• Journal of Institute of Control, Robotics and Systems
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• v.15 no.10
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• pp.1047-1055
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• 2009

Since nuclear and chemical materials could damage people and disturb battlefield missions in a wide region, nuclear/chemical reconnaissance systems utilizing multiple mobile robots are highly desirable for rapid and safe reconnaissance. In this paper, we design a nuclear/chemical reconnaissance system including mobile robots. Also we propose time-efficient trajectory planning algorithms using grid coverage and contour finding methods for reconnaissance operation. For grid coverage, we performed in analysis on time consumption for various trajectory patterns generated by straight lines and arcs. We proposed BCF (Bounded Contour Finding) and BCFEP (Bounded Contour Finding with Ellipse Prediction) algorithms for contour finding. With these grid coverage and contour finding algorithms, we suggest trajectory planning algorithms for single, two or four mobile robots. Various simulations reveal that the proposed algorithms improve time-efficiency in nuclear/chemical reconnaissance missions in the given area. Also we conduct basic experiments using a commercial mobile robot and verify the time efficiency of the proposed contour finding algorithms.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.144-147
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• 2001

In ATM Network, many algorithms have been proposed for rate-based ABR flow control. The object of these algorithms is to turn around from cell loss and to use the unused bandwidth by ABR Traffic. These Algorithms are applied to control ABR Traffic by EFCI and ER switches. In this paper, we apply these algorithms to the various stale networks and analysis the characteristics of the algorithms and then attempt to show the loss rate of each algorithms. As the result we compare and analysis the efficiency of them.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.11
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• pp.826-833
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• 1988

In this paper we studied the control of overload which could bring the degradation of performance and threaten the stability of the electronic switching system. In order to get the essential requirement for overload control algorithm, we tried to extract the characteristics of commonly used algorithms by means of simulating overload control alogrithms in numerical stored program control switching model. As the result, we could find that the overload control algorithm which monitored the CPU occupancy had the best call complete rate and good response characteristecs and the algorithm using the offered load as a system state variable had a good grade of service which was represented by a short dial tone delay and 3rd quartile of deal tone delay. however, these control algorithms have no generality and need to get the control parameters by the trial-and-error method. We suggested the guidelines on the design of the overload control algorithm.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.1
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• pp.186-194
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• 1997

The objective of this study is to develope knock control algorithms which can increase engine power without causing frequent knock occurrence. A four cylinder spark-ignition engine is used for the experiments to develop knock control algorithms which use block vibration signals. Knock occurrence is detected accurately by using knock threshold values which consider the difference of transmission path of each cylinder. Spark timing is controlled both simultaneously and individually. With the simultaneous control, torque gain is achieved by retarding the spark timing on knock occurrence in propotion to the knock intensity. The individual knock control algorithm results in higher torque gain than the simultaneous knock control algorithm. The knock occurrence frequency of the individual knock control algorithm is about twice the value of the simultaneous knock control algorithm results. Both control algorithms give similar torque gain of about 3% when they are optimized.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2006.03a
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• pp.645-650
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• 2006

This paper presents the results of a study to verify the sufficient control performance of semiactive tuned mass damper and to identify suitable control methods for semiactive tuned mass damper in structural vibration control. In this study, four control algorithms are considered: on-off displacement based groundhook, on-off velocity based groundhook, clipped optimal and maximum energy dissipation algorithm. For semiactive tuned mass damper, MR damper is considered as a controllable damping device and the command voltage is calculated by the control algorithms. Each of the control theory is applied to the three story shear building excited by three earthquakes. The performance of each algorithm is compared with that of conventional tuned mass damper system using evaluation criteria. The simulation results indicate that semiactive tuned mass damper has control efficiency. Among the control algorithms, on-off displacement based control theory shows the best efficacy and robustness.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.76.2-76
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• 2002

Because of the wheeled mobile robot is modeled by nonlinear system framework and controlled by nonlinear algorithms or fuzzy algorithms, the treatment of wheeled mobile robot is very complecate and conservative. In this paper, a new model of two wheeled mobile robot, which is a type of linear system and treated easily, is presented. And we will show that the control algorithms based on the linear system theory is well work to the wheeled mobile robot by simulation and experiment.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.2
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• pp.163-171
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• 2006

In order to control multi-zone temperatures, a multi-type air-conditioning system may be used. In this study, control algorithms for the compressor and the electronic expansion valve of a multi-type air-conditioning system were developed by using fuzzy logics. The compressor control algorithm was composed of a compressor pressure setpoint algorithm, a compressor pressure setpoint reset algorithm, and a compressor frequency setpoint algorithm. The electronic expansion valve control algorithm was composed of an indoor temperature control algorithm, and a superheat control algorithm. These algorithms were applied to a multi-type air-conditioning system. Test showed good results for the control of a multi-type air-conditioning system.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.10
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• pp.1962-1967
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• 2009

This paper deals with a design of a platform to simulate PRT vehicle operational control algorithms using on-board embedded process board. The configuration of the platform is composed of the central control module, the station control module, man-machine interface and monitoring module. Since PRT system needs inherently very reliable vehicle operational control algorithm in order to avoid the impact between vehicles, it is very important to construct a simulation platform to test a designed vehicle operational control algorithm during the development process For the test of the proposed platform a path of the each moving vehicle is predefined in the central control system before the dispatch order is given to the vehicle. The simulation results show the effectiveness of the proposed simulation platform for test and evaluation of the PRT operational control algorithms.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.9
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• pp.139-145
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• 1997

This study is concerned with the optimizing method of control parameters for a hydraulic speed control system by using genetic algorithms which are general purpose search algorithms based on natural evolution and genetics. It is shown that the genetic altorithms satisfactorily oiptimized control gains of the PI speed control system of an electrohydraulic servomotor and that optimization of control para- meters can be achived without much experience and knowledge for tuning. It is also shown that optimal gains may be determined from fitness distribution curves plotted in given gain spaces.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.12
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• pp.997-1003
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• 2016

This paper presents an application of adaptive algorithms for yaw moment distribution with electronic stability control (ESC) and active rear steering (ARS) in integrated chassis control (ICC). Integrated chassis control consists of upper- and lower-level controllers. In the upper-level controller, the control yaw moment is computed with sliding mode control required to stabilize a vehicle. In the lower-level controller, adaptive algorithms are applied to determine the required brake pressure of ESC and the necessary steering angle of ARS, in order to generate the control yaw moment. Simulation is performed using the vehicle simulation package CarSim to validate the proposed method.