电动挖掘机落物保护装置拓扑优化设计

TOPOLOGY OPTIMIZATION DESIGN OF AN ELECTRIC EXCAVATOR FALLING OBJECT PROTECTIVE STRUCTURES

针对某型电动挖掘机的乘员防护,提出使用基于等效静态载荷法的拓扑优化方法设计落物保护装置(Falling Object Protective Structures,FOPS)。首先,使用基于位移等效原则的等效静态载荷法,将动态非线性碰撞过程简化为多工况条件下的静态非线性变形过程。随后,提出使用加权系数法,将动态非线性拓扑优化简化为多工况条件下的静态非线性拓扑优化,可显著提高拓扑优化的计算速率和收敛性。最后,基于拓扑优化结果设计FOPS,并按照GB/T 17771—2010进行仿真试验分析。结果表明,新设计的FOPS无须额外加强即可满足乘员落物保护要求,且FOPS的总质量减轻了49.8 kg,这对降低工程机械的采购和使用成本,以及满足节能减排具有积极意义。

A new falling object protective structures(FOPS)was designed by a topology optimization method based on the equivalent static load method to improve the safety of the operator of an electric excavator.Firstly,the dynamic and nonlinear crush process is simplified into multiple static and nonlinear deformation processes based on equivalent displacement.Secondly,the dynamic and nonlinear topology optimization was transformed into static and nonlinear topology optimization involving multiple load cases by the weighting coefficient method.The computational cost was saved and the convergence was improved.Finally,a new FOPS based on the topology optimization result was numerically validated based on the GB/T 17771—2010.The results show that the new FOPS can meet the safety regulation without additional protective grill and the total mass of the FOPS is reduced by 49.8 kg which are positive to save the costs of procurement and operating and reduce the fuel consumption.