基于整车动力学性能的菱形车前后悬架系统研究

发布时间：2018-03-28 21:16

本文选题：菱形车　切入点：前后悬架　出处：《湖南大学》2013年博士论文

【摘要】：随着汽车工业的不断发展，我国已经成为世界上的汽车制造大国，但是由于自主研发能力的欠缺，中国还远远不是汽车强国。同时，汽车保有量不断增加，其带来的负面影响也在不断凸显，交通拥堵、交通事故增加、燃料需求紧张以及环境污染等问题越来越受到社会的关注。菱形车是一款新型汽车，其底盘布置形式与传统汽车的矩形布置形式不同。菱形车四个车轮呈菱形布置，且前后车轮为单轮，承担着联动转向功能，中轮为驱动轮，这样决定了其在总布置以及悬架、转向、制动系统的设计等许多方面会与传统车辆有所不同。菱形车不仅具有完全的自主知识产权，而且在缓解交通、提高碰撞安全、节省燃油以及减少环境污染等方面具有自身的优势。但是，对于菱形车独特的底盘布置形式以及由此带来的一些结构上的创新设计，目前可供直接参考的理论和文献资料相对较少，要实现菱形车将来的产品化和市场化，还有大量的研究工作需要进行。本文在菱形车的平顺性、操纵稳定性、悬架参数设计以及悬架和车轮结构设计等方面进行了较为深入的研究，主要内容包括：确定了菱形车各悬架系统以及前后轮系统的基本结构。根据菱形底盘布置形式的特殊性，通过对传统悬架形式进行对比分析，确定双纵臂和双横臂独立悬架分别作为菱形车前后悬架和中悬架的基本形式。双纵臂独立悬架不仅适用于转向轮，而且有利于降低整车质心，可以满足菱形车对前后悬架基本要求，悬架和前后轮系统结构的确定有助于后续菱形车的整车性能分析以及优化等工作。建立了菱形车十五自由度整车平顺性模型，，并分别在随机路面和脉冲路面下分析了各设计变量对其平顺性的影响规律。根据菱形车的底盘布置特点，详细推导了菱形车整车平顺性的动力学模型，通过求解，分别得到驾驶员和左后乘员的垂向加权加速度均方根值和最大垂向加速度，从而对整车平顺性进行评价。平顺性模型是菱形车整车性能深入研究的一个理论基础，各设计变量对平顺性的影响规律也为菱形车总布置提供了理论参考。建立了菱形车二自由度和三自由度操纵模型，并分析了各设计变量对操纵稳定性的影响规律，同时对两个操纵模型进行了对比分析，发现了二者之间的不同。二自由度模型主要考虑侧向和横摆运动，而三自由度模型不仅考虑侧向和横摆运动，而且考虑侧倾运动，通过对菱形车的稳态回转、方向盘角阶跃输入和方向盘角脉冲输入试验的仿真研究，分析了各设计变量对菱形车操纵稳定性的影响规律，为菱形车总布置以及悬架参数选择提供了理论依据，也为菱形车操纵稳定性的深入研究奠定了理论基础。利用协同优化技术对菱形车的悬架参数进行了优化设计。菱形车悬架参数的变化对平顺性和操纵稳定性的影响存在矛盾性。优化前，通过菱形车样车试验对建立的平顺性模型和三自由度操纵模型进行验证，验证正确后以二者为基础，根据协同优化思想建立了菱形车悬架参数的优化模型，通过优化使得菱形车的整车性能在一定程度上得到了综合提高。优化后的悬架参数能够指导菱形车悬架结构设计，为其提供理论参考。利用近似建模技术，对菱形车前后轮系统的横梁结构进行了优化设计。根据菱形车的结构特点确定横梁的基本结构，并通过灵敏度分析确定横梁的关键设计尺寸，利用拉丁超立方方法建立横梁样本，再通过对各个样本的分析得到横梁的质量和疲劳寿命，从而利用Kriging近似建模技术建立横梁质量和疲劳寿命的近似模型，在此基础上以横梁疲劳寿命为约束条件，以横梁质量最小化为目标，对其关键设计尺寸进行优化设计。这种设计方法对于菱形车的横梁设计来说，可以大大地缩短设计时间，节约设计成本。本文的研究对菱形车整车设计参数选择以及前后悬架和前后轮的结构设计提供了理论依据，这不仅对菱形车的样车生产具有实际指导意义，而且为菱形车将来的产品化和市场化奠定了理论基础，具有很好的工程实际意义。
[Abstract]:With the development of automobile industry, China has become the world's automobile manufacturing country, but due to the lack of independent research and development ability, Chinese far from vehicle power. At the same time, the increasing amount of car ownership, its negative effect has been highlighted, traffic congestion, traffic accidents, environmental pollution and fuel demand such issues more and more attention of society.
Rhombic car is a new car, a rectangular layout of the chassis layout with the traditional car. Diamond car four wheels diamond shaped arrangement, and front and rear wheel is a single wheel, bear linkage steering function, wheel driving wheels, which determines its turn in the general arrangement and suspension, and many aspects the brake system design will be different from the traditional vehicle. The diamond vehicle not only has a completely independent intellectual property rights, and to ease traffic, improve safety, save fuel and has its own advantages to reduce the environmental pollution. However, to form the unique layout of the rhombic vehicle chassis and some structure resulting in the innovative design at present, for the direct reference theory and literature data is relatively small, to achieve the diamond vehicle future product and market, and there are a lot of work needs to be done. This paper in the Rhombic Vehicle The main contents include: ride comfort, control stability, suspension parameter design, suspension and wheel structure design.
The basic structure of the rhombic vehicle suspension system and rear wheel system. According to the particularity of the rhombic chassis layout, through the comparative analysis of the traditional form of suspension, determine the dual longitudinal arm and double wishbone suspension were used as the rhombic vehicle front and rear suspension and suspension. The basic form of dual longitudinal arm independent suspension is used not only for the on the steering wheel, but also reduces the vehicle mass, the basic requirements of the front and rear suspension can meet the rhombic vehicle, contribute to the subsequent diamond car vehicle performance analysis and optimization work to determine the suspension and front and rear wheel system structure.
A rhombic car with fifteen degrees of freedom vehicle ride comfort model, and respectively in random pulse road pavement and the design variables were analyzed on the ride comfort are studied. According to the characteristics of the diamond vehicle chassis layout, with the derivation of the kinetic model, the diamond vehicle comfort by solving the driver and passengers, left after hanging to the weighted RMS acceleration and maximum vertical acceleration are obtained, thus to evaluate the vehicle ride comfort. The model is a theoretical basis for further research of vehicle performance diamond car, effects of different design variables on the ride comfort also provides a theoretical reference for the diamond vehicle layout.
A diamond car two and three degree of freedom control model, and analyzes the influence of design variables on the operating stability, while the two control models were compared, found that the difference between the two. Two degree of freedom model considering the lateral and yaw motion, and the model of three degrees of freedom not only considering the lateral and yaw motion and roll motion, consider, through the steady turning of the rhombic vehicle, steering wheel angle step input and steering wheel angle pulse input test simulation, analysis of the effect of each design variables on the rhombic vehicle handling stability, provide a theoretical basis for the selection of diamond car general layout and suspension the parameters, lay a theoretical foundation for further research and handling stability for the diamond car.
The optimization of suspension parameters on the diamond vehicle optimization design was carried out on the change of rhombus vehicle suspension parameters contradictory effects on ride comfort and handling stability. Before optimization, the prototype test of the rhombic vehicle ride comfort model and three degree of freedom control model for verification, verification by two for according to the basis of collaborative Optimization optimization model established the diamond vehicle suspension parameters, through the optimization of vehicle performance makes the diamond car has been integrated in a certain extent improve. The optimized suspension parameters can guide the rhombic vehicle suspension structure design, and provide a theoretical reference for it.
By using the approximate modeling technique, beam structure on the diamond car front and rear wheel system was optimized. The basic structure of the beam according to the structural characteristics of the rhombic vehicle, and the sensitivity analysis of key design to determine the dimensions of the beam, using the Latin hypercube method to establish the beam, and then through the analysis of each sample was obtained and the fatigue life of quality the beam, thus using the Kriging approximation model of beam quality and fatigue life modeling technology, based on the fatigue life of the beam as the constraint condition, the beam quality is minimized as the goal, to optimize the design of the key design size. This design method for diamond car beam design, can greatly shorten the design time. Save the design cost.
This paper provides a theoretical basis for structure design of Rhombic Vehicle design parameters as well as the front and rear suspension and front and rear wheels, which not only on the diamond car prototype production has practical significance, but also provide a theoretical foundation for the future of the rhombic vehicle product and market, has the very good practical significance.

【学位授予单位】：湖南大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：U463.33

【参考文献】