Warning: Don't use SimonK ESCs on NTM 2826 motors.

Started by hyd_quads, October 18, 2012, 10:45:16 AM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

hyd_quads

This thread is just to warn all the DIY multirotor freaks here that simonK ESCs and NTM Prop drive 2826 motors don't make a good combination. (I think RcTimer has similar motors which should be incompatible as well).

Many people have experienced problems AND Simon Kirby himself made it clear (see the second post in this page) that it's a bad combo.
He suggested to use Wii-ESC firmware instead; someone tried it and was succesful.

Now I wonder how to convert my Simonk ESCs to Wii-ESCs.. Can anyone help? ;D

hyd_quads

Oops. It's a typo: The topic should read NTM 2826 motors, not MTM. I request an admin to kindly correct it.

abhilash_172

@hyd_quads,why are you changing your esc firmware?does it make any significant increase in response?i think by adding magnetometer to 6 dof will make quad ultrastable.correct me if i am wrong.

hyd_quads

The firmware is changed to increase the throttle refresh rate which is one of the prime steps twoards making a quad more stable. The stock firmware has some kind of a PWM filter which makes it slow (remember the board is 8 bit). SimonK firmware significantly increases the throttle refresh rate to around 450Hz.
A magnetometer is used for fixing the Z-orientation of the quad. How does it make the quad stable?

Vineet

abhilash_172


hyd_quads

They have a very high refersh rate. BUt they can't be used with the standard FCs. Ask any MikroKopter guy you know to get more info.

abhilash_172

gyro drift can be reduced by adding gps or magnetometer.i think refresh rate also depends on code frequency(pid loops).higher the frequency,response will be good
http://airhacks.org/?p=37
@hyd_quads,don't think otherwise,i am not arguing,i just wanted to know about simonk firmware.

hyd_quads

Quote from: abhilash_172 on October 18, 2012, 11:46:53 AM
@hyd_quads,don't think otherwise,i am not arguing,i just wanted to know about simonk firmware.

Hehe, I know that.
And what pid loops? We ain't talking about the FC's frequency here, but the ESC's throttle refresh rate.

abhilash_172

if pid loop frequency is high,say about 100 hz,motor commands will also be updated about 100hz,i am saying this thing ,not crystal frequency on FC.

hyd_quads

You see, our motors are not connected to the FC directly. Even if the FC updates the ESCs at a good rate, the ESCs with stock firmware update the throttle very slowly. These f/ws are for improving the refresh rate on the ESC's side, not the FC's...

abhilash_172


hyd_quads

AN IMPORTANT UPDATE

SimonK's 2012-09-30 release fixes the issue of incompatibility. So go ahead, flash your ESCs with SimonK's latest fw and use them on your NTMs.

Cheers!
Vineet