Efficient miniature actuators that are light, compact, and driven by low power are needed to drive telerobotic devices and space mechanisms in future NASA missions. Examples of space mechanisms and devices that require actuators include robotic arms, miniature rovers, release mechanisms, positioning devices, aperture opening and closing devices, and real-time compensation for thermal expansion in space structures. These motors need to operate at various temperatures and pressures with a large range of thermal variations over a relatively short period swing. Ultrasonic rotary motors have the potential to meet this NASA need and they were developed as actuators for miniature telerobotic applications. These motors were adapted for operation in the environment of Mars, which includes very low temperatures and vacuum. A hybrid analytical model, including the influence of the rotor and stator dynamics, friction effects, and interface effects, was developed to design an efficient ultrasonic motor as a complete system. In parallel, efforts have been made to determine the thermal and vacuum performance of these motors, and effective operation at temperatures as low as −150<th>°C and at a pressure of 16 mtorr were demonstrated. To explore telerobotic applications for USMs a robotic arm was constructed with such motors.