# Squatting Model

Dear all,

My name is Jawad, I have a BSc in Industrial Engineering and I’m doing
my MSc in Engineering Management. I’m working on a small project to in
vestigate the effect of the knee position while squatting on the torque
generated in the knees; literature suggests not to make the knees
travel more than the toes; I need to simulat this situation and test
the model on a small group of people.

I am using Anybody Modeling System 3.0 to do that, I did not
finish all the tutorials yet; I have a question though:

In the squatting example that you get from the respiratory, how can I
modify the model so as to fix the knees in a vertical position and
not
allow them to move past the feet? In the current model, the knees go
beyond the feet, I want to fix them, of course at the same time, the
hips have to go back.

Any idea how I can do that?

Thank you.

Hi Jawed

Welcom to the group

I am a little unsure which model you are referring to, but I assume that it
is the Lunge model.

This model is driven by recorded markers, the motion has been found using
the gaitapplication2, your question resembles the previous question by Andy

The fundamental problem is that there is no quick way of changing this
motion, since the model is based on a recording there are no parameters that
directly allow you to change the motion as you desire.

What you could do instead is to create your own motion, and create drivers
for each joint that will give you the desired motion and parameterization.
For this purpose the StandingModel may be a good basis because it already
has connection to the ground. Then you will need to change some of its
drivers, here it may be useful to look at the drivers for the
FreePostureMove model. This model allows you to driver each joint by a set
of values in an interpolation function.

Best regards

SÃ¸ren, AnyBody Support

From: anyscript@yahoogroups.com [mailto:anyscript@yahoogroups.com] On Behalf
Sent: 29 November 2008 11:24
To: anyscript@yahoogroups.com
Subject: [AnyScript] Squatting Model

Dear all,

My name is Jawad, I have a BSc in Industrial Engineering and I’m doing
my MSc in Engineering Management. I’m working on a small project to in
vestigate the effect of the knee position while squatting on the torque
generated in the knees; literature suggests not to make the knees
travel more than the toes; I need to simulat this situation and test
the model on a small group of people.

I am using Anybody Modeling System 3.0 to do that, I did not
finish all the tutorials yet; I have a question though:

In the squatting example that you get from the respiratory, how can I
modify the model so as to fix the knees in a vertical position and
not
allow them to move past the feet? In the current model, the knees go
beyond the feet, I want to fix them, of course at the same time, the
hips have to go back.

Any idea how I can do that?

Thank you.

[Non-text portions of this message have been removed]

Dear Soren,

I checked Andy’s post, but it is not similar to mine; I am refering
to a squat model, not a lunge model. The squat model is usually found
in the InterfaceFeatures tutorial. The squat model has drivers
defined already, but I’m not sure how they work.

If you like, I can attach the squat model.

Regards,

— In anyscript@yahoogroups.com, AnyScript Support
<anyscriptsup@…> wrote:
>
> Hi Jawed
>
>
>
> Welcom to the group
>
>
>
> I am a little unsure which model you are referring to, but I assume
that it
> is the Lunge model.
>
>
>
> This model is driven by recorded markers, the motion has been found
using
> the gaitapplication2, your question resembles the previous question
by Andy
>
>
>
> The fundamental problem is that there is no quick way of changing
this
> motion, since the model is based on a recording there are no
parameters that
> directly allow you to change the motion as you desire.
>
>
>
> What you could do instead is to create your own motion, and create
drivers
> for each joint that will give you the desired motion and
parameterization.
> For this purpose the StandingModel may be a good basis because it
> has connection to the ground. Then you will need to change some of
its
> drivers, here it may be useful to look at the drivers for the
> FreePostureMove model. This model allows you to driver each joint
by a set
> of values in an interpolation function.
>
>
>
>
>
> Best regards
>
> SÃ¸ren, AnyBody Support
>
>
>
>
>
>
>
>
>
>
>
> _____
>
> From: anyscript@yahoogroups.com [mailto:anyscript@yahoogroups.com]
On Behalf
> Sent: 29 November 2008 11:24
> To: anyscript@yahoogroups.com
> Subject: [AnyScript] Squatting Model
>
>
>
> Dear all,
>
> My name is Jawad, I have a BSc in Industrial Engineering and I’m
doing
> my MSc in Engineering Management. I’m working on a small project to
in
> vestigate the effect of the knee position while squatting on the
torque
> generated in the knees; literature suggests not to make the knees
> travel more than the toes; I need to simulat this situation and
test
> the model on a small group of people.
>
> I am using Anybody Modeling System 3.0 to do that, I did not
> finish all the tutorials yet; I have a question though:
>
> In the squatting example that you get from the respiratory, how can
I
> modify the model so as to fix the knees in a vertical position and
> not
> allow them to move past the feet? In the current model, the knees
go
> beyond the feet, I want to fix them, of course at the same time,
the
> hips have to go back.
>
> Any idea how I can do that?
>
> Thank you.
>
>
>
>
>
> [Non-text portions of this message have been removed]
>

Hi Jawed,

The squat model from the tutorial uses mostly measured data for driving the
joints. You can see all the AnyKinInterPolDrivers which directly use
experimental data. The Center of Mass is also driven to some data values,
which means that the ShoulderJoint is free to be used to balance the model.
You can constrain the knee to stay above the feet by creating a linear
measure between the knee and e.g. the global ref and drive this value so
that it slides in the desired plane. Of course you have to get rid of
standing model of the Repository. It adjusts the ankle so that the CoM is
placed above. You can simply modify the Mannequin file to get the squat
motion, and then add the linear measure mentioned above. And in case you
have experimental motion data, go with the Gaitapplication2 like Soeren
suggested. Please see the UniGaitMiami example for details.

Best regards,

Sebastian

From: anyscript@yahoogroups.com [mailto:anyscript@yahoogroups.com] On Behalf
Sent: 2. december 2008 15:31
To: anyscript@yahoogroups.com
Subject: [AnyScript] Re: Squatting Model

Dear Soren,

I checked Andy’s post, but it is not similar to mine; I am refering
to a squat model, not a lunge model. The squat model is usually found
in the InterfaceFeatures tutorial. The squat model has drivers
defined already, but I’m not sure how they work.

If you like, I can attach the squat model.

Regards,

— In anyscript@yahoogrou <mailto:anyscript%40yahoogroups.com> ps.com,
AnyScript Support
<anyscriptsup@…> wrote:
>
> Hi Jawed
>
>
>
> Welcom to the group
>
>
>
> I am a little unsure which model you are referring to, but I assume
that it
> is the Lunge model.
>
>
>
> This model is driven by recorded markers, the motion has been found
using
> the gaitapplication2, your question resembles the previous question
by Andy
>
>
>
> The fundamental problem is that there is no quick way of changing
this
> motion, since the model is based on a recording there are no
parameters that
> directly allow you to change the motion as you desire.
>
>
>
> What you could do instead is to create your own motion, and create
drivers
> for each joint that will give you the desired motion and
parameterization.
> For this purpose the StandingModel may be a good basis because it
> has connection to the ground. Then you will need to change some of
its
> drivers, here it may be useful to look at the drivers for the
> FreePostureMove model. This model allows you to driver each joint
by a set
> of values in an interpolation function.
>
>
>
>
>
> Best regards
>
> SÃ¸ren, AnyBody Support
>
>
>
>
>
>
>
>
>
>
>
> _____
>
> From: anyscript@yahoogrou <mailto:anyscript%40yahoogroups.com> ps.com
[mailto:anyscript@yahoogrou <mailto:anyscript%40yahoogroups.com> ps.com]
On Behalf
> Sent: 29 November 2008 11:24
> To: anyscript@yahoogrou <mailto:anyscript%40yahoogroups.com> ps.com
> Subject: [AnyScript] Squatting Model
>
>
>
> Dear all,
>
> My name is Jawad, I have a BSc in Industrial Engineering and I’m
doing
> my MSc in Engineering Management. I’m working on a small project to
in
> vestigate the effect of the knee position while squatting on the
torque
> generated in the knees; literature suggests not to make the knees
> travel more than the toes; I need to simulat this situation and
test
> the model on a small group of people.
>
> I am using Anybody Modeling System 3.0 to do that, I did not
> finish all the tutorials yet; I have a question though:
>
> In the squatting example that you get from the respiratory, how can
I
> modify the model so as to fix the knees in a vertical position and
> not
> allow them to move past the feet? In the current model, the knees
go
> beyond the feet, I want to fix them, of course at the same time,
the
> hips have to go back.
>
> Any idea how I can do that?
>
> Thank you.
>
>
>
>
>
> [Non-text portions of this message have been removed]
>

[Non-text portions of this message have been removed]