From: owner-3dui@hitl.washington.edu on behalf of Ivan Poupyrev
[poup@csl.sony.co.jp]
Sent: Tuesday, December 19, 2000 9:35 PM
To: 3-D User Interaction Mailing List
Subject: Re: Modelling of user induced forces

Did you look at the VR2000 paper "Physically-based manipulation
on the responsive workbench" by Bernd Frohlich?

ivan

----- Original Message ----- 
From: "Anders Backman" <andersb@cs.umu.se>
To: "3-D User Interaction Mailing List" <3d-ui@hitl.washington.edu>
Sent: Tuesday, December 19, 2000 12:48 AM
Subject: Modelling of user induced forces


> Hi,
> 
> We use magnetic tracking to interact with objects
> in a VR-model. The objects are rigid-bodies
> simulated in real time.
> We introduce user interaction using a constraint
> that reduces all six degrees of freedom (MathEngine's
> FixedPathFixedOrientation joint) of the object and we
> integrate the resulting problem (semi) implicitly for
> stability.
> 
> As usual, user induced forces tend to become too
> large and thus we need to limit the forces by using a
> non-linear joint that becomes softer with increasing
> force until it suddenly breaks.
> Does anyone know of a systematic study of such
> models, or other aspects of introducing user
> induced forces into a physical simulation?
> 
> Cheers,
> /Anders
> 
> ________________________________________________________________
>  Anders Backman               Email:    andersb@cs.umu.se
>  HPC2N/VRlab                  Phone:    +46 (0)90-786 9936
>  Umea university              Cellular: +46 (0)70-392 64 67
>  S-901 87 UMEA SWEDEN         Fax:      +46 90-786 6126
>                               http://www.cs.umu.se/~andersb 
>