Jinyeong Park

An AUV (Autonomous Underwater Vehicle) being able to dock without surfacing to a launcher or an underwater station can give us long-time duration. It is important for the AUV to be guided to the dock safely. This paper introduces a test bed platform AUV named ISiMI and her optical terminal guidance system. ISiMI uses the optical terminal guidance system for underwater docking. The guidance system consists of a hardware part and a software part. One CCD camera and a frame grabber constitute the h

Various configurations of underwater docking stations have been developed during the last two decades. In this paper, five parameters are suggested to specify characteristics of the docking stations. And then, we describe docking problem using the five parameters. Unidirectional approach for docking of an under-actuated AUV (Autonomous Underwater Vehicle) is considered and effects of drift caused by ocean currents are introduced. To compensate the effect, modified linear terminal guidance and a

We report on highly stretchable polymer dispersed liquid crystal (PDLC)-based smart windows using Ag nanowires (NWs) and conductive PEDOT:PSS hybrid electrodes. By bar coating a Ag NW and PEDOT:PSS mixed ink on a transparent and stretchable polyurethane (PU) substrate, we fabricated highly transparent and stretchable hybrid electrodes with a sheet resistance of 40 ohm per square, an optical transmittance of 82%, and a stretchability of 30% to replace conventional brittle ITO electrode. Bending a

Vision guided underwater docking algorithm for an AUV (autonomous underwater vehicle) and a small test-bed AUV named ISiMI have been developed in KORDI (Korea Ocean Research and Development Institute). Underwater experiments were conducted in the previous research. The developed algorithm was based on pure pursuit guidance law. There is an absence of compensation against environmental disturbance, especially ocean current. Moreover, no alignment of the AUV's heading with dock direction was appli

Unidirectional docking of a torpedo-type underactuated AUV (Autonomous Underwater Vehicle) has been developed. In this paper, guidance scheme considering drift caused by ocean currents will be investigated. To compensate drift, we design an ocean current observer. The observer is based on kinematic equations of the AUV. We also suggest a guidance scheme based on linear terminal guidance using the observer. The LTG (Linear Terminal Guidance) is in the framework of optimal control but there is no

A blue laser annealing process was investigated to improve the connectivity of slot die-coated Ag nanowire (NW) network electrodes intended for use in flexible and transparent thin film heaters (TFHs). The electrical, optical, and morphological properties of blue-laser-irradiated Ag NW network electrodes were investigated as functions of the scanning speed apllied during annealing. Due to effective welding of Ag NWs that were formerly under only physical contact, and due to complete removal of t

In west coast of Korea peninsula, there are some offshore sites where ancient sunken shipwrecks have been discovered. These ships are supposed to carry an amount of artifacts what show lifestyle and culture of the day. In these areas, however, because of fast ocean currents and low visibility, underwater survey and excavation by divers are strictly restricted. Especially, optical cameras and human's visual inspection become defective. To overcome these conditions, use of unmanned underwater vehi

In this paper, head alignment of a single-beam scanning sonar installed on a multi-legged underwater robot is described. The multi-legged underwater robot is supposed to survey seafloor, underwater structures, etc. Typical optic cameras, however, are not appropriate to show high quality scenes in a turbid water. Therefore, to collect images in a low visible underwater environment, the single-beam scanning sonar is proper and installed on the back of the robot. To collect sonar images without dis

A deep-sea Remotely Operated Vehicle(ROV) which has six artificial and articulated legs has been developed by Marine ICT Research Division in Korea Research Institute of Ships & Ocean Engineering (KRISO) since 2015. The maximum operating depth of this ROV is 6,000m and its name is Crabster CR6000. The CR6000 system has adopted typical two-body system which comprises CR6000 itself and one shuttle which does not only play a role as a depressor or a launcher but also carries the CR6000. In this pap

Of late, demand for sites and platforms to test the performance of marine equipment and underwater and surface robots during the development process has been increasing in South Korea. The Korea Research Institute of Ships and Ocean Engineering(KRISO) has performed unit performance and overall performance tests at the Jangmok wharf in Geoje-si, where the South Sea Research Institute (SSRI) of the Korea Institute of Ocean Science and Technology (KIOST) is located, and engaged in the development o

In this chapter, development of a test-bed AUV is described. Free running test and vision guided docking are also presented. Autonomous underwater vehicles (AUVs) have become a main tool for surveying below the sea in scientific, military, and commercial applications because of the significant improvement in their performance. Despite the considerable improvement in AUV performance, however, AUV technologies are still attractive to scientists and engineers as a challenging field. For example, mu

Crabster CR200 is a remotely operated vehicle which has six artificial and articulated legs driven by BLDC motors. It is supposed to walk on the sea floor. As a result, the robot has a very complicated appearance and hydrodynamic forces and moment acting on the robot experience a variety of changes according to configurable legs and body postural position. This paper describes the experiments to estimate lift force, drag force and pitching moment acting on CR200 using a 1/4 length ratio scaled m