• Journal of the Korean Society for Precision Engineering
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• v.10 no.2
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• pp.54-65
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• 1993

The paper describes and alternative method based on a new idea to measure the circular movement of machining centers. ISO has employed three testing methods for the acceptance tests of machine tools; the first is a rotating one-dimensional probe method, the second is a two-dimensional probe and a master circular ring, and the third is a kinematic ball bar. The last two methods were proposed and introduced by W. Knapp and J. B. Bryan, respectively. The newly developed method is superior to above two methods; the rotating angle can be detected and the rotating radius is variable. Circular movement errors of machining centers were investigated by the analysis of data measured by R- .THETA. method. Followint observations are obtained 1) The errors which depend on positions, i.e., periodical errors by the pitch of ball screws, errors by compensation of backlash and errors by perpendicularity of X and Y-axis, were analyzed. 2) The errors which depend on NC control system, i.e., errors by the unbalance of position-loop-gaians, errors by velocity-loop-gains and errors by feed speeds, were quantiatively analyzed. 3) The method of extracting error information, which uses moving technique of averaging angle and fourier's analysis data mesured by the R- .THETA. method, was proposed.

• IE interfaces
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• v.16 no.1
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• pp.8-15
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• 2003

With rapid growth of internet technology, companies have developed an information system such as the electronic catalog for product data in the E-Business. Due to the heuristic nature of the catalog search for proper tools in the specific process, the intelligent and user friendly methods residing in the search process give a comfortable environment even for the beginners in the field. In this paper, we develop a web based catalog for machining tools especially in Milling process. It has two distinct procedures for the users of the catalog; Search and Analysis. The Search is to select a proper cutter, insert, component combination in the developed relational database based on the cutting process and material. The Analysis is to suggest a recommended optimal cutting conditions based on the machining tools and selected materials. All of these procedures are stored in a server with a program based on the ASP and Java Script where the procedure is initiated by the client using the internet which is accessed through insert. With the success on implementing the above engineering database in the internet, we can provide the foundation for developing PDM with heuristic procedure.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.11
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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.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.6
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• pp.77-85
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• 2002

An analysis method which calculates corrective machining information for improving the motion accuracy of linear motion guide Is proposed in this paper. The method is composed of two algorithms. One is the algorithm fur prediction of the motion errors from rail form error. The other is the algorithm for prediction of rail form error from the motion errors of table. Transfer function is utilized in each algorithm, which represents the ratio of bearing reaction force variation to unit magnitude of spatial frequencies of raid from error. As the corrective machining information is acquired from the measured motion errors of table, the method has a merit not to measure rail form error directly. Validity of the method is verified both theoretically and experimentally. By applying the method, linear motion error of test equipment is reduced from 5.97$\mu$m to 0.58$\mu$m, and reduced from 32.78arcsec to 6.21 arcsec in case of angular motion error. From the results, it is confirmed that the method is very effective to improve the motion accuracy of linear motion guide.

• Journal of Korea Multimedia Society
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• v.21 no.8
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• pp.837-848
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• 2018

Monitoring technology of machining has a long history since unmanned machining was introduced. Despite the long history, many researchers have presented new approaches continuously in this area. Sound based machine fault diagnosis is the process consisting of detecting automatically the damages that affect the machines by analyzing the sounds they produce during their operating time. The collected sound is corrupted by the surrounding work environment. Therefore, the most important part of the diagnosis is to find hidden elements inside the data that can represent the error pattern. This paper presents a feature extraction methodology that combines various digital signal processing and pattern recognition methods for the analysis of the sounds produced by tools. The magnitude spectrum of the sound is extracted using the Fourier analysis and the band-pass filter is applied to further characterize the data. Statistical functions are also used as input to the nonlinear classifier for the final response. The results prove that the proposed feature extraction method accurately captures the hidden patterns of the sound generated by the tool, unlike the conventional features. Therefore, it is shown that the proposed method can be applied to a sound based automatic diagnosis system.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.05a
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• pp.193-199
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• 2002

Analyzing working conditions with shape characteristics of wear debris in a lubricated machine, it can be effect on diagnosis of hydraulic machining system. And it can be recognized that results are processed threshold images of wear debris. But, in order to predict and estimate a working condition of lubricated machine, it is need to analysis a shape characteristic of wear debris and to identify. Therefor, If shape characteristics of wear debris are identified by computer image analysis and the neural network, it is possible to find the cause and effect of wear condition. In this stud)r, wear debris in the lubricant oil are extracted by membrane filter $(0.45{\mu}m)$, and the quantitative value of shape characteristic of wear debris are calculated by the digital image processing. This morphological information are studied and identified by tile artificial neural network. The purpose of this study is to apply morphological characteristic of wear debris to prediction and estimation of working condition in hydraulic machining systems.

• 연구논문집
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• s.27
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• pp.119-126
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• 1997

In this paper, an information management system is developed to systematically maintain facilities which include AS/RS(Automatic Storage & Retrieval System). Stacker Crane, Tool Transport system and Machining Center in FMS pilot plant. It supports various activities such as periodical inspection, maintenance, management of daily operation time, analysis of existing condition and management of information related to facilities.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.1
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• pp.110-116
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• 2013

Curvic coupling of mill turret should maintain disk weight and the cutting resistance which occurs the machining operation and must also have power transmission function. In order to improve machining operation range, the ejecting distance from curvic coupling to the disk must increase as much as possible. But moment is increased by the lack of capacity of the curvic coupling. Increase of moment is the cause of vibration/noise and degradation of machining performance not only stability problem. The manufacturer of mill turret has no the design information between the ejecting distance and the cutting resistance with safety of curvic coupling. Therefore this study describes a finite element analysis model of mill turret using ANSYS workbench. The structural analyses and modal analyses with varying of the ejecting distances and cutting resistances are performed. Finally the equation for relationship between the critical ejecting distance and the cutting resistance is defined under 5 of the safety factor for the maximum von-Mises stress at the curvic coupling.

• Proceedings of the Korea Contents Association Conference
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• 2018.05a
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• pp.437-438
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• 2018

레이저 미세가공 시스템 관련 특허가 일본과 미국에서 1990년대 초반부터 출원이 증가하였으며, 2014년에 가장 많은 특허가 출원되었다. 이스라엘과 미국 국적의 출원인이 1, 2위를 차지하였으며, 전체 375건의 특허 중 상위 10위 출원인의 특허출원 비율이 약 26%로 분석되었다. 비즈니스 모델 분석에서는 비즈니스 모델의 강점을 강화하고 약점을 보완하는 비즈니스 모델 수행 전략을 도출하였다.

• Journal of the Korea Society of Computer and Information
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• v.26 no.10
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• pp.45-51
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• 2021

In this paper, we propose a 3D design method of the vacuum forming method of the front part to improve the lightness and production efficiency of agricultural electric vehicles. For agricultural electric vehicles, lightness and production efficiency are more important than the strength of materials for collision protection. In this paper, we propose a vacuum forming design method that can replace complex machining processes such as laser machining, bending, and painting. The main purpose of this research is to improve product stability, productivity and convenience through 3D design of the front part and development of vacuum forming mold technology. Research procedure follows the 3D modeling of the front part using CATIA, finite element analysis for the structural stability using ABAQUS, manufacturing prototype for the investigation of the dimensions using 3D scanner and actual driving test under agricultural electric vehicle usage environment. The results verifies the proposed 3D design method of the vacuum forming method and are expected to be widely used by agricultural workers through the simplification of the production process of agricultural electric vehicles.