Rebreather World - View Single Post - Rate of PO2 drop changes with depth true/false

Genesis · 25th December 2006, 04:28

There's more to it than this, or the injection algo wouldn't be working as well as it is.

I'll get to the bottom of it, as this is now one of those puzzles where the math and the empirical evidence don't line up. There IS a reason for it, and ultimately it has to make sense.

BTW, I am diving my unit at 0.9 - 1.1 PO2 at depth, and at 0.5 to 0.7 above 10' (automated setpoint change; 0.5 is the maximum with unvalidated sensors, 0.9 is the best you can get with a surface validation since at the surface all you can produce is a 1.0)

Since I have the source for the K1's code (I wrote it) I can easily insert data logging to see what the deviation between setpoint and actual is, how often it happens, etc. Empirically injection events happen roughly "evenly" independant of depth (expected) and so does (by sound) the time period the solenoid is open, for a given level of work.

I'll stick some logging code into the firmware and see what I come up with after a few dives with it in there.

25th December 2006, 04:28	#9 (permalink)
Genesis Bubbless Box of Death Current Rebreather/s: Home Build Other Rebreather/s: Home Build Join Date: Oct 2005 Location: Sunny Florida Posts: 1,395	Re: why do we do it? There's more to it than this, or the injection algo wouldn't be working as well as it is. I'll get to the bottom of it, as this is now one of those puzzles where the math and the empirical evidence don't line up. There IS a reason for it, and ultimately it has to make sense. BTW, I am diving my unit at 0.9 - 1.1 PO2 at depth, and at 0.5 to 0.7 above 10' (automated setpoint change; 0.5 is the maximum with unvalidated sensors, 0.9 is the best you can get with a surface validation since at the surface all you can produce is a 1.0) Since I have the source for the K1's code (I wrote it) I can easily insert data logging to see what the deviation between setpoint and actual is, how often it happens, etc. Empirically injection events happen roughly "evenly" independant of depth (expected) and so does (by sound) the time period the solenoid is open, for a given level of work. I'll stick some logging code into the firmware and see what I come up with after a few dives with it in there. __________________ "A venturesome minority will always be eager to get off on their own, and no obstacles should be placed in their path; let them take risks for Godsake, let them get lost, sunburnt, stranded, drowned, eaten by bears, buried alive under avalanches - that is the right and privilege of any free American." http://www.denninger.net http://www.diversunion.org/liability.htm - Fix the Diving Cert racket Last edited by Genesis : 25th December 2006 at 04:30.
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