New Inspiration scrubber.HUD & integrated controller

[DrySuitDave]

Fellow turtle divers,

I was talking to Cliff at Silent Diving Systems the other day, and he said they are taking pre-orders (hasn't that always been an oxymoron?) next week for the new Inspiration larger capacity scrubbers, new lids, new wristmount O2 controller and integrated deco computer along with the new HUD. The HUD by the way is driven by the existing cells, not a 4th cell, so secondary calibration issues should be eliminated.

As most know, the wrist computer will have an C02 driven LCD bar graph to allow you to monitor the scrubber duration.

The guys at SD sure are a bunch of knowlegable, helpful guys.

 

[DrMike]

APD told me last month that the conversion kit wont be available for 12 months???

Thats what I call pre-pre ordering!

 

[MikeR]

That was my understanding as well, 12 months or longer.

 

[caveseeker7]

Hi Dave,
got a couple of questions regarding your post:

DrySuitDave once bubbled...
... the new Inspiration larger capacity scrubbers, new lids, new wristmount O2 controller and integrated deco computer along with the new HUD.

What are the specs on that scrubber, amount of absorbent and duration rating?
Asuming that the new scrubber contains the sensors, does that mean if you want extra duration you have to upgrade the electronics, and if you want the new electronics you need to upgrade the scrubber?

From what I understood from Nicky's presentation at DEMA, the new controller (Evo's) ist just a primary display, with the HUD replacing the secondary. Deco software(s ?) is an option.
What prices did they quote for scrubber, head/display assembly, and deco software?

And in regards to the taking of pre-orders, when will they deliver the order?

DrySuitDave once bubbled...

As most know, the wrist computer will have an C02 driven LCD bar graph to allow you to monitor the scrubber duration.

Actually it's a temperature driven LCD bar graph, the actual CO2 isn't measured. Scrubber condition is inferred from the temperature/changes inside the scrubber bucket.

 

[DrySuitDave]

I figured anyone who dives CCR was techy enough to know that C02 wasn't directly measured, but the thermal gradient within the stack was being monitored via an axial thermistor.

Cliff only mentioned the scrubber had a larger capacity. That could mean 1 ounce, though, lol. No specs yet. It always appeared to me that there was several inches in depth the scrubber could be extended and still fit within the case.

The scrubber is entirely new with a new head with the 02 sensors in it I was told. I was left with the impression that 3-4 months would be the delivery time but you know how manufacturing goes.

The wristset is the primary display and the HUD the secondary display. Now since I have Bob Howell's righteous OC/DSV, hopefully the HUD bracket will still fit as it appears it mounts to the final threaded collar that screws to the side of the DSV.

 

[pipedope]

has a system to actually measure CO2.

Not a lot of detail as the patent process and setting up to get to market requires a bit of secrecy at this point.

It will be interesting to see when more word comes out.

 

[Genesis]

... is not impossible, but so far its been very difficult to do (1) accurately, (2) for a long period of time, (3) with reasonable economy and (4) in a reasonable size and power consumption package.

Doing so by chemical absorbtion is quite trivial, but that's a "one shot test" rather than a measurement on an ongoing basis.

It would seem to me that the cat's meow would be a fuel-cell type apparatus that would work on CO2 instead of O2, or some similar kind of sensor. The problem with most of the ways I can come up with to do it is the power consumption; totally unreasonable for something like a rebreather.

Note that actually doing so is NOT impossible as some have claimed by any means - the Apollo missions had CO2 measuring devices, including analog meters, in the capsules.

 

[pipedope]

but not much.

As I understand it the problem with measuring CO2 in rebreathers is the high humidity in the loop.

Tom Rose is (I think) using a system that measures the absorbtion of light to measure CO2.

 

[Genesis]

The humidity would not really be a problem, since its nearly constant (assuming the solenoid is not firing) - its close to 100% all the time!

Its VARYING humidity that screws things up.

Absorbtion methods have, until now, been problematic due to power consumption and the spectral requirements to make it work. It will be interesting to see how he has solved those problems, as they're critical for this kind of application.

The reason the O2 sensors work so well in a CCR is that they're self-powered - you need only sense a voltage, not drive some active device. As such the power consumption is very modest, as the largest drain is the O2 solenoid.

 

[padiscubapro]

DrySuitDave once bubbled...
I figured anyone who dives CCR was techy enough to know that C02 wasn't directly measured, but the thermal gradient within the stack was being monitored via an axial thermistor.

Cliff only mentioned the scrubber had a larger capacity. That could mean 1 ounce, though, lol. No specs yet. It always appeared to me that there was several inches in depth the scrubber could be extended and still fit within the case.

The scrubber is entirely new with a new head with the 02 sensors in it I was told. I was left with the impression that 3-4 months would be the delivery time but you know how manufacturing goes.

The wristset is the primary display and the HUD the secondary display. Now since I have Bob Howell's righteous OC/DSV, hopefully the HUD bracket will still fit as it appears it mounts to the final threaded collar that screws to the side of the DSV.

I cant see how they could increase the scrubber length in the current case.. sure there is plenty of length available but if the make it longer they have to increase the diameter otherwise they will increase the breathing resistance.. they can go a little but without any noticable effect...

The navy did studies back in the 50s on optimal ratios and scrubber shapes, if my memory is correct the current ratios is near optimal..