• 대한산업공학회지
• /
• 제21권1호
• /
• pp.137-151
• /
• 1995

A difficult problem in operating Flexible Manufacturing Systems (FMS) is to control the system in real-time by coordinating heterogeneous machines and integrating distributed information. The objective of the paper is to present the models and methodologies useful to resolve the difficult problem. The detailed objectives can be described in three folds. First, a hierarchical Colored and Timed Petri-Net (CTPN) is designed to control an FMS in real-time. The concerned FMS consists of a loading station, several machining cells, a material handling system, and an unloading station. Timed-transitions are used to represent the timed-events such as AGV movements between stations and cells, part machining activities in the cells. Signal places are also used to represent communication status between the host and the cell controllers. To resolve the event conflicts and scheduling problems, dispatching rules are introduced and applied. Second, an implementation methodology used to monitor and diagnose the errors occurring on the machines during system operation is proposed. Third, a Petri-Net simulator is developed to experiment with the designed control logic.

• 제어로봇시스템학회논문지
• /
• 제5권6호
• /
• pp.724-733
• /
• 1999

An effective method of system modeling and dynamic scheduling for the back-end line of semiconductor manufacturing is proposed. The virtual factory, describing semiconductor manufacturing line, is designed in detail, and then a Petri net model simulator is developed for operation and control of the modular cells of the virtual factory. The petri net model is a colored timed Petri nets (CTPNs). The simulator will be utilized to analyze and evaluate various dynamic status and operatons of manufacturing environments. The dynamic schedulaer has a hierarchical structure with the higher for planning level and the lower for dynamic scheduling level. The genetic algorithm is applied to extract optimal conditions of the scheduling algorithm. The proposed dynamic scheduling is able to realize the semiconductor manufacturing environments for the diversity of products, the variety of orders by many customers, the flexibility of order change by changing market conditions, the complexity of manufacturing processes, and the uncertainty of manufacturing resources. The proposed method of dynamic scheduling is more effective and useful in dealing with such recent pressing requirements including on-time delivery, quick response, and flexibility.

• ETRI Journal
• /
• 제40권4호
• /
• pp.483-498
• /
• 2018

Nowadays, with progresses in robotic science, the design and implementation of a mechanism for human-robot interaction with a low workload is inevitable. One notable challenge in this field is the interaction between a single human and a group of robots. Therefore, we propose a new comprehensive framework for single-human multiple-robot remote interaction that can form an efficient intelligent adaptive interaction (IAI). Our interaction system can thoroughly adapt itself to changes in interaction context and user states. Some advantages of our devised IAI framework are lower workload, higher level of situation awareness, and efficient interaction. In this paper, we introduce a new IAI architecture as our comprehensive mechanism. In order to practically examine the architecture, we implemented our proposed IAI to control a group of unmanned aerial vehicles (UAVs) under different scenarios. The results show that our devised IAI framework can effectively reduce human workload and the level of situation awareness, and concurrently foster the mission completion percentage of the UAVs.