Hi Italo,
Unfortunately Robot don't support steel connection for America design codes, because they are not yet implemented. EC8 verification are not implemented in Robot for connections.
If you need to perform steel connection design with American standard, I can suggest you to use advance steel. You can transfer your model from Robot to advance steel with all the calculation results (it require a lot of time) and then, in advance steel you can define your connection (geometrical parameters) and then run the design checks.
The result report is not so sexy such as the robot one, but it cover a lot of steel connection type, much more then Robot.
One suggestion: if you need to have the report in English, or another language, you have to install the right language pack.

PasProStudio
www.pasquiniprogetti.eu
Structural + Detailing engineers