伸缩臂起重机起重性能迭代算法

Iterative method research on lifting capacity of telescopic boom crane

伸缩臂起重机起重性能的计算是整机设计的一个难点。为得到某种工况下的最大起吊质量,给定初始起吊质量,根据计算出的复合应力与许用应力的比值迭代出下一次计算的起吊质量,重新计算复合应力与起吊质量,直至计算出复合应力与许用应力差别很小的起吊质量,作为此工况下的最大起吊质量。文中提出恒增量法、比例法和拉格朗日法3种迭代算法,通过算例比较线性和非线性理论下不同迭代算法对计算的影响,结果表明:3种方法之中拉格朗日法的计算效率最高。

The calculation of lifting capacity of telescopic boom crane is a difficult point in the entire machine design.In order to obtain the maximum lifting mass under certain working condition,after the initial lifting mass is given,the lifting mass for next calculation was iterated based on the ratio of calculated complex stress to allowable stress,and the complex stress and lifting mass was re-calculated until the difference between calculated complex stress and allowable stress is very small,which is taken as the maximal lifting mass under this working condition.In this paper,constant increment method,proportional method and Lagrange method are proposed,by using examples,the influence on calculation by different Iterative methods under linear and nonlinear theories was compared.The result has indicated that it is the Lagrange method among three methods that the calculation efficiency is the highest.