• International Journal of Reliability and Applications
• /
• 제9권1호
• /
• pp.7-15
• /
• 2008

The dimensional measurement equipment, such as Coordinate Measurement Machine (CMM), Optical Coordinate Measurement Machine (OCMM), and Checking Fixture (CF), take multiple dimensional measurements for each part in an automobile industry. Measurements are also recorded under different measurement systems to see if the responses differ significantly over these systems. Each measurement system (CMM, OCMM, and CF) will be considered as different treatments. This set-up provides massive amounts of process data which are multivariate in nature. Therefore, the multivariate statistical analysis is required to analyze data that are dependent on each other. This research provides step by step methodology for the evaluation procedure of the compatibility of measurement systems and clarify a systematic analyzation among the different measurement system's compatibility followed by number of case studies for each methodologies provided.

• 한국기계기술학회지
• /
• 제13권4호
• /
• pp.131-136
• /
• 2011

In commercial vehicle, sub-frame which equipped in main frame supporting dump deck and oil tanker. This is the main structure for all equipment which including joint function. Sub-frame is made by welding process, this susceptible to deform and crack by its longitudinal size. Also various kind of sub-frame make it difficult to standardization in manufacturing process and exclusive jig is not adapted yet. Frame size is over 6~8m and weight is more than 300kg this make re-work more difficult. If manufacturing company made precise sub-frame, this is not only convenient for customers but also save the company money by reducing the working time. In this study manufacture the sub-frame be suitable for its main function and develop exclusive welding jig for obtain checking fixture function as well.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2002년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
• /
• pp.96-98
• /
• 2002

This paper proposes the digital pin line checker which can extremely improve the efficiency of the pine line checking using a micro processor. The line checker is designed which can check efficiently up to maximum 2048 pin. Alarm busser is designed ringing real-timely the case that the pin line is connected differently with real node number. Accordingly the comparing and identifying work visually the node number showing on the displaying board with real node number is avoided after the electronic stimulus enforce to the pin of the fixture by the test engineer. The digital line checker is designed based on the 8051. And the effectiveness and accuracy of the proposed line checking strategy is tested by simulating the several error connections for pin lines on the small scale board.

• 한국기계가공학회지
• /
• 제10권4호
• /
• pp.50-56
• /
• 2011

Injection molding process is one of the popular manufacturing methods to produce plastic parts with high efficiency and low cost. Ball seat for automobile suspension is made by an injection molding process as a part to support pivot function of ball joint consisted of ball stud and housing. It is necessary for a ball seat to have a dimensional stability in the three dimensional inner area to be contacted with ball stud. In this paper, the dimensional stability of inner surface is indirectly analyzed by checking the difference of inner diameter around the circumferential direction and the thickness variation at the top part of ball seat. Measurement was performed by using the coordinate measuring machine and the fixture to hold ball seat. Optimization of injection molding processes such as injection time, cooling time and temperatures of cylinder barrel was derived to reduce the difference of inner diameter and the thickness variation at the top part of ball seat based on the Taguchi method.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2001년도 추계학술대회논문집A
• /
• pp.521-526
• /
• 2001

This research develops a low-cost and high accurate kinematic calibration method for a parallel typed machining center tool. A planar table is used for a mechanical fixture restricting the platform to place at the constrained pose and a low-cost and high accurate digital indicator is employed for a device checking if the constrained movement is satisfied within the established range. The kinematic parameters calibrated with respect to a single plane aren't influenced from the misalignment of the plane. A parameter observability is successfully obtained even through one planar constraint, which guarantees that the kinematic parameters is estimated by minimizing the cost function.

• 유공압시스템학회논문집
• /
• 제8권3호
• /
• pp.14-20
• /
• 2011

This study aims at aligning multiple wafers to reduce wafer handling time in wafer processes. We designed a multilevel structure for a prealigner which can handle multiple wafer simultaneously in a system. The system consists of gripping parts, kinematic parts, vacuum chucks, pneumatic units, hall sensors and a DSP controller. Aligning procedure has two steps: mechanical gripping and notch finding. In the first step, a wafer is aligned in XY directions using 4-point mechanical contact. The rotational error can be found by detecting a signal in a notch using hall sensors. A dual prealigner was designed for 300mm wafers and constructed for a performance test. The accuracy was monitored by checking the movement of a notch in a machine vision. The result shows that the dual prealigner has enough performance as commercial products.

• International Journal of Reliability and Applications
• /
• 제9권1호
• /
• pp.17-30
• /
• 2008

Analysis of measurement systems is important to determine if the measurement process is adequate to measure the part-to-part variability in the process. Control chart techniques provide an effective, and easy-to-use method for performing this analysis. However, application with the real data for the evaluation procedure for multiple measurement systems have not been demonstrated. This research will provide a methodology for the evaluation of part-to-part variation and variation of different measurement systems step by step followed by number of case studies for each methodologies provided.

• 한국시뮬레이션학회논문지
• /
• 제15권1호
• /
• pp.51-58
• /
• 2006

가상생산은 새로운 제품의 개발, 새로운 설비의 개발, 새로운 생산시스템의 개발에 활용할 수 있는 매우 유용한 기술이다. 이 기술을 사용하면 실제 생산활동이 수행되기 이전에 다양한 설계오류를 수정할 수 있다. 본 논문은 가상생산기술을 굴삭기 생산공정에 적용한 사례다. 굴삭기 상부 부품의 하나인 붐과 상판회전체의 최종 용접공정을 연구의 대상으로 선택하였다. CATIA를 이용하여 각 부품의 3D 모델과 치구의 3D 모델을 개발하였으며, IGRIP을 이용하여 용접공정의 3D 시뮬레이션 모델을 개발하였다. 이러한 3D 모델들을 치구의 설계검증과 로봇시스템의 동작경로 검증등에 활용하였다. 결과적으로 수동 용접공정을 로봇을 이용한 자동용접공정으로 전환하였으며, 그 과정에서 설계오류에 의해 발생하는 재 작업시간과 비용을 감축시켰다.