That depends on where you fight them. if you go directly down from the stairs or elevator then yes, you'll probably face multip,e robos even if not seen by a cam, that is because of the patrol route. If a friendly nearby robot is engaging the nearby robots will help. If instead of going south you go right of the stair on the uppermost corridor you'll reach eventually a T shaped intersection. You comming from the left, on the right there will be a locked door and the passage down is patrolled by a robot. Ambush the robot at the T intersection when it moves into it. If you have stealth that is the better way to engage... Fight the robot there and you'll fight it alone. Only on the most extreme of cases does a second show up mid fight but savescumming will help you there. Now that lower passage opens into an O shaped room, the second robot patrols that room as well a the lower middle hallway. You can engage that robot nearly from the T shaped intersection and I advise you to do so, if needed provoke the robot and retreat there so it will come after you alone. Once you kill that one there is only one robot left patrolling the lower corridor.