SPRINT SYRINX 500
SPRINT is an acoustically aided Subsea Inertial Navigation system for subsea vehicles. SPRINT makes optimal use of acoustic aiding data from acoustic USBL and LBL positioning and other sensors such as Doppler Velocity Log (DVL) and pressure sensors.
Description
SPRINT is an acoustically aided Subsea Inertial Navigation system for subsea vehicles. SPRINT makes optimal use of acoustic aiding data from acoustic USBL and LBL positioning and other sensors such as Doppler Velocity Log (DVL) and pressure sensors. This improves position accuracy, precision, reliability and integrity while reducing operational time and vessel costs. The system extends the operating limits of Ultra- Short BaseLine (USBL) and can dramatically improve the operational efficiency of Long BaseLine (LBL). The new third generation SPRINT unit offers power pass-through to aiding sensors, reducing cabling and interfacing complexity.
SPRINT INS shares the same hardware platform as Lodestar AHRS and is a combined AHRS (Attitude Heading Reference System) and AAINS (Acoustically Aided Inertial Navigation System). Running both the AHRS and INS algorithms concurrently allows inertial navigation to start or restart instantaneously on receipt of a position update as the AHRS seamlessly provides orientation to the INS on start-up. This avoids the lengthy ‘alignment’ period common to other INS systems. Thereafter, the separate AHRS and INS computed orientation are autonomously monitored as an indication of system health.
All AHRS and AAINS computations are performed within the Lodestar, making the system robust and resilient to communications issues. Lodestar maintains a rolling 15 day backup of all real time navigation and raw data on an onboard SD card which can be retrieved if required. Coupled with concurrent logging of all data by the topside software, data integrity is ensured.
Syrinx combined unit – DVL and AHRS / INS
Syrinx provides tight beam-level aiding to SPRINT INS that allows for unprecedented DVL positioning performance and can continue to operate even if one or two DVL beams are unavailable. Standalone 3rd generation Lodestar and SPRINT units are engineered to mechanically ‘mate’ with Syrinx DVL using matching endcap alignment dowels. This provides the performance and space benefits of pre-calibrated and repeatable inertial and DVL but either unit can be swapped out.
For the ultimate integration, Lodestar/SPRINT and Syrinx are also now available as a single combined unit. The result is one of the smallest inertial DVL instruments available on the market. Available with an optional internal intelligent pressure sensor it provides a single unit for almost any ROV and survey task. In the combined unit, each Syrinx transducer has a full depth rated water block to ensure protection of the internal components. When supplied together, most combinations of Lodestar/SPRINT and Syrinx are unlikely to require a re-export licence, making shipping easier.
Technical information
SPRINT 300
Heading | Accuracy (Secant Latitude) | 0.2º (Lodestar AHRS) <0.1º (SPRINT INS) |
Settle Time | <15 minutes in dynamic conditions (Lodestar AHRS) Instantaneous (SPRINT INS) |
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Follow Up Speed | 900º / second** | |
Roll and Pitch | Accuracy | 0.1º (Lodestar AHRS) <0.05 º (SPRINT INS) |
Maximum Acceleration | 10.0 g** | |
SPRINT Aided INS | Aiding Supported | USBL, Depth, DVL, Zero Velocity, Manual Position |
USBL Aided | 2 times improvement in precision over ‘raw’ USBL | |
USBL and DVL Aided | 3-6 times improvement in precision over ‘raw’ USBL | |
DVL Aided Accuracy | 0.25% position error for distance travelled |
SPRINT 500
Heading | Accuracy (Secant Latitude) | 0.1º (Lodestar AHRS) 0.04º (SPRINT INS) |
Settle Time | 5 minutes in dynamic conditions (Lodestar AHRS) Instantaneous (SPRINT INS) | |
Follow Up Speed | 900º / second** | |
Roll and Pitch | Accuracy | 0.01º |
Maximum Acceleration | 10.0 g** | |
SPRINT Aided INS | Aiding Supported | USBL, Depth, DVL, Zero Velocity, Manual Position, LBL |
USBL Aided | 3 times improvement in precision over ‘raw’ USBL | |
USBL and DVL Aided | 4-10 times improvement in precision over ‘raw’ USBL | |
DVL Aided Accuracy | 0.1% position error for distance travelled |