Products > Fetch - Wireless Autonomous Sensor Logging Node

Overview: Fetch is a long-life subsea sensor logging node that enables data to be wirelessly extracted via its integrated high speed acoustic modem. It can be free fall deployed to the seabed and will land in an upright position. This reduces deployment time and cost.

Fetch can be configured with an array of different sensors dependent on the monitoring application. Standard sensors include high accuracy pressure, temperature and sound velocity as well as inclination. Other sensors can be integrated internally or externally as required.

The ultra-low power platform powers up sensors only when required and logs and timestamps the data to an SD memory card.

The sampling regime can be configured serially before deployment and via the acoustic modem which is also used to recover the data to the surface. The 6000 bits per second modem transfer rate enables data to be extracted in minimal vessel time so reducing operational costs.

High capacity primary alkaline or lithium battery packs enable deployments of many years, dependent on sensor selection and sampling rate.

Fetch is compatible with Sonardyne’s Ultra-Short BaseLine (USBL) positioning systems for positioning during deployment/recovery. When the mission is complete, Fetch can be acoustically commanded to release from its stand and return to the surface under its own buoyancy ready for collection.

Key Features: Autonomous sensor logging with acoustic telemetry of data; Low cost free fall deployment; Low data recovery costs; Long life – up to 5 years with excellent corrosion resistance; Flexible 100 to 6000 bits per second Wideband 2 acoustic telemetry modem; Fully configurable logging through surface software; USBL positioning compatible; Integrated acoustic release

Feature	Type 8306
Depth Rating	3,000 or 6,000 Metres
Operating Frequency	MF (Omni or Directional) or LMF (Omni or Directional)
Battery capacity / life	221Ah / 5 years typical (dependent on sensors and sampling interval)
Serial Communications	RS232 (Full-Duplex) or RS485 (Half-Duplex)
Mechanical Construction	Glass sphere, Galvanised Stand, Duplex S/Steel Guards and Connectors
Weight in Air	Mechanical Construction Duplex Stainless Steel housing and reference plate. AGP connector.
Weight in Water	Fetch: 40 kg, Stand: 60 kg
Weight in Air	Fetch: 10 kg Up Thrust Stand: 40 kg
Sensor Options	TCurrent version - Temperature compensated Strain Gauge or Paroscientific DigiQuartz pressure sensor and/or, Presens Precise and Platinum Resistance Thermometer and MEMS inclinometer. Optional - sound velocity, turbidity and conductivity. Other sensors can be integrated as required or added externally.
Transmit Source Level – Vertical	190-202dB
Receiver Threshold	85dB
Connector Type	Impulse LPMIL-8-MP

Subsea Positioning, Inertial Navigation, Wireless Communications