I've tried to incorporate "X" into the design when possible in the past -- which isn't terribly hard since it appears in trusses all the time -- but we've been moving away from that and trying to use the lightest material for the task to start with and lightening as little of the robot and its parts later.
I don't know how 'signature' that is, though, since I doubt that anyone has noticed. Last season, I cut lightening holes into a beam that, when read as morse code, spelled "XBOT," but the tube collapsed as a result.
