Small scale sonar for small scale war games between RC ships and subs

Hi BlueRobotics community,

My name is Justin and,

I have an interest in ROV’s(have yet to build or buy one just yet), and just recently, that got me thinking that it would be pretty cool to build a small scale RC submarine(preferably one that I can use in a pool, pond, or lake). In thinking about it further, I was thinking it would be pretty cool to have some war games with scale RC subs and boats(planning for them to be scale speed with FPV).

I was wondering, are there any small scale sonar systems that you know of that can pick up a small RC crafts. Since they’ll be operating not far from the surface and at a short distance, I plan to utilize standard radio equipment without a tether, so there’s no tether that should interfere with readings.

Thank you in advance,
-Justin(ins0mniac)

Hi there, there are sonars that could pick up items this size, but sonars are typically very expensive (starting around $5k) compared to other hobby gear.

Another problem is that you can’t penetrate water with rf to pilot a vehicle or get the sonar data back to the pilot. You will need a tether.

Has anyone adapted a fishfinder as a budget setup? The quality is pretty ridiculous these days.

There’s been a lot of talk on the subject over the years, but I haven’t seen anything done. The first problem is that there’s no api or publicly available protocol documentation on those things.

As a bare minimum, could you just run the data going to the LCD up to the surface? That seems like something you could do with a nano arduino and a twisted pair?

Actually, if you look at SVSeeker, you’ll find that he has incorporated a $1k-ish sidescan/ forwardscan sonar into his towed torpedo-like ROV. Sonar

Looking at fishfinders with side and down-scan sonar, this looks affordable.
Humminbird HELIX 7 Fishfinder 410950-1NAV, CHIRP MSI GPS G3