The Titan CCR
From BubbleSeekers
Recently at Inner
Space 2006, Tomar Gross and Larry Shreve unveiled their prototype eCCR, the
Titan. The units design is pointed at
the recreational CCR market and hits the target rather nicely. Keep in mind this unit is the first
generation pre production and as such is not in a finished condition. This may remind some of the state of the
original Optima CCR and that cleaned up nicely.
The unit is quite compact and its size and weight certainly lend it in
the direction of the traveling diver.
Weighing in at a lean 49 lbs including steel 13cf cylinders and full
Extendaire scrubber, it is a breeze to throw on and go diving. A single back mounted counter lung keeps the
chest area clear and all fittings inside the housing.
Lets get into how it works.
The gas flow is
American conventional, fresh gas comes over the divers right shoulder and into
the injection molded DSV, through the mushroom valve to the diver and back out
through another mushroom valve and over the divers left shoulder. There is a bulkhead fitting on the housing of
the unit that connects the exhale hose with an extension hose that feeds the
exhaled gas into the bottom of the scrubber canister, which is a modified
Extendaire scrubber system. The
Extendaire system is orientated in a vertical fashion, and this placement has
not been tested for duration as of this writing.
The very lightweight and
low profile DSV.
Back side of DSV showing the ambidextrous HUD
mount and shutoff knob.
This is the view from
behind the divers left shoulder with the cover removed from the unit, showing
the bulkhead connector with the extension hose attached. The breathing hoses on this prototype are of
1” ID, I have been informed that this will be moved up
to 1.25” in the production unit.
Here is the
Extendaire canister out of the unit, notice the extension hose fitted into the
bottom of the canister, the three sensors installed into the mixing tower, the
rectangular plug near the top facing lid, (ready for an ADV) and the two quick
connect fittings on the side of the top of the canister (bottom of the picture)
for plumbing in O2 and diluent.
Back
to the gas flow… After the divers exhausted gas enters the
bottom of the scrubber, it is fed into the solid Extendaire scrubber cartridge
and the CO2 is removed. At the top of
the scrubber, installed into the lid, are two solenoids, one for oxygen and the
other for diluent. The diver can fire
either solenoid from the handset to add either dil or
O2 and the computer can fire the O2 when it decides the loop needs it. The gas then travels up into the mixing tower
and into the counter lung, which is affixed to the top of the
scrubber housing by a threaded nut and sleeve, similar to how the Classic Kiss
RB attached the CL to the head. The O2
sensors are located in the top of the mixing tower, inside the counterlung. The
last path is from the counterlung to the inhale hose through another bulkhead
connector on the housing.
Back side of the unit, very
sleek and compact. The housing is
manufactured from vacuum formed ABS plastic and is quite light. 4 stainless steel locking latches hold the
back cover onto the main unit and can be touchy to fit up as the ABS flexes.
Front side, pressure
gauges fed through neoprene sleeves on the shoulder straps is a nice
touch. Easy to find,
no clutter.
Back side with cover removed. Counterlung is made from a food grade poly
and has three fittings in it, the bulkhead that feeds the DSV, the fitting that
threads onto the mixing tower, and an small OPV (over pressure valve).
Ok, lets go into some more detail. At the top of the scrubber housing we
mentioned some solenoids, take a look at how they are situated.
I am told that the
right angle swivel fittings thread directly into the solenoid bodies to help prevent
leaks into the housing. The solenoids
are rated for 500,000 cycles and these exact units have been going strong
throughout the testing and building process.
The oxygen solenoid is protected from debris by a 60 micron filter that
is fitted between the QD and the 90 deg swivel.
The wiring from here heads out to the HUD and the computer through two
bulkhead connectors, shown below.
You can also see here
the detail of the base of the mixing tower and the nut to hold the counterlung
in place. The holes in the mixing tower
are where the gas from the solenoids gets mixed with the returning gas from the
scrubber while entering the counterlung.
Here are the quick connects for the diluent
and oxygen. The hoses are made to be
just long enough to reach the proper fitting, so no mixing up dil and O2.
Regulators are from XS Scuba.
The two cables from
the top of the scrubber housing go to the computer handset and the HUD
controller, lets look at the HUD first.
This is the HUD
controller, a simple black box, potted, with an internal non replaceable
battery. This will be changed to a unit
with a replaceable or rechargeable battery for production. The single piezo button
controls power as well as a calibrate mode.
The unit can only be calibrated in oxygen and will show cell failure (by
continuous alternating color flashing) if calibration is attempted in air. The unit reads the millivolt
output of the sensors from the tower (the HUD controller is wired in parallel
with the computers sensor input using high impedance Op-amps so each sensing
device will not interfere with the other by pulling a load on the sensors.)
A long push on the
button will toggle power to the HUD system. While on, three quick pushes will enter
calibrate mode and will store the “divide by” values to convert the raw millivolt output of the sensors into a more useful number,
PO2. This value is then converted into a HUD readout of 3 flashing LED’s. The LED system is similar to other HUD
systems, notably the Will Smithers system of 1.0 =
one orange flash per sensor, anything above 1.0 providing a green flash per
sensor, example 1.1 is one green flash per sensor, 1.2 is two green flashes per
sensor. Any value below 1.0 is
represented by a red flash and one flash per each point below 1.0, example .9 =
one red flash, .8 = two red flashes. The
improvement here is that the HUD display has 3 tri-color LEDs,
one for each sensor. Instead of one LED
handling all three sensors with a pause in between, this display shows us data
continuously from all three cells. The
HUD is a stand alone piece and the only commonality between it and the computer
is the three sensors.
The three LEDs
encapsulated into clear plastic on the HUD, which swivels to either side of the
DSV.
On
to the computer…
The computer is a two button, 3 line display
with a menu system and built in mixed gas decompression. The display here shows, across the top line,
Depth, Bottom time, Stop Depth and Stop Time.
The second line shows the three PO2 values of the three sensors. The bottom line shows what mode the computer
is in, either OC or CC, then the gas mixture it is using to calculate
decompression, the No-Decompression Limit in minutes (basically a countdown
before deco) and the Time to Surface, which calculates in ascent time plus all
required deco stops between where the diver is in the water column and the
surface. The buttons are “Menu” and
“Confirm” and allow scrolling through the different menus, including “Turn
Off”, “Calibrate”, “Dive Setup”, “Dive Log”, “System Setup”, and inside those
menus are “Define Gas” and “Auto Setpoint” adjustments which allow the computer
to automatically change setpoint based on what depth the diver is at. Also are backlight adjustments, time and
date, etc. Personally I would rather see three buttons, which would allow backing
in and out of menus rather than getting bounced out and have to cycle all the
way around if you pass a desired menu or miskey. This system, manufactured for the Titan by
SRI, is designed with wet switches, to turn on the unit once it is in the water,
as well as lock out menus that should not be used while diving, such as
calibration and power off. The two blue LEDs at the top of the display show when the solenoids are
being fired, either by the computer or by the diver. This is a feedback system from micro switches
in the solenoid itself that show if the solenoid physically moved, not just if
the voltage was applied, but doesn’t, however, confirm that gas was injected,
just that the solenoid opened. LED’s
light blue if diluent is injected and green for oxygen. The next photo shows the divers interface to
the solenoids, the left, blue button is for diluent, the right green, for
oxygen, following the standard for lean left, rich right.
Another feature of
the computer is the wet mate connector that fits the unit to the
rebreather. Shown
below.
The computer housing
has two internal batteries, which are recharged through the wet mate connector
with a separate charger. The batteries
are of a Lithium Polymer technology.
There are two, one exclusively to fire the solenoid and one to run the
computers power needs.
Good Stuff:
Nicely put together
size wise and overall platform, takes any BCD and harness with no mods. Industry
standard cylinders and regulators assure you wont get stuck somewhere with no
spares. Having deco info on your CCR
controller is great, the ability to take the same dive computer on an OC dive
and keep all your tissue numbers is better still. Rechargeable batteries in the handset insure
that the diver can’t screw up the computer seal by trashing the O ring in the
battery housing. Extendaire cartridges
are becoming more popular and Micropore will ship anywhere so you can have your
scrubber at the dive site when you get there.
Ease of scrubber change out, no granules or associated
packing headaches. Gas injection on the handset, neat idea, lift
your arm up and hit the button, no grasping for buttons on your chest or valve
hanging off somewhere else.
Not so good stuff:
I’m not sure the wet
connector on the computer will survive repeated connections, especially in a
salt water environment, there was some corrosion on
the connector when I looked at it. Larry
mentioned they were looking for a better connector, hopefully not fischer. Not being able to manually inject o2 or
diluent (dil side would be fixed with the ADV) with a
non electronic pushbutton. There are too
many failure points between the buttons on the handset and actually getting o2
into the loop, switches, battery, wiring, QD on the handset and the solenoid
itself. If the cable gets unplugged, you
lose all control of the rig on your back. I wonder what the controller would do
with your deco if all sensors went to zero’s?
The HUD LED’s are
very small and might be difficult to see, I understand that if the PO2 drifts
into a bad mix, the LED’s get brighter in response. Although the Extendaire canister system has
lots of benefits, duration and cost versus granules are not two of them. I believe, for the market this unit is aimed
for, the Extendaire system is still an advantage though.
I hope this gives the
reader a good overview of what could be a great new system. Time will tell and we will keep you
posted. Any errors or ommisions are most certainly mine, contact me if you have
any questions about the article, contact Larry or Tomar at bubbleseekers(at)hughes.net They are located in California.
Ron Micjan
1 June 2006
Vancouver WA