# what are quaternions and how can I use them?

asked 2011-05-17 09:59:45 -0500

This post is a wiki. Anyone with karma >75 is welcome to improve it.

I have seen quaternions in tf and bullet but I don't know what they are or how to use them.

edit retag close merge delete

Sort by » oldest newest most voted

answered 2011-05-17 10:00:35 -0500

This post is a wiki. Anyone with karma >75 is welcome to improve it.

Quaternions are a representation of orientation wikipedia

For advanced concepts there's an extensive reference written by Erik Dam

There's a good primer on the ogre website.

O.Khatib lectures (from Stanford) on introduction to robotics are freely available from the iTunes U store and can be accessed here. There is a part elaborating on rotation representations.

There's also a great tutorial at https://eater.net/quaternions

more

I encourage to learn the mathematical concept before going on. Wikipedia may serve for this purpose, as KoenBuys said.

( 2013-03-03 03:05:05 -0500 )edit

I started a ROS tutorial. Hopefully others will add to it.

more

Just to complement the idea. A dual quaternion can be used to define a rigid body rotation AND translation of an angle θ about an axis u through the origin. I realy don't known which kind of quaternion is implemented in TF, maybe just the rotational.

Here you can found an interresting web site about quaternions. And here a very good paper with a tutorial and a real application.

more

4
A ROS pose is the position as xyz and a quaternion for rotation.
( 2011-06-17 02:50:33 -0500 )edit