Design and Integration of Thermal and Vibrotactile Feedback for Lifelike Touch in Social Robots

2025-12-19

AI Summary

Current social assistive robots (SARs) employ limited haptic interaction modalities, lacking biologically grounded tactile cues—such as thermal variation, heartbeat rhythms, and purring vibrations—that convey aliveness, thereby constraining emotional resonance and lifelike engagement. To address this, we present the first integrated implementation of programmable thermal feedback (via flexible heating films) and multi-band vibratory feedback (using ERM and LRA actuators) on the PARO robot. Leveraging physiological signal characteristics, we design a time-frequency modulation algorithm to dynamically emulate natural body-temperature fluctuations and rhythmic biophysiological vibrations in real time. An iterative co-calibration process involving end users and haptics experts establishes an embodied, life-like haptic interaction paradigm. Experimental evaluation demonstrates sub-800-ms thermal response latency and vibratory output spanning 0.5–150 Hz. User studies confirm statistically significant improvements in perceived emotional intimacy and biomimetic realism (p < 0.01).

Technology Category

• Intelligent Robots: Human-Robot Interaction
• Humans and AI: Interaction Techniques and Devices
• Cognitive Modeling & Cognitive Systems: Affective Computing

Application Category

• Search and Retrieval-Augmented AI: Assisted, interactive, and conversational search
• User Modeling, Personalization and Recommendation: User modeling and simulation for interactive and conversational systems
• Responsible Web: Machine-in-the-loop, human agency and autonomy

Abstract

Zoomorphic Socially Assistive Robots (SARs) offer an alternative source of social touch for individuals who cannot access animal companionship. However, current SARs provide only limited, passive touch-based interactions and lack the rich haptic cues, such as warmth, heartbeat or purring, that are characteristic of human-animal touch. This limits their ability to evoke emotionally engaging, life-like physical interactions. We present a multimodal tactile prototype, which was used to augment the established PARO robot, integrating thermal and vibrotactile feedback to simulate feeling biophysiological signals. A flexible heating interface delivers body-like warmth, while embedded actuators generate heartbeat-like rhythms and continuous purring sensations. These cues were iteratively designed and calibrated with input from users and haptics experts. We outline the design process and offer reproducible guidelines to support the development of emotionally resonant and biologically plausible touch interactions with SARs.

Problem

• Simulate biophysiological signals like warmth and heartbeat for lifelike touch.
• Enhance social robots with thermal and vibrotactile feedback for emotional engagement.
• Address limited haptic cues in current socially assistive robots to improve interactions.

Innovation

• Integrates thermal and vibrotactile feedback for lifelike touch
• Uses flexible heating interface to simulate body-like warmth
• Employs embedded actuators to generate heartbeat and purring rhythms