【作者】 任志峰；

【导师】 何耀华；

【作者基本信息】 武汉理工大学 ， 车辆工程， 2008， 硕士

【摘要】 防滑差速器是提高汽车性能的一项新技术,在国外汽车界得到了越来越广泛的应用。本文主要是将装制动介入式防滑差速系统和差速锁式汽车的性能进行对比研究。主要研究内容如下:分析了影响两种差速器传递转矩特性的各因素,并由此得出综合考虑各影响因素的两种差速器转矩的理论计算模型。根据对汽车运动过程中整体动力学的分析,建立了一个整车四轮动力学模型。该模型包括13个自由度:汽车质心处的速度ν、质心侧偏角β、横摆角ψ、侧倾角φ、前轮转角δ、四个车轮的角速度(ω₁₁、ω₁₂、ω₂₁、ω₂₂)、以及四个车轮的侧偏角(δ₁₁、δ₁₂、δ₂₁、δ₂₂)。模型中应用点接触轮胎模型,忽略悬架的作用,认为汽车在z轴（高度）方向上无位移;不考虑质心高度对汽车四轮轴荷重新分配的影响。根据建立的模型,列出动力学方程;根据模型的受力分析对动力学方程进行简化处理,得到最终的动力学方程,以便分析汽车的动力性和操纵稳定性。利用所建模型,详尽分析了两种防滑差速器对汽车在分离附着系数路面上的动力性（加速时间、最大爬坡度）以及汽车在转弯（汽车稳态回转运动、蛇行运动以及汽车在行驶时对操纵稳定性转向角阶跃输入时汽车的瞬态响应特性）的影响。同时本文根据此数学模型利用SIMULINK软件建立了汽车动力性以及操纵稳定性的计算机仿真模型。通过对装制动介入式防滑差速系统汽车与装机械摩擦片差速器汽车仿真结果的对比分析,看出了装制动介入式防滑差速系统汽车的动力性和通过性能有所提高,汽车操纵稳定性有所改善。本文对两种限滑差速器对汽车性能的影响进行了深入的分析,同时本文所作的工作使人们对两种限滑差速器的认识更加深刻,将会促使人们对两种差速器技术的研究与探讨,提高限滑差速器的设计与整车性能匹配的程度。并加快我国限滑差速器产品化的进程。更多还原

【Abstract】 Limited Slip Differential(LSD) is a new technique for improving the performance of vehicle. It gets more and more extensive application in the international car field.This paper makes research on the performance contrast of Braking force involvement Limited Slip Differential system and Mechanical friction disk type of Limited Slip Differential. Main contents are listed as follows:The paper analyzes the factors that influence the characteristic of transferring torque and gets the calculation model for computing the shear torque.On the other hand, with a view to analyze the wholly dynamics of the auto when driving, this paper establishes a the automobile model with the four wheels. This model includes 13 degrees of freedom. Making using of the established model, we can list the dynamics equation; After predigesting, it can gain the final dynamics equation, which can analyze the controllability and stability and the drivability.Making using of the established model, we can analyze the effect of LSD of power performance in split-road(acceleating time, max degree of slope)and controllability and stability(steady static circular Pylon course slalom test)when the automobile swerved to the automobile. At the same time, this paper also establishes a computer simulation model based on the mathematic model explained upward. After contrasting the result of the emluator of the LSD automobile to the common automobile, it is proved that the established model and the result of emluator are right. At the same time, the drivability, controllability and stability of the automobile that fixed braking force involvement Limited Slip Differential system are improved obviously.The research developed in this paper will promote the study of Limited Slip Differential (LSD) in our country more penetrately, and improve the accuracy of the theoretic analyzation and calculation in LSD. At same time, the research developed in this paper will make people well known more about LSD, and impel them to study the research of this new technique. This research will improve the matching degree between the LSD and vehicle’s controllability and stability in the design of LSD. Therefore, this research will accelerate the coming forth of the suitable domestic LSD product. In addition, the attempt of this paper on analyzing the vehicle’s dynamics by virtue of the computer simulation will promote the application of this technique in vehicle field.更多还原