Hi! I’m new in this field of AnyBody simulations and I have already
done a few examples and played around. I have to do a project for on my
University for Applied Science in AnyBody and I need a helping hand.
What I wanna do in my first step is to simulate a skier during his
carving swing. This should be done with marker trajectory. I have no
mocap data yet but I primarily want to know what the best approach to
this problem is?
My second question is: If I get an error due to too few kinematic
constraints, how do I know which segment or joint the software means? I
actually have no idea where the error is located in the Anyscript or
which part of the body is kinematically underconstraint?
Best Regards,
Thomas Koller
(Study for MSc in Sports Equipment Technologies on the University for
Applied Science in Vienna/Austria)
Hello.
I have worked with cross-country skiing (mostly double-poling, see http://www.anybodytech.com/199.0.html#c250) but I think your
application might be a lot harder. Therefore, I would like to ask:
what’s your end goal? And, what do you hope to achieve with an
AnyBody simulation? It is hard (for me anyway) to give any kind of
recommendation without this knowledge.
/jokke
— In anyscript@yahoogroups.com, “kollair12345” <kollair12345@…>
wrote:
>
> Hi! I’m new in this field of AnyBody simulations and I have already
> done a few examples and played around. I have to do a project for
on my
> University for Applied Science in AnyBody and I need a helping
hand.
> What I wanna do in my first step is to simulate a skier during his
> carving swing. This should be done with marker trajectory. I have
no
> mocap data yet but I primarily want to know what the best approach
to
> this problem is?
> My second question is: If I get an error due to too few kinematic
> constraints, how do I know which segment or joint the software
means? I
> actually have no idea where the error is located in the Anyscript
or
> which part of the body is kinematically underconstraint?
>
> Best Regards,
> Thomas Koller
>
> (Study for MSc in Sports Equipment Technologies on the University
for
> Applied Science in Vienna/Austria)
>
Hi! Thanks a lot for the quick answer!
My end goal is to simulate an inverse rotation crash of a skier and I
primarily want to measure the forces in the knee as well as the
muscle forces. So I thought firstly it might be helpful to move the
body model like a skier to make further changes to simulate the crash
in a final step. I guess that this is probably a good approach to the
problem because there are no motion capturing data from a crash
available yet.
What do you think?
This investigation should help to optimize ski bindings or to make
them saver in the case of crash!
If I try to drive the right leg model with a marker fitted on the
foot, the model is kinematically not determined. So how do I know
what exactly is wrong or where the error is located in the model?
It’s no problem to do this with drivers if I place one in every joint
(hip, knee and ankle) but if it is also not possible to do it with
just one driver on the foot like in AnyBikeDemo.
Best Regards,
Tom
— In anyscript@yahoogroups.com, “joakim_holmberg” <jokke@…> wrote:
>
> Hello.
> I have worked with cross-country skiing (mostly double-poling, see
> http://www.anybodytech.com/199.0.html#c250) but I think your
> application might be a lot harder. Therefore, I would like to ask:
> what’s your end goal? And, what do you hope to achieve with an
> AnyBody simulation? It is hard (for me anyway) to give any kind of
> recommendation without this knowledge.
> /jokke
>
> — In anyscript@yahoogroups.com, “kollair12345” <kollair12345@>
> wrote:
> >
> > Hi! I’m new in this field of AnyBody simulations and I have
already
> > done a few examples and played around. I have to do a project for
> on my
> > University for Applied Science in AnyBody and I need a helping
> hand.
> > What I wanna do in my first step is to simulate a skier during
his
> > carving swing. This should be done with marker trajectory. I have
> no
> > mocap data yet but I primarily want to know what the best
approach
> to
> > this problem is?
> > My second question is: If I get an error due to too few kinematic
> > constraints, how do I know which segment or joint the software
> means? I
> > actually have no idea where the error is located in the Anyscript
> or
> > which part of the body is kinematically underconstraint?
> >
> > Best Regards,
> > Thomas Koller
> >
> > (Study for MSc in Sports Equipment Technologies on the University
> for
> > Applied Science in Vienna/Austria)
> >
>
Hello.
I’m not familiar with an “inverse ratation crash”, though I can
imagine (or at least guess) what you mean. Do you expect to get mocap
data from such an unpleasant event for a skier?
Anyway, Do you have an idea of the forces (magnitude and direction)
at the feet (or foot)? If so, you may be able to use just one leg (or
perhaps two) and approximate the upper-body with a “HAT-segment” to
get the mass and inertia properties. Also, the trajectory (movement
of the skis) might be roughly approximated from ordinary video.
In short, what kind of motion and external forces do you have (more
or less accurate)?
About the kinematic problems, just driving a point of the foot does
not tell the ankle, knee and hip how to move since there are several
possible “angle combinations”.
/jokke
— In anyscript@yahoogroups.com, “kollair12345” <kollair12345@…>
wrote:
>
> Hi! Thanks a lot for the quick answer!
> My end goal is to simulate an inverse rotation crash of a skier and
I
> primarily want to measure the forces in the knee as well as the
> muscle forces. So I thought firstly it might be helpful to move the
> body model like a skier to make further changes to simulate the
crash
> in a final step. I guess that this is probably a good approach to
the
> problem because there are no motion capturing data from a crash
> available yet.
> What do you think?
> This investigation should help to optimize ski bindings or to make
> them saver in the case of crash!
>
> If I try to drive the right leg model with a marker fitted on the
> foot, the model is kinematically not determined. So how do I know
> what exactly is wrong or where the error is located in the model?
> It’s no problem to do this with drivers if I place one in every
joint
> (hip, knee and ankle) but if it is also not possible to do it with
> just one driver on the foot like in AnyBikeDemo.
>
> Best Regards,
> Tom
>
>
>
>
> — In anyscript@yahoogroups.com, “joakim_holmberg” <jokke@> wrote:
> >
> > Hello.
> > I have worked with cross-country skiing (mostly double-poling,
see
> > http://www.anybodytech.com/199.0.html#c250) but I think your
> > application might be a lot harder. Therefore, I would like to
ask:
> > what’s your end goal? And, what do you hope to achieve with an
> > AnyBody simulation? It is hard (for me anyway) to give any kind
of
> > recommendation without this knowledge.
> > /jokke
> >
> > — In anyscript@yahoogroups.com, “kollair12345” <kollair12345@>
> > wrote:
> > >
> > > Hi! I’m new in this field of AnyBody simulations and I have
> already
> > > done a few examples and played around. I have to do a project
for
> > on my
> > > University for Applied Science in AnyBody and I need a helping
> > hand.
> > > What I wanna do in my first step is to simulate a skier during
> his
> > > carving swing. This should be done with marker trajectory. I
have
> > no
> > > mocap data yet but I primarily want to know what the best
> approach
> > to
> > > this problem is?
> > > My second question is: If I get an error due to too few
kinematic
> > > constraints, how do I know which segment or joint the software
> > means? I
> > > actually have no idea where the error is located in the
Anyscript
> > or
> > > which part of the body is kinematically underconstraint?
> > >
> > > Best Regards,
> > > Thomas Koller
> > >
> > > (Study for MSc in Sports Equipment Technologies on the
University
> > for
> > > Applied Science in Vienna/Austria)
> > >
> >
>