Subsea Positioning
Omnitrack USBL
Omnitrack is Cerulean’s flagship subsea positioning system — a ring buoy carrying the ROV Locator together with dual GNSS receivers, so the topside knows both where it is and which way it is pointing. Heading comes from the two GNSS units rather than a magnetometer, which takes magnetic interference out of the problem. It is a family of configurations, not one piece of hardware.
At a glance
- Maximum range
- 300 m
- Update rate
- 1 Hz
- Max depth exposure
- 300 m
- Buoy weight
- 8.6 kg tethered · 7.7 kg Wi-Fi
- Topside link
- 25 m PoE tether or 2.4 GHz Wi-Fi
Full specification — 16 published figures ↓
Every Omnitrack USBL Configuration
The same USBL positioning system. What changes is how the topside connects to it, and what comes in the box.
The same USBL positioning system. What changes is how the topside connects to it, and what comes in the box.
Omnitrack USBL, and what it produces
Cerulean’s own photographs of the hardware, and real output from it — not renders.
Every published figure
16 specifications, as Cerulean publish them. Nothing here is estimated or converted.
| Maximum range | 300 m |
| Update rate | 1 Hz |
| Maximum depth exposure (minimum crush depth) | 300 m |
| Buoy weight, tethered version | 8.6 kg / 19 lb |
| Buoy weight, Wi-Fi version | 7.7 kg / 17 lb |
| Topside link | 25 m PoE tether, or the Wi-Fi module |
| Wi-Fi band | 2.4 GHz |
| Wi-Fi antenna supplied | 7 dBi |
| Wi-Fi range, to a similarly equipped base station | about 250 m |
| Wi-Fi range, to a bare laptop | 20–30 m |
| Wi-Fi module power draw | about 6 W (400 mA at 14.8 V) |
| Battery endurance | about 10 h on a 4,000 mAh 14.8 V pack |
| GNSS position error | 3–5 m CEP |
| GNSS compass (heading) error | 0.5° probable |
| Angular resolution, topside to subsea | 2° typical |
| Combined angular error | 2.1° probable |
Range, update rate and depth exposure are the three figures Cerulean publish on the Omnitrack product page. The rest are from the Omnitrack reference documentation.
System accuracy is not a single number. Cerulean give CEP as square_root( 25 + ( sine(2.1°) × slant range in metres )² ) — so the closer the ROV is to the buoy the better it gets, with the floor set by GNSS position accuracy.
The buoy is supplied with either the 25 m tether or the Wi-Fi module, never both.
Published by Cerulean — specification page
In the box, and what it does not include
A sonar is not a system. These are the parts you will need alongside it — each one with Cerulean’s own source.
What’s in the box
- Ring-buoy float with its frame and brace
- Sting in upper and lower segments — hinged on current units — with the retention bolt and thumbscrew
- ROV Locator transceiver with its grip and hose clamp
- Two folding GNSS antenna arms, assembly bolts and an antenna stowage clip
- Battery / Wi-Fi enclosure with its mounting hose clamps, and the battery
- Either a 25 m PoE tether or the Wi-Fi module with its 7 dBi antenna — one or the other, never both. The Network Hub is included in the wired PoE bundle.
What else you need
- Nothing else — the bundle is the systemEach Omnitrack configuration ships with the Network Hub, and the wired one includes the 25 m PoE tether. Source →
- A Blue Robotics vehicle, for the easy pathOmnitrack is built to drop onto Blue Robotics systems and hand the autopilot geolocation and odometry, which is what enables waypoint navigation and position hold. Source →
We supply the brackets, hubs, cables and spares alongside the unit — see what fits Omnitrack USBL → or add them to the same enquiry.
Common questions
Answers Cerulean publish, each linked back to the page it came from.
What is Omnitrack, exactly?
A family, not a single box. It is a set of hardware configured to suit different positioning needs — the tethered buoy and the Wi-Fi buoy are the two minimum recommended configurations. Source
What does it give the ROV?
Geolocation and odometry handed straight to the autopilot, which is what makes waypoint navigation and position hold possible. It is built to drop onto Blue Robotics systems. Source
How is it better than a bare ROV Locator?
Cerulean say it directly: the ROVL is low-cost, medium-accuracy localisation, and better performance comes from using it as part of an Omnitrack system. Source
Omnitrack USBL on video
Published by Cerulean Sonar on their own channel.
Request an Omnitrack USBL quote
Tell us the vehicle and the water depth and we will confirm the exact part number — and say so if a different model suits the job better.
Anything you have added to your quote list is carried into this form automatically.