The SeaTrac system is designed to deliver reliable, real-time location tracking for underwater assets. Its positional accuracy is shaped by two key components: range accuracy and angular accuracy.
This guide provides valuable insights into the results you can expect from USBL positioning and offers practical tips to optimise the performance of your SeaTrac system.
Range Accuracy: Sound Velocity Matters
The SeaTrac system’s range accuracy hinges on the speed of sound in water, a variable directly impacted by the water's salinity. Since salinity can differ based on factors like location and depth, understanding and accounting for this is essential. SeaTrac provides two ways to account for sound velocity in water:
- Automatic Calculation: SeaTrac can autonomously calculate the speed of sound in real-time based on current conditions.
- Manual Input: Users can also manually input a specific speed of sound if a known, accurate value is available.
With an accurate sound velocity value, the system can achieve range accuracy within a tolerance of +/- 0.1 meters.
Angular Accuracy: Heading and System Interference
Angular accuracy in SeaTrac is rooted in its heading sensor, which has a baseline accuracy of +/- 1 degree. However, in real-world conditions, the system often achieves an angular accuracy of +/- 5 degrees. This difference is largely due to interference from internal components which can slightly impact the heading accuracy.
Environmental Impact on Accuracy
To optimise the performance of your SeaTrac system in challenging underwater environments, consider the following strategies to mitigate the impact of natural factors:
Water Column Depth:
- Operate at depths within the recommended range for your system to maintain signal strength.
Channel Width:
- Avoid operating in narrow channels if possible, as signal reflections can cause errors.
- If narrow channels are unavoidable, position the system to minimise reflective interference, such as placing transceivers away from steep walls or obstructions.
Seabed Material:
- Be aware of the seabed composition in your operational area, as rocky or uneven terrain can scatter acoustic signals.
- Calibrate the system to adjust for the local seabed characteristics, ensuring better signal interpretation.
Wave Conditions:
- Plan operations during calmer weather to minimise signal distortion caused by rough water.
- Use stabilisation techniques, such as deploying the transducer on a fixed structure or pole.
By understanding and accounting for these environmental factors, you can improve the reliability and accuracy of SeaTrac’s positional data in a variety of conditions.
Application and Use Cases
SeaTrac is ideal for applications requiring reliable, approximate location tracking rather than precision accuracy. Its robust performance supports a range of underwater operations, including:
ROV/AUV Monitoring:
SeaTrac provides dependable location tracking for ROVs and AUVs during missions, ensuring operators can efficiently navigate and track their vehicles. By offering real-time positional data, it enhances mission planning and execution, particularly in complex underwater environments where high-precision tracking may not be necessary.
Marine Surveying:
Ideal for general surveying tasks, SeaTrac supports operations such as mapping underwater features, characterising seabed conditions, and monitoring marine ecosystems. Its approximate positioning capabilities make it an excellent choice for cost-effective surveys where relative location data suffices, such as baseline studies and habitat assessments.
Diver Tracking:
SeaTrac significantly enhances diver safety by providing real-time location tracking. This is especially critical during search-and-rescue missions, underwater inspections, or scientific dives. By offering reliable positional data, operators can monitor diver movements, maintain situational awareness, and respond swiftly to emergencies, improving operational safety and efficiency.