Dr. Xin (Cindy) Yee
Assistant Professor
Department of Mechanical and Aerospace Engineering
University of Colorado Colorado Springs
January 13, 2026
Encapsulated microbubbles (EMBs) are used in biomedicine for both diagnostic and therapeutic purposes that include ultrasound imaging and targeted drug delivery. A data-driven method to control the oscillations of EMBs using the applied acoustic field is presented based on Koopman operator theory, which is a method for transforming a nonlinear dynamical system on a state space into a linear system on an infinite-dimensional function space. This method preserves the underlying nonlinear dynamics of the system, and the function spaces can be approximated through data-driven methodologies, which enables the application of classical linear control strategies to the nonlinear system. Here, we apply a Koopman linear quadratic regulator (KLQR) to control the nonlinear oscillations of a EMB through the applied acoustic field. Results are presented that demonstrate the effectiveness of the modified KLQR controller in driving the EMB to follow arbitrarily-prescribed radial oscillations and stabilize at nonequilibrium radii.
Bio: Dr. Xin (Cindy) Yee is an Assistant Professor in the Department of Mechanical and Aerospace Engineering at the University of Colorado-Colorado Springs. She received her Bachelor of Science degree in Mechanical Engineering from MIT and both Master’s and Ph.D. degrees in Engineering from Caltech. Her expertise is in data science applications within engineering sciences.
Contact: Jin Yang (jin.yang@austin.utexas.edu)