Military researchers ask industry to use climbing robots to create mesh network for jungle communications

May 11, 2021
SQUIRREL seeks to extend the range of wireless mobile communication in triple-canopy tropical rainforest to enable small teams of four to six warfighters.

ARLINGTON, Va. – U.S. military researchers are asking industry to find ways of using small flying or climbing robots to enhance communications in dense, wet tropical jungles by establishing self-positioning 3D mesh communications for small-unit operations.

Officials of the U.S. Defense Advanced Research Projects Agency (DARPA) in Arlington, Va., released a Small Business Innovation Research (SBIR) opportunity on Friday (HR001121S0007-14) for the SQUad Intelligent Robotic Radio Enhancing Links (SQUIRREL) project.

SQUIRREL seeks to extend the range of wireless mobile communication in triple-canopy tropical rainforest to enable small teams of four to six warfighters to communicate easily not only among themselves, but also with battlefield commanders in other locations.

SQUIRREL anticipates using climbing, flying, or hybrids robots as radio relays to form self-positioning three-dimensional mesh communications networks in support of small unit operations such as reconnaissance.

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Good communications for U.S. missions like hostage rescue, scouting, and training allies can be lost in difficult RF environments like jungles and caves, DARPA researchers point out. Small military units operating in triple-canopy jungle face particularly difficult conditions for mobile radio frequency (RF) communication because of attenuation from layers of wet foliage.

Yet it may be possible to form a dense, low size, weight- and power-consumption (SWaP) 3D mesh of radio communications relays that moves with squads of no more than eight members that helps squad members keep in touch, and keep higher-echelon commanders informed of their status.

These robot-assisted 3D mesh communications networks should be easy to deploy; function on long missions; low noise; low observable; and low probability of detection or intercept.

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Small unit movement through a jungle environment means a SQUIRREL mesh must adapt continuously to new settings as it follows and supports the team. To avoid using RF power levels high enough to escape the jungle canopy, SQUIRREL nodes should use low-power RF and free-space optical communications as they move.

SQUIRREL phase-one will develop feasibility studies using reports and white papers based on existing work; test and measurement data; prototype designs; and performance projections. Phase 2 will develop climbing and flying robots with communications relays that weigh less than one pound each.

Some of these robots must include capabilities for locating, self-positioning, and free-space optical means to reach orbiting unmanned aerial vehicles (UAVs) or other overhead assets for reachback communications.

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SQUIRREL also could be useful in public service roles such as search and rescue in densely wooded areas in temperate zones -- particularly in its reachback role. SQUIRREL also could provide commercial communications nodes in dense forests for drug formulation and counting endangered species.

Companies interested should submit proposals to the Defense SBIR/SSTR Innovation website no later than 29 June 2021 at Email questions or concerns to DARPA at [email protected] with BAA number HR001119S0035-20 in the subject line.

More information is online at

About the Author

John Keller | Editor-in-Chief

John Keller is the Editor-in-Chief, Military & Aerospace Electronics Magazine--provides extensive coverage and analysis of enabling electronics and optoelectronic technologies in military, space and commercial aviation applications. John has been a member of the Military & Aerospace Electronics staff since 1989 and chief editor since 1995.

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