Re: I'm Walkin' here!!

["David Krentz" <david_krentz@fa.disney.com>]

Reply to:RE>>I'm Walkin' here!!                              11:55 AM
6/12/98

 Betty Cunningham wrote;

If you design your armature so that your critter has his feet directly
under his shoulders but his elbows turned out and slightly bent, I think
you will find a little more leeway than what a pig, camel, or elephant
can do.  These all walk with a limb path with the limbs constantly under
the body.  The limbs of a quadraped dinosaur would seem to swing OUT
during each reach forwards (rather like the chameleon already being
discussed).

  The creature in question does possess the semi-sprawl you refer to, as well
as a minimal amount of fore and aft movement in the scapulas, but still, a
rotary walk is difficult to accomplish.  I mentioned a pig simply because of
it's generalized body type body type, that's all.  I guess the best way to
describe what I mean is this.  If I had a dining room table with long legs
that was doing a camel walk across the room, it could tranfer it's weight to
one side of it's "body" and balance itself while the legs on the other side
were both suspended in mid air and swinging forward.  Now say I have a dining
room table with really short legs that is attempting the camel walk.  It
would really have to lean the side to maintian its balance as the legs on the
opposite side passed under the body.  Hope that makes sense!

  David Krentz
--------------------------------------
Date: 6/12/98 11:27 AM
To: David Krentz
From: bettyc@flyinggoat.com
the list has been recently discussing shoulder girdle configurations.

 If you design your armature so that your critter has his feet directly
under his shoulders but his elbows turned out and slightly bent, I think
you will find a little more leeway than what a pig, camel, or elephant
can do.  These all walk with a limb path with the limbs constantly under
the body.  The limbs of a quadraped dinosaur would seem to swing OUT
during each reach forwards (rather like the chameleon already being
discussed).  I believe this would also give you a bit more vertical bob
and a rollicking roll of the front-end each step than what a pig, etc,
does (you could possibly get some nice character-building head swings
during a walk)

Myself, esthetically, I'd want to keep this swing-out to a minimum-just
hinting at it- as the conventional public would see it as a return to
the lets-stick-fins-on-an-iguana-and-call-it-a-dinosaur SF effect days.

-Betty Cunningham
illustrator, animator, and still likes to collect dead things

David Krentz wrote:
>
> Subject: I'm Walkin' here!!                                  7:40 AM
> 6/12/98
>
>   Is there any theories on quadruped locomotion regarding the benefits of a
> rotary (camel walk) gait vs. a transverse walk?  In my observations, it
> appears that "taller" animals seem to snap into the rotary walk More often
> than shorter ones.  When I say taller animals, I mean giraffes, elephants
and
> specifically camels.  Maybe this has to do with shifting the balance to one
> side of the body while the long legs on the other side are both in a
> suspended phase.  I'm trying to imagine an ankylosaur in a rotary walk, but
> from test animation, the poor creature would tip over very quickly due to
> it's wide body base and short little legs.  It  makes sense to me that it
> would walk like a big fat pig.  Sauropods on the other hand, with similar
> limbs to elephants( I realize I'm  being very biased here ) may really have
> benefited from a rotary walk because of their great height, using their
necks
> and tails as balancing tools as it leaned off centre.  Is there a way to
tell
> what form of locomotion a dinosaur used from trackways?
>   I don't want to sound condescending, but for those who have no clue what
I
> mean I'll clarify the difference between the two types of walk as it may be
> beneficial to artists.
>
>   Transverse:  One side is stretched out; hind limb back, front limb
forward,
>  and the other side is squashed;  hind limb forward ( planting just behind
> where the front foot was) and the front limb is back.  The great majority
of
> animals walk like this.  Cats, dogs, crawling babies...
>    Rotary:  One side the legs are both forward and on the other side they
are
> both back.  Camels walk almost exclusively in this manor, and elephants
snap
> into it every now and then.
>
>   David Krentz,
> Walt Disney Feature Animation