Stabilize, and Fly By Wire A, both performed well right out of the box with no adjustments to the PID values. Now it's on to Fly By Wire B, and Return to Launch. I don't have the airspeed sensor hooked up yet so it's relying on GPS data from the uBlox for determining speed. I set the cruise speed in the config file to a calculated value that I thought should represent flight speed at 50% throttle. However the values I was getting on my Ardustation for cruise at 50% and were higher than I expected. Then when I switched to FBW-B, with the stick at 50% resulted in lower than expected cruise speed. Obviously I have some work to do there. Return to launch worked well. there was a dramatic dive from an altitude of about 190 meters, to the desired 100 meter RTL altitude. The Ardupilot navigated it's way back home very well, then didn't exactly remain on station around the home position. It didn't want to fall in line and loiter around. Any comments anyone would care to share on these behaviors for FBW-B, and RTL would be welcome!

Views: 392

Related Videos

Comment by Nathaniel Caner on August 27, 2010 at 6:38pm
Sorry about the sound! I haven't gotten any music on my computer to add as a soundtrack yet! You might want to turn your volume down! Gets a little annoying :)
Comment by John C. on August 27, 2010 at 6:50pm
This is a ArduPilot+IMU setup, right?

Comment by Nathaniel Caner on August 27, 2010 at 7:11pm

Yes, sorry it would be useful to know that! ArduPilot V2, ArduIMU+ V2, Ardu Shield V2, and uBlox5 completed the setup

Comment by AVS on August 27, 2010 at 7:49pm
It is great to hear you didn't have to alter any PID values. When you say it didn;t want to fall in line did it always try to fly off in the same direction?

Comment by Jason Short on August 27, 2010 at 9:29pm
With that big of a plane, I would go for a slightly larger Loiter Radius. I'm also going to change the logic a bit. I've been meaning to do this. RTL will become a "loiter around home" instead of treating home like a normal Waypoint. Currently, you fly over home and THEN switch to Loiter. That sets up a bad flight pattern from the start, making it hard to hold a proper circle. I will also change the way the flow is calculated on the outside of the radius. I think it's too weak and too big.

If your plane dives too fast, try and limit your pitch_min value in the header.

Comment by Nathaniel Caner on August 28, 2010 at 3:47am

I hadn't thought about it, but now that you mention it I think it does always want to depart to the South.


Thanks for the suggestion I'll bump the radius up from 50mto 60m, and I'll Increase Pitch_min from -20 to -15.
I thought I'd seen a blog post of yours that talked about this change in RTL to loiter around the home position I assumed that was the way it was. Anyway that change would be great, I look forward to seeing it.

Best Regards,

Comment by Paul Marsh on August 28, 2010 at 5:06am

Thanks (to you and everybody else that does this) for putting in the descriptive phrases throughout your video. I love that. Many times you never really know when a plane is on autopilot, or just what's going on during the flight when watching videos, whether taken from the ground or from the air.

Comment by AVS on August 28, 2010 at 7:58am

As you know you have master jason on the case so do post when it works.

Were you using the DIYd ground station? Did it show home and all of your waypoints where you expected them to be?
Comment by Christof Schmid on August 28, 2010 at 1:08pm
Hi Nathaniel,
What version of AP software did you use?


Comment by Nathaniel Caner on August 28, 2010 at 6:29pm

No I haven't gotten the Ground Station working yet. I just bought a brand new Toshiba laptop with an 8 hour battery! Right now I'm using my ArduStation to view the telemetry. I can't wait to get the GS working though, I look forward to being able to replay the flight in GE. I visually estimated the Home position ,it was only about 25 yards in front of me. Yes it was where I expected it to be.


The version I used for this flight was AP r1401, and IMU r136. Sorry I was a little shy on details with this video. I tried to upload 4 times a 97MB file with the Flash uploader, each time it had an error, then I tried the simple uploader, and it said the file was too big? Anyway I finally reduced the size to 320 x 240 and got it uploaded. Unfortunately it got pretty late, and I'm on the I wasn't my usual thorough self.

Best Regards,



You need to be a member of DIY Drones to add comments!

Join DIY Drones

© 2020   Created by Chris Anderson.   Powered by

Badges  |  Report an Issue  |  Terms of Service