Ask Your Question
2

Setting inertia for a whole robot

asked 2011-08-25 02:57:33 -0500

erpa gravatar image

Hi all, I am trying to model a quadrotor, i have the .model file from an old implementation in gazebo but i need to rewrite it as a .urdf to be used in ROS. My problem is that rather then setting the inertia for each link i would like to set it for the whole robot (in fact the controller will consider the quadrotor as a unique body). Is it possible somehow?

Thank you

edit retag flag offensive close merge delete

1 Answer

Sort by ยป oldest newest most voted
0

answered 2011-08-25 11:59:37 -0500

hsu gravatar image

...moving my comment here as I ran out of room :)

If the links are connected via fixed joints, you should be able to assign inertia to any one of the fixed-joint-connected links and set the rest of the links inertia to some very small numbers (1e-6). As of diamondback, inertia of fix-joint-connected links are lumped into their parent. In general, 0 inertia will not work as the urdf2gazebo parser will ignore the link and break the kinematic chain.

On the other hand, non-fixed-joint-connected links with inertia close to 0 might make your dynamics unstable.

edit flag offensive delete link more

Comments

thanks a lot for your help
erpa gravatar image erpa  ( 2011-08-29 01:08:17 -0500 )edit

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools

Stats

Asked: 2011-08-25 02:57:33 -0500

Seen: 289 times

Last updated: Aug 25 '11