Allseas, a global leader in offshore pipeline installation and subsea construction, is to take advantage of the performance and operational benefits available from Sonardyne International’s GyroUSBL acoustic positioning technology, following an order for two systems for its 236 metre long lay vessel, Lorelay.

Used in conjunction with a Ranger 2 USBL (Ultra-Short BaseLine) topside which also formed part of the order, the GyroUSBL transceivers will be installed on the end of the Lorelay’s stinger to acoustically track an ROV deployed to ensure a pipe is accurately touching down in the permitted corridor.

USBL transceivers are routinely deployed through the hull or over-the-side of a vessel, enabling targets to be tracked below, to the side and far behind. However, on a large DP pipelay vessel such as the Lorelay, a transceiver cannot reliably ‘see’ through the thruster wash created at the rear so touchdown monitoring operations are often conducted by an ROV operating from a survey vessel (equipped with its own USBL system) following on behind. With a stinger-mounted GyroUSBL, there is a proven alternative.

The unit combines a 6G HPT transceiver (either 5,000 or 7,000 model) and Lodestar Attitude and Heading Reference System in the same assembly and is supplied pre-calibrated to eliminate the mechanical alignment errors seen in conventional USBL setups. These features allow an acoustic transceiver to be sited well away from noise interference, even on a dynamic structure such as a stinger, and deliver outstanding positioning performance. It also means that a pipelay vessel is able to employ its own ROV to carry out touchdown monitoring, allowing the accompanying survey vessel to get on with another task, or eliminating the need for it altogether.

Mounting a GyroUSBL on a stinger is now a widely adopted practise amongst pipelay vessel operators, with the technique having first appeared on the market in 2013. The Lorelay will be third vessel in the Allseas fleet to be equipped in this way, with systems already in operation on the Audacia and Solitaire.

[blockquote author=” Alan MacDonald, Sales Manager at Sonardyne in Aberdeen “]”Locating a transceiver on the stinger is a great solution for ensuring that vessel noise disruption is rejected. The time-saving features of GyroUSBL results in reduced operational costs with the ability for users to move it from vessel to vessel with minimal downtime whilst maintaining the highest levels of positioning performance.”[/blockquote]

Limited by space, layout or weight? Don’t worry; our most popular navigation, tracking and modem products are now available in OEM form meaning you can package them in any way that best suits you.

Lodestar AHRS OEM/ SPRINT INS OEM (obsolete)

Our 3rd generation Lodestar and SPRINT mechanics addressed many users’ needs for a smaller and lighter form-factor. But sometimes, a vehicle such as a USV or AIV are so restricted on payload capacity, further size and weight savings need to be made. This can now be achieved with an OEM Lodestar or SPRINT. The lightweight aluminium housing of the SPRINT 500 model shown here measures just 202mm in diameter by 162mm tall.

Nano AvTrak 6 OEM

Small AUVs need small instruments and they don’t get much smaller than our new Nano AvTrak 6 OEM. It measures just 87.7mm long and 56mm wide but we’ve managed to pack in many of the features supported by the larger AvTrak 6 transceiver including; USBL tracking and two-way comms. A remote transducer gives you the flexibility to mount it anywhere, whilst the li-ion battery gives you 10 days standby life to help you recover the vehicle if it’s lost.

Syrinx DVL OEM

Syrinx is our 600 kHz Doppler Velocity Log (DVL). When fitted to your subsea vehicles and surface platforms, it’s capable of high altitude navigation that’s comparable to a 300 kHz DVL with the high resolution performance of a 1200 kHz DVL. In OEM form you will get a full depth rated, water blocked array that’s connected by cable to a separate electronics module. You can package this into your vehicle’s existing main subsea electronics, or re-package it in an entirely custom housing designed to meet your operational setup.

AvTrak 6 OEM

The lightweight rechargeable transceiver design of AvTrak 6 OEM allows for easy integration into autonomous vehicles and provides all of the features supported by the standard AvTrak 6 including; Sparse LBL ranging and Burn Wire. The OEM chassis can be customised to provide mounting points for specific vehicle internals and is supplied with a threaded boss mount MF Omni-directional transducer for easy mounting on a vehicle’s hull. The integrated li-ion rechargeable battery provides up to 30 days emergency standby life.

If you would like any more information on any of the products here, please get in touch with your local Sonardyne office.

Global subsea equipment specialist, Ashtead Technology has selected acoustic and inertial navigation technology from Sonardyne International Ltd. to add to its rental fleet. The multiple SPRINT-Nav systems will be made available to support survey and construction projects using ROVs and AUVs in water depths down to 4,000 metres.

SPRINT-Nav makes optimal use of acoustic aiding from data sources including USBL, sparse LBL and DVL and pressure sensors to improve the accuracy, precision and reliability of subsea vehicle navigation. Its all-in-one design tightly couples Sonardyne’s SPRINT inertial and Syrinx Doppler technologies to enable marine robotic platforms to remain precisely on course over many kilometres travelled, even if one or two DVL beams become unavailable.

The compact design of SPRINT-Nav’s titanium subsea housing is considered to be one of the smallest instruments of its type on the market. This ensures rapid and simple mobilisation on vehicles and an ideal choice for rental projects.

[blockquote author=” Ross MacLeod, Technical Director of Ashtead Technology “]”Our existing pool of acoustic and inertial navigation systems from Sonardyne have proven to be extremely popular with our customers and we have enhanced our rental fleet to meet their growing demands. This investment underlines our commitment to the subsea market, by offering the latest, most efficient technologies available and will see our clients experience a more cost-effective, reliable solution.”[/blockquote]

Dan Zatezalo, Sales Manager with Sonardyne said, “We’re delighted that Ashtead is the latest organisation to take delivery of SPRINT-Nav systems. We’re seeing more and more field development specifications around the world calling for our hybrid navigation solution which ultimately translates into projects being completed in less time and for less cost.”