I am outputting segment axes and muscle points from my model and
would like to confirm their format.
Am I correct to assume that the locations of the axes are with
respect to the global coordinate system?
Are the outputted axes information the direction cosines between
the global and the local (segment) coordinate systems? Thus, could
the outputted axes information be formatted as:
1: Yes this is correct the “Axes” property always referes to the
global ref system. The “ARel” property on the other hand is wrt. the
local coordinate system.
2: Yes this description seems ok
3: The “sRel” values of a AnyRefNode, which are used by the muscles
are always given in the reference system of the segment they belong
to. If you look at the “r” property of the nodes you will get the
nodes position vector wrt. to the global ref system.
Best regards
Søren, AnyBody Support
— In anyscript@yahoogroups.com, “chrisjgatti” <cjgatti@…> wrote:
>
> I am outputting segment axes and muscle points from my model and
> would like to confirm their format.
>
> 1) Am I correct to assume that the locations of the axes are with
> respect to the global coordinate system?
>
> 2) Are the outputted axes information the direction cosines
between
> the global and the local (segment) coordinate systems? Thus, could
> the outputted axes information be formatted as:
>
> [Axes[0][0], Axes[0][1], Axes[0][2];
> Axes[1][0], Axes[1][1], Axes[1][2];
> Axes[2][0], Axes[2][1], Axes[2][2]]
>
> which would correspond to the rotation matrix:
>
> [cosXx, cosXy, cosXz;
> cosYx, cosYy, cosYz;
> cosZx, coxZy, cosZz]
>
> (where cosXy would be the direction cosine between the global x-
axis
> (X…capital letter) and the local y-axis (y…lowercase letter))?
>
> 3) Are the muscle point locations output in the segment (local)
> coordinate sytstems to which they are associated with in the .any
> files?
>
> Thanks for the help.
>
> Chris
>
Thanks a lot. I assume you can output all the muscle via points too
(if a muscle has via points), and not just the origin and insertion
points?
What I am really interested in, is the muscle lines of action. For
some muscles in some postures, the line of action from the origin to
the insertion is an acceptable assumption, but for others, which
wrap around objects, the origin-insertion line isn’t quite accurate.
Is there any easy output available for this? If this cannot be done
directly, can you output the points which contact the wrapping
object, so that a line of action from the origin to the wrapping
point can be determined?
Thanks again.
Chris
— In anyscript@yahoogroups.com, “AnyBody Support” <support@…>
wrote:
>
> Hi Chris
>
> Here are some answers to your questions.
>
> 1: Yes this is correct the “Axes” property always referes to the
> global ref system. The “ARel” property on the other hand is wrt.
the
> local coordinate system.
>
> 2: Yes this description seems ok
>
> 3: The “sRel” values of a AnyRefNode, which are used by the
muscles
> are always given in the reference system of the segment they
belong
> to. If you look at the “r” property of the nodes you will get the
> nodes position vector wrt. to the global ref system.
>
> Best regards
> Søren, AnyBody Support
>
>
>
> — In anyscript@yahoogroups.com, “chrisjgatti” <cjgatti@> wrote:
> >
> > I am outputting segment axes and muscle points from my model and
> > would like to confirm their format.
> >
> > 1) Am I correct to assume that the locations of the axes are
with
> > respect to the global coordinate system?
> >
> > 2) Are the outputted axes information the direction cosines
> between
> > the global and the local (segment) coordinate systems? Thus,
could
> > the outputted axes information be formatted as:
> >
> > [Axes[0][0], Axes[0][1], Axes[0][2];
> > Axes[1][0], Axes[1][1], Axes[1][2];
> > Axes[2][0], Axes[2][1], Axes[2][2]]
> >
> > which would correspond to the rotation matrix:
> >
> > [cosXx, cosXy, cosXz;
> > cosYx, cosYy, cosYz;
> > cosZx, coxZy, cosZz]
> >
> > (where cosXy would be the direction cosine between the global x-
> axis
> > (X…capital letter) and the local y-axis (y…lowercase
letter))?
> >
> > 3) Are the muscle point locations output in the segment (local)
> > coordinate sytstems to which they are associated with in
the .any
> > files?
> >
> > Thanks for the help.
> >
> > Chris
> >
>
Yes the viapoints can be outputted just as any other point.
The contact points in the wrapping muscles can not be save in any
way, so this is simply not possible today to get coordinates of
these points out, i am sorry.
Could you explain a little bit more about what to use this for?,
this will help us get an idea on what the user need and possible
improve the next version. We are always open for suggestions on
future facilites.
Best regards
Søren, AnyBody Support
— In anyscript@yahoogroups.com, “chrisjgatti” <cjgatti@…> wrote:
>
> Søren,
>
> Thanks a lot. I assume you can output all the muscle via points
too
> (if a muscle has via points), and not just the origin and
insertion
> points?
>
> What I am really interested in, is the muscle lines of action. For
> some muscles in some postures, the line of action from the origin
to
> the insertion is an acceptable assumption, but for others, which
> wrap around objects, the origin-insertion line isn’t quite
accurate.
> Is there any easy output available for this? If this cannot be
done
> directly, can you output the points which contact the wrapping
> object, so that a line of action from the origin to the wrapping
> point can be determined?
>
> Thanks again.
>
> Chris
>
> — In anyscript@yahoogroups.com, “AnyBody Support” <support@>
> wrote:
> >
> > Hi Chris
> >
> > Here are some answers to your questions.
> >
> > 1: Yes this is correct the “Axes” property always referes to the
> > global ref system. The “ARel” property on the other hand is wrt.
> the
> > local coordinate system.
> >
> > 2: Yes this description seems ok
> >
> > 3: The “sRel” values of a AnyRefNode, which are used by the
> muscles
> > are always given in the reference system of the segment they
> belong
> > to. If you look at the “r” property of the nodes you will get
the
> > nodes position vector wrt. to the global ref system.
> >
> > Best regards
> > Søren, AnyBody Support
> >
> >
> >
> > — In anyscript@yahoogroups.com, “chrisjgatti” <cjgatti@> wrote:
> > >
> > > I am outputting segment axes and muscle points from my model
and
> > > would like to confirm their format.
> > >
> > > 1) Am I correct to assume that the locations of the axes are
> with
> > > respect to the global coordinate system?
> > >
> > > 2) Are the outputted axes information the direction cosines
> > between
> > > the global and the local (segment) coordinate systems? Thus,
> could
> > > the outputted axes information be formatted as:
> > >
> > > [Axes[0][0], Axes[0][1], Axes[0][2];
> > > Axes[1][0], Axes[1][1], Axes[1][2];
> > > Axes[2][0], Axes[2][1], Axes[2][2]]
> > >
> > > which would correspond to the rotation matrix:
> > >
> > > [cosXx, cosXy, cosXz;
> > > cosYx, cosYy, cosYz;
> > > cosZx, coxZy, cosZz]
> > >
> > > (where cosXy would be the direction cosine between the global
x-
> > axis
> > > (X…capital letter) and the local y-axis (y…lowercase
> letter))?
> > >
> > > 3) Are the muscle point locations output in the segment
(local)
> > > coordinate sytstems to which they are associated with in
> the .any
> > > files?
> > >
> > > Thanks for the help.
> > >
> > > Chris
> > >
> >
>
I am interested in the muscle lines of action to use as inputs to a
finite element model of the shoulder. As I mentioned before, the
origin-insertion path works well for some muscles in some postures,
although not so well for others. For example, if the origin-
insertion method is used for the middle deltoid–with the arm in 0
degrees of abduction, flexion, and rotation–the line of action
points superiorly and medially. However, if the most medial muscle
wrap point is used with the muscle origin, the line of action points
almost completely medially. Does this help?
Chris
— In anyscript@yahoogroups.com, “AnyBody Support” <support@…>
wrote:
>
> Hi Chris
>
> Yes the viapoints can be outputted just as any other point.
>
> The contact points in the wrapping muscles can not be save in any
> way, so this is simply not possible today to get coordinates of
> these points out, i am sorry.
>
> Could you explain a little bit more about what to use this for?,
> this will help us get an idea on what the user need and possible
> improve the next version. We are always open for suggestions on
> future facilites.
>
> Best regards
> Søren, AnyBody Support
>
>
> — In anyscript@yahoogroups.com, “chrisjgatti” <cjgatti@> wrote:
> >
> > Søren,
> >
> > Thanks a lot. I assume you can output all the muscle via points
> too
> > (if a muscle has via points), and not just the origin and
> insertion
> > points?
> >
> > What I am really interested in, is the muscle lines of action.
For
> > some muscles in some postures, the line of action from the
origin
> to
> > the insertion is an acceptable assumption, but for others, which
> > wrap around objects, the origin-insertion line isn’t quite
> accurate.
> > Is there any easy output available for this? If this cannot be
> done
> > directly, can you output the points which contact the wrapping
> > object, so that a line of action from the origin to the wrapping
> > point can be determined?
> >
> > Thanks again.
> >
> > Chris
> >
> > — In anyscript@yahoogroups.com, “AnyBody Support” <support@>
> > wrote:
> > >
> > > Hi Chris
> > >
> > > Here are some answers to your questions.
> > >
> > > 1: Yes this is correct the “Axes” property always referes to
the
> > > global ref system. The “ARel” property on the other hand is
wrt.
> > the
> > > local coordinate system.
> > >
> > > 2: Yes this description seems ok
> > >
> > > 3: The “sRel” values of a AnyRefNode, which are used by the
> > muscles
> > > are always given in the reference system of the segment they
> > belong
> > > to. If you look at the “r” property of the nodes you will get
> the
> > > nodes position vector wrt. to the global ref system.
> > >
> > > Best regards
> > > Søren, AnyBody Support
> > >
> > >
> > >
> > > — In anyscript@yahoogroups.com, “chrisjgatti” <cjgatti@>
wrote:
> > > >
> > > > I am outputting segment axes and muscle points from my model
> and
> > > > would like to confirm their format.
> > > >
> > > > 1) Am I correct to assume that the locations of the axes are
> > with
> > > > respect to the global coordinate system?
> > > >
> > > > 2) Are the outputted axes information the direction cosines
> > > between
> > > > the global and the local (segment) coordinate systems? Thus,
> > could
> > > > the outputted axes information be formatted as:
> > > >
> > > > [Axes[0][0], Axes[0][1], Axes[0][2];
> > > > Axes[1][0], Axes[1][1], Axes[1][2];
> > > > Axes[2][0], Axes[2][1], Axes[2][2]]
> > > >
> > > > which would correspond to the rotation matrix:
> > > >
> > > > [cosXx, cosXy, cosXz;
> > > > cosYx, cosYy, cosYz;
> > > > cosZx, coxZy, cosZz]
> > > >
> > > > (where cosXy would be the direction cosine between the
global
> x-
> > > axis
> > > > (X…capital letter) and the local y-axis (y…lowercase
> > letter))?
> > > >
> > > > 3) Are the muscle point locations output in the segment
> (local)
> > > > coordinate sytstems to which they are associated with in
> > the .any
> > > > files?
> > > >
> > > > Thanks for the help.
> > > >
> > > > Chris
> > > >
> > >
> >
>