Happy Fathers Day to all the Dad's out there today!
I had a great day at the field yesterday with a new airframe, the Blitz RC Super Sky Surfer. With a 95" wingspan and a 6.25lb total weight fully loaded this is a big lazy plane! It has a cruising speed of apx 30-35 Mph and a duration of apx 15 minutes on two parallel 3S 2200mah batteries.
APM 2.5
uBlox LEA-6H
Airspeed
Attopilot 90A
MinimOSD v1.1
3DR 900MHz
Arduplane 2.73
I've been trying to tune the plane for better navigation, but I'm having some trouble getting it to respond crisply when flying a box in moderate winds. Yesterday there was a steady wind from the N-NE averaging around 8 mph and the orientation of the field runs N to S. The box pattern has WP1 to the South WP2 East from WP1, WP3 is North from WP2, and WP4 is West from WP3 closing the box. The segments from WP3-WP2 and WP4 to WP1 are parallel to each other.
When I enter Auto (about 50% of the way through the tlog) I start near WP3, the plane tracks well to WP1 then way overshoots, over-corrects, turns back on course to WP2 just in time to hit WP2 then slightly overshoots WP2 and turns back well on course to WP3. It reaches WP3 and turns well onto the course to WP3. The turn at WP4 is pretty good, then it wanders a bit on the way to WP1 in the tailwind. This is the pattern that is repeated for the rest of the flight till I exhaust the battery and need to land.
I have attached a copy of the tlog as well as a copy of the parameter file. Below are a few screenshots comparisons of roll speed during FBW-A Max Bank,roll speed during AUTO, roll to nav-roll during AUTO, Mission planner Way Points 1-4, and a Google Earth plot of the Auto portion of the flight including the Elevation profile.
Any feedback or suggestions on that I can do to improve navigation would be appreciated.
Screenshot from the MP with North at the top.
Google Earth View with Elevation profile. The arrow is at the start of the Auto portion of the flight. It maintains altitude fairly well with a deviation of around 50-60ft min to max. What can I do to tighten this up?
Comparison of Roll Attitude vs. Commanded Nav Roll. The first two left turns show a Nav Roll at max Bank of 50 degrees, but the Roll response is slow to reach Max Bank
Plot of Roll (value of 1=apx 60deg/sec) during Auto. To me it looks like the mean is about .5 which looks like I need to increase ROLL2SRV_P from .7 to perhaps .9?
Comparision of roll speed vs Bank Angle (max) during CW and CCW turns in FBW-A.......oops looks like I cut off the bottom of that pic! Oh well didn't lose anything important.
Replies
I just got one of the Blitz RC Super Sky Surfers today and am looking forward to moving my APM 2.5 over from a HK Phantom Wing to the Surfer. Should be an amazing bird for FPV. The Phantom is OK in calm air but has a weird yaw oscillation in strong winds. You don't even notice it from the ground but behind the goggles it's annoying. The Phantom has served me well but it's time to move on.
How is yours flying Nathaniel? Did you get it tuned out well? Hope you are still following this thread, will send PM.
I shall follow this with interest as I have set one of those up this week. As an aside, are you using the stock power setup and did you replace the spar which is almost heavier than my current airframe on its own.