基于机液联合仿真的剪叉机构疲劳寿命分析  

Fatigue Life Analysis of Scissor Mechanism Based on Mechanical and Hydraulic Co-simulation

作　　者：黄向明[1] 张特 尹人奇 刘国良 HUANG Xiangming;ZHANG Te;YIN Renqi;LIU Guoliang(College of Mechanical and Vehicle Engineering,Hunan University,Changsha 410082,China;SINOBOOMIntelligent Equipment Co Ltd,Changsha 410604,China)

机构地区：[1]湖南大学机械与运载工程学院,湖南长沙410082 [2]星邦智能装备股份有限公司,湖南长沙410604

出　　处：《湖南大学学报（自然科学版）》2021年第2期21-30,共10页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(51975203,51375154);湖南省创新创业技术投资项目(2017GK5011)。

摘　　要：为解决工程机械复杂机液结构的疲劳寿命计算问题,以某型号高空作业平台剪叉机构为研究对象,提出了一种基于机液联合仿真的结构疲劳寿命计算方法.首先,建立了剪叉机构的机液联合刚柔耦合多体动力学仿真模型,分析了剪叉机构在举升过程中的受力情况,确定了极限工况为举升阶段79.2 s时刻,提取了各关键铰点处的载荷谱;并通过剪叉机构的油缸压力和结构应力测试实验,验证了动力学仿真模型的正确性;然后,基于联合仿真确定的极限工况和铰点载荷谱,对剪叉臂进行了极限工况下和单位载荷作用下的静力学分析,得到了剪叉臂结构应力分布情况;最后,利用铰点载荷谱和剪叉臂结构应力通过仿真获得剪叉臂疲劳损伤云图,确定了剪叉臂疲劳危险部位主要是剪叉臂各个零部件的连接位置处,为后续的疲劳寿命优化提供了基础.In order to solve the fatigue life calculation problem of engineering machinery complex machine-liquid structure,this paper proposed a calculation method for structure fatigue life based on mechanical and hydraulic co-simulation technology,taking the scissor mechanism of a scissor aerial work platform as the research object.A multi-body dynamics simulation model of mechanical-hydraulic combined rigid-flexible coupling of scissor mechanism was established,and the force status in the lifting process of scissor mechanism was also analyzed.The ultimate working status was determined at the lifting stage of 79.2 s,while the load spectrum at each key hinge point was extracted.Under the same working status of simulation,the test experiments of oil cylinder pressure and structural stress were carried out.The experimental results verified the correctness of the dynamics simulation.Then,according to the load spectrum of the hinge point and the ultimate working status confirmed by co-simulation,the static analysis of scissors arms under the ultimate working status and unit loading action was carried out to obtain the static stress distribution of scissors arms structure.Eventually,by using the hinge point load spectrum and the static stress distribution,the fatigue damage and fatigue life of scissor arms were obtained.The results confirmed that the most hazardous part of scissors arms fatigue was the connecting position of each part of scissors arms,which provided a basis for subsequent fatigue life optimization.

关 键 词：剪叉机构 机液联合动力学仿真 刚柔耦合 载荷谱 疲劳寿命 

分 类 号：TH123[机械工程—机械设计及理论]