iDeco - iPhone OC & CCR Decompression Planning

[ppo2_diver]

Any chance of getting it for OS X laptops?

 

[flareless]

Just wanted to thank you again Brock for this awesome piece of software. We've been using it for dive planning and it works great. This past weekend alone I had two divers telling me they were going to get iPhones just so they could have iDeco!

<EDIT> OSX would definitely be nice!

 

[CuriousRambler]

I downloaded it on my friend's iPhone, who doesn't even dive, just to play with it. I want it for the google phone! I'll be grabbing one next month when my "I've had this crappy T-Mobile plan way too long so I get a cheap phone now." discount kicks in, can't wait to see it for android.

I'd also love to see it for OSX!

 

[Van Isle]

Brockbr:
this is an amazing app, and super-amazing given the price point!

I'm looking for a donate button on iphonedeco.com and can't seem to find it...would donations lead to some sort of assumption of liability?

A few other thoughts:
-a port to OSX would be rad! With transfer capabilities, i.e. build and save on either unit.
-a function as a No-Deco dive planner so that one could plan no-deco dives on EAN (and air). Obviously this app will do that for those who understand deco diving, but not so much for rec-divers just looking to supplement the planning on their diving computers for EAN. Or am I mistaken? (I am not a 'tec' diver)

Many thanks,
Mitch

 

[Blackwood]

Just use your judgment. If you input a series of profiles which start returning many minutes of stops, you are outside the "no-deco" realm and need to pull back the profiles.

But if you go put in something like 40 minutes at 30 feet, it's not going to tell you to do any stops.

 

[Van Isle]

While using my limited judgment is often a good idea, it definitely puts me outside my training level in this case! It is possible to plan a no-deco dive on iDeco (say, 100ft/10mins bottom time/EAN 36) where iDeco "requires" multiple timed stops. At some point the deco stops change from "encouraged" to "mandatory" vis-a-vis training agency requirements such as PADIs. There is no prudent way for a non-technical diver using this to plan rec EAN dives to know if he is "deco" diving or "no-deco" diving. Or is there? If that is far beyond the purview of this app, so be it. But it'd be sweet and way more comprehensive than the other apps in the app store.

Many thanks,
Mitch

 

[Blackwood]

disclaimer: Many of us don't think of decompression as a black and white thing... deco or no-deco. For example, I don't view the "no stop" tables as "no deco." Rather, I view them as maximum time at a given depth for a decompression time governed by a constant ascent at a maximum rate. And I think that to use a software which spits out a specific profile, you have to adopt that mentality. So take what I'm saying with a grain of salt.

If your standard dive table reads a maximum ascent rate of 30fpm and asks for a 3 minute 'safety stop' at 30 feet, what it's really saying about a dive to 100 feet is:

100feet-70feet / 30fpm = one minute
70feet-40feet / 30fpm = one minute
40feet-30feet / 30fpm = twenty seconds
Safety stop = three minutes
30-0 = one minute

In other words, for a dive to 100 feet within table limits, don't get out of the water in less than 6m20s. If the 'Safety Stop' isn't required, it's saying to not get out of the water in less than 3m20s.

So I guess if you want to use iDeco my suggestion would be to limit your dives to those that require a total ascent time which is less than Maximum Depth/Maximum Ascent Rate + 'Safety Stops', where the ascent rate and stops jive with the tables you were trained with.



My suspicion is that adding an algorithm to spit out "no deco" would involve quite a bit of additional programming. It would have to run through the math to give its theoretical ideal profile AND run through the math with a constant ascent rate and then decide whether the pressure gradients on the constant ascent profile are acceptable and give a response accordingly.

Perhaps Brock has a better suggestion, as he understands his code.

 

[Van Isle]

Understood. I appreciate the response. Unfortunately, the prevailing mentality under which most of us beginners are trained builds a huge gulf between no-stop, "rec" diving and "technical" diving when of course in reality there is a gray area. All dives are decompression dives of a sort...

I think Agencies need to better address these real world concerns and offer "grey area" training. I don't need (yet?) full on tec training, but I think some basic decompression training, the theory at least, would make one better understand what is happening at depth.

And apologies to our iDeco coder/diver who has written this invaluable program! Sorry for the thread hijack.

Mitch

 

[flareless]

There IS a gulf between Tec and Rec divers and there should be. Rec divers don't have to concern themselves with the additional info/detail/gear/etc required for Technical Diving. As well they shouldn't. A very small percentage move from Rec to Tec. For those who do, some find the rewards great and others wash out of the training.

It was kind of funny 2 weeks ago, driving to a place for dinner with 2 guys on a dive trip. One guy was my Tec team-mate and the other was a PADI DM. The two of us were going on about the details of our upcoming dive, deco, schedule, etc.. and the DM sort of sat there with a look like "where the hell did these guys learn so much of this extra stuff".

The point is the two dive styles are different. As for iDeco; leave it alone. As the name states, it's for decompression diving. A nice RDP will do the job perfectly for no-stop diving. Maybe someone can write an RDP for the iPhone. Just don't gunk up my beautiful iDeco with a bunch of useless (to Tec Divers) no-stop nonsense.

Just my opinion, thanks for listening!

 

[brockbr]

Brockbr:
this is an amazing app, and super-amazing given the price point!

I'm looking for a donate button on iphonedeco.com and can't seem to find it...would donations lead to some sort of assumption of liability?

A few other thoughts:
-a port to OSX would be rad! With transfer capabilities, i.e. build and save on either unit.
-a function as a No-Deco dive planner so that one could plan no-deco dives on EAN (and air). Obviously this app will do that for those who understand deco diving, but not so much for rec-divers just looking to supplement the planning on their diving computers for EAN. Or am I mistaken? (I am not a 'tec' diver)

Many thanks,
Mitch

Mitch -
Sorry for the delayed response. An OSX port would be straight forward, but really, the beauty of iDeco is the mobile interface. I am also the author of MyDecoPlan.com, which will run on Windows, Linux and OSX. It is NOT finished yet (read: DO NOT dive on it).

As for a recreational planner for the iPhone, I am tossing this idea around right now. As stated by others who responded to your posts, it isn't as straightforward as just running the Buhlmann model until it starts to incur "required" stops.

The problem relates to tables vs safety stops vs "required" safety stops (yes, there is a set of tables with that in them). For example, if you dive using the Navy tables, and you push them to the brink (eg. you dive to the absolute NDL), you will eventually get bent. The Navy wouldn't apologize either, since everyone should know the Navy air tables are the "limit" for a fit person, with a small percentage of those fit people getting bent.

So, this leaves us with needing to "pad" the numbers. How do we do that? PADI, SDI, NAUI, IANTD etc all have their own way. With the PADI RDP, they have a set of numbers - These are different from the Navy tables. With IANTD, they are different yet again.

The question becomes "who is right?" or, better yet, which is "more" correct.

The problem is that anyone wanting to use an application like this will presume it follows "their" agency's numbers, because after all, that's the only agency that exists

For me, that means either:
a) Support all of the agency's tables
b) Create yet another derivative based solely on the Buhlmann algorithm using Gradient Factors.

(a) This has problems because the app has to support not only different sets of numbers, but sometimes different methods for calculating repeat dives (pressure groups are different, etc). The user would have to select the "right" set of tables, and the app would have to understand how to put it all together.

(b) Has problems because it would drastically shorten NDL since a true Buhlmann/GF will incur a *real* stop in a shorter amount of time and at a deeper depth than a safety stop. <- Recreational divers should read that statement and cringe. Yes - That's right, a properly executed recreational dive, when pushed to "NDL", will sometimes result in a required stop based on the Buhlmann/GF algorithm.

Another problem is that unless is uses the PADI numbers, I'd have to suffer through all of the "this thing is broke" email's from well meaning beginner divers. Not something I have a lot of time for.

I am open to ideas and suggestions though.

b.