Traditional approaches to AUV collision avoidance involve the adaptation of COTS electronic scanning sonars that have been designed for applications where low power is not a consideration. This has an adverse impact on the endurance and performance of the AUV. The navigation and obstacle avoidance processing is typically performed by the vehicle control processor, acting on large volumes of dat...

There is increasing concern that human-produced ocean noise is adversely affecting marine mammals, as several recent cetacean mass strandings may have been caused by animals' interactions with naval 'mid-frequency' sonar. However, it has yet to be empirically demonstrated how sonar could induce these strandings or cause physiological effects. In controlled experimental studies, we show that mid...

In this paper, we are interested in inferring the sources of various types of sonar features typically observed by a mobile robot. After a brief discussion of terrestrial sonar sensing, we develop a set of operators that associates arc-shaped features extracted from sonar scans with real world primitives. Our classi cation scheme is probabilistic and is based on empirical data: the condence of ...

Affected by the residual of time varying gain, beam patterns, angular responses, and sonar altitude variations, radiometric distortion degrades the quality of side-scan sonar images and seriously affects the application of these images. However, existing methods cannot correct distortion effectively, especially in the presence of seabed sediment variation. This study proposes a new radiometric ...

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...