Asked — Edited

Max # Of Servos Without Jitter

I am new to this and I havent my ez-b yet to test it. Ive researched online and discovered that some boards are capable of many servo connections, there is a problem with efficient software routines to prevent jitter due to # of servos and other processes in the programming. I intend to use 14 servos and prob all the DIO. DJ, do you think this will be a problem?


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Well I'm not DJ but I think I might be able to add some insight as I have used 17 standard servos with the EZ-B. Now when you talk about jitter do you mean like extra vibration when moving servos or twitching servos when held in position under load?

I have experienced servo jitter when using cheap lower quality micro servos under quite a bit of load. But with standard servos that are much better quality and higher torque the jitter should only be to a minimum if any at all.

Personally I don't think the way servo routines are written has much to do with jitter but the quality of the servo and it's torque capabilities when held in position.

If you are worried about smooth response as servos move into position, you have definitely come to the right place because DJ's code doesn't send servo commands all at once but rather one after another extremely quickly such that you would be hard pressed to notice when the first and last servos starts to move. He has done a beautiful job of optimizing this response, it's actually quite crazy how far it's come.

Just wanted to add that make sure you have a battery (or external supply) that can handle the load of 14 servos because you'll need a pretty decent battery to handle that kind of discharge rate. For example the minimum would be a 7.4V 2500mAh LiPo with discharge rate of 2C which means it can handle the sustained discharge rate of 5Amps being pulled from it.


Thank you for responding Skater! I believe it was software the websites were talking about and it was during a move. Then when I saw the video of the face tracking demo I was wondering if the jerkyness was due to software or extremely fast servos vs the slower framerate of the webcam. Idk, like I said Im kinda new to this. As far as the betteries I did plan for the higher drain. It will have separate 4400maH lipo pack. Only half of the servos would probably move at the same time so i hope the draw isnt that much. I cant wait to test it out. Ive ordered 11 Aug and still awaiting replies to my inquiries. :/


The jerkiness in the wall-e video (for example) is actually due to the weight of the head and flexability of the plastic. Everytime the head rotates a bit, the weight of the head vibrates a bit and it wobbles.:)




:D Thanx dude! I have 2 robots sitting in front of me that need building. Stay tuned!

Oh, and a pretty awesome ARC package ready to be released...... drum roll


Eh ehm, did you implemented the save as on exit:)

Oeh now i'm very .... tell me tell me:)

when do you release ??? ;)


Yes, save on exit is done:)

I'm having some reliability issues with the Sound Script Automation Control. I may release ARC tonight with a bunch of fixes and hide the automation control if it's not ready. Check back in 9-10 hours