Unmanned aerial-aquatic vehicles (UAAVs) have the potential to dramatically improve remote access of underwater environments. In particular, fixed-wing UAAVs offer a promising means of enabling efficient locomotion in both aerial and aquatic domains through the use of a lifting surface. In this talk, I will present our approach for enabling multi-domain mobility with a small fixed-wing UAAV consisting of a single-propeller and a delta-wing planform. To this end, I will describe how our approach, which relies almost entirely on commercial off-the-shelf (COTs) components, uses feedback control and optimal trajectory design to solve the water-exit problem. I will demonstrate, through both simulation and hardware experiments, that our approach is indeed feasible, and that it has the potential to offer a robust, low-cost solution for enabling mobility in and across the air and water domains.
Dr. Joseph Moore is a member of the Senior Professional Staff at the Johns Hopkins University Applied Physics Lab (JHU/APL). In 2014, he received his Ph.D. in Mechanical Engineering from the Massachusetts Institute of Technology, where he was a Graduate Research Assistant in the Robot Locomotion Group and developed control algorithms for robust post-stall perching with a fixed-wing unmanned aerial vehicle (UAV). He also holds a B.S. in both Mechanical and Electrical Engineering from Rensselaer Polytechnic Institute. While at JHU/APL, Dr. Moore has continued to develop control algorithms for enabling agile flight with fixed-wing UAVs. He has also worked on developing algorithms for control and motion planning of mobile manipulators and heterogeneous multi-robot teams. His current work focuses on extreme short-field landings with fixed-wing UAVs, unmanned aerial-aquatic vehicles (UAAVs), and the development of algorithms for nonlinear model predictive control.
Implementing frequency response using grid-connected inverters is one of the popular alternatives to mitigate the dynamic degradation experienced in low inertia power systems. However, such solution faces several challenges as inverters do not intrinsically possess the natural response to power fluctuations that synchronous generators have. Thus, to synthetically generate “virtual” inertia, inverters need to take frequency measurements, which are usually noisy, and subsequently make changes in the output power, which is therefore delayed. As a result, it is not a priori clear the whether virtual inertia will indeed mitigate the degradation, or some alternative control strategy will be necessary. In this talk, we present a comprehensive analysis and design framework that provides the tools required to answer this question. First, we develop novel stability analysis tools for power systems, which allows for the decentralized design of inverter-based controllers. The method requires that each inverter satisfies a standard H-infinity design requirement that depends on the dynamics of the components and inverters at each bus, and the aggregate susceptance of the transmission lines connected to it. It is robust to network and delay uncertainty, and when no network information is available reduces to the standard passivity condition for stability. Second, by selecting relevant performance outputs and signal norms, we define system-wide performance metrics that explicitly quantify the effect of frequency measurements noise and power disturbances on the overall system performance. Using a novel modal decomposition, we derive closed-form expressions for system performance that explicitly capture the impact of network topology, generator and inverter control parameters, and machine rating heterogeneity. Finally, we leverage this framework to design a new dynamic droop control (iDroop) mechanism for grid-connected inverters that exploits classical lead/lag compensation to outperform standard droop control and virtual inertia alternatives in both joint noise and disturbance mitigation and delay robustness.
Enrique Mallada is an assistant professor of electrical and computer engineering at Johns Hopkins University. Before joining Hopkins in 2016, he was a post-doctoral fellow at the Center for the Mathematics of Information at the California Institute of Technology from 2014 to 2016. He received his ingeniero en telecomunicaciones degree from Universidad ORT, Uruguay, in 2005 and his Ph.D. degree in electrical and computer engineering with a minor in applied mathematics from Cornell University in 2014. Dr. Mallada was awarded the ECE Director’s Ph.D. Thesis Research Award for his dissertation in 2014, the Cornell University’s Jacobs Fellowship in 2011 and the Organization of American States scholarship from 2008 to 2010. His research interests lie in the areas of control, networked dynamics, and optimization, with applications to engineering networks such as power systems and the Internet.
The Laboratory for Computational Sensing and Robotics will highlight its elite robotics students and showcase cutting-edge research projects in areas that include Medical Robotics, Extreme Environments Robotics, Human-Machine Systems for Manufacturing, BioRobotics and more. JHU Robotics Industry Day will take place from 8 a.m. to 3 p.m. in Hackerman Hall on the Homewood Campus at Johns Hopkins University.
Robotics Industry Day will provide top companies and organizations in the private and public sectors with access to the LCSR’s forward-thinking, solution-driven students. The event will also serve as an informal opportunity to explore university-industry partnerships.
You will experience dynamic presentations and discussions, observe live demonstrations, and participate in speed networking sessions that afford you the opportunity to meet Johns Hopkins most talented robotics students before they graduate.
Please contact Ashley Moriarty if you have any questions.
Please contact Ashley Moriarty if you have any questions.