共查询到18条相似文献,搜索用时 125 毫秒
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为提高装配序列规划求解效率,在图论割集法的基础上,引入有序二叉决策图描述装配关联图、装配操作、装配几何可行性和装配稳定性.利用装配优先约束关系,简化装配关联图,设计了基于符号有序二叉决策图技术的装配序列生成算法,分析了该算法的时间复杂度.在每一次割集分解之后,检验子装配体的几何可行性和稳定性,实现装配序列生成过程中状态空间的隐式表示和搜索.研究实例验证了基于符号有序二叉决策图技术的装配序列生成算法的可行性和有效性. 相似文献
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作为复杂产品装配规划的有效求解策略,协同装配规划将复杂产品的装配规划结构按照装配要求分解为简单的子装配规划结构,子装配规划结构的最优或次优装配序列采用成熟的装配规划方法求解,通过装配序列合并得到产品的整体装配序列。协同装配规划所要解决的首要问题是装配规划结构分解,针对这个问题,提出装配单元规划方法。首先从产品可装配性的角度分析了影响装配单元规划的装配设计和装配工艺约束,并对归类的部分装配约束进行量化;进而基于模糊层次分析法生成装配单元决策图,采用最小生成树算法生成候选装配单元。同时,建立装配关系干涉矩阵对候选装配单元进一步验证,生成装配过程中互不干涉的装配单元。以一款电动机装配体为例验证提出的方法,结果表明该方法是一种求解装配规划结构分解问题的有效方法。 相似文献
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基于递归循环的层次化爆炸图自动生成方法 总被引:3,自引:1,他引:2
提出以递归循环和深度优先搜索层次化装配序列的策略自动生成复杂产品层次化爆炸图的方法。为使设计结构符合装配规划的要求,设计了可方便定义子装配体和编辑装配树的装配结构重构功能。为避免重复的干涉检测,研究干涉矩阵合成方法,通过对原始装配关系信息的整合,柔性化生成面向层次化结构的装配关系矩阵。为降低大规模序列规划问题的复杂性,将整体规划任务分解为若干个及若干层级子任务,子任务内采用多规则筛选算法,以基于干涉矩阵的几何可行性为前提,并行性、连续性、稳定性和方向性等为优化筛选指标,循环构建序列。提出递归爆炸算法,循环对层次化装配序列进行深度优先搜索,实时计算已爆炸零部件的累积包围盒,从而确定待爆炸零件位移矢量,自动生成间隔均匀有序、结构紧凑且空间层次感强的爆炸图。开发了基于Siemens NX的装配规划系统Auto Assem,以减速器及汽车部件实例验证了方法的有效性。 相似文献
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目前装配序列生成算法中缺乏动作分析研究,导致生成的虚拟装配序列在实际工程中并不能直接应用。深入分析了装配动作及其影响因素,给出了装配过程决策模式,构建了动作难度计算公式,基于计算公式进行了装配序列的进一步推论、证明,得到了计算复杂度非常小的装配序列生成规则,并以电脑装配为例验证了其可行性。 相似文献
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针对基于纯数学理论的装配序列生成方法难以显式地表示出生成合理的装配序列所需的知识和经验的语义问题,将本体引入装配序列自动生成的研究中。从装配体的子装配关系出发,结合定位关系、干涉关系和连接关系等装配信息建立装配信息模型。基于所建模型构建装配信息本体,并以本体规则的形式显式地表示知识和经验的语义。在所建本体和规则的基础上,通过本体推理判定装配序列的合理性,进而设计装配序列的自动生成方法。通过实例展示了方法的工作过程,同时验证了方法在减少不合理装配序列方面的有效性。 相似文献
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利用联结图方法建立设备的装配关系模型,生成联结矩阵,并利用子装配体的概念对模型进行简化.利用联结图模型分析零件间的优先约束关系生成优先关系矩阵,利用优先约束矩阵生成设备的可行装配序列,为设备装配序列选优提供基础. 相似文献
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Luc Laperrière Dr Hoda A. ElMaraghy 《The International Journal of Advanced Manufacturing Technology》1994,9(4):231-244
This paper describes a Generative Assembly Process Planner (GAPP) used to generate and evaluate assembly sequence alternatives which can be used in simultaneous engineering applications. Given a graph model of the product to be assembled, optimal assembly sequences are automatically generated and evaluated in a single process. Geometric feasibility and accessibility constraints on assembly operations which help prune the search space are presented. Assembly-related criteria which guide the search to an optimal solution are described. These include: number of reorientations, concurrent execution of assembly tasks, grouping of similar tasks and stability criteria. The relative weights of various criteria can be varied interactively resulting in different optimal assembly sequences. The ability of GAPP to generate and evaluate assembly alternatives when various criteria are enabled or disabled or their relative importance is changed makes it an effective tool for simultaneous engineering/manufacturing applications. Examples are included to demonstrate GAPP's use and potential for assessing assembly, disassembly, repair and maintenance procedures. 相似文献
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为提高装配序列规划求解效率和自动化水平,给出了装配体联结图模型、干涉向量和接触向量模型的有序二叉决策图描述,建立了基于符号有序二叉决策图模型及操作的可行装配序列生成技术.结合实例验证了基于有序二叉决策图的装配体模型和可行装配序列生成技术的正确性和可行性. 相似文献
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产品装配顺序的层次化推理方法研究 总被引:7,自引:0,他引:7
提出一种装配优先关系分类模型,将装配顺序规划过程中的各种装配优先关系分为几种优先关系,确定性工艺优先关系和模糊性工艺优先关系3类。并在此基础上,提出层次化装配顺序推理方法,分别从装配顺序的几何可行性、工艺可行性和工艺优良性3个层次,对装配顺序进行递进推理,最终得到性能优良的装配顺序。开发的产品装配分析软件原型系统--PAAS可以对复杂产品的装配顺序规划进行有效的分析和优化。 相似文献
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Assembly sequences merging based on assembly unit partitioning 总被引:1,自引:1,他引:0
Y. Wang J. H. Liu L. S. Li 《The International Journal of Advanced Manufacturing Technology》2009,45(7-8):808-820
Assembly sequence planning is a typical of combinatorial optimization problem which is difficult to be tackled when the number of parts of assembly becomes large. To reduce the searching space of assembly sequence planning of complex products, assembly sequences merging based on assembly unit partitioning is suggested. Assembly unit partitioning is presented to decompose the complex products into a group of assembly units containing a reduced number of parts or components, and the assembly design constraints and the assembly process constraints are comprehensively taken into account. The global optimal assembly sequences can be acquired through three steps. Firstly, the assembly units and decision graph of assembly unit are generated utilizing fuzzy analytical hierarchy process approach. Secondly, the optimal or near-optimal subsequences of assembly units can be obtained with current efficient methods of assembly sequence planning. Thirdly, under the assembly interference of assembly relations (geometrical constraints) of the whole products and the assembly precedence concluded by subsequences of assembly units, the assembly sequence merging is implemented to generate the global assembly sequences, and the optimal sequence is obtained through assembly sequences evaluation. The assembly constraints considered at the two previous steps is represented by the evaluation function. The effectiveness of the method is verified by an illustrative example and the results show that the searching space of assembly sequence merging of complex products is reduced remarkably and the optimal assembly sequence of the whole produces is obtained. 相似文献
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基于图论和子装配识别,提出了装配序列规划方法.把有向图理论运用到装配建模,提出了用有向装配关联图来表示装配关系.通过对装配体的结构分析,定义了子装配体,并且将子装配体进行分类.然后通过于装配识别和有向图割集,实现了装配序列规划的生成.此方法比单独的有向割集计算量少、产生的序列少.最后将该算法运用到阀门装配体中,验证了其有效性. 相似文献
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