Built in episode 1×07, For Queen and Country, Leo was given the ability to download himself into a robotic body in which he could join away missions and just get off the ship. The only draw back to his doing this is that the ship, other then basic life support, will not function, as the main computing center has left. So even though Leo can get off the ship, he rarely does, due to the fact that he's needed to run the ship. Only in extreme emergencies does he download into his robotic form, or, alternatively, whenever the entire crew is going off ship as well.