Hyperbaric

Looks more like one of those sensory deprivation things.

The (banana) curved door could not possibly stand pressure.

radman:
I was in a one man chamber once, all steel, outward opening, its emergency communication system was a hammer.
If you had a problem you could attract attention!

Sounds like one of the drager coffin jobbies..... they give me the willies!

Theres a trend in sports for hypobaric chambers (for increased red blood cell generation), so I wonder if the widget above is related to that. They typically max out at ~6500M ASL.

Anyway, Im of the opinion sites like this are great when people offer advice on the design/coding. Often people plan to use arduino as a stepping stone/quick prototyping approach, rather than a final design.

Sounds like one of the drager coffin jobbies..... they give me the willies!

I don't know if was made by drager but its nickname was "the coffin".
It was one man and portable so they could pressurise you, sling you you in a truck and cart you off to hospital.

I was just in it for fun. It was very claustrophobic and the outward opening door did give me the willies.
To be injured and transported in it by road would have been hell.

Until now I have never really thought about the "coffin" name.
I took it to arise from the confined space, hopefuly nobody actually died in the one I was in.

From what I could investigate, the thing in the picture is not a hyperbaric chamber at all. It's an armchair with roof, a door and a TV. That's it.
http://www.mccormackdesign.co.uk/design/ovei-pod

It's an "Ovei pod," a phenomenally expensive "micro-environment," fitted with a fancy sound system, a video system, though that system would have to be small by today's standards, and dressed up with some comfy stuff, including its own air conditioner. It looks like the standard model runs about 100K USD. Some sites describe it as a little isolation room specifically for gamers. At that price, it would be less expensive to build a very nicely equipped 60 m2 media room.

Engadget says that it's "not for claustrophobic or poor people."
Here's a blurb: http://ifitshipitshere.wordpress.com/page/140/

I can't find any suggestion that the Ovei pod is able to support a pressure differential in either direction. The mention of gas valves suggests that the OP may be contemplating an oxygen-rich, rather than hyperbaric, environment.

Whatever is contemplated here, it should be done with care, and with a thorough understanding of all the issues and risks involved, or not done at all.

[Edit: Deleted redundant text.]

Hyperbaric is more lile pushing air into a sealed vessel. The traget pressure is 4.5 psi and I need to regulate the speed pressure increase. I found some accurate pressure sensors but I was looking to automate the speed of compression and decompression.

That's, what, 30 000 Pa of overpressure?
So, 1,3 atmosphere. If my calculation is correct, that's around 85 000 N of force on an opening with 60 cm diameter (something a person might crawl through). I would not mess around with those forces and the thing pictured in your first post most definitely could not withstand that pressure, even if you could seal the door itself.
Controlling the pump and a release valve is doable with arduino, but not advisable for this purpose in DIY method.

Okay, okay, I confess, somebody really knows who I am.

Once, when I was young, I went into an inflated building. It had no structural integrity, the internal air pressure was simply more than the external and that kept the whole structure upright.

For fire regulations all doors had to open outwards. Of course you do not have a single door in a pressured environment you have a double one.

Yes, yes it was me =( =( =( I opened both doors !!!!

This was not intentional I went through one door then the next.

I know, I know, the entire building started to collapse - it was stupidity of youth and entirely unintentional ( just like the problem with the train which we shall not go into here )

Anyway the overpressure could not have been too great and once the internal fans kicked in to try an stop several hundred people being suffocated a small army of people managed to force one small door closed against the remaining pressure which could have not been to large.

Radman, the pressure in that sort of inflatable buildings is usually around 250 Pa. That's far, far away from 30 000 Pa drfpoulin is mentioning.
The last such inflatable structure I was in was a tennis court (well there were 4 or 5 of them inside) and it had revolving doors so you didn't have to worry about releasing all that air.
The pressure differential could be felt once you enter, but certainly nothing uncomfortable. Sort of like what you feel when driving down a mountain road from higher to lower altitude.

@drfpoulin, please refrain from including off-topic links in your posts.

tmd3

I can't find any suggestion that the Ovei pod is able to support a pressure differential in either direction. The mention of gas valves suggests that the OP may be contemplating an oxygen-rich, rather than hyperbaric, environment.

Whatever is contemplated here, it should be done with care, and with a thorough understanding of all the issues and risks involved, or not done at all.

I echo tdm3.
If you are going to use oxygen then this requires special valves, oxygen is not something to be played with.
So some clarification please.
The flow of what gas are you aiming to control?
At what pressure are you aiming to do it.

There are probably you-tube videos that show experiments on what effect even a few % increase or decrease in oxygen content of the atmosphere can do.
Nature has settled on 21.5% in the atmosphere for a very special reason.
Tom.
I'm not sure how old you are but NASA blew three perfectly good astronauts up because of oxygen enriched environment.

drfpoulin:
Hyperbaric is more lile pushing air into a sealed vessel. The traget pressure is 4.5 psi and I need to regulate the speed pressure increase. I found some accurate pressure sensors but I was looking to automate the speed of compression and decompression.

is that 4.5psi OVER atmospheric, or absolute 4.5psi (eg ~1/3 ATM)?

Either way, I'd suggest you engage the services of a professional to help here, theres a lot more aspects to this than the relatively simple arduino+actuator bit (ie the answer to your original question was a yes)

  • Mechanicals; as you've probably guessed theres considerable doubt that the pod is capable of handling a pressure differential.
  • Medical; Putting aside the obvious DCS implications if its sub atmospheric, theres other risks (HACE/HAPE), dental, sinus/ears etc etc. I'd guess from your username you're well aware of that
  • Fire safety; if you're planning a hyperoxic environment there are a number of regulations that come into play, dependent on your market (eg CGA/OSHA stuff in the US)... and theres best practise too.

Incidentally, is the plan just to do a 'me too' project on the CVAC?

Good luck anyway, as long as you're informed or engage informed consultants you at least know where you are.

There should not be any medical concerns regarding that overpressure. The increase in pressure is equivalent to diving three meters under the surface of water.
It's mechanical stuff that won't hold up.

The lower (conservative) partial pressure limit for oxygen toxicity is 0.3 bar - breathing pure oxygen at three metres for prolonged periods would be a Bad Idea.
Breathing it at only six metres could be fatal.

OP did not mention pure oxygen.

regulate the air flow inside the unit

pushing air into a sealed vessel.

Breathing it at only six metres could be fatal.

Remember Hans and Lotte Hass, they pre-dated Cousteau bring diving onto TV using oxygen rebreathers.
I would presume that would not be pure oxygen, though their dive depths were limited.

I'm imagining this is being used for serious video gaming.

-Comfortable chair
-Sound system
-Display
-Isolation

I also imagine that those things don't seal up tight, but that the air would get stale if you're in there for more than 30 minutes.

Perhaps the OP is trying to build a setup that will just get some fresh air (not pure O2, but just pump in air from the room the pod is sitting in) into his gaming pod. I imagine that unless you have a seriously powerful pump & put a different seal on the door you won't ever get to that 4.5psi above ambient.

Perhaps the OP is trying to build a setup that will just get some fresh air (not pure O2, but just pump in air from the room the pod is sitting in) into his gaming pod.

If that was the case, there would be no reason to create such a high pressure differential. So, I think it's safe to assume that this is NOT what OP wants to do.

Thank you all for the abundance of replies.

I appologize for the lack of clarity.

What we are trying to acheive is a 1.3 ATA internal pressure. Roughly 4.5 PSI. This is comparable to a 3m dive approximately. We do not plan on using anything but ambiant air. I own a hyperbaric chamber of that sort. We are just trying ou another form factior which woul allow us to work on our computer while receiving a hyperbaric tratment.

This has nothing to do with hospital high pressure pure oxygen vessels.

In this example of a similar use case they are using a vertical vinyl chamber which can obviously withstand the pressure

I would like to come up with an exhaust solenoid valve which I could us to regulate the speed of inflation and deflation. http://www.jaksa.si/ has such valves..