• 로봇학회논문지
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• 제14권1호
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• pp.58-64
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• 2019

The paper proposes a stiffness measurement device composed of a measurement part including six indenters and a fixing part including four fixtures. The device is able to make simultaneously measurements of the stiffness of human arm. The six indenters make use of both position and force control schemes sequentially whenever needed. In addition, the loadcells and the digital encoders are attached to the indenters and electric motors, respectively, so that the data can be provided in real time. On the end of the indenter, two-axis potentiometer is attached in order to measure the angle difference between the applied force axis and the axis normal to the skin of human arm, and to convert the force measured on the loadcell into the actual applied force to skin. For this purpose, the mapping between the voltage output and the angle of potentiometer was obtained by fitting it for each axis. Ultimately, the measurement device was able to measure the stiffnesses of six regions of human arm.

• International Journal of Control, Automation, and Systems
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• 제3권4호
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• pp.533-541
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• 2005

In this paper, a wind turbine with power splitting transmission, which is realized through a novel three-shaft planetary, is presented. The input shaft of the transmission is driven by the rotor of the wind turbine, the output shaft is connected to the grid via the main generator (asynchronous generator), and the third shaft is driven by a control motor with variable speed. The dynamic models of the sub systems of this wind turbine, e.g. the rotor aerodynamics, the drive train dynamics and the power generation unit dynamics, were given and linearized at an operating point. These sub models were integrated in a multidisciplinary dynamic model, which is suitable for control syntheses to optimize the utilization of wind energy and to reduce the excessive dynamic loads. The important dynamic behaviours were investigated and a wind turbine with a soft main shaft was recommend.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 Proceedings of the Korea Automatic Control Conference, 11th (KACC); Pohang, Korea; 24-26 Oct. 1996
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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.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1225-1228
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• 2004

Principles and mechanism of energy transduction of dielectric polymer materials are well known from the various smart material related publications. However their introduction to industrial actuator applications is limited mainly due to difficulties guarantee controllability and reliability. Most of the previous publications have elaborates energy transduction physics of chunk of polymer while development of construction methods for feasible actuators made of the material is rarely proposed. In the present article, a conceptual design of multi-DOF linear polymer actuator construction that is to be controllable with moderate level of control work os introduced. In addition, numerical models that are developed with a unified energy based approach are presented not only for basic working mechanism analysis of the polymetric soft actuator but for providing analytical foundation to expend the concept toward design of multi-DOF actuator controls.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.203-208
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• 2003

In this paper, gait generation algorithm based on Linear Inverted Pendulum Mode is extended considering that the terrain is uncertain and flexible. Deformation of the soft terrain by the weight of the biped robot is taken into account to design the desired motion of the swing leg. Landing time disagreement caused by dynamics of the robot is also considered and a method to adjust gait is proposed. Results of numerical simulation show the effectiveness of the proposed method.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.282-285
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• 2003

Two criteria of good vehicle suspension performance are typically their ability to provide good road handling and increased passenger comfort. So far, The existing active vehicle suspension uses pneumatic and hydraulic actuators that enhance road handling and passenger comfort. But these kinds of actuators have nonlinear characteristic less than an electromagnetic motor. In this research, we are trying to examine the feasibility and the experiment of an active vehicle suspension using electromagnetic motor in order to enhance the ride quality because existing active vehicle suspension using active power sources such as compressors, hydraulic pumps has nonlinear characteristic. Active vehicle suspension using electromagnetic motor will have the ability to behave differently on smooth and rough roads. The desired response should be soft in order to enhance ride comfort, but when the road surface is too rough the suspension should stiffen up to avoid hitting its limits.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1598-1602
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• 2003

The parallel-type mechanism provides more accurate and stiff motion than the serial-type mechanism. However, in case of using the haptic device, the performance of the force reflection can be deteriorated due to the singular points existing in workspace. In this paper, we propose a redundantly actuated parallel 3-DOF haptic device, which is singularity-free in the workspace and has an improved force reflection capability. In addition, we propose a new force distribution algorithm, which can reflect force of both high and low resolution, using two sets of actuator with different size. Redundant actuators are attached to the base frame in order to minimize the inertia of the system. Moreover, a wire and gear reduction system is employed to achieve high force reflection along with soft feeling. We confirm the performance of the force reflection capability throughout simulation.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2713-2718
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• 2003

Some of manufacturing tasks such as sawing task often requires continuous impulsive motion. In case of sawing task, such impulsive motions can be observed between the teeth of the saw and the object. The amount of the external impulse exerted on the object has been treated as an important control parameter. The purpose of this work is to introduce a new concept of an effective mass in sawing task and to suggest an external impulse model in sawing task. A normalized impulse ellipsoid reflecting the velocity direction is employed to visualize the impact geometry. Experiments are performed for soft and hard workpieces to justify the external impulse model in the sawing task. It is demonstrated through simulation and experiment that the proposed external impulse model is effective to characterize the impact property.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2072-2077
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• 2003

Animal-like robots are serving an important role as a linkage between biology and engineering. So, in this paper, we aim to develop a biomimetic microrobot that mimics the locomotion mechanism of a gastropod. This microrobot has 3 DOF (x, y translation and rotation), and has small size, unlimited traveling range, high resolution and low cost. Its movement can be made using propagation wave that is generated by the controllable sinusoidal voltage source and piezoelectric effects. This soft motion that can be generated by propagation wave and piezoelectric mechanism would be useful for the motion on the slippery surface. So we modeled the propagation wave mechanism including piezoelectric effect and friction on the contact surface, and could know the velocity of the microrobot is dependent on the driving frequency, input voltage peak, propagation wavelength and surface friction coefficient. With these results we design the microrobot, and accomplish its fabrication and experimentation. The development of this microrobot shall be aimed to design an autonomous moving actuator like animal. Also it can be used from micromanipulation system technology to biology and medicine.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2003년도 ISIS 2003
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• pp.130-133
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• 2003

The robot has recently emerged as a factor in the daily lives of humans, taking the form of a mechanical pet or similar source of entertainment. A robot system that is designed to co-exist with humans, i.e., a coexistence-type robot system, is important to be "it exists in various environments with the person, and robot system by which the interaction of a physical, informational emotion with the person etc. was valued". When studying the impact of intimacy in the human/robot relationship, we have to examine the problems that can arise as a result of physical intimacy(coordination on safety in the hardware side and a soft side). Furthermore, We should also consider the informational aspects of intimacy (recognition technology, and information transport and sharing). This paper reports the interim results of the research of a system configuration that enhances the physical intimacy relationship in the symbiosis of the human and the robot.