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Title: Warning: Don't use SimonK ESCs on NTM 2826 motors. Post by: hyd_quads on October 18, 2012, 10:45:16 AM 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 (http://www.rcgroups.com/forums/showthread.php?t=1513678&page=283) (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 Title: Re: Warning: Don't use SimonK ESCs on NTM 2826 motors. Post by: hyd_quads on October 18, 2012, 10:46:27 AM Oops. It's a typo: The topic should read NTM 2826 motors, not MTM. I request an admin to kindly correct it.
Title: Re: Warning: Don't use SimonK ESCs on NTM 2826 motors. Post by: abhilash_172 on October 18, 2012, 11:18:03 AM @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.
Title: Re: Warning: Don't use SimonK ESCs on NTM 2826 motors. Post by: hyd_quads on October 18, 2012, 11:20:25 AM 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 Title: Re: Warning: Don't use SimonK ESCs on NTM 2826 motors. Post by: abhilash_172 on October 18, 2012, 11:22:42 AM what about I2C esc's?
Title: Re: Warning: Don't use SimonK ESCs on NTM 2826 motors. Post by: hyd_quads on October 18, 2012, 11:27:14 AM 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.
Title: Re: Warning: Don't use SimonK ESCs on NTM 2826 motors. Post by: abhilash_172 on October 18, 2012, 11:46:53 AM 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. Title: Re: Warning: Don't use SimonK ESCs on NTM 2826 motors. Post by: hyd_quads on October 18, 2012, 11:48:38 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. Title: Re: Warning: Don't use SimonK ESCs on NTM 2826 motors. Post by: abhilash_172 on October 18, 2012, 11:55:53 AM 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.
Title: Re: Warning: Don't use SimonK ESCs on NTM 2826 motors. Post by: hyd_quads on October 18, 2012, 12:06:20 PM 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...
Title: Re: Warning: Don't use SimonK ESCs on NTM 2826 motors. Post by: abhilash_172 on October 18, 2012, 12:25:38 PM @hyd_quads yeah,what you are saying is correct.
Title: Re: Warning: Don't use SimonK ESCs on NTM 2826 motors. Post by: hyd_quads on October 20, 2012, 08:16:42 PM 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 |