【作者】 孙立星；

【导师】 舒歌群；

【作者基本信息】 天津大学 ， 振动与控制， 2012， 博士

【摘要】 摩托车行驶稳定性、操纵平顺性和振动舒适性是车辆品质的重要衡量指标，需建立整车数学模型，求解其运动学及动力学微分代数方程，进行定性和定量分析。摩托车作为非树状结构多体系统，拓扑构型日趋复杂，包含机、电、液和控制系统，且向轻质高速化方向发展。由于其自由度数目众多，行驶工况复杂，若对整车系统进行过度简化降低自由度数，很难得到其动力学特性的精确定量分析。传统新车研发过程中，设计、试制及验证多反复进行，时间和资金成本倍数增加；有些性能试验受条件所限无法进行；悬架系统调校复杂；道路试验重复性差、不可控因素多，这些都制约摩托车研发及性能研究。本文采用多体系统动力学研究方法，在系统层面仿真分析摩托车虚拟样机在路面随机激励和发动机高频激励作用下的动力学响应特性；并考虑高速运转零部件弹性变形等非线性因素的影响，对其进行刚柔耦合动力学研究。论文主要研究内容和成果如下：1.本文根据多体系统拓扑构型建立摩托车数字化实体模型和人车路多体系统动力学模型，运用虚拟样机技术，比较分析整车集中质量简单模型和高度仿真虚拟样机模型的动力学特性，对摩托车动力学定量分析提出解决方案，并试验验证精确虚拟样机模型性能仿真分析的有效性。2.在ADAMS中建立轮胎力学模型，在MATLAB中根据功率谱密度计算路面不平度高程数据，导入ADAMS中建立不同等级路面三维模型，通过轮胎路面相互作用非线性仿真计算，对轮胎纵向滑移、侧向滑移以及回正力矩等重要性能进行研究，建立研究车辆主行驶动力学的可靠分析手段。3.高速车辆行驶动力学不仅要考虑路面激励作用，还要考虑发动机不平衡力和力矩的激励作用。本文建立发动机多体模型，考虑高转速下配气系统刚柔耦合多体动力学特性，研究车辆在路面、发动机联合激励下的动力学响应特性。根据虚拟样机技术和计算多体动力学分析方法，建立包含轮胎路面力学模型的摩托车多体系统，分析其虚拟试验环境中在路面和发动机联合激励下时域和频域中的动力学响应和行驶动力学特性，建立虚拟样机仿真试验下摩托车研发和动力学仿真分析的有效手段。更多还原

【Abstract】 As key performance index, riding stability, maneuverability and vibration comfortcapacity of motorcycle are investigated on the basis of the qualitative and quantitativeanalysis for algebraic and differential equation on the motion and dyanmics ofmotorcycle numerical model. Motorcycle is multibody system with sophisticatedtopological non-tree configuration made of mechanical, electricaly, hydraulical andcontrolling system, and turns to be high speed machine with lighter weight.Sincemotorcycle subjects to large degree of freedom and rough running condition, it is hardto make elaborate quantitative analysis for its dynamic behavior from the simplifiedmodel with lower degree of freedom. Simutaneously, in traditional design for newmotorcycle, repetitative cycle for design, mock-up and test is time-consuming andcostly; some performance tests are unpractical; non-linear suspension system is hardto adjust; road tests could not produce same results in repetition by moreuncontrollability, all above retard the procedure of motorcycle research anddevelopment. This paper is devoted to establish accurate motorcycle virtual prototypeon the basis of multibody system dynamics under road stochastic excitation and highfrequency engine excitation in order to fulfill the simulation for motorcycle dynamicresponse in systematical way, moreover, flexible multibody system is applied toinvestigate the dynamic behavior on the condition that non-linear elements is addedinto the system, especially with high speed parts flexibility. The main content andconsequence in this paper as follows:1. Apply vitual prototyping to establish motorcycle digital model andbody-vehicle-road multibody system, which work under virtual test environment. Thecomparison for dynamic property is performed between the simplified model ofvehicle lumped mass system and high-fidelity virtual prototype according totopological configuration and dynamical differential algebraic equation so that themethod of quantitative analysis of motorcycle dynamics, the effect of simulationanalysis by virtual prototype is also verified by real test.2. Establish tyre dynamic model in ADAMS while road roughness value in MATLABaccording to power spectrum density of different roads input into ADAMS to formroad model. In non-linear interaction between road and tyre model, simulation for tyrelongitudinal slip, lateral slip and aligning torque is fulfilled to be reliable analysisbasis for the research on motorcycle riding dynamics and vibration excitation. 3. The research on the vibration of motorcycle running at high speed should not focuson the road stochastic excitation, but need to determine the contribution of engineexcitation from unbalanced torque and force. The engine multibody virtual prototypeis established for the research on the dynamical property, for valve train working incomplicated way so that the deformation of major parts should be discussed in rigidand flexible multibody system coupled, the dynamics of which affects motorcycledynamic response to combined excitation.This paper established motorcycle multibody system with complicated topologicalconfiguration according to CAD geometry solid model and computational multibodydynamics, which is virtually tested under the interation between tyre model and roadmodel in order to analyze its dynamic response in time domain and frequency domainunder combined excitation from road and engine, so that vitual prototype ofcomplicated mechanical multibody system becomes an effective way for the researchand development of motorcycle and the simulation for its dynamic behavior.更多还原