Motion compensation of AUV-based synthetic aperture sonar

Abstract

To date, ocean-going synthetic aperture sonar (SAS) systems have been deployed exclusively in a configuration where the sonar instrument is housed in a towed body that receives power from and exchanges information with the vessel to which it is attached. Meanwhile, recent years have witnessed the beginnings of maturity with respect to both SAS and autonomous underwater vehicle (AUV) technologies. In order to move away from the towed sonar paradigm, the Coastal Systems Station has recently taken delivery of and begun using the first AUV-based SAS. The AUV was manufactured by Bluefin Robotics and the sonar used on this vehicle is the existing CSS LF/HF SAS. This transition is not without its challenges, however, as the operation and dynamic behavior of an AUV is different from that of a towed body. In general, the AUV configuration makes the problem of unwanted platform motion more severe and more difficult to solve. This paper discusses motion compensation in the context of initial evaluations of the performance of the CSS AUV-based SAS system.

Synthetic Aperture Sonar: The Past, the Present and the Future

“…Led by Christoff [38] and a part of the MUDSS programme they where the first to have a two-band simultaneous SAS imaging system. This SAS has now matured into a well-tried system [39,40] that has recently been moved from a cable-towned platform to an AUV [41][42][43]. Also joining the fray was a group based at University College London (UCL) led by Griffiths and DERA (but now part of QinetiQ) led by Chapman.…”

Simulation of Rippled-Sand Synthetic Aperture Sonar Imagery

“…The images presented here have a resolution of Δx slant ≈ 5.8 cm by Δy SAS ≈ 2.0 cm corresponding to slant-range and along-track respectively, and collected at a center frequency of 120 kHz. A more complete description of the experiments conducted with, and development of, the SSAM system can be found in [21][22][23][24][25][26].…”

Progress in the development of buried minehunting systems

“…The BBSAS has been successfully tested onboard CSS's advanced sensor tow vehicle [6]. Recently SAS21 was integrated into the Reliant AUV and has undergone its first series of sea tests [7]- [8]. A photograph of this sea-going system is shown in Fig.…”