Playing with Robots: Performing Arts Techniques for Designing and Understanding Robot Group Movement

Research Background and Issues

• Identified Problems or Challenges: Current research in human-robot interaction (HRI) and social robotics regarding group robot movement primarily focuses on micro-robots or swarm robots, which are not applicable to quadrupedal bionic robots with advanced movement capabilities. Additionally, robot movement patterns often emphasize anthropomorphic appearance while neglecting the expressive effects of group movement itself. Existing group robot designs are often based on engineers' intuition, which may not align with human perception in real-world scenarios.
• Significance: With the increasing prevalence of quadrupedal bionic robots, their movements in social contexts will influence human feelings of safety, trust, and emotional responses. Furthermore, designing group robot behaviors can promote practical applications of HRI in fields such as education, entertainment, and healthcare.
• Research Motivation: By drawing on theories and experiences from drama and performing arts (e.g., emotional expression, spatial relationships, and body language), new methodologies can be developed for designing group robot behaviors, addressing current deficiencies in this area. This approach has proven effective in designing emotional and movement behaviors for individual robots but has not yet been systematically applied to the design of quadrupedal robot group behaviors.

Solution

• Proposed Methods and Solutions: The authors integrated methods from performing arts to design movement patterns for quadrupedal robot groups and validated these designs through experiments, bridging theory and application. The core solution involved three research steps: observing human group movement patterns, translating these patterns into robot movement designs, and evaluating the impact of these patterns on observers' emotional responses.
• Innovations:
  • Introducing the "Viewpoints" system from performing arts to understand the dynamics of human group movements and mapping these dynamics onto quadrupedal robot groups.
  • Establishing a complete workflow from theatrical interpretation to concrete robot behavior implementation, providing practical application cases for the integration of drama and HRI.
  • Developing 12 movement patterns (e.g., "Gather," "Play") classified into three stages (Meeting, Testing Boundaries, Trust) based on the narrative framework of the "Hero's Journey," enhancing the expressiveness of contextualized design.
• Implementation Steps:
  1. Experiment 1: Observing human group behaviors using theatrical stage grids (3x3 grid) and basic drama exercises (e.g., softening visual focus exercises and social interaction simulations).
  2. Experiment 2: Extracting group behavior patterns from Experiment 1, iteratively designing quadrupedal robot movement sequences using stop-motion animation prototypes, and validating their functionality and expressiveness through actor feedback.
  3. Experiment 3: Testing the final robot group behavior designs in a controlled environment with 20 participants, using the Affect Circumplex model and think-aloud protocols to evaluate the emotional impact of these behaviors on humans.

Research Outcomes

• Specific Results:
  • Design and Implementation: Proposed 12 group movement patterns and their corresponding emotional triggering effects, with naming and structure based on the classic narrative theory of the "Hero's Journey."
  • Emotional Response Analysis: Using the Circumplex Model of Affect, it was found that most movement patterns elicited high emotional valence (positive emotions) and medium-to-high arousal levels.
  • Behavioral Recognition Accuracy: Participants identified 9 movement patterns with accuracy exceeding random guessing expectations, with patterns like "Gather" and "Mirror" correctly recognized by over 80% of participants.
  • Narrative Framework Validation: User feedback indicated that the "Hero's Journey" framework helped establish a dynamic relationship of gradually building trust between humans and robots.
• Advantages Over Existing Solutions:
  • Moving beyond robot movement research centered on individual robots, exploring group dynamics and human cognition of collective behaviors.
  • Systematically applying theatrical inspirations to group robot design, enhancing the richness and recognizability of emotional expression.
• Limitations and Future Directions:
  • Terminology Challenges: Certain terms (e.g., "merge" and "weave") caused comprehension difficulties for non-technical participants; future designs should adopt more intuitive terminology.
  • Synchronization Issues: Fully synchronized movements may evoke "militarization" associations among participants; future work should explore partially synchronized movement patterns to enhance naturalness.
  • Participant Diversity: Current experiments involved participants with strong technical backgrounds; future studies should include more non-technical populations to validate the general applicability of the behaviors.
  • Hardware and Programming Constraints: The quadrupedal robots used in the experiments relied on manual programming without a central control system; future efforts should incorporate more automated measures to optimize behavior design.
  • Real-World Testing: The experimental environment differed significantly from complex, dynamic, uncontrolled real-world settings; the next phase should test the applicability of the designs in practical scenarios.

Conclusion and Significance

Through three progressive experiments, the authors demonstrated how performing arts can provide new perspectives and practical applications for designing group robot behaviors. This integration bridges the gap between theatrical theory and technological implementation in HRI, particularly in guiding human emotions and trust. The proposed design guidelines lay the foundation for enhancing the friendliness and functionality of robots in social environments, offering significant theoretical and practical value.