Faculty Host: Professor Jiang Zhong-Ping
Manipulation of friction at the nanoscale is been traditionally approached by chemical means (lubrication). Recent surface force apparatus (SFA) and atomic force microscopy (AFM) experiments demonstrated that it can be done mechanically by applying small perturbation such as vibration to accessible elements of the system. In this talk, I will first present analytic understanding on why vibration can reduce friction based on a 1D model imitating the AFM tip moving on a substrate. Open-loop stability is first studied, and a feedback vibration control is then designed using the accessible variable, i.e., the position of the center of the mass of particles. Control theoretical methods including Lyapunov stability theory and separation of motion in vibration mechanics are applied for the stability analysis and control design. I will further show that with a modification of the sliding friction model, an artificial atomic scale engine can be constructed utilizing the dynamic competition between the intrinsic lengths of the moving object and the supporting carrier. Simulation results will be shown to verify our analytic results.
Dr. Yi Guo is currently an Assistant Professor in the Department of Electrical and Computer Engineering at Stevens Institute of Technology. She obtained her Ph.D. degree in Electrical and Information Engineering from University of Sydney, Australia, in 1999. She was a postdoctoral research fellow at Oak Ridge National Laboratory from 2000 to 2002, and a visiting Assistant Professor at University of Central Florida from 2002 to 2005. Her research interests are mainly in nonlinear systems and control, autonomous mobile robotics, and control of multi-scale complex systems. Her research is supported by NSF, ARMY ARDEC, and DoD. Dr. Guo is a Senior Member of IEEE.