Will Air Integration in dive computers replace the SPG?

[Bob DBF]

It's a known fact new technology almost always replaces old technology, especially analog technology. Just about every piece of technology in our homes, cars, businesses have been replaced by electronic technology. As far as scuba goes, dive computers have basically replaced physical tables and depth gauges. I believe the SPG itself replaced the J valve.

From my understanding, since my memory is fuzzy, the J valves and SPG were available at the same time, but the SPG cost more than a reg set so the J valve was the go to solution in the '60's. A pressure gauge was used on the surface to determine the tank pressure for the start of dive. The SPG won the longevity contest because the price dropped and the J valve could fail in a number of interesting ways which may or may not be caused by the operator, as well as having its set point drift.

In order for a new technology to replace an old technology, it needs to be cheaper, more reliable, and safer. I could see AI getting way more popular with the recreational NDL crowd, if for no other reason than people are electronic gadget junkies. I think it would take a lot longer, if ever, to catch on as the only tank pressure indication with those doing serious deco and/or overhead.

I bought an SPG as soon as I could afford one sometime in the '70's, I finally broke down and bought a computer in 2005, so my chances of getting AI before I end my diving is more dependent upon the lottery numbers than anything else. And should I get AI, there is no way I would give up the SPG. I dove when you had to guess what was left in your tank and I didn't like it then, on AI only I am one errant electron from being in the same spot again.

I'll start by adding one of the arguments I heard against AI. Many experienced divers say AI is unnecessary because they have a good idea of exactly how much gas they have in their tank. Then my argument is if that truly is the case, then why do you have a dedicated device with a higher risk of air loss failure when you could simply just "integrate" that data into your computer and remove the failure points of a blown hose, a blown connection at the hose and SPG and the possibility of the face plate blowing out?

You ignore the thousands of bits of continuing data that keep the transmitter and receiver in sync, any one of them behaving badly could break the connection, yet you count them all as one failure point.

As for face plates blowing out, decades ago that was solved by putting a blowout plug on all SPG's, limiting the oraface size on the HP hose and reg HP port reduced flow to the SPG, as well as reducing other hazards of HP hose failure. Last face plate I had whizz by me was in the '70's sometime. You might find a vintage piece without the blowout, but it wouldn't read over 3000# on the gauge.



Bob
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"the future is uncertain and the end is always near"
Jim Morrison

 

[DiveNav]

..... So will Air Integration replace the SPG? ....

Yes .... eventually.

 

[chrisch]

... I could see AI getting way more popular with the recreational NDL crowd, if for no other reason than people are electronic gadget junkies....

Top post. Spot on.

 

[DiveNav]

.... I'm not familiar with the technology behind transmitters but it would have to be universal so any computer could connect to any transmitter in order to make the SPG "vintage" gear. ......

Most AI systems use low frequency EM waves (from ~6KHz to ~40KHz - depending on the manufacturer) with some basic coding. One manufacturer uses sound waves.
All the systems are incompatible either because they use different technology (sound waves vs EM waves), frequency or coding.

 

[CuzzA]

You ignore the thousands of bits of continuing data that keep the transmitter and receiver in sync, any one of them behaving badly could break the connection, yet you count them all as one failure point.

True. I was speaking specifically to gas loss by a physical failure though. Reliability of the transmitter is paramount. But, we've heard stories of stuck needles on SPG's too, so they are not exactly 100% reliable. How often does that happen? I don't know, probably not very often.

---------- Post added January 12th, 2016 at 12:03 PM ----------

Most AI systems use low frequency EM waves (from ~6KHz to ~40KHz - depending on the manufacturer) with some basic coding. One manufacturer uses sound waves.
All the systems are incompatible either because they use different technology (sound waves vs EM waves), frequency or coding.

Yes. Thank you for the explanation. So the scuba industry manufacturers would have to come together and mutually agree on one technology. How likely is that to happen?

 

[agilis]

Some battery powered wireless transmission replacing an uncomplicated virtually trouble free inexpensive direct connection? Don't be ridiculous.

Experienced divers check their SPGs at least as often as they glance at their computers.

 

[Wookie]

Yes. Thank you for the explanation. So the scuba industry manufacturers would have to come together and mutually agree on one technology. How likely is that to happen?

All of the regulator Manufacturers got together to standardize the LP hose. Except Aqua-lung. It took 65 years. For a hose. Manufacturers can't agree on computer algorithms, batteries, screen size, features, or color.

I think standard transmitters is asking a lot.

 

[highdesert]

I would never dive without my AI computer (hose and console, not wireless) AND my wrist computer and SPG. Full redundancy, every dive.

 

[CuzzA]

Some battery powered wireless transmission replacing an uncomplicated virtually trouble free inexpensive direct connection? Don't be ridiculous.

Are you sure?

This `telephone' has too many shortcomings to be seriously considered as a practical form of communication. The device is inherently of no value to us.
- Western Union internal memo, 1878

What use could this company make of an electrical toy?
- Western Union president William Orton, responding to an offer from Alexander Graham Bell to sell his telephone company to Western Union for $100,000.

Hey, don't call me ridiculous. I didn't create AI, nor have I forced just about every dive computer manufacturer to offer it.

 

[Lorenzoid]

I don't know about reliability, except in an anecdotal way, but I agree about the "feel" issue. We are analog creatures, and use digital only when necessary. How many people have digital watches? Or digital speedometers in their car? The human body and mind seems to be most comfortable with analogs. Or perhaps I'm just an old fart.

Well, to play devil's advocate against my own post, one could argue that a mechanical "needle" could be digitally simulated to appease our analog brains. Or a bar graph, etc.

Where's the sense in checking less often? Do you want OOA to be a surprise? Don't you watch your depth gauge and timer? Wouldn't it be convenient if you knew your remaining gas concurrently at knowing your depth and run time?

I do watch my depth and time, and so checking gas less often lets me concentrate that much more on depth and time and, more generally, all of the other tasks the dive entails. The school of thought that's been instilled in me is that if you have a good grip on your air consumption rate, you don't need to check your gauge so often, because you can predict with good enough accuracy what it is going to read. We should aim for predictability, but if the dive must involve some unpredictable factor--say, you're doing some kind of unfamiliar task--then the solution is to bring enough of a reserve of air to account for the unpredictability. There should be no need to check air obsessively. If every 15 minutes during the dive I spend six or seven seconds unclipping my SPG, looking at it, and clipping it off again, that is no inconvenience to me whatsoever.

In the other thread, it was mentioned that some people do specialized diving, such as handling a two-handed camera rig, or hunting or scootering, or some other kind of intensive (and perhaps unpredictable) work, in which AI may address a problem such divers have. I suppose I can see that. For the rest of us, once we have a handle on our air consumption I just don't see any major increase in convenience.