Comments

• Dr. Michael Vogt April 22, 2014 at 11:17am

  Greetings Talon-ites,

  I had a great day today. I have been flying four Talon-mini's since mid Feb2014.... most everything behaved correctly in Manual and Stabilize modes, and worked so well that it was really frustrating to have the LOITER perform poorly and in a questionable manner.... but last week, something Gustav wrote about reversing elevator made me go back through my notes as we both appear to be having the same strange behavior - reversed vtail reaction when the plane should be performing a coordinated turn to correct a roll.... so yesterday, I swapped my VTail servo cables, and interestingly, most all Manual and Stabilize Tx-sourced controls worked exactly the same, but, pitch reaction from the elevators was reversed, so I reversed this on my Spektrum DX7s Tx... and I switched VTAIL_OUTPUT mode from '2' to '3' and voila!!!!! All DX7s sourced control actions are isolated and work exactly as they should in Manual mode, and also all DX7s sourced controls work exactly as the should in Stabilize mode as well, with the VTail rudders correctly coupled to the ailerons for proper coordinated turns.... The plane also reacted correctly to my physically rolling and pitching it... now when I pitch plane down, the VTail elevators swing up to correct it... when I pitch down the VTails swing sown to correct it, and when I roll left, the plane executes a correct coordinated right turn/right roll to correct it....

  armed like this, I configured plane for FM4 - LOITER and headed to my flying field. two flights of 25 minutes each confirmed that the plane is working great even with standard default PiDs for the Roll and the Pitch control loops. I configured a second, identical Talon Mini for the same settings, and got the exact same behaviors - painlessly flying 6, 7, 8, 9, 10, 11, 12 very precise LOITER circles at about 95m AGL, with a 60m radius... no airspeed sensor, just GPS speed, and in a 5-9 MPH gusting NW wind... both planes will further improve as I have dumped the Nav_roll/Roll and Nav_pitch/Pitch and see some improvement to be made, esp in Pitch(relaxing)....
  I plan to get four more of these up and ready in the next month.... when I verify the latest updates to the PiDs ill be posting them, along with complete Rx-APM2.4.1 wiring and Tx model files.
  Thanks for all your help guys... plane is already making a wonderful ortho-mapping platform, albeit a very fast one....

  DocV
• 

  Gustav Kuhn April 20, 2014 at 7:27am

  Hi Michael,

  I've just finished uploading param files from Juan, that completely screwed my Talon RC commands :-)

  I fixed all that, obviously our radios differ somewhat.....

  In all my messing around to fix it, what I did find, is that in any "apm commanded mode", there is a function to set up "co-ordinated turns", using rudder, and that mine was actually reversed, and fighting the aileron input.......

  Could be the cause of some of the things I see during flight.

  Talon is now set up, and tomorrow I might have some answers.

  How the hec did you squeeze an APM into a Radian Pro?

  Some pictures would be nice !

  Previously I flew APM 1.5 in a ST Models Discovery, super stable, super accurate, with stock params :-)

  And then I forgot to connect the pitot.........

  Ok, my untested params...

  GustavTalon20140420.param
• Dr. Michael Vogt April 20, 2014 at 6:53am

  Gustav,

   

  I haven't charted your 'funny loiter circles' yet, but I suspect they will look like mine, something less than nice circles I get from my Radian Pro's outfitted with APM1.4's (I have at least a dozen of these built - they work great).

   

  My trouble is, the Talon-mini airframe has been wonderful...   tough to get balanced, but with 2x2200 mAh batteries in the very front these are amazingly stable airframes....launch easy, even in rough gusty winds...and they have made great look-down camera platforms for my research... but I got the v-tail mixing done all through software, and while it appears to work great in MANUAL and STABILIZE mode, even in AUTO...im not thrilled by the simple LOITER performance which I use a lot....   I suspect something amiss w the internal software v-tail mixing.

   

  I have purchased 2 different brands of hardware-tail mixers....  I had read several places cautioning people  about timing issues between the APM firmware and the latency of the hardware mixers causing some control surface 'stutter'... but I think im willing to try it anyway.  I have several of the Talon-mini's all built and flying... so I have at least one to experiment with.

   

  I am also flying the APM2.4.1, which I don't think many people have...   I may upgrade to APM2.6 for a couple of my Talon-minis and see if theres an improvement.

   

   

  Ill keep you posted, but Id be happy to share set up param files if its helpful....

   

   

  DocV
• 

  Gustav Kuhn April 20, 2014 at 5:23am

  Ignore the 2014-04-19 tlog :-)
• 

  Gustav Kuhn April 20, 2014 at 5:15am

  DocV, what strange things do you see?

  I'm wondering if it wouldn't be better to an outboard vtail mixer........
• 

  Gustav Kuhn April 20, 2014 at 5:12am

  Well, I've done two Auto missions now.

  Definately requires some tuning.

  Loiter also does some funny circles.2014-04-20%2010-03-56.tlog

  2014-04-19%2016-13-47.tlog
• Dr. Michael Vogt April 19, 2014 at 7:21pm

  greetings.    I have been using the ardupilot for several years, but have been slow to join forums and post.   in the past few months I have built and been flying several Talon-mini's, (4 of them) and have things working great.... with a couple strange behaviors in AUTO modes.... id be happy to share set ups, strategies, and such... and would welcome some feedback about V-tails and FM's such as LOITER and RTL.....  which I think are behaving incorrectly....

  DocV
• 

  Gustav Kuhn April 2, 2014 at 2:02am

  Hi guys,

  My name is Gustav, I have both the big, and mini Talon.

  Only flown the big one so far, and only in Manual and Stab mode with APM 2.5.

  3548 900KV motor, 12X8 prop, 3 X 4000mAh 3S packs.

  Found the CG should be about 10 mm back from the marks.

  Real fun plane, launch and landing quite easy.

  @ 60 Km/h mine only eats about 6 to 7 Amps :-)

  But I'm going to fit a 3548 1100KV motor.

  Any one have some PIDs they can share?
• Moderator

  David Anders February 20, 2014 at 4:13am

  The mini-talon is almost done...  Hoping to get it up in the air this weekend - assuming it doesn't rain.  I thought this was meant to be summer?!?!
• Moderator

  Gary Mortimer February 20, 2014 at 3:34am

  Aha, Christiaan has them he will send them on to you ;-)