The authors present a novel procedure for the automated rectification of side-scan sonar images. The traditional assumption of a flat seabed for the computation of the ground projection from the slant-range sonar data can later result in difficult geo-referencing and registration problems. Accurate rectification using actual seabed topography is required for precise integration of side-scan ima...

Buoyance forces are part of the fundamental physical resistances that act on moving or swimming objects in the ocean environment. For the case of multi-legged robot, such as hexapod walking on the seabed, buoyance affects the horizontal stability if the motion of the robot’s foot does not have sufficient force to step on the bottom of the seabed. Therefore, this study is carried out by integrat...

Theoretical ecology predicts that heterogeneous habitats allow more species to co-exist in a given area. In the deep sea, biodiversity is positively linked with ecosystem functioning, suggesting that deep-seabed heterogeneity could influence ecosystem functions and the relationships between biodiversity and ecosystem functioning (BEF). To shed light on the BEF relationships in a heterogeneous d...

This paper presents a proposed adaptive impedance control that derived based on Center of Mass (CoM) of the hexapod robot for walking on the bottom of water or seabed. The study has been carried out by modeling the buoyancy force following the restoration force to achieve the drowning level according to the Archimedes’ principle. The restoration force need to be positive in order to ensure robo...

The physical processes involved in the wave–seabed–mono-pile interactions are rather complex, and its upper lower structures affected by different loads. This paper presents application of a three-dimensional numerical model, which was validated with laboratory experiments available literature. First, soil response induced combined wave current around mono-pile is discussed, then stability pile...

Most multibeams today provide a measure of the received seabed backscatter intensity. With proper radiometric and geometric reduction, the seabed backscatter strength and its angular variation may be derived, which can then be used to attempt seabed classification. Most multibeams, however, are monochromatic in the sense that they transmit using a single center frequency (even if with some puls...

Offshore wind farms with high installed capacities and located further from the shore are starting to be built by northern European countries. Furthermore, it is expected that by 2020, several dozens of large offshore wind farms will be built in the Baltic, Irish and North seas. These wind farms will be constituted of a considerable number of turbines packed together. Due to shadowing effects b...

carbonate materials are mostly found in tropical areas, where exploiting gas and oil resources are of high concern. their unique behavior under shear loading first was recognised during oil resources investigations in the persian gulf. off-shore structures have been placed on carbonate soils which are highly crushable.during storms cyclic loading imposes on the bases of structures lied down on ...

Propagation and reverberation of acoustic fields in shallow waters depend strongly on the spatial variability of seabed geoacoustic parameters, and lack of knowledge of seabed variability is often a limiting factor in acoustic modeling applications. However, direct sampling (e.g., coring) of vertical and lateral variability is expensive and laborious, and matched-field and other long-range inve...

UWB pulse radars that offer target shape estimation are promising as imaging techniques for household or rescue robots. We have already proposed an efficient algorithm for a shape estimation method SEABED which is a fast algorithm based on a reversible transform. SEABED extracts quasi wavefronts from received signals with the filter that matches the transmitted waveform. However, the scattered ...