News Feature | January 16, 2018

Pentagon Wants Wirelessly Powered Drones That Mimic Animal Flight, Metamaterial-Based Antennas

By Jof Enriquez, Follow me on Twitter @jofenriq

The U.S. Department of Defense (DoD) is inviting industry and university-based collaborative teams to apply for grants to develop for the Air Force a new generation of drones and aircraft that copy the flight mechanics of insects and bats, and which draw power wirelessly at great distances.

Under the new pilot program, Defense Enterprise Science Initiative (DESI), applicants are to focus on flight technologies that enable "a new generation of sensing, mobility, and autonomy." In particular, research topics for the FY 2018 program are identified as: power beaming, highly maneuverable autonomous unmanned aerial vehicles, soft active composites, and metamaterial-based antennas.

Research managers at the Air Force Office of Scientific Research (AFOSR) enjoin scientists to develop highly-maneuverable, fully-autonomous drones that mimic nature (biomimetic), and whose flight capabilities exceed those of traditional quadcopter or fixed wing designs. In other words, they want next-generation drones that don't look or act like drones to the enemy.

"The biological study of agile organisms such as bats and flying insects has yielded new insights into complex flight kinematics of systems with a large number of degrees of freedom, and the use of multi-functional flight surface materials," the grants notice states.

While biomimetic designs for designs for crawling, slinking and swimming robots go back decades, the far more complex mechanics of animal flight so far have limited the military’s smallest drones to conventional aerodynamic designs, noted Defense One.

In order to design drones with the agility and dexterity that rival biological systems, DoD says robotic systems require breakthrough components, such as soft active composites and novel 3D materials (e.g., active liquid-crystal elastomers, liquid metals, hyperelastic light-emitting capacitors, next-generation shape memory alloys/polymers, etc.), featuring locally tunable material properties with embedded sensing and actuation.

Flexible-wing drones do exist today, but powering up these machines wirelessly remains a challenge.

For power beaming, besides solar power, DoD says "wireless power transmission could augment existing technologies and enable new paradigms for warfighter operations in denied environments, unmanned or autonomous surveillance and weapons systems." It then suggests "innovative power transmission modalities using laser, microwave or other electromagnetic frequencies" and the use of metamaterials, as possible ways to power UAVs wirelessly, extending their range and endurance.

The Pentagon wants university-industry teams to research new microwave/millimeter wave airborne antenna concepts based on metamaterial elements. It also encourages researchers to build off Air Force scientists’ existing research on replacing parabolic and phased-array antennas with metamaterial-based flat antennas that have a reduced profile, increased throughput, and no moving parts.

Specifically, participating teams should look into reducing the aerodynamic footprint of UAVs by embedding antennas into the surface of the aircraft, or having the antenna conform to the airframe geometry. Also of particular interest is how to increase the speed of communications or surveillance between the aircraft and its surroundings by up to 3 orders of magnitude.

The DESI program aims to accelerate the impact of basic research knowledge on key defense challenges or capability gaps, especially in light of increasing need for drones in conflict areas, and diversifying nuclear drone designs.

DESI will support grantees with approximately $750,000 of funding per year for two years. Approximately four awards of $1.5 million each will be given, for a total amount of $6 million for the program.