dividing angle in complex posture in standing mode

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1

Dear All
I am using Standing-Model for validate it for complex postures.
I am using this model with changing in its constraints.
I designed and fabricated new 3Axial device for measuring Isometric
(static) moments about L5/S1 or any level.
(ISB2007-Journal of Biomechanics, Volume 40, Supplement 2, 2007, Page
S155.
I have some question about it:

1-When we want model to be flex/Extension-L.B or rotation . I use
“Mannequin.any” and change angle of Thorax depend on Pelvis, What are
angles of L5,L4,L3,L2,L1?

2- For find MVC of model(in up right position) I exert increasing load
like Prof. DeZee (Journal of Biomechanics 40 (2007) 1219–1227) and
could get results similar to him, but I did it (increasing load- or
loop) manual step by step and check while MuxMuscleActivity be 100%.
Can we do it with “Do” or “For” or “Loop” command like FORTRAN, ANSYS
, Matlab and so on?

3-If we want find MVC in Flex. position like (30’Flextion):
A-Our moment arm is different from Up-right position,
What do we do for finding this moment ?

      B-When we exert load and use "Mannequin.any":

                  AnyFolder Load = {
               AnyVec3 TopVertebra = {396.0, 0.000, 0.000};
                 .
                 .
                 .
                 };
   What is coordinate of it? (I mean local or global)
   (I mean, when we want exert this load when model is flexed.
   What is direction of it? ,Is it vertical to that segment?
2

Hi,

> 1-When we want model to be flex/Extension-L.B or rotation.
> I use “Mannequin.any” and change angle of Thorax depend
> on Pelvis, What are
> angles of L5,L4,L3,L2,L1?

They are being set automatically in the model depending on the user-
specified angle between the thorax and the pelvis. This is what we
call the spinal rhythm. You can find the definition in the
JointsAndDrivers file. It basically makes the spine deform like an
elastic beam.

> 2- For find MVC of model(in up right position) I exert
> increasing load like Prof. DeZee (Journal of
> Biomechanics 40 (2007) 1219–1227) and
> could get results similar to him, but I did it
> (increasing load- or loop) manual step by step
> and check while MuxMuscleActivity be 100%.
> Can we do it with “Do” or “For” or “Loop” command
> like FORTRAN, ANSYS, Matlab and so on?

Yes, it is very simple, really. You just do the following:

  1. In the study section, make sure that tEnd = 1 and nStep > 1, for
    instance nStep = 10 or such.

  2. Simply make the load you apply depend on time by multiplying it
    with t. The variable t exists in all objects. When time rund from 0
    to tEnd, your applied load will increase from 0 to whatever value you
    want. You will then get a number of computation steps with increasing
    load when you run the inverse dynamic analysis.

> 3-If we want find MVC in Flex. position like (30’Flextion):
> A-Our moment arm is different from Up-right position,
> What do we do for finding this moment ?

You can create a rotational measure between the pelvis and the thorax
and then apply the external load as an AnyForce directly to this
measure. An AnyForce applied to a rotational measure becomes a
moment, which will be exactly what you specify and independent of the
posture. Look here for details:
http://www.anybodytech.com/662.0.html

> B-When we exert load and use “Mannequin.any”:
>
> AnyFolder Load = {
> AnyVec3 TopVertebra = {396.0, 0.000, 0.000};
> .
> .
> .
> };
> What is coordinate of it? (I mean local or global)
> (I mean, when we want exert this load when model is flexed.
> What is direction of it? ,Is it vertical to that segment?

The loads defined in the mannequin file are in global coordinates, so
their directions are independent of the posture. You can find the
precise application point of each force by tracking the name of the
variable in the JointsAndDrivers file.

Best regards,
John

3

Dear Dr John Rasmussen

Thanks so much about your quick answering, But let me ask another
questions:

1- I could not find definition of Thorax-Pelvic angle in between of
L1, L2,L3,L4,L5,… in JointsAndDrivers file.
May be your purpose is this part:

//Thorax pelvis rotation driver
AnyKinEqSimpleDriver PostureDriver ={
.
.
.
Reaction.Type = {Off,Off,Off};
};
But I do not understand of it.(how much angle are there for any Seg?)

2-I want to simulate exertion of subject in my device in AnyBody, for
this reason, It is very good and near to real state that I exert Force
than exerting moment directly to Thorax.
Can I exert “Vertical Force” to Seg with multiply of Force(in global
Ref. Frame) with Axes of Seg?
(In this way, we can exert Force vertical to Seg. in any Posture)
Please explain it.

Thanks so much.
Mahmood Reza Azghani

— In anyscript@yahoogroups.com, “AnyBody Support” <support@…> wrote:
>
> Hi,
>
> > 1-When we want model to be flex/Extension-L.B or rotation.
> > I use “Mannequin.any” and change angle of Thorax depend
> > on Pelvis, What are
> > angles of L5,L4,L3,L2,L1?
>
> They are being set automatically in the model depending on the user-
> specified angle between the thorax and the pelvis. This is what we
> call the spinal rhythm. You can find the definition in the
> JointsAndDrivers file. It basically makes the spine deform like an
> elastic beam.
>
> > 2- For find MVC of model(in up right position) I exert
> > increasing load like Prof. DeZee (Journal of
> > Biomechanics 40 (2007) 1219–1227) and
> > could get results similar to him, but I did it
> > (increasing load- or loop) manual step by step
> > and check while MuxMuscleActivity be 100%.
> > Can we do it with “Do” or “For” or “Loop” command
> > like FORTRAN, ANSYS, Matlab and so on?
>
> Yes, it is very simple, really. You just do the following:
>
> 1. In the study section, make sure that tEnd = 1 and nStep > 1, for
> instance nStep = 10 or such.
>
> 2. Simply make the load you apply depend on time by multiplying it
> with t. The variable t exists in all objects. When time rund from 0
> to tEnd, your applied load will increase from 0 to whatever value you
> want. You will then get a number of computation steps with increasing
> load when you run the inverse dynamic analysis.
>
> > 3-If we want find MVC in Flex. position like (30’Flextion):
> > A-Our moment arm is different from Up-right position,
> > What do we do for finding this moment ?
>
> You can create a rotational measure between the pelvis and the thorax
> and then apply the external load as an AnyForce directly to this
> measure. An AnyForce applied to a rotational measure becomes a
> moment, which will be exactly what you specify and independent of the
> posture. Look here for details:
> http://www.anybodytech.com/662.0.html
>
> > B-When we exert load and use “Mannequin.any”:
> >
> > AnyFolder Load = {
> > AnyVec3 TopVertebra = {396.0, 0.000, 0.000};
> > .
> > .
> > .
> > };
> > What is coordinate of it? (I mean local or global)
> > (I mean, when we want exert this load when model is flexed.
> > What is direction of it? ,Is it vertical to that segment?
>
> The loads defined in the mannequin file are in global coordinates, so
> their directions are independent of the posture. You can find the
> precise application point of each force by tracking the name of the
> variable in the JointsAndDrivers file.
>
> Best regards,
> John
>

4

> 1- I could not find definition of Thorax-Pelvic angle
> in between of L1, L2,L3,L4,L5,… in JointsAndDrivers
> file.
> May be your purpose is this part:
>
> //Thorax pelvis rotation driver
> AnyKinEqSimpleDriver PostureDriver ={
> .
> .
> .
> Reaction.Type = {Off,Off,Off};
> };
> But I do not understand of it.(how much angle are
> there for any Seg?)

This is very simple. The angle in each vertebral joint can be found
when you look the joint up in the tree view. Try, for instance, to
navigate you way through the tree to this variable after having
executed the kinematic analysis:
Main.Model.HumanModel.Trunk.JointsLumbar.L4L5Jnt.Pos
The variable contains the three angles of the spherical joint between
L4 and L5.

> 2-I want to simulate exertion of subject in my
> device in AnyBody, for this reason, It is very
> good and near to real state that I exert Force
> than exerting moment directly to Thorax.
> Can I exert “Vertical Force” to Seg with multiply
> of Force(in global Ref. Frame) with Axes of Seg?

It is much simpler to do. Just attach an AnyForce3D to the point
where you want to apply a force and specify the force vector in
global coordinates in the property F in the AnyForce3D object.

Best regards,
John