高地隙三角履带底盘多体动力学建模与试验

Multi-body Dynamics Modeling and Experiment of Triangular Tracked Chassis with High Ground Clearance

摘要:

三角履带底盘具有高地隙、接地压力小、机动性好等优点，多体动力学分析是研究履带底盘运动特性的重要方法。以高地隙三角履带底盘为研究对象，建立了履带底盘各组件和车体总成的拓扑结构模型，分析了各部分之间的约束和运动关系；采用运动学和动力学手段分析了履带底盘行驶和爬坡的运动过程，构建了承重轮与履带接触模型、履带张紧力模型和履带-软地面接触模型；建立了高地隙三角履带底盘的三维模型，采用谐波叠加法构建了B级路面（水泥硬质路面）和E级路面（农田软质路面）的路谱，并进行了模型仿真与测试验证。结果表明，在硬质路面和农田软质路面上，所构建模型的平均速度误差率均小于1.50%，行驶偏移量误差分别为5.68%、4.89%，平均俯仰角误差不大于3%，说明高地隙三角履带底盘多体动力学模型具有较高的精度。

关键词:三角履带;农机底盘;多体动力学;拓扑结构;试验

Abstract:

Triangular crawler chassis has the advantages of high ground clearance, low grounding pressure, good maneuverability, etc. Multi-body dynamics analysis is an important method to study the dynamic characteristics of crawler chassis. The triangular crawler chassis with high ground clearance was studied and its topological structure model and car body assembly were constructed. The constraints and motion relationship between the various parts were analyzed. The motion state of the tracked chassis in the driving and climbing process was studied. The contact model between loadbearing wheel and crawler, the crawler tension model and the contact model between crawler and soft ground were deduced and analyzed. The road spectra of class B-level road (cement hard ground pavement) and class E-level road (farmland soft soil surface) were established by harmonic superposition method. Then multi-body dynamics simulation and experiment verification were conducted. The results showed that the average speed error rate of the established model was less than 1.50%. The distance offset error of hard road was 5.68%, and that of soft soil road was 4.89%. The average pitch angle error was no more than 3%. The data indicated that the established multi-body dynamics model of triangular crawler chassis had high accuracy. The research conclusions and methods can be extended to the dynamic investigation of other tracked chassis.

Key words:triangular crawler;chassis of agricultural machinery;multi-body dynamics;topological structure;experiment