I’m looking for some opinions from those of you running more fully-equipped ROVs.
Our current build is running BlueOS on a Raspberry Pi 4 2GB, and I’m trying to decide whether the 2GB model is sufficient or if it’s worth moving up to the 8GB version.
Current hardware includes:
6 × T200 thrusters
Subsea Lights
Newton Gripper
4 × DWE cameras
Ping360 Imaging Sonar
Ping1D Altimeter
Cerulean OmniScan 450 Forward Looking Sonar
The vehicle will primarily be used for freshwater research, shipwreck exploration, and student education. We expect to have multiple camera streams active while simultaneously operating both sonar systems and recording data.
For those running similar configurations:
Have you found the 2GB Pi to be a limiting factor?
Does the additional RAM in the 8GB model noticeably improve BlueOS performance or stability?
Are there any CPU or USB bandwidth bottlenecks I should be thinking about with this sensor load?
If you were building this system today, would you choose the 8GB without hesitation, or is 2GB still perfectly adequate?
I’d appreciate hearing about real-world experiences before we order hardware. Thanks!
A 2GB Pi should work just fine in that workload! RAM typically ins’t a limiting factor…
Keep in mind that 4X exploreHD cameras won’t work if directly connected to the Pi - you will need to connect 2-3 of them to an external 5V source. It sounds like you’d be removing the standard internal low-light USB camera? You may also run into bandwidth issues, but you can always lower each cameras stream bitrate with the DWE OS extension.
With all 4 ports used, your ping360 can be configured to communicate via ethernet (which gives a slight speed advantage.) However, the standard 5 port switch would only have 1 port free - I’d recommend leaving it available for an upcoming camera upgrade!
A good topside laptop is most important for performance, especially with that many streams. I’d recommend a newer M series Mac!
I’d also point out that the Ping360 and Omnisan FS are a bit of a redundant combination? You may be better served by 2X Omniscan FS, as this gets you limited position hold and motion tracking functionality…The Ping altimeter is also redundant as I believe the Omniscan FS will provide an altitude measurement?
Thanks for taking the time to share your experience and recommendations, I really appreciate the feedback.
I’ll be bringing your comments back to my students so we can discuss them as a team. Part of this project is exposing them to different engineering perspectives and making design decisions based on real-world experience, so responses like yours are incredibly valuable.
A couple of notes from our setup and testing:
Our four DWE cameras are already powered from a dedicated external 5V supply, but I’ll suggest that they experiment with lowering the stream bitrates as you suggested.
We’ve noticed the overlap with the Ping1D as well. It was a unit we’ve had for some time and I’ll share your feedback as they look to keep or drop the it from the ROV.
I understand the thought that the Ping360 and OmniScan FS are somewhat redundant, we’ve found them to complement each other. We like using the Ping360 for continuous 360° situational awareness and navigation around the ROV, while the OmniScan is focused on the target we’re investigating—whether that’s a shipwreck, underwater structure, or other point of interest.
Thanks again for sharing your insights. It’s great getting feedback from people with hands-on experience, and I’m looking forward to discussing it with the students as we continue refining the system.