BRIDGES Miniaturised Acoustic Smart Sensor

Descriptions

Development of a miniaturised acoustic smart sensor falls under BRIDGES WP5, Task 5.4 lead by NOC. The deliverable will be the design and build of a suitable system with accompanying documentation to support system integration into the glider being designed under the BRIDGES project. This task will integrate a sensor payload targeted to support surveillance of sea-bed mining activities to monitor the impact of discharges of the unwanted debris and to determine nodule characteristics and associated substrate. We require an acoustic specialist to design and build a miniaturised acoustic sensor suitable for installation on the D and UD vehicles (to 5000m depth). This low-power, low-range sensor will be used for purely scientific purposes to characterise sea-bed sediment properties. The miniaturized acoustic smart sensor will be designed to obtain information on sea bottom sub-surface layers. The sensing package will consist of: a set of transducers and hydrophones for acoustic transmission and reception in the frequency range of 10-30 KHz; a programmable wideband signal generator; a low power and low noise acquisition system and a set of processing algorithms to extract the different acoustic impedances and sound speed profiles of the sea-bottom layers with a penetration up to 10 meters. Technical requirements to allow integration with the BRIDGES glider are given below: Maximum power consumption during sampling: 25W Total sampling time at bottom of dive no more than: 1 minute @ 25W Power should be kept to a minimum to maximise deployment time. Discrete operation enabled/disabled by external input Communications: Ethernet TCP/IP and/or RS232 Optional PPS TTL signal from glider control for time synchronization Externally supplied power, max supply voltage: 48V Data storage on board (approx. 500 Gb) Comprehensive technical documentation (including manuals, schematics, data sheets, interface protocols and other as required) Physical size and weight to be suitable for Glider operations. It is expected that the glider will have a total maximum wet payload weight of approx. 5Kg . Maximum Operating depth : 5000m