基于改进抛射弹丸算法的门式起重机主梁优化

OPTIMIZATION OF GANTRY CRANE GRIDER BASED ON IMPROVED PROJECTILE⁃TARGET ALGORITHM

桁架结构是门式起重机中最为常见的结构,具有轻盈、跨度大、用钢量省、受力体系简单等诸多优点。由于桁架结构非线性约束较多,通常无法快速高精度的获得最优解。为加快桁架结构的求解速度,提出一种基于考虑空气阻力的自适应线性权重系数策略对抛射弹丸算法进行改进。选取10杆平面桁架结构和25杆空间桁架结构对改进的抛射弹丸算法进行性能验证,结果表明,改进抛射弹丸算法的收敛速度相对于传统优化算法具有良好的竞争力。运用改进的抛射弹丸算法对门式起重机主梁进行轻量化优化,优化结果表明,主梁的质量由初始设计的34861.81 kg优化成2968.82 kg,降低的幅度为14.84%,主梁挠度由初始设计的2.57×10-3m优化成2.31×10-3m,降低幅度为10.12%。通过对桁架结构的优化结果分析,改进的抛射弹丸算法可以作为一种高效的优化算法进行求解工程优化问题。

Truss structure is the most common structure in the portal crane,which has many advantages,such as light weight,large span,saving steel consumption,simple stress system.Due to many nonlinear constraints of truss structure,it is usually impossible to obtain the optimal solution quickly and accurately.To deal with this challenge,an adaptive linear weight coefficient strategy based on considering air resistance is proposed to accelerate the projectile⁃target algorithm.The 10 bar plane truss structure and 25 bar space truss structure are selected to verify the performance of the improved projectile⁃target algorithm.Results show that the convergence speed of the improved projectile algorithm is competitive with the traditional optimization algorithm.The improved projectile⁃target algorithm is used to optimize the lightweight of the main beam of gantry crane.The optimization results show that the mass of the main beam is optimized from 34861.81 kg to 2968.82 kg,the reduction range is 14.84%,and the deflection of the main beam is optimized from the inital design 2.57×10-3 m to 2.31×10-3 m,with a reduction of 10.12%.By analyzing the optimization results of truss structure,the improved projectile⁃target algorithm can be used as an efficient optimization algorithm to solve engineering optimization problems.