共查询到19条相似文献,搜索用时 31 毫秒
1.
子装配体识别是解决大规模拆卸序列规划"组合爆炸"问题的有效方法之一.为了准确有效地识别与生成子装配体,在装配体零部件间接触关系、联接关系和向位妨碍关系及其相应图模型、矩阵的基础上,提出了一种基于图模型和判断矩阵的拆卸序列规划子装配体的识别算法.该算法利用图模型对子装配体集合做加法,利用判断矩阵对子装配体集合做减法,首先依据子装配体识别准则对图模型检索生成潜在子装配体集合,然后依据矩阵判断公式从集合中排除不符合连续性原则、稳定性原则和可行性原则的子装配体,并筛选理想个数的符合重量标准、同质标准和价值标准的最终子装配体集合.以减速器实例验证方法的可行性和有效性. 相似文献
2.
拆卸序列的紧凑表示是拆卸序列的评价与优化的基础,AND-OR图是拆卸序列表示的一种典型方法,但是拆卸序列的AND-OR图表示模型存在冗余信息。通过对AND-OR图模型作等价变换,消除AND-OR图表示模型中的冗余信息。设计了拆卸序列的优化表示模型的生成算法,建立了优化的基于OBDD的拆卸序列表示模型,用来表示复杂装配体的拆卸序列。并论证了优化模型的拆卸序列表示可以节省存储空间,最后的实验表明,基于OBDD的拆卸序列优化表示模型的存储空间远小于AND-OR图的存储空间。 相似文献
3.
4.
5.
为研究拆卸结构对动车组系统维修计划的影响,运用拆卸混合图模型分析单部件最优拆卸序列。并基于效费比分析方法选择多级维修方式,计算考虑拆卸成本和安装调试成本的部件最优可靠度阈值。在此基础上,引入机会维修理念,针对系统内多部件维修前拆卸序列规划问题,提出多拆卸目标序列优化方法,建立考虑可靠度价值浪费的动态机会维修策略模型。算例分析表明,动态机会维修策略相较于传统顺序预防性维修策略,通过归并维修时机,停机次数减少16次,有效减少因预防性维修和拆卸时间冗长造成的停机成本损耗,且维修总成本节省16.6%,满足维修部门对经济性的要求,为动车组系统考虑复杂相关性的维修策略研究提供理论支持。 相似文献
6.
基于模糊推理知识和模糊神经网络的理论,根据舰炮运转时发出的声音信号,提出了舰炮系统的故障检测诊断方案,详细介绍了信号提取的方法和故障分析的算法。 相似文献
7.
8.
9.
10.
分析了传统二元逻辑应用于核动力装置部分失效技术状态评估时的局限性,概述了Mamdani模糊推理的基本技术;结合状态评估实例,提出了基于Mamdani模糊推理的核动力装置系统级的技术状态评估方法,为系统部分失效的技术状态评估提供了一种新的技术途径。 相似文献
11.
C.M. Kang 《国际生产研究杂志》2013,51(22):6236-6248
With the increased need for remanufacturing of end-of-life products, achieving economic efficiency in remanufacturing is urgently needed. The purpose of this study was to devise a cost-minimisation plan for disassembly and remanufacturing of end-of-life products returned by consumers. A returned end-of-life product is disassembled into remanufacturable parts, which are supposed to be used for new products after being remanufactured. Each end-of-life product is disassembled into parts at variable levels and through variable sequences as needed, taking into account not only disassembly but also manufacturing, remanufacturing, and holding inventory of remanufacturable parts. This study proposes a mixed integer linear programming (MILP) model for derivation of the optimal disassembly plan for each returned product, under deterministically known demand and return flows. For the purposes of an illustrative example, the proposed model was applied to the formulation of an optimal disassembly and remanufacturing plan of ‘fuser assembly’ of laser printers. The solution reveals that variable-level disassembly of products saves a significant remanufacturing cost compared with full disassembly. 相似文献
12.
Increasing attention is being paid to remanufacturing due to environmental protection and resource saving. Disassembly, as an essential step of remanufacturing, is always manually finished which is time-consuming while robotic disassembly can improve disassembly efficiency. Before the execution of disassembly, generating optimal disassembly sequence plays a vital role in improving disassembly efficiency. In this paper, to minimise the total disassembly time, an enhanced discrete Bees algorithm (EDBA) is proposed to solve robotic disassembly sequence planning (RDSP) problem. Firstly, the modified feasible solution generation (MFSG) method is used to build the disassembly model. After that, the evaluation criterions for RDSP are proposed to describe the total disassembly time of a disassembly sequence. Then, with the help of mutation operator, EDBA is proposed to determine the optimal disassembly sequence of RDSP. Finally, case studies based on two gear pumps are used to verify the effectiveness of the proposed method. The performance of EDBA is analysed under different parameters and compared with existing optimisation algorithms used in disassembly sequence planning (DSP). The result shows the proposed method is more suitable for robotic disassembly than the traditional method and EDBA generates better quality of solutions compared with the other optimisation algorithms. 相似文献
13.
介绍了智能型CAPP系统的体系结构,研究了工艺实例分类索引树机制和基于模糊推理的工艺实例匹配算法,解决了具有复杂特征属性的工艺实例相似检索问题,实现了基于实例模糊推理的智能CAPP系统. 相似文献
14.
基于可信性理论的模糊环境下再制造生产计划 总被引:2,自引:0,他引:2
针对再制造系统生产计划问题,分析了再制造系统的特点。以一般再制造系统为原型,在可回收产品数量、单位产品拆卸时间、单位零部件再制造加工时间以及客户需求不确定情况下,考虑回收、拆卸、再制造加工、重新装配的能力限制,以总成本最小化为目标,构建了模糊再制造系统混合整数规划模型。利用可信性理论给出了模糊模型的清晰等价形式。最后,通过算例分析了不同置信水平选取对再制造成本的影响,验证了模型对再制造企业生产计划制定的适用性。 相似文献
15.
Within the realm of reverse logistics, remanufacturing has become renowned as a popular option in many reverse logistics settings.
In remanufacturing, firms take back products at the end of their use, disassemble them to obtain components, and reassemble
these components into a “good as new” remanufactured product. As a process, remanufacturing requires parts as an input, parts
which are gained mostly from recovered products. As the quality of the returned products are not known in advance, likewise
the amount of good quality parts recovered from the returned product is subject to uncertainty. In this paper, we develop
two heuristics of different sophistication which take into consideration that the yields of disassembly are stochastic. The
methodology is further illustrated with a numerical example, and performance of the heuristics is examined through a performance
study. The performance study indicates excellent performance for the more sophisticated heuristic, but also reveals under
which conditions the more simple heuristic can be recommended for application. 相似文献
16.
Design for end-of-life and design for disassembly are enabling design strategies for the implementation of business models based on the circular economy paradigm. The paper presents a method for calculating the effective disassembly sequence and time for industrial products. Five steps support designers in defining liaisons and related properties and precedence among components with the aim to calculate the best disassembly sequence and time. The effective disassembly time is computed considering the actual conditions of a product and its components (e.g. deformation, rust and wear) using corrective factors. This aspect represents the main contribution to the state of the art in the field of design for disassembly. The corrective factors are derived from a specific data mining process, based on the observation of real de-manufacturing activities. The proposed approach has been used for calculating the disassembly times of target components in a washing machine and in a coffee machine. The case studies highlight the method reliability of both: definition of time-effective disassembly sequences and assessment of effective disassembly times. In particular, a comparison of experimental tests shows a maximum deviation of ?6% for the electric motor of the washing machine and ?3% for the water pump of the coffee machine. 相似文献
17.
This paper presents a proof-of-concept novel near real-time interactive AR-assisted product disassembly sequence planning system (ARDIS) based on product information, such as interference matrix and 3D models. The system is developed using Unity and consists of three modules, including an intelligent disassembly sequence planning module, an automatic content authoring module and an intuitive augmented reality (AR) user interface (UI) with various features, such as a virtual panel for customisation and an option panel for sequence regeneration. Given the retrieval targets specified by a user, optimised disassembly sequences are computed using an evolutionary computing algorithm. For the sequences computed, the respective AR disassembly instruction sequences, such as 2D text instructions and animated 3D models, are generated dynamically based on a taxonomy that links each disassembly step in a sequence with the corresponding Unity templates that have been created beforehand. Hence, the need for manual authoring to provide AR disassembly guidance is reduced. If necessary, the user can request for alternative disassembly sequences which can be re-computed in near real-time. Several case studies have been carried out to demonstrate and evaluate the performance of the system within the laboratory environment. 相似文献
18.
拆卸建模是拆卸序列规划的基础,也是绿色设计的关键。在传统的拆卸序列规划过程中,随着产品零件数目的增加会造成“组合爆炸”问题。为解决该问题,提出了一种基于模块化设计思想的拆卸建模方法。首先,运用图论中有向图和无向图的概念分别表示零、部件之间的约束关系,并将有向图和无向图结合成混合图,建立产品混合图拆卸模型;其次,利用模块化设计中的模块划分原则生成子装配体,通过将模块化设计方法整合入混合图模型中,得到模块化设计的混合图拆卸模型,利用该模型可以有效地解决图论模型中边与顶点产生“组合爆炸”的问题;最后,以模块化设计的计算机主机箱的混合图拆卸建模为例来验证所提出的方法。 相似文献
19.
In a product life cycle, an assembly sequence is required to produce a new product at the start, whereas a disassembly sequence is needed at the end. In typical assembly and disassembly sequence planning approaches, the two are performed as two independent tasks. In this way, a good assembly sequence may contradict the cost considerations in the disassembly sequence, and vice versa. In this research, an integrated assembly and disassembly sequence planning model is presented. First, an assembly precedence graph (APG) and a disassembly precedence graph (DPG) are modelled. The two graphs are transformed into an assembly precedence matrix (APM) and a disassembly precedence matrix (DPM). Second, a two-loop genetic algorithm (GA) method is applied to generate and evaluate the solutions. The outer loop of the GA method performs assembly sequence planning. In the inner loop, the reverse order of the assembly sequence solution is used as the initial solution for disassembly sequence planning. A cost objective by integrating the assembly costs and disassembly costs is formulated as the fitness function. The test results show that the developed method using the GA approach is suitable and efficient for the integrated assembly and disassembly sequence planning. Example products are demonstrated and discussed. 相似文献