634 MINIATURE DIRECT DRIVE ROTARY ACTUATORS R. S. Wallace, April 1993 This paper reports the development of direct drive DC motor actuators for miniature robots. The motors are based on Nd-Fe-B rare earth permanent magnets and controlled by low cost microcontrollers. The motors have low friction, small size, high speed, low construction cost, no gear backlash, operate safely without limit switches, have limited self-braking, and generate moderate torque. Significantly, one motor can generate enough torque to lift a second motor of about the same size against the force of gravity, at a distance approximately equal to the size of the motor, without resorting to the use of a counterweight. We demonstrated the feasibility of using these actuators to make a two-link robot finger or leg.