• 대한임베디드공학회논문지
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• 제7권2호
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• pp.61-70
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• 2012

This paper describes terrain-adaptive attitude controller for a hybrid mobile platform which operates in wheel & track mode. The wheel mode of the hybrid mobile platform allows quick driving performance in the flatland, while the track mode provides adaptive movement in the rough ground or stairway. The switching of the platform between two modes is automatically controlled by attitude controller algorithm. In addition, in the track mode, the platform automatically adjusts its attitude angle to overcome the obstacles in front. This paper demonstrates the attitude controller for the aforementioned wheel-track hybrid mobile platform in order to overcome terrain obstacles by using an adaptive method. The driving performance of the hybrid mobile platform has been tested and verified in various surrounding environments in both wheel and track mode. Further, this paper presents the experiments by using the track structure of mobile platform on forming adaptive attitude under various types of obstacles. The practicability and effectiveness of the proposed attitude controller of the platform has been demonstrated in urban building and a test-bed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.315-316
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• 2010

• 로봇학회논문지
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• 제5권3호
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• pp.270-277
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• 2010

Various robot platforms have been designed and developed to perform given tasks in a hazardous environment for the purpose of surveillance, reconnaissance, search and rescue, and etc. We have considered a terrain adaptive hybrid robot platform which is equipped with rapid navigation on flat floors and good performance on overcoming stairs or obstacles. Since our special consideration is posed to its flexibility for real application, we devised a design of a transformable robot structure which consists of an ordinary wheeled structure to navigate fast on flat floor and a variable tracked structure to climb stairs effectively. Especially, track arms installed in front side, rear side, and mid side are used for navigation mode transition between flatland navigation and stairs climbing. The mode transition is determined and implemented by adaptive driving mode control of mobile robot. The wheel and track hybrid mobile platform apparatus applied off-road driving mechanism for various professional service robots is verified through experiments for navigation performance in real and test-bed environment.

• 자동차안전학회지
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• 제13권1호
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• pp.14-25
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• 2021

This paper presents a RLS based adaptive sliding mode observer (A-SMO) for unknown fault reconstruction in longitudinal autonomous driving. Securing the functional safety of autonomous vehicles from unexpected faults of sensors is essential for avoidance of fatal accidents. Because the magnitude and type of the faults cannot be known exactly, the RLS based A-SMO for unknown acceleration fault reconstruction has been designed with relationship function in this study. It is assumed that longitudinal acceleration of preceding vehicle can be obtained by using the V2V (Vehicle to Vehicle) communication. The kinematic model that represents relative relation between subject and preceding vehicles has been used for fault reconstruction. In order to reconstruct fault signal in acceleration, the magnitude of the injection term has been adjusted by adaptation rule designed based on MIT rule. The proposed A-SMO in this study was developed in Matlab/Simulink environment. Performance evaluation has been conducted using the commercial software (CarMaker) with car-following scenario and evaluation results show that maximum reconstruction error ratios exist within range of ±10%.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.1060-1061
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• 2015

This paper presents the control method of MPPT (Maximum Power Point Tracking) using back-to- back converter. The windturbine system use PMSG(ermanent Magnet Synchronous Generator) system considering low maintenance costs and driving performance at low wind. This paper use the adaptive sliding mode control to the torque control. Proposed method was analyzed mathematically.

• 제어로봇시스템학회논문지
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• 제22권11호
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• pp.919-924
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• 2016

This paper proposes a robust control design method for improving the cornering stability of a personal electric vehicle equipped with in-wheel motors. In general, vehicles undergo severe parameter variations and unpredictable disturbances with respect to a wide range of driving conditions (e.g., road surface conditions and vehicle velocity conditions). For this reason, robust control design techniques are required to guarantee consistent driving performances and robustness against various driving conditions. In this paper, an adaptive sliding mode control method is employed to enhance cornering stability by controlling the direct-drive in-wheel motors independently. Additionally, in order to confirm the effectiveness of a proposed control method, real driving tests with an experimental personal electric vehicle are performed.

• 제어로봇시스템학회논문지
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• 제17권6호
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• pp.558-565
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• 2011

Various robot platforms have been designed and developed to perform given tasks in a hazardous environment for surveillance, reconnaissance, search and rescue, etc. We considered a terrain-adaptive and transformable hybrid robot platform that is equipped with rapid navigation capability on flat floors and good performance in overcoming stairs or obstacles. The navigation mode transition is determined and implemented by adaptive driving mode control of the mobile robot. In order to maximize the usability of wheel-track hybrid robot platform, we propose a terrain-adaptive and user-friendly remote controller and verify the efficiency and performance through its navigation performance experiments in real and test-bed environments.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 D
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• pp.647-649
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• 2000

Brushless DC motors are widely used in many industrial fields as an actuator of robot and driving power motors of electrical vehicle. In this paper adaptive fuzzy sliding mode scheme is developed for velocity control of brushless DC motor. The proposed scheme does not require an accurate dynamic model. yet it guarantees asymptotic trajectory tracking despite torque variations. Numerical simulation and DSP-based experimental works for velocity control of brushless DC motor are carried out.

• 한국컴퓨터정보학회논문지
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• 제23권2호
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• pp.1-7
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• 2018

The adaptive optics for compensating for optical wavefront distortion due to atmospheric turbulence has recently been used in systems that improve beam quality by eliminating the aberrations of high power laser beam wavefront. However, unseen-mode, which can not be measured in the wavefront sensor, increases the instability of the laser beam wavefront compensator on the adaptive optics system. As a method for improving such instability, a mathematical method for limiting the number of singular values is used when generating the command matrix involved in generation of the drive command of the wavefront compensator. In the past, however, we have relied solely on experimental methods to determine the limiting range of the singular values. In this paper, we propose a criterion for determining the limiting range of the singular values using the driving characteristics and the correlation technique of the wavefront compensator's actuators and have proved its performance experimentally.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.402-403
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• 2009

A variety of power reduction technologies is introduced and the benefits of the technologies are discussed. PenTile$^{(R)}$ DBLC (Dynamic Brightness LED Control) combined with SABC (Sensor-Based Adaptive Brightness Control) enables to achieve the average LED power consumption to one third. The panel power reduction of 25% can be achieved with low power driving technology, ALS (Active Level Shifter). MIP (Memory In Pixel) is expected to be useful in transflective display because the whole display area can be utilized in reflective mode with power consumption of 1mW.