I think it's about time to resurrect this discussion about adding GPS messages to sensor_msgs for the Diamondback release. Getting the messages defined early and committed to unstable will provide people a chance to experiment with them before interfaces get frozen for the release. I am interested in participating. Let's discuss options some more here on the mailing list. If there is a consensus on a fairly concrete approach, we could probably start a package proposal and API review on it soon after. On Fri, May 21, 2010 at 11:05 PM, Bill Morris wrote: > On Fri, 2010-05-21 at 22:03 -0500, Jack O'Quin wrote: >> On Fri, May 21, 2010 at 9:35 PM, Tully Foote wrote: >> >> > With regards to a location of a potential GPS message within the ROS package >> > ecosystem, as the maintainer of common_msgs this seems like a strong >> > candidate for inclusion in the sensor_msgs package. >> >> Good idea. I hadn't thought of that. I was imagining a new package >> defining both the messages and some utility functions. >> >> Putting just the messages in sensor_msgs is better. There might end up >> being two or three messages, depending on how people decide to >> structure it. > > sensor_msgs seems like a good place for the messages. I think it should > be three messages; GPS fix, status and waypoints/landmarks. A message > that describes a moving object may also be useful for swarming aircraft. > >> > As for the library components doing a package proposal for gps_common would >> > be a good idea. >> >> I just realized that Ken Tossell already has a gps_common package in >> the umd-ros-pkg (University of Maryland). Looks like it only has a >> message definition right now. >> >> Whether we call it that or something similar, should it be a separate >> stack or part of some existing one? > > I would guess that the gps related functions belong in a package in the > navigation stack. I think gps_common sounds like a reasonable name. > > Great circle distance between the current gps position and waypoints > would be a useful function. Functions to calculate the heading to the > next waypoint and time to next way point at current speed may also be > useful. > > I imagine a waypoint/landmark being a position with a rectangular of > spherical volume, an optional desired heading, and a text label. > > I am willing to try to find some time this weekend to put together the > review page with a summary of the current ideas for the package and > messages if/when we have consensus on where they belong. --  joq