Successful trials of SeaCat in a hybrid mode with different trailing antennas

01 Oct, 2014 00:00

From 22nd to 26th September, final trials with the ATLAS SeaCat AUV and the Digital Thin Line Array (DTLA) provided by the National University of Singapore/Acoustic Research Lab (NUS-ARL) in cooperation with the German Underwater Acoustics and Marine Geophysics Research Institute, the Technical Center of the German Army and ATLAS ELEKTRONIK were conducted on the torpedo test ground in Eckernförde.

Since 2013, ATLAS dealt with the question, if and if yes, how an AUV can contribute to the future anti submarine warfare and harbor security. To further examine operational scenarios, Ms. Stephanie Kemna was gained as a partner from the Center for Maritime Research of the NATO.

Key technologies and sensors were identified, such as a trailing sonar for passive and bi-static target detection. Since ATLAS haven't had a DTLA in their portfolio before, a technology cooperation was founded with NUS-ARL.

NUS-ARL provided two DLTAs. The first array was 21.7m long with 12 evenly spread hydrophones and a diameter of 15 mm. The second one had a length of 42.5m with 10 unevenly spread hydrophones and a diameter of 15mm. Both arrays could be operated with a frequency band up to 12 khz. A load capacity electronic was integrated in the SeaCat SwapHeadTM.

After the initial launch of the whole system on the ATLAS test ground, it was found that the intersection of tension cable and antenna was broken. Two ATLAS employees assitsted the NUS-ARL team with the repair work so that the trials could be conducted as planned.
During the trial, three missions were run up to a duration of 3 hours each.
At the same time, reference signals were received by a test transmitter from a trial boat.
Back on land, Automatic Identification System (AIS) and Ambient Noise-Data were analyzed to evaluate the DTLA's performance.
 
In conclusion, it was found that the SeaCat is capable of carrying a big sensor like the DTLA over a long period of time. The cooperation partner were highly impressed by the SeaCat's capabilities, the easy configuration with additional payloads and the reliability of the ATLAS AUV.
The performance of the sensor was not evaluated so far, as the data has to be analyzed by Marine Hyrdoacoustic Institute first, before it will be published.