It seems that it might be a good idea to design future nuclear reactors with pneumatic-powered robots in mind; purpose-built shafts and ramps could allow robots with minimal electronics into areas unsafe for humans. I say pneumatic instead of hydraulic, as based on my very limited understanding of nuclear physics, lightweight gases are less likely to become neutron activated for extended periods of time.
I could see neutrons activating the parts of a robot, but what physical mechanism would prevent a pneumatic motor from driving some wheels or moving an arm in the presence of radiation, other than the parts heating up and expanding?
One problem I've read in these sorts of situations is the robot eventually or unexpectedly gets killed by the ambient radiation ... and now you have to get humans to dash in there to pull it out of the way.
