• Intuition...
  • ...studying...
  • ...formalizing ideas...
  • ...and veryfing the results

Ongoing Research Projects

Bio-Inspired GNC System for UAVs Moving in Tactical Terrain

In this research, we design a bio-inspired guidance, navigation, and control sytstem for autopilots of multi-rotor Unmanned Aerial Vehicles (UAVs) operating in potentially hostile areas.

Sponsor: DARPA, Collaborator: Dr. Johnson (Penn State University)

Robust Data-Driven Control of UAVs and UAMs

Robust data-driven control for autonomous control of unmanned aerial vehicles (UAVs) and unmanned aerial manipulators (UAMs, aka "flying robots") are created, implemented, and testeded. Our controllers also assist human operators both to fly in cluttered and poorly modeled environments and prevent dangerous maneuvers.

Sponsor: RCTA, Collaborators: Army Research Lab, Dr. Likhachev (Carnegie Mellon University)

Constrained Control Design and UAS

Nonlinear robust control laws for nonlinear dynamical systems subject to constraints on the state, the trajectory tracking error, and the control input are designed. These control laws are tested in simulation and on actual unmanned aerial systems (UAS) such as UAVs and UAMs. Students from multiple departments at OU are involved.

Sponsor: National Science Foundation

Autonomous UAVs Perofrming Shipboard Landing

We design innovative robust adaptive control algorithms that counteract the effects of severe disturbances and unmodeled dynamics. These theoretical results will be applied to design autopilots for multi-rotor UAVs performing shipboard landing. Special emphasis is given to the study of the ground effect and the wake of ships on multi-rotor UAVs in proximity of the landing pad.

Sponsor: Office of Naval Research (ONR), Collaborator: Dr. Walters (The University of Oklahoma)

Aerial robotics

In this research, we pursue the design of guidance, navigation, and control systems for multi-rotor unmanned aerial manipulators (UAMs) equipped with robotic arms to autonomosly find, pickup, manipulate, and deploy objects in unknown environments.

Past Research Projects

UAS and Improved Weather Services

In this research, we designed autopilots for UAS collecting data for improved weather forecasts. We also combined an indirect adaptive control law and an unscented Kalman filter to estimate the wind velocity from the effort needed to hover the vehicle.

Sponsor: NOAA

Optimal Control for Finite-Time Stabilization

It is often desireable to attain finite-time stability of a nonlinear system, that is, converging to a Lyapunov stable equilibrium point in finite time. In this research, we provided sufficient conditions for state- and output-feedback optimal finite-time stabilization. YouTube video.

Differential Games of Nonlinear Dynamical Systems

In this research, we studied two-player differential games whose end-of-game condition is the closed-loop asymptotic, partial-state, or finite-time stability of the closed-loop system despite the evader's input. Connections to robust nonlinear control are explored.

Output-Feedback Sliding Mode Control with Constraints on the State Space

Accounting for recent results in the theory of time-varying finite-time stable dynamical systems, in this reseach we designed sliding mode controls for nonlinear constrained dynamical systems. The proposed control law is effective with any observer.

Optimal Semistabilization of Linear and Nonlinear Dynamical Systems

In this research, we derived state-feedback control laws that minimize a performance measure in integral form and guarantee semistability of the closed-loop system. YouTube Videos: Video 1 and Video 2.