• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.766-770
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• 1996

In this study, a CAD/CAM system for axisymmetric deep drawing processes has been developed. An approach to the system is based on the knowledge based system. Under the environment of CAD/CAM software of Personal Designer, the system has been written in UPL. The geometries of intermediate and final object in deep drawing process, including processes parameters are input for the CAD/CAM system. The input data can be obtained from the results of Pro-Deep. The parts drawing of die sets for each process is generatedin tool design module of the CAD/CAM system. Also, the die assemblydrawings can be obtained. NC commands for machining of the part can be generated in the developed CAD/CAM system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1992.10a
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• pp.47-51
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• 1992

Automatic detection of tool breakage during NC machining is a key issue not only for improving productivity but to implement the unattended manufacturing system. In this paper, we develop a vibration sensor-based tool breakage detection system for NC milling processes. The system obtains the time-domain vibration signal from the sensor attached on the spindle bracket of our CNC machine and declares tool failures through the on-line monitoring schemes. For on-line detection, our approach is to use the PSC(statistical process control) methods being increasingly used for on-line process control. The main thrust of this paper is to propose and compare the performance of SPC methods including : a) X-bar control scheme, b) S control scheme, c)EWMA (exponentially weighted moving average) scheme, and d) AEWMA (adaptive exponentially weighted moving average) scheme. The performance of the control schemes are compared in terms of the type 1 and 2 error calculated from the experiment data.

• Korean Journal of Computational Design and Engineering
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• v.4 no.1
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• pp.52-59
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• 1999

The CAD/CAM System for deep drawing transfer die tin mechanical press process has been developed. The developed CAD system can generate the drawing of transfer die in mechanical press. Using thee results from CAD system, it can generate the NC data to machine die's elements on the CAD system. This system can reduce design man-hour an human errors. In order to construct the system, it is used to automated the design process and generate the NC data using concepts of the designing rule and the machining rule. The developed system is based on the knowledge base system which is involved a lot of expert's technology in the practice field. Using AutoLISP language under the AutoCAD system, CTK customer language of SmartCAM is used as the overall CAD/CAM environment. Results of this system will be provide effective aids to the designer and manufacturer in this field.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.4
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• pp.79-86
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• 2002

As consumer electronics, information, and aero-space industry grow, the demand for aspheric lens increases higher. To enhance the precision and productivity of aspheric surface, a CAM system for ultra-precision aspheric surface needs to be realized. In this study, the developed CAM system can generate NC code fur various aspheric surfaces fast and precisely by a new bi-arc interpolation method that the location of maximum error is fixed at an efficient point. The newly developed bi-arc meets the given tolerance more precisely, performs faster calculation. The cutting condition input module and the NC code verification module are adequate to ultra-precision machining, so that a operator can obtain products fast and easily.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.6
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• pp.1361-1371
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• 1993

The effort of this paper is to develop a methodology of computer aided design and manufacture of spatial cams. The integrated CAD/CAM systems for spatial cams are developed to enable manufacturer to design and machine them readily. The contour of spatial cams can be obtained by applying envelope theory to the cam/follower motion. The mathematical cam contour is evaluated at some increment to generate the numerical data for the CNC programming. Incremental generation of points along a cam contour can be accomplished in consideration with the specified tolerance. The computerized procedure is described in detail with accompanying examples.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.05a
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• pp.793-796
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• 2005

금형공장의 생산 일정관리에 있어서 실제 가공작업에 대한 실적데이터의 집계는 매우 중요하지만, 이러한 작업상황을 기록하는 것에 대해서 현장 작업자는 비협조적이고 반감을 갖고 있는 실정이다. 현장에서는 작업자의 개입없이 CNC 장비의 컨트롤러와의 직접적인 인터페이스를 통해서 신호를 추출하고 자동으로 작업상황을 파악할 수 있는 시스템을 구축하려고 시도하고 있지만, 컨트롤러 메이커마다 다르게 적용해야 하고 많은 비용을 요구한다. 이러한 이유로 본 연구에서는 저가의 PC 카메라를 장비에 설치하여 가공상황에 대한 동영상을 수집하고 영상처리 알고리즘을 적용하여 가공시간을 집계하는 방법을 제안한다. 제안된 방법은 CNC 컨트롤러에 독립적으로 운용되며 저렴하게 시스템을 구축할 수 있는 장점이 있다. 본 연구에서는 무인가공과 유인가공 상황에 시범적으로 적용 및 운영함으로써 시스템의 활용가능성을 살펴보았다.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1998.06b
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• pp.1-7
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• 1998

본 연구에서는 3차원 솔리드 모델러로부터 Modeling한 후 제작된 model 에 사용자가 원하는 측정 위치를 지정함으로써 자동적으로 측정용 NC Data를 얻을 수 있는 알고리즘을 설계하고 이를 Program화하였다. 3-D Modeler로서 Unigraphics를 사용하였으며, 공작기계는 FANUC Controller를 장착한 Machining Center이다. 측정용 센서는 접촉식 Probe를 사용하였다. 본 연구를 통하여 CAD시스템에서 구축된 Geomaatric Model로부터 직접 측정을 위한 NC data를 얻고 이 data를 가공후의 측정 Data와 비교하여 봄으로써 제품의 가공정밀도를 확인해 볼 수 있으며, 가공시의 간섭 check, 잔삭가공여유, 과절삭등 다양한 정보를 얻을 수 있을 것이다. 향수 지속적인 연구개발을 통하여 data의 통계처리 및 공작기계의 오차 보정등을 고려하여 줌으로써 기계상에서의 측정 data에 대한 신뢰도를 구축할 수 있을 것으로 사료된다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.534-537
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• 1996

As consumer electronics, information, and aero-space industry grow, the demand for aspheric lens increases higher. To enhance the precision and productivity of aspheric surface, a CAM system for ultra-precision aspheric surface needs to be realized. In this study, the developed CAM system can generate NC code for various aspheric surfaces fast and precisely by Tri-arc interpolation method that the location of maximum error is fixed. The cutting condition input module and the NC code verification module are adequate to ultra-precision machining, so that a operator can obtain products fast and easily.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.3
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• pp.61-67
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• 1998

Rapid prototyping becomes widely used in design and manufacturing of mechanical and aerospace engineering. Here a drag valve disk consisted of complicate configuration has designed by CAD, and prototyped by a stereolithography apparatus (SLA) to confirm the design configuration. Also the prototyped valve disk was used for checking if it could be applied for casting from the view point of accuracy, cost, and time. The rapid-prototyped disk by SLA was compared with a high-speed machined disk by MAKINO V55, and it is found that the prototyping of the disk by SLA appears more economical, more accurate and faster than by machining with MAKINO V55.

• Korean Journal of Computational Design and Engineering
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• v.13 no.2
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• pp.153-161
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• 2008

This paper proposes an efficient algorithm for deriving inverse kinematics equation of 5-axis machine. Because the joint order and direction of 5-axis machine are different for each type of machine, each type of machine needs its own inverse kinematics equation for post-processing of NC data. Also derived inverse kinematics equation may cause problems of indeterminate and inconsistent solution. In order to resolve these problems, we have developed a generic method to derive direct kinematics equation by considering orthogonal joints of 5-axis machines. Using this method, we also have proposed a general algorithm for deriving inverse kinematics equation for various types of 5-axis machines.