There has been an increasing interest in studying animal behaviours [1]. In the EU funded project “ChiRoPing: Developing Versatile and Robust perception using Sonar Systems that Integrate Active Sensing, Morphology and Behaviour” [2], the interest is placed on Chiroptera (bats) as bats are the nature’s expert in active sonar sensing [3]. Study of bats’ behaviour is not only of biological intere...

UNITES is a unique, interdisciplinary team with expertise spanning the environment (physical oceanography and bottom geology), ocean acoustics (propagation, ambient noise, reverberation and signal processing), and tactical sonar systems. The overall goals of the research are to enhance the understanding of the uncertainty in the ocean environment (including the sea bottom), characterize its imp...

This paper proposes an original method for the 3-D reconstruction of seabed from multiple sidescan sonar images. The proposed method adopts a stereo-like vision approach based on a combination of the GPS positioning and the image matching technology to correspond among multiple sidescan sonar images taken from different viewmints. and then estract the 3-D structure information of 'seabed from t...

An advanced sonar sensor produces accurate range and bearing measurements, classifies targets and rejects interference with one sensing cycle. Two advanced sonar systems are used to simultaneously localise and map an indoor environment using a mobile robot. This paper presents the approach and results from on-the-fly map building using a Kalman filter and a new odometry error model that incorpo...

Autonomous underwater vehicles (AUVs) are typically used to “actively” probe the ocean, using sensors that are mounted on a vehicle that moves through the water column. A more challenging task is to use an AUV to position a bottom-mounted stationary platform, such as a passive sonar that requires a large aperture. This paper describes the development of a passive sonar, which was mounted as a p...

Robotics research is dependent on intelligent, fast, accurate, reliable, and cheap sensors. Sonar sensing can fulfill these requirements. Moreover, sonar physics provides robotics researchers with a natural selection capability for landmark detection in navigation problems. This paper presents a new sonar system that produces accurate measurement and on-the-fly single cycle classification of pl...

Most marine mammal- strandings coincident with naval sonar exercises have involved Cuvier's beaked whales (Ziphius cavirostris). We recorded animal movement and acoustic data on two tagged Ziphius and obtained the first direct measurements of behavioural responses of this species to mid-frequency active (MFA) sonar signals. Each recording included a 30-min playback (one 1.6-s simulated MFA sona...

Some of the differences between broadband and narrowband sonar systems applied in fisheries hydroacoustics are examined. Following a brief discussion of the advantages and disadvantages of broadband sonar, three different aspects of narrowband and broadband sonar systems are compared: detection, Doppler processing, and split-beam localization. Summaries are provided that compare representative ...

The estimation of geometric structure of objects located underwater underpins a plethora of applications such as mapping shipwrecks for archaeology, monitoring the health of coral reefs, detecting faults in off-shore oil rigs and pipelines, detection and identification of potential threats on the seabed, etc. Acoustic imaging is the most popular choice for underwater sensing. Underwater explora...