• 한국세라믹학회지
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• 제23권1호
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• pp.13-20
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• 1986

Zirconia soild electrolytes containing 4~10mol% of yttria were prepared by wet-blending of oxides and rea-ction-sintering, Sinterbility and degree of stabilization were optimized for the development of oxygen sensor. Fracture strength thermal expansion coefficient electrical conductivity and galvanic potential were measured and discussed with respect to the amount of ytria addition phase transformation microstructure and degree of stabilization. It was found that sintering and stabilization occurred when the composition was designed to be near the boundary region of $ZrO_2-Y_2O_3$ binary system. In such away a good zirconia solid electrolyte suitable for oxygen sensor could be developed.

• Journal of Astronomy and Space Sciences
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• 제13권2호
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• pp.67-81
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• 1996

The attitude dynamics of KITSAT-1 are modeled including the gravity gradient stabilization method. We define the operation scenario during the initial attitude stabilization period by means of a magnetorquering control algorithm. The required constraints for the gravity gradient boom deployment are also examined. Attitude dynamics model and control laws are verified by analyzing in-orbit attitude sensor telemetry data.

• 전자공학회논문지SC
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• 제49권4호
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• pp.55-60
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• 2012

해상환경에서 감시장비의 운용시 원치 않는 외란 운동으로 장비의 안정화 성능이 저하된다. 본 논문에서는 선상 2축 감시장비의 정밀한 목표물 지향를 위해 자세정보의 좌표변환을 통해 움직임을 보상해주는 기구적 안정화를 적용하였다. 적용 결과, MEMS 센서의 떨어지는 정밀도와 기구적인 제약에 의해 오차를 더 줄일 없어 보완적인 기능으로 영상 안정화를 도입하였다. 또한 본 이중 안정화 방식의 실시간 실행을 위해 6축 운동 시뮬레이터를 포함한 테스트 베드를 구축하였으며, 하드웨어 포함 시뮬레이션 수행을 통해 본 방식의 유용성을 검증하였다.

• 항공우주시스템공학회지
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• 제4권4호
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• pp.18-27
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• 2010

Quadrotor is an aircraft which is possible in Vertical Take-off and Landing(VTOL). This aircraft can not only be created as an Unmanned Aerial Vehicle(UAV), but also can be easily used in various fields because of its simplicity of construction. This study is mainly conducted with two main purposes. The first goal is designing the quadrotor focusing on the lightweight and protecting the airframe. The second purpose is stabilizing the quadrotor's attitude by using the PID controller. MATLAB simulation is performed for obtaining PID gain based on equations of motion. We used the compensation filter technique for the calibration of sensor data. PID gain has been drawn out based on the MATLAB simulation. The efficiency of the attitude control is improved by calibration of sensor data.

• 한국산업융합학회 논문집
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• 제19권1호
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• pp.39-41
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• 2016

In the paper, we propose an stable walking algorithm of biped robot on the ground and working motion stabilization algorithm against external disturbances. We propose obstacle hurdling, incline walking, and going-up stairs algorithm by using infrared sensors and F/T sensors. Also, posture stabilization algorithm against external forces is designed using F/T sensors. Infrared sensors are used to detect the obstacles in he working environment and F/T sensors are used to obtain the ZMP of biped robot. The experimental results show that the biped robot performs obstacle avoidance, obstacle hurdling, walking on the inclined plane by using the proposed walking moton stabilization algorithm.

• 제어로봇시스템학회논문지
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• 제9권3호
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• pp.204-209
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• 2003

The line-of-sight stabilization system is an equipment which is loaded on a vehicle and stabilizes the direction of the line-of-sight of the vision sensor to obtain a not-swayed image in the existence of external disturbances. To obtain accurate Euler angles and angular velocities simultaneously we usually need a control system which uses high-price inertial sensors including Vertical Gyro(VG) or Rate Integrating Gyro(RIG). In this paper, we design and implement a control system of a gimbal, which is a line-of-sight stabilization system using a low-cost mixed algorithm of a rate gyro and an accelerometer instead of a VG and a RIG. In the experiment where we laid the implemented line-of-sight stabilization system on the rate table. we can see the stabilized performance to external disturbances.

• 제어로봇시스템학회논문지
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• 제16권5호
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• pp.411-414
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• 2010

As high quality image is required for digital cameras in recent use, the image stabilization technique has drawn much attention to prevent image degradation from shaky disturbance by users. In this paper, the optical image stabilization (OIS) system for DSLR (Digital Single Lens Reflex) camera is considered. First, the analytic model of an OIS system is presented to demonstrate the mechanism of image destabilization due to unknown disturbance that causes blurry images on CCD sensor. Then, to enhance the stabilization performance, a sliding mode control based on the min-max nonlinear control is introduced. Through the experiments and simulations, the effectiveness of the proposed method will be verified.

• 센서학회지
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• 제24권6호
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• pp.412-418
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• 2015

In this paper, a new method for obtaining PID coefficients which are essential to a temperature stabilization process has been proposed. This method starts from measuring the open loop transfer function of the module, then the closed loop transfer function embodying PID control can be produced based on this. Finally, the simulations using a few PID coefficients and the performance analysis for those results provide the best PID coefficients which are effective in a fast setting to a target temperature, a less current needed, and less deviation from steady state. The measurement using the derived PID coefficients, $K_p=1.6$,$K_i=0.8$,$K_d=0.3$ showed $T_s=7.4[sec]$, %OS = 16, and stabilization within ${\pm}0.02[^{\circ}C]$ for several hours. In addition to light sources like SOA, the proposed method can be utilized for any device needs temperature stabilization.

• 전자공학회논문지D
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• 제34D권4호
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• pp.94-99
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• 1997

A new method of stbilizing the sagnac interferometric fiber optic current sensor inteh presence of birefringences and phase is presented. This method is realized by dividing the output of the ac current signal with the modulation signal output. Using the technique the stability of the current sensor was improve dmore than 4.5 times at 800Arms for 2 hours. The current sensor also shows good linearity up to 100Arms.

• 로봇학회논문지
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• 제18권3호
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• pp.241-250
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• 2023

This paper describes the posture stabilization control of a bipedal transformer robot being developed for military use. An inverted pendulum model with a rectangular that considers the robot's inertia is proposed, and a posture stabilization moment that can maintain the body tilt angle is derived by applying disturbance observer and state feedback control. In addition, vertical force and posture stabilization moments that can maintain the body height and balance are derived through QP optimization to obtain the necessary torques and vertical force for each foot. The roll and pitch angles of the IMU sensor attached to the robot's feet are reflected in the ankle joint to enable flexible adaptation to changes in ground inclination. Finally, the effectiveness of the proposed algorithm in posture stabilization is verified by comparing and analyzing the difference in body tilt angle due to disturbances and ground inclination changes with and without algorithm application, using Gazebo dynamic simulation and a down-scale test platform.