Hi, I am keen on reading an answer to this answers.ros.org question: http://answers.ros.org/question/2803/when-should-i-send-geometric-information-over-a "When should I send geometric information over a topic as opposed to TF?" I would think that TF is the best place to publish frames, meaning coordinate systems to be used as a point of reference for other geometric data. So this would be ideal for robot joints/links, sensor coordinate systems, and perceived joints/links of other agents (humans or robots). If possible, all those should rather be published in TF rather than anything else, I would believe. However I do not yet understand whether there is a downside to using TF, or some kind of degradation when plenty of frames are being published. The only thing I can think of is that rosbag and rxbag cannot treat individual transforms, they can only record / replay the whole tf tree. Also I guess that data with a lot of noise is not suitable as a reference frame for anything, so there is no point in publishing that in TF. Other thoughts? cheers, Thibault