Sonardyne UK (Head Office) T. +44 (0) 1252 872288 F. +44 (0) 1252 876100 E. [email protected] www.sonardyne.com Datasheet Lodestar – Attitude & Heading Reference System (Subsea) Description Lodestar is a solid state IMO approved Attitude and Heading Reference System (AHRS). The unit is comprised of six sensing elements, three Ring Laser Gyros (RLG) and three linear accelerometers, running a Sonardyne developed gyrocompass algorithm. Incorporating a rugged housing, Lodestar AHRS can be supplied to suit any depth of subsea application. With a battery back up capability supplied as standard, the unit is able to continue to communicate attitude during vehicle brown-outs. Pole mounted applications can provide a more accurate solution to the multibeam or USBL operation. The Lodestar AHRS utilizes a genuine gyrocompassing algorithm capable of precise heading, roll and pitch estimation in dynamic conditions without the need for external aiding inputs or vessel manoeuvres. Lodestar also applies a heave algorithm to the vertical motion of the unit resulting in a robust heave measurement solution. Therefore, the Lodestar product is suitable for any application that requires the accurate measurement of heading, heave, roll, and pitch in a highly dynamic environment. Key Features Where high accuracy and a risk free solution is required, the Lodestar AHRS is an ideal replacement for the motion sensor and gyrocompass package, due to its dynamic capability and fast spin up time. • MTBF RLG >100,000 hours MTBF Lodestar >50,000 hours The Sonardyne Lodestar has been designed with reliability as a priority. The unit comprises of high grade, commercially available, IMU components with a very high meantime between failure (MTBF). Lodestar is compatible with all Sonardyne LBL and USBL products, as well as multiple applications in the offshore and survey marketplace. • Single box solution for motion sensor and gyrocompass • 0.1º heading accuracy • 0.01º roll and pitch accuracy • <5 minute settling time • 5cm / 5% heave accuracy • Fast follow up speed of 500º / sec • Choice of depth ratings: 1,000 3,000 and 5,000 metres • Surface version available • Transport approved Li-Ion battery back up as standard • Internal 4GB memory allows post processing of a 2 day mission • Designed and approved to IMO Resolution A424(XI) • Ethernet interface • INS ready Sonardyne UK (Head Office) T. +44 (0) 1252 872288 F. +44 (0) 1252 876100 E. [email protected] www.sonardyne.com 205mm Specifications Lodestar- Attitude & Heading Reference System (Subsea) 330mm 358mm Feature Depth Rating Physical Size Weight in Air / Water Mechanical Construction Type 8084-000-11 1,000 metres 205mm Dia. x 358 mm 13.9kg / 2.9kg Anodised Aluminium Specifications Common To All Type 8084 Subsea Lodestar Units. Attitude Heading Range Accuracy Settle Time Follow Up Speed Resolution Roll & Pitch Range Accuracy Resolution Heave Range Accuracy (Real Time) Bandwidth Resolution Environmental Operating Temperature Shock Rating Operational Power Requirement Back Up Battery Type / Life Data Storage Digital Output Number of Digital Ports/Protocol Other Ports Optional INS Upgrade Path Navigation Error (Free Inertial) Maximum Acceleration Specifications subject to change without notice - 02/2009 Type 8084-000-16 3,000 metres 220mm Dia. x 425mm 22kg / 8kg Anodised Aluminium Type 8084-000-21 5,000 metres 205mm Dia. x 409mm 39kg / 28kg Super Duplex S/Steel 0-360º 0.10º secant latitude rms <5 minutes 500º / second 0.01º ±180º (No physical limit) 0.01º 0.01º ±99m 5cm or 5% (Whichever the greater) User selectable 0.01m -10°C to +55°C 22g, 11ms half sine 18 – 50V DC, 15W nominal, 20W peak Li-Ion / 3 hours 4GB internal memory 4 Digital Ports / RS232 or RS485 1 × Ethernet Yes >1.5NM/hr CEP 2.5g