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 Robotics / 19490
19489  |  19491
Subject: 
Re: articulation points?
Newsgroups: 
lugnet.build.mecha, lugnet.technic, lugnet.robotics
Date: 
Wed, 20 Nov 2002 08:19:09 GMT
Viewed: 
249 times
  
Not to be a goof, but, OMG! Bram is Crazy Smart! I gotta go a take some more
vitamins and drink Carrot Juice! Ahhh!

I see the concept much the same, I figure if we refer to a POA in a Mecha model
as the counting scheme, we won't get alot of run away numbers. Or at least
on the gloss description you could say:

"Ehhh my Mech moves here in this spot (POA)
and it has 3 different DOF inherent to the design." (in that POA)

I Submit this for thought. Bryce taught me this Double up Ball Joint Technique:
http://www.brickshelf.com/cgi-bin/gallery.cgi?i=240763
Look at the Ankles Hips and Shoulders.
Note the Turn Swivel of the Left Foot at the Ankel.

He evan uses three stacked on thier sides in some of his Models.

What's interesting is that by itself, one Ball Joints has 3 DOF. (right?)
So when you add two side by side, and bind them together, they start to
restrict themselves at the upper most rotation because they physically
collide with one another, yet the rotation characteristics become not only
stronger but for lack of a beautiful description, start to turn in a really
weird way. Like a blending of angles as they bend.

So using the terms for the sake of argument, The POA loses DOF but gain
reliability in the robust design. Where it seems the lost DOF transmutes
itself into strength.

Try it, put two ball joints together, it's twice of strong of course, but
then start twisting the set to the side and the fiction is impressive. A
cause of the angles no doubt.

Ok McGlone 101 done.

e



Message is in Reply To:
  RE: articulation points?
 
(...) However, a device is made up of several objects. Each component, if treated separately, has six degrees of freedom. Thus each component of, for example, the human arm (reduced to an upper arm, lower arm, and hand) has 6 DOF, for a total of 18. (...) (22 years ago, 20-Nov-02, to lugnet.build.mecha, lugnet.technic, lugnet.robotics)

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