Re: Coordinate system

Mei-Chu Cheung ([email protected])
Sun, 21 May 1995 14:55:45 -0700 (PDT)


I also was interested in what the coordinate system
would be. I looked through the spec. and the earlier
posts and didn't seem to see a consensus, so I will
enter a thought or two. First, definitely not a left
handed coordinate system, reason being that so much
engineering is based on the rhs including everything
from the direction of electricity flow and their force
fields to vector math. This is the type of coordinate
system people will probably find later on when we have
enough bandwidth for real simulation and they start
referring to the physics and advanced simulation books.

Another thought is what orientation should the coordinate
system be in. I realize why people like the X-right, Y-up,
with Z perpendicular to the screen, mostly because they are
used to seeing this on graph paper and it extends very nicely
to the screen. I think that we need to make a paradigm
shift when we go into 3-d, and rather than making the global
cartesian system conform to the 2-d stuff we have been using,
something intuitive to the 3-d world would be appropriate.
My feeling on what may be more explainable to the average
person coming into 3-d is X-forward, Z-up, now using the
right hand rule we can say Y is to the left. The reason
this makes sense to me is I can look at the ground I am
travelling over in the 2-d sense of x-y and add the height
with z. Just some thoughts.

Brett Weichers
[email protected]
Dynamics consulting available.
(Flight, Ground Vehicles, or Mechanisms)