Rotational Jacobian

classic Classic list List threaded Threaded
2 messages Options
Reply | Threaded
Open this post in threaded view
|

Rotational Jacobian

Chris Dellin
Hey all,

I did a few experiments with the WAM model, and the KinBody::CalculateRotationJacobian routine always gives numbers that are twice what I expect.  I looked at the source in src/libopenrave/KinBody.cpp, and I think the result should include a 0.5 term for each quaternion derivative component (see the very end of http://www.mathworks.com/help/toolbox/physmod/mech/gs/f13-7317.html).  Have others noticed similar problems?

Thanks,
- Chris Dellin

------------------------------------------------------------------------------
Start uncovering the many advantages of virtual appliances
and start using them to simplify application deployment and
accelerate your shift to cloud computing
http://p.sf.net/sfu/novell-sfdev2dev

_______________________________________________
Openrave-users mailing list
[hidden email]
https://lists.sourceforge.net/lists/listinfo/openrave-users
Reply | Threaded
Open this post in threaded view
|

Re: Rotational Jacobian

Rosen Diankov
Administrator
hi chris,

you are right, it should have been multiplied by 0.5. This is fixed in
(r1729). Thanks!

rosen,

2010/9/12 Chris Dellin <[hidden email]>:

> Hey all,
> I did a few experiments with the WAM model, and
> the KinBody::CalculateRotationJacobian routine always gives numbers that are
> twice what I expect.  I looked at the source in src/libopenrave/KinBody.cpp,
> and I think the result should include a 0.5 term for each quaternion
> derivative component (see the very end
> of http://www.mathworks.com/help/toolbox/physmod/mech/gs/f13-7317.html).
>  Have others noticed similar problems?
> Thanks,
> - Chris Dellin
> ------------------------------------------------------------------------------
> Start uncovering the many advantages of virtual appliances
> and start using them to simplify application deployment and
> accelerate your shift to cloud computing
> http://p.sf.net/sfu/novell-sfdev2dev
>
> _______________________________________________
> Openrave-users mailing list
> [hidden email]
> https://lists.sourceforge.net/lists/listinfo/openrave-users
>
>

------------------------------------------------------------------------------
Start uncovering the many advantages of virtual appliances
and start using them to simplify application deployment and
accelerate your shift to cloud computing
http://p.sf.net/sfu/novell-sfdev2dev
_______________________________________________
Openrave-users mailing list
[hidden email]
https://lists.sourceforge.net/lists/listinfo/openrave-users