INSTRUMENT AND SYSTEMS DEVELOPMENT AT THE CHARLES STARK DRAPER LABORATORY, INC.

Draper Laboratory and Boeing North American have formed an alliance to develop very small, lowcost rate sensors for commercial and military applications. Several generations of micromechanical gyroscopes have been developed at Draper, using a dissolved wafer process that features single crystal silicon anodically bonded to a glass substrate. Resulting sensor die size is approximately 1 mm. When integrated with Applications Specific Integrated Circuits (ASIC's), the sensor fits in a 3 cm per side flat pack operating from a single 5 Vdc supply. Bias stability over temperature ranges of 0.5 "C has surpassed 10 "hr. Best to date resolution and angle random walk performance is 25 "/hr in 60 Hz and 0.04 "/dh respectively. The sensors are extremely robust, having survived air guns tests in excess of 60,000 g's. With recent performance improvements, this technology becomes useful for spacecraft inertial guidance. Size, mass, and power of inertial systems can be reduced by orders of magnitude, providing benefits of paramount importance to the new class of miniature satellites, rovers, and spacecraft. However, significant challenges remain before this technology is routinely available for space applications related to performance and space environmental effects. This paper discusses the principle of operation, measured and projected performance, and approaches being taken at Draper Laboratory to develop micromechanical instruments suitable for use in military and space systems.