Cadets Gain Skills Building Advanced UAVs

Cadets and faculty working in the Intelligent Robotics Laboratory in the Colorado Springs, CO-based USAF Academy Department of Electrical And Computer Engineering here are designing and building more the next generation of sophisticated autonomous unmanned aerial vehicles -- UAVs that will even be able to communicate with each other, working to search, track, and destroy targets as a team.

Another type will be able to hover in place.

The department is working on two separate, but interdependent, projects to develop a distributed network for a set of UAVs. For the first project, six cadets majoring in electrical engineering, computer engineering and system engineering management are working with faculty to build an air-to-air UAV communication network as their capstone senior design project.

The ongoing project, an extension of work done last year, is sponsored by the Air Force Office of Scientific Research. The research team must design, build and test a system network comprised of one ground tracking station and three UAVs. The system sends and receives telemetry and video data within the network, detecting and capturing targets using controllable sensor systems, and displays multiple video images on a ground tracking station screen.

"Decisions have to be made based on contradicting factors," said Dr. Daniel Pack, engineering professor. "Right now we’re focusing our efforts on the issues related to the system design before we build and test a prototype this spring."

The network must allow all three UAVs to communicate with the ground tracking station, while also allowing each UAV to communicate with each other -- independent of the ground control. Bandwidth usage is only one of several considerations cadets have to account for as they make engineering decisions.

“The challenge is to have three video feeds transmitted simultaneously within the network using a limited bandwidth,” said Pack.

While the system linking the multiple UAVs is still compromised by available bandwidth, it will still allow the units to cover a larger operation area away from the ground tracking station. Cadets are currently working on the communication system analysis portion of the project, to determine the best video signal they can expect to send in a realistic case without destabilizing the network.

They are also working to improve the performance of an onboard camera sensor system. Cadets have even designed their own gimbal that allows the onboard camera in three dimensions -- reducing the need to fly the UAV over a target many times at different flight attitudes.

In general, compared to a single sophisticated UAV, a set can complete a task faster, collect more relevant data, more accurately sense the environment, provide redundancy -- if one UAV fails, the group can compensate -- and offer alternatives.

In many military applications, multiple UAVs are necessary to perform the required tasks, such as providing the close coverage of a large area and the capability to engage in multiple mission-critical activities at the same time. Such tasks are not feasible for a single system, no matter how powerful the system may be, Pack said.

The relatively low sophistication involved in creating a set of UAVs, compared to one complex UAV, makes multiple cooperative UAVs more attractive to researchers and operators, he added.

Cadets working on the earlier stage of the project last year successively built three mobile robots that could cooperatively detect and destroy a simulated target. The next step is to successfully complete the same demonstration with UAVs in flight.

For the third project, four cadets with mentors from electrical and computer engineering and the aeronautics departments are working to design a hovering UAV in the senior capstone design course.

The aeronautics department delivered the platform for the vehicle. Engineering cadets are working toward a final flying system with onboard control electronic components that can autonomously lift, land and control its flight while avoiding obstacles.

Last year’s prototype was able to fly for several seconds before it spun out of control and went down.

The military is interested in the possibility of replacing human intelligence with hovering UAVs. A hovering UAV can conduct close surveillance on a specific area for long periods of time.

Unlike a standard UAV, a hovering UAV could conceivably perch on a tree or a building, continuously collecting important data. The success of these projects can directly impact future Air Force use of UAVs, officials said.

(Aero-News salutes Eddie Kovsky, USAFA Public Affairs)

FMI: www.usafa.af.mil