I'm looking into building a small electronic sound beacon that can be dropped to the bottom of a pool to give audio cues to swimmers.
Simple tones or beeps that are loud enough for a swimmer to hear from a few feet away are what I'm looking to create with the device.
Does anyone have experience with this?
I have access to a 3D printer, but trying to figure out how I can design an enclosure that would keep the beacon's internal electronics (microprocessor, speaker, etc.) dry, as well as allow sound from the speaker to escape out into the water to be heard.
Are there any 3D printing filaments that would be best suited for this?
A major problem with creating sound under water is that speakers or transducers intended for air do not work effectively in water.
They are extremely inefficient in coupling electrical energy into sound energy, simply because air and water have acoustic properties that differ by orders of magnitude.
People may have developed underwater speakers that have acceptable efficiency and audio reproduction in the human hearing range. If so, your favorite search engine will find them.
Simple audio beeps that go off at regular intervals so that swimmers can use the sound to get a rough position of where they are in a swimming lane based on knowing where the beacon is placed and the change in loudness as they approach it.
Ones coming up in a Google search are larger than what I'm imagining. I'm looking for one a few inches max in diameter to keep the size of the device as compact as possible.
The OP wrote of swimming in lanes. So, if you see swimmers in lanes, they have their eyes open with sometimes goggles on their eyes. But! if the swimmer has their head fully or partially out of the water, they are not hearing the sound in the water. Perhaps the OP can give a better description of exactly what is happening.
For a long time My wife did not want to open her eyes when swimming at the swimming pool (get red eyes from chlore or salt or infections), could not wear her glasses, and could not see anything with googles, so did not bother having them. She would try to stay the course and occasionally hit the line or another swimmer
Not sure a sound signal could have helped, but could be a fun idea to explore
Nowadays googles adapted to your eyesight is no longer super expensive and so she got that and all is good when we go swimming
Good question. This device would be for visually impaired swimmers. Although I have also thought about including a strobe light for users who would still have some ability to see.
Adding a strobe also begs similar questions to the speaker - how could I create a waterproof enclosure to house the electronic components that control it, and how can I make the light waterproof or otherwise expose it to be seen without getting ruined by the water?
You never need a waterproof enclosure for the electronic part. ONLY for the speaker and the light. Don't forget about powering your devices. If battery, consider the size. If mains powered, consider the safety considerations and tests your device must pass.
Have you gotten written clearance from the pool owner for your devices?
