Proceedings of the 2005 Winter Simulation Conference M. E. Kuhl, N. M. Steiger, F. B. Armstrong, and J. A. Joines, eds. ABSTRACT Reconfigurability of machine tools is one of the critical factors to realize the responsive manufacturing systems to satisfy the mass-customization production. This paper presents the methods to model and simulate the machine tools on Internet in response to change in the machining requirements. Specifically, a set of module combination rules and a modeling method of the structure of machine tools using connectivity graph are developed. In response to the user requirements, kinematic relations and struc- tures of machine tools can be derived using the module combination rules and connectivity graph relationships. Internet-based simulator of machine tools is implemented and presented. The developed machine tool simulator can be used to verify the structure of machine tools derived from the user requirements. 1 INTRODUCTION Under the mass-customization paradigm which requires flexibility to produce the variety of products as well as the volume responsiveness, design of modular machine tools are necessary (Mehrabi, Ulsoy, and Koren 2000; http://www.opengl.org; http://erc.engin. umich.edu). To increase the responsiveness of machine tools to the required production volume and product vari- ety, it is useful to model and simulate the changed func- tionality of machine tools through Internet.. This research is to present the method to model and simulate the struc- ture of machine tools in response to the required changes. Since the structure of machine tools has close rela- tions with the other properties of machine tools, machine tools are designed based on their structures (Koenigsber- ger and Tlusty 1970). Vragov presents the notation to rep- resent the machine tools using logic operation and multi- ple-factor theory (Vragov and Yu 1972). Shinno and Ito develop a series of methods to generate the structure of machine tools through introduction of modular compo- nents of machine tools (Shinno and Ito 1984, Shinno and Ito 1986). Kitajima and Yoshikawa (1984) propose a structure model to relate the components of machine tools in hierarchy, and develop a designing system of machine tools using the proposed method. Chaar et al.(1998) pre- sent the relational model to decompose and combining the module components of machine tools in a virtual envi- ronment and implement their model to develop commer- cial simulation software, ADAMS (Chaar et al. 1998). Ehmann et al.(1997) at MT-AMRI pointed out that simu- lation of machine tools is necessary to minimize the trial errors to design and implement the machine tools and pre- sent the framework of virtual machine tools (Ehmann et al. 1997). Suh et al. (2003) propose the web-based ma- chine tool (WVMT) to model and simulate machining centers on Internet. Seo et al. (2005) develop a web-based CAM system to dynamically show the machining process on user’s applet through Internet. In this paper, we propose structure modeling method STRUCTURE MODELING OF MACHINE TOOLS AND INTERNET-BASED IMPLEMENTATION Yoonho Seo Dong-Pyo Hong Insu Kim Dept. of Industrial Systems & Information Engineering Korea University Anamdong #1, Sungbukgu Seoul 136-713, KOREA Taioun Kim Department of Industrial Engineering Kyungsung University Daeyondong, Namgu Busan 314-79, KOREA Donmok Sheen Dept. of Transportation Systems Engineering University of Ulsan Moogurdong san#29, Namku Ulsan 680-749, KOREA Gyu-Bong Lee KITECH, Hongcheonri 35-3, Ibjangmyun Cheonan 330-825, KOREA 1699