履带车辆行动系统及软地面的动力学建模与分析

发布时间：2017-12-31 07:17

本文关键词：履带车辆行动系统及软地面的动力学建模与分析　出处：《北京理工大学》2016年硕士论文　论文类型：学位论文

【摘要】：行动系统是履带车辆最基础的组成部分,是实现履带车辆高机动性、全地形通过性和轻量化的关键子系统。近年来随着大型多体动力学软件的广泛应用,针对履带车辆行动系统的动力学研究变的非常普遍。本文基于多体动力学软件LMS Virtual.lab Motion分别建立了履带车辆行动系统及软地面的动力学模型,并对模型车辆在特定工况下的越障性能和在软地面上的附着特性进行仿真分析。在行动系统建模方面,由于已有的大部分论文都将重点放在了后期对车辆性能的分析上,很少关注前期的建模过程,尤其忽略了软件内部对于接触力的计算过程,而行动系统的正常工作在很大程度上依赖于各部件、地面与履带板的接触,接触力的定义会直接影响模型的正确度及后期车辆性能的分析,因此,本文在行动系统建模方面主要对软件中接触力的作用机制从理论和应用上进行说明。首先介绍了LMS Virtual.lab Motion中计算接触力和摩擦力所采用的数学模型,详细描述了软件在处理接触碰撞时对于接触点的搜索过程。其次,说明了主动轮、负重轮、地面与履带板之间接触的定义方式。最后,重点分析了接触定义中最大碰撞深度、恢复系数和过渡速度这三个参数对接触力的影响。在行动系统仿真分析方面,利用所建的动力学模型分析了履带车辆通过崖壁的过程,提出了以低速接近崖壁然后以3m/s的速度通过崖壁的通过方案;用波长为不同履带板节距倍数的正弦路面作为激励,研究了履带的滤波效应对车辆平顺性的影响。在软地面建模方面,现有论文中均未提及履带板板体、履刺与地面的接触方式,且土壤参数的输入均采用软件中自带的参数,往往不知道此时土壤的含水率。本文针对这两方面的不足,在定义履带板与软地面接触方式时,提出了一种能较精确模拟板体与履刺的方法,土壤参数通过试验方法获得。通过土壤的压盘试验和直剪试验测得了10%含水率下沙壤土和粘土的土壤参数。在软地面仿真分析方面,从尽量缩短仿真计算时间的角度考虑,设计了“牵引法”测履带车辆地面附着系数的方案,并对沙壤土和粘土两种土壤的附着系数进行了测定。在模型验证方面,按照实车道路模拟试验工况,建立了履带车辆台架动力学模型,分析了模型在不同速度、不同路面下各个负重轮与车体之间的相对位移,并通过与实验数据对比,验证了模型的准确性。
[Abstract]:Action system is the most basic part of the tracked vehicle, is to achieve the high mobility of tracked vehicles, all terrain by key and lightweight system. In recent years, with the wide application of large-scale multi-body dynamics software, kinetic study for tracked vehicle operation system becomes very common. The multi-body dynamics software LMS Virtual.lab based on Motion respectively established a dynamic model of tracked vehicle operation system and the soft ground, and the obstacle performance in specific working conditions and vehicle model in soft ground adhesion characteristics were analyzed. The action of system modeling, because most of the existing will focus on the analysis of the performance of the vehicle late, very few pay attention to early modeling process, especially the process of calculation for the contact force and the normal work of internal software, operation system relies heavily on In each part, the ground and the crawler board contact, definition of contact force will directly affect the accuracy of analysis, and later the vehicle performance model so that the mechanism in the action of software system modeling main contact force is explained from theory and application. Firstly introduces the mathematical model for the calculation of contact force and friction force the LMS Virtual.lab Motion, a detailed description of the software in contact for the contact point of the search process. Secondly, the driving wheel and the wheel, defining the contact way between the ground and the crawler board. Finally, focus on the analysis of the definition of the maximum contact collision depth, influence coefficient and the transition speed three parameters of the contact force. In the action system simulation analysis, analysis of the tracked vehicle through the cliff process using the dynamic model of construction, put forward to speed close to natural cliff After taking 3m/s speed through the cliff by pavement scheme; sinusoidal pitch multiple wavelength for different track plate festival as an incentive, study the filtering effect of track effects on the vehicle ride comfort. In the aspect of the soft ground modeling, the existing papers were not mentioned in the track plate body, grouser contact with the ground. And the soil parameters were adopted as the input parameters of the built-in software, often do not know when soil water content. Aiming at these two problems, in the way of defining contact track plate and soft ground, put forward a more accurate simulation method for plate and grouser, soil parameters obtained by the test method. Through the test of soil pressure and direct shear test measured 10% moisture content of Xiasha loam and clay soil parameters. In soft ground simulation analysis, the computation time from the point of view as far as possible to shorten the simulation, the design of "pulling method" Test of tracked vehicle ground adhesion coefficient scheme, and the adhesion coefficient of sandy loam and clay of two kinds of soil were determined. In the aspect of model verification, in accordance with the real vehicle road simulation test bench, established tracked vehicle dynamics model, analyzes the model in different speed, the relative displacement between the wheels and the vehicle is different the road, and the comparison with the experimental data to verify the accuracy of the model.

【学位授予单位】：北京理工大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U469.694;TJ810

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