  Human-to-human communications are enriched with affects and emotions,
conveyed, and perceived through both verbal and nonverbal communication. It is
our thesis that drone swarms can be used to communicate information enriched
with effects via nonverbal channels: guiding, generally interacting with, or
warning a human audience via their pattern of motions or behavior. And
furthermore that this approach has unique advantages such as flexibility and
mobility over other forms of user interface.
  In this paper, we present a user study to understand how human participants
perceived and interpreted swarm behaviors of micro-drone Crazyflie quadcopters
flying three different flight formations to bridge the psychological gap
between front-end technologies (drones) and the human observers' emotional
perceptions. We ask the question whether a human observer would in fact
consider a swarm of drones in their immediate vicinity to be nonthreatening
enough to be a vehicle for communication, and whether a human would intuit some
communication from the swarm behavior, despite the lack of verbal or written
language.
  Our results show that there is statistically significant support for the
thesis that a human participant is open to interpreting the motion of drones as
having intent and to potentially interpret their motion as communication. This
supports the potential use of drone swarms as a communication resource,
emergency guidance situations, policing of public events, tour guidance, etc.
