Administration

Kamran Mohseni

Professor Kamran Mohseni received his B.S. degree from the University of Science and Technology, Tehran, Iran, his M.S. degree in Aeronautics and Applied Mathematics from the Imperial College of Science, Technology and Medicine, London, U.K., and his Ph.D. degree from the California Institute of Technology (Caltech), Pasadena, CA, USA, in 2000.

He was a Postdoctoral Fellow in Control and Dynamical Systems at Caltech for almost a year. In 2001, he joined the Department of Aerospace Engineering Sciences, University of Colorado at Boulder. In 2011, he joined the University of Florida, Gainesville, FL, USA as the W.P. Bushnell Endowed Chaired Professor in the Department of Electrical and Computer Engineering and the Department of Mechanical and Aerospace Engineering. He is the Director of the Institue for Networked Autonomous Systems.


Post-doctoral Researchers

Dr. Mike Krieg

PERC Barbican

Mike primarily studies unconventional underwater propulsion, inspired by squid and other cephalopods, for use on unmanned underwater vehicles. This research focuses on jet formation and vortex ring dynamics, as they relate to propulsive performance. His research is mostly experimental, but he also investigates unsteady propulsion and analytical optimization.

References:
  • M. Krieg and K. Mohseni, Pressure and work analysis of unsteady, deformable, axisymmetric, jet producing cavity bodies, J. Fluid Mech. 769, 337-368, 2015.
  • M. Krieg and K. Mohseni, Synthetic Jets: Fundamentals and Applications, ch. Application of Zero-Net Mass-Flux Actuators for Propulsion: Biology and Engineering, pp329-355, ISBN 9781439868102, CRC Press, 2014

Dr. Adam DeVoria

Hydrodynamics of Micro-flows

Digital fluid dynamics is defined as the creation and manipulation of discrete packets of fluid, such as droplets. When the physical length scales are at the micro-scale, the advantages of employing discrete droplets for applications become increasingly apparent, as surface tension forces dominate allowing for less energetic actuation methods. This experimental research is primarily concerned with understanding the flow inside micro-droplets and how it is affected by parameters such as droplet aspect ratio, Reynolds number, and contact angle.

Low-aspect-ratio wing aerodynamics

This research focuses on investigating the unique aerodynamics and flow-structure interactions of low-aspect-ratio wings. These wings are able to affect reattached flow at high angles of attack, which allows for continued lift generation at these incidences. The downwash induced by the tip vortex flow is crucial in maintaining the reattached flow. Thus the unsteady interaction of the tip vortices with other flow structures, such as the leading-edge shear layer, is very important to the understanding of how to maintain stable flight.

References:
  • A.C. DeVoria and K. Mohseni, Droplets in an axisymmetric microtube: effects of aspect ratio and fluid interfaces, Physics of Fluids, 27(1), 012002, 2015
  • A.C. DeVoria and K. Mohseni, On the mechanism of high-incidence lift generation for steadily translating low-aspect-ratio wings, Journal of Fluid Mechanics, 2017

Dr. Peter Zhang

Department of Mechanical & Aerospace Engineering
Hydrodynamics of irregular multiphase flows

My research focuses on singular interfacial flows and their effect on the transport of mass, momentum, and energy. Interfacial flows are often small in scale and characterized by rapid gradients. This leads to the formation of unique singular fluid flows (moving contact lines, interfacial cusps, etc.) that exhibit a wide range of fascinating dynamics that are fundamentally important to applications like industrial coating, multiphase heat transfer, ink-jet printing, lab-on-a-chip diagnostics, etc. In my research I seek to understand these multiphase irregularities using integrable singularities which conserve fundamental quantities like mass, momentum, and energy without resolving the microscopic phenomena. In this approach, continuum models are capable of capturing the multiscale dynamics of multiphase irregularities. My other research interests include multiphase vorticity dynamics and heat transfer.

References:
  • P. Zhang and K. Mohseni, Theoretical model of a finite force at the moving contact line, under review at International Journal of Multiphase Flow, 2018. preprint available at arXiv:1711.05653.
  • P. Zhang and K. Mohseni, A viscous drag force model for dynamic Wilhelmy plate experiments, under review at Physical Review Fluids, 2018.
  • P. Zhang and K. Mohseni, Dipole model of vorticity at the moving contact line, International Journal of Multiphase Flow, 2018.
  • P. Zhang and K. Mohseni, A unified model for digitized heat transfer in a microchannel, International Journal of Heat and Mass Transfer, 78, 393-407, 2014.

Dr. Bahman Aboulhasanzadeh

Development of Observable Methods for Computational Fluid Dynamics

For the past four decades, Computational Fluid Dynamics community has been developing a variety of methods to compute flows involving material interfaces (multiphase/multi-fluid flow), sharp flow variations (i.e. shocks), and turbulence. While the challenges in these categories of problems look different, they are all the result of limited resolution (Observability Limit) in calculations. By deriving governing equations with the assumption of limited resolution (Observable Set of Governing Equations), we are able to provide a unified framework for correctly computing the material interface, shock, and turbulence.


Graduate Students

Joseph Thalakkottor

Department of Mechanical & Aerospace Engineering
Boundary condition at multiphase contact line

Interface are ubiquitous in nature. The most common boundary condition to define tangential momentum transfer across an interface is the no-slip boundary condition. Although this has been remarkably successful in reproducing the characteristics of many types of flow, it breaksdowns for problems usch as spreading of a droplet, corner flow and extrusion of ploymer melts. Since the breakdown occurs at molecular sclaes, my research focuses on using molecular dynamics simulations to study this breakdown and develop a universal boundary condition for velcoity at the interface. Recent research has dealt with the studying the effect of unsteady flow on slip at the wall in a single phase fluid using molecular dynamic simulations. The left figure shows molecular dynamic simulation of oscillatory Couette flow and the right figure shows the hysteresis observed when slip velocity is plotted against shear rate of fluid.

References:
  • J.J. Thalakkottor and K. Mohseni, Stress dependent slip boundary condition for single and two phase fluid flow on a substrate, 43rd AIAA Aerospace Science Meeting, Kissimmee, FL, 5 - 9 Jan, 2015
  • J.J. Thalakkottor and K. Mohseni, Analysis of Boundary Slip in a Flow with an Oscillating Wall, Physical Review E., 87, 033018, 2013.

Zhuoyuan Song

Department of Mechanical & Aerospace Engineering
Cooperative localization and robot swarm collaboration

This study focuses on cooperative localization methods for autonomous vehicles when the GPS is not easily accessible and the vehicle dynamics is dominated by strong background flow fields. In non-uniform vector fields, path-independent, background vector field based global localization methods are developed to improve the dead-reckoning location estimation (Left). A cooperative localization hierarchy can further improve the overall localization performance in a vehicle swarm through range and frequency limited intra-vehicle measurements and communication (Right).

References:
  • Z. Song and K. Mohseni, Hierarchical underwater localization in dominating background flow fields, IEEE/RSJ Int. Conf. on Intelligent Robots and Systems (IROS 2013) , 3356-3361. Tokyo, Japan, 3-8 November 2013.

Richard O'Donnell

Department of Mechanical & Aerospace Engineering
Applications of Micro Aerial Vehicles

Recent investigations into the flight mechanics of Micro Aerial Vehicles (MAVs) have shown new stability modes that must be incorporated in Low Aspect Ratio (LAR) vehicle design.Using a regime of wind tunnel testing, flow visualization and flight validation I am working to develop an understanding the flight mechanics of MAVs. The understanding of the vehicle class will allow designs to be generated for use in varying applications without the mission specific empirical data currently required in MAV design. I hope this work will ultimately lead to MAVs used to collect data in severe weather systems such as hurricanes.


Matthew Silic

Department of Mechanical & Aerospace Engineering
Control of UAVs

My research focuses on the design and implementation of low-resource autopilots for UAVs, with an emphasis on novel control schemes and collaborative control.


Thomas Linehan

Department of Mechanical & Aerospace Engineering
Aerodynamics and stability of low-aspect-ratio winged fliers

My research draws connections between the fluid dynamics and stability of low-aspect-ratio vehicles. Currently, my focus is on asymmetric flight at incidence angles involving separated flow in which vorticity no longer stays bound to the wing. The consequence of this flow-field is that the aerodynamics and stability properties of the wing become highly non-linear in ways not captured by current modeling strategies.

Publications:
  • T. Linehan and K. Mohseni, Investigation of a sliding alula for control augmentation of lifting surfaces at high angles of attack, Aerospace Science and Technology Journal, under review, 2019.
  • T. Linehan and K. Mohseni, Theoretical prediction of roll moment due to sideslip for thin low-aspect-ratio wings, AIAA Journal, In Press, 2018.
  • T. Linehan and K. Mohseni, Leading-edge flow reattachment and the lateral static stability of low-aspect-ratio rectangular wings, Physical Review Fluids, 2(11):23, 2017.

Andrew Bingler

Department of Electrical & Computer Engineering
Design of Autopilot Hardware

My work includes the design, development, and maintenance of the hardware used for the data collection, control, and telemetry of Micro Aerial Vehicles (MAVs). This hardware is also expandable, allowing it to be modified for use with other UAVs and vehicles.


Kevin Nelson

Department of Electrical & Computer Engineering
Bioinspired multimodel; fish lateral line sensory system

My research focuses on finding a general theory for ideal sensor placement to detect a distributed actuation. One application is to the artificial lateral line we implement for sensing and control in our autonomous underwater vehicle. Experimentally, I have been assisting with the test setup to validate the artificial lateral line.


Yujendra Mitikiri

Department of Mechanical & Aerospace Engineering
Autonomous micro aerial vehicle

Research Interests: Dynamics, Control and estimation methods in fixed-wing UAVs; Geometric and Nonlinear methods; Analog circuits.

Publications:

  • Y. Mitikiri and K. Mohseni, Globally stable attitude control of a fixed-wing rudderless UAV using subspace projection, IEEE RA-Letters, 4(2), 1395-1401, 2019. DOI: 10.1109/LRA.2019.2895889 PDF
  • Y. Mitikiri and K. Mohseni, Measurement noise and gyro bias compensation in geometric attitude estimation, IEEE Int. Conf. on Robotics and Automation (ICRA 2019), Montreal, 20 May - 24 May, 2019.
  • Y. Mitikiri and K. Mohseni, Analytic solutions to two quaternion attitude estimation problems, arXiv 1901.08905v2, 2019. PDF
  • Y. Mitikiri and K. Mohseni, Attitude control of micro/mini aerial vehicles and estimation of aerodynamic angles formulated as parametric uncertainties, IEEE RA-Letters, 3(3), 2063-2070, 2018. PDF

Majid Allahyari

Department of Mechanical & Aerospace Engineering
Application of Observable Methods to large scale simulation

Nicholas Sholl

Department of Mechanical & Aerospace Engineering
Design and control of bioinspired soft actuators

My research focuses on novel design and fabrication techniques that enhance the utility and controllability of soft actuators for use in practical systems.


Austin Moss

Department of Mechanical & Aerospace Engineering
Soft robotics and soft composite mechanics


Alumni