Chengen Wang

Internet of Things for Enterprise Systems of Modern Manufacturing

Design and operation of a manufacturing enterprise involve numerous types of decision-making at various levels and domains. A complex system has a large number of design variables and decision-making requires real-time data collected from machines, processes, and business environments. Enterprise systems (ESs) are used to support data acquisition, communication, and all decision-making activities. Therefore, information technology (IT) infrastructure for data acquisition and sharing affects the performance of an ES greatly. Our objective is to investigate the impact of emerging Internet of Things (IoT) on ESs in modern manufacturing. To achieve this objective, the evolution of manufacturing system paradigms is discussed to identify the requirements of decision support systems in dynamic and distributed environments; recent advances in IT are overviewed and associated with next-generation manufacturing paradigms; and the relation of IT infrastructure and ESs is explored to identify the technological gaps in adopting IoT as an IT infrastructure of ESs. The future research directions in this area are discussed.

AutoAssem: An Automated Assembly Planning System for Complex Products

To automate assembly planning for complex products such as aircraft components, an assembly planning and simulation system called AutoAssem has been developed. In this paper, its system architecture is presented; the main components and the key technologies in each component are discussed. The core functions of the system that have been focused include Digital Assembly Modeling, Assembly Sequence Planning (ASP), Path Planning, Visualization, and Simulation. In contrast to existing assembly planning systems, one of the novelties of the system is it allows the assembly plans be automatically generated from a CAD assembly model with minimal manual interventions. Within the system, new methodologies have been developed to: (i) create Assembly Relationship Matrices; (ii) plan assembly sequences; (iii) generate assembly paths; and (iv) visualize and simulate assembly plans. To illustrate the application of the system, the assembly of a worm gear reducer is used as an example throughout this paper for demonstration purpose. AutoAssem has been successfully applied to virtual assembly design for various complex products so far.

IoT and Cloud Computing in Automation of Assembly Modeling Systems

After the technologies of integrated circuits, personal computers, and the Internet, Internet of Things (IoT) is the latest information technology (IT) that is radically changing business paradigms. However, IoTs influence in the manufacturing sector has yet been fully explored. On the other hand, existing computer-aided software tools are experiencing a bottleneck in dealing with complexity, dynamics, and uncertainties in their applications of modern enterprises. It is argued that the adoption of IoT and cloud computing in enterprise systems (ESs) would overcome the bottleneck. In this paper, the challenges in generating assembly plans of complex products are discussed. IoT and cloud computing are proposed to help a conventional assembly modeling system evolve into an advanced system, which is capable to deal with complexity and changes automatically. To achieve this goal, an assembly modeling system is automated, and the proposed system includes the following innovations: 1) the modularized architecture to make the system robust, reliable, flexible, and expandable; 2) the integrated object-oriented templates to facilitate interfaces and reuses of system components; and 3) the automated algorithms to retrieve relational assembly matrices for assembly planning. Assembly modeling for aircraft engines is used as examples to illustrate the system effectiveness.

Conceptual design of remote monitoring and fault diagnosis systems

Condition monitoring and fault diagnosis are of fundamental importance for many industrial systems. In the last decade, substantial research efforts have been made on the surveillance and diagnosis systems for different types of equipment, with the approach of integrating information technologies and intelligent computing methods. This paper presents the conceptual design of a distributed information system of condition monitoring and fault diagnosis for a growing number of gas turbine-based power generation systems. Each individual information system that monitors a specific gas turbine system, locally deployed in a power plant, is linked to another information system, deployed at the manufacturers site, which oversees all the gas turbine systems in parallel. The systems are constructed on the basis of COM components, which are conceptually separated into three tiers. Subsequently, this paper proceeds to present a generic business domain model with components encapsulating physical entities of interest. Finally, this paper addresses the interactions among components, which considerably affect the performance of the system including efficiency and effectiveness. It has been identified that both asynchronous and synchronous communication mechanisms are required for exchanging information for different scenarios. COM+ services are also required for supporting object pooling, transaction coordination, and security control.

Object-Oriented Templates for Automated Assembly Planning of Complex Products

In the assembly modeling of complex products, it is not unusual facing an explosive growth of assembly relations, or called combination explosion. Through integrating object-oriented methods with the knowledge template based modeling, in this paper, a new methodology is proposed to deal with the complexity of the assemblies of large-scale products. As such, the templates with various assembly relations can be defined for complex products; constitutive parts or subassemblies in a product structure are defined as object classes; their features can be encapsulated, and defined or modified freely via the parameters of object classes to meet the requirements of a specific instance. The new method supports reusing knowledge and simplifying assembly modeling of complex products. In this paper, recent literatures on object-oriented methodologies and knowledge template methods for assembly modeling are reviewed, the rationales of object-oriented templates are discussed, and a method is proposed for creating assembly templates for complex products. In the case study included in this paper, the developed method has been applied to digital modeling of aero-engines, thus, validating its performance.

Parameter mapping and data transformation for engineering application integration

Enterprise applications may be classified into management applications used by managerial staffs for making decisions on business operations, and engineering applications used by engineers for solving multidisciplinary design problems. In the literature, enterprise application integration is extensively addressed in the context of management applications, but insufficiently discussed in the engineering disciplines. Practitioners in manufacturing industries have for a long time feel the increasing need of integrating engineering applications, in order to accelerate product development paces and improve design qualities. Integrating engineering applications used in the multiple engineering disciplines has to cope with a number of challenges. This paper focuses on one of the critical issues: parameter mapping and data transformation, which is of pivotal importance to integrating engineering applications. Design parameter mapping provides a consistent approach to data extraction, storage, display and manipulation among different data sources. Data transformation describes the operational logic of parsing input/output files, extracting and transforming data, and maintaining consistency among multiple data sources.

Integrated data management in complex product collaborative design

Scientific computing in complex product engineering design process has the characteristics of being tentative and iterative, which produces large scale intermediate data with heterogeneous formats and complex relationships, and the efficient organization and management of data becomes a bottleneck of product design performance. The concept of business component is introduced in this paper based on the modular analysis of the engineering process, and an integrated data management and storage framework is proposed for efficient heterogeneous design data management, in which XML schema, relational database and design files are synthesized. A network version management model is designed to enhance the design process and design object data management, which can describe both the individual objects evolution process and the inheritance relationships among multiple objects. Furthermore, key operations of version merge, submission and visualization are discussed. Finally the methods and technologies are implemented in an integrated management system for aerodynamic design of aero turbine engines (IMS-DATE).

Extended Interference Matrices for Exploded View of Assembly Planning

One of the tasks in assembly planning is to create the exploded views for the visualization purpose and the verification of assembly plans. In this paper, we introduce how to generate exploded views automatically from an assembly model. To increase the level of automation, a new relational matrix called extended interference matrix (EIM) is used to represent the assembly relations among constitutive parts. Information in an EIM is used to create the exploded views. An innovative method is developed to generate the exploded views based on the assembly sequences and EIMs. The corresponding Application Programming Interface (API) to the Unigraphics software has been developed as an integration of the algorithm with the CAD software tool. The assembly model of a gear reducer is used as a case study.

Implementation of remote robot manufacturing over Internet

Remote manufacturing allows companies to dynamically establish manufacturing alliances by exploiting advantages of enabling information technologies. Product data management and information integration are two of the most important issues for success of remote manufacturing. In this paper, we studied the two issues by taking a case of a remote manufacturing implementation in a robot manufacturing company. An integrated product data model and the related configuration management methods are developed. Under a hybrid architecture of Web browser/server and client/server, an application system is presented to manipulate the product data and to carry out a variety of manufacturing functions. Finally, a CORBA standards-based integration framework is proposed to achieve interoperability among multiple data and application objects over the Internet and company Intranets.

An integration architecture for process manufacturing systems

Given the significant differences between discrete and process manufacturing industries, specific integration architectures are required to accommodate the unique characteristics of process industries. In this paper, an architecture that encompasses view models, flow models and O-O models is developed, which gradually specifies the evolving design details through successive lifecycle stages of process manufacturing systems. In the architecture, products are distinctly modelled to reflect the impact of product data and to facilitate the development of customized products. A combination of object and agent concepts is adopted for building the models of process manufacturing systems. System constituent elements are respectively modelled as two types of entities: Namely the objects and agents. Objects are used to describe the passive constituent entities that possess no autonomy and conduct no functions, whereas agents are used to model the active entities that possess decision-making capabilities and perform operations on objects. One important advantage of the architecture is that it provides executable models at the implementation stage, which can be directly converted into application programs coded in object-oriented languages. Some models of the architecture are further discussed in depth and an information infrastructure based on CORBA standards is proposed for integrating the distributed data sources.