By: Nobody/Anonymous - nobody
file Quaternion to Euler Angles slight correction
2006年02月24日 07:14
Hello,
First, congratulations
on your excellent 3D maths site! It's been really useful, thanks a
lot =)
Now, on this page: https://www.euclideanspace.com/maths/geometry/rotations/conversions/quaternionToEuler/index.htm
When
you consider the singularity at attitude -90 degrees, you
ask:
" have I made an error here? in the
examples it seems to require: heading = -2 * atan2(x,w)
"
Actually, there is a problem with the
atan2 arguments. Here:
"
w = -z =
0.7071(c(1-3))
-x = y = 0.7071(s(1-3))
(...)
w
= -z = 0.7071(cos((heading-bank)/2))
x = -y =
0.7071(sin((heading-bank)/2)) <--
error
(...)
heading-bank = 2
* atan2(x,w) <-- resulting error
"
The
marked line should read "-x = y =
0.7071(sin((heading-bank)/2))", resulting in
"heading-bank = 2 *
atan2(-x,w)"
or
"heading-bank = 2 *
atan2(y,w)" <-- would be nice to change both
(heading+bank) and (heading-bank) expressions to this
one
Should work fine then!
Vitor
Barata
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