Research

Research

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This section has not been updated recently, but will be soon (02/2025). Please refer to my Projects page for more recent info.

Active research areas

  • Motion mitigation and spatiotemporal anti-aliasing technique for low-rate imaging modalities to enable wide-area single-pixel bio-imaging for intraoperative use. This includes the development of techniques to accurately track camera pose in real-time, as well as approaches to account for the scan dynamics of galvo-based line scan cameras to account for inter-pixel shifts. Furthermore, to enable bio-imaging on deformable tissue, I am actively researching image-guided techniques to reconstruct tissue geometry and morphology.

  • Online guaranteed long-term reachability computation and viability analysis for systems experiencing impairment (diminishment of control authority, changed dynamics, impairment of sensor readings). In particular, theory that applies directly to complex nonlinear systems is the focus of this research area. Applications to safe autonomous control are currently in development, focusing on notions from viability theory, contraction theory, and differential inclusions; this latter work is a collaboration with Prof.~Eduardo Sontag. This work enables safe adaptive control of systems in cases of rapidly changing dynamics, deliberate introduction of model order reductions, or incorrect/incomplete sensor readings, domains that are not covered by today’s robust adaptive control techniques.

  • Safe adaptive control and identification of partial differential equations (PDEs), with applications to autonomous electrosurgery. The goal is to develop tractable algorithms for model predictive control of PDEs, extending to real-time adaptation with robustness guarantees. This work ties into control of electrosurgical processes, where tissue biophysics are identified in real-time to support autonomous minimally-invasive surgical action. A key thrust here is also the incorporation of novel sensors, including microscopic thermography, near-infrared stereo vision, and tactile sensors to endow autonomous surgical systems with the means of making safe informed decisions. Implications of these techniques are vast, endowing robotic systems with critical feedback mechanisms that are crucial in advancing the field of robot-assisted healthcare in the operating room. This work is performed in tight collaboration with clinicians, including Dr. Richard Berlin, MD, a Level-1 trauma surgeon with the Carle Hospital System, as well as Dr. Pier Giulianotti and Dr. Enrico Benedetti of the Surgical Innovation and Training Lab (SITL) at the University of Illinois at Chicago.

  • Fault detection, identification, and recovery (FDIR) on single- and multi-agent systems with \emph{simultaneous} sensor and actuator faults. This is an ongoing collaboration with the Jet Propulsion Laboratory’s Maritime and Multi-agent Autonomy (347N) group; these results have garnered direct attention from key stakeholders in the Office of the Chief Technologist and the Autonomous Systems Division at JPL.

  • Development of fundamental theory for controlled partial differential-algebraic equations (PDAEs) and hybrid partial differential equations, with the goal of developing unified theory for real-time robust adaptive control of this class of systems.

Publications

Peer-reviewed publications

Journal Papers

  • B. Petrus*, Z. Chen*, H. El-Kebir*, J. Bentsman, and B.G. Thomas, “Solid Boundary Output Feedback Control of The Stefan Problem: The Enthalpy Approach,” IEEE Transactions on Automatic Control, 2021. Revised version submitted for publication.

  • H. El-Kebir and Melkior Ornik, “Online Guaranteed Reachable Set Approximation for Systems with Changed Dynamics and Control Authority,” IEEE Transactions on Automatic Control, 2021. Submitted for review.

  • S. Zhang, J. Bentsman, X. Lou, C. Neuschaefer, Y. Lee, and H. El-Kebir, “Multiresolution GPC-Structured Control of a Single-Loop Cold-Flow Chemical Looping Testbed,” Energies, vol. 13, p. 1759, Apr. 2020. https://doi.org/10.3390/en13071759 (open access).

  • H. El-Kebir, M.C. Mazza, and J.C.M. Liu, “Perceptions of Open Innovation at CERN: An Explorative Study,” CERN IdeaSquare Journal of Experimental Innovation, vol. 3, pp. 57–61, 2019. https://doi.org/10.23726/cij.2019.945 (open access).

* Shared co-first authorship.

Conference Papers

  • H. El-Kebir*, T. Shafa*, A. Purushottam, M. Ornik, and A. Soylemezoglu, “High-Frequency Vibration Reduction for Unmanned Ground Vehicles on Unstructured Terrain,” in Proc. of 2021 Modelling & Simulation of Autonomous Systems (MESAS'21) Conference, 2021. To appear in print. (open access)

  • H. El-Kebir, Y. Lee, R. Berlin, E. Benedetti, P. C. Giulianotti, L. P. Chamorro, and J. Bentsman, “Online Hypermodel-based Path Planning for Feedback Control of Tissue Denaturation in Electrosurgical Cutting,” in Proc. of 11th IFAC Symposium on Biological and Medical Systems, Ghent, Belgium, 2021. To appear in print. (open access)

  • H. El-Kebir and M. Ornik, “Online Inner Approximation of Reachable Sets of Nonlinear Systems with Diminished Control Authority,” in Proc. of 2021 Conference on Control and Its Applications, (Philadelphia, PA), pp. 9–16, Society for Industrial and Applied Mathematics, 2021. https://doi.org/10.1137/1.9781611976847.2 (open access)

  • H. El-Kebir and J. Bentsman, “PDE-Based Modeling and Non-collocated Feedback Control of Electrosurgical-Probe/Tissue Interaction,” in 2021 American Control Conference (ACC). New Orleans, LA, USA: IEEE, 2021, pp. 4045–4050. https://doi.org/10.23919/ACC50511.2021.9483240 (open access)

* Shared co-first authorship.

Non-peer-reviewed publications

Conference papers

  • El-Kebir, H., & Ornik, M. (2020). In-flight Air Density Estimation and Prediction for Hypersonic Flight Vehicles. In 23rd AIAA International Space Planes and Hypersonic Systems and Technologies Conference. https://doi.org/10.2514/6.2020-2412 (open access)

Coverage

2021

Our achievements in the NASA LEAPFROG challenge were showcased by the Department of Aerospace Engineering at UIUC: Illinois team wins NASA’s LEAPFROG challenge.

2020

My research on in-flight air density estimation was featured by the Department of Aerospace Engineering at UIUC: Predicting in-flight air density for more accurate landing | Aerospace at Illinois.

Talks

CSLSC21

I gave a talk on my research on online guaranteed reachability reachable computation at the University of Illinois’ Coordinated Science Laboratory Student Conference 2021, during the Optimization, Control, and Reinforcement Learning Technical Session held on February 24, 2021:

The slides can be accessed here . A simple code example of the approach presented can be found on Github here .

  • Languages English