• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.550-552
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• 2008

A small hall thruster with a thrust of about 10 mN and a specific impulse of about 1500 s is being developed with an intent to control or maintain the orbits of small satellites. The total mass, consumed electric power and efficiency of the thruster are approximately 10 kg, 300W and 30%, respectively. The thruster system consists of a hall thruster with a cylindrical cross section, a power processing unit and a Xenon(Xe) gas feed system. Laboratory examination of the thruster performance finds that the thruster meets the design specification.

• Transactions on Control, Automation and Systems Engineering
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• v.3 no.4
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• pp.257-261
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• 2001

Nonlinear pulse width modulation (PWM) controlled system is considered to achieve control performance of thruster controlled spacecraft. The actual PWM controlled motions occur, very closely, around the average model trajectory. Furthermore nonlinear PWM controller design can be directly applied to thruster controlled spacecraft to determine thruster on-time. Sliding mode control for attitude tracking of three-axis thruster-controlled spacecraft is presented. Simulation results are shown which use modified Rodrigues parameters and sliding mode control law to achieve attitude tracking of a three-axis spacecraft with thrusters.

• 한국연소학회:학술대회논문집
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• 2012.11a
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• pp.295-296
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• 2012

In Korea, study of monopropellant thruster have been started from 1990s by KARI (Korea Aerospace Research Institute). 5N hydrazine thruster that is a first Koreanized hydrazine thruster, have been used as flight model for several satellite. In parallel, in order to retain core technology for monopropellant thruster, catalyst and test facility development have been carried out and successfully completed. On the basis of these technology, KARI is performing development of 1N/200N hydrazine thruster and basic research of green propellant thruster.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.5
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• pp.490-495
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• 2009

A small Hall-effect thruster with a thrust range near 10 mN and a specific impulse of about 1500 s has been designed to control or maintain the orbits of small satellites. The thruster system consists of a hall-effect thruster head, a power processing unit and a Xenon (Xe) gas feed system. The total mass, the consumed electric power and the efficiency of the thruster are approximately 10 kg, 300W and 30%, respectively. Analyses results that support the selection of the thruster for small satellites are provided along with a brief description of the thruster system.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.468-472
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• 2003

MRE-1 dual thruster module(DTM) which will be installed to the present under development KOMPSAT(Korea Multi-Purpose Satellite) can provide reliable and cost-effective means of propulsive control for attitude and maneuvering control system. Thruster heat shield, one of the main components of DTM, is designed to intercept the radiative heat exchange between thruster and satellite during firing. The inside diameter of the current configuration will be decreased a little compared with that of the previous one due to manufacturing method change. Therefore, the possibility of interference between thruster and heat shield due to configuration change is investigated through structural analysis and their results are described in this paper.

• Journal of computational fluids engineering
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• v.21 no.1
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• pp.72-77
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• 2016

In this study, effects of thurster axis tilting angle on the thruster-hull interaction and propulsion performance in a dynamic positioning system of offshore plant are numerically investigated. Straight and 7-degree tilted downward thruster models as a form of ducted propeller are considered. For numerical simulations, Reynolds averaged Navier-Stokes equations with SST turbulence model are solved by using STAR-CCM+. Results show that thruster-hull interaction is reduced in 7-degree tilted thruster model with lower vortex strength between thruster and hull bottom, although the propulsion performance does not have noticeable difference in a bollard condition.

• Ocean Systems Engineering
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• v.1 no.4
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• pp.297-315
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• 2011

New applications of streamlined Autonomous Underwater Vehicles require an AUV capable of completing missions with both high-speed straight-line runs and slow maneuvers or station keeping tasks. At low, or zero, forward speeds, the AUV's control surfaces become ineffective. To improve an AUV's low speed maneuverability, while maintaining a low drag profile, through-body tunnel thrusters have become a popular addition to modern AUV systems. The effect of forward vehicle motion and sideslip on these types of thrusters is not well understood. In order to characterize these effects and to adapt existing tunnel thruster models to include them, an experimental system was constructed. This system includes a transverse tunnel thruster mounted in a streamlined AUV. A 6-axis load cell mounted internally was used to measure the thrust directly. The AUV was mounted in Memorial University of Newfoundland's tow tank, and several tests were run to characterize the effect of vehicle motion on the transient and steady state thruster performance. Finally, a thruster model was modified to include these effects.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.461-461
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• 2000

Nonlinear pulse width modulation(PWM) controlled system is considered to achieve control performance of thruster-controlled spacecraft. The actual PWM controlled motions occurs, very closely, around the average model rajectory. Furthermore nonlinear PWM controller design can be directly applied to thruster controlled spacecraft to determine thruster on-time. Sliding mode control for attitude tracking of three-axis thruster-controlled spacecraft is presented. Simulation results are shown which use modified Rodrigues parameters and sliding mode control law to achieve attitude tracking of a three-axis spacecraft with thrusters.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.6
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• pp.1044-1055
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• 2015

DPCap analysis can assist in determining the maximum environmental forces the DP system can counteract for a given heading. DPCap analysis results are highly affected by the thrust forces provided by the thrust system which consists of several kinds of thrusters. The thrust forces and moment are determined by the maximum thrust of the thrusters as well as the thruster configuration. In this paper, a novel local optimization of thruster configuration based on a synthesized positioning capability criterion is proposed. The combination of the discrete locations of the thrusters forms the thruster configuration and is the input, and the synthesized positioning capability is the output. The quantified synthesized positioning capability of the corresponding thruster configuration can be generated as the output. The optimal thruster configuration is the one which makes the vessel has the best positioning capability. A software program was developed based on the present study. A local optimization of thruster configuration for a supply vessel was performed to demonstrate the effectiveness and efficiency of the program. Even though the program cannot find the global optimal thruster configuration, its high efficiency makes it essentially practical in an engineering point. It may be used as a marine research tool and give guidance to the designer of the thrust system.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.9
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• pp.1965-1971
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• 2010

A ship propulsion thruster platform which is used by safety sailing takes charge of remote control of a main engine in ship. This system not only guarantees safety and reliable flight sailing but also require remote control technology of a ship. Accordingly, in this paper it deals with a telegraph lever control unit system which is a part of propulsion thruster system as localization technology. Also it makes sure of knowledge and core technology through analysis and designing and developing a telegraph lever control unit system. Moreover, it is sure of acquisition of base technology for integration of a ship propulsion thruster platform.