Part of the problem is that the definition of robot can be a bit of a slippery slope. Can a spacecraft which has autonomous docking capability be considered a potential robot for example? If you are counting spacecraft, assume one of each kind you are counting is present.
And for this question, a robot does not necessarily need to be autonomous. A spacecraft remotely controlled could be a robot for this question for example. If something is officially robotic, it's a robot.
To further narrow it down, for this question a robot should have some mobility. It should be able to move or orient itself — or at least appendages or parts of itself — without someone (a human) grabbing it and moving it, or d be able to move/orient another substantial object in a complex manner.
Science packages may have little gizmos that feed animals or mix, aliquot, or titrate liquids for example. If you know of some cool or prominent ones, count 'em!
Routine movement like pumps to periodically circulate fluids (e.g. water) or fans or magnetic pickups on old-style hard drives would not be robots for example.
And don't forget to count the ones that just plain look like robots!
