RGBM Question

[boulderjohn]

I am in the process of writing an article and need some information about RGBM usage in technical diving.

Can someone provide a RGBM profile for a dive to 200 feet for 20 minutes using 18/45 for back gas and 50% and 100% for deco gas?

I realize that there will be more than one option for this.

 

[Graeme Fraser]

Are you after an actual or planned profile? A buddy and I did a 67m dive on 18/40 BG, 32%TG and 79%DG last Spring, with Suunto Eon fused-RGBM algorithm which, if I recall, was about 20 minutes bottom time. I've since sold my Eon but I think he still has the log on his laptop.

Apologies if I'm off the mark on this, but happy to ask him to forward if it helps.

 

[boulderjohn]

I am looking for a planned profile. I will be comparing it to other algorithms. I need it to be precise.

 

[kelemvor]

I like the sound of actual comparisons between algorithms! I hope your article will be published somewhere that we of the unwashed masses can read it.

 

[Storker]

I have the impression that there's more than one flavor of RGBM. Are you thinking of Bruce Wienke's original algorithm or variations thereof, like Suunto RGBM?

 

[scubadada]

Among Cressi, Mares, and Suunto, I believe only Suunto supports trimix.

 

[Manatee Diver]

Suunto's DM5 includes dive planning. It is a little frustrating to use because at least on Mac it crashes every so often.

DM5 Support

I am not sure if they've updated DM5 for the new RGBM2 that they are releasing.

 

[boulderjohn]

I have the impression that there's more than one flavor of RGBM. Are you thinking of Bruce Wienke's original algorithm or variations thereof, like Suunto RGBM?

Every decompression algorithm I know has ways of adjusting things to your preferences. For Bühlmann, it is gradient factors. VPM has +1, +2, +3, +4, and +5 conservatism choices. I know that RGBM can be similarly adjusted. Bruce Weinke said that RGBM had gradient factors in it from the start, although he called them reductions, IIRC. I just need to be able to identify which option I am using when I identify the results.

For those looking for a full-blown comparison of algorithms, I am sorry to disappoint. The purpose of the paper is quite different. The comparison I am making is a minor point within it, which is why I am asking for such a specific profile. I don't need to know anything more about the algorithm than the answer to that specific question.

 

[boulderjohn]

Suunto's DM5 includes dive planning. It is a little frustrating to use because at least on Mac it crashes every so often.

DM5 Support

I am not sure if they've updated DM5 for the new RGBM2 that they are releasing.

I don't really need the latest and greatest. In fact, it might not be preferred, since my purpose has a touch of history about it.

 

[Manatee Diver]

Just an attempt to run it, I would suggest playing with DM5 yourself since I only know the book knowledge for tech stuff.