• Journal of the Korean Society for Precision Engineering
• /
• v.28 no.3
• /
• pp.315-322
• /
• 2011

High-accuracy micropatterns such as V-shaped microgrooves are increasingly in demand for various engineering areas. And the technical trend goes for large surface areas in precision machining technology. So micropatterns with large surface areas are expected to play an increasingly important role in today's manufacturing technology In this study, we focused on developing machining technologies. First, a machine vision system for precise tool setting is developed. Second, an on-machine measurement (OMM) system for large-area measurement is implemented. And also software for tool path generation and simulation is developed. With these technologies we fabricated large-surface micropatterns in an electroless nickel-plated workpiece with single-crystal diamond tools and a 32-in, $675mm{\times}450mm$ mold with tens of V-and pyramid-shaped micropatterns.

• Journal of the Korean Society for Precision Engineering
• /
• v.25 no.8
• /
• pp.21-28
• /
• 2008

Fizeau interferometer is used for inspecting the lens surface profile accurately. This study is focused on the design and optical measuring techniques for large optical components, such as a reflection mirror for large area lithography or astronomical purpose. A tower type Fizeau interferometer is designed and set up in horizontally with a 45$^{\circ}$ fold mirror which makes easy to align the optical path of heavy interferometer system. To align the optical path, a five-axes stage for the interferometer is required. This study shows a method of the 45$^{\circ}$ fold mirror alignment by using a three-axis stage instead of adjusting the interferometer itself or measuring object. This system will be installed on the large optics polishing machine during the manufacturing process as an on-machine inspection system.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.05a
• /
• pp.287-292
• /
• 2002

This paper presents a reverse engineering method for compound surfaces using vision system. A CNC machining center is used as a measuring station, which is equipped with slit beam generator and vision probe. Since obtained data using slit beam or laser scanner may have much data loss along the edge of compound surfaces, an algorithm is presented in this study to recover missing geometric data at such region. First, b-spline interpolation is applied to extract edge information of the surface, and as a next step, b-spline approximation is applied to recover the missing geometric data. Finally, b-spline skinning method is applied to regenerate the surface information. Appropriate simulation and experimental works are preformed to very the effectiveness of the proposed methods.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.36 no.2
• /
• pp.195-201
• /
• 2012

According to many customers' requests, optical measurement module (OMM) applications using automatic measuring devices to measure the machined part rapidly on a machine tool have increased steeply. Touch trigger probes are being used for job setup and feature inspection as automatic measuring devices, and this makes quality checking and machining compensation possible. Therefore, in this study, the use of touch trigger probes for accurate measurement of the machined part has been studied and a macro program for a hole measuring cycle has been developed. This hole is the most common feature to be measured, but conventional methods are still not free from measuring error. In addition, the eccentricity change of the least square circle was simulated according to the roundness error in a hole measurement. To evaluate the reliability of this study, the developed hole-measuring program was executed to measure the hole plate on the machine and verify the roundness error in the eccentricity simulation result.