Stephen Chen

email: stc007@ucsd.edu
linkedin: https://www.linkedin.com/in/histephenchen/

Research Statement

My research interests involve controller and state estimator designs in infinite dimension. Within this context, I study the control of partial differential equations (PDEs) of mixed type, underactuated PDE systems, and delay phenomena. A large part of my research work involves showing well-posedness for the companion kernel PDE, typically a nonlocal Goursat problem and/or PDEs of mixed type with nonlocal coupling.

Other interests are: optimal control, convex optimization, model predictive control, signal processing, and operator theory.

Publications

• S. Chen, R. Vazquez, M. Krstic. Bilateral Boundary Control Design for a Cascaded Diffusion-ODE System Coupled at an Arbitrary Interior Point. Working paper

• S. Chen, R. Vazquez, M. Krstic. Folding Bilateral Backstepping Output-Feedback Control Design For an Unstable Parabolic PDE. Working paper

• S. Chen, R. Vazquez, M. Krstic. Backstepping boundary control of a 1-D 2 × 2 unstable diffusion-reaction PDE system with distinct input delays. American Control Conference, 2019

• S. Chen, R. Vazquez, M. Krstic. Bilateral boundary backstepping control of a 1-D unstable parabolic PDE via a folding approach. 3rd IFAC Joint Workshop on PDE Control and Distributed Parameter Systems (CPDE/CDPS), 2019

• L. Su, S. Chen, J.M. Wang, M. Krstic. Stabilization of 2 x 2 hyperbolic PDEs with recirculation in the unactuated channel. Currently under review in Automatica

• S. Chen, R. Vazquez, M. Krstic. Backstepping control design for a coupled hyperbolic-parabolic mixed class PDE system. American Control Conference, 2017

• S. Chen, R. Vazquez, M. Krstic. Stabilization of an underactuated coupled transport-wave PDE system. Conference on Decision and Control, 2017

Experience

• Controls Intern at ASML / Cymer

  • 2016/06 – 2016/09

  • Developed a PDE-based online estimation algorithm for a droplet generator module in EUV light generation machinery.

• Algorithms Intern at Tesla Motors

  • 2012/05 – 2012/08

  • Designed real-time, adaptive model-based charge time prediction algorithms for Li-ion batteries.

  • Designed data analytics modules in Python for the internal diagnostics and data framework.

• Visiting Student Intern at Hong Kong Univ. Of Science & Technology

  • 2010/05 - 2010/08

  • Evaluated, documented, and designed instructional experiments for control of DC servomotor and magnetic levitation systems.

Teaching

• Teaching Assistant at UC San Diego, MAE 281A (Nonlinear Systems)

  • 2018/01 – 2018/03, 2017/01 – 2017/03

• Teaching Assistant at UC Berkeley, EECS 192 (Mechatronics)

  • 2013/01 – 2013/05

  • Outstanding Graduate Student Instructor (GSI) Award, 2013

Education

• Ph.D (in progress), Mechanical Engineering

  • Univ. of Calif., San Diego, 2015 – 2019

  • Powell-Focht Fellowship recipient

• MS, Mechanical Engineering

  • Univ. of Calif., San Diego, 2013 – 2015

• BS, Electrical Engineering and Computer Sciences

  • Univ. of Calif., Berkeley, 2009 – 2013