@JWhitleyWork Thanks for starting the thread and also opening the PR.
Now that common_msgs is relatively mature we generally want to make sure that messages are already in use and have been tested, instead of developing them in the abstract here. There’s some notes on contributing on the wiki page
We generally want things to have been validated by real use in the field before merging them into common_messages so that we can be confident that they are useful. Sometimes new messages here will also be a merge of two or more messages to standardize. Such as here for the BatteryState message.
There may be several classes of Radar returns that would be good to clarify/separate. There are potentially low level interfaces (range, intensity, velocity) as well as high level interfaces (object position, velocity, and scale). Surveying the field of sensors and understanding which ones can be covered by any given interface would be valuable in this process. And I’m sure that there are users with radar messages already that would be great to get their feedback and look for an already tested version of a radar message.