• 한국염색가공학회지
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• 제35권2호
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• pp.121-127
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• 2023

In this study, a comprehensive investigation was conducted on the morphological and property changes of laser-induced nanocarbon (LINC) as a function of laser process parameters. LINC was formed on the surfaces of polyimide films with different backbone structures under various process conditions, including laser power, scan speed, and resolution. Three different forms of LINC electrodes (i.e., continuous 3D porous graphene, wooly nanocarbon fibers, line cut) were formed depending on the laser power and scan speed. Furthermore, heteroatom doping induced from the chemical structure of the polyimide during laser patterning was found to be effective in modifying the electrical properties of LINC electrodes. The LINC surfaces exhibited different microstructures depending on the laser beam resolution under constant laser power and scan speed, allowing for controllable surface wettability. The correlation between the chemical structure of the polymer substrate, laser process parameters, and carbonized surface properties in this study is expected to be utilized as fundamental understanding for the manufacturing of next-generation carbon-based electronic devices.

• 한국정밀공학회지
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• 제27권10호
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• pp.14-22
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• 2010

The most costly and time-consuming process in the fabrication of today's multi-layer circuit board is drilling interconnection holes between adjacent layers and via holes within a layer. Decreasing size of via holes being demanded and growing number of via holes per panel increase drilling costs. Component density and electronic functionality of today's multi-layer circuit boards can be improved with the introduction of cost-effective, variable depth laser drilled blind micro via holes, and interconnection holes. Laser technology is being quickly adopted into the circuit board industry but can be accelerated with the introduction of a true production laser drilling system. In order to get optimized condition for drilling to FPCB (Flexible Printed Circuit Board), we use various drill pattern as drill step. For productivity, we investigate drill path optimization method. And for the precise drilling the thermal drift of scanner and temperature change of scan system are tested.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1994년도 추계학술대회 논문집
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• pp.55-60
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• 1994

최근의 사무기기용 다면체반사경을 비롯하여 메모리 디스크,복사기용 드럼등은 물론 레이저 응용, X-선용의 천체망원경 및 현미경등의 광기술에 "초정밀 가공기술"의 용도가 점차 확대되어 가고 있는데, 이는 진보된 과학과 공업기술에 대한 시스템에 있어서 광학, 전기 및 전자 그리고 기계 부품의 생산에 가장 중요한 핵심기술의 하나이다. 본 연구에서는 초정밀 전용 공작기계가 아닌 범용 CNC 선반에 초정밀 절삭공구인 직선 절인의 천연다이아몬드 공구와 공작물로써 알루미늄합금을 장착하고, 선삭하여 초정밀 절삭에 관한 정성적인 데이터를 얻고자, 절삭조건에 따른 표면거칠와 절삭력 등의 변화를 조사하였다.변화를 조사하였다.

• 한국기계가공학회지
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• 제13권6호
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• pp.15-22
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• 2014

With a conventional positioning apparatus, it is very difficult simultaneously to achieve desired driving ranges and precision levels at the sub-micrometer level. Generally, a lead screw and friction drive have been used as servo control systems. These have large driving ranges, and high-speed positioning is feasible. In this study, we present a global servo system controlled by a laser interferometer acting as a displacement measurement sensor for achieving positioning accuracy at the sub-micrometer level.

• 제어로봇시스템학회논문지
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• 제11권9호
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• pp.802-809
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• 2005

A hybrid genetic algorithm is proposed for the problem of generating laser torch paths to cut a stock plate nested with free-formed parts each having a set of sub-parts. In the problem, the total unproductive travel distance of the torch is minimized. The problem is shown to be formulated as a special case of the standard travelling salesman problem. The hybrid genetic algorithm for solving the problem is hierarchically structured: First, it uses a genetic algorithm to find the cutting path f3r the parts and then, based on the obtained cutting path, sequence of sub-parts and their piercing locations are optimally determined by using a combined genetic and heuristic algorithms. This process is repeated until any progress in the total unproductive travel distance is not achieved. Computational results are provided to illustrate the validity of the proposed algorithm.

• Journal of Welding and Joining
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• 제14권1호
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• pp.15-23
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• 1996

용접은 힘든 작업환경 때문에 심한 인력난을 겪고 있는 3D 업종 중의 하나이 다. 특히 아크용접을 위해서는 숙련된 작업자가 필요하기 때문에 인력난은 더욱 심각 하다. 현장에서 젊은 작업자는 보기 힘들고 대부분의 작업자는 중년이상의 나이이다. 따라서 머지않아 많은 업체들이 인력난으로 조업을 중단해야 할 사태도 우려하지 않을 수 없는 형편이다. 이러한 문제점들을 해결할 수 있는 용접자동화는 최근 많은 관심을 끌고 있으며 이제 세계적인 추세가 되었다. 용접자동화의 이점은 무엇보다도 일정한 수준의 품질과 생산성에서 찾아볼 수 있다. 용접자동화에서는 가공자동화와는 달리 시스템의 자율성이 특히 중요하다. 작업조건의 설정, 용접봉의 위치와 방향 등은 전적 으로 컴퓨터와 센서시스템을 장착한 로봇에 의해 결정되어야 한다. 따라서 작업자들이 용접에 이용하는 각종 지능적인 능력을 습득하고 이를 각종 제어기와 센서로 모방하여 자율적으로 제어하는 인공지능기술을 응용하는 용접을 로봇의 개발에 관한 각종 연구 가 활발히 진행되고 있다.

• 반도체디스플레이기술학회지
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• 제20권3호
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• pp.77-82
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• 2021

This numerical study focuses on the analysis of fume particle dispersion characteristics over the surface of target workpiece in laser micro-hole machining process. The effects of oblique stagnation flow over fume generating machining point are examined by carrying out a series of three-dimensional random particle simulations along with probabilistic particle generation model and particle drag correlation of low Reynolds number. Present computational model of fume particle dispersion is found to be capable of assessing and quantifying the fume particle contamination in precision hole machining which may influenced by different types of air flow patterns and their flow intensity. The particle size dependence on dispersion distance of fume particles from laser machining point is significant and the effects of increasing flow oblique angle are shown quite differently when slot blowing or slot suction flows are applied in micro-hole machining.

• 한국정밀공학회지
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• 제14권11호
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• pp.147-153
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• 1997

Fault diagnosis technique in machining system which is one of engineering techniques absolutely necessary to automation of manufacturing system has been proposed. As a whole, diagnosis process is explained by two steps: sensor data acquisition and reasoning current state of system with the given sensor data. Flexible disk grinding process implemented in milling machine was employed in order to obtain empirical manufacturing process information. Resistance force data during machining were acquired using tool dynamometer known as sensor which is comparably accurate and reliable in operation. Tool status during the process was analyzed using influnece diagram assigning probability from the statistical analysis procedure.

• 한국정밀공학회지
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• 제19권2호
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• pp.106-113
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• 2002

Stencil is used normally as a mask for seeder pasting on pad of PCB. The objective of this study is to develop stencil cutting system and determine optimal conditions which make good-quality stencil by using a Nd:YAG laser. The effects of process parameters such as laser power, type of mask, gas pressure, cutting speed and pulse width old the cut edge quality were investigated. In order to analyse fille cut surface characteristics(roughness, kerf width, dross) optical microscopy, SEM photography and roughness test were used. As a result, the optimal conditions of process parameters were determined, and the practical feasibility of the proposed system is also examined by using a commercial Gerber file for PCB stencil manufacturing.

• 한국음향학회지
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• 제13권6호
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• pp.45-49
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• 1994

본 논문에서는 출력이 2W이고 파장이 $10.6{\mu}m$인 CW $CO_{2}$ 레이저와 PZT 5A 음향변화 소자를 사용하여 광음향 영상처리 시스템을 구성하였으며 샘플로서 5mm 두께의 스텐레스강을 사용하여 그 표면에 폭과 깊이가 $50{\mu}m$, 선간격이 각각 $200{\mu}m$, $300{\mu}m$가 되도록 3선의 선형결함을 방전가공하고 $2.2mm\times2mm$의 스캔범위를 취하여 표면결함을 영상화한 결과 레이저 변조주파수가 100Hz 일때 $50{\mu}m$의 해상력을 갖는 양질의 영상을 보였다.