Product redesign using functional backtrack with digital twin

Digital twin, as a new industrial technology, provides great opportunities in various stages of product development. Product redesign is widely required in the process of product improvement, which is greatly depends on the functional analysis of product. Although traditional functional analysis can identify product design problems, the analyzed information is extremely detailed and verbose, which hinders the opportunity of product innovation. To expand the solution space for improving the innovation chance and ensuring solution quality of the product in the physical space, a digital twin is introduced in the redesign process. This study proposes a product redesign method using the functional backtrack obtained from a relational function model (RFM) to the hierarchical function model (HFM) with the digital twin. Based on a selected target product, the proposed method constructs the product RFM (sub-field) that originates from the reverse fishbone and relationships between components. Related parameters of components are obtained. A digital twin entity is built using the RFM (sub-field) and parameters based on the target physical product, and functions are extracted in the form of “verb + noun.” The RFM is formed considering four relations between functions. Furthermore, functions in the RFM are divided into various levels using the Dempster–Shafer theory based on functional levels and boundaries. In addition, the HFM is formed to indicate the level of problem functions and range area of the solution space. Components and parameters of harmful functions are obtained based on the digital twin entity. Creative ideas of product redesign are generated using the theory of inventive problem solving (TRIZ) to solve inventive problems at different functional levels. Technique for order preference by similarity to an ideal solution (TOPSIS) is introduced to evaluate and select solutions. Finally, the feasibility and effectiveness of the proposed method are verified in the redesign of an antenna mounted on vehicles.     

A method of constructing an inspiration library driven by user-perceived preference evaluation data for biologically inspired design

Biologically inspired design (BID) is one of the common methods for product design. To solve the problem of inaccurate acquisition of inspirational creatures due to the lack of user perception preference analysis, a data-driven intelligent service model for BID considering user perception needs is proposed based on Kansei engineering. Firstly, by extracting the perceptual features of creatures from the semantic source elements of products through mapping and encodes them, we proposed a data acquisition method based on intuitionistic fuzzy sets considering different customer preference distributions, bridging the gap caused by the asymmetry between designers and users. Secondly, the functional relationship between biometric features and user-perceived attributes is identified and predicted, and a predictive model of biodata considering user preferences is obtained by multiple linear regression analysis. Finally, based on the data clustering and reorganization theory to understand the organization and dynamics of the database, the construction of a BID library was completed, and the design resources in the library were used as analyzed knowledge for designers to plan design activities. Taking the bionic design of a UAV product as an example, a prototype of a computer-aided design service system was developed based on the theory proposed in the article, and the analyzed knowledge was used to improve the efficiency and science of the design, effectively verifying the usefulness of this study for design. To a certain extent, this study addresses the problem of cognitive limitations of designers and cognitive differences between designers and users, promotes the application of bioinspiration in product design, and improves the marketability of design solutions.     

Design and improvement of product using intelligent function model based cost estimating

Design is one of the most important activities in new product development. While the concepts of design for manufacturability and concurrent engineering have made significant advances in integrating the design function with other areas in the firm, there are still major gaps in timely and accurate costing information available to designers. Inappropriate design could result in high redesign cost and delay in product realization. The generation of design and improvement is a time-consuming and mentally exhaustion process. It involves combining design features to generate as much potential design as possible. As not all features combinations are feasible, decision-makers have to narrow down the potential solutions and subsequently select appropriate design for further development.This research suggests an intelligent function model based cost estimating for design and improvement of product. It is composed of three steps aiming at the low cost design of the product. The first step is setting up the optimal cost which is the engineering target based on the function. The second step is estimating the current functional cost according to the unit through the function analysis for basic model and quantitative. The second step estimates the current functional cost according to the unit through the functional analysis of basic model and quantitative. In the third step, the design of a unit is reviewed according to the priority of the difference between the optimal cost and the functional cost. Arranging the unit design parameter, the best design option is set-up according to the level. Also, it was actually proved through the application of “S” company.     

INTELLIGENT CAD SYSTEM IN CONCURRENT ENGINEERING ENVIRONMENT: A KNOWLEDGE-BASED APPROACH

The objective of this paper is to investigate specific methodologies for conceptual design and to establish a computational framework for an intelligent CAD system in a concurrent engineering environment. The main idea in developing such a system is to help designers in conceiving better design ideas within given sets of design, manufacturing, and assembly constraints. It is, therefore, essential to integrate intelligently diverse knowledge sources from different fields of manufacturing (e.g., design, process planning, assembly, inspection). When an object creation process is complete, the system analyzes the structure in consultation with its intelligent computational modules (“local experts”) to make sure that no functional, geometric design or manufacturing constraints are invalidated and to suggest an alternative better design, whenever possible. The paper also discusses the implementation of a prototype system for automated fixture design in the proposed concurrent engineering environment.     

Design for product experience: a study on the analepsis construction of product use

In the field of product design and development, product experience has started attracting a great deal of attention. However, assisting product designers to understand the concept of product experience, what sort of experiences they want for their products and how to include these into their design are topics that still need to be addressed. The aim of this study is to propose a design approach that begins with the use of narration and collects narration cases of product use for a specific product experience. This design approach guides designers through a four-step process, to develop a design model that fits in with the product experience. In order to better understand how this design approach works, this study takes the concept of analepsis as an example of product experience to demonstrate the process. The definition of analepsis, a term used in narratology, is “an event that took place earlier than the point in the story where we are at any given moment.” When the term is used in the product design field, it refers to use past experiences to solve current problems. This study explores the conceptual framework of the topic and proposes a product experience-orientated design model for product design, an issue that has rarely been discussed before. Directions for future research are also discussed.     

Knowledge-based manufacturability assessment: an object-oriented approach

To help the achievement of integrated product and process development, there is a need for tools that can assist designers in creating manufacturable parts with less design routines and tryouts. This paper presents a systematic approach to developing automated manufacturability assessment tools by identifying the functional and informational requirements and proposing an assessment model. The work presented in this paper includes: (1) identification of characteristics and tasks of design for the die-casting process; (2) determination of functional and informational requirements for automatic manufacturability assessment; (3) formalization and modularization of assessment knowledge; and (4) modeling of product definition data to support the assessment. Object-oriented techniques are employed to model the assessment knowledge and manage the complicated and diverse types of product definition data by taking advantage of data abstraction, modularity, inherent concurrence, and the concept of encapsulation and extendibility.     

A stakeholder-oriented innovative product conceptualization strategy based on fuzzy integrals

Knowledge, experiences and skills of corporate members promote new ideas into products, in the context of innovative design. This dynamism is especially important in the critical product conceptualization stage. In customer-oriented design paradigm, most methodologies focus on exploiting end-user requirements, instead of considering project stakeholder requirements in a holistic manner. Previous research in the area of innovative product conceptualization focused on such aspects as functional, cognitive, marketing and commercial perspectives. It involves the participations of customers, designers, engineers, marketers and business managers. Accordingly, a stakeholder-oriented innovative product concept development system (IPCDS) is established to integrate the bespoke four perspectives so as to evaluate product concept innovation comprehensively. To resolve the incomplete, ambiguous, uncertain and subjective nature of innovative design knowledge, the product platform represented in a design knowledge hierarchy (DKH) is generated using general sorting. Subsequently, an innovative design criteria matrix (DCM) constructed using repertory grids technique is rated with regard to specific design option. The ratings are then used as input features to the fuzzy integrals technique, for the purpose of innovative design. A case study on cellular phone design is used for system illustration and the results are discussed on the basis of product concept innovation.     

空间布局的约束图方法

空间布局的自动化是智能CAD领域的研究方向之一,旨在为设计师提供智能辅助工具，用于求解在建筑、厂房设备、大规模集成电路以及产品包装等等若干领域出现的布局问题.图论方法是空间布局研究的主要途径之一.以往的布局模型由于难以充分表达知识与约束,使得设计过程与结果难以控制.本文提出一种可应用于2D及3D布局的规范约束图及层次约束图模型,给出了约束图解的存在条件.该模型可以表示精细的布局知识与约束,在一定程度上克服了以往图模型不能充分表达布局知识与约束的不足.本文还给出了基于约束图的布局生成算法.     

基于深度学习的专利知识推荐服务研究

专利作为一种包含大多数领域中最完整的设计信息,可以为设计者解决设计问题提供有价值的指导。针对现有的专利推荐方法难以有效地推荐跨领域专利的问题,提出一种基于深度学习的跨领域专利知识推荐方法,用于创新产品的概念设计。对产品功能和知识需求情境进行建模,将设计问题进行标准化表达,生成设计问题空间。提出一种半监督学习算法（TG-TCI）将专利功能信息按照功能基自动分类和标记,利用实体识别算法（BERT-BiLSTM-CRF）提取专利应用场景术语、技术术语,结合国际专利分类（IPC）信息以表示专利的功能、情境、技术和领域属性,从而生成专利知识空间。通过设计问题空间到专利知识空间的功能基和知识情境映射查找所需的跨领域专利,根据技术和领域属性对它们进行聚类和评估,选出特定的专利以激发设计者的创造力。以一个实际案例进行分析验证,证明了基于深度学习的专利知识推荐模型的可行性及有效性。     

IMMUNITY AS A DESIGN DECISION MAKING PARADIGM FOR COMPLEX SYSTEMS: A ROBUSTNESS APPROACH

Within complex organizational systems such as Concurrent Engineering (CE) Product Development environments, uncertainty in information, and thus the knowledge required to make effective decisions, strongly influences the quality of the final product. Such systems are marked by high degrees of data variability making techniques such as optimization less than ideal, particularly for multiobjective problem types. Although different methods that enable designers to deal with uncertainty have been utilized, they derive from what appears to be a less than adequate representation of complex system behavior. This article presents a representation for complex systems based on the analogy of immunity where the environment of a system or “nonself” represents the set of input and outputs with the “self” of the system as the resulting “effect.” A fuzzy approach to the random perturbation of the system variables through the introduction of a global robustness index is proposed. The approach is presented in the context of decision making for tolerance control within manufacturing process design.     

Time identification of design knowledge push based on cognitive load measurement

The reuse of multidisciplinary design knowledge is pivotal in product development because of the increasingly fierce market competition. It can assist designers, particularly those who lack sufficient experience, in making correct decisions and achieving rapid design. Traditionally, designers primarily acquire design knowledge through information retrieval, which is typically time-consuming and inefficient. A solution that is widely considered to overcome the deficiencies of traditional knowledge retrieval approaches and actively provide designers with necessary knowledge is knowledge push. However, achieving the timely push of required knowledge to designers during the design process remains a challenging task. Accordingly, this paper presents a time identification method based on cognitive load measurement to identify the suitable time for design knowledge push. First, behavioral indicators related to the changes in cognitive load are identified by investigating the influence of the load on three types of behaviors: mouse dynamics, keystroke dynamics, and emotional states. Second, the possibility and efficacy of inferring the cognitive load by simultaneously and unobtrusively tracking the three aforementioned behaviors are considered through behavioral observations. Finally, predicting the knowledge push time based on the cognitive load using classification algorithms is investigated. The experimental results indicate that the accuracy of the proposed method in inferring the cognitive load is 55%, and that of push time is 83%.     

Virtual engineering at work: the challenges for designing mechatronic products

The product race has become an innovation race, reconciling challenges of branding, performance, time to market and competitive pricing while complying with ecological, safety and legislation constraints. The answer lies in “smart” products of high complexity, relying on heterogeneous technologies and involving active components. To keep pace with this evolution and further accelerate the design cycle, the design engineering process must be rethought. The paper presents a mechatronic simulation approach to achieve this goal. The starting point is the current virtual prototyping paradigm that is widely adopted and that continues to improve in terms of model complexity, accuracy, robustness and automated optimization. Two evolutions are discussed. A first one is the extension to multi-physics simulation answering the design needs of the inherent multi-disciplinarity of “intelligent” products. Integration of thermal, hydraulic, mechanical, haptic and electrical functions requires simulation to extend beyond the traditional CAD-FEM approach, supporting the use of system, functional and perception models. The second evolution is the integration of control functions in the products. Where current industrial practice treats mechanical system design and control design as different design loops, this paper discusses their integration in a model-based design process at all design stages, turning concepts such as software-in-the-loop and hardware-in-the-loop into basic elements of an industrial design approach. These concepts are illustrated by a number of automotive design engineering cases, which demonstrate that the combined use of perception, geometric and system models allows to develop innovative solutions for the active safety, low-emission and high-comfort performance of next-generation vehicles. This process in turn poses new challenges to the design in terms of the specification and validation of such innovative products, including their failure modes and fault-tolerant behaviour. This will imply adopting a model-based system engineering approach that is currently already common practice in software engineering.     

An object-oriented knowledge based Petri net approach to intelligent integration of design and assembly planning

Artificial intelligence can play an important role in the reduction of manufacturing costs and the enhancement of production efficiency and product quality. In order to assist designers in the early stages of a product development this paper develops an intelligent methodology for integration of design and assembly planning processes, including product design, assembly evaluation and redesign, assembly process planning, design of assembly system and assembly simulation, subjected to both econo-technical and ergonomic evaluations. A new unified class of object-oriented knowledge based Petri nets called OOKPNs, incorporating knowledge based expert systems and fuzzy logic into ordinary place–transition Petri nets, is defined and used for the representation and modeling of the distributed design processes. A prototype intelligent integrated design and assembly planning system (IIDAP) is implemented through distributed blackboard structure with concurrent integration of multiple cooperative knowledge sources and software. It consists essentially of the networked agents and the meta-system, each of which is a knowledge Petri net system with the capabilities of problem solving, learning and conflict resolution, and can be obtained through the inheritance, polymorphism and dynamic binding of instances of OOKPNs. In IIDAP system, both C/C++ language and COOL (CLIPS object-oriented language) are used to incorporate a Petri net tool, a geometric modeling and design tool, a planner and simulator and an evaluation tool. By use of this system, product design and assembly planning can be carried out simultaneously and intelligently in an entirely computer-aided concurrent design and assembly planning system. The design of manufacturable, cost-effective, usable products can therefore be achieved rapidly and flexibly. The developed methodology and system have been successfully applied to assembly design and planning of a micro switch.     

多目标驱动的产品形态基因网络模型研究

为解决产品设计过程中用户需求的主观性、模糊性问题,进一步提高产品意象传 达的准确度,提出一种多目标驱动的产品形态基因网络模型(M-FGN)构建方法。以品牌形象、 用户偏好、社会情境为驱动目标,构建多目标驱动空间;分析产品形态基因节点与边的设计, 以产品形态基因为节点,以节点之间的相关性为边,构建 M-FGN 网络;对网络进行拓扑分析, 析出隐性设计知识辅助设计师进行产品形态设计。以某国有企业 AGV 小车形态设计为例,通 过分析 AGV 小车侧面形态 M-FGN 网络,将析出知识提供给设计师进行针对性形态方案设计, 对子代方案进行对比评价,验证了 M-FGN 网络模型的有效性。     

Identity-based aggregate signcryption in the standard model from multilinear maps

Signcryption is a public key cryptographic method that achieves unforgeability and confidentiality simultaneously with significantly smaller overhead than that required by “digital signature followed by public key encryption”. It does this by signing and encrypting a message in a single step. An aggregate signcryption scheme allows individual signcryption ciphertexts intended for the same recipient to be aggregated into a single (shorter) combined ciphertext without losing any of the security guarantees.We present an aggregate signcryption scheme in the identity-based setting using multilinear maps, and provide a proof of security in the standard model. To the best of our knowledge, our new scheme is the first aggregate signcryption scheme that is secure in the standard model.     

On technology for functional requirement-based reference design retrieval in engineering knowledge management

Engineering design is a knowledge-intensive process, and includes conceptual design, detailed design, engineering analysis, assembly design, process design, and performance evaluation. Each of these tasks involves various aspects of technical knowledge and experience. Whether this technical knowledge and experience can be effectively shared is key to increasing product development capability and quality, and also to reducing the duration and cost of the development cycle. Consequently, providing engineering designers various query methods for retrieving engineering knowledge is one of the most important tasks in engineering knowledge management.The study develops a technology for functional requirement-based reference design retrieval as a decision support mechanism, which can assist engineering designers to retrieve relevant design and associated knowledge for reference in conducting functional requirements of a product. This study involves the following tasks: (i) designing a functional requirement-based reference design retrieval process, (ii) developing techniques related to the technology for functional requirement-based reference design retrieval, and (iii) implementing a functional requirement-based reference design retrieval mechanism. The retrieval process includes the steps of functional requirement-based query, case searching and matching, and case ranking. The technology involves (i) a structured query model for functional requirements, (ii) an index structures for historical design cases, (iii) functional requirement-based case searching and matching mechanisms, (iv) a functional requirement-based case ranking mechanism, and (v) a case-based representation of designed entities. Finally, the experimental example with indexing and retrieving similar designed entities is conducted to demonstrate the proposed techniques worked efficiently.     

Product interface design: A participatory approach based on virtual reality

The usability of the user interface is a key aspect for the success of several industrial products. This assumption has led to the introduction of numerous design methodologies addressed to evaluate the user-friendliness of industrial products. Most of these methodologies follow the participatory design approach to involve the user in the design process. Virtual Reality is a valid tool to support Participatory Design, because it facilitates the collaboration among designers and users.The present study aims to evaluate the feasibility and the efficacy of an innovative Participatory Design approach where Virtual Reality plays a ‘double role’: a tool to evaluate the usability of the virtual product interface, and a communication channel that allows users to be directly involved in the design process as co-designers.In order to achieve these goals, we conducted three experiments: the purpose of the first experiment is to determine the influence of the virtual interface on the usability evaluation by comparing “user–real product” interaction and “user–virtual product” interaction. Subsequently, we tested the effectiveness of our approach with two experiments involving users (directly or through their participation in a focus group) in the redesign of a product user interface. The experiments were conducted with two typologies of consumer appliances: a microwave oven and a washing machine.     

知识智能涌现创新:概念、体系与路径

快速变化的网络科技环境与创新需求,迫切需要相应的智能化创新理论与方法支撑。大数据及网络信息技术为创新机理的科学研究准备了条件。本文基于可拓学的基元理论,阐述了研究创新过程中海量知识的智能涌现机理的策略,以网络信息资源补充人脑隐性知识分享的不足,以模拟仿真技术实现创新路径的辅助生成,在一定程度上破解创新过程的“黑箱”困境,以解决创新的信息知识智能协同处理机理问题。智能创新理论的提出对丰富知识管理理论和科学创新方法具有较强的理论意义和实践意义。     

The push strategy of product design knowledge in cloud environment with the multidimensional hierarchical context and SSA-BPNN model

To assist designers in completing design tasks and improve the efficiency of product design, more and more design knowledge push approaches are coming about. With developments of information technology and cloud computing, knowledge service goes with the whole design process and it is represented by the knowledge push forming. The knowledge push is complex engineering, however, existing knowledge push approaches in traditional design patterns cannot exactly meet the personalized knowledge requirements of designers in cloud environment. To address this issue, we attempt to explore the push strategy of product design knowledge in cloud environment. Firstly, knowledge demands are analyzed with the multidimensional hierarchical context model and the design knowledge modeling is represented following characteristics of the cloud-based design pattern. Then, the knowledge push architecture contains the matching of knowledge to obtain alternative knowledge and the knowledge importance degree prediction with SSA-BPNN model to overcome the inaccuracy of judgments, which is put forward. Moreover, the push coefficient is calculated as the knowledge push reference. Eventually, an illustrative case of intelligent air conditioner product design in the cloud platform is taken to verify the application and performance of the proposed approach. We expect that this work could provide useful insights into the product design knowledge push in cloud environment.     

A process knowledge representation approach for decision support in design of complex engineered systems

Process knowledge is of considerable significance to the digitalization and intelligentization of the manufacturing industry. Current research on the process knowledge representation of decision-making in engineering design has predominantly focused on either mathematical models of individual decisions at the micro-level or organizational models of group decision consensus at the macro-level. However, the management of complexity and uncertainty in the model-based realization of engineered systems is critical to achieving rational, comprehensive, and robust decisions, especially in terms of knowledge-intensive design. The efficiency and effectiveness of decisions in system design are intrinsically linked to the process, knowledge, and system concepts involved, necessitating a more flexible and systematic decision process representation scheme that supports both the management of complexity and uncertainty. Hence, in this paper, we propose a decision-centric design process representation scheme named the Phase-Event-Information X (PEI-X) diagram and its corresponding systematic design guidance method for designing decision workflows. Using the proposed method, designers have the ability to (1) model hierarchical decision processes that cover vertical and horizontal interaction patterns, and (2) exploit the synthesis of the “Formulating-Identifying-Reusing-Exploring” iterative process to extend the understanding and prediction of decision process behaviors in design. We achieve the aforesaid abilities through the implementation of a knowledge-based design guidance system for collaborative decision support and we demonstrate the efficacy by adopting a specific multi-stage manufacturing process design problem, hot rod rolling system design, and carry out an integrated design of materials, products, and related manufacturing processes.