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遗传规划(GP)是遗传算法的一个重要分支,是提供找到解决问题的计算机程序的统一途径。矩形排料优化问题是NP完全问题,每块给定尺寸的板材上所排的矩形件数量随环境的动态改变而改变,类似于遗传规划中的分层特性,对应于不同深度的算法树个体。针对连接板下料中的排料优化问题,将连接板优化排料问题转化为矩形优化排料问题,提出一种全新的基于遗传规划的连接板优化排料算法。介绍了连接板的最小包容矩形的求取方法、遗传规划用于矩形件排料的算法及应用遗传规划进行矩形件排料的基本步骤,并用具体的排料实例进行验证。最后得到结论并指出未来可能的发展方向。 相似文献
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孙秀云 《机械工程与自动化》2007,(4):104-106
研究了机器人在已知环境下用遗传模拟退火算法进行最优路径搜索的方法,此算法兼备了遗传算法和模拟退火算法的优点,还对路径的转折节点处进行了光滑性的改进,并且通过仿真实验证明了此方法能够快速得到最优路径。 相似文献
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本文介绍了Ziegler-Nichols规则的PID控制器设计及其改进算法,并给出了基于MATLAB的实现方法和仿真。仿真结果表明此算法设计的PID控制器有良好的性能指标。 相似文献
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在计算机中执行算术表达式的计算是通过栈来实现的.编译系统不考虑表达式的优先级别,只是对表达式从左到右进行扫描,找到运算符和操作数,完成运算.本文以VB为开发平台,利用数组实现顺序栈工作原理,将中缀表达式转化为逆波兰表达式,便于计算. 相似文献
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基于遗传模拟退火算法的产品装配序列规划方法 总被引:3,自引:0,他引:3
为有效地获取方便可行的装配序列,在分析了装配序列的几何可行推理约束之后,建立了包含稳定性、聚合性及装配方向改变次数因素的优化评价模型。采用遗传模拟退火算法进行产品装配序列规划,通过分析算法的相关参数的变化趋势和大致范围,利用正交试验(初步定位)和对比试验(精确定位)相结合的方法,确定算法的近优运行参数,最后以8E150ZLC柴油机油泵为例,与遗传算法运行结果对比,验证了该方法是一种高效的、具有工程实际意义的复杂产品装配序列规划方法。 相似文献
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注射压力是影响挤出成型过程的关键因素之一,其控制水平的高低将直接影响产品的质量.因此对注射压力的控制不仅有数值上的要求,而且还要稳定、可控.针对目前PID控制器往往整定参数不良、性能欠佳的弊端,应用遗传算法的并行性特征搜索其全局最优解整定PID参数.仿真结果说明应用该算法优化得到的参数使得系统具有无超调量且调节时间短的优点. 相似文献
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A. Noorul Haq K. Sivakumar R. Saravanan V. Muthiah 《The International Journal of Advanced Manufacturing Technology》2005,25(3-4):385-391
An important problem that faces design engineers is how to assign tolerance limits. In practical applications, tolerances are most often assigned as an informal compromise between functionality, quality and manufacturing cost. Frequently, the compromise is obtained iteratively by trial and error. A more scientific approach is often desirable for better performance. In this paper, a genetic algorithm (GA) is used for the design of tolerances of machine elements to obtain the global optimal solution. The objective is to design the optimum tolerances of the individual components to achieve the required assembly tolerance, zero percentage rejection of the components and minimum cost of manufacturing. The proposed procedure using GA is described in this paper for two tolerance design optimization problems: gear train and overrunning clutch assemblies. Results are compared with conventional techniques and the performances are analyzed. 相似文献
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N. Lenin M. Siva Kumar M. N. Islam D. Ravindran 《The International Journal of Advanced Manufacturing Technology》2013,67(5-8):1777-1790
This paper presents the development of a genetic algorithm for determining a common linear machine sequence for multi-products with different operation sequences and facilities with a limited number of duplicate machine types available for a job. This work aims to minimize the total flow distance traveled by products, reduce the number of machines arranged in the final linear sequence, and decrease the total investment cost of the machines used in the final sequence. We assume that product flow runs only in the forward direction, either via in-sequence or bypass movement. We demonstrate the effectiveness of the proposed algorithm by solving a typical layout design problem taken from literature, and several randomly generated problems. Results indicate that the proposed algorithm serves as a practical decision support tool for resolving layout problems in manufacturing facilities. 相似文献
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Welding parameters optimization for economic design using neural approximation and genetic algorithm
Hsien-Yu Tseng 《The International Journal of Advanced Manufacturing Technology》2006,27(9-10):897-901
Welding is a basic manufacturing process for making components or assemblies. Recent welding economics research has focused on developing the reliable machinery database to ensure optimum production. It is an important issue, especially for the expensive equipment and the high quality preference in welding. An integrated approach is proposed to address the welding economic design problem. The integrated approach applies general regression neural network to approximate the relationship between welding parameters (welding current, electrode force, welding time, and sheet thickness) and the failure load. Analytical formula can be generated from the trained general regression neural network, and the mathematical model for the economic welding design can be constructed. An optimization method based on genetic algorithms is then applied to resolve the mathematical model and to select the optimum welding parameters. These parameters are used to obtain the preferred welding quality at the least possible cost. 相似文献
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Guoqun Zhao Hao Chen Cunsheng Zhang Yanjin Guan 《The International Journal of Advanced Manufacturing Technology》2013,69(5-8):1547-1556
The extrusion die plays a crucial role in aluminum alloy profile production, which influences product quality and service life of extrusion die directly. In this paper, a profile with irregular shape was taken as an analysis example, and multiobjective optimization for porthole extrusion die based on modern intelligence algorithm was carried out. Aiming at achieving the uniform velocity distribution in the cross-section of the profile as well as decreasing the maximum stress on the extrusion die and the deflection of the mandrel, the angle between port bridges, the position of die orifice, and the height of welding chamber were considered as the design variables. Then Kriging model was established on the basis of Latin hypercube samplings, and above design variables were optimized using Pareto-based genetic algorithm. Finally, an optimal die structure is gained. Compared with the initial scheme, the velocity distribution in the extrudate was more even, and the stress on the die and the deflection of the mandrel were decreased obviously in the optimal scheme. The optimal design method for porthole die has strong commonality, thus, it could give useful guidelines for practical production of the same kind of aluminum profile. 相似文献
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Injection molding optimization with weld line design constraint using distributed multi-population genetic algorithm 总被引:1,自引:1,他引:0
Chun-Yin Wu Chih-Chiang Ku Hsin-Yi Pai 《The International Journal of Advanced Manufacturing Technology》2011,52(1-4):131-141
Weld lines not only detract from an injection-molded part??s surface quality, but also significantly reduce its mechanical strength. It is not always easy to completely eliminate weld lines by simply adjusting the relevant injection mold design or the molding conditions. One solution is to prevent the weld lines from forming in regions that are structurally or aesthetically sensitive. The influence of weld lines on the quality of injection-molded parts cannot be overlooked and weld lines should be regarded as an important design constraint, especially for parts with aesthetic concerns. Since precisely predicting the number of weld lines and their positions and lengths is difficult without executing simulation routines, especially when part geometry is considered a design variable, this study adopts an enhanced genetic algorithm, referred to as distributed multi-population genetic algorithm (DMPGA), combining an optimization algorithm and commercial MoldFlow software with a dominance-based constraint-handling technique and a master?Cslave distributed architecture. MoldFlow obtains relevant data regarding warpage and weld lines and evaluates the corresponding designs. The dominance-based constraint-handling technique handles the weld line design constraint without needing additional penalty factors. Finally, the master?Cslave distributed architecture reduces the formidable computational time required for injection molding optimization. To illustrate the high viability of DMPGA, this study provides an outer frame of a digital photo frame as an optimization example. The results of this study show that DMPGA cannot only effectively decrease maximum part warpage without violating the weld line constraint, but also conquer hurdles attributed to constraint handling and computational demand. 相似文献
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Bin Huang Ke Xing Kazem Abhary Sead Spuzic 《The International Journal of Advanced Manufacturing Technology》2012,61(5-8):423-429
In the multi-pass rod rolling systems, where the final products are round bars with different sizes, oval-edging oval passes are widely employed as intermediate passes. This study attempts to present a generalized strategy to support the optimal design of oval-edging oval passes. A design system based on this strategy is developed to minimize power consumption, to reduce trials and errors in industry, as well as to improve the design efficiency and flexibility. A series of equations are established for geometrical modeling and graphic plotting of oval-edging oval passes, which can realize the parametric transformation for roll pass design and optimization. A novel formula based on statistical analysis and data fitting is proposed for the calculation of power consumption. To verify this formula, results obtained are compared with those calculated from using the Smirnov’s formula. The comparison confirmed the accuracy and efficiency of this formula. Finally, the proposed approach is applied for the optimal design of oval-edging oval passes, which are widely employed for the intermediate passes in the rod rolling systems. Through the comparison between simulation results and experimental data from literature, it is concluded that the proposed method can reduce power consumption of these passes and is able to improve the efficiency and flexibility of intermediate pass design without compromising its accuracy. 相似文献
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