Dear Jason,
Just read you latest addition about vectors and reference frames.
Small question:
In order to rotate a frame relative to another one, you use these terms
*A.orient_axis(N, ..)*
*A.orient_body_fixed(N, …)*
I assume, these are the new versions for
A.orientnew(N, ‚Axis‘, …)
A.orientnew(N
Dear Jason,
As to the speed of the new terms, I simply tried it, using the equations of
motion of a one body pendulum.
There is no difference to the older terms:
with the *body* version the the rhs has 863, 824 operations.
with the axis version, 2 intermediate frames, the rhs has 43,722 operation
For the people developing and maintaining the mechanics modules, you may
want to look at the following book which treats mechanics problems with
some new methods. Describing rotations is greatly simplified -
https://link.springer.com/book/10.1007/0-306-47122-1
On 2/14/22 12:40 PM, Peter Stahl
Peter,
If orient_body_fixed produces longer equations of motion than chaining
orient_axis (or the older orient() and orientnew()), then we should figure
out what the problem is with orient_body_fixed. orient_body_fixed should
produce shorter equations of motion because the angular velocities are
Alan,
Thanks for the tip. There are lots of mechanics notations and methods, but
I'm not sure I'd use many of them for teaching mechanics because the more
advanced math principles often hide the forest for the trees for
engineering students. These newer methods based on Geometric and Clifford
alge
Peter,
I opened this issue: https://github.com/sympy/sympy/issues/23075
Jason
moorepants.info
+01 530-601-9791
On Mon, Feb 14, 2022 at 7:28 PM Jason Moore wrote:
> Peter,
>
> If orient_body_fixed produces longer equations of motion than chaining
> orient_axis (or the older orient() and orient
Dear Alan,
Thanks a lot for the hint!
I had a look at the book in Amazon, what little they let me see.
I must admit that books not written in the format
- some motivation
- definition
- theorem
- proof
are difficult for me to read. I get lost in the narrative.
Take care! Peter
On Mon 14. Feb 2022
