Hyun Joong Yoon

Multi-agent-based scheduling methods for hybrid cellular production lines in semiconductor industry

This article addresses scheduling problems for the hybrid cellular production lines in the semiconductor industry, in which the hybrid cellular production line is defined as the production system composed of both single-functional and multi-functional cellular layouts. Detailed system configuration and material flow of a hybrid cellular production line are presented, and then, the scheduling problems in the hybrid cellular production line are separated into an inter-cell scheduling problem and intra-cell scheduling problems. A multi-agent-based scheduling method is proposed for the inter-cell scheduling problem, and a real-time heuristic scheduling method is proposed for the intra-cell scheduling problem. In the simulation experiments, various scenarios have been compared under the proposed inter-cell and intra-cell scheduling methods with the hybrid cellular production line composed of six cells.

Simulation Software for Semiconductor Photolithography Equipment: TrackSim

This paper describes the development of the TrackSim, which is a discrete event simulation tool for photolithography equipment of semiconductor industry. The TrackSim is focused on the accurate simulation model of the photolithography equipment and easy-to-use user interfaces. TrackSim provides 3D simulation environment for evaluating, validating, and scheduling the photolithography process. One of the major characteristics of TrackSim is in that it is developed based on Applied Materials` AutoMod, a discrete event simulation software broadly used in semiconductor industry. Accordingly, the photolithography model of TrackSim can be used to perform simulation connected with other simulation models built with AutoMod.

Teleoperation Using Reconstructed Graphic Model

In typical master/slave teleoperation systems, a human operator generally manipulates the master to control the slave through the visual information like camera image. However, the operator may get into trouble due to the limited visual information depending on the camera positions and the delay on the visual information because of low communication bandwidth. To cope with this inherit problem in the camera-based teleoperation system, this paper presents a teleoperation system using a reconstructed graphic model instead of the camera image. The proposed teleoperation system consists of a robot control module, a master module using a force-reflective joystick, and a graphic user interface (GUI) module. The graphic user interface module provides the operator with a 3D model reconstructed using a small set of sensing data received from the remote site. The proposed teleoperation system is evaluated through a peg-in-hole assembly task.