The energy-related activities at Dr. Ghodssi’s MEMS Sensors and Actuators Laboratory (MSAL) are focused on three research thrust areas: development of microball bearing supported micromachines, small scale power sources and energy harvesting. Microball bearings offer a robust and reliable support mechanism that allows operation at high rotational speeds with low friction and wear. Using this technology, micromotors, microturbines and micropumps have been successfully developed, achieving speeds up to ~100,000 rpm. Currently, integration of these modules for next-generation fuel delivery systems as well as implementation of high-power electromagnetic microgenerators is being investigated.
In the field of small-scale energy conversion and storage, researchers at MSAL are utilizing the Tobacco mosaic virus (TMV), a high aspect ratio plant nanostructure, as a nanoscale template for the synthesis of high surface area active battery components and fuel cell catalysts. MEMS-based batteries using TMV-modified electrodes have demonstrated a six-fold increase in battery capacity compared to planar electrode geometries, showing the benefit of using this approach in compact, high performance micro power sources.
Finally, Professor Ghodssi’s group is developing energy scavenging devices using a hybrid piezo/electrostatic approach for harvesting ambient environmental energy using MEMS transducers, with the focus on system-level optimization. In addition to the energy harvesting component, which utilizes piezoelectric beams and variable capacitors, emphasis is placed on devices that facilitate tuning of the system to the frequency of the vibration source, enabling self-adaptive and autonomous microsystems.