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Lee, Jae-Yong
- Journal of Ocean Engineering and Technology
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- v.26 no.3
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- pp.6-12
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- 2012
In this paper, addressed is the control problem of generating a formation for a group of unmanned surface and underwater vehicles. The formation control scheme proposed in this work is based on a fusion of theleader-follower and virtual reference approaches. This scheme gives a formation constraint representation that is independent of the number of vehicles in the formation and the resulting control algorithm is scalable. One of the most important features in controller design is the ability of the controller to globally and exponentially stabilize the formation errors defined by the formation constraints. The proposed controller is based on feedback linearization, and the formation errors are shown to be globally and exponentially stable in the sense of Lyapunov.
https://doi.org/10.5574/KSOE.2012.26.3.006 인용 PDF KSCI

Lee, Kwi-Joo;An, Jung-Sun
- Journal of Ocean Engineering and Technology
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- v.26 no.3
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- pp.1-5
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- 2012
A complex energy saving device has been developed for middle class vessels. The propulsive performance of the developed device is described through a model test. The pre-swirl stator, which recovers the rotational energy of the propeller slipstream, is a well-known energy saving device for large vessels. The pre-swirl stator for a large vessel is usually cast as a part of the stern frame and has a high cost. The manufacture of a cast stator for an existing vessel is almost impossible. The complex device that was developed can be fitted on astern frame by welding. The model tests show a 4-6% efficiency gain for middle class vessels with the developed appendages compared to those with bare hulls.
https://doi.org/10.5574/KSOE.2012.26.3.001 인용 PDF KSCI

Seo, Dae-Won;Lee, Se-Jin;Oh, Jungkeun
- Journal of Ocean Engineering and Technology
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- v.30 no.1
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- pp.18-24
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- 2016
Stabilizer fins are installed on each side of a ship to control its roll motion. The most common stabilizer fin is a rolling control system that uses the lift force on the fin surface. If the angle of attack of a stabilizer fin is zero or the speed is zero, it cannot control the roll motion. The Coanda effect is well known to generate lift force in marine field. The performance of stabilizer fin that applies the Coanda effect has been verified by model tests and numerical simulations. It was found that a stabilizer fin that applied the Coanda effect at Cj = 0.085 and a zero angle of attack exactly coincided with that of the original fin at α = 26°. In addition, the power needed to generate the Coanda effect was not high compared to the motor power of the original stabilizer fin.
https://doi.org/10.5574/KSOE.2016.30.1.18 인용 PDF KSCI KPUBS HTML