No Electrical Outlet, No Problem for UMD Robotic Bird That Harvests Solar Energy

Robotic bird's solar cell wings feed on the sun, provide energy for the long haul

COLLEGE PARK, Md., Oct. 8, 2013 /PRNewswire-USNewswire/ -- Small robotic birds are showing lots of promise for tasks such as monitoring the environment and conducting surveillance. But one current drawback they have is the amount of time they are able to stay aloft. Because of the birds' light weight and small size, the tiny batteries used to power them deplete in just a few minutes.

University of Maryland Professors S.K. Gupta and Hugh Bruck and their students in the Maryland Robotics Center are working on a solution that will allow longer flights and battery recharging in remote places without electrical outlets. The Clark School of Engineering team has developed and demonstrated a new version of its Robo Raven micro air vehicle (MAV) that incorporates solar panels in its wings.

While the solar panels do not yet produce enough energy to power Robo Raven III in flight (they produce around 3.6 Watts while Robo Raven needs around 30 Watts to fly), they are effective in charging the MAV's batteries when it is stationary.

Gupta notes that the development team envisions Robo Raven flying "far away from civilizations" during long missions and needing "a way to 'feed' itself" on its journeys.

Because Robo Raven's large wings have enough surface area to create a usable amount of solar energy, the team decided to incorporate flexible solar cells into them. The captured solar energy is then used to supply Robo Raven's onboard batteries.

"These new multi-functional wings will shape the future of robotic birds by enabling them to fly longer, farther, and more independently because they will be getting their power from the sun," says Mechanical Engineering Ph.D. student Luke Roberts, a member of the Robo Raven team.

The underlying material of the flexible solar panels is different from that used in the previous version of Robo Raven. That meant the team needed to design new wings and develop a new additive manufacturing process to fabricate them, Gupta says.

"We still need to make significant improvements in solar cell efficiency and battery energy density to replicate the endurance of real ravens in Robo Raven III," Gupta says. "But the good news is that Robo Raven III has already demonstrated we can fly with a solar cell and battery combination. Now that we've successfully taken this step, swapping new technologies that are more efficient should be relatively simple."

Gupta has been working on flapping-wing robotic birds for the better part of a decade. His team first successfully demonstrated a flapping-wing bird in 2007. Robo Raven, the first flapping-wing MAV with independent, programmable wings, was introduced earlier this spring. Gupta holds a joint appointment in Mechanical Engineering and the Institute for Systems Research, and Bruck is a Mechanical Engineering professor.

This work was funded in part by the Air Force Office of Scientific Research.

To see Robo Raven in action, visit: http://www.youtube.com/umdrobotics

More Information:

S.K. Gupta's blog post about Robo Raven III: unorthodoxideas.blogspot.com
Robo Raven III YouTube video: youtu.be/t1_mPe8Y0V4

More about the Robo Raven: www.isr.umd.edu/news

Maryland Robotics Center YouTube channel: www.youtube.com/umdrobotics
See Robo Raven III at Maryland Robotics Day, October 25: robotics.umd.edu/Md_robo_day

About the A. James Clark School of Engineering
The University of Maryland's A. James Clark School of Engineering is a premier program, ranked among the top 20 in the world. Located just a few miles from Washington, D.C., the Clark School is at the center of a constellation of high-tech companies and federal laboratories, offering students and faculty access to unique professional opportunities.  

Our broad spectrum of academic programs, including the world's only accredited undergraduate fire protection engineering program, is complemented by a vibrant entrepreneurial ecosystem, early hands-on educational experiences, and participation in national and international competitions.

The Clark School is leading research advancements in aerospace, bioengineering, robotics, nanotechnology, disaster resilience, energy and sustainability, and cybersecurity. From the universal product code to satellite radio, SMS text messaging to the implantable insulin pump, our students, faculty, and alumni are engineering life-changing innovations for millions. Learn more at www.eng.umd.edu.

About the University of Maryland
The University of Maryland ranks among the top 20 public research universities in the nation, and is the closest in proximity to the nation's capital. As the state's flagship university, UMD educates the most talented students from Maryland and beyond. For more information, please visit:

The University of Maryland: www.umd.edu
The A. James Clark School of Engineering: www.eng.umd.edu 
The Maryland Robotics Center: robotics.umd.edu 
The Institute for Systems Research: www.isr.umd.edu 
The Department of Mechanical Engineering: enme.umd.edu

SOURCE A. James Clark School of Engineering