Air Integrated Computers "Could Potentially Kill You."

[Angelo Farina]

No computer can factor such things and some of these have nothing to do with deco and nitrogen absorption . Hence deco calculations can't be altered based on these.
All the best

But Scubapro-Uwatec claim of doing exactly this. And, in my understanding, these capabilities are the only serious reasons for going with an AI computer, as on all other sides I see only more risks and disadvantages...
Read here:
https://www.scubapro.com/sites/scubapro_site/files/trimix_user_manual-eng.pdf
And see chapter 1.1 and the related figures. These computers are claimed to evaluate the workload (based on air consumption or hearth rate) and to adjust the saturation profile accordingly...

See also the manual for the Galileo computer:
https://www.scubapro.com/sites/scubapro_site/files/galileo_sol_eng.pdf
At pag. 34 you see this picture and you read the following explanation:

The sensitivity of the workload calculation to changes in breathing pattern can be adjusted in 25 steps: this has an effect on how the algorithm accounts for changes in breathing pattern in the decompression calculation (it has no effect if the WORKLOAD setting in section 2.9.5 is set to HEART or OFF).

 

[drakcheslav]

I've been using these two, as my primary and backup and with an SPG.

I know that mos of the people think that cressi is conservative, but I've constantly found I have more NDL than a lot of others in the group if I'm group diving, and when diving home, max we go is 11m, so no worries for deco, and we usually dive until we're out of air.

These two work perfect. Citizen is a great bottom timer/spg, and I can clearly see what ever is written on the Leonardo's screen. Only think I'm missing from the dive computer is average depth and start and end time. Which I get from my watch.

 

[kelemvor]

I wonder what the responses would have been like a couple years ago pre Perdix AI.

You don't have to wonder. The topic has been repeatedly beat to death on scubaboard. Just go read old threads. Most tech divers eschewed the use of AI prior to shearwater adding it. Most going so far as to say a computer was crap for even having the feature as an option. Even right up to the day before SW announced the feature. Then, all of a sudden, it was no big deal.

I sold my shearwaters two years ago and bought Ratio iX3M's instead.

 

[The Chairman]

Hence it cannot know when/if SAC is higher than "normal" to compensate anything based on that decision.

Rly? I find making such causal connections.pretty intuitive. I'm not sure I understand what you're saying here.

 

[ToneNQ]

............these capabilities are the only serious reasons for going with an AI computer, as on all other sides I see only more risks and disadvantages..................

You can argue AI adds disadvantage in that you call the dive if you lost air pressure monitoring. This is an existing control for all diving equipment failures, even those where we carry redundancy. I've had a few dives called over the years, none due to AI. The only AI issues I've observed occurred before getting into the water, and were resolved. Perhaps the complexity is another disadvantage for some, but its not for others.

Regarding risk, AI transmitters do not add any additional failure modes that put the diver's life at risk. There is one additional functional failure mode, which is the loss of signal. That is easily controlled by ending the dive. AI does nothing else, it does not detract from a single other thing from your 1975 training methods. Your ability to add time and use tables is not impeded by AI. The argument that AI adds minimal benefit for its cost is solid, the argument that AI adds risk is not supported by evidence that I have seen.

As for the advantages I can see everything in one glance; gas levels, consumption, depth, time, NDL/deco time, @+5, etc. There are no additional instruments to check, nothing to unclip and re-clip every 15mins, there are less o-rings, less hoses, one less clip on my left side d-ring etc. The only out-of-air situation I've had in my diving career is a OW diver with an SPG that he wasn't checking. The instrument, manual or otherwise, is an administrative control requiring procedures. Make the procedure simple and the control is more effective by being repeatable. There a better ways than the old military doctrine of training repetition, AI is one of those.

 

[boulderjohn]

A few comments on things being said in this thread.

1. The rate at which you breathe air has no effect on nitrogen levels in the tissues.
2. Perfusion (flow of blood through the tissues) does have an effect on nitrogen levels in the tissues. A diver working harder than usual will absorb more nitrogen than usual because of this. The rate at which you breathe may provide a clue as to the rate at which you are working and the resulting blood flow, but it may also be unrelated.
3. Some ScubaPro computers use heart rate monitors to measure the diver's effort level and make adjustments accordingly. I was asked to test an early model a number of years ago.
4. I do not know how those computers use heart rate data to make calculations. My normal resting heart rate is about 40 BPM, and if I am riding an exercise bike for an extended period of time, that rate will go into the 70s. Many people start in the 70s and will be in the 110 range with that same amount of exertion. I assume ScubaPro has figured that out, but I don't know how.
5. I am not aware of any research validating the adjustments being made by those computers.
6. I am not aware of any computer using breathing rate to adjust its nitrogen loading calculations.
7. I do not do computer sales and may be unaware of recent changes in some models.

 

[Bob DBF]

Air Integrated Computers "Could Potentially Kill You."

I guess, in the same manner as not paying attention to what you are doing at any time can potentially kill you, say walking across the street while texting your bff.

Ones life support equipment is located between ones ears, not any particular piece of hardware they carry.

 

[Jcp2]

I would like air integration as a convenience because then I could look at my wrist and have all the data there that I need, instead of checking my wrist and then checking my SPG. I do the two together out of habit because I want to know how deep I am, how much air I have, and how much time I have. Being a vacation leisure diver, I generally know the maximum time I have and the maximum depth of the dive, but the dive profile is dependent on what I am interested in, what my partner is doing, and how we both feel. It's definitely not square.
I think I would know if the air integration is off, based on my experience without it, as well as experience with other computerized sensor devices. For instance, I like the GPS on my car for directions to a new address in a familiar city, but am willing to ignore it if I understand that it is giving me imperfect directions. I do really depend on it when driving somewhere completely new to me, but I generally consult a map to have some idea of the geography so I have some independent frame of reference.
Similarly, I have a nice fitness watch that tracks my heart rate, running pace, and recharge status, but I also have a general idea of what my working thresholds are for various degrees of effort. That way, I know that there must be a satellite signal problem when it states that my pace is suddenly 6 miles a minute when my breathing and my eyes tell me that I am really at an 11 minute pace, or that I'm not having a heart attack or atrial fibrillation when the heart rate jumps to 180 when everything else is the same, or that I really am tired even though the watch says my fitness battery is topped off.

 

[Degenerate]

I have my transmitter on a short hose, which I bend down and tie with a bungee loop to a regulator hose. So the transmitter is always tucked between the tank and the wing. In that position, it's practically impossible for the AI transmitter to be bumped. The tank valve or my head will protect it

If (and that is a very big IF) I would ever get a transmitter, it would be on a port pointing downwards, on a first stage that is angled (as they typically are on a DIR setup).
There is absolutely no way that transmitter would be at risk of catching onto anything that my valves or first stages wouldn't have caught on to ages before that.
I would never put it on a hose as that would just be an extra failure point to me, but to each their own.

 

[Angelo Farina]

6. I am not aware of any computer using breathing rate to adjust its nitrogen loading calculations.

I posted above the manuals of two Scubapro-Uwatec computers which describe they are doing exactly such an adjustment...
I do not own them, so I cannot testify if, after a strong workload causing anomalous gas consumption, the deco time is affected significantly or not...
But if they do what they claim, (and I do not see any reason for which Scubapro should lie) I see this feature as a very good point in favour of AI computers. Something which is possibly worth the additional cost, the added complexity caused by the need of using the second HP port of the regulator for the transmitter, the inconvenience of changing the battery of the transmitter, etc...
Without this substantial benefit, I really do not see the point of having to watch the computer during the dive just for seeing the air pressure. The SPG is there at hand, and is much more readable. I usually watch the computer only when I am back at 9m, and it is time to evaluate if some deco is required, and in case how long...