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Propoes a methodology that enables a dynamic and interactive 3‐Dvisualization model of the assembly process to be developed from the CAD files of each part in the assembly. Makes three main contributions to the research in this area. First, a taxonomy of features for assembly is presented. Second, a process model for generating interactive 3D models of the assembly process is developed and, third, a new algorithm for creating a dynamic assembly model is derived. This algorithm, called the 3D assembly visualization (3AV) algorithm, involves instantiating the motion attributes that specify the motion of each part in the assembly. This dynamic assembly model is then converted to a 3‐D renderable format for visualization. An example is presented that uses virtual reality modeling language (VRML) as the 3‐D representation language. The result is a dynamic and interactive visual representation of the assembly operation. Such visualization can be of considerable use in DFA.

This paper aims to estimate the required insertion force and to analyze the influence of damping in a compliantly supported chamfered peg-in-hole assembly under dynamic conditions.

A mathematical model of the insertion process, including damping coefficient and stiffness of the compliance, insertion speed, mass, inertia and friction coefficient, has been developed. Computer aided design (CAD) model of the peg-in-hole assembly environment with passive compliance is created. The dynamic insertion force of the modeled environment is analyzed using multibody dynamics numerical solver.

The damping property of the viscoelastic materials used in the passive compliances suppresses the vibration caused due to the impulses in the transition of the peg in hole. It also increases the insertion force required for the peg insertion at the initial stage.

As the search strategies are not considered in this work, it is assumed that the initial contact is ensured between the chamfer and the peg of the assembly. A constant insertion speed is maintained throughout the insertion. Otherwise, it could have been varied at different stages of the insertion for reducing the assembly time.

The developed assembly model can be used for predicting the insertion forces of a chamfered peg-in-hole assembly and for designing/selecting the compliance device for the required assembly environment.

The proposed insertion model has considered the damping and elastic property of the compliance material as a parallel arrangement of spring and dashpot. This approach aids in modeling an insertion process closer to real-time assembly process.

This paper aims to provide a new dynamic modeling approach for root cause detection of the auto-body assembly variation.

The dynamic characteristics, such as fixture element wear and quality of incoming parts, are considered in assembly variation modeling with the dynamic Bayesian network. Based on the network structure mapping, the parameter learning of different types of nodes is conducted by integrating process knowledge and Monte Carlo simulation. The inference was that both the measurement data and maintenance actions are evidence for the improvement of diagnosis accuracy.

The proposed assembly variation model which has incorporated dynamic manufacturing features could be used to detect multiple process faults effectively.

A dynamic variation modeling method is proposed. This method could be used to provide more accurate diagnosis results and preventive maintenance guidelines for the assembly process.

Virtual assembly process plays an important role in assembly design of complex product and is typically time- and resource-intensive. This paper aims to investigate a dynamic assembly simplification approach in order to demonstrate and interact with virtual assembly process of complex product in real time.

The proposed approach regards the virtual assembly process of complex product as an incremental growth process of dynamic assembly. During the growth process, the current-assembled-state assembly model is simplified with appearance preserved by detecting and removing its invisible features, and the to-be-assembled components are simplified with assembly features preserved using conjugated subgraphs matching method based on an improved subgraph isomorphism algorithm.

The dynamic assembly simplification approach is applied successfully to reduce the complexity of computer aided design models during the virtual assembly process and it is proved by several cases.

A new assembly features definition is proposed based on the notion of “conjugation” to assist the assembly features recognition, which is a main step of the dynamic assembly simplification and has been translated into conjugated subgraphs matching problem. And an improved subgraph isomorphism algorithm is presented to address this problem.

Cables are widely used, and they play a key role in complex electromechanical products such as vehicles, ships, aircraft and satellites. Cable design and assembly significantly impact the development cycle and assembly quality, which is be-coming a key element affecting the function of a product. However, there are various kinds of cables, with complex geo-metric configurations and a narrow assembly space, which can easily result in improper or missed assembly, an unreasonable layout or interference. Traditional serial design methods are inefficient and costly, and they cannot predict problems in installation and use. Based on physical modeling, computer-aided cable design and assembly can effectively solve these problems. This paper aims to address virtual assembly (VA) of flexible cables based on physical modeling.

Much research has focused recently on virtual design and assembly-process planning for cables. This paper systematically reviews the research progress and the current state of mechanical models, virtual design, assembly-process planning, collision detection and geometric configuration and proposes areas for further research.

In the first instance, the main research groups and typical systems are investigated, followed by extensive exploration of the major research issues. The latter can be reviewed from five perspectives: the current state of mechanical models, virtual design, assembly-process planning, collision detection and geometric configuration. Finally, the barriers that prevent successful application of VA are also discussed, and the future research directions are summarized.

This paper presents a comprehensive survey of the topics of VA of flexible cables based on physical modeling and investigates some new ideas and recent advances in the area.

The product family assembly line (PFAL) is a mixed model-assembly line, which is widely used in mass customization and intelligent manufacturing. The purpose of this paper is to study the problem of PFAL, a flexible (evolution) planning method to respond to product evolution for PFAL, to focus on product data analysis and evolution planning method.

The evolution balancing model for PFAL is established and an improved NSGA_II (INSGA_II) is proposed. From the perspective of data analysis, dynamic characteristics of PFAL are researched and analyzed. Especially the tasks, which stability is considered, can be divided into a platform and individual task. In INSGA_II algorithm, a new density selection and a decoding method based on sorting algorithms are proposed to compensate for the lack of traditional algorithms.

The effectiveness and feasibility of the method are validated by an example of PFAL evolution planning for a family of similar mechanical products. The optimized efficiency is significantly improved using INSGA_II proposed in this paper and the evolution planning model proposed has a stronger ability to respond to product evolution, which maximizes business performance over an effective period of time.

The assembly line designers and managers in discrete manufacturing companies can obtain an optimal solution for PFAL planning through the evolution planning model and INSGA-II proposed in this paper. Then, this planning model and optimization method have been successfully applied in the production of small wheel loaders.

The purpose of this paper is to describe challenges the manufacturing industry is currently facing when developing future assembly information systems. More specific, this paper focuses on the handling of assembly information from manufacturing engineering to the shop floor operators.

Multiple case studies have been conducted within one case company between 2014 and 2017. To broaden the perspective, interviews with additionally 17 large and global manufacturing companies and 3 industry experts have been held. Semi-structured interviews have been the main data collection method alongside observations and web questionnaires.

Six focus areas have been defined which address important challenges in the manufacturing industry. For manual assembly intense manufacturing company, challenges such as IT challenges, process challenges, assembly process disturbances, information availability, technology and process control, and assembly work instructions have been identified and hinder implementation of Industry 4.0 (I4.0).

This longitudinal study provides a current state analysis of the challenges the manufacturing industry is facing when handling assembly information. Despite the vast amount of initiatives within I4.0 and digitalization, this paper argues that the manufacturing industry needs to address the six defined focus areas to become more flexible and prepared for the transition toward a digitalized manufacturing industry.

Notes that, until now, to route robotics travel, most investigations have utilized the fixed coordinate of placement points and magazine of the traveling salesman problem (TSP) method to sequence the placement points after the magazine has been arbitrarily assigned. Points out that, in fact, robotics travel routing should be based on a relative coordinate because the robotics, board and magazine simultaneously move at different speeds during assembly. Consequently, the coordinates of placement point and magazine are constantly changing. In this study, a novel tabu search (TS) based approach is presented. The proposed approach can arrange the placement sequence and assign the magazine slots to yield a performance better than the conventional one. Results presented herein also demonstrate that the larger the number of placement points and/or part numbers, the better the performance.

Automated robotic assembly on a moving workpiece, referred to as assembly in motion, demands that an assembly robot is synchronised in all degrees of freedom to the moving workpiece, on which assembly parts are installed. Currently, this requirement cannot be met due to the lack of robust estimation of 3D positions and the trajectory of the moving workpiece. The purpose of this paper is to develop a camera system that measures the 3D trajectory of the moving workpiece for robotic assembly in motion.

For the trajectory estimation, an assembly robot-guided, monocular camera system is developed. The motion trajectory of a workpiece is estimated, as the trajectory is considered as a linear combination of trajectory bases, such as discrete cosine transform bases.

The developed camera system for trajectory estimation is tested within the robotic assembly of a cylinder block in motion. The experimental results show that the proposed method is able to reconstruct arbitrary trajectories of an assembly point on a workpiece moving in 3D space.

With the developed technology, a point trajectory can be recovered offline only after all measurement images are acquired. For practical assembly tasks in real production, this method should be extended to determine the trajectory online during the motion of a workpiece.

For practical, robotic assembly in motion, such as assembling tires, wheels and windscreens on conveyed vehicle bodies, the developed technology can be used for positioning a moving workpiece, which is in the distant field of an assembly robot.

Besides laser trackers, indoor global positioning systems and stereo cameras, this paper provides a solution of trajectory estimation by using a monocular camera system.

Assembly systems require uninterrupted components' availability to feed workstations. This paper aims to propose a methodology to help managers in evaluating and selecting the most suitable policy for materials delivery to the shop floor. The analysis focuses on three basic policies, namely kitting, just in time kanban‐based continuous supply and line storage, even including class‐based hybrid policies.

Descriptive models are developed to design components' delivery systems and to compute their performances. Empirical criteria are utilized to associate specific policies to components classes in order to implement customized hybrid line feeding policies. A case study is then included to exemplify the method application and to show its capabilities as a decision making tool.

Hybrid feeding policies may be preferable to a single feeding policy common to all components. This is shown in a representative case study. However, in general there is a priori superior method and only a comparison of alternative feeding policies based on objective performance measures can determine the best approach in specific industrial applications.

The methodology is aimed at preliminary sizing and selection of alternative line feeding systems in deterministic environments. It is not intended for detailed performance analysis of assembly systems.

Production managers are given quantitative decision tools to properly select the components' delivery method at an early decision stage. This allows trade‐offs between alternatives to be explored in order to deploy customized feeding policies differentiated on components basis to better fit specific company requirements.

The paper extends previous descriptive models for line feeding systems and includes the possibility of hybrid policies.