June 6, 2004 notes
Streamlined vehicle fabrication
Putting the new test vehicle together has taken a bit longer
than expected, but we are almost finished.
The electronics have been significantly reworked so that the
batteries are all off the main board, freeing up enough space to lay the A/D
breakout board and GPS board down flat instead of vertical, and also leaving
space for a new custom A/D breakout board with static protection and ring
terminals that we are building.
I am unifying various connections and equipment between the
full size vehicle and the small vehicle, including finally moving over to 500
psi transducers across the board. We
had previously used 1000 psi transducers for most things, but none of our
future vehicles are expected to exceed 500 psi tank or chamber pressure, so it
is nice to double the output voltage range, which halves the signal noise.
Our GPS base station also arrived, so I will be trying to
integrate the differential corrections into our telemetry stream soon.
All the gear on the vehicle base is finished, we just need
to insulate the engine and test everything out.
(a picture before everything was completed)
We used the same axial o-ring sealing arrangement for
mounting the valves and engine to the tank that we used in the big vehicle, but
because the entire flange closure is aluminum on the small tank, we were able
to put good, thick o-rings in instead of the tiny ones we had to settle for on
the big vehicle. This lets us slide the
entire base into the vehicle and just bolt the base to the tube sides, with the
plumbing sealing itself without putting any stresses into the valves or
requiring a flexible connection.
The vehicle is going to have to land almost perfectly to
avoid tipping over, but well see how it goes next week
We will be doing hover tests on Tuesday to
see how the new vehicle and software changes (predictive throttling to smooth
out acceleration hunting) work out, then heading out for boosted hops on
Saturday if it isnt too muddy.