• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 춘계학술대회 논문집
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• pp.272-277
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• 2003

In order to predict vibration during end-milling process, the cutting dynamics was modelled by using neural network and combined with structural dynamics by considering dynamic cutting states. Specific cutting constants of the cutting dynamics model were obtained by averaging cutting forces and tool diameter, cutting speed, feed, axial depth radial depth were considered as machining factors. Cutting farces by test and by neural network simulation were compared and the vibration during end-milling was simulated.

• 한국공작기계학회논문집
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• 제12권5호
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• pp.1-7
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• 2003

In order to predict vibrations occurred during end-milling processes, the cutting dynamics was modelled by using neural network and combined with structural dynamics by considering dynamic cutting state. Specific cutting force constants of the cutting dynamics model were obtained by averaging cutting forces. Tool diameter, cutting speed, fled, axial and radial depth of cut were considered as machining factors in neural network model of cutting dynamics. Cutting farces by test and by neural network simulation were compared and the vibration displacement during end-milling was simulated.

• 한국정밀공학회지
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• 제11권2호
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• pp.85-94
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• 1994

The cutting mechanism of ultrasonic vibration machining is characterized as two phases, that is, an impact at the cutting edge and a reduction of cutting force due to non-contact interval between tool and workpiece. In this paper, in order to identify cutting dynamics of a system with ultrasonically vibrated cutting tool, an ARMA modeling is performed on experimental cutting force signals which have a dominant effect on cutting dynamics. The aim of this study is, through Dynamic Date System methodology, to find the inherent characteristics of an ultrasonic vibration cutting process by considering natural frequency and damping coefficient. Surface roughness and stability of cutting process under ultrasonic vibration are also considered

• 한국정밀공학회지
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• 제16권2호통권95호
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• pp.104-115
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• 1999

Cutting process, in general, is a closed-loop system consisting of structural dynamics and cutting dynamics, with the cutting forces and the relative displacements between tool and workpiece being the associated variables. There have been a number of works on modeling the cutting process of endmilling, most of which assumed that either one of the tool or workpiece be negligible in tis displacement. In this paper, the relative displacement between tool and workpiece was considered. The proposed model used experimental modal analysis for structural dynamics and an instantaneous uncut chip thickness model for cutting dynamics. Simulation of the model, a time varying cutting system, was performed using 4th order Runge-Kutta method. Subsequent simulation results were utilized to predict chatter over a variety of experiments in slotting operation, showing good agreement.

• 대한기계학회논문집
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• 제5권4호
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• pp.303-311
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• 1981

Machine tool dynamics is investigated under actual working conditions. Experimental evaluation of cutting dynamics in a lathe is made with cutting conditions and cutting positions varied. The thrust force and the toolpost and tailstock accelerations during turning process are modelled and analyzed by employing Dynamic Data System methodology. It is found that two acceleration signals are good enough to replace the thrust force, when used for machine tool identification under cutting process and for chatter detection.

• 한국정밀공학회지
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• 제10권4호
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• pp.73-80
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• 1993

There and two important variables in machining process control, which are feed and cutting speed. It is possible to improve the machining accuracy and the productivity by maintaining the optimal feed and cutting speed. In this work, a controller is designed to achieve on-line cutting force control based on the modeling of cutting process dynamics established through step response test. Two schemes are proposed and implemented. The first is feed control under the constant spindle speed and the second is spindle speed control under the constant feed. Finally, both are proved to work properly through simulation and experimentation.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 춘계학술대회 논문집
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• pp.536-542
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• 2002

There are two important variables in machining process control, which are feed and cutting speed. In this work, a two degree-of-freedom controller is designed and implemented to achieve on-line cutting force control and position control based on the modelling of cutting process dynamics which are established through step response test. Two schemes are proposed and implemented. The first is feed control under the constant spindle speed and spindle speed control under the constant feed speed. The second is a simultaneous control of feed and spindle speed. The last performs a position control under the constant cutting force. Those are confirmed to work properly. Especially the latter shows a faster response.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.219-224
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• 2002

There are two important variables in machining process control, which are feed and cutting speed. In this work, a two degree-of-freedom controller is designed and implemented to achieve on-line cutting force control based on the modelling of cutting process dynamics which are established through step response test. Two schemes are proposed and implemented. The first is feed control under the constant spindle speed and spindle speed control under the constant fled speed. The second is a simultaneous control of feed and spindle speed. Those are confirmed to work properly. Especially the latter shows a faster response and we'll be evaluated to pare away workpiece by simultaneous control of position and cutting farce sooner or later.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1993년도 춘계학술대회 논문집
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• pp.160-165
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• 1993

The cutting mechanism of ultrasonic vibration machining is characterized as two phases, that is an impact at the cutting edge and a reduction of cutting force due to non-contact interval between tool and workpiece. In this paper, in order to identfy cutting dynamics of a system with ultrasonically vibrated cutting tool, an ARMA modelling is performed on experimental cutting force signals which have a dominant effect on cutting dynamics. The aim of this study is, through Dynamic Data System methodology, to find the inherent characteristics of an ultrasonic vibration cutting process by considering natural frequencyand damping coefficient. Surface roughness and stability of cutting process under ultrasonic vibration are also considered

• 대한기계학회논문집
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• 제15권1호
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• pp.78-89
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• 1991

본 연구에서는 ARSC를 엔드밀링 공정에 적용하여, 절삭력을 추종제어하는 실 예를 제시하고자 한다.제2장에서는 ARSC를 절삭공정에 일반적으로 적용하기 위한 구체적인 이론전개를 설명하여, 제3장에 실시간 시뮬레이션의 방법과 결과를 예시하 고,마지막으로, 제4장에 엔드밀링 절삭시험을 위한 장치의 구성 및 그 결과를 설명하 였다.