Hydroacoustic transduction - Page 1
Forum section: electronics / projects

author: Neuromodulator
author_rank: Regular Contributor
timestamp: February 26, 2018, 02:49:03 am
content: Hello,I'm trying to design an hydroacoustic modem, so far I've played mostly at algorithm level, to perform the modulation and demodulation. Even though I can do some fun tests using the computer speakers and microphone, I would like to perform some hydroacoustic tests. My plan is to design a very unexpensive system (hopefully <100 USD) that can communicate at >100 m (below 100 m I would do better with an optical link). It appears that the right way to go is to design a tonpilz transducer with comsol or some other multiphysics tool, but as I would like to avoid at this moment to dive into mechanics, hydroacoustics and modelling, I was wondering if there is a simple transducer solution (something I can play with). I thought maybe an ultrasound cleaner transducer could work as its design appears to be similar of a tonpilz. Have anyone tried to use one for acoustic communication? Any tips on how to perform the transduction (maybe there are better approaches)?thanks

author: Marco
author_rank: Super Contributor
timestamp: February 26, 2018, 06:28:35 am
content: I think both horn and bare disc cleaning transducers are too high Q. I think cheap fish finders (which also need decent bandwidth) do use bare piezo discs, simply backed by air, but I think they use thickness mode resonance where the bandwidth is higher. Thediscslooks far thicker thanthe ones used for cleaners. You can get afish finder from Chinafor under 35$, so you could just tear one down and see.UCE Ultrasonicshas some of their fishfinder thickness mode discs available onaliexpress, but only in large quantities. If thickness mode resonating discs without complicated tensioned mass/horns do work though you can probably find other suppliers too.

author: GerryHarvey
author_rank: Newbie
timestamp: February 27, 2018, 12:10:50 am
content: Hi there**full disclosure - I work for PZFlex**I think we can help you with the simulation aspect here. We will be releasing an affordable, on-demand simulation platform in the coming months, to allow users to dip in and out of this type of multiphysics work without the need for a very large up-front investment.If you're interested in more info - pm me and I'll get in touch directly.Sorry if this comes across as a salesy - just want to help out if we can.ThanksGerry

author: Lightages
author_rank: Unknown
timestamp: February 27, 2018, 01:08:59 am
content: Dave needs to jump in here. He worked for a company that made this kind of equipment.

author: Neuromodulator
author_rank: Regular Contributor
timestamp: February 27, 2018, 10:24:27 pm
content: Thanks for the replays and links. I was wondering how well it would work to just stack piezos compared to just use a single wide piezo. Also, how easy/hard is to just dampen the piezo to reduce the Q? Thanks for the offer Gerry, but I'm just a student (in a third world country) with a tight budget that can barely afford hardware, so paying for software is completely out of my reach, eventually I can get access to comsol in the university if they have any license, I'll have to ask.