Sonardyne UK (Head Office)
T. +44 (0) 1252 872288
F. +44 (0) 1252 876100
E. sales@sonardyne.com
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.
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.
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.
Key Features
•
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
•
MTBF RLG >100,000 hours
MTBF Lodestar >50,000 hours
•
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. sales@sonardyne.com
www.sonardyne.com
Specifications
Lodestar- Attitude & Heading Reference System (Subsea)
205mm
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
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
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
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
Specifications subject to change without notice - 02/2009