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Electronics => Electronics => Topic started by: airman00 on May 03, 2008, 07:07:50 PM

Title: Overpulsing servos
Post by: airman00 on May 03, 2008, 07:07:50 PM

If you overpulse a servo , would it go faster or break?

For example if the maximum rated pulse is 2ms then what would happen if I gave it 3ms , or if I gave it 6ms?

At what point would it break , or maybe it wouldn't go faster at all??

thanks,
Eric

Title: Re: Overpulsing servos
Post by: Admin on May 03, 2008, 07:55:37 PM

Every servo is different . . .

My limited experience is that analog servos go the same speed, but they vibrate more and overheat. I'm guessing that digital servos don't care.

Wouldn't hurt to try and report back :P

Title: Re: Overpulsing servos
Post by: airman00 on May 03, 2008, 08:03:47 PM

Quote from: Admin on May 03, 2008, 07:55:37 PM

Wouldn't hurt to try and report back :P

sorry I don't really have any spare servos I can trash  ,lol


so I guess I shouldn't overpulse analog servos

Title: Re: Overpulsing servos
Post by: izua on May 03, 2008, 10:13:22 PM

as far as i went, they go about 0.5ms in each extreme.
i haven't tried more, though.

Title: Re: Overpulsing servos
Post by: Admin on May 04, 2008, 06:54:43 AM

izua, which servo?

the micro-sized futaba servos, like the S3114, can't do less than 10ms without the overheating

Title: Re: Overpulsing servos
Post by: izua on May 04, 2008, 08:28:06 AM

Some inexpensive aeromodelling (http://phoenixmodels.ro/shop/product_info.php?cPath=21&products_id=785) ones. They were overheating even with minimal loads..:P

Title: Re: Overpulsing servos
Post by: TrickyNekro on May 04, 2008, 08:38:24 AM

well, there is a change of speed but it's not even noticed...
Is it modified servos of not for continuous rotation...
If they are... no problem.... if not... you are damaging the inner of the servo... gears and trimmer...
Is it a analog or a digital servo...
If it is analog it will work for sure... if it is digital... the have some rejection limits... above them or below them respectively they do not operate...

supply these information first and then ask...
But generally over pulsing a continuous rotation servo is no problem...
When the servo is unmodified there is a problem...

Lefteris

Title: Re: Overpulsing servos
Post by: airman00 on May 04, 2008, 10:15:42 AM

I have an analog modified servo

so you're saying overpulsing it would not result in any noticeable change in speed?

Title: Re: Overpulsing servos
Post by: TrickyNekro on May 04, 2008, 11:07:04 AM

Yes... and you will not get problems like overheating either....
You will get like a rad or two but no more than five per minute...
If speed is to be considered... well over pulsing is an option then...


Cheers,
Lefteris

Title: Re: Overpulsing servos
Post by: paulstreats on May 04, 2008, 04:54:27 PM

I dont think that over pulsing changes speed. If you want a faster servo you need to use a digital servo, I reade a guide about 2 weeks ago from either futaba or hitec(cant remember which) basically digitals give a better speed response because the pulses sent to the motors are a lot shorter but a lot more frequent, this makes them stronger and faster.

I might be mistaken by what you mean by overpulse though? do you mean on a modified servo? to make it go faster? if so then probably not, you are still better with the digitals. Unfortunately its got to be a trade off against price and quality..

Title: Re: Overpulsing servos
Post by: TrickyNekro on May 05, 2008, 06:27:51 AM

Quote from: paulstreats on May 04, 2008, 04:54:27 PM

I dont think that over pulsing changes speed. If you want a faster servo you need to use a digital servo, I reade a guide about 2 weeks ago from either futaba or hitec(cant remember which) basically digitals give a better speed response because the pulses sent to the motors are a lot shorter but a lot more frequent, this makes them stronger and faster.

I might be mistaken by what you mean by overpulse though? do you mean on a modified servo? to make it go faster? if so then probably not, you are still better with the digitals. Unfortunately its got to be a trade off against price and quality..

It doesn't changes the speed notably...
1rad/min as I said above is so 3^o per sec.... literally nothing, but there is a change...