• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.179-183
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• 2000

This paper is concerned with achieving the high motion accuracy of linear motion bearing guide according to estimate accuracy average effect of bearing. Accuracy average effect can be obtained b analysis the relationship between motion error of the table and spatial frequency of the rail form error. And influences of ball diameter, ball number, and clock length on block motion error and block number on the table motion error are analyzed theoretically. In addition to, a simple experiment is performed in order to verify theoretical result.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.7
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• pp.64-70
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• 2002

The positioning system fur the ultraprecision machine tool should have nanometer order of positioning resolution. For the purpose of achieving that resolution, various feed drive devices have been proposed and currently hydrostatic lead screw and friction drive are paid attention. It is reported that an angstrom resolution can be achieved by using twist-roller friction drive. So we have manufactured ultraprecision feeding system driven by the twist-roller friction drive and perform performance assessment for problem definition and solution finding. As a result, we found that the twist-roller friction drive is mechanically suitable for ultraprecision positioning but some considerations are needed to get higher resolution.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.977-981
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• 2000

Direct drive linear motors have large potential for use as high speed machine tool feed units since they can increase machining rates and improve servo accuracy by eliminating gear related machining problems. So, in this paper, characteristic of 2-axis linear motor feed unit are studied and control gain are adjusted considering positioning, velocity, acceleration and static stiffness. We confirm linear motor feed unit are affected value of control gain sensitively, because drive directly. From the experiment, this feed unit has l${\mu}{\textrm}{m}$ micro step resolution, 5.7${\mu}{\textrm}{m}$ positioning accuracy and under 60${\mu}{\textrm}{m}$ circularity.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.982-986
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• 2000

Perpendicular guideway mechanism has a different behavior with horizontal guideway mechanism due to the slider weight. So, to decrease its weight effect, counter balances such as weight type and hydraulic cylinder type are used. But it can also make another motion behavior by weight rate of slider and counter balance, its connected position. Therefore, it is necessary to find design parameters and analyze their effect. This paper dealt with the optimal design of perpendicular guideway mechanism. For analysis, the theoretic model as same as real machine tool and sib plate to adjust the clearance was used. Rotational angle and displacement of slider, pressure distribution, friction distribution were calculated. Stick slip, intermittent motion of slider according to friction change was adapted to the perpendicular guideway mechanism.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.5
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• pp.729-737
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• 2009

This paper introduces the machine tools feed system, which can be optimized the control's performance through simulation and the adjustment of the mechanical components. One method simulates the frequency response of the speed-loop with the design value using the MATLAB application, so that all of the interpolation axis can be equal to the response bandwidth, resulting in a high accuracy rate. The other method sees the mechanical component being adjusted by analyzing the results of various experiments. Lastly, this client's program is able to change the parameters that are related to the FFD, as well as the parameters in the friction compensation of the OPEN-CNC.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.11
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• pp.80-85
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• 2001

In Part 2, dynamic cutting force model, thermal behavior model, and feed drive model are presented for development of a virtual machine tool. Some relevant results with brief descriptions for each model are presented to verify the proposed models. Experimental results for each model agreed well with the estimated ones. The developed models in this two-part paper are partially integrated as a comprehensive software environment.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.121-122
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• 2013

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.133-134
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• 2011

• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.90-91
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• 2003

대부분의 가공기 혹은 측정기에 있어 이송테이블은 그 기능수행의 기본을 담당하고 있으며 이송테이블의 운동 정밀도와 고속화는 목표하는 정밀도와 생산성으로 직결된다. 종래에는 형상특성, 열변형 등의 계통 오차만을 오프라인(Off-line)으로 측정하고 소프트웨어적으로 보상하는 방법을 사용하였으나 초정밀 분야에서 요구되는 테이블의 운동정밀도는 기계적 강성한계를 넘는 정밀도이므로, 테이블 이송 시 발생하는 운동오차를 실시간으로 측정하고, 보상할 수 있는 온라인(On-line)개념의 능동형 보상이 필요하다. (중략)

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.3
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• pp.17-24
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• 2003

One of the most important performance criteria related to the gain tuning of controller for CNC machining center is the contour error. This study analyzed circular error by the axis-matched and mismatched cases. To reduce ellipse and radius error, it is necessary to set the gain for each axis to be same bandwidth and high response. Based on the analysis in the frequency domain, we simulate feed system by mathematical model and then predict bandwidth of each axis. For analysis of structure vibration while the each axis is moving, we try the various of measuring method and position loop is improved by jerk limit.