자동차 타이어 모델의 곡면 모델링 및 5축 NC 가공

이철수,Lee, Cheol-Soo 대한산업공학회 1996 산업공학 Vol.9 No.2

Recently, the tire mold of a passenger car is made almost via aluminum casting, and it is necessary to prepare a master model of the tire for the casting. Because of the geometrical feature of tire, as well known, the master model must be machined by a 5-axis NC machine. The paper proposes a procedure to model and machine the master model. The approach includes (a) transformation of 2D drawing of tire into 3D geometry, (b) modeling surfaces of tire, and (c) inverse kinematics of a 5-axis NC machine. An implementation of the proposed procedure is also presented.

상호 결합을 이용한 광대역 E-면 H 섹터 혼 위상 배열 안테나 설계

이철수,백정기,Lee, Cheol-Soo,Pack, Jeong-Ki 한국전자파학회 2007 한국전자파학회논문지 Vol.18 No.6

H 섹터 혼 안테나는 일정한 빔 커버리지를 가지면서 빔 조향을 하는 광대역 위상 배열 송신기의 복사 소자로 유용하다. 본 논문에서는 상호 결합을 이용하여 3:1 주파수 대역과 ${\pm}60^{\circ}$의 빔 조향 범위를 갖는 광대역 E-면 H 섹터 혼 위상 배열 안테나를 설계하였다. 주자계면에서 반전력 빔 폭이 $30{\sim}50^{\circ}$을 갖는 H 섹터 혼 안테나를 설계하였다. 도파관 시뮬레이터를 이용하여 상호 결합을 포함하는 능동 반사 계수를 계산하였고, 광대역 주파수 범위에서 상호 결합에 의하여 능동 반사 특성이 개선되었다. 이러한 결과를 이용하여 $8{\times}1$ H 섹터 혼 위상 배열안테나를 제작하였다. 주자계면에서의 반전력 빔 폭과 능동 반사 계수의 측정 결과는 시뮬레이션 결과와 잘 일치하였다. 빔 조향된 복사 빔들의 첨두치 패턴은 능동 소자 패턴과 잘 일치하였다. 3:1 주파수 대역과 빔 조향 범위에서 능동 반사 계수는 대부분 0.3 이하로 측정되었다. An H-sector horn antenna has a constant beam coverage characteristic and it can be useful for application to a wide band phased array antenna system. In this paper, we designed a broadband E-plane H-sector horn phased-array antenna, which has a 3:1 bandwidth and ${\pm}60^{\circ}$ beam steering capability. An H-sector hem antenna was designed to have $30{\sim}50^{\circ}$ half-power beam width in the principal H-plane. The active reflection coefficient including mutual coupling was calculated using a waveguide simulator, and the active reflection characteristic was improved by mutual coupling over wide frequency range. Using these results, an $8{\times}1$ H-sector phased array antenna was fabricated. The measurement results for the half-power beam width in the principal H-plane and the active reflection coefficient showed a good agreement with the simulation results. The peak-value pattern in the steered radiation beams also agreed well with the active element pattern. The measured active reflection coefficients within the beam steering range are mostly less than 0.3 over the 3:1 frequency range.

컴퓨터 비젼에 의한 PCB 검사를 위한 검사 정보 생성 시스템 개발

이철수,고은희,Lee, Cheol-Soo,Go, Eun-Hee 대한산업공학회 1998 산업공학 Vol.11 No.2

For the PCB inspection by computer vision, in some cases, the MRLC file should prepared. The MRLC file contains a RLC(Run Length Code) and a direction flag. In this paper, a generating method of MRLC is described. It is composed of two procedure as followings; (i) rasterizing Gerber file which is a vectorized image of PCB panel, and (ii) calculating a MRLC that is useful for the inspection as a template image. The suggested procedures are written in C-language and executable on Windows 95 and Windows NT.

선박용 플랫바의 자동 네스팅 및 가스/플라즈마에 의한 NC 절단

이철수,박광렬,Lee, Cheol-Soo,Park, Gwang-R. 대한산업공학회 1996 산업공학 Vol.9 No.3

The 'flat-bar' is a stiffener which is a component of ships. It is basically a long rectangle and has 'end-cut' shapes at both sides. The paper describes a fast nesting algorithm of the flat-bar, and a procedure to generate cutting path of gas/plasma torch, which is operated by a NC (numerically controlled) gas/plasma cutting machine. Proposed procedures are written in C-language and executable on VAX machine with Open VMS operating system.

피스톤의 형상 모델링 및 CNC 가공 데이터 산출용 소프트웨어 개발

이철수,이제필,김성복,Lee, Cheol-Soo,Lee, Je-Phil,Kim, Seong-Bok 대한산업공학회 1999 산업공학 Vol.12 No.1

A noncircular cutting such as a piston cutting has depended on the copy-machining because of its complex shape. But the copy-machining needs a master model and brings about a low quality of the piston caused by being worn out of the master model. And the lower cutting speed reduces the productivity. In this paper, for solving these problems, a specialized software system and its subsequent procedure are presented. The shape of a piston consists of an oval, an offset, recesses, and eccentricities. The paper describes these shapes as a consistent equation that is a function of the rotational angle and the position of longitudinal direction(Z-axis). It is simple to define the characteristic geometry of a piston and to generate a tool path for CNC machining. This paper proposes the a proper structure of a 4-axes CNC(Computerized Numerical Control) lathe for machining the piston. As well as X-axis and Z-axis, are attached to the machine a C-axis for rotation and a Y-axis for higher speedy prismatic motion parallel to X-axis.

타이어 사이드판의 문자 가공을 위한 4축 가공 시스템

이철수,박광렬,Lee, Cheol-Soo,Park, Gwang-Ryeol 대한산업공학회 1998 산업공학 Vol.11 No.2

The letters of the automobile tire are usually engraved on the side-wall. The shape of the side-wall is a sculptured surface generated by the rotational sweeping of a profile curve. The letters laid on the side-wall are usually designed by a 2-dimensional CAD. It is impossible to machine the letters on the surface accurately by 3-axis NC machining, because the axis of cutter should be tilted to align with the normal vector of the surface. In this case. the degree of freedom for the machine is at least four. This paper describes an idea for tool path generation of a 4-axis machine by using the 2-dimensional CAD data of the letters and the surface of the side-wall. This study includes the following procedures; (1) measuring the profile of the side-wall surface and curve-fitting of the measured points. (2) the 'non-parallel projection' of the letters on the side-wall, and (3) an inverse kinematics of the 4-axis lettering machine. Procedures in this paper are programmed in C-language on Windows95 environment. With a PC based CNC controller and a 4-axis lettering machine. these are tested sucessfully for the practical use.

조선 블록 운반용 Lug 배치 자동화 시스템

이철수(Cheol Soo Lee),이재현(Jae Hyun Lee),심주현(Ju Hyun Shim),허은영(Eun Young Heo),김종민(Jong Min Kim) (사)한국CDE학회 2012 한국 CAD/CAM 학회 학술발표회 논문집 Vol.2012 No.2

실시간 제어에 의한 개방형 CNC 소프트웨어 모듈의 설계 및 구현

이철수(Cheol-Soo Lee),이제필(Je-Phil Lee) 한국공작기계학회 1999 한국공작기계학회지 Vol.8 No.5

This paper describes the design and implementation of a PC(personal computer) based open architecture machine tool controller. The hardware of open architecture CNC has generally a motion control board on a PC for controlling a servo motor. But this paper describes open architecture hardware that consists of a PC, a counter board, a DAC board, and a DIO board only. This makes it easy to generate CNC software module in a hardware-independent way. The proposed open architecture CNC software runs on the MS-Windows NT. The paper describes a method of con-trolling servo motors using a real-time timer of MS-Windows NT and a commercial real-time operating system on the MS-Windows NT. An open and reconfigurable software module is made up of an object and an API(application programming interface). Using the object and the API, a new CNC system can be quickly configured to control different machine tools. The proposed open architecture CNC system is applied to 4-axis lettering center.

통상임금 관련 2013년 전원합의체 판결의 의미와 평가

이철수(Lee, Cheol-Soo) 한국노동법학회 2014 노동법학 Vol.0 No.49

In its two recent decisions on Dec 8, 2013 (2013. 12. 18. 2012DA89399, and 2013.12.18. 2012DA94643), the Korean Supreme Court has set out detailed standards on the previously contested regular wage rate, and it also set out the standards for when the worker"s request for additional payment is void as against the principle of good faith in civil law. As for the first part of the court decision - ‘periodicity’ and ‘consistency’ element of the regular wage rate - the court has maintained its previous rulings on this topic. Meanwhile, as for the ‘fixedness’ element of the regular wage rate, the decision mentioned that “determining fixedness in advance” is the pivotal standard; thereby overcoming the rigidity in its previous discussions. However, it is problematic that this decision has also mentioned that when a working requirement is attached, fixedness element may not be found in such circumstances; this part may fuel labor-employment conflict in the future. This article criticizes this part, arguing that working requirement fits in the consistency element, and even when the worker resigns during the term of employment, it should not affect the worker"s regular wage rate. This article also suggests that the court should not have resorted to the principle of good faith; there are both legal and factual reasons why it should not be that way, and the author suggests alternative ways of applying the principle.

Micro-EDM 가공에서 Micro-Spot 이용한 표면 형상의 예측 모델에 관한 연구

이철수(Cheol Soo Lee),김종민(Jong Min Kim),허은영(Eun Young Heo),김동수(Dong Soo Kim) (사)한국CDE학회 2011 한국 CAD/CAM 학회 학술발표회 논문집 Vol.2011 No.1

Recently with increased demand of micro mechanical and electronic devices, interests are focused on machining of micro parts. Accordingly, a lot of researches have been progressed for fabrication or micro parts using MMT (Micro Machining Technology) or MEMS (Micro Electromechanical System), etc. and concerned machining technologies. As Micro Machining Technology (MMT) has low production cost and is able to overcome limit of the materials, it has very important position over MEMS technology. Metal forming in micro unit has been suggested in various methods for a long time and a lot of related data has been accumulated. However, the existing machines such as micro lathe, micro milling or micro drilling, etc. have factors to be overcome to allow machining in micro unit precision. In order to overcome these machining problems, a lot of researches on machining such as micro channel or hole, etc. using complex machining technique, Micro EDM, rather than the existing methods have been being progressed. This study intents to measure shape of surface for micro discharging machining using micro spot that is a unit machining of micro discharging machining and surface shape from micro discharging using it.