[Avery Andrews 931026.0851]
nu14:
Would anyone be interested in a cleaned-up version of my `nu14'
program, a modification of Bill Powers' `14deg'. What it does
is illustrate how 2nd order control systems (as in the Marken
spreadsheet) can do something in a realistic world, such as
maintain a constant hand orientation as an arm moves around.
No deep conceptual points here, but maybe a useful illustration?
It's a PC program (EGA/VGA, mouse required). Also, would there
be any interest in a Unix/X-Windows version? (I think it might
be a step on the way to more ambitious Unix/X programs, like a
version of Little Man).
pointing in BBS:
On a completely different tack, I'm quite puzzled by the aim of
Bill Powers' commentary on Soechting et al in last years BBS.
They were trying to show that the brain computes a transformation
from head-centered to shoulder-centered coordinates (an idea that
pleases me, since I noticed in the course of the Cartesian Blues
affair that this might be a useful thing to do). They tried to
do this with a pointing task involving rather unusual conditions,
and Bill criticised them for having a wrong model of pointing. I
find this inappropriate, since they weren't trying to explain pointing
under ordinary conditions, but to use facts about pointing under odd
conditions to make a point.
Avery.Andrews@anu.edu.au