What kind of motor is this?
Vexta. Grey.
Where did it come from?
The robot on an AMAT RTP tool. An industrial robot.
Is this some sort of specialty motor?
Apparently, since it's impossible to find cheap driver ICs for 5-phase stepping motors.
Is it really .0072 deg/step without microstepping?
I think it's .72 degrees, but it has an integral 100:1 gearbox. There appears to be no way to remove the gearbox.
How you you know it will do 50 KHz?
I don't.
That also seems extraordinarily unlikely
Lame. I wanted to make an RC lawnmower. I want at least 2 m/s. With 30cm wheels, I need about 60RPM. I was going to make a driver with 10 transistors and an ATtiny, but maybe I should forget the whole thing.