[HN Gopher] A New Wave of Underwater Comms Is Coming
___________________________________________________________________
A New Wave of Underwater Comms Is Coming
Author : Brajeshwar
Score : 33 points
Date : 2024-08-27 15:31 UTC (7 hours ago)
(HTM) web link (spectrum.ieee.org)
(TXT) w3m dump (spectrum.ieee.org)
| nradov wrote:
| Garmin scuba diving products now have underwater communication
| features built in. Unfortunately they're locked down so you can't
| use them for any other purposes.
|
| https://www.garmin.com/en-US/garmin-technology/dive-science/...
| slau wrote:
| For those who aren't scuba divers, 10m range is very
| impressive. Most radiowave-based systems have a range of 1-2m,
| with many being plagued with connectivity issues.
|
| One of the main use-cases is air integration, which allows you
| to have a transmitter connected to your cylinder which monitors
| gas pressure and relays it to the dive computer on your wrist.
|
| This is an alternative (or, depending on the school of thought,
| in addition) to having an SPG (submersible pressure gauge)
| which is hopefully attached to your left d-ring, but for many
| recreational divers stuffed in a pocket somewhere or scraping
| on the bottom.
|
| Air Integration is quite an investment (3-500EUR per
| transmitter) and there is basically no interoperability between
| brands.
|
| When Garmin came out with this, it made quite a splash, as all
| of a sudden instructors could keep an eye on the cylinder
| pressure of their students. This is a very minor use-case
| though, and I don't believe it's used a lot.
|
| As for underwater communication, a good chunk of the scuba
| community is quite opposed to relying on electronics for
| communication. Hand-based signals are quite good, underwater
| paper does exist, and if you're so far from your buddy that you
| need to wirelessly communicate you're in a lot of trouble.
|
| This all being said, as a boat captain responsible for the
| people underwater, I would love a local area network that
| allows me to pull the plug on a dive, or get some emergency
| notification. For example "weather is turning, please call the
| dive" or "I was blown off the wreck, please pick me up".
| nradov wrote:
| Garmin occasionally sends me customer surveys, and the
| questions on a recent survey implied that they were looking
| into boat to diver communications as a use case. I don't know
| whether they're actively working on this, but it seems like
| it could possible to add to future versions of their boat
| sonar products.
| jeewes wrote:
| > This all being said, as a boat captain responsible for the
| people underwater, I would love a local area network that
| allows me to pull the plug on a dive, or get some emergency
| notification. For example "weather is turning, please call
| the dive" or "I was blown off the wreck, please pick me up".
|
| In case you are interested, there is a Finnish company called
| UWIS (short for underwater information systems), that does
| exactly this [1]. Their system has buoyes that can track the
| diver units and provide communication channel between on the
| surface pc and the divers via wifi and sonar network. The
| system allows two way communication. Tight bandwidth of
| course as a limiting factor.
|
| [1] https://uwis.fi/en/
| itishappy wrote:
| For underwater communication, nothing beats the ol' hit-tank-
| with-knife (or the slightly more sophisticated tank banger).
|
| https://www.amazon.com/s?k=tank+banger
| yesfitz wrote:
| I didn't find anything about the potential effects on marine
| life. I'm not in the market for this, so maybe it's obvious to
| those who are, but it would be nice to address it somewhere for
| the uninitiated.
|
| But their modem[1] uses NATO's JANUS standard[2], which
| communicates at 11.5 kHz, which is just audible to humans, but
| well within range of marine mammals[3].
|
| 1: https://www.subseapulse.com/products/ 2:
| https://spectrum.ieee.org/nato-develops-first-standardized-a...
| 3:
| https://en.wikipedia.org/wiki/Hearing_range#/media/File:Anim...
| alas44 wrote:
| I completely agree, filling oceans/seas with noise seems like a
| good recipe to further stress marine ecosystems
| puzzydunlop wrote:
| For underwater acoustic systems there is a well understood and
| effective marine mammal mitigation process that's followed.
| Basically, slowly stepping up in power. Not sure if they're
| employing that here but if it involves NATO, I would expect
| that's being employed
| kayodelycaon wrote:
| This sounds like another startup that is ignoring all of the edge
| cases, testing, calibration, and certification that make this
| kind of product expensive.
|
| In this case it's a good idea. And they know exactly where their
| market is. I hope it takes off. :)
|
| There are plenty of applications where the reliability
| requirements are it works most of the time.
| moffkalast wrote:
| > Their transducer will convert energy into acoustic signals (and
| vice versa) using a modified device that's typically used to
| listen to marine mammals and costs about $400.
|
| That does beat the next cheapest option, the Waterlinked M16
| that's $2.4k for 1km range and 10 bits/s. They don't list any
| specifics about capabilities though.
| mikewarot wrote:
| It seems to me that if you need to generate large acoustic
| signals underwater, HASEL actuators might be the way to go.[1]
| Since they're effectively just bags full of incompressible fluid,
| they could work at any depth.
|
| Sensing sound.... that might be harder. Perhaps you could close-
| loop control the capacitance of the above, and "listen" to the
| error signal?
|
| [1] https://www.artimusrobotics.com/
| anfractuosity wrote:
| "The team is also working on a cheaper version of traditional
| transducers, which can cost more than $2,000 a piece" - Do these
| transducers require very high input power out of interest?
|
| Also what frequency does an acoustic modem typically use?
|
| And finally are they expensive because they're somewhat niche, or
| difficult to manufacture, both, or other reasons?
|
| Edit: looks like the datasheet for 'Waterlinked M16', mentioned
| in another comment answers the first couple of questions. Seems a
| lot lower in power than I'd have thought.
| mncharity wrote:
| Years ago an oceanography-oriented founder told of attempting to
| patent their nice transducer. The response was unexpected: the
| prior art is classified, so no patent, and stop all use.
___________________________________________________________________
(page generated 2024-08-27 23:00 UTC)