Designing Task-Induced Arousal: A Multimodal Stress Induction Method for Interactive Experiments

HCI and HRI studies often require short, repeatable arousal manipulations that can run while participants continue interacting with a device or robot. These experiments are often challenged by the need to induce arousal in settings that still resemble real interaction. Participants must continue using a device, touching a robot, or producing sensor data while the manipulation unfolds. We aimed to develop a compact and repeatable way to induce controlled task-related arousal during interactive experiments by combining a lightweight browser-based pacing task, escalating timing demands and urgency cues, and a concurrent physical hotwire-style challenge. In an A-B-A within-participant study, the induction condition significantly increased mental demand, temporal demand, effort, frustration, and SAM arousal (all p < .001), while perceived performance decreased (p < .001). GSR peak rate increased relative to both calm conditions (p = .030) and escalated over time (p < .001). Grip variability also increased (p = .036), as did release speed (both p < .001), while valence remained above the scale midpoint. These results provide initial evidence that the combined procedure induces controlled, relatively high-valence task-related arousal and may serve as a reusable experimental tool for future human-computer and human-robot interaction studies.