I would like to make a ROV with Tritech’s Gemini 720ik Sonar and a 1080p 20 fps IP camera. I’ve measured the IP camera consumes maximum 1.5 Mbps so it’s not that much of a deal. But in the datasheet of 720ik. It says that they reccomend 100 Mbps only for the Sonar. FathomX boards can supply 80 Mbps on a Twisted Pair line. I think that I will be losing data on Sonar. They have data compensation on their sonar. But the Sonar data is pretty important so I don’t want to use that specification. I think I will need a minimum of 150 Mbps data on the line. I cannot use fiber cable because of the cons of using it. Any of you guys have a suggestion to get a 150 Mbps or higher on a 300 meter twisted pair cable with minimum speed loss?
Hello Alkum. We have been running both the BlueROV2 at 1080/30fps video and a Gemini 720ik sonar on a single twisted pair using a custom dual Ethernet board (plus serial). This system is based on the FathomX and infact uses one topside to connect to the computer. We have customers with 200m systems working in the field and are testing to 300m. This is currently only available on our assembled STARS BlueROV packages, but we plan to sell the stand alone board imminently.
We find the 720ik has a 99%-100% quality link (excellent for any rov operations) and is well under 100Mbps durng operation. In reality, most Ethernet devices are well under this limit and a lot of hardware won’t actually handle 100Mbps continuous throughput. The data won’t be lost even if a packet is dropped, just resent. This process is transparent to the user.
If you have additional bandwidth requirements, there are only slight increases that can be gained on a twisted pair, in my experiance. Some ROVs use multiple high end VDSL modems on separate coax cables, but fiber may be a better option.
Hello Peter, what is your verdict on the Gemini products and integration with the BlueROV? We’re considering investing in a MB setup for turbid conditions. Are there other manufacturers you think we should consider also?