Holding for Weather
8/29/2007
Integration is everything
You can have all the systems complete and tested, but it doesn't count for nothing until you put them in the vehicle.
Once integrated into a larger system, subsystems can take on a life of there own. Unexpected behaviors, weird
reactions are the norm. I always assume integrating a system
will take twice as long as building the part in the first
place. The motor control system for the airship were no exception. It bench tested superbly then did all kinds of funky
things once on the airship. In spite of the frustration is caused Bob and Ross, I just smiled. Right on schedule.
Fill Tubes!
We are going to use some seven foot diameter balloons on the next mission. We haven't flown baby balloons
in a while and were fresh out of fill tubes. A fill tube is a carbon sleeve that we slide inside the balloon nozzle. They need
to sized to balloon that were using, they need to be very stiff and since they stay with the balloon that can weight nothing,
or at least as close to nothing as we can make them. It's just a little
part, one of the hundreds of little things that go into a
flight.
Here's what they look like coming off the mold.
8/21/2007
The new parachute is complete. This one is for the baby airship that will fly next month. At the end of it's mission
it will release the helium and descend on the parachute.
Today is a writing day. Not as much fun as building, but very necessary.
8/19/2007
Working The Todo List
We made lots of progress on a long list of airship tasks. The control wiring harnesses for the motor
were built and tested. All the panels on the new parachute were sew together. We cut out all the parts for
the deck that the parachute will ride on. The carbon valve/mount
was trimmed and the seams filled with
carbon paste. The electronic compass software was integrated into sensor array controller. Last, but very
important, a pile of pockets for the flapping dampening were hemmed.
It's easy to stay focused on the flashy stuff, launching the rocket, floating at 100,000 feet, etc. I'm glad I have a crew
that can stay just as focused when it comes down to the thousands of unexciting details.
Next on the immediate front:
Sew webbing lines on to the new parachute
Modify a second flow meter
Finish launch bag modifications
Complete new launch bag
Complete the second large launch bag tear panel
Make motor controller frame mounts
Write the output routine for the sensor array controller
Sell ads to pay for the mission......
PongSat Blog
The SEDS organization has graciously setup a blog for PongSat users and future PongSat users.
Stop by and say Hi! http://blogs.seds.org/pongsat
8/14/2007
The Countdown... sometime we don't know when to just put the camera down.
Here's the downloadable version:
be afraid......
The idea is that the real countdown to space start when you pick up the soldering iron.
8/13/2007
No Work, No Kirk.
We need a touch
bigger parachute for the next mission. We kept is simple and did a straight 20%
increase of the fabric templates. The fabric is cut out now
it just needs to be sewn together.
The valve/mount
for the airship is nearly done. last week the halves were joined.
Saturday a
carbon strip was run around the seams.
We thought the sensor array was done. Oh well, sometimes you just can't
leave well enough alone.
We added the digital compass. Now we'll know which way the airship is
heading. It was to be integrated
into the main flight controller. The main controller is already getting
upgraded to run the motors. Adding the
compass to the sensor array made simplified and sped up the
process.
More sewing. This first launch modifications are nearly complete. After
that there are still two more bags
to upgrade.
We got the new motor controllers talking to the motors. Now we need to
go from a nest of test wires and clips
to a flight system. and a big happy birthday
Carl!
8/9/2007
Ascender Development Path
100
foot Phase II
30 foot Rocket Deployed Mach Glider
Small Orbital Ascender
20 foot Rocket Deployed Mach Glider
900
foot Transatmospheric Ascender
Large Orbital Ascender We're
in Wired!
8/8/2007
Trades
We bumped the
duration of the motors on the airship up for the first flight. However,
it comes with a price. We traded the
video camera for batteries. Airships that fly at the edge of space have
amazingly tight weight budgets. One of the things
I do on the big airship is find a 1/2 ounce a week I can remove.
Sometimes it's changing twenty low load Aluminum bolts for
nylon ones. Sometimes it's
remolding a part with just a little more care with the epoxy. 1/2 ounce
a week doesn't sound like
much, but it really does add up.
All is not lost in the video department. We took one of the still
camera and are going to run it in video mode. We modified
the camera controller so it will shoot eight seconds of video every
minute for 200 minutes. The quality is lower than the full
camcorder however, the entire system weights 10 ounces instead of three
and half pounds.
8/5/2007
We finally
finished the motor sensor arrays, at least the hardware. The software
still needs RPM and serial data
dump routines. Along with
soldering it won't be a build session without sewing. Half of the
anti-flapping pockets were
sew on to the first large balloon bag. Only eighteen to go..........
We're considering a tether test launch with the first airship. We could
do it local and run the entire system at 100 feet.
It will give us excellent training and it always get us great
looks from the barbecuers at the park.
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