Events Calendar

EE-EP Seminar, Ashwin Seshia, January 13th, EEB 132 @ 11:00am

Speaker: Ashwin A. Seshia, University of Cambridge

Talk Title: Dynamics-Enhanced Sensory Processing

Abstract: Instruments based on resonant and oscillatory elements have historically been employed to conduct some of the most accurate physical measurements. This talk describes research to enable miniaturized electromechanical sensor systems wherein precise engineering of the dynamical response is instrumental in enabling new modes of transduction, energy conversion and sensing. A series of research results from my group will be provided to illustrate the approach. First, seismic-grade accelerometers based on resonant output principles will be described where the interaction of mechanical nonlinearities and noise processes sets limits on the achievable resolution. Further, by engineering the principle of vibration mode localization in weakly coupled resonators, passive immunity to environmental drift is achieved by recording eigenstate variations as a measure of differential structural perturbations. Next, net-zero power strain sensors for structural health monitoring applications are enabled by integrating vibration energy harvesters together with low-power temperature compensated resonant strain gauges. By engineering the principle of parametric resonance for vibration energy harvesting it is possible to engineer vibration energy harvesters with multi-frequency responsivity and substantially larger recoverable electrical power as compared to classical approaches based on direct (linear) resonance under specified conditions. Finally, with a view towards future application of engineered non-linearity in micro- and nanoelectromechanical systems, I will describe results from electro-acoustic biosensors utilizing noise and non-linear response as readout modalities, and the mutual synchronization of non-linear microelectromechanical oscillators demonstrating significantly improved frequency stability and potentially enabling fundamentally new energy-efficient approaches to sensory information processing. Micro- and nanofabricated devices engineered using these and similar approaches are now being integrated into monitoring tools and sensor systems for a variety of application scenarios.

Biography: Ashwin A. Seshia received the B. Tech. degree in engineering physics from IIT Bombay, India, in 1996; the M.S. and Ph.D. degrees in electrical engineering and computer science from the University of California at Berkeley, Berkeley, CA, USA, in 1999 and 2002, respectively; and the M.A. degree from the University of Cambridge, Cambridge, U.K., in 2008. He joined the faculty of the Department of Engineering, University of Cambridge, in 2002, where he is currently a Reader in Microsystems Technology and a Fellow of Queens' College. His Research interests are in the domain of micro- and nano-engineered dynamical systems. He serves on the editorial boards of the IEEE Journal of Microelectromechanical Systems, the IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, IOP Journal of Micromechanics and Microengineering, and the IEEE Transactions of Nanotechnology.

Host: EE-Electrophysics

Location: Hughes Aircraft Electrical Engineering Center (EEB) - 132

Audiences: Everyone Is Invited

Contact: Marilyn Poplawski