At First Light: Expressive Lights in Support of Drone-Initiated Communication

Drones are increasingly used in situations where they can assist a person. However, people are not familiar with drones approaching them. We propose an expressive light system embedded on a drone to convey its intention to initiate communication, which we present as a four-stage process: Drone-Initiated Engagement Model (DIEM). We then describe the design and development of an LED-based prototype divided in two configurations with a total of 26 light animations, and report their evaluation in an online survey (N = 156). We describe the suitability of different configurations, animations, and colors to convey each stage of DIEM. We finally validate our system in a user study (N = 45) that showed that participants can perceive all four stages of approach via the drone movement and that expressive lights provide a more nuanced user experience. We contribute insights into the design of expressive light systems, as a stepping stone towards machine-initiated communication.