Tactile regulation with pocket-sized robots: reducing movement and heart rate in children through hand-held interaction.

Periods of heightened arousal or restlessness can interfere with children's ability to remain physically calm in everyday settings such as classrooms. Handheld tactile technologies may offer a simple and engaging way to support brief moments of structured sensory-motor engagement. This paper investigates how a pocket-sized tactile device influences physiological and behavioral markers of calmness in typically developing children. Building on prior work examining heart-rate modulation, we present new findings on how a handheld rhythm-matching interaction affects full-body movement and postural stability. Eighteen children participated in a within-subjects study involving two conditions: active interaction with a handheld tactile rhythm-matching game and a comparison condition in which they held the same device with the tactile interaction disabled. Results showed lower heart rate during active interaction, with an average reduction of 3.37 bpm (p = 0.019), and lower overall body movement, with movement decreasing by 37.6% (p = 0.002). Regional movement analyses showed the largest reductions in head, neck, and shoulder movement (44.8% reduction) and upper-limb movement (48.5% reduction). These findings suggest that brief tactile rhythm-matching interaction with a handheld device is associated with reduced acute physiological arousal and physical restlessness in children. The study provides a preliminary baseline for future work examining how tactile robotic interactions may support calmness in more demanding or stressful contexts.