2014年本科毕业设计论文模板

毕业设计（论文）任务书

摘要

V带传动是机械中广泛运用的一种传动方式，基于该传动的传统设计方法由于计算方法和手段等条件的限制，难以找出最优设计方案。本文拟在对V带传动设计进行深入分析研究的基础上根据实际问题需要建立相应的数学模型，采用遗传优化方法进行求解，通过设计适当的算法和编制相应的软件实现该传动的优化设计。本文主要研究了以下内容：

通过对优化问题的分析，以带轮体积和最小为优化目标，并以小带轮的基准直径和基准带长为设计变量，以小带轮直径，小带轮包角，中心距，带速及V带根数等限制为约束条件，建立了V带传动优化设计数学模型。在约束中小带轮直径约束、带速约束在求解过程中可以自动满足，而对于其余约束，采用静态罚函数法处理，将约束优化问题转换为无约束优化问题。

在遗传算法进行模型求解时，采用整数编码，并运用轮盘赌选择机制，算术交叉法和非均匀变异方法。由于本问题的优化目标是带轮体积和的最小值，用轮盘赌选择的个体为适应度最大者，为此将目标函数映射成适应度函数，并在转换时满足适应度单值、非负、连续、最大化的要求。针对整数编码，用1到Numd之间的整数与小带轮基准直径的标准值一一对应，由1到Numld之间的整数与基准带长的标准值一一对应，最终由一个长度为2的整数编码构成一条染色体。

最后，通过VB编制了优化设计程序。

关键词：普通V带传动；数学模型；优化设计；遗传算法；整数编码

Abstract

V-belt transmission is the extensive use of machinery in a drive way, the methods based on the transmission of traditional design, because of calculation methods and means of restricting conditions are difficult to find the optimal design. This paper on the basis of an in-depth analysis in the V-belt drive design in accordance with practical problems needs building a corresponding mathematical model, adopting the genetic method to solve, designing appropriate algorithms and developing the corresponding software to achieve the optimal design of the transmission. What the paper majors in are as following:

Through analysis of the optimization build a mathematical model, viewing the smallest sizes of the two pulleys as the optimization goal, the standard diameter of the small pulley and the standard length of V-belt for the design variables, and the small pulley's diameter, the corners, the center distance, the speed of the V-belt transmission and the number of V-belt for the constraints. The small pulley's diameter restraint and the speed restraint in these constraints can be automatically met, and for the remaining constraints static penalty function is adopted, then the optimization problem with constraints will be converted to a non-constrained optimization problem.

In addition, the paper on the genetic algorithm using integral coding and adopting the roulette gambling selection mechanism, the arithmetic crossover method and non-uniform mutation method. Since the goal is to optimize the pulley and get the minimum size, while through roulette gambling selection, the individual grown out of is of the greatest fitness, it needs mapping the objective function onto a fitness function. to connect with a standard value for length of V-belt one-to-one, and then by the end, constitute a chromosome of a length of 2 by integral Coding.

Finally, program for optimal design is made through VB.

Key words: ordinary V-belt drive; mathematical mode; optimal design; genetic algorithms; integral coding

目录

摘要 ................................................................................................................. I Abstract ........................................................................................................ II 目录 .............................................................................................................. III 第1章 绪论 ................................................................................................. 1

1.1 课题研究的意义及现状 .......................................................................................... 1 1.2 论文主要研究内容 .................................................................................................. 2

第2章 遗传算法基本原理 ......................................................................... 3

2.1 遗传算法简述 .......................................................................................................... 3

第3章 V带传动遗传算法优化设计 ......................................................... 5

3.1 优化设计数学模型的建立 ...................................................................................... 5 3.2 遗传算法求解 .......................................................................................................... 7 3.3 优化算例 .................................................................................................................. 9

结论 ...............................................................................................................10 参考文献 ....................................................................................................... 11 致谢 ...............................................................................................................12 附件1 ............................................................................................................13 附件2 ............................................................................................................15

第1章 绪论

1.1 课 …… 此处隐藏：6684字，全部文档内容请下载后查看。喜欢就下载吧 ……