ABSTRACT New DRIE actuator systems have been developed which use a high-force, linear actuator to wrap a flexible brake band around the rigid brake shoe of a large-deflection, rotary actuator. The brake can hold the rotary actuator at any arbitrary location within its full range of travel. A third actuator may be used to engage a pair of locking pins in order to keep the brake motor extended in the event of a power failure. The 100× increase in rotational stiffness after the brake is applied raises the fundamental resonant frequency by more than an order of magnitude, enabling precision optical adjustments over a large tuning range in the presence of external shock and vibration. optical devices described at HH2002 [4]. A cavity formed in an INTRODUCTION With the improved stability from advances in suspension design, comb drive actuators are being deployed in applications requiring ever larger deflections. With total ranges in the hundreds of microns, the sub-micron positioning required for many applications is increasingly difficult to achieve, especially with the shocks and vibrations experienced in a product environment. This problem is commonly addressed in macroscopic applications by mounting small-deflection end effectors to large-deflection coarse positioners. However, this is less attractive with micromachined electrostatic actuators due to the additional fabrication complexity involved. An actuator with a mechanical brake provides similar functionality by increasing the suspension stiffness of the system to accomplish fine positioning once the coarse position has been set. Moreover, the brake may be used to implement a latching function, maintaining the actuated position of the motor in the event of a power failure or in applications requiring zero steady-state power. As shown schematically in Fig. 1, DRIE actuators have been developed with mechanical braking mechanisms somewhat analogous to a drum brake in an automobile. Initial contact occurs between the vertical sidewalls in the center of the brake band, and the contact area increases as the brake actuator causes the band to wrap around the brake shoe.