🚀 go-pugleaf

In article <chrisp.715431369@narbelek> chrisp@cs.uwa.oz.au (chris pudney)
writes:
>
>G'day,
>
>Consider a mechanism with three orthogonal joint axes coincident at a single
>point, that is, a spherical wrist with roll, pitch and yaw motion axes.  How
>can this mechanism be represented using D-H parameters.  I can't come up
>with a solution.  Can you?  If so would you please let me know it?
>
>Chris.

In section 3.11 of Suh & Radcliffe, Kinematics and Mechanisms Design, Wiley
1978, the Hartenberg-Denavit notation is simply a 4*4 attitude/position
transformation in homogeneous coordinates. In the upper-left 3*3 submatrix,
a straightforward orthonormal attitude matrix is provided.  In earlier sec-
tions of this chapter, the standard Cardanic angles are related to this
attitude matrix.  Alternatively, one can use the `vector components' of an
attitude vector which are truely orthogonal w.r.t. each other, but not
generally physically realisable.  See a manuscript in LaTeX retrievable via
anonymous ftp as attjob.tex in subdirectory /pub/biomch-l at ftp.nici.kun.nl.
 
Herman J. Woltring, Eindhoven/NL
woltring@nici.kun.nl (do not send private notes to the BBS address)
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