The University of Illinois Chicago has received an $8 million award from the Army Research Laboratory, or ARL, to support the development of specialized sensors to enable drones to use different types of fuel. They also will seek to advance hybrid-electric optimization, which has relevance for commercial drones and other vehicle types.
Unmanned aircraft systems -- otherwise known as drones -- are deployed for numerous reasons. In military settings, drones are used to conduct surveillance and deliver needed goods and materials. Drones today operate on jet fuels shipped from a small number of suppliers in the United States.
"The problem with this is that it may be difficult to get needed fuel to remote locations," said Kenneth Brezinsky, professor of mechanical and industrial engineering in the UIC College of Engineering and principal investigator on the project. "Other fuel types, like those that may be more locally available or those that may be found out in the field with unknown properties, may not be usable because drones can't burn them efficiently, or at all."
Brezinsky and co-principal investigator Patrick Lynch, UIC assistant professor of mechanical and industrial engineering, are developing sensor technology under an open research program to identify fuel properties and enable drones to adjust so that they can use these fuels.
Similar to the unleaded gasoline used in automobiles, which comes in a variety of octanes that reflect different ignition and combustion characteristics of the fuel, jet fuel used in drone diesel engines comes with different ignition characteristics that can be denoted by cetane numbers. The cetane number is reflective of the ease of combustibility of the fuel. Higher cetane numbers indicate fuels that ignite more easily than fuels with lower cetane numbers.
However, that's where the similarities end.
"You can't just put different cetane number fuels into drones the way you can fill the tank of your car with different octane number fuel and expect it to run," Brezinsky said. "Currently, drones can only use a very narrow range of fuel types, and the first step to broadening their range is to be able to accurately and quickly identify fuel properties."
The information provided by the sensors will be used to adjust the drone's combustion system so it can safely and efficiently use that particular fuel.
"The more fuels drones are able to use, the longer and farther they will be able to fly," Lynch said.
Brezinsky and Lynch, who are experts in combustion chemistry and the diagnostics of reacting chemical systems, will expand on previous UIC research to build and test their sensors for practical application.
Their prior work in this area provides unique expertise in characterizing fuel properties and determining the efficiency of fuel combustion during flight. They also will use machine learning systems to enable further development of the sensors.
These sensors developed at UIC will combine with models, control strategies, and ignition assistance actuators developed by other university partners and Army Research Laboratory collaborators to enable multi-fuel capability in unmanned aircraft systems.
The funding from the ARL will be provided over the course of four years. Approximately $3 million has been awarded for the first two years, with another $5 million to be awarded in the following two years, pending project outcomes and resources.
The long-term funding provided by ARL creates a unique opportunity for UIC to educate both undergraduate and graduate students in the basic sciences of combustion, sensing, controls and optimization needed for future unmanned aircraft systems propulsion. The partnerships with ARL prepare and motivate the students to enter the workforce as engineers ready to address the challenges of drone systems.
"Collaborative research partnerships between the Army, academia, and industry are crucial to achieving our mission," says ARL Central Regional Lead, Dr. Mark Tschopp. "The University of Illinois Chicago is bringing faculty expertise, unique facilities, and great students in fuel sensing and algorithmic development in a partnership with the Army to advance these technologies and provide future capabilities."
UIC's Hadis Anahideh, research assistant professor, and Pranav Bhounsule, assistant professor, both from the department of mechanical and industrial engineering, are senior personnel on the project.
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