Haw Ching Yang

Development of holonic information coordination systems with failure-recovery considerations

A holonic manufacturing system, designed to realize agile manufacturing, must (be able to) integrate the entire range of manufacturing activities from ordering, through design, modeling, production, to delivery. These activities are performed at many distributed sites. In order to effectively integrate these distributed sites, this work adopts distributed object and mobile object technologies, RosettaNet implementation framework, as well as holon and holarchy concepts derived from studying social organizations and living organisms to develop a holonic information coordination system (HICS). The generic holon is first developed by adopting the technologies of the distributed object-oriented approach with common object request broker architecture infrastructure, n-tier client/server architecture, a knowledge base, and data warehousing to achieve the properties of holon, error recovery, and security certification. The communication holon (CH) is then generated by inheriting the generic holon. Finally, CHs are employed to establish HICS. The CH exhibits basic holonic attributes, such as intelligence, autonomy, and cooperation. Furthermore, the CH can handle partner interface processes, and data exchange by various data formats following the standards of RosettaNet business messages. The failure recovery mechanism of the CH causes HICS to be more reliable than legacy systems. As such, HICS can meet the future requirements of supply-chain information integration of virtual enterprises.Note to Practitioners-An HICS that handles the information flow of the supply chain is proposed in this work. HICS is composed of many communication holons (CHs). Any company that would like to use HICS to exchange information for enterprise integration may possess a CH. The CH is implemented with the Java web-start technology. Therefore, any company can download a CH from the web server via a web browser. The company is, then, able to communicate with other members throughout the supply chain. Accordingly, CHs are scattered throughout the Internet/intranet and each CH can act as both an information supplier and an information consumer. Further, because the CH adopts the RoesettaNet implementation framework (RNIF), any company that has the capability of RNIF can also communicate with the members in the HICS framework via RosettaNet business messages.

Modeling and analysis of equipment managers in manufacturing execution systems for semiconductor packaging

Equipment Managers (EMs) play a major role in a Manufacturing Execution System (MES). They serve as the communication bridge between the components of an MES and the equipment. The purpose of this paper is to propose a novel methodology for developing analytical and simulation models for the EM such that the validity and performance of the EM can be evaluated. Domain knowledge and requirements are collected from a real semiconductor packaging factory. By using IDEFO and state diagrams, a static functional model and a dynamic state model of the EM are built. Next, these two models are translated into a Petri net model. This allows qualitative and quantitative analyses of the system. The EM net model is then expanded into the MES net model. Therefore, the performance of an EM in the MES environment can be evaluated. These evaluation results are good references for design and decision making.

Development of a collaborative and event-driven supply chain information system using mobile object technology

Information integration of the supply chain for the manufacturing industry is essential because a competent and promising company needs an efficient information system to communicate with its customers, supplies, and partners within the entire supply chain. In this research, a collaborative and event-driven supply chain information system (SCIS) is developed by using mobile object technology. The Unified Modeling Language (UML) is applied to analyze and design the SCIS Framework which contains two major components: information coordinator component (ICC) and agent component (AC). The ICC acts as the information integration manager. It manages all the ACs and establishes proper event channels for them to exchange information. Each member within the supply chain needs to possess an AC such that it can utilize the SCIS to exchange information with the other members. An application example is constructed and its corresponding system integration and testing procedure is demonstrated. From this demonstration result, it is believed that this SCIS framework provides a collaborative, event-driven, object-oriented, and agent-based infrastructure for the supply chain members to mutually exchange information efficiently.

A novel virtual metrology scheme for predicting machining precision of machine tools

Because virtual metrology (VM) can achieve real-time and on-line total inspection, it is a promising way for measuring machining precision of machine tools. However, the machining processes possess the characteristics of severe vibrations. Thus, how to effectively handle signals with low signal/noise ratios and extract key features from them is a challenging issue for successfully applying VM to the machine tools. In this paper, a novel VM scheme for predicting machining precision of machine tools is proposed based on several previously developed methods for data quality evaluation, model reliance evaluation, and machining precision prediction. Besides, for data preprocess, we propose a Wavelet-based de-noising method to improve the S/N ratio of sensor data. In addition, we base on the stepwise technique to develop an automatic feature selection method that can extract key features related to machining operations in time, frequency, and time-frequency domains, and can reduce the dimension of essential features. Testing results of a 3-axis CNC machine center machining standard workpieces show that the VMS can achieve the performance that the maximum average error of machining-precision conjecture is less than 2 um and the conjecture of 20 machining-precision items can be completed within 3.8 sec.

Development of an advanced manufacturing cloud for machine tool industry based on AVM technology

In this paper, a cloud manufacturing platform, called AMC (Advanced Manufacturing Cloud), is introduced. The AMC provides several manufacturing-related cloud services to facilitate the users to conduct supporting activities for machine tools and offers intelligent devices which can be plugged in various prediction models for performing predictive applications on machine tools. We first describe the architecture design of the AMC and then present methodologies to how to build cloud services and key mechanisms in the AMC. Finally, we construct a paradigm AMC and practically deploy its cloud services and intelligent devices in a public cloud platform and a factory of our cooperative machine tool company, respectively. We also conduct integrated tests to illustrate the efficacy and merits of the AMC.

Development of an AVM System Implementation Framework

Automatic virtual metrology (AVM) is the highest-level of technology for VM applications from the perspective of automation. It enables the fast application of VM to all pieces of equipment in a factory. The existing VM-related literature mainly focuses on creating VM models for manufacturing processes using different algorithms or methods and illustrating the defect-detection capability or the VM conjecture accuracy. Only a few of them mentioned how to implement the AVM system, but with limited details. This paper aims to present the development of an AVM system implementation framework (AVMSIF) to fill this gap. The proposed AVMSIF, together with the developed server-creation approach and XML-based system-operational mechanisms, can allow the complex AVM system to be created in a systematic and easy manner. Also, by adopting plug-and-play interfaces and desired functional modules, the AVMSIF can be applied to different types of equipment in the factory-wide VM deployment. According to the proposed AVMSIF, an AVM system has been successfully created and deployed in our cooperative thin-film-transistor-liquid-crystal-display (TFT-LCD) factory to confirm the effectiveness of the proposed AVMSIF. The results of this paper may be a useful reference for high-tech industries, such as semiconductor and TFT-LCD industries, in the construction of their AVM systems.

Application Cluster Service Scheme for Near-Zero-Downtime Services

The required reliability in applications of a distributed computer system is continuous service for 24 hours a day, 7 days a week. However, computer failures due to exhaustion of operating system resources, data corruption, numerical error accumulation, and so on, may interrupt services and cause significant losses. Hence, this work proposes an application cluster service (APCS) scheme. The proposed APCS provides both a failover scheme and a state recovery scheme for failure management. The failover scheme is designed mainly to automatically activate the backup application for replacing the failed application whenever it is sick or down. Meanwhile, the state recovery scheme is intended primarily to provide an inheritable design pattern to support applications with state recovery requirements. An application simply needs to inherit and implement this design pattern, and then can accomplish the task of state backup and recovery. Furthermore, a performance evaluator (PEV) that can detect performance degradation and predict time to failure is developed in this study. By using these detection and prediction capabilities, the APCS can perform the failover process before node breakdown. Thus, applying APCS and PEV can enable a distributed computer system to provide services with near-zero-downtime.

Development of Advanced Manufacturing Cloud of Things (AMCoT)—A Smart Manufacturing Platform

As semiconductor manufacturing processes are becoming more and more sophisticated, how to maintain their feasible production yield becomes an important issue. Also, how to build a smart manufacturing platform that can facilitate realizing smart factories is essential and desirable for current manufacturing industries. Aimed at addressing the above-mentioned two issues, in this letter, a five-stage approach for enhancing and assuring yield is proposed. Also, a smart manufacturing platform- Advanced Manufacturing Cloud of Things (AMCoT) based on Internet of Things, cloud computing, big data analytics, cyber-physical systems, and prediction technologies is designed and implemented to realize the proposed five-stage approach of yield enhancement and assurance. Finally, AMCoT is applied to a bumping process of a semiconductor company in Taiwan to conduct industrial case studies. Testing results demonstrate that AMCoT possesses capabilities of conducting total inspection in production, providing prognosis, and predictive maintenance on equipment, finding the root cause of yield loss, and storing and handling big production data, which as a whole is promising to achieve the goal of zero defects.

Industry 4.1 for Wheel Machining Automation

Industry 4.0 is set to be one of the new manufacturing objectives. The technologies involved to achieve Industry 4.0 are Internet of Things (IoT), cyber physical systems (CPS), and cloud manufacturing (CM). However, the current objectives defined by Industry 4.0 do not include zero defects; it only keeps the faith of achieving nearly zero-defects state. The purpose of this paper is to propose a platform denoted advanced manufacturing cloud of things (AMCoT) to not only achieve the objectives of Industry 4.0 but also accomplish the goal of zero defects by applying the technology of automatic virtual metrology (AVM). As such, by applying Industry 4.0 together with AVM to achieve the goal of zero defects, the era of Industry 4.1 is taking place. The application of wheel machining automation is adopted in this letter to illustrate how AMCoT and Industry 4.1 work.

Total precision inspection of machine tools with virtual metrology

The technology of virtual metrology (VM) has been applied in the semiconductor industry to convert sampling inspection with metrology delay into real time and online total inspection. The purpose of this study is trying to apply VM for inspecting machining precision of machine tools. However, machining processes will cause severe vibrations that make process data collection, data cleaning, and feature extraction difficult to handle. Thus, the tasks of how to accurately segment essential parts of the raw process data from the original numerical-control file, how to effectively handle raw process/sensor data with low signal-to-noise ratios, and how to properly extract significant features from the segmented and clean raw process data are challenging issues for successfully applying VM to machine tools. These issues are judiciously addressed and successfully resolved in this paper. Testing results of machining standard workpieces and cellphone shells of two three-axis CNC machines show that the proposed approach of applying VM to accomplish total precision inspection of machine tools is promising.