What are your thoughts about our constant buoyancy BCD ?

[geoff w]

After reading the comments above and perusing the web site and patent, I'm not sure what problem this solves for a diver. I have air in my BD, let some air out so I start descending, add a touch of air to become neutrally buoyant for my dive, swim around for an hour or so underwater, ascend and add air to my wing so I don't sink on the surface. The only time I usually fiddle much with air in my wing is if I'm in shallow (5 to 20 ft) water, there's a lot of surge, and I have a little air in my wing.

However, for someone with a big heavy underwater camera setup, or maybe even a DPV, I could see how having object always be neutrally buoyant would be beneficial for a diver. How small can this thing be made? Small enough to form an camera platform with 2 handles that can mount lights? That's where I see the real benefit to this. Maybe add some stabilization at the same time to counteract surge to make it easier to take better underwater photos and videos

 

[cerich]

i am concerned you cant manually inflate...you are most likely to need to do so when you are on the surface and out of gas...

 

[C Dub]

I'm a brand-spanking-new PADI Open Water certified diver. I don't see any use for this at all. A gear solution for a skills problem is spot on, in my very limited and inexperienced view. And I do assume this would be targeted to less experienced divers.....

I love gadgets and drop cash on them. This would not get me to open my wallet.

 

[Kharon]

The day I am willing to trust my buoyancy to an automated mechanism (mechanical or computerized) will be the day I stop diving. I have no desire for a Darwin Award.

 

[jadairiii]

Or maybe this one from 1968:

There was a third model sold by White Stag and Imperial (not sure who made it) that was a hard shell "bladder" that rapped around the tank, but it was not a true "constant volume". Early 70's, they show up on ebay occasionally.

---------- Post added August 15th, 2014 at 09:44 AM ----------

View attachment 191249

1976 model.

A dive with the Dacor Nautilus CVS - Blogs - ScubaBoard - Scuba Diving Forum - Diving Social Network

That's it! I have a copy of the instruction manual. You needed 3 arms to use it and better have it fully inflated at the surface or there was no way you were getting out of the water with 50lbs of water on your back!!

 

[captain]

You lost me. If it has constant volume, then it has constant buoyancy. That doesn't seem useful.

While it's true that a 3mm suit doesn't change buoyancy much, the world is not just 3mm suits. Many people wear 5 or more, which definitely changes buoyancy.



The buoyancy (and pressure) change is greatest in the shallower depths. At 3ATM, buoyancy changes are minimal and your device would have no real purpose.

I'm still not certain what this is supposed to do or why and I have read your web page.

flots.

From what I can understand of the operation it is essentially a fixed volume container that air is added to. Adding air to a fixed volume container will not change buoyancy.
You can do the same by by using a fixed volume container of a specific volume. If I am 10 pounds overweighted then a fixed volume container with 10 pounds of buoyancy with get me neutral. However it won't compensate for wet suit compression at any depth. Hope you didn't spend much money on this.

 

[DuboisP]

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Diodon

 

[billatcam]

I looked at the patent article & this is a fun idea. Kind of elegant - higher pressure air in the flotation devices (tubes) so that the system is less sensitive to changes in ambient pressure. Even when your neoprene is compressing and expanding, you would need a whole lot less adjustment with this system than with a conventional low pressure bladder.

Concerns that I would think about before buying/trying:

1) What are the modes of failure apart from "out-of-air" - flotation tubes, valves, connectors ?

2) How do you respond to a failure ? The conventional BC is sooo simple -- if it's a problem with source air, blow it up orally - and that probably covers 90% of the modes of failure in the conventional design. This device, not so obvious. It needs intermediate pressure. How do you handle an out-of-air distressed diver who is wearing this rig ?

3) How does the diver stabilize on the surface ? What is the max lift of the device ? And note that the lift is going to be pushing the surfaced diver's face down, similar to a wing -- difficult for inexperienced or distressed divers, particularly in rough water.

4) When this system vents during an adjustment with the slide switch, it will be venting gas at some higher than normal pressure, maybe near constant somewhere around 50psi (guessing). Is that going to be a different experience than normal ambient pressure venting on a BC ?

But - cool thinking. Well done.

 

[kayak-ray]

"Interesting comment and a problem we have given considerable thought to. There are 4 bladders. If any one of them should develop a leak, it becomes sealed off from the other 3 which continue functioning normally." Stated in post #9.......

I have two questions.....

Question 1:

If the above scenario were to happen would the inflation of the other three cells cause the diver to end up fighting an unwanted roll or some other undesired attitude in the water since filling of the remaining bladders would cause uneven distribution of air in the BC?

Question 2:

Again with reference to the above comment from post #9, if this happened would this equipment continue to function as intended with 25% of its lift capacity disabled ?

 

[eelnoraa]

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