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Gaza07:
22 Aug 2019 22:47:32
Sorted mate  ~~
Andy7:
22 Aug 2019 10:27:36
Sure. But basically, all the subjects are getting cut off.
Gaza07:
21 Aug 2019 18:14:54
Can you pm me a screen shot of what you mean
Andy7:
21 Aug 2019 12:15:41
Gaza - can you make the subject line section in the forum topic list wider? It's cutting off the subject field really short.
Andy7:
19 Aug 2019 09:14:20
Good for you!  ~~
DarkButterfly:
18 Aug 2019 19:13:57
Had another negative encounter, it's been a few years since the last one, just an uneducated ******, going on about drones being illegal yada yada yada.    :-/
Still that didn't spoil my flying time, had an absolute blast  ~~
Gaza07:
07 Aug 2019 19:52:01
ooooh mrs jones  :D
hoverfly:
30 Jul 2019 15:26:34
D.B. you tightwad.. :cool:
atomiclama:
29 Jul 2019 20:14:10
DB that just means you have shed loads of props in the first place ;-)
DarkButterfly:
29 Jul 2019 18:53:33
Just had a thought, even with all the crashing I've done, I haven't bought any replacement props in over a year ~~
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3d - Printworx

Printing 3d Forum

Bunnygirl's : Alexmos Jittering at Extremes and How-to Stop!

Started by bunnygirl80, Saturday,July 27, 2013, 08:06:35

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bunnygirl80

Saturday,July 27, 2013, 08:06:35 Last Edit: Tuesday,August 06, 2013, 03:27:38 by bunnygirl80
Okay, I was going to post this on my custom TBS Gimbal thread, but then thought it was relevant to a few of you. You might have noticed that when the gimbal is moved very quickly and fiercely or when the gimbal reaches it extremes the motors flutter.

I didn';t bother with this too much on my large hex and just assumed that was the way it was! WRONG!

On my custom built TBS gimbal, I have the same alexmos board, but not in any rush! So, I decided to have a play with the settings and try to understand them a bit better. After watching these two very useful videos, I discovered that increasing the motor power and the D of the PIDs stops the fluttering.

PLEASE MAKE SURE YOU HAVE CALIBRATED YOUR IMU IN ALL SIX AXIS!!!
VERY IMPORTANT.



I also wanted to move my IMU out of the way to the back of the gimbal and this is a good video on how to do this.



Always smile because you never know who could be falling in love with it. :) Drone Operator in North Wales. www.aerialworx.co.uk

Rafter

Thanks for this Stef, very informative, gives me confidence to start twiddling me knobs.

Peter

bunnygirl80

Quote from: Rafter on Sunday,July 28, 2013, 17:12:10
Thanks for this Stef, very informative, gives me confidence to start twiddling me knobs.

Peter


No worries Peter. They are two very useful videos.
Always smile because you never know who could be falling in love with it. :) Drone Operator in North Wales. www.aerialworx.co.uk

ChrisH

Stef, I';ve just got mine set up, impressive! At the extreme of roll the gimbal flips back 20 or 30 degrees and then carries on normally until you exceed a certain angle then it bounces back again! I';m totally new to the PID concept, can you point me to a setting that may stop this? :hmm:

Otherwise it works well "out of the box".  ~~

Solved that one, treated it like your jitter and upped the motor power. Now can roll well past the limit of the Naza and no jumping!
Chris
Hubsan X4
DJI F450, Naza, GPS, DX8,
Tarot FY680 Naza, GPS, Hero3 Silver, 5.8 FPV with screen
 :england:

ChrisH

I';m using the same channel on my DX8 for the knob and want to vary the camera pitch. Is there something to enable this in the GUI? :hmm:

No reaction from the gimbal ATM. :whistling:
Chris
Hubsan X4
DJI F450, Naza, GPS, DX8,
Tarot FY680 Naza, GPS, Hero3 Silver, 5.8 FPV with screen
 :england:

bunnygirl80

Quote from: ChrisH on Saturday,August 03, 2013, 18:34:21
I';m using the same channel on my DX8 for the knob and want to vary the camera pitch. Is there something to enable this in the GUI? :hmm:

No reaction from the gimbal ATM. :whistling:


Hi Chris,

No, just plug two servo cables from 2 spare channels on your RX to the gimbal controller. Make sure you have setup the TX knobs first. You can do this by just plugging an old servo into the receiver first. Once, you';ve done this you can have manual control over the gimbal to change it default position during flight. Very handy!

Stef
Always smile because you never know who could be falling in love with it. :) Drone Operator in North Wales. www.aerialworx.co.uk

ChrisH

Thanks for that Stef, basically what I thought. When you say two spare channels does this control both tilt and roll?

I';ll attack it again tomorrow. Do you know where to get the "Instruction book" that is referred to several times? I';ve been to several sites including the SimpleBGC site with no joy!  :hmm:
Chris
Hubsan X4
DJI F450, Naza, GPS, DX8,
Tarot FY680 Naza, GPS, Hero3 Silver, 5.8 FPV with screen
 :england:

ChrisH

Sorted. The Tx mode needed to be PWM, the default was Analog (this is the 2.2 version?). All working now.  ~~

It';s very slow to change the angle, I thought you changed the "I" for that but it is still slow. No great problem!  :hmm:

This was a bit odd as I';d tested the Rx channel by plugging a servo in it. That worked fine but no reaction from the gimbal until I changed the Rx type!!
Chris
Hubsan X4
DJI F450, Naza, GPS, DX8,
Tarot FY680 Naza, GPS, Hero3 Silver, 5.8 FPV with screen
 :england:

bunnygirl80

Quote from: ChrisH on Sunday,August 04, 2013, 16:04:46
Sorted. The Tx mode needed to be PWM, the default was Analog (this is the 2.2 version?). All working now.  ~~

It';s very slow to change the angle, I thought you changed the "I" for that but it is still slow. No great problem!  :hmm:


Hi Chris,

Glad to hear you';ve got it sorted. Regarding the PID';s these are only for the speed that the gimbal controller will return the gimbal to level. They do not have an influence on the speed of the roll and pitch speeds that you put in from your tx. I think this is hard coded in the software and not something you can currently change.

Manual! What manual? LOL. Not seen it matey. Everything I know I learnt, so a manual might be useful to fill in the blanks! Let me know if you find one.

Stef
Always smile because you never know who could be falling in love with it. :) Drone Operator in North Wales. www.aerialworx.co.uk

ChrisH

Think the manual must be ';in development'; like several pages on their web site! The ';six axis'; calibration says see the manual for details  :smiley:

Like so much of this hobby, thank goodness for the friendly and knowledgeable pioneers on forums like this!  ~~

Has anyone posted an idiots guide to PID and the effects they have? I';m one idiot that sure could use it!  :hmm:
Chris
Hubsan X4
DJI F450, Naza, GPS, DX8,
Tarot FY680 Naza, GPS, Hero3 Silver, 5.8 FPV with screen
 :england:

bunnygirl80

Tuesday,August 06, 2013, 03:48:12 #10 Last Edit: Tuesday,August 06, 2013, 22:09:10 by bunnygirl80
Hi Chris,

I';ve not found any good instructions on this, but setup my own PID';s a few times now. I find that this is the best way.

Do all this before you perform your six axis calibration and level calibration.

1. Launch the GUI on your PC and connect to the Alexmos
2. Go to Advanced tab and turn off the pitch output
3. Go back to the Basic tab and set all PIDs for Roll to 0 and also Power to 0
4. Click Write
5. Click Auto in the Motor Configuration box to discover your polarity and poles
6. Set power to 50 and write
7. Your gimbal should oscillate as there is no correction via the PIDs
8. Increase your P for fast oscillations at a rate of 2 each time until the oscillations stop and write
9. Increase your D for slow oscillations at a rate of 2 each time until the oscillations stop and write
10. If your gimbal is slow returning to level then increase the I at a rate of 0.1 each time and write
11. Tap your gimbal with your finger to test how well it levels. If it jitters or wobbles at its limits, then increase the power at a rate of 10 up to 255. 100-150 is usually good
12. Tap again and adjust with steps 8-11 until you';re happy.
13. Do this all again for the pitch axis, but with roll axis disabled.
14. Then activate both pitch and roll axis.

You should be able to violently rock the quad from side to side as frantically as you possibly can and it should correct with no problems ALL THE TIME. It should feel like a good workout! LOL.

The process above takes me about 1-2 hours from start to finish.

Hope this helps,

Stef
Always smile because you never know who could be falling in love with it. :) Drone Operator in North Wales. www.aerialworx.co.uk

ChrisH

Thanks for that clear guide Stef!  ~~

I ended up ringing Simon to see if he had any ideas. Very helpful indeed. Thinks the board has somehow got corrupted and offered to reload it for me. I mentioned trying to get it working for the NW meet and he offered to send another board to get me going while he checks out my board!

DesireRC - more Customer Service than you can shake a rotor at!! :smiley:
Chris
Hubsan X4
DJI F450, Naza, GPS, DX8,
Tarot FY680 Naza, GPS, Hero3 Silver, 5.8 FPV with screen
 :england:

bunnygirl80

Hi Chris,

Aw! Super. Yes, Simon is very friendly and always willing to help. Great guy!

Stef
Always smile because you never know who could be falling in love with it. :) Drone Operator in North Wales. www.aerialworx.co.uk

ChrisH

Put the replacement board on. Discovered the board on bluetooth. GUI connected straight away. 2.2 comes loaded with a default to suit the RCT gimbal and GoPro. Got slight shaking on the roll which I';ll have a play with using your guide Stef but basically seems to point to a board problem. Sending the original back to Simon for him to reload and hope this works for the weekend!
:crossfingers: :crossfingers: :crossfingers:
Chris
Hubsan X4
DJI F450, Naza, GPS, DX8,
Tarot FY680 Naza, GPS, Hero3 Silver, 5.8 FPV with screen
 :england:

TheMightyThor

hello all

I have a small bounce happening on my Pitch when my gimbal slows to a stop. would i be right in assuming, increase power, increase D, decrease I

thanks in advance