Try and stay out of the line of sight with the rocket launcher thing on the ceiling that has the laser sight. Also stay off the parts of the floor that glow reddish. The two of those together plus him hitting you do lots of damage, so just be careful of where you are standing.
It's all about getting the nanosynth controllers (green lantern-looking guys) dead so they can't heal the surrounding bots. CC as much as you can.
I don't have too much trouble with this part as a controller since I can stun/lift the nanosynth and use psychic resonance as an instant group stun. Just take it slow and don't hit the next security panel until every mob is dead.