  In robotics, understanding human interaction with autonomous systems is
crucial for enhancing collaborative technologies. We focus on human-swarm
interaction (HSI), exploring how differently sized groups of active robots
affect operators' cognitive and perceptual reactions over different durations.
We analyze the impact of different numbers of active robots within a 15-robot
swarm on operators' time perception, emotional state, flow experience, and task
difficulty perception. Our findings indicate that managing multiple active
robots when compared to one active robot significantly alters time perception
and flow experience, leading to a faster passage of time and increased flow.
More active robots and extended durations cause increased emotional arousal and
perceived task difficulty, highlighting the interaction between robot the
number of active robots and human cognitive processes. These insights inform
the creation of intuitive human-swarm interfaces and aid in developing swarm
robotic systems aligned with human cognitive structures, enhancing human-robot
collaboration.
