ESL helps ODOT monitor traffic and roadway conditions from the air
Technology always has a way of moving forward when there is a need.
As drone numbers soar, DriveOhio’s unmanned aircraft systems (UAS) Center is investing $5.9 million for a three-year study on how to safely fit UAS into an already congested airspace (click here to read more about the study). Led by The Ohio State University College of Engineering, the research looks at both air and ground vehicles to complement DriveOhio’s current initiatives in autonomous and connected vehicle testing.
A key component of this research is being conducted at The Ohio State University ElectroScience Laboratory (ESL).
Electrical and Computer Engineering Research Assistant Professor Graeme Smith’s team will oversee ESL’s contribution to the project. “Whether we like it or not, the drones are coming,” Smith said. “Widespread UAS use is going to happen at some point, and it’s exciting that Ohio State is involved in defining how.”
ESL researchers will develop passive radar systems in support of the DriveOhio project to extend the 33 Smart Mobility Corridor capabilities through the use of UAS--sometimes called drones--to monitor traffic and roadway conditions from the air. The inclusion of passive radar in the project represents a major technological advancement that, despite it’s long history, has rarely been used outside of research.
Smith will lead ESL’s contribution to the overall project which includes measuring commercial UAS to understand how they appear to radar, and developing two passive radars to be integrated into the final UAS Traffic Management (UTM) system that will be developed through the initiative.
Smith’s co-investigators at ESL include Professor Chi-Chih Chen who will oversee antenna design for the passive radar, and research scientist Dr. Andrew O’Brien who will lead the development of beamforming algorithms to determine the bearings to the detected UAS.
Unlike optical systems, the size, shape, construction material, and moving parts of the UAS has a significant impact on how easy it is for the radar to detect its presence. For the passive radars being developed at ESL, the electromagnetic frequencies used and the radar-target geometries employed will be different than in traditional air traffic control networks which use active radar.
To better understand the passive radar design requirements, the ESL team will measure commercial UAS, such as the common DJI Phantom, in ESL’s Compact Range--a dedicated facility used to measure object electromagnetic reflectivity and antenna patterns.
“There has been much speculation in the academic community on just what a UAS will look like to a radar. With the work being done on this project we will finally know the answer,” Smith observed.
The ESL team’s principal task will be to develop and evaluate the passive radars' performance within the overall UTM system. The passive radars will detect and track UAS using ambient electromagnetic signals. Their outputs will be combined with the data from a Gryphon Skylight UTM system, which uses active radars and spectral monitoring nodes. By using the passive radars alongside the more conventional sensors, the team will be able to understand the passive radars’ performances and fine-tune their use within the overall solution.
“Passive radar is exciting for this type of task because it doesn’t have its own transmitter. This means that the extra sensors required to provide UAS UTM system will not contribute to the problem of spectral congestion,” Smith said. “It also means the sensors we’re developing are expected to be much cheaper than a conventional active radar. Therefore, you can have more of them and achieve better coverage for tasks such as detecting and tracking UAS.”
In addition to ESL, other research partners for the DriveOhio overall project include The Ohio State University Aerospace Research Center, CAL Analytics, Gannett Fleming, AiRXOS (a GE Venture), SRC, Inc., Transportation Research Center, Inc., Woolpert, The Ohio State University Airport, and Midwest Air Traffic Control.