We started our foray into dive computer design back in the 90’s with the idea to put a Palm Pilot into a case, with appropriate sensors connected. It quickly became apparent that by the time you created the sensor interface and the processing necessary to deliver the data to the device, you would be better off, and far more efficient, just building a dedicated graphic dive computer from the ground up. So that’s what we did.
This phone-in-a-case discussion comes up frequently, and clearly lots of folks have had the idea to house a phone with some software and sensors and turn it into a dive computer. I suspect some of the crop of dive computers we see appearing are in fact based on Chinese pre-made modules that are basically designed to be phones, running some kind of OS that allows for app development.
A couple of points:
The OS underlying phones is not necessarily designed to be a real-time system. And there is a lot of overhead in a phone, which costs battery time. Reliability in a timing critical application like running real-time deco profiles is a real question.
On the other hand, the cameras are quite good, and lots of folks have old phones laying around they don’t use. I definitely won’t dismiss the solution out of hand, at least for recreational divers. I could see a phone in a case being turned into an interesting camera/ dive recorder/ reference/ PDA type device for diving.
However, some of the posts here seem to assume that you would have access to similar functions underwater as you have on the surface. The physics just don’t allow for that.
Phones communicate (phone, wi-fi, bluetooth, NFC) through RF, and at frequencies that are attenuated very rapidly underwater- millimeters to inches. Basically two phones aren’t going to communicate via those methods unless the cases are touching, or unless they have some kind of intermediate communications protocol, like an acoustic modem. You are not going to send messages or get calls or emails underwater without a lot of intervening technology.
I doubt these are going to threaten dedicated dive computers anytime soon, but they could have a place, if well done and reliable.
-Ron
. I'd feel better about running a dive computer with dive software than diving a phone with some android or ios deco models. Can you imagine all the free dive computer apps that would pop up based on someone's personal model of decompression theory?
