• International Journal of Internet, Broadcasting and Communication
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• 제11권2호
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• pp.11-18
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• 2019

One of the key objectives of control systems is to maintain a system in a specific stable state. To achieve this goal, a variety of control techniques can be used and it is often uses a feedback control method. As known this kind of control methods requires mathematical model of the system. This article presents seesaw unstable system with two propellers which are controlled without use of a mathematical model instead. The goal was to control it using training data. For system control we use a logistic regression technique which is one of machine learning method. We tested our controller on the real model created in our laboratory and the experimental results show that instability of the seesaw system can be fixed at a given angle using the decision boundary estimated from the classification method. The results show that this control method for structural equilibrium can be used with relatively more accuracy of the decision boundary.

• International Journal of Aeronautical and Space Sciences
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• 제8권1호
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• pp.129-139
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• 2007

In this paper, attitude control laws for simultaneous pointing of multiple spacecrafts are considered under a formation flying scenario. The basic approach lies in adaptive feedback gains using relative attitude information or maneuver time approximation for coordinated attitude control. Each control law is targeted to balancing mean motion or to correcting system response to the slowest satellite. The control gain adaptation is constructed by two approaches. The first one is using variable damping gain to manipulate speed of a fast system response, and the second one uses alternate natural frequency of the system under control. The validity and stability of the proposed approaches are examined analytically and tested through numerical simulations.

• 한국통신학회논문지
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• 제32권6A호
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• pp.642-647
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• 2007

HAP(High Altitude Platform)을 이용한 무선 통신 시스템은 기존의 지상 및 위성 시스템보다 여러 고유의 장점을 통해 3세대 IMT-2000 무선 서비스를 제공하기 위한 대체 수단으로 제안되고 있다. W-CDMA HAP 시스템은 지상 이동 통신 시스템과 마찬가지로 인접 셀의 간섭을 줄이면서 시스템 용량을 증가시키기 위한 전력 제어가 가장 중요한 기술 중의 하나이므로 이에 대찬 연구가 요구되는 실정이다. 본 논문에서는 기존의 지상 이동 통신 시스템에서 이용되고 있는 SIR(signal-to-interference ratio) 기반의 DB(distributed balancing) 알고리즘에 HAP 시스템만의 고유의 기하학적 구조에 의한 간섭 프로파일을 도입하여 전력 제어를 행함으로서 기존의 HAP 시스템에 제안되고 있는 DBPA(distance-based power allocation) 알고리즘에 의한 전력 제어보다 성능을 크게 개선시킬 수 있을 뿐만 아니라 안테나 최대 이득(또는 사이드로브 특성 등)에 의해 나타나는 성능 변화를 제거할 수 있다.

• 한국멀티미디어학회:학술대회논문집
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• 한국멀티미디어학회 1998년도 춘계학술발표논문집
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• pp.262-267
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• 1998

A hierarchical motion control system for animation of 3D human character is implemented using the motion database in realtime. The proposed motion control system consists of coordination controller for gait timing and balancing of walking motion, joint servo controller for realistic limb movement, and motion database for goal-directed character animation which makes time-consuming animation relatively easy task. As one example among the various applications of the proposed motion control system. We present a simple virtual reality system in which the motion control system plays a central role in generating realistic motion of virtual human character.

• 조명전기설비학회논문지
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• 제26권9호
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• pp.8-17
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• 2012

This paper proposes high performance control of light emitting diode(LED) drive system for liquid crystal display(LCD) backlight. The CCFL(cold cathode fluorescent lamp)was used to a conventional LCD backlight. Due to improvement on luminous efficiency, long life and wide color gamut, LED has gradually substituted for CCFL as backlight. The backlight using LED is necessary to use many LED. For that reason, the LED backlight is using a lot of LED driving circuits. The many LED driving circuit is generated a current deviation between LED. Eventually, it is caused brightness deviation between LED. Therefore, this paper improves the current deviation using transformer and balancing capacitor to solve this problem. Also, for accurate and uniform brightness control, this paper is applied the artificial intelligent control to a dimming control. This paper is compared with conventional system, and validity of this paper proves through that result.

• 제어로봇시스템학회논문지
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• 제20권7호
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• pp.713-717
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• 2014

In this paper, the travel control of the spherical wheeled robot with a mecanum wheel is impelemented. Four typical wheels or three omni wheels are used to consist of the ball-bot. the slip is occured when the typical wheels is used to the ball-bot. In order to reduce these slip, the spherical wheeled robot with macanum wheels is proposed. Through some experiments, we find that the proposed spherical wheeled robot with a mecanum wheel is superior to the conventional spherical wheeled robot with typical wheels.

• 대한기계학회논문집A
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• 제24권5호
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• pp.1155-1165
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• 2000

Due to the irregularity of walking ground and the inaccuracy in trajectory control of a leg, the mechanical shock and slip on the ground can be caused in the landing and supporting legs of a walkin g robot, and the robot may lose walking stability. Especially in a jointed-leg type walking robot, those problems are much more severe than in the pantograph type since the leg-weight of the jointed-leg type walking robot is relatively heavier than that of the pantograph type in general. In order to secure the walking stability for the jointed-leg type quadrupedal robot under development in KIST(Korea Institute of Science and Technology), a balancing algorithm consisting of the leg compliance control and the body posture control is implemented in this paper, and the effectiveness of the algorithm is verified through experiments.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 추계학술대회 논문집
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• pp.439-443
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• 1996

A fuzzy teaming controller is experimentally designed to control the ball k beam system in this paper. Although most fuzzy controllers have been built just to emulate human decision-making behavior, it is necessary to construct the rule bases by using a learning method with self-improvement when it is difficult or impossible to get them only by expert's experience. The algorithm introduces a reference model to generate a desired output and minimizes a performance index function based on the error and error-rate using the gradient-decent method. In our balancing experiment of the ball ＆ beam system, this paper shows that the fuzzy control rules by learning are superior to the expert's experience.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 B
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• pp.539-541
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• 1997

Fuzzy controller design consists of intuition, and any other information about how to control system, into a set of rules. These rules can then be applied to the system. If the rules adequately control the system, the design work is done well. If the rules are inadequate, the designer must modify the rules. Through this procedure, the system can be controlled. In this paper, we design fuzzy controller composed of two parts, one is balancing controller, the other is angle controller.

• International journal of advanced smart convergence
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• 제7권3호
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• pp.15-22
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• 2018

Nowadays multiple control methods are used in robot control systems. A model, predictor or error estimator is often used as feedback controller to control a robot. While robots have become more and more intensive with algorithms capable to acquiring independent knowledge from raw data. This paper represents experimental results of real time machine learning control that does not require explicit knowledge about the plant. The controller can be applied on a broad range of tasks with different dynamic characteristics. We tested our controller on the balancing problem of a single propeller pendulum. Experimental results show that the use of a supervised machine learning algorithm in a single propeller pendulum allows the stable swing of a given angle.