Yes, they do. We are using the Cutler Hammer sensorless vector drives.
They detect slippage and will do what they can to make up for the
problem. The method is different from that used with the universal
motors on routers but the effect is very much the same.

Bill

wrote:
Not sure how they work (I'm not a motor engineer), but in the last few
years routers have come to market that ramp up speed on startup, and
the manufacturers claim they compensate for larger loads by "sensing" a
slowdown and automatically increasing power, to maintain nearly
constant speed.
Do any of the lathes out there do this?