Ping 360 stand-alone on long tether - how to?

Blue Robotics Products Ping Sonar Devices
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Hi all,

First off, I am sure there must be some information out there on this topic, but I didn’t find any relevant discussion. I am rather naive to electronics and may simply lack the right key words. So, my apologies if I repeat already solved challenges.

I would like to use a Ping 360 on a long tether (up to 50 m length) with a topside PC and power connected. This, I need some help with.

A bit of background first:
I have used the Ping 360 connectd to a Latte Panda V1 mini-Pc running windows. For that I have connected a BlueRobotics lithium-ion battery to the Ping360. The mini PC was powered from a separate powerbank and the ping 360 was connected to the mini-PC via usb. All components were connected inside a 4" acrylic tube and the ping360 was mounted just on the outside. All cables were kept as supplied from BlueRobotics. This systems worked very well, but our needs are such that we want to record continuously and directly analyze data on-site.

Our challenge:
We aim to use the ping 360 at depths between 5 m and 40 m depth, and we need a tether to a PC that is mounted topside. Since we want to record continuously, we also need to supply power from the surface.
I have build a camera setup many years back, were I used active usb-to-lan converters to bridge several 10 m with usb connections to the camera under water and PC at the surface. I guess I could do the same here, but I also wonder if I can simplify that setup somehow.
My question is if anyone has a suggestion for a lean and elegant setup for a tethered “stand-alone” solution (that is, without going via the BlueRov2)? Can I, for example, connect the ping 360 to a fathom-X tether interface board, run a 4-wired tether to another fathom-X interface board topside and connect a PC to that board via usb? In that case, do I need to go with a Fathom-X Tether Interface in between the topside Fathom-X tether interface board and the PC to supply sufficient power?

Any knowledge and suggestions are welcome and highly appreciated. Please keep in mind that I have very limited background :wink:

Cheers,
Lars

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Hi @LarsG,

I asked about this internally and was told someone has previously made a direct ethernet connection to a Ping360 using 30m of our Fathom ROV Tether, with the spare two twisted pairs used for the power and ground connections.

Some noteworthy considerations:

  • You’ll need to consider voltage drop through the cable
    • Using a higher voltage is preferable where possible to reduce the current draw requirements, which reduces the losses
  • Our tether is not rated to a specific communication bandwidth for ethernet, and it’s possible the capacity will be insufficient at the length you want
    • If this is the case you could potentially use the Ping360 in the RS-485 configuration and connect it to your topside computer through a BLUART
      • This is also useful if you specifically want a USB-based connection and not an ethernet one
    • Fathom-X boards could also solve this, but are likely overkill for the situation
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Hi @EliotBR,

thank you very much fo rthe quick and comprehensive answer! This is good news for us, indeed. I will try with an ethernet connection and will report back once I have tried.

Thanks again, this was very helpfull - and thanks also for the links. Those are highly appreciated :slight_smile:

Cheers,
Lars

1 Like
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Note that the Ping360 is wired for USB connection by default, so to use ethernet or RS-485 you’ll need to change the communications interface :slight_smile:

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A short update. After finding some time to get back to this, I tried an ethernet connection. I wired the Ping 360 via ethernet cable according to the description here:

Pingviewer on my Windows machine found the Ping360, but I could not start the Ping360, as Pingviewer prompted that the connectino needs to be configured. I have checked the IP address of the PC and configured the Ping360 so its IP address had the same numbers as the PC, except for the last number. Unfortunately, I did not have success, as Pingviewer continued to tell me that I need to configure the connection.

Instead of trying any more, I swapped to RS485 connection on the ping360, using the Bluart adapter (BLUART USB to TTL Serial and RS485 Adapter). I used a battery for power supply on a short cable for a quick test, and the Blue Robotics tether with 4 twisted wires. I plan to use two of these for power later on. I have tested this setup with 100m tether, and everything worked fine.

For those interested to replicate this, I will post another update when I have made the connections also to the power topside, and will post a picture on the setup. :slightly_smiling_face: