• Journal of Institute of Control, Robotics and Systems
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• v.17 no.12
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• pp.1240-1247
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• 2011

The localization of mobile robot in environment is a major concern in mobile robot navigation. So, many kinds of localization techniques have been researched for several years. Among them, the positioning system using ultrasound has received attention. Most of these ultrasonic positioning systems to synchronize the transmitters and receivers are used for RF (Radio Frequencies). However, due to the use of RF, the interference problems can not be avoided and the performance of radio frequencies directly affects the positioning performance. So we proposed the ultrasonic positioning system without synchronizing RF. The proposed system is based on existing USAT (Ultrasonic Satellite System) adopted infrastructure transmitting type, and consists of transmitter and receiver synchronizing modules instead of the radio frequency transmitters and receiver. The ultrasonic transmitters and receivers are synchronized individually by the transmitter and receiver synchronizing modules. In order to calculate the bias between the transmitter and receiver synchronizing modules, new positioning algorithm similar to GPS was proposed. The positioning performance of the improved USAT without synchronizing RF and the validity of the proposed positioning algorithm are verified and evaluated by experiments.

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.1147-1149
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• 1998

This paper presents the result of an analysis on effects of phase compensation on power system stability in the PSS parameter tuning. Synchronizing and damping coefficients are induced from lineal model for generator with PSS. Synchronizing and damping coefficients corresponding to time constants of phase compensation control block are calculated on a single machine, infinite bus test system. The Parameter tuning concepts, basic function, structural elements and performance criteria of PSS are introduced.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.330-333
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• 2003

In this thesis. the application of the synchronizing control of the intelligent indoor lift system is showed. The separate axes of the indoor lift system are driven independently. PID controller, synchronous flexible logic compensating method and tilt sensor are applied to enhance the performance of the intelligent indoor lift system. the tilt sensor senses the horizontal error of the whole system. PID controller and synchronous flexible logic are used to compensate the synchronous errors of both the separate axes and whole system to be zero. Namely, using not the hardware coupling but the software algorithm. the indoor life system is operated without the error. Before applying the real system, the simulation using matlab testifies the possibility of the lift system. And the realization of the system is demonstrated with two DC servo motors. In the experiment test, flexible logic to compensate the synchronous error is chosen by the comparative method. the indoor lift system has to be considered the loading factor as the disturbance. Because the intelligent indoor lift system is developed to support the patients who don't change for themselves to move. finally, the system which considers the weight of the patient as the disturbance can carry the patients safely without synchronous and position error.

• IEMEK Journal of Embedded Systems and Applications
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• v.9 no.5
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• pp.277-283
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• 2014

In this paper, we propose a control system for synchronizing attitude between an Android smartphone and a mobile robot. The control system is comprised of a smartphone and a mobile robot. The smartphone transports its attitude to the mobile robot and receives the attitude of mobile robot through bluetooth communication. Further, the smartphone displays the mobile robot on the screen by using embedded camera, which can be used as a pseudo augmented reality. Comparing the received attitude data from smartphone, the mobile robot measures its attitude by an AHRS(attitude heading reference system) and controls its attitude. Experiments show that the synchronization performance of the proposed system is maintained in the error range of $1^{\circ}$.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.6
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• pp.1112-1121
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• 2011

A microgrid is an aggregation of multiple distributed generators (DGs) such as renewable energy sources, conventional generators, and energy storage systems that provide both electric power and thermal energy. Generally, a microgrid operates in parallel with the main grid. However, there are cases in which a microgrid operates in islanded mode, or in a disconnected state. Islanded microgrid can change its operational mode to grid-connected operation by reconnection to the grid, which is referred to as synchronization. Generally, a single machine simply synchronizes with the grid using a synchronizer. However, the synchronization of microgrid that operate with multiple DGs and loads cannot be controlled by a traditional synchronizer, but needs to control multiple generators and energy storage systems in a coordinated way. This is not a simple job, considering that a microgrid consists of various power electronics-based DGs as well as alternator-based generators that produce power together. This paper introduces the results of research examining an active synchronizing control system that consists of the network-based coordinated control of multiple DGs. Consequently, it provides the microgrid with a deterministic and reliable reconnection to the grid. The proposed method is verified by using the test cases with the experimental setup of a microgrid pilot plant.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.167-169
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• 2011

Construction Automation as a way to solve the problems of lack of skilled labor by decrease in construction population productivity and quality decrease. We are on the way to develop a construction automation system adequate for domestic circumstances in Korea; it is called RCA(Robotic-crane based Construction Automation) system. Climbing hydraulic robot system is a part of RCA system and makes Construction Factory(CF) climb next floor. The controller can control movement needs to be developed for CF safety. Synchronous control the actual field was applied to the controller logic and synchronous control of the process through which the safety has been verified. The purpose of this study that control of climbing hydraulic robot system behavior on real-time, and to improve safety for overall construction automation system through synchronous motion controller.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.41 no.7
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• pp.694-700
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• 1992

The digital computer control systems which are used in time sharing control or remote control may experience intermittent interruptions. Further it can be made unstable by the intermittent interruptions of a control computer. This paper presents a mathematical model with intermittent computer interruptions and an unstable output response through simulation. Also it presents to improve the control quality using extrapolation method in interrupt synchronizing feedback path.

• Journal of the Korean Society of Propulsion Engineers
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• v.23 no.3
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• pp.9-17
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• 2019

Variable guide vanes(VGVs) that consist of link mechanisms and an actuator system are required for an aircraft gas turbine engine to adjust the incidence angle of stator vanes. In this study, we developed a VGV actuator system for three-stage VGVs with two hydraulic actuators. The requirements for the actuator system were derived by analyzing the link mechanisms and air loads, and a hydraulic power-pack was developed based on these requirements. Through a load test using the actuator test-rig and the application of synchronizing control logic with proper control gains, the actuator system could be developed and verified.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.9
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• pp.1064-1072
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• 1999

The basic concepts, which are related to the PSS tuning conditions and performance conditions for the safe of determination of PSS gain and compensation of phasor lagging, are thoroughly investigated in this first part. The performance conditions, where the power system has the lowest inherent damping torque and PSS should provide maximum damping torque, are examined by analysing synchronizing torque and damping torque supplied by the voltage control loop at the oscillation frequency. PSS tuning conditions are also investigated by observing the phasor lagging and the gain, resulted from power system-generator-excitation system depending on operating conditions, such as generator active power, reactive power, transmission impedance and AVR gain. The basic concepts developed in this PartImake it possible to lay foundation for the discussion of PSS tuning in Part II.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.4
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• pp.382-395
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• 1991

A general purpose distributed processes communication control mechanism is a typical approach used for synchronizing concurrent processes involved in communication. The mechanism can provide a framework on which the layered communication architectures and protocols are efficiently implemented. The mechanism is realized under restricted environment where monitor facility is not available by means of simulation using semaphore.