September 5, 2004 notes:
Rejected NASA NOI
A couple years ago someone pointed me at this image:
From the NASA history:
I thought, Hey, that looks rather like our manned lander
Since then, I have often commented that something along
those lines would be an excellent mobility tool for lunar or Martian exploration. NASA recently put out a request for proposals
for Human and Robotics Technology (H&RT) programs to further the current
lunar directed exploration directive, so I decided to go ahead and make a
It took a couple of readings to wade through all the
acronyms and make some guesses at what they were actually looking for, but it
seemed reasonably in line with what we are working on. The submission process starts with sending a
Notification Of Intent (NOI) to submit, which included a 700 or so word summary
of the project and some information about the deliverables. After the NOI, you make your full submission
proposal, and they decide which projects get funded through a two-stage
It turns out I probably underestimated the importance of the
NOI. We planned to hire a professional
to write the full proposal, because we dont have enough (any) experience with
NASA expectations, but I thought the NOI was just to see if we were even
looking in the right direction.
My summary in the NOI:
Rocket powered ballistic roving is a technology with
applications for both manned and unmanned transportation on both the moon and
mars. Even modest ballistic vehicles
could provide rapid transportation over lunar ranges of hundreds of miles, and
cover terrain impassible to ground vehicles.
Over the last four years, Armadillo Aerospace has
independently developed several generations of vertical takeoff, vertical
landing rocket ships ranging in size from forty pounds to over two thousand
pounds. Our work so far has focused on
hovering translations and strictly vertical ballistic paths, but we propose to
use our existing technologies to rapidly and cost effectively produce a proof
of concept demonstrator capable of point to point transportation and return. Our existing systems could be considered TRL
5, but they are not directly applicable as is.
An example of a recent vertical soft landed ballistic flight
is at: http://media.armadilloaerospace.com/2004_06_15/perfectBoostedHop.mpg
An example of an older man-carrying ballistic vehicle is at:
For an initial demonstrator, the primary unique challenges
will be in modifying our flight control software to maneuver and thrust along
ballistic trajectories with soft landings, and designing a robust vehicle
configuration to survive the test program.
Our ongoing efforts at improving operability and manufacturability would
continue with this vehicle.
Initial testing with the demonstrator would show multiple
destination hops in the several-hundred-feet range, with a return to base for
refueling. Speed and range would be
kept low enough to prevent it from becoming an aerodynamics experiment, but
still cover enough range to adequately demonstrate the concept. After an initial boost at moderate
acceleration, the engine would be throttled down to still provide attitude
stabilization until it is time to do the landing burn.
A trade study of various propellant combinations and vehicle
configurations for an efficient lunar design would also be conducted, with
extrapolations from the operation of the demonstrator vehicle giving greater
confidence in the results.
We could pursue several different directions for phase II, and
we would like feedback on which directions NASA would find most fruitful. A truly space capable demonstrator could be
fabricated and tested. A manned vehicle
could be demonstrated. A telepresence ballistic
rover could be operated in a lunar analog environment.
Moving to a different engine technology would require some
effort on our part. Our current
vehicles use jet vanes under a single mixed-monoprop rocket engine, but we also
have experience with 90% - 98% hydrogen peroxide monoprop and peroxide /
kerosene biprop engines, as well as attitude control by dedicated thrusters or
symmetric differential throttling. We
do not have any experience with cryogenic propellants.
Our current guidance system uses GPS to handle drift in the
IMU that we use. For proof of concept
demonstrators this should be acceptable, but we would need to move to a higher
end IMU for a true lunar capable vehicle.
We do not have experience in vacuum operation of our
systems, but we plan on enclosing what we can in pressurized compartments.
Moving to bladder tanks may be helpful to the project.
Armadillo Aerospace is not an established government
contractor, and our development approach will be considered unconventional, but
we feel that we can provide excellent value to the program. Our small team has a diverse composition,
representing minorities, women, and veterans, and two team members are also educators.
Your Notice of Intent (NOI) entitled Ballistic Rover
Demonstartion has been reviewed by NASA.
The Agency received a tremendous number of NOIs (over 3,700) in response
to the H&RT BAA. Unfortunately,
only a relative handful can be accepted to proceed to full proposal
preparations. Your NOI was determined
to be very good and demonstrated acceptable understanding of requirements and
approach that meets performance or capability standards. The NOI has no major
weaknesses, several minor weaknesses, but sufficient strengths to balance and
compensate for the minor weaknesses.
However, only NOIs rated as excellent or higher were invited to submit
Therefore you are not requested to submit a full proposal
for the Human and Robotics Technology BAA.
Please continue to monitor our website for future
opportunities. On behalf of the
H&RT Program we thank you for your participation.
Program Executive Officer
was a bit disappointed at this, but I would rather get the brush off now
instead of wasting a month and some money to prepare a proposal that would be
The list of all the NOIs that they did accept (about 500):
of paper studies will be made, but it will be interesting to see how much actually
gets built in the next few years.
We are still waiting on the tank for the new vehicle, as
well as the machined manway flange and the rolled nose cone assembly. I went ahead and ordered a second Crossbow
IMU, so we should have a complete backup electronics system sitting on the
We are still having problems with the 7 engine
combinations, and we have nearly exhausted the possible permutations we can
make with them. The latest builds will
run smoothly for about five seconds, then go unstable, apparently when the hot
pack reaches a certain temperature. We
could use the engines in their current form, but we would have to limit the
throttle to a certain level to keep them running smooth. We have a few more things to try, but all
this aggravation is pushing us to look at biprops again.
Unstabilized 70% peroxide / kerosene with a cat pack and
spark igniter is still the best bet for us, because we can still use the
polyethylene lined tanks, and it should be easy to deep throttle. While peroxide is normally shipped around at
70% concentration, it isnt usually repackaged at that concentration. I may need to buy an entire tank car load to
get it. We have been setting up our old
1000lbf aluminum biprop chamber for some tests in preparation for
I dont think nitrous oxide offers much for us, because it
is more expensive than peroxide, and offers worse system performance when you
include the heavier tanks that are necessary at ambient temperature.
We may yet build a LOX engine. Im not sure any LOX engines have ever been demonstrated with a
5:1 or greater throttling range, but Charles Pooley proposed the interesting
idea of making a lox preburner that vaporized all the lox before mixing most of
the fuel, which gives a gas / liquid main combustion, which should throttle
just like our cat-pack peroxide biprops.
We still think cryo propellants are something to be avoided if possible.
One of the things I had been thinking about in the context
of the NASA submission was a purely gaseous hydrogen / oxygen rocket, which
could easily use the presumed polar ice deposits. You would probably also inject some water for extra cooling and improved
mass fraction. We built a few
experiments to play around with this while we were between tests of the 7
mixed monoprop engine. Separate
injection of hydrogen and oxygen gave hot spots as the mixture ratio varied,
but a coaxial injector worked great, and barely got hot during operation. We set up our old 1 ID water cooled chamber
and made a little rocket engine out of it.
It was an excellent demonstration of engine critical pressure, because
we started by cranking the hydrogen pressure all the way up, then turning the
oxygen pressure up. It would start out
as a fluffy blow torch, but as the oxygen was cranked up, it got louder and louder
until the chamber reached critical pressure, at which point it instantly
switched from a blow torch to a rocket engine with mach diamonds. We might use a small combustor like this for
a lox vaporizer.