I. INTRODUCTION
Robotic swarms are made up of small, homogeneous robots with limited capabilities that act through local interactions to collectively achieve a variety of behaviors including flocking [1], [2], [3], [4], deployment [5], [6], and foraging [7], [8]. The principal advantage of swarms is that, due to their large numbers and emergent behaviors, they are typically robust to failure of individual robots. For using swarm robotic systems in human-supervised missions, it is imperative to understand the basic tenets of human-swarm interaction (HSI) [9]. Key characteristics of swarm robotic systems that make HSI challenging are (a) the swarm behavior is self-stabilizing and takes some time to emerge (b) individual robots in a swarm are very simple units with limited communication hardware capabilities and (c) robots have poor localization capabilities leading to errors in interpreting the input of the operator. The communication latency and the input error along with the self-stabilizing nature of the emergent behaviors of robotic swarms create challenges for the operator in understanding the current state of the swarm and the effect of his or her command.