View Full Version : Limb length

10-22-2010, 01:01 PM
I'm curious as to why, with the quads that's I've seen, that their legs all tend to be relatively short?

I would think that with a longer length of leg that a quad, at least, would be able to traverse much more quickly. I realize that at some point the weight and torque requirements of an extended limb length would be counter-productive, but I would think that roughly three or four servo-body lengths per limb segment would be reasonable - they seem to run around two servo lengths from what I can tell. Obviously, with bots such as Giger, there are exceptions to what I've observed so far, but generally speaking that seems to be the case.


10-22-2010, 01:08 PM
The torque requirements for servos goes up quickly as legs get longer (or bodies get wider/longer). This is particularly important for AX-12s, because although they may handle the torque requirement, they have issues handling it for a long time -- and thus they overheat quicker with longer legs.


10-22-2010, 01:26 PM
Thanks for the timely reply lnxfergy, much appreciated. :)

02-09-2011, 01:14 AM
Inxfergy - You make an interesting point. Do the AX-12+ tend to loose power/torque as they heat up? I wonder if I should add a time variable to my data I plan to collect (Current draw vs. Torque) So maybe I need to do an additional set, Current Draw vs. Time @ set torque values?

I am also curious if the current draw changes over sweep of angles, but I can't figure out how to hold the torque constant so I probably wont do that one.