• Journal of IKEEE
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• v.24 no.3
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• pp.735-742
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• 2020

The pick & place module is used as a core module in the process equipment for producing and inspecting semiconductor components. The conventional pick & place module has the disadvantage that the precision and durability of the system are reduced and the size and weight of the module are increased by using a conversion device that converts rotary motion into linear motion. In this study, we proposed a pick & place module that implements up-and-down linear motion without a conversion device by improving such disadvantage and employs a linear motor with no limit on average thrust and travel distance. Design parameter values, that can reduce cogging force while maintaining average thrust by selecting parameters for designing a core type linear motor with a large thrust to volume ratio and analyzing the effect of cogging force according to design parameter changes through magnetic analysis, was selected. Average thrust and cogging force were measured for the pick & place module composed of the manufactured linear motor and compared with the design values.

• Structural Engineering and Mechanics
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• v.80 no.5
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• pp.503-522
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• 2021

This paper investigates experimentally and numerically the influence of drilling process on the mechanical and thermomechanical behaviors of woven glass fiber reinforced polymer (GFRP) composite plate. Through the experimental analysis, a CNC machine with cemented carbide drill (point angles 𝜙=118° and 6 mm diameter) was used to drill a woven GFRP laminated squared plate with a length of 36.6 mm and different thicknesses. A produced temperature during drilling "heat affected zone (HAZ)" was measured by two different procedures using thermal IR camera and thermocouples. A thrust force and cutting torque were measured by a Kistler 9272 dynamometer. The delamination factors were evaluated by the image processing technique. Finite element model (FEM) has been developed by using LS-Dyna to simulate the drilling processing and validate the thrust force and torque with those obtained by experimental technique. It is found that, the present finite element model has the capability to predict the force and torque efficiently at various drilling conditions. Numerical parametric analysis is presented to illustrate the influences of the speeding up, coefficient of friction, element type, and mass scaling effects on the calculated thrust force, torque and calculation's cost. It is found that, the cutting time can be adjusted by drilling parameters (feed, speed, and specimen thickness) to control the induced temperature and thus, the force, torque and delamination factor in drilling GFRP composites. The delamination of woven GFRP is accompanied with edge chipping, spalling, and uncut fibers.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.5
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• pp.141-148
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• 2003

In the recently, the necessity of the hybrid type linear stepping motor(HLSM) of linear motion digital actuator has been increased in the various fields of the automatic control system. The HLSM is directly performed without any converting mechanism. Therefore, the HLSM is better advantaged in the efficiency and economical view than a rotary stepping motor. In this paper, we have designed an optimum tooth shape by the 2D finite element method(FEM) to develop the HLSM with longitudinal flux machine(LFM) type, and calculated the thrust force and normal force. And we have manufactured the prototype of it, and have experimented the thrust force characteristics of it.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.11
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• pp.91-98
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• 2004

TFLIM(Transverse Flux Linear Induction Motor), making its closed magnetic path with the direction of the traveling field orthogonal, had been developed to decrease an edge effect of the general induction motor. To control the levitation force and the thrust force on the secondary part of TFLIM independently, the various methodologies have been presented. When we try to achieve the independent control using only the multi-phase inputs assigned in the stator coils as an approach, in which condition we can minimize the coupling effect between two forces\ulcorner In this paper, we show the qualitative influence of a slip frequency, an ac magnitude, a dc offset superposed in the ac power, and a major parameter of TFLIM on the couple through the computer simulation. And to realize the independent motions between levitation and thrust motion without any auxiliary means fur isolation of the secondary part of TFLIM, the decouple compensator is suggested, including the experimental results.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.6
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• pp.653-663
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• 2012

The study considers the high maneuverability flight and path optimization is conducted to investigate the appropriate generation of the lift and thrust considering the angle of the stroke plane. The path optimization problem is defined according to the various purposes of the high maneuverability flight. The flying purposes are to maximize thrust force, lift force and both lift and thrust forces. The flapping motion of the airfoil is made by a combined sinusoidal plunging and pitching motion in each problem. The optimization process is carried out by using well-defined surrogate models. The surrogate model is determined by the results of two-dimensional computational fluid dynamics analysis. The Kriging method is used to make the surrogate model and a genetic algorithm is utilized to optimize the surrogate model. The optimization results show the flapping motions for the high maneuverable flight. The effects on the generation of lift and thrust forces are confirmed by analyzing the vortex.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.10
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• pp.2147-2153
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• 2009

A Hybrid type Linear Pulse Motor(LPM) for low cost is designed as single side stator structure. The static and dynamic characteristics measurement systems are designed. Experimental measurement systems, which measure the static and dynamic characteristic of the LPM, are uggested for the prototype LPM. It becomes known the values of the thrust forces. Finally the microstep drive method is adopted to the drive of prototype LPM. The waveform difference is measured between the microstep method and rectangular wave. From the experimental results, it can be confirmed that the repetitive ripple of the thrust force of the prototype LPM are reduced by taking the microstep drive method.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.572-582
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• 2017

It is definitely important to measure thrust during ground test when developing air-breathing engine, and in case of air-breathing engine, gross thrust should be calculated considering not only the measured thrust but also the force induced by the air flow of engine intake. Also, side thrust like yaw and pitch should be measured and analyzed using multi-component thrust measurement system. Engine performance was accurately evaluated by calculating the gross thrust of air breathing engine precisely which is analyzed from below serial procedure: labyrinth seal isolation, 1-axis gross thrust calculation, develop multi-component thrust measurement system, and side thrust analysis.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.610-613
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• 1995

In addition to propulsive force to a flying vehicle, a rocket propulsion system can provide moments ro rotatate the flying vehicle and thus provide control of the vehicle's attitude and flight path. By controlling the direction of the thrust vectors, it is possible to control a vehicle's pitch, yaw, and roll motions. In this paper, we will introduce general thrust vector control mechanisms.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.253-254
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• 2002

The determination of thrust is very important in hypersonic air-breathing propulsion design and evaluation. Because of the short flow-residence time in the combustor, the evaluation of engine performance is strongly influenced upon the engine thrust. Conventional methods to determine the thrust is using thrust stand or force measurement system. However, these methods cannot be applied to the case where thrust stands are impractical, such as free jet testing of engines, and model combustor. With this reason, the thrust determination method from measured pilot pressure is considered and evaluated.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.2
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• pp.349-357
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• 1990

Power transmission characteristics and speed ratio-torque load-axial force relationship for a metal V-belt CVT were investigated theoretically and experimentally. In the metal V-belt CVT drive, it was found that the power was transmitted by thrust force and that band tension should be greater than compression force between the metal blocks. The experimental results for the speed ratio-torque load-axial force relationship showed good agreement with those predicted using equations developed from theoretical considerations.