• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.24.2-27
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• 1996

This paper is a study on the fuzzy force control of a miniature gripper driven by piezoelectric bimorph actuator. The system is composed of two flexible cantilevers, a stepping motor, a laser displacement transducer and two semiconductor force sensors attached to the beams. Obtained results show that the present artificial finger system works well as a miniature gripper, which produces approximately 0.06N force in the maximum. Further, the fuzzy position/force control algorithm is applied to the soft-handing gripper for stable grasping of a object. It revealed that the fuzzy rule-based controller be efficient controller for the stable drive of the flexible miniature gripper. It also showed that two semiconductor strain gauges located in the flexible beam play an important roles for force control, position control and vibration suppression control.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.5 no.1
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• pp.45-50
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• 2006

This paper shows a new precision actuator of MUTM(miniature universal testing machine) for the testing of compression and tensile load on the MEMS materials and structures. The MUTM consists of a sample holder, an ultraprecision precision actuator(tranlation stage) and load sensor. The precision actuator has been developed for generating displacements with nanometer accuracy and a dynamic range of 1mm simultaneously. In this paper, it can be made by using the displacement property of bi-morph type PZT, which is able to extend the long range(stroke) according to cantilever size. However, it is not enough to be generated for compression and tensile load in miniature universal testing machine. Therefore, three dozen bi-morph type PZTs are used for generating the load. The load and displacement of the precision actuator are 35g and 0.4mm respectively.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.12
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• pp.16-19
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• 2000

• The Journal of Korea Robotics Society
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• v.16 no.2
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• pp.79-85
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• 2021

Soft fluidic actuators (SFAs) are widely utilized in various areas such as wearable systems due to the inherent compliance which allows safe and flexible interaction. However, SFA-driven systems generally require a large pump, multiple valves and tubes, which hinders to develop a miniaturized system with small range of motion. Thus, a highly integrated soft actuator needs to be developed for implementing a compact SFA-driven system. In this study, we propose an electro-hydraulic soft zipping actuator that can be used as a miniature pump. This actuator exerts tactile force as a dielectric liquid contained inside the actuator pressurized its deformable part. In addition, the proposed actuator can estimate the internal dielectric liquid thickness by using its self-sensing function. Besides, the electrical characteristics and driving performance of the proposed system were verified through experiments.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.3
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• pp.272-281
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• 2015

Miniature smart-bullet is a human-carrying guided missile designed to hit a target easily while having a miniature size. Contrary to the normal missiles, miniature smart-bullet is highly expected to enhance the military strength and survival rate of troops by its compact size readily carriable to a single soldier. In this paper, previously developed techniques, activities and patents of miniature smart-bullet, particularly its structural shape and actuators are surveyed. Furthermore, analysis of required techniques to develop a miniature smart-bullet are also discussed for upcoming conceptual design.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.2
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• pp.44-49
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• 1999

This paper is concerned with the theoretical and experimental study on the force conrtrol of a miniature robotic gripper. The gripper is an uniform flexible cantilever equipped with a distributed set of compact force sensor. As an actuator piezoelectric acturator, piezoelectric acturator is fixed with cupper plate at which the beam is clamped. The mathematical model of the assembled electro-mechaincal system is developed. The force sensor is described by a set of concentrated mass-spring system. The formulated equations of motion are applied to he study of a control problem where the gripper is commanded to grip an object The usefulness of the PID control technique is verified by experiment.

• Tribology and Lubricants
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• v.26 no.1
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• pp.44-51
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• 2010

A miniature shear testing machine was designed and developed, adopting a piezoelectric actuator with mechanical advantage using 4 levers in order to investigate shear behavior of a small solder ball. The final output displacement was initially expected to be 2.88 mm without load resistance, considering the lever ratio of 24 and the piezo displacement of 0.12 mm with an exciting voltage of 10 V. However, the final plunger displacement ${\Delta}{\upsilon}$ can be expected as ${\Delta}{\upsilon}=2.88-3.04{\times}10^{-4}F$ as a function of piezoelectric force F due to the stiffness of various levers and connectors and piezo actuator. The shear behavior of lead-free solder ball in diameter of $760{\mu}m$ was successfully investigated in a speed range of 2 mm/s~0.0035 mm/s using this designed device.

• The Journal of Korea Robotics Society
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• v.8 no.3
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• pp.143-149
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• 2013

This paper presents a new miniature haptic display to convey ample haptic information to a user of a handheld interface. There are buttons on interfaces or general electronic devices, but existing buttons provide haptic feedback of only one passive pattern to a user. Because humans perceive tactile and kinesthetic information simultaneously when they handle objects the proposed actuator provides both sensations at once. It is able to generate various levels of kinesthetic sensations when pressing a button under diverse situations. Also, vibrotactile feedback can be delivered for exciting haptic effects with numerous patterns. Its performance was evaluated in accordance with the resistive force by changing the intensity of the input current. Experiments show that the proposed actuator has the ability to provide numerous haptic sensations for more realistic and complex haptic experiences.

• 정보저장시스템학회:학술대회논문집
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• 2005.10a
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• pp.195-196
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• 2005

We report the new design of a miniature electromagnetic actuator for probe-based data storage with anti-vibration mechanism. The actuator consists of a media substrate, silicon frame, 2 pairs of magnets, a spacer, and a printed circuit board (PCB). The total area of the device is $11.2{\times}11.2 mm^2$ while the data recording area is $7.4{\times}7.4 mm^2$. A net momentum fee structure was included for high vibration resistance. The simulation shows that the lateral vibration can be reduced to below 100 nm for 1 G acceleration if the counter mass is adjusted with $1\%$ difference. The peak power for ${\pm}50 {\mu}m$ displacement is below 50 mW for a actuator with a resonance at 200 Hz.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.1
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• pp.148-157
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• 2017

Miniature guided-bullet is an advanced military technology of developing guided missile which is designed to hit a target precisely while having easily carriable miniature size. A key issue of developing such system involves size reduction of the original guided missile system, and this in turn arouses stiffness issue regarding small and thin sized control surface. In this study, procedures on how to calculate the critical flutter speed of special type of control surface with the change of its dimension or material property is arranged. During this procedure, design parameters related to critical flutter speed are abridged to help preliminary design of similar structure even faster than time-consuming, and cumbersome computer analysis.