overlap modeled productivity gains typical of expert operators, VOM control outputs adapted as trench depth and pile height increased, and the VOM adapted to different excavator models automatically. An additional case study compared VOM results to human-recorded data. This work advances the ability to integrate human expertise and adaptability in virtual operator modeling, resulting in a more realistic simulation of operations.     

基于网络控制系统的液压挖掘机伺服控制研究

为提升工程装备的远程操控能力,给某电控液压挖掘机引入移动自组网和总线控制系统.融合控制网与信息网,构建一个完全网络化的闭环多输入、多输出控制系统.针对挖掘机电液伺服系统和网络控制系统的特点,以Z-N整定PID为基础,设计了模糊PID控制器.通过仿真与试验,证明模糊PID比Z-N整定PID有更好的响应特性,能有效满足具有复杂非线性特征的挖掘机远程伺服系统的要求.     

Autonomous Navigation of Heavy Construction Equipment

Abstract: A John Deere model 690 excavator, mounted on a Standard Manufacturing Company wheeled undercarriage, has been automated for the purpose of autonomously uncovering and removing unexploded buried ordnance. This paper describes the development effort, with emphasis placed on the autonomous navigation of the excavator system. Accurate navigation is required in order to properly position the excavator system so that it can uncover and remove the target buried munition. Autonomous navigation is accomplished by use of an A_* search algorithm for path planning, an inertial navigation system (INS) integrated with a global positioning system (GPS) for vehicle positioning, and proportional control for path-following. Data gathered from eight navigation test runs show that the excavator, on average, can navigate to within 0.67 m of a goal position and to within 0.021 rad of a goal orientation.