Precision Navigation and Timing Enabled by Microtechnology: Are We There Yet?
April 13, 2012
Dr. Andrei Shkel, Program Manager
Defense Advanced Research Project Agency (DARPA)
University of California, Irvine, Professor
Are we there yet? After about two decades of harmonic investment in developments, this is a question impatiently raised over-and-over by potential users of "small technology" for Positioning, Navigation, and Timing (PNT) applications. It is clear that some significant advances have been made over the years, and we see a footprint of the technology in an ever-growing consumer electronic market full of interactive products enabled by inertial and timing micro-technologies. These products include accelerometers for gaming applications gyros for auto safety, and resonators for clocks-just to name a few. The question remains, however: Is the technology really on the level of what we consider to be precision navigation and timing? In reality, "small technology" remains several orders of magnitude short with respect to long-term stability, dynamic range, and accuracy. Why? We don't yet have a complete answer, and we are still working hard to disprove the statement that "high-performance inertial micro-instrument is a contradiction in terms." It is indisputable that we can make things small, but we cannot make them sufficiently precise and uniform. We know we can deposit materials layer-by-layer, but we cannot make micro-devices truly 3-D, as is readily accomplished using conventional machining. We consistently have an excellent case for low-cost and bulk fabrication, but we cannot seriously challenge "boutique" processes when it comes to achieving precision, performance, and stability. We need new knowledge regarding the dimensional stability of materials. We need a better understanding of scaling, surface effects, and fabrication imperfections. PNT applications demand unusual new fabrication technologies and new materials with special properties. To achieve the required phenomenal accuracy, we need a new wave of innovation in design and refinement of many emerging electromechanical transducers. A new wave of innovation in PNT will likely rely on yet-to-be-utilized physics, highly specialized fabrication technologies and batch assembly techniques, selective wafer-level trimming and polishing, a combination of passive and active calibration techniques strategically implemented right on-chip, and introduction of innovative test technologies. This presentation will discuss the growing interest with the Microsystems Technology Office (MTO) of the Defense Advanced Research Projects Agency (DARPA) in the development of a miniature, self-sufficient navigation system that might be realized through deep integration of timing, inertial navigation units, and other non-inertial sensors. A new wave of innovation is underway focused on bringing to life revolutionary ideas and fabrication technologies on micro/nano/pico/femto/atto scales, packaging, ultra-low-power electronics, innovative algorithms, never-before-explored architectures, and exploitation of new integration paradigms.