Like many others, I have been mildly obsessed with the thought of building my own autonomous aircraft for some time now, and DIY Drones has been a wonderful inspiration. It helped convince me to purchase an EasyStar a year ago, but due to other activities in my life, it sat collecting dust in its box until 2 weeks ago when I finally began to assemble it. Well, I finished it last Thursday and had a coworker help with its maiden flight to ensure that all was well. I am flying with a 1500 mAh LiPO battery, so it was tail heavy and we needed to add some ballast to the nose. Fortunately, I had my Garmin Forerunner 305 GPS watch with me, which we turned on and placed in the cockpit. It did the trick for ballast, but the recording was less than ideal.
Saturday morning came around, and it was time for my first flight of the Easy Star! The only plane I had previously flown was 2 channel Firebird Commander 2 from Hobbyzone, and I had serious butterlies since I was now moving up to a "real plane"! I learned from the maiden flight that the GPS watch should be set to record data every second instead of at automatic intervals, so with this correction in place, I hand launched the plane into the beautiful 60 degree air and slowly felt my butterflies disappear as I gained confidence in flying the plane. All in all, I was out there flying for nearly an hour on that single battery charge, and according to my recorded flight details, about 40 minutes was actually spent in the air. I have to say that everyone who has claimed tha the EasyStar is a wonderful flyer was right on the money! Not only was it money well spent, but I can't wait to outfit it further with aerial photography add-ons and finally with the ArduPilot!
But back to the GPS! Once I got home, I uploaded all the flights to Garmin's MotionBased website where you can play back animations of the recorded paths. Check out the final flight of the day
, which consisted primarily of unpowered gliding after the battery voltage got too low. Be sure to choose Satellite and Large within the Google map frame, select the playback speed to be 0.5x or 1.0 x, and hit the Play button!
And if that isn't enough, I was able to export the path to a KML file for 3D viewing
in Google Earth! There were two tricks to get this to work properly. First, the MB Gravity Elevation Correction had to be disabled as part of the Activity Options within the MotionBased website. Otherwise, it uses a digital elevation model to estimate the elevation assuming that you are running or biking and would never be 200 feet off the ground! Second, in Google Earth, I had to set the Altitude Property for the path to be Absolute, so that it would be projected in 3D above the Earth. Now I want to figure out how to use the built in flight simulator to fly the path!
Sure I don't have an autonomous plane yet, but I already have a successfully flying platform and have performed beautiful navigation recordings, and that's an encouraging start!