混合臂式高空作业车变幅系统动态建模与分析

Dynamic Modeling and Analysis of Luffing System for Mixed Arm Aerial Vehicle

针对混合臂式高空作业车变幅系统液压油缸驱动力难以显式计算的问题,借助拉格朗日方程和解析几何法对混合臂高空作业车臂架系统建立运动微分方程,得到臂架角位移、油缸行程与油缸受力随时间变化的动力学关系,在此基础上推导油缸油压、流量随时间变化的关系。给出臂架运动条件,基于最小二乘原理,运用MATLAB编程进行数值求解,得到油缸受力、油压及流量的时间历程曲线并对结果进行分析和验证。结果表明,模拟运动下油缸b1、b2、s1所受作用力较大,油缸设计时须优先对其进行强度分析;油缸b1、b2、s1油压变化也较大,油缸设计时须对其进行动强度分析;各油缸流量变化不大,可考虑使用定量泵节流调速系统。以上研究为混合臂式高空作业车臂架系统的设计及油缸选型等提供了参考依据。

In view of the problem that the driving force of hydraulic cylinder for mixed arm aerial vehicle luffing system was difficult to be calculated,the differential equation of motion was established by Lagrange equation and analytical geometry.Thus the dynamic relationship between the angular displacement,the travel and the force of the cylinder changing with time was obtained,and the oil pressure and the flow changing with time was also obtained.Giving the boom movement condition,the numerical solution of MATLAB was used to solve the problem based on the least square,and the time course of oil force,pressure and flow were obtained and the results were analyzed and verified.The results show that the force of cylinder b1,b2,s1 is greater and the cylinders should be given the priority for strength analysis;the oil pressure of b1,b2,s1 changes so much that dynamic strength analysis of the cylinders should be done;the flow changes not much so the use of quantitative pump throttling system can be considered.The above study provide references for the design of the boom system and the cylinder selection.