The wind picked up as we approached launch and the torque due to the fins at
liftoff was getting pretty high, that caused the initial pitch angle and the
control PID is pretty close to critically damped, which of course needs to be
addressed, however it settled down nicely until we hit a high wind shear which
it damped out slowly again after passing through. Still she was heavily
influenced by the wind which we are addressing.
The fins on this flight were actually hurting us because of weather-cocking.
We intend to remove or reduce them in the future when we have good aero data or
modeling to tune the control part of our gnc for that condition.
Russell
-----Original Message-----
From: arocket-bounce@xxxxxxxxxxxxx <arocket-bounce@xxxxxxxxxxxxx> On Behalf Of
John Stoffel
Sent: Tuesday, March 05, 2019 11:21 AM
To: arocket@xxxxxxxxxxxxx
Subject: [AR] Re: EXOS launch
Just curious if there's any word on the waggle on launch? Was it
over-correcting too aggressively at first before it settled down because the
fins started contributing enough counter force? I was impressed that worked so
well when it looks like it was 10+ degrees off a couple of times.
Was it possible because the gimbaling is actually a bit damped for most of the
flight because the fins contribute so much centering (correct term?) force with
the CG in the proper place? But at low velocity, you don't gimbal as
quickly/aggresively to keep the thrust vector through the CG?
John
Henry> Hey, Russ - congrats! Looks like a solid operation. Looking
Henry> forward to hearing more next month at Space Access 2019.
Henry> (shameless plug -
Henry> http://space-access.org/updates/sa2019info.html)
Henry> How high did this flight end up reaching?
Henry> Henry
Henry> On 3/5/2019 9:11 AM, russ@xxxxxxxxxxxx wrote:
Henry> Well we thought of that a bit. Next flight we are going to program
the AGU (what flies the
Henry> parachute) with a collision avoidance table and the elevation
Henry> map for the area as well.
Henry> We landed a tad harder than desired because the elevation was a
couple meters higher where it
Henry> did land. Winds were quite high so it just couldn’t make it all the
way to the intended
Henry> landing point.
Henry> Still the damage was only a crack in the boat-tail, we are analyzing
the gnc right now, it was
Henry> definitely working against a high wind and we need to crank up some
of the gains, but we
Henry> finally had great gps and our ACS in rate control worked great
transitioning from high rate to
Henry> low rate. All the payloads made it back fine and we are set to go
again once we have the
Henry> tweaks in.
Henry>
Henry> Russ
Henry>
Henry> From: arocket-bounce@xxxxxxxxxxxxx <arocket-bounce@xxxxxxxxxxxxx> On
Behalf Of Anthony
Henry> Cesaroni
Henry> Sent: Saturday, March 02, 2019 1:45 PM
Henry> To: arocket@xxxxxxxxxxxxx
Henry> Subject: [AR] Re: EXOS launch
Henry>
Henry> Next time I talk to Russel, I’ll have to thank him for not landing
on my roof. Kudos.
Henry>
Henry> Anthony J. Cesaroni
Henry> President/CEO
Henry> Cesaroni Technology/Cesaroni Aerospace
Henry> http://www.cesaronitech.com/
Henry> (941) 360-3100 x101 Sarasota
Henry> (905) 887-2370 x222 Toronto
Henry>
Henry> From: arocket-bounce@xxxxxxxxxxxxx <arocket-bounce@xxxxxxxxxxxxx> On
Behalf Of Henry
Henry> Vanderbilt
Henry> Sent: Saturday, March 2, 2019 1:03 PM
Henry> To: arocket@xxxxxxxxxxxxx
Henry> Subject: [AR] Re: EXOS launch
Henry>
Henry> And, down, not at all far from the launch site, and apparently quite
gently.
Henry> Congrats to everyone at Exos on what looks like a good test flight!
Henry> On 3/2/2019 11:01 AM, Henry Vanderbilt wrote:
Henry> Chute and vehicle body starting to be separately visible,
nearing ground? Low cloud
Henry> layers in background, so nearing ground.
Henry> On 3/2/2019 10:56 AM, Henry Vanderbilt wrote:
Henry> And the rocket's in sight again, on cam but too blurry to
tell much. 'The chute just
Henry> deployed" heard. GPS tracking steerable chute apparently
working to steer back toward
Henry> the planned recovery point. (Band width to back-country NM
apparently a problem,
Henry> their feed is down to under 200 kbps now, not much vid
detail.) Still descending.
Henry> On 3/2/2019 10:48 AM, Henry Vanderbilt wrote:
Henry> Checklist continues, cam now on swivel (presumably for
tracking), and lit and
Henry> off... Looking good so far.
Henry> On 3/2/2019 10:46 AM, Henry Vanderbilt wrote:
Henry> t-2 min, vehicle pressurized. Pad very bare.
Henry> On 3/2/2019 10:45 AM, Henry Vanderbilt wrote:
Henry> Looks like they're done with vehicle prep -
they're moving the support
Henry> truck away. T-5 minutes. And a "go for launch"
poll underway.... All
Henry> "go".
Henry> On 3/2/2019 10:39 AM, Henry Vanderbilt wrote:
Henry> T-17 minutes, they just announced. (Yes,
the youtube feed is back
Henry> up.)
Henry> They also announced something interesting,
which is (I paraphrase)
Henry> that they regard this suborbital vehicle as
an excellent low-cost way
Henry> of building team skills for a future orbital
vehicle. So Exos has
Henry> further ambitions!
Henry> On 3/2/2019 10:32 AM, Henry Vanderbilt wrote:
Henry> Running a bit late. As best I can tell
from the checklist
Henry> call-and-response in the feed, they've
finished fuel-fill and are
Henry> working on LOX fill. Launch relatively
soon thereafter, I'd
Henry> guess.
Henry> Henry
Henry> On 3/2/2019 8:38 AM, Jesse Hanson wrote:
Henry> Here's the live link for the launch.
Henry>
Henry> https://m.youtube.com/watch?feature=youtu.be&v=1gRuXIGNn6s
Henry>
Henry> Can also visit the EXOS Aerospace
Systems & Technologies page
Henry> on Facebook for updates.
Henry>
Henry> On Sat, Mar 2, 2019, 10:10 Robert
Steinke <
Henry> robert.steinke@xxxxxxxxx> wrote:
Henry> Does anyone know if EXOS is
webcasting or live blogging
Henry> their launch today?