I would like to build a fish counter for installation in a glacial river with very turbid water, so the system must operate reliably in complete darkness.
My idea is to construct a tunnel through which the fish pass, with a sonar sensor installed above or to the side of the tunnel. A typical tunnel size could be approximately 60 × 60 × 150 cm.
The minimum requirements for the system are:
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Count all fish passing through the tunnel
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Determine whether each fish is swimming upstream or downstream
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Operate in muddy glacial water and total darkness
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Run автономously using solar power and batteries
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Transmit data via a 4G connection, since there is no mains electricity or wired internet available at the site
My question is whether the Ping1D sonar would be capable of handling this application. If not, what type of sonar or sensing technology would you recommend?
Hi @Fridgeir -
Welcome to the forums!
I’m a bit skeptical that using a Ping single-beam sonar in this situation would work, as the minimum range of 0.3m is for open environments, not an enclosed 0.6m diameter pipe. Quite a lot of multipath could result. Additionally, fish have very similar density to water, so you may only “see” the fish’s swim bladder.
As with most things, the best way to find out is to try it! “Tuning” the sonar’s parameters may result in success, but the default algorithm used was intended for bottom sensing. You could try modifying the open-source version of the firmware to better suit your application? Setting up a microcontroller to read the data stream and forward information over the internet should be possible, the Ping uses very little power.
The turbid water would likely prevent a laser-gate from working? I know those are often used in aquaculture. A camera with a light pointing at it form the opposite side of the tube could maybe see fish silhouettes?
Best of luck!