Digital Production Line Research Articles

A quick response data collection and management system for digital twin production line based on cloud-fog-edge computing collaboration

Background A production line is the basic unit of smart factories and smart manufacturing. However, owing to the development of the industrial Internet of Things, sensors, and other technologies, more data are being collected, leading to a data explosion, and the heterogeneous nature of multiple sources makes it difficult to manage data in a unified manner. Methods A production line data collection, storage, and management system based on cloud-fog-edge computing collaboration and a digital twin was designed. Multi-source heterogeneous data were collected and transmitted based on the OPC UA, and an information model of the production line was established. Modules for data mapping, publishing, and receiving were developed to achieve unified data collection and transmission. The data storage and management platform was constructed by front-end and back-end separation technologies. Results The developed data collection and management system was verified for functionality and performance on a digital twin production line. Functional tests show that the system has the functions of data acquisition and transmission, device addition and viewing, device data querying and downloading, data and model visualization, and user rights setting. The average time for edge data collection and transmission is 183.6ms. The average response time of the cloud for fog requests is less than 1s. This shows that the system can satisfy the real-time requirements of a digital twin production line. Conclusions The proposed system is real-time and stable, providing support for big data and virtual-reality interaction in digital twins.

A Real-Time Monitoring and Diagnosis Method of Production Line Conveyor Chain for Digital Twin

<p>Aiming at the widely used digital production line and facing the digital twinning technology, this paper proposes a real-time monitoring and diagnosis method of the transmission chain status of the production line based on the digital twinning. First of all, the failure and failure mechanism of the conveyor chain is studied, and then a real-time data monitoring method is proposed according to the failure mechanism. On this basis, a data processing and analysis model oriented to the digital twin model is constructed. Then, artificial intelligence algorithm is incorporated into the model to improve the ability of the twin model to independently judge the failure and failure of the conveyor chain. Finally, the feasibility and efficiency of the proposed method are verified by experiments. The accuracy rate of fault diagnosis reaches 98.02%.</p> <p> </p>

Structural Spectrum of 2D Materials in Solution: Toward Establishing 2D Assemblies’ Digital Factory

AbstractThe numerous hierarchical architectures of 2D assemblies endow them with a new dimension to realize novel properties. From theoretical perspective, freedoms stem from in‐plane and out‐plane mechanical properties of 2D materials separately, which makes 2D materials embrace more than one “persistence length” giving rise to the diverse morphologies. However, the understanding of 3D architecture formation in 2D assemblies is still in its infancy. In fact, there is even no theoretical classification or reference to help clarify structural difference among numerous experimental obtained 2D assemblies. Based on the theoretical model composed by 2D sheets and Lennard‐Jones liquids, solution concentration dependence of 2D materials conformation is systematically studied, and a ln K behavior is uncovered that can realize the theoretical conformation prediction of 2D materials. More importantly, the digital production line (solution processing procedure) is set up toward establishing the 2D assemblies’ digital factory. The obtained structures may provide a reference to 2D assemblies, which benefits the understanding of the structural difference among different experiments and even help to guide the experimental design of 2D assemblies with targeted architectures and properties.

Construction and Practice of New Technology Course "Digital Design and Simulation of Production Line"

Digital Production Line Design and Simulation is a practical and comprehensive major course for electromechanical and automation majors in higher vocational colleges. This course is based on digital technology to construct automatic production lines, and uses virtual simulation and virtual reality combination technology for teaching, creating a new digital teaching ecology. In this paper, the teaching innovation means and methods are proposed, and specific exploration and practice are carried out for this course, which has achieved good teaching results.

Thermal Power Plant Turbine Rotor Digital Twin Automation Construction and Monitoring System

Based on the digital twin technology, this article investigates the physical rules fusion model of the turbine rotor operation in thermal power plants, establishes the geometric behavior mapping method of the turbine rotor in the virtual scenario of thermal power plants, and develops a real-time data-driven virtual monitoring system of the rotor operation, which realizes the virtual control of the rotor operation process from the physical and geometric levels, respectively. The 3D model created by Creo was imported into ADAMS in x_t format, constraints were added, and model data input and output interfaces were established in ADAMS software to build its dynamics model. The foundation of the joint simulation with the AMESim model is laid. The information fusion technology based on D-S evidence theory, fusing multisensor data and information from other channels, can more accurately and comprehensively understand and describe the diagnostic object, to make correct judgment and decisions on complex fault diagnosis. We propose an integrated modeling method for multiview control scenarios of manufacturing units based on digital twins and finalize the construction of digital twin models of manufacturing units based on the definition of the multiview model collaboration mechanism, which provides model support for the research of digital twin-driven manufacturing unit control technology. For the twin data perception and interaction problem, a unified architecture-standardized communication protocol is established based on OPC UA technology to solve the problem of difficult data perception and interaction caused by the nonuniform communication interface protocol of different devices on the automated production line. The model change is intended to help improve the visualization level of digital production line monitoring and improve the operating efficiency of the turbine rotor. The experimental results show that the application of digital twin to thermal turbine rotor operation monitoring provides a new method for turbine rotor vibration fault diagnosis; D-S evidence theory can fuse information from multiple aspects of the fault, thus improving the probability of fault diagnosis and reducing uncertainty.

Digital twin-driven intelligent production line for automotive MEMS pressure sensors

The equipment and technological processes used in manufacturing electronic products are gradually being automated and networked. Currently, digital twin technology continues to evolve and mature. The electronics manufacturing industry is undergoing an intelligent and digital transformation. Micro-electro-mechanical system (MEMS) sensors have been widely used in the automotive field due to their small size, low cost, and high reliability. In this study, a new intelligent production line for automotive MEMS pressure sensors driven by digital twin is individually designed. The intelligent production line system consists of physical production lines, digital production lines, twin data, and data service systems. The technology of multi-source heterogeneous data acquisition is used to process and analyze data collected in real time in a physical production line. Based on the technology of parallel control, the physical and digital production lines are synchronized. To obtain optimal process parameters, a process database is established through the analysis of the key processes of the production line. Three types of automotive MEMS pressure sensors are successfully manufactured in the constructed digital twin-driven intelligent production line. The intelligent production line can realize 24-h unattended operation. The product yield is above 98 %, and the takt time is less than 16 s.

A framework for development of digital twin industrial robot production lines based on a mechatronics approach

During the past years, intelligent manufacturing has attracted enormous attention from both academia and industry. Smart factories/workshops/production lines are important carriers for realizing intelligent manufacturing. However, there are difficulties in smart factories in processing multi-source heterogeneous data, in integrating virtual and physical worlds, and in achieving continuous and iterative optimization with real-time feedback. Digital twin, which is able to deeply integrate physical and virtual worlds, provides an important technology for easing the difficulties mentioned above. The construction of a digital twin system can solve the problem of data fusion, analysis, processing, and applications in smart factory. Digital production lines are the foothold of a smart factory. Building a digital twin production line can facilitate rapid practice of digital twins and promote the development of intelligent manufacturing. To this end, this paper proposes a development framework for a digital twin production line with closed-loop control based on a mechatronics approach. The detailed development process is given based on the framework. The framework proposed may provide some inspiration and insights for design and development of digital twin production lines.

Digital Twins-Based Production Line Design and Simulation Optimization of Large-Scale Mobile Phone Assembly Workshop

The mobile phone is a typical 3C electronic product characterized by frequent replacement, multiple product specifications, high flexibility, high-frequency production line switching, and urgent delivery time during production. Therefore, the optimized design of the mobile phone production workshop is crucial. This paper takes the assembly process of a specific type of mobile phone assembly as the research object and adopts the heuristic balance method to combine the production procedures. Moreover, it considers the automation degree of the process and the demand for production line rhythm to carry out station division and working hours design for the assembly process. The advantages and disadvantages of the plug-and-play production line and unit production line architecture are integrated, aiming at the production line’s construction cost and unit area capacity. A hybrid workshop with a mixed combination of two types of production lines is designed and an optimization model of hybrid workshop design is established. The semi-physical simulation technology of digital twins is utilized to verify the proposed design scheme to achieve the balance optimization of the production line, improve production efficiency, and reduce production costs. This work provides a technical scheme for designing and optimizing large-scale mobile phone assembly workshops with multi-batch and high-frequency production changes.

Digital twin-driven variant design of a 3C electronic product assembly line

Large-scale personalization is becoming a reality. To ensure market competitiveness and economic benefits, enterprises require rapid response capability and flexible manufacturing operations. However, variant design and production line reconfiguration are complicated because it involves the commissioning, replacement, and adaptive integration of equipment and remodification of control systems. Herein, a digital twin-driven production line variant design is presented. As a new technology, the digital twin can realize the parallel control from the physical world to the digital world and accelerate the design process of the production line through a virtual–real linkage. Simultaneously, the actual production line can be simulated to verify the rationality of the design scheme and avoid cost wastage. Four key technologies are described in detail, and a production line variant design platform based on digital twin is built to support rapid production line variant design. Finally, experiments using a smartphone assembly line as an example are performed; the results demonstrate that the proposed method can realize production line variant design and increase production efficiency.

Development of the Digital Site for Chemical Processes in the Manufacturing of Printed Circuit Boards

The article defines digital methods for controlling the quality of chemical processes. An architecture of a digital production line, which ensures the distribution of the computational load between the system components, is proposed. We considered the process of developing a prototype of a digital production site for servicing the etching operation during which controllable process parameters are determined; both hardware and software structures of the digital site are proposed. Studying the site operability, we determined the relationships between the process parameters, which made it possible to determine the boundaries of the designed system.

Multi‐dimensional digital twin of energy storage system for electric vehicles: A brief review

AbstractThis article proposes a Digital Twin (DT) framework for the whole life cycle of batteries. Specifically, in the stage of R&D, Digital twin can integrate the data of all technical fields into one model to optimize the battery's performance. During the manufacturing and production phase, DT can establish a digital production line and workshop to improve it. In the operation stage, aiming at various fault features in the battery operation process, with the assistance of large data samples, digital twin simulation is used to determine the fault status of the equipment accurately, to realize the self‐perception, judgment, error correction, early warning and other functions of the equipment. The article also proposes a Postoperation phase to recycle the battery to resolve the battery materials shortage problem. The critical research direction is a futuristic plan of battery communication with a charging Station, Battery Swapping System, Smart Grid, and Renewable resources. This sophisticated DT can comprehensively improve the energy system's entire life cycle management. Moreover, it can help perceive customer demand and offer an efficient operation mode to reduce running costs.

Transfer learning for the design of a digital twins-based automatic relay production line

At present, the world is experiencing a new round of scientific and technological revolution and industrial transformation. It has entered a historic intersection with the transformation and upgrading of the manufacturing industry, bringing new opportunities to the industry. Digital twins are considered as an effective way to realize the interaction and integration of the manufacturing physical world and the information world, attracting great attention from the relevant academic and business sectors at home and abroad. Specifically, they use virtual models and simulation technology to design industrial production lines and predict the future operation of equipment, which contributes to the efficient operation of intelligent production processes. Nonetheless, the key learning problem of accurate modeling should be solved, so as to adapt to the random and dynamic changes in industrial equipment design. Transfer learning, an innovative learning paradigm in machine learning, is developed to solve challenging learning problems with only a few or no labelled samples in the target field.

Design of Simulation Verification Platform for Ship Sub Assembly Digital Production Line Control System

The early verification of the control system of the sub assembly production line plays an important role in the efficiency and quality of the production line. The traditional control system verification is based on the actual production line and the cost is high. This paper proposes a simulation verification platform with data interaction with the control system, which can verify the control system at low cost. It can enable the ship sub assembly laboratory to have the ship sub assembly production line simulation, testing, and development capabilities to meet the research needs of the ship sub assembly production line.

Evolutionary Algorithm for Aerospace Shell Product Digital Production Line Scheduling Problem

The production of aerospace shell products is directly related to the safety and reliability of aerospace products. In this work, the aerospace shell product digital production line scheduling problem (ASPDPLSP) was studied, and a solution was developed. In the production process, it is necessary to decide the processing machine and time of each operation. In order to create a scientific shell product production plan, we propose an operation scheduling algorithm (OSA). Based on the constraints of the inspection process, the OSA has two heuristic task scheduling rules. Then, in order to further optimize the product production plan, an improved genetic algorithm (IGA) is proposed. Considering the repeatability caused by random search, a method for the initial population generation with similar and diverse characteristics is proposed. Two of these generation rules retain symmetry and randomness. IGA was used to optimize the order in which the products were processed, resulting in lower costs. Simulation experiments showed that the proposed algorithm solved ASPDPLSP well and provided suggestions to produce aerospace shell products.

Research on Quality Control of Digital Production Lines in Aviation Enterprises

Focusing on the requirements of efficient quality control of digital production lines in aviation enterprises, the framework quality control system of digital production lines were studied in this paper. First, the quality date categories of digital production lines were sorted out, a multi-source quality data acquisition scheme was proposed,. Second, the importance of key quality characteristics in quality control was discussed as well as a solution to find key quality features was established. Again, a multi-channel statistical quality control framework was constructed and a detailed implementation process was proposed. Finally, a digital production line quality control prototype system was designed and developed and validated in an aviation manufacturing enterprise.

Research on quality state perception of digital production line in aviation enterprise

With the development of intelligent manufacturing technology, the requirements of production process management have been improved. In view of the difficulty of the production line of a certain enterprise, the quality state perception frame and technical scheme of digital production line are put forward. and the key information types in the production line are combed.This paper presents a multi-source heterogeneous data model for the production process. Finally, the state-sensing system of digital production line is developed and applied successfully in an aviation enterprise.

Intelligent and Real-Time Information System of Production Manufacturing Based on Internet of Things Technology

China is a big manufacturing country, and the number of manufacturing enterprises with a certain scale is large. With the increasingly fierce market competition, manufacturing enterprises need to adopt new management methods, improve the market competitiveness of enterprises, and reduce the production cost. This requirement has large scale of market, and it has good economic and society profits. In this paper, the design for intelligent manufacturing information management system is proposed, and it can make the production process be digital and information. The process accuracy is improved, labor costs are reduced, and management efficiency is improved. It can promote the upgrade of production lines effectively, and it can reduce the production line improvement cost. This system not only helps to establish digital production line, but also makes the production manufacturing mode be reformed. It can promote management system, standard, method, and way of production manufacturing to be changed.

Virtual simulation of production line for ergonomics evaluation

To avoid ergonomic problems in the early planning stages of a production line and achieve more satisfactory planning and design, ergonomic simulation is particularly important in digital production line planning. An ergonomics analysis method is presented by using two theories: Ovako working posture analysis system (OWAS) and Burandt-Schultetus hand-arm force analysis (BSHA). The processes of ergonomics analysis and simulation are discussed based on a platform of process simulation and process designer. As an example, the paper shows how ergonomics problems are considered in production line planning to make a better choice between different production line planning schemes.

Ergonomics Simulation and Application in Production Assembly Line

In order to avoid the ergonomic issues in the early planning stages of production line, and to achieve a more satisfactory planning and design, the ergonomic simulation is particularly important in the study of digital production line planning. An ergonomics analysis methods was presented making use of these two theory of OWAS and BSHA. The process of ergonomics analysis and simulation was discussed based on the platform of Process Simulate & Process Designer. Finally, take an example, how to consider the ergonomics problems in production line planning was introduced to make a better choice between different production line planning schemes.

Geotest expands PXI digital product line with two new high-performance digital instruments

Geotest expands PXI digital product line with two new high-performance digital instruments