【作者】 曹付义；

【导师】 周志立；

【作者基本信息】 西安理工大学 ， 车辆工程， 2009， 博士

【摘要】 基于液压机械无级传动原理的履带车辆液压机械差速转向系统能有效改善车辆的转向性能,是具有良好发展前景的一种履带车辆转向型式。本文采用理论分析、仿真计算及试验研究等方法,对液压机械差速转向系统的设计理论及方法、特性建模及仿真、车辆转向性能、转向系统参数匹配等方面进行了系统研究。论文在总结履带车辆及其转向系统发展现状及趋势,分析液压机械差速转向系统构成、工作原理、车辆转向性能和国内外研究及应用现状的基础上,提出了该转向系统研究的主要内容和需解决的问题。在对输出分流传动和输入分流传动两种基本的液压机械传动特性分析的基础上,根据履带车辆的转向要求,确定了一种新型液压机械差速转向系统传动方案,该方案具有结构简单、降速增扭等优点,适合农用履带车辆使用。设计了方向盘控制的履带车辆液压机械差速转向操纵系统,通过对转向操纵过程的分析表明能满足履带车辆转向性能的要求。对液压机械差速转向系统的转速、转矩、功率及效率等静态特性进行了分析,给出了转向系统性能与系统参数的关系,研究了履带车辆不同工况下系统内部的功率传递及系统效率的计算方法。建立了液压机械差速转向系统动态特性的数学模型及仿真模型,仿真研究了系统参数对系统动态特性的影响,仿真结果为履带车辆液压机械差速转向系统设计、参数匹配及性能优化提供了理论依据。根据履带车辆转向时接地履带、车辆与地面的相互运动关系,给出了履带滑转(滑移)及转向中心偏移时转向半径和转向角速度的计算关系。采用坐标变换,建立了履带车辆液压机械差速转向运动轨迹模型,通过转向运动轨迹仿真,分析了转向阻力的变化。建立了履带车辆液压机械差速转向动力学模型,根据提出的转向性能评价指标,仿真分析了履带车辆参数对其稳态和瞬态转向性能的影响,为实车应用研究奠定了基础。液压机械差速转向系统参数匹配是一个多指标、多变量的非线性优化问题,遗传算法是求解多指标、多变量非线性优化问题的一种有效方法。建立了利用遗传算法进行液压机械差速转向系统参数匹配的数学模型,并给出了参数匹配流程。对农用履带车辆液压机械差速转向系统进行了参数匹配,对匹配结果进行了校核,该匹配方法有助于液压机械差速转向系统开发。对不同工况下的液压机械差速转向系统特性及装备该转向系统的履带车辆转向性能进行了试验,通过试验数据分析,验证了理论分析的正确性。更多还原

【Abstract】 The hydro-mechanic differential turning system is a new-style turning mode using hydro-mechanic continuously variable transmission theory, effectively improves the turning performance of trackle vehicle, possessing widely developing promise well. The designing theory and ways, transmission characteristic model establishment and simulation of turning system, turning performance of vehicle, parameters matching of turning system are finished adopting theory analysis, simulation calculation, test research and etc in this paper.The development actuality of tracked vehicle and its turning system are introduced. The structure, working principle, turning performance and application and study actuality of hydro-mechanic differential turning system are emphatically discussed. The study contents and issue being solved are put forward.The hydro-mechanic transmission characteristic of output distributing transmission and input distributing transmission are theoretically analyzed. Combine to the turning demand of tracked vehicle, the hydro-mechanic differential turning system transmission scheme is decided, which has the simple structure, speed decrease and torque increase characteristic, adapt to the farm tracked vehicle.The hydro-mechanic differential turning manoeuvre system of certain tracked vehicle is provided. The turning performance of tracked vehicle can be fulfilled.The system rotate speed、torque、power and efficiency characteristic are theoretically analyzed. The formula of turning system and its parameters is given. The power transfering rule and efficiency calculation under different working conditions of this system are qualitatively studied. The maths and simulation models of dynamic characteristic of hydro-mechanic differential turning system are established. The system parameters influencing system dynamic characteristic are simulated. The theory base of design, parameters matching and optimization of hydro-mechanic differential turning system of tracked vehicle is provided by these simulation results.By analyzing turning kinematics of track vehicle, the calculating formula of turning radius and turning angular velocity considering track slip are educed. The hydro-mechanic differential turning trace model of tracked vehicle is established by coordinates switch. The turning trace simulation results can be used to turning resistance analysis. The hydro-mechanic differential turning dynamic model of tracked vehicle is established. The evaluation indexes of stable and dynamic turning performance are given out. The influence of design parameters and using parameters to stable and dynamic turning performance of tracked vehicle are studied using Newton-Raphson iterative method and simulation. This can help to actural vehicle using research.The parameter matching of hydro-mechanic differential turning system of tracked vehicle is induced to multi-goal, multi-parameters, nonlinear optimization question. The genetic algorithm is efficient way to solve this question. The maths models of parameter matching of hydro-mechanic differential turning system are established using genetic algorithm and the matching flow is put forward. The parameters matching of hydro-mechanic differential turning system of DFH1302R farm tracked vehicle is achieved and the matching result is satisified. The matching way can be used to design hydro-mechanic differential turning system.On different working conditions, the characteristic of hydro-mechanic differential turning system and turning performance test of tracked vehicle are performed. Basing test data, the theorictial research results meet turning requirment of tracked vehicle.更多还原