An Ontology-Based Framework for Decision Support in Assembly Variant Design

The designer generates a variant product by applying several design suggestions that fulfilled a variety of customer requirements. These design suggestions rely on multiple domains of expert knowledge, which are unstructured and implicit. Moreover, these design suggestions have an impact on assembly joint information (liaison), which makes the variant design a complex problem. To effectively support the designers, this work presents a knowledge-based decision support system for assembly variant design using ontology. First, a knowledge base is built by the development of an ontology to formally represent the taxonomy, properties, and causal relationships of/among core concepts involved in the variant design. Second, a five-step sequential procedure is established to facilitate the utilization of this knowledge base for decision-making in variant design. The procedure takes the extracted liaison information from the CAD model of an existing product as the input and further used for generating a set of variant design decisions as the output through Semantic Web Rule Language (SWRL) rule-based reasoning. The inferred outputs by the process of reasoning are the design suggestions, the variant design type required for each design suggestion, and its effect on joint information. Based on the evaluation of the ontology, the precision, recall, and F-measure obtained are 79.3%, 82.1%, and 80.67%, respectively. Finally, the efficacy of the knowledge-based decision support system is evaluated using case studies from the aerospace and automotive domain.

Variant design of farms using the LIRA-CAD program

This article is devoted to the study of the economic efficiency of using trusses of various outlines and sectional shapes. Today, metal trusses in large-span construction have practically no alternative due to fast production, installation, and most importantly, the quality characteristics they possess. This is an excellent ratio of the mass of the frame and its design load, durability, ease of installation and assembly, resistance to external influences. In practice, because of variant design, a constructive solution is determined that provides a minimum of costs for the acquisition of material, fabrication of the structure and installation. Within the framework of this work, it was determined and recommended when designing to use the obtained most economical constructive solution.

Configuration Equilibrium Model of Product Variant Design Driven by Customer Requirements

In view of the dynamic change of customer requirements (CRs) during the process of product use, in this paper we propose a Bayesian Nash equilibrium configuration model for product variant design driven by CRs. By analyzing CRs, the complete variant requirements of the products can be obtained. Combined with modularization and parameterization variant design methods, a parametric variant instance is proposed. Since cost and delivery time are affected by the product variant design, firms and customers are established as two decision-making bodies, and Bayesian Nash theory is introduced to the product configuration. The theory takes the product cost and customer satisfaction as the payoff function of the game, and based on the threshold value search of the customer satisfaction it determines the strategy set of the two parties. The Nash equilibrium solution equation is established and solved by a simulated annealing algorithm. The optimal product configuration scheme satisfying the interests of both sides of the game is obtained. Finally, the automatic guided vehicle (AGV) is taken as an example to illustrate the effectiveness and practicability of the method.

An approach to generating the sequence of part variant design based on information transfer utility

PurposeProduct variant design can only be achieved after all its constituent parts have been implemented by variant design. It is necessary to plan the sequence of part variant design reasonably. The product variant design process involves a large amount of information transfer events at the dimensional level. A reasonable product variant design process needs to make full use of the information transfer characters of parts to decrease the uncertainty of product variant design process. The existing methods of researching the product variant design process mainly focus on resource constraint and activity logic. They are deficient, however, in information transfer resolution and uncertainty management. This paper aims to address these issues.Design/methodology/approachThis paper identifies the number of dimension transfer paths and the position of dimension locating within a transfer path as being the key factors affecting the information transfer role of dimension. Information transfer utility is proposed to measure the information transfer capability of dimensions and parts. Based on these, a two-stage approach of generating the sequence of part variant design based on information transfer utility is proposed.FindingsThe uncertainty of dimension constraint network is minimal during the product variant design process when parts are implemented by variant design under the sequence generated through a two-stage method based on the information transfer utilities of parts, as does the times of parameter transferring and iteration in dimension constraint network.Originality/valuePart variant design under the sequence of descending information transferring utilities can decrease the difficulty of implementing product variant design validly and also increase the efficiency. This suggests an innovative method to planning the product variant design process reasonably from the perspective of informatics.