We describe the construction of a motorized optical rotation mount with a 40 mm clear
aperture. The device is used to remotely control the power of large diameter laser beams for
a magneto-optical trap. A piezo-electric ultrasonic motor on a printed circuit board provides
rotation with a precision better than 0.03 and allows for a very compact design. The rotation
unit is controlled from a computer via serial communication, making integration into most
software control platforms straightforward.