Description
Lodestar 200 is a combined solid state Attitude and Heading Reference System (AHRS), which is upgradable to SPRINT Acoustically Aided Inertial Navigation System [AAINS]. The unit is comprised of three high grade, high reliability, commercially available, Ring Laser Gyros (RLG) and accelerometers. The sensors are also the standard for commercial aviation with a proven 15+ year track record. Lodestar 200 AHRS provides heading, pitch, roll accuracy and settle time that is class leading in the low-cost north seeking subsea AHRS category. It requires no external aiding and can settle in <15 minutes or less in dynamic conditions. On-board data storage and backup battery functionality ensures continued operation and no data-loss even if communications or external power is lost. Lodestar 200 AHRS is designed for subsea vehicle integration and provides industry standard gyrocompass for simple interfacing. In addition, advanced outputs such as acceleration and rotation rates are also provided to support ROV autopilot and station keeping functions. Lodestar 200 AHRS has built-in field upgradability to the higher performance Lodestar 300 AHRS and SPRINT 300 aided INS. This feature allows operators to equip their vehicles with a cost effective AHRS at vehicle assembly whilst ensuring commercial and operational flexibility to upgrade as and when needed in the field. The optional SPRINT upgrade provides a dual algorithm capability, which is unique in the market and allows for dual use from one inertial instrument, e.g. Lodestar AHRS for ROV, SPRINT INS for Survey teams.
Specifications
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Other specifications
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Graphical user interface
Y
Typical application
Acoustical Aided INS for high accuracy survey; subsea metrology and DP. IMO certified AHRS.
Distinguishable features
Customised for reliable use in commercial marine applications and for optimal integration with acoustic positioning systems.
Export restrictions
US Commerce controled
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Environmental
-
Non-operating shock tolerance [g]
22
Operating shock tolerance [g]
10
Max. rotation speed [deg/s]
500
Min. operating temperature [°C]
-10
Max. operating temperature [°C]
55
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Software
-
Name
Lodestar
Filtering
Y
Adaptable filter strength
Yes
Adaptable input signals
Y
Integrity monitoring of position input
Y
Integrity monitoring of log input
Y
Max. number of position input signals
3
Max. number of log input signals
1
Maximum latency of position input [ms]
10000
Uncertainty indicators given in output
1DRMS; 1sigma RMS; error ellipse; etc
Uncertainty of time stamp for output [ms]
0.001
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Doppler log aided uncertainty
-
Heading [deg]
0.1
Pitch [deg]
0.01
Roll [deg]
0.01
Heave [m]
0.02
-
GNSS aided uncertainty
-
Heading [deg]
0.04
Pitch [deg]
0.01
Roll [deg]
0.01
Heave: constant part [m]
0.05
Heave: variable part [%]
5
Surge/sway [m]
0.05
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General
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Height [m]
0.26
Width [m]
0.205
Length [m]
0.205
Weight [kg]
18.5
Min. Voltage (DC)
20
Max. Voltage (DC)
50
Power consumption [W]
15
Splashproof casting
Y
Water resistant casting
Y
Water resistance [m]
6000
Mean time between failures [hr]
400000
Type of accelerometer
Closed-loop (force feedback) Q-Flex
Type of gyro
Ring Laser Gyro (RLG)
Removable from base plate
Y
Type of application
Marine
Moving parts
N
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EM log aided uncertainty
-
Heading [deg]
0.1
Pitch [deg]
0.01
Roll [deg]
0.01
Heave [m]
0.05
Surge/sway [m]
0.05
-
Unaided uncertainty
-
Heading [deg]
0.1
Pitch [deg]
0.01
Roll [deg]
0.01
Heave [m]
0.05
-
Data formats
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NMEA formats
GGA; GLL; ZDA; VTG; ACK; HDT; THS; TXT; ALR
Other
binary and ASCII messages
-
Inertial Measurement Unit
-
Accelerometer bias [µ-g]
200
gyro bias [deg/hr]
0.01
Calibration procedure
IMU is factory calibrated - no user calibration required. DVL calibration procedure supplied
