TBS Discovery / Pixhawk or APM PID Tuning

[clouseau]

Originally Posted by Big Island Guy

This is very interesting, because I was having some issue with powering my Dragom Link RX through the power bus on the Pixhawk (my new one) too. As I was getting ready to come up here, I didn't have a chance to chase it down with proper measurements, but I'm gonna have a closer look when I get back. I ended up using power from one of the ESC BECs for it.

If you look up the specs on the power module, it's only 5.3V @ 2.25A max. I wouldn't even trust an regular receiver on it. But I don't think they ever meant for it to power anything other than the Pixhawk unit itself.

[chad2323]

Hi Sean this is Chet that posted on your you tube channel thank's for sharing your setting should have my Pixhawk in a few days.

[Big Island Guy]

Originally Posted by clouseau

If you look up the specs on the power module, it's only 5.3V @ 2.25A max. I wouldn't even trust an regular receiver on it. But I don't think they ever meant for it to power anything other than the Pixhawk unit itself.

I'm sure you're right. Oh well, no harm done.

[flyhigh999]

Hey guys just got my pixhawk/TBS Discovery Pro setup and flying.

What frame type you guys using for the Discovery? The X or V?

[SeanM]

I'm using the v frame option.

[badfrog]

just finishing a build of an Extreme Spyder

Spyder Extreme FPV Hexacopter (1 min 28 sec)

and received my Pixhawk late last week.
I have been reading reading reading all I can find about the Pixhawk. My initial plan was set it up with my DX8, but now plan to fly it with a Futaba 14SG. I have been reading about setting the Pixhawk up with Sbus and it seems that there are still issues with the 7008 receiver that came with the 14SG... any one have experience with Pixhawk/Futaba SBus?? I did order the PPM encoder board, so if push comes to shove, I may set it up with that although I would like to learn the Sbus setup and use it (my understanding is that the SBUS is besides being "one wire" it is a "faster" connection as well).

I am looking forward to learning all their is to know about this controller and using/applying all its great features!

[Big Island Guy]

Originally Posted by badfrog

just finishing a build of an Extreme Spyder Spyder Extreme FPV Hexacopter - YouTube
and received my Pixhawk late last week.
I have been reading reading reading all I can find about the Pixhawk. My initial plan was set it up with my DX8, but now plan to fly it with a Futaba 14SG. I have been reading about setting the Pixhawk up with Sbus and it seems that there are still issues with the 7008 receiver that came with the 14SG... any one have experience with Pixhawk/Futaba SBus?? I did order the PPM encoder board, so if push comes to shove, I may set it up with that although I would like to learn the Sbus setup and use it (my understanding is that the SBUS is besides being "one wire" it is a "faster" connection as well).

I am looking forward to learning all their is to know about this controller and using/applying all its great features!

I'm using a UHF system on my 14SG with all my birds now, but can tell you that the SBUS was really nice to use on my S800, once I figured it out. A nice thing is that you can mix and match with the ordinary outputs, so for example, I had the regular outputs going straight to the WKM which sat right next to it and then the SBUS with decoders for the more physically distant stuff like the pilot cam's pan-tilt controls. I can't give you any advice on Futaba/Pixhawk I'm afraid though.

[Big Island Guy]

I finally got around to inputting the gains you were kind enough to share here Sean. Boy, were mine off by a country mile! Good thing I never tried to do anything more than check that the motors spin the right way. If we can get some decent weather (it rained 4" here today), I'll give her a whirl real soon.

[SeanM]

I too was surprised by how much different my numbers were compared to what the auto tune came up with. Were you using the stock values?

Let me know how the settings work out for you once you get it in the air. This is on your disco pro, right?

[Big Island Guy]

Originally Posted by SeanM

I too was surprised by how much different my numbers were compared to what the auto tune came up with. Were you using the stock values?

Let me know how the settings work out for you once you get it in the air. This is on your disco pro, right?

Yes, my settings were stock. I never really had a chance to mess with them before I left for Seattle. And also yes on the Disco Pro. Even though it's not exactly the same, I figure your numbers will be a good baseline to start from. Way better than theirs for sure! Thanks again for sharing them. I'm sure they've saved me a lot of time, crashes etc.

[jubalr]

Hi Sean,

I've been following your thread and really appreciate your efforts and sharing. I have an 800 size hex with the APM 2.6 and the TBS Disco with the Pixhawk. I love the way the hex flies but haven't been able to dial in the Disco the way I think it should be. I've put in you values and it flies better than it has but there are 2 values it won't accept. The Imax in yaw and loiter both max at 327. When I put more than that in there and write, when I refresh they have been changed to 327. I don't know that it would make much difference. The trouble that I am having is in the Loiter mode. It just seems a little jerky, and like it's always hunting. It's great in stabilze and alt hold modes. I have done the calibrations in compass and accel. I have attached my values for reference.
Thanks

[Big Island Guy]

Sean, all my numbers are plugged in right, I've been through all the little dances, but this thing just wants to act crazy, as if the ESCs were totally uncalibrated. It's like there's either full throttle or nothing, with little or no in between. TBS says that if you use their Bulletproof ESCs, which I am, then there's no need to calibrate them, but I'm wondering if that's assuming a Naza controller. Did you have to calibrate yours? (If anyone else has info, feel free to chime in.)

[SeanM]

I did follow the ESC calibration steps in the YouTube video below. I would try it if you haven't already, even though TBS says that no calibration is necessary. I believe this step is actually teaching the FC your throttle range, based on your ESC choice.

[ame]http://youtu.be/gYoknRObfOg[/ame]

[Big Island Guy]

Thanks very much Sean for the link! Yeah, everything else is accounted for and the way it's acting is just what one might expect if the ESCs weren't properly set up. I'll be sure and follow up with the results. :

[SeanM]

Anytime BIG, hope that helps.

[Big Island Guy]

Hmm, I cannot seem to get any indication of it going into ESC calibration mode. With the props off, I can get some throttling action, but with them on, it's either nothing or it it instantly screams to life and flips on its back. Worse yet, while I was testing with the props off, one of the motors started spazzing and some smoke came out. At this point, I think I'm gonna pull it off the Disco Pro and use it on something dirt cheap until I can figure out what's going on and then vet it further to see if I trust it with expensive stuff. That's what common sense should have told me in the first place before sticking it on an expensive bird like the Disco Pro. Luckily, it's undamaged.

[SeanM]

Do you have all three ESC wires plugged into the Pixhawk, or just signal and ground? There's also a manual method, rather than the all at once method, which should work if the all at once method fails.

http://copter.ardupilot.com/wiki/ini...tup/esc-motor/

This sounds very similar to what clouseau was experiencing with his opto 30A DJI ESC's, which also are not able to be calibrated I believe... The link above does mention that some ESC are simply not compatible.. It would be nice if they had a list somewhere.

If all else fails, I would pick up a set of 20-30A Afro's from Hobbyking... I'm using the 20A and they don't even get warm.

[Big Island Guy]

Thanks Sean. The manual method you were nice enough to link me too is what I want to try next, but it was 2 AM, so I figured I'd call it a night. After I put it on another frame, I'll do that though. Interesting about the ESCs. I should have thought to ask which ESCs you're using. I'm using the TBS branded Bulletproofs. Since yours seems to have done what it's supposed to, I'll probably end up ordering a set of those Afros. (Although I will try the manual method first) As always, thanks for sharing the info! :
P.S. Almost forgot, yes, only ground and signal wires are running between the ESCs and controller.

[SeanM]

Here's a video from this weekend.. I haven't changed any of the PID values in a while, but I'm finding that I might still have a little yaw tuning to do. Anyway, I'm really happy with how this video turned out.. I have a new level of confidence now, thanks to FPV and the Pixhawk. I thought I would be a little more nervous flying over water, but I didn't sweat it one bit. It was a blast, with stunning views I might add.

[ame]http://youtu.be/FJ6yc3ScE4I[/ame]

[hANDYman]

Hey Sean,

That's a great video! Looks like you were quite far away at times. Are you using a standard Tx/Rx, or a UHF setup? I'm not sure of the range of a standard Spektrum radio, and maybe it looks further in the video than it really was.