SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Apr 26, 2012, 01:01 AM
Registered User
jevermeister's Avatar
Deutschland, SH, Kiel
Joined Jul 2011
509 Posts
Discussion
Short Question: Motorstutter

I searched a bit but it is hard to find the exact issue.

Maybe you guys can give me a quick hint:

When a motor is doing this at minspeed and every now and then a short hickup inflight:
Propeller hickup at minthrottle (0 min 21 sec)


When I wait long enough the motor stops completely and I have to cut off throttle completely to restart it
The hickups in flight are the bigger problem imho.

what is wrong?
All motors are configured equally via programming card:

High Timing, soft cutoff, brake off, governor mode off etc.
Only this motor is doing this. If I connect it to antoter motor channel on the FC the problem is still on this motor/ESC so it is not the FC
I use Turnigy Plush 12A, CF2822 with 10" Props.
(for the insiders: It is Multiwii 2.0 with minthrottle set to 1300)

I have the following ideas:
- I forgot to teach Throttle endpoints.
- bad solder joints
- bad ESC
- bad motor


Thank you for your help guys.

Nils
jevermeister is offline Find More Posts by jevermeister
Last edited by jevermeister; Apr 26, 2012 at 12:58 PM.
Reply With Quote
Sign up now
to remove ads between posts
Old Apr 26, 2012, 04:14 PM
Registered User
jevermeister's Avatar
Deutschland, SH, Kiel
Joined Jul 2011
509 Posts
anyone?
jevermeister is offline Find More Posts by jevermeister
Reply With Quote
Old Apr 26, 2012, 04:53 PM
Wherever you go there you are
7oneWo1f's Avatar
United States, MN, Minneapolis
Joined Nov 2011
8,440 Posts
Have you swapped ESCs/motors? This will help figure out if it is the ESC or the motor. If it is the ESC, reprogram it, or replace it.

If it is the motor, check the wiring. Do you use bullet connectors? If so, did you wrap them in electrical tape after connecting ESC to motor? (Possible short or leakage).

Do you have any wiring differences among the four motors? (Bigger current loop in this motor, or perhaps smaller)? Have you measured the power at WOT (if that is possible with a quad), and gotten essentially the same readings for all four when the hiccoughs aren't occuring? If not, there may be something physically different in the motor, or the timing is wrong in the ESC, or the voltage sensors in the ESC are shot.

Anyway, it looks like the motor is going backwards sometimes, but it is difficult to impossible to tell due to video frame rate aliasing.


On some of the ESCs I've used that spuriously run backwards at startup, I've noticed that correcting the timing does help, but doesn't fix it. It just reduces the frequency of occurrence. In this case, when I power up, and am ready to take off, I increase the throttle trim until the motor starts spinning in the correct direction. If it does not, I use a throttle cut programmed in my Tx, wait for the motor to stop spinning, then release the throttle cut. In my case, once the ESC figures out which way the motor is spinning, there are no start up hiccoughs. This works on my ESCs that have a problem similar to what you describe, but only when starting from a stopped condition.
7oneWo1f is online now Find More Posts by 7oneWo1f
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Question about Avroto 2814 short shaft Tokaz Multirotor Talk 0 Jan 05, 2012 03:49 PM
PH10 motor short wire question olmod Castle Creations 2 Nov 19, 2004 08:19 PM
long or short flybar - that is the question KasperE Electric Heli Talk 0 Aug 17, 2004 04:09 PM
E3D, first flight, cut short, gearing question... Kosh Sport Planes 9 Nov 26, 2002 07:05 AM