Twitching KO RSX One10

[Cliveyp]

I’ve recently picked up a used KO RSX One10 servo for my TC. On bolting it in tonight I noticed it has a shake.....nothing major, it’s pretty much all taken up in the general slack of the steering joints, but it’s still there. It also seems to still be there if I add a bit of lock too - although does initially calm down when you first hit lock - but if you hold a steady amount of lock it twitches.

I’m running a HW XR10 Pro, so I’ve tried swapping to 7.4V BEC but this changes nothing.

Any one experienced this before? Any ideas what might solve it?

[tyreman]

I’ve recently picked up a used KO RSX One10 servo for my TC. On bolting it in tonight I noticed it has a shake.....nothing major, it’s pretty much all taken up in the general slack of the steering joints, but it’s still there. It also seems to still be there if I add a bit of lock too - although does initially calm down when you first hit lock - but if you hold a steady amount of lock it twitches.

I’m running a HW XR10 Pro, so I’ve tried swapping to 7.4V BEC but this changes nothing.

Any one experienced this before? Any ideas what might solve it?


It states on the side of the box that this is normal. Nothing to do with the rest of your electrics.

[Cliveyp]

It states on the side of the box that this is normal. Nothing to do with the rest of your electrics.


Unfortunately I don't have the box.....what does it actually say?

[mark christopher]

It's normal :thumbsup::p:p

[ianjoyner]

If you have the model selector you can also put it in mild mode, it’s still fast but smooths it out and reduces twitching at centre.

http://www.racing-cars.com/pp/Product_Category/Full_List/KO61029.html

[Cliveyp]

Thanks all. I'll give it a whirl as it is and see if the twitch actually worries me when driving. Judging by the comments of it being 'normal', i'm presuming it wouldn't.

I still find it quite amazing that KO have produced a servo that twitches 'as standard'......quite phenomenal!

[MattW]

Sanwa had one as well that did the same. I ran them for a while and never noticed. The issue is servo / pot (or encoder) hunting. It's very common in industrial servo systems (CNC machines etc) where by the servo doesn't ever manage to hit true "zero" when not loaded.

For example it's +0.001 when it's aim is 0.000. It tries to move to 0.000, but instead over shoots and ends at -0.001, so then it tries again to get to 0, guess what, over shoots and is back at +0.001 again! It keeps doing this and hunting around the centre point.

[AmiSMB]

I have found that sometimes soft mounting them helps as it this can be because it hits a resonant frequency of the servo that is altering the pot signal hence the shakes.