Page 36: of Marine Technology Magazine (May 2020)

FEATURE Vehicles/IMR or 3 dynamically positioned (DP) vessel. tery, powering six 500W thrusters and optimAL nAvigAtion

DP is needed in order to be able to enter enabling it to work for eight hours, or to

AnD positioning the 500 m platform exclusion zones in cover about 10 km per dive (or 30 km per

Key to enabling a level of autonomy for order to follow pipeline systems all the day) at speeds of about 1.4 km/hr (0.75 the vehicle is having a reliable and ac- way up to the platform base. But DP ves- knots), with speeds in excess of 2.16 km/ curate navigation solution, so it knows sels can be costly. hr (>1 knot) possible. The goal is to have where it is. Sonardyne technologies have

The Xplorer AUV solution provides a vehicle able to travel 100 km, i.e. out been chosen, specifcally Sonardyne’s an untethered and more autonomous ve- 50 km and back 50 km, says Sompol, as SPRINT inertial navigation system hicle, which can be launched and tracked well as being able to work down to 200 (INS) and Syrinx Doppler velocity log from a lower class, and typically smaller, m water depth. (DVL). SPRINT is an acoustically aided therefore less costly vessel that doesn’t The payload also includes a video cam-

INS which makes optimal use of acoustic need to go into the exclusion zone – and era (SubC Imaging), an EFG probe (Pola- aiding data from acoustic inputs, includ- so doesn’t require the higher DP rating. trak), multibeam sonar (Imagenex) for ter- ing Ultra-Short BaseLine (USBL) and “With this method, we can use a small rain mapping and to support the pipeline Long BaseLine systems, as well as DVLs vessel which saves operational cost com- tracking functionality and multibeam for- and pressure sensors. pared with using a work class ROV or us- ward looking sonar (Teledyne BlueView).

The 600 kHz Syrinx DVL offers a wide ing a larger vessel,” says Sompol HiveGround’s plans also include close operating range – from 0.4 m to 165 m

The Xplorer’s initial 300 m depth-rated range visual inspection and mechanical – with the velocity resolution of a high vehicle payload included a 10 kWh bat- inspection such as a CP probe.

frequency DVL, making it hugely versa-

HiveGround May 2020 36

MTR