Standing on one leg model

[system]

Hello everybody,
I am trying to create a model that stands on one leg only. First off, I
just removed the lines, from the regular StandingModel where the left
leg is fixed to the ground, that (obviously) lead to a kinematically
indetermined system.

Second try was to combine the FreePostureMove model with the
StandingModel:

1. Use the StandingModel as a basis
2. Comment out the lines where left toe and heel are fixed to the ground
3. Copy the lines from FreePostureMove where the left leg is defined,
   to the StandingModel

Thus I was hoping that I could create a correct model however it is not
compatible: the message window gives me error messages that some
dimensions do not match. And contains too few kinematic constraints.

Has anybody tried (maybe already succeeded) to create a model that
stands on one leg only.

Advices, suggestions would be highly appreciated

Regards Sebastian

[system]

Hi Sebastian

Here is initially a short description of the drivers of the standing
model, it is driven in the following way:

For both the right and left legs:
Toe tip vertically constrainet to ground
Heel vertically constrainet to ground
Ankle position driven in global x direction

Three rotations is driven in the hip (Means no dof left in hip)
One rotation is driven in the knee (Means no dof left in knee)
Ankle eversion is driven (Means flexion is still FREE in ankle)

This is in total 8 drivers for each leg…

COM driven sideways and for/back (X,Z)

Neck is driven
3 Rotations between Pelvis and Thorax + the spine rhythm
(this means all dof on spine is driven )

Arms are also fully driven…

Summing up the driver on the left leg add up up to 8 driven dofs, by
replacing them wiht the freePostureMove drivers will add 6 drivers
to the model, so you will have 2 less than before.

If you make a small sketch of the problem i think you will see that
this is the height of the left pelvis joint. Since the hip and knee
is driven, and the foot is driven to be flat on the floor this means
the leg provides the height of the hipjoint. Instead of the height
you could also drive the rotation of the pelvis around the global x
axis.

The other one is the position of the left hip joint in the x
direction, which was previously controlled via the x position of the
foot. You could also say that it is the rotation of the pelvis around
the global Z direction.

So to make the standing model work you need to apply these two
additional drivers.

Please do hesitate to ask again if you have further questions

Best regards
Søren, AnyBody Support

— In anyscript@yahoogroups.com, “sebastian.kreissl”
<sebastian.kreissl@…> wrote:
>
> Hello everybody,
> I am trying to create a model that stands on one leg only. First
off, I
> just removed the lines, from the regular StandingModel where the
left
> leg is fixed to the ground, that (obviously) lead to a
kinematically
> indetermined system.
>
> Second try was to combine the FreePostureMove model with the
> StandingModel:
> 1. Use the StandingModel as a basis
> 2. Comment out the lines where left toe and heel are fixed to the
ground
> 3. Copy the lines from FreePostureMove where the left leg is
defined,
> to the StandingModel
>
> Thus I was hoping that I could create a correct model however it is
not
> compatible: the message window gives me error messages that some
> dimensions do not match. And contains too few kinematic constraints.
>
> Has anybody tried (maybe already succeeded) to create a model that
> stands on one leg only.
>
> Advices, suggestions would be highly appreciated
>
> Regards Sebastian
>

[system]

Hello Søren,
thanks for your fast reply!
Just to repeat: I removed the constraint that fixes the left toe
(1DOF) and the left heel (1DOF) as well as the constraint that the
left ankle is above the z-axis (1DOF). Isnt that three DOFs (Position
of foot in x- and y-direction as well as the rotation of the foot)
less?

As you suggested I added one driver for the x-position of the hip (on
the
node “Main.Model.HumanModel.Trunk.SegmentsLumbar.PelvisSeg.HipJointLef
t”) and one driver for the y-postion of the hip (on the same node).

I can compile the model without error messages, but when trying to
run the kinematic analysis I get the message: “… analysis failed :
230 independent constraints and 231 unknowns” so something is still
redundent.

Thanks in advance
Sebastian

— In anyscript@yahoogroups.com, “AnyBody Support” <support@…>
wrote:
>
> Hi Sebastian
>
> Here is initially a short description of the drivers of the
standing
> model, it is driven in the following way:
>
> For both the right and left legs:
> Toe tip vertically constrainet to ground
> Heel vertically constrainet to ground
> Ankle position driven in global x direction
>
> Three rotations is driven in the hip (Means no dof left in hip)
> One rotation is driven in the knee (Means no dof left in knee)
> Ankle eversion is driven (Means flexion is still FREE in ankle)
>
> This is in total 8 drivers for each leg…
>
> COM driven sideways and for/back (X,Z)
>
>
>
> Neck is driven
> 3 Rotations between Pelvis and Thorax + the spine rhythm
> (this means all dof on spine is driven )
>
> Arms are also fully driven…
>
>
> Summing up the driver on the left leg add up up to 8 driven dofs,
by
> replacing them wiht the freePostureMove drivers will add 6 drivers
> to the model, so you will have 2 less than before.
>
> If you make a small sketch of the problem i think you will see that
> this is the height of the left pelvis joint. Since the hip and knee
> is driven, and the foot is driven to be flat on the floor this
means
> the leg provides the height of the hipjoint. Instead of the height
> you could also drive the rotation of the pelvis around the global x
> axis.
>
> The other one is the position of the left hip joint in the x
> direction, which was previously controlled via the x position of
the
> foot. You could also say that it is the rotation of the pelvis
around
> the global Z direction.
>
> So to make the standing model work you need to apply these two
> additional drivers.
>
> Please do hesitate to ask again if you have further questions
>
> Best regards
> Søren, AnyBody Support
>
>
> — In anyscript@yahoogroups.com, “sebastian.kreissl”
> <sebastian.kreissl@> wrote:
> >
> > Hello everybody,
> > I am trying to create a model that stands on one leg only. First
> off, I
> > just removed the lines, from the regular StandingModel where the
> left
> > leg is fixed to the ground, that (obviously) lead to a
> kinematically
> > indetermined system.
> >
> > Second try was to combine the FreePostureMove model with the
> > StandingModel:
> > 1. Use the StandingModel as a basis
> > 2. Comment out the lines where left toe and heel are fixed to the
> ground
> > 3. Copy the lines from FreePostureMove where the left leg is
> defined,
> > to the StandingModel
> >
> > Thus I was hoping that I could create a correct model however it
is
> not
> > compatible: the message window gives me error messages that some
> > dimensions do not match. And contains too few kinematic
constraints.
> >
> > Has anybody tried (maybe already succeeded) to create a model
that
> > stands on one leg only.
> >
> > Advices, suggestions would be highly appreciated
> >
> > Regards Sebastian
> >
>

[system]

Hi Sebastian

I have looked at my skecth of your model again, and i can not see
what should be wrong

It is correct that you remove three drivers on the left foot, but you
have also added three drivers?

These three are:
1 Flexion of the ankle (this should come if you have applied the
drivers from the freeposture model)
2 The hip left x direction
3 the hip left height

Are you sure that when you added the leg drivers from the free
posture model to the left leg, you have deleted both the hip, knee,
and ankle drivers originally in the standingmodel? It could be one of
those you have twice?

If it continues to cause problems please upload the Arep part of the
model to the file section of the group and we will have a look it.

Best regards
Søren, AnyBody Support

— In anyscript@yahoogroups.com, “sebastian.kreissl”
<sebastian.kreissl@…> wrote:
>
> Hello Søren,
> thanks for your fast reply!
> Just to repeat: I removed the constraint that fixes the left toe
> (1DOF) and the left heel (1DOF) as well as the constraint that the
> left ankle is above the z-axis (1DOF). Isnt that three DOFs
(Position
> of foot in x- and y-direction as well as the rotation of the foot)
> less?
>
> As you suggested I added one driver for the x-position of the hip
(on
> the
>
node “Main.Model.HumanModel.Trunk.SegmentsLumbar.PelvisSeg.HipJointLef
> t”) and one driver for the y-postion of the hip (on the same node).
>
> I can compile the model without error messages, but when trying to
> run the kinematic analysis I get the message: “… analysis
failed :
> 230 independent constraints and 231 unknowns” so something is still
> redundent.
>
> Thanks in advance
> Sebastian
>
>
>
> — In anyscript@yahoogroups.com, “AnyBody Support” <support@>
> wrote:
> >
> > Hi Sebastian
> >
> > Here is initially a short description of the drivers of the
> standing
> > model, it is driven in the following way:
> >
> > For both the right and left legs:
> > Toe tip vertically constrainet to ground
> > Heel vertically constrainet to ground
> > Ankle position driven in global x direction
> >
> > Three rotations is driven in the hip (Means no dof left in hip)
> > One rotation is driven in the knee (Means no dof left in knee)
> > Ankle eversion is driven (Means flexion is still FREE in ankle)
> >
> > This is in total 8 drivers for each leg…
> >
> > COM driven sideways and for/back (X,Z)
> >
> >
> >
> > Neck is driven
> > 3 Rotations between Pelvis and Thorax + the spine rhythm
> > (this means all dof on spine is driven )
> >
> > Arms are also fully driven…
> >
> >
> > Summing up the driver on the left leg add up up to 8 driven dofs,
> by
> > replacing them wiht the freePostureMove drivers will add 6
drivers
> > to the model, so you will have 2 less than before.
> >
> > If you make a small sketch of the problem i think you will see
that
> > this is the height of the left pelvis joint. Since the hip and
knee
> > is driven, and the foot is driven to be flat on the floor this
> means
> > the leg provides the height of the hipjoint. Instead of the
height
> > you could also drive the rotation of the pelvis around the global
x
> > axis.
> >
> > The other one is the position of the left hip joint in the x
> > direction, which was previously controlled via the x position of
> the
> > foot. You could also say that it is the rotation of the pelvis
> around
> > the global Z direction.
> >
> > So to make the standing model work you need to apply these two
> > additional drivers.
> >
> > Please do hesitate to ask again if you have further questions
> >
> > Best regards
> > Søren, AnyBody Support
> >
> >
> > — In anyscript@yahoogroups.com, “sebastian.kreissl”
> > <sebastian.kreissl@> wrote:
> > >
> > > Hello everybody,
> > > I am trying to create a model that stands on one leg only.
First
> > off, I
> > > just removed the lines, from the regular StandingModel where
the
> > left
> > > leg is fixed to the ground, that (obviously) lead to a
> > kinematically
> > > indetermined system.
> > >
> > > Second try was to combine the FreePostureMove model with the
> > > StandingModel:
> > > 1. Use the StandingModel as a basis
> > > 2. Comment out the lines where left toe and heel are fixed to
the
> > ground
> > > 3. Copy the lines from FreePostureMove where the left leg is
> > defined,
> > > to the StandingModel
> > >
> > > Thus I was hoping that I could create a correct model however
it
> is
> > not
> > > compatible: the message window gives me error messages that
some
> > > dimensions do not match. And contains too few kinematic
> constraints.
> > >
> > > Has anybody tried (maybe already succeeded) to create a model
> that
> > > stands on one leg only.
> > >
> > > Advices, suggestions would be highly appreciated
> > >
> > > Regards Sebastian
> > >
> >
>

[system]

Hi Søren,
I think I got the kinematics now.
I as soon as the InverseDynamic analysis is working properly I will
upload the model!

Thanks again
Sebastian

— In anyscript@yahoogroups.com, “AnyBody Support” <support@…>
wrote:
>
> Hi Sebastian
>
> I have looked at my skecth of your model again, and i can not see
> what should be wrong
>
> It is correct that you remove three drivers on the left foot, but
you
> have also added three drivers?
>
> These three are:
> 1 Flexion of the ankle (this should come if you have applied the
> drivers from the freeposture model)
> 2 The hip left x direction
> 3 the hip left height
>
> Are you sure that when you added the leg drivers from the free
> posture model to the left leg, you have deleted both the hip, knee,
> and ankle drivers originally in the standingmodel? It could be one
of
> those you have twice?
>
> If it continues to cause problems please upload the Arep part of
the
> model to the file section of the group and we will have a look it.
>
> Best regards
> Søren, AnyBody Support
>
> — In anyscript@yahoogroups.com, “sebastian.kreissl”
> <sebastian.kreissl@> wrote:
> >
> > Hello Søren,
> > thanks for your fast reply!
> > Just to repeat: I removed the constraint that fixes the left toe
> > (1DOF) and the left heel (1DOF) as well as the constraint that
the
> > left ankle is above the z-axis (1DOF). Isnt that three DOFs
> (Position
> > of foot in x- and y-direction as well as the rotation of the
foot)
> > less?
> >
> > As you suggested I added one driver for the x-position of the hip
> (on
> > the
> >
>
node “Main.Model.HumanModel.Trunk.SegmentsLumbar.PelvisSeg.HipJointLef
> > t”) and one driver for the y-postion of the hip (on the same
node).
> >
> > I can compile the model without error messages, but when trying
to
> > run the kinematic analysis I get the message: “… analysis
> failed :
> > 230 independent constraints and 231 unknowns” so something is
still
> > redundent.
> >
> > Thanks in advance
> > Sebastian
> >
> >
> >
> > — In anyscript@yahoogroups.com, “AnyBody Support” <support@>
> > wrote:
> > >
> > > Hi Sebastian
> > >
> > > Here is initially a short description of the drivers of the
> > standing
> > > model, it is driven in the following way:
> > >
> > > For both the right and left legs:
> > > Toe tip vertically constrainet to ground
> > > Heel vertically constrainet to ground
> > > Ankle position driven in global x direction
> > >
> > > Three rotations is driven in the hip (Means no dof left in
hip)
> > > One rotation is driven in the knee (Means no dof left in knee)
> > > Ankle eversion is driven (Means flexion is still FREE in ankle)
> > >
> > > This is in total 8 drivers for each leg…
> > >
> > > COM driven sideways and for/back (X,Z)
> > >
> > >
> > >
> > > Neck is driven
> > > 3 Rotations between Pelvis and Thorax + the spine rhythm
> > > (this means all dof on spine is driven )
> > >
> > > Arms are also fully driven…
> > >
> > >
> > > Summing up the driver on the left leg add up up to 8 driven
dofs,
> > by
> > > replacing them wiht the freePostureMove drivers will add 6
> drivers
> > > to the model, so you will have 2 less than before.
> > >
> > > If you make a small sketch of the problem i think you will see
> that
> > > this is the height of the left pelvis joint. Since the hip and
> knee
> > > is driven, and the foot is driven to be flat on the floor this
> > means
> > > the leg provides the height of the hipjoint. Instead of the
> height
> > > you could also drive the rotation of the pelvis around the
global
> x
> > > axis.
> > >
> > > The other one is the position of the left hip joint in the x
> > > direction, which was previously controlled via the x position
of
> > the
> > > foot. You could also say that it is the rotation of the pelvis
> > around
> > > the global Z direction.
> > >
> > > So to make the standing model work you need to apply these two
> > > additional drivers.
> > >
> > > Please do hesitate to ask again if you have further questions
> > >
> > > Best regards
> > > Søren, AnyBody Support
> > >
> > >
> > > — In anyscript@yahoogroups.com, “sebastian.kreissl”
> > > <sebastian.kreissl@> wrote:
> > > >
> > > > Hello everybody,
> > > > I am trying to create a model that stands on one leg only.
> First
> > > off, I
> > > > just removed the lines, from the regular StandingModel where
> the
> > > left
> > > > leg is fixed to the ground, that (obviously) lead to a
> > > kinematically
> > > > indetermined system.
> > > >
> > > > Second try was to combine the FreePostureMove model with the
> > > > StandingModel:
> > > > 1. Use the StandingModel as a basis
> > > > 2. Comment out the lines where left toe and heel are fixed to
> the
> > > ground
> > > > 3. Copy the lines from FreePostureMove where the left leg is
> > > defined,
> > > > to the StandingModel
> > > >
> > > > Thus I was hoping that I could create a correct model however
> it
> > is
> > > not
> > > > compatible: the message window gives me error messages that
> some
> > > > dimensions do not match. And contains too few kinematic
> > constraints.
> > > >
> > > > Has anybody tried (maybe already succeeded) to create a model
> > that
> > > > stands on one leg only.
> > > >
> > > > Advices, suggestions would be highly appreciated
> > > >
> > > > Regards Sebastian
> > > >
> > >
> >
>