KUKA LBR4+ dynamic parameters

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PuntatoreNullo
Posts: 2
Joined: 02 Sep 2013, 18:03

KUKA LBR4+ dynamic parameters

Post by PuntatoreNullo »

Hello everyone!

I am using in V-Rep the KUKA LBR4+ CAD model supplied by KUKA. I have a question regarding the dynamic parameters values which are inserted in the model (I mean, masses, centers of gravity, inertia tensors,...): in your experience, are those values actual or, at least, realistic? Is it possible to obtain actual torques profiles (given joint trajectories) similar to those which are retrieved by the sensors of the real manipulator itself?

Thank you very much!

Claudio

coppelia
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Posts: 10339
Joined: 14 Dec 2012, 00:25

Re: KUKA LBR4+ dynamic parameters

Post by coppelia »

Hello Claudio,

Are you talking about the KUKA LBR4+ model that comes with the V-REP installation?
In that model, masses are relatively correct. The center of masses (COM) are not from the actual robot, same for the moments of inertia of the parts.
Now, generally, simulation models and real models (irrspective of the maker) differ somewhat, this is for mainly 2 reasons:
  • The embedded physics engines have some limitations and are more stable when cheating a little bit with the parameters.
  • It is sometimes difficult to obtain too precise information from a robot maker. This is not only for the masses, COM, moments of inertia, but also for the motor controller algorithms, which are often kept very secret.
The first point here above can very soon be relaxed, since V-REP will soon support a high fidelity physics engine (Vortex) which produces more stable and precise values.

Cheers

PuntatoreNullo
Posts: 2
Joined: 02 Sep 2013, 18:03

Re: KUKA LBR4+ dynamic parameters

Post by PuntatoreNullo »

Thank you very much!

Cheers,
Claudio

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