Emotion Through Motion: How Shape-Changing Jewelry Conveys Emotions

Paper Title

Emotion Through Motion: How Shape-Changing Jewelry Conveys Emotions

Publication Info

• Topic area: Emotional communication through shape-changing wearable devices.
• Keywords: Shape-changing interfaces, wearable technology, emotional communication, soft robotics, jewelry design, motion parameters, valence, arousal, tactile feedback, human-computer interaction.

Background and Problem

• Problem / challenge: Existing research lacks a detailed understanding of how fundamental parameters of shape change (e.g., motion type, repetition, amplitude, material) influence the emotions conveyed to both wearers and observers. Additionally, the impact of tactile versus visual perception of shape change remains unexplored.
• Significance: Understanding these effects can enable the design of wearable interfaces that communicate emotions more effectively, enhancing interpersonal communication and user experience.
• Motivation and related work: Prior studies have shown that shape-changing objects can communicate emotions, but they often focus on limited parameters or use static objects. Research on wearable shape-changing jewelry as a medium for emotional communication is scarce, particularly regarding the differences between tactile and visual perception.

Solution

• Proposed approach: A shape-changing necklace with pneumatic actuators was developed to systematically study the effects of motion parameters on emotional communication, using Russell’s circumplex model of valence and arousal.
• Novelty:
  1. Systematic investigation of motion parameters (type, repetition, amplitude, material) on emotional valence and arousal.
  2. Comparison of emotional effects between tactile (wearing) and visual (observing) perception of shape change.
  3. Development of a toolkit for designing and fabricating consistent soft robotic actuators.
• Procedure and key techniques:
  • Two user studies were conducted:
    • Study 1: Observers rated emotions conveyed by videos of the necklace actuating.
    • Study 2: Participants rated emotions while wearing the necklace and observing it live.
  • Motion parameters (type, repetition, amplitude, material) were systematically varied.
  • Emotional ratings were collected using Russell’s circumplex model and supplemented with qualitative associations.

Results

• Concrete findings:
  • Symmetrical motions were rated higher in valence and arousal and were identified more accurately.
  • Repetitive motions increased arousal ratings, with high-speed repetitions eliciting higher excitement.
  • Motion type influenced emotional valence (e.g., upward motions were perceived as positive, downward as negative).
  • Amplitude intensified emotional ratings, while material had negligible effects.
  • Wearers misidentified motions in 61.6% of cases but rated their emotional impact similarly to observers.
• Advantage over baselines:
  • Live observations elicited stronger emotional responses than videos, confirming the importance of real-time interaction.
  • The study provided a more detailed categorization of motion parameters than prior work, enabling precise emotional communication.
• Experiments / evaluation:
  • Study 1: 24 participants observed 120 motion conditions (5 motion types × 3 repetitions × 2 amplitudes × 4 materials).
  • Study 2: 30 participants evaluated 80 conditions (10 motion types × 2 repetitions × 2 materials × 2 modalities).
  • Metrics: Valence and arousal ratings, motion identification accuracy, and qualitative associations.
• Limitations and future work:
  • Limited to cuboid-finger actuators; future studies should explore other shapes and faster actuation mechanisms.
  • Did not examine the effects of jewelry color or collect physiological data.
  • Potential fatigue effects in observation conditions; a between-subjects design could address this.

Summary

This study investigated how motion parameters of a shape-changing necklace influence the emotions conveyed to wearers and observers. Symmetrical motions and high-speed repetitions were found to enhance emotional valence and arousal, while material had minimal impact. Wearers often misidentified motions but rated their emotional effects similarly to observers, suggesting a robust tactile-emotional connection. The findings provide actionable design implications for wearable interfaces, emphasizing the use of repetition, symmetry, and gesture-like motions to convey specific emotions. The provided toolkit and supplementary materials support replication and further research into emotional communication through shape-changing wearables.