Yongjin Kwon

SMWA: A CAD-based decision support system for the efficient design of welding

Welding is one of the most widely used permanent joining technologies in assembly. As with other manufacturing processes, manufacturing feasibility and efficiency of weld components should be considered early in the part design stages to avoid costly redesign and delay. While there have been considerable research interests in weldability assessment and predictive modeling of welding distortion, under current practices, only after the part has been designed, welding engineers start working on the welding process plan. One significant reason for the current practice is the complexity involved in the decision and selection of feasible welding parameters. Therefore, there is a great need for a methodology that can incorporate benefits from Concurrent Engineering (CE) concepts into weld design. The objective of this study is to develop such a methodology to avoid welding infeasibility due to lack of manufacturability evaluations at the design stages and to generate a more complete and improved welding design in a shorter time. A CAD-based decision support system, named Sheet Metal Welding Advisor (SMWA), is developed for the purpose. The advantages include: (1) integration of CE concepts in welding design, thus improving the overall efficiency of design and manufacturing practices, (2) automatic generation of optimum welding parameters and associated manufacturing data for economic considerations, and (3) a great potential for the real-world applications.

Remote Control of Quality Using Ethernet Vision and Web-enabled Robotic System

A dynamic, globalized and customer driven market brings opportunities and threats to companies, depending on the response speed and production strategies. One strategy is concurrent engineering (CE) that focuses on improving the product development process, by the consideration of various factors associated with the life cycle of the product from the early stages. Design for manufacturing (DFM) has proven to be an effective approach to implement CE concept. Recently, an important DFM concept in product quality has drawn much attention from both academia and industry. This is because intense domestic and international competition has put more emphasis on quality. This study investigates the feasibility of integrating Ethernet-based vision system and assembly robot for the purpose of remote quality control. The accuracy and repeatability of the system were tested and verified over the Internet, prior to the quality inspection. The web-enabled quality check and robotic operations present many benefits, such as ubiquitous access, remote control/programming/monitoring capability, and integration of production equipment into information networks for improved efficiency and product quality within the framework of CE and DFM.

Internet Based Lab Framework Development for Distance Learning in Robotics and Mechatronics Education

A number of Internet-based educational tools have been developed to support mechanical education with Internet-based technologies. However, many of these tools have limitations as mostly just visual assistant tools for understanding engineering lectures. This paper describes lab framework development integrated with Internet-based robotics and mechatronics for mechanical education. The development efforts include advanced course and laboratory activities integrated with sensor networks and Internet-based technologies. The instructional materials for Internet-based robotics and automation education utilize Robotics and Mechatronics lab as the experiments of choice. The new Internet-based techniques allow the remotely situated students to program, control, and monitor the mechanical operations through the Internet. The architecture of the Internet-based lab focusing on remote data acquisition and measurement, as well as industrial control and automation applications, is illustrated. Implementation of a remote robotic vision feedback control lab is also described.Copyright

Network-based Vision Guidance of Robot for Remote Quality Control

A current trend for manufacturing industry is shorter product life cycle, remote monitoring/control/diagnosis, product miniaturization, high precision, zero-defect manufacturing and information-integrated distributed production systems for enhanced efficiency and product quality (Cohen, 1997; Bennis et al., 2005; Goldin et al., 1998; Goldin et al., 1999; Kwon et al., 2004). In tomorrow’s factory, design, manufacturing, quality, and business functions will be fully integrated with the information management network (SME, 2001; Center for Intelligent Maintenance Systems, 2005). This new paradigm is coined with the term, e-manufacturing. In short, ‘‘e-manufacturing is a system methodology that enables the manufacturing operations to successfully integrate with the functional objectives of an enterprise through the use of Internet, tether-free (wireless, web, etc.) and predictive technologies” (Koc et al., 2002; Lee, 2003). In fact, the US Integrated Circuit (IC) chip fabrication industries routinely perform remote maintenance and monitoring of production equipment installed in other countries (Iung, 2003; Rooks, 2003). For about the past decades, semiconductor manufacturing industry prognosticators have been predicting that larger wafers will eventually lead the wafer fabrication facilities to become fully automated and that the factories will be operated “lights out”, i.e., with no humans in the factory. Those predictions have now become a reality. Intel’s wafer fabrication facilities in Chandler, Arizona, USA, are now controlled remotely and humans only go inside the facility to fix the problems. All operators and supervisors now work in a control room, load/unload wafers 25

Performance characterization of precision micro robot using a machine vision system over the Internet for guaranteed positioning accuracy

There is a missing link between a virtual development environment (e.g., a CAD/CAM driven offline robotic programming) and production requirements of the actual robotic workcell. Simulated robot path planning and generation of pick-and-place coordinate points will not exactly coincide with the robot performance due to lack of consideration in variations in individual robot repeatability and thermal expansion of robot linkages. This is especially important when robots are controlled and programmed remotely (e.g., through Internet or Ethernet) since remote users have no physical contact with robotic systems. Using the current technology in Internet-based manufacturing that is limited to a web camera for live image transfer has been a significant challenge for the robot task performance. Consequently, the calibration and accuracy quantification of robot critical to precision assembly have to be performed on-site and the verification of robot positioning accuracy cannot be ascertained remotely. In worst case, the remote users have to assume the robot performance envelope provided by the manufacturers, which may causes a potentially serious hazard for system crash and damage to the parts and robot arms. Currently, there is no reliable methodology for remotely calibrating the robot performance. The objective of this research is, therefore, to advance the current state-of-the-art in Internet-based control and monitoring technology, with a specific aim in the accuracy calibration of micro precision robotic system for the development of a novel methodology utilizing Ethernet-based smart image sensors and other advanced precision sensory control network.