• Journal of the Korean Society for Precision Engineering
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• v.28 no.8
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• pp.878-885
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• 2011

A kinematically-hybrid 5-axis machine tool is analyzed from the perspective of machine tool design. Its kinematic characteristics are pointed out, which should be considered during the conceptual design process. A result of the structural analysis of the machine is presented, which is performed during the detailed design process. It is also presented how we improve the thermal characteristics of the machine tool by changing the installation position of the actuators.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.3
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• pp.130-143
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• 1995

This paper presents a new methodology for on-line tool breadage detection by sensor fusion of an acoustic emission (AE) sensor and a built-in force sensor. A built-in piezoelectric force sensor, instead of a tool dynamometer, was used to measure the cutting force without altering the machine tool dynamics. The sensor was inserted in the tool turret housing of an NC lathe. FEM analysis was carried out to locate the most sensitive position for the sensor. A burst of AE signal was used as a triggering signal to inspect the cutting force. A sighificant drop of cutting force was utilized to detect tool breakage. The algorithm was implemented on a DSP board for in-process tool breakage detection. Experiental works showed an excellent monitoring capability of the proposed tool breakage detection system.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.2
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• pp.208-213
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• 2012

In this paper, the radial error of a rotary table at five-axis machine tool is evaluated by utilizing ISO 230-2 and estimation method using double ball-bar. The geometric error of a rotary table is defined as position dependent geometric errors or position independent geometric errors according to their physical character. Then estimation method of geometric errors using double ball-bar is simply summarized including measurement path, parametric modeling and least squares approach. To estimate representative radial error, offset error, set-up error which affect to the double ball-bar data, mean value of measured data including CCW/CW-direction are used at estimation process. Radial errors are separated from measured data and used for evaluation with ISO 230-2. Finally, suggested evaluation method is applied to a rotary table at five-axis machine tool and its result is analyzed to improve the accuracy of the rotary table.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.6
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• pp.1391-1401
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• 1995

This paper addresses design procedure and testing results of a closed-loop motion control of the cranes. When the object is stopped at the desired position, swinging occurs, and such swinging deteriorates the safety and efficiency of the operation of the crane. Therefore, in this paper, the cascade anti-swing and trolley position feedback controller are designed. Anti-swing controller rapidly eliminates swinging of object and position feedback controller reduces the trolley position error. The performance of this controller is investigated through the computer simulation and experiment. From the results of a series of computer simulations and experiments it can be concluded that proposed controller effectively reduces swinging of the object and trolley position error, which shows this controller can be used as an effective tool for the precise control of overhead cranes.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.51 no.4
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• pp.187-194
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• 2002

Recently, the application of the linear machine far industrial field is remarkable increased, especially for the gantry machine, machine tool system and CNC. In these application fields, high dynamics position control performance Is essentially required in both the steady and the transient state. This pacer presents simple but powerful position control loop based on traditional PID controller. The presented position control algorithm, named 'Unified PID Position Controller'has great features for the linear machine drives such as no over-shoot phenomena and simple gain tuning strategy. Through the experimental results with commercial linear motors, it is shown that the proposed algorithm has excellent dynamics suitable fur linear motions.

• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.139-142
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• 1999

Recently, the application of the linear machine for industrial field is remarkable increased, especially for the gantry machine and machine tool system. In these application, high precise position control performance is essentially required in steady/transient state. This paper presents the generalized PID position control algorithm which have rare sensitivity to mass and disturbance. Through the experimental results, it is shown that the proposed algorithm have good performance for the linear machine drives in the steady state and transient state in spite of the load mass varing.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1996.10a
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• pp.11-14
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• 1996

Samsung Electronics has developed high performance velocity and position controller for induction motors and succeeded in mass production for first time in Lorea. Dynamic performance and final control accuracy of the controller are equivalent to those of AC servo motor controller. At present we adopted the controller as spindle motor drive for Samsung CNC systems and expect its wide use in industry as general purpose velocity and position controller for induction motor.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.291-296
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• 2000

Liner DC motors are widely used for servo-actuator, which would be applied for semiconductor equipments and precise machining systems. we have been developed linear DC motor with high speed, acceleration and position accuracy. From performance test, the position accuracy. From performance test, the position and repeatability accuracy were able to be controlled with 10 ${\mu}{\textrm}{m}$ and $\pm$1 ${\mu}{\textrm}{m}$, respectively. The highest acceleration and speed were obtained 3 G and 2m/sec, respectively. Static thrust force was 270N, and then error was 25%.

• Tribology and Lubricants
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• v.18 no.1
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• pp.49-54
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• 2002

In this study, the characteristics of the hydraulic servo mechanism for proportional position control of a hydraulic construction eguipment were analyzed using the developed analysis tool. The result were used in the others hydraulic system except construcdtion eguipment to improve the static performance of the system, the system parameter effects on the controllable region and the hydraulic servo mechanism variation were studied.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.157-162
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• 2000

The object is design an optimal injection position on the Monitor Cover. In this paper, the defined injection position are three types, which simulate in melting temperature, molding temperature and weld line in variation. We obtained a result from simulation and descried the result related injection pressure with injection position.