Ti-Chung Lee

About

Ti-Chung Lee is a leading figure in nonlinear control theory, with a career dedicated to solving fundamental challenges in robotic systems and time-varying dynamics. His most impactful work addresses the tracking control of unicycle-modeled mobile robots under input saturation constraints, a problem of critical importance for real-world autonomous navigation. By ingeniously combining the backstepping technique with LaSalle’s invariance principle, Lee’s 2001 paper on saturation feedback controllers has garnered 383 citations, establishing a global solution that remains a cornerstone in the field. Beyond mobile robotics, Lee has made seminal contributions to adaptive and robust control, notably developing an H∞ tracking performance framework for robotic systems and pioneering a general invariance principle for nonlinear time-varying systems. His 2001 work on this principle, with 43 citations, provides an elegant output-to-state criterion using integral inequalities, extending classical stability analysis to non-periodic systems. Lee also advanced the practical control of flexible-joint manipulators using only position measurements, a significant achievement for sensor-limited applications. With a portfolio of highly cited papers spanning from 1996 to 2004, Lee’s research continues to influence modern control design, offering rigorous, implementable solutions that bridge theory and application.

Research Focus

Key Achievements

Top Papers

1. 1
   Tracking control of unicycle-modeled mobile robots using a saturation feedback controller

   383 citations · 2001
2. 2
   Adaptive control in robotic systems with H∞ tracking performance

   67 citations · 1997
3. 3
   A general invariance principle for nonlinear time-varying systems and its applications

   43 citations · 2001
4. 4
   Tracking control of flexible joint manipulators using only position measurements

   34 citations · 1996
5. 5
   A general stability criterion for time-varying systems using a modified detectability condition

   22 citations · 2002
6. 6
   Tracking control of mobile robots using saturation feedback controller

   20 citations · 2003
7. 7
   Adaptive control of robots by linear time-varying dynamic position feedback

   11 citations · 1996
8. 8
   Practical stabilization for nonholonomic chained systems with fast convergence, pole-placement and robustness

   9 citations · 2003
9. 9
   A motion planning approach to fast parking control of mobile robots

   4 citations · 2004
10. 10
    Adaptive tracking control of nonholonomic mobile robots by computed torque

    2 citations · 2003

Key Collaborators

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