Drosophila-nator (Prototype)

This is a joint Entomology / Aerospace project to look for evidence that Spotted Wing Drosophila (an invasive species to North America) may be migrating at higher altitudes where wind currents can carry them further and faster than otherwise expected.

Skywalker 1900 outfitted with 2 petri-dish sized insect traps.

Skywalker Flight #69

Altitude: 200′ AGL
Airspeed: 20 kts
Weather:  10 kts wind, 22C
Mission: Circle fruit fields with insect traps.

Skywalker Flight #70

Altitude: 300′ AGL
Airspeed: 20 kts
Weather:  12 kts wind, 20C
Mission: Circle fruit fields with insect traps.

Skywalker Flight #71

Altitude: 400′ AGL
Airspeed: 20 kts
Weather:  13-14 kts wind, 20C
Mission: Circle fruit fields with insect traps.

Flying on the Edge of a Storm

This is a follow up to my eclipse post.  I was forced to end my eclipse flight 10 minutes before the peak because a line of rain was just starting to roll over the top of me.  I waited about 20-30 minutes for the rain to clear and launched a post-eclipse flight that lasted just over an hour of flight time.

Here are some interesting things in this set of flight videos:

  • You will see the same augmented reality heads up display and flight track rendering.  This shows every little blemish in the sensors, EKF, flight control system, and airplane!  It’s a great testing and debugging tool if you really hope to polish your aircraft’s tuning and flight performance.
  • IT IS WINDY!!!!  The skywalker cruises at about 20 kts indicated airspeed.  Winds aloft were pushing 16 … 17 … 18 kts sustained.  At one point in the flight I record 19.5 kt winds.
  • At t=2517 (there is a timer in seconds in the lower left corner of the HUD) we actually get pushed backwards for a few seconds.  How does your autopilot navigation work when you are getting pushed backwards by the wind?!?  You can find this about 20 seconds into Part #3.  Check it out. 🙂
  • In the 2nd half of the flight the winds transition from 16-17 kts and fairly smooth, to 18-19 kts and violent.  The poor little skywalker is getting severely thrashed around the sky in places.  Still it and the autopilot seem to handle it pretty well.  I was a bit white knuckle watching the flight unfold from the ground, but the on board HUD shows the autopilot was pretty relaxed and handled the conditions without really breaking much of a sweat.
  • When the winds really crank up, you will see the augmented flight track pass by sideways just after we pass the point in the circle where we are flying directly into the wind  … literally the airplane is flying sideways relative to the ground when you see this.
  • Does this bumpy turbulent video give you a headache?  Stay tuned for an upcoming video in super smooth air with a butterworth filter on my airspeed sensor.

Note: the hobbyking skywalker (1900mm) aircraft flown in this video has logged 71 flights, 31.44 hours in the air (1886 minutes), and covered 614 nautical miles (1137 km) across the ground.

Flying on the Edge of an Eclipse (2017)

On August 21, 2017 a full solar eclipse sliced a shadowy swath across the entire continental USA.  The totality area missed Minnesota by a few hundred miles so we only saw about 85% obscuration at our peak.

I thought it could be interesting to put a UAV in the sky during our partial eclipse and record the flight.  I didn’t expect too much, but you never know.  In the end we had a line of rain move through a few minutes before the peak and it was really hard to say if the temperature drop and less light was due to a wave of rain or due to the eclipse.

Still, I needed to test some changes in the AuraUAS flight controller and was curious to see how the TECS system would fly with a completely unfiltered/raw/noisy airspeed input.  Why not roll all that together and go test fly!

Here is the full video of the 37 minute flight.  Even though this is slightly boring flight test video, you might find a few interesting things if you skip around.

  • I talk at the start and the end of the flight.  I can’t remember what I said, but I’m sure it is important and insightful.
  • I rendered the whole live flight track in the video using augmented reality techniques.  I think that’s pretty cool.
  • If you skip to the end, I pick up the plane and walk back to the runway.  I think that is the funnest part.  There I pan the airplane around the sky and show my flight path and approach drawn right into the real video using the same augmented reality techniques.
  • We had 100% cloud cover and zero view of the sun/moon.  But that doesn’t stop me from drawing the sun and moon in the view where it actually is.  Not surprisingly, they are sitting almost exactly on top of each other.  You can see this at the end of Part 3.
  • I flew a fully autonomous landing on this flight.  It worked out pretty well and shows up nicely at the end of Part 3.  If anyone is interested, the auto-land task is written as an embedded python script and runs right on-board in the main flight controller.  I think that might be pretty cool for people who are python fans.  If you want to geek out on the details you can see the whole landing script here: https://github.com/AuraUAS/aura-core/blob/master/src/mission/task/land2.py  (Then go watch it in action at the end of Part #3.)