Towards Understanding the Design of Shared Bodily Control via Exoskeleton-based Play

Paper Title

Towards Understanding the Design of Shared Bodily Control via Exoskeleton-based Play

Publication Info

• Topic area: Human–machine interaction in bodily-integrated systems.
• Keywords: Shared bodily control, exoskeleton, human–machine interaction, agency, ownership, collaboration, competition, embodied play, design implications.

Background and Problem

• Problem / challenge: Existing research on bodily-integrated systems primarily focuses on movement execution rather than decision-making, leaving unexplored how systems initiating movements with their own logic affect human-machine relationships and bodily experiences.
• Significance: Understanding shared bodily control is crucial for advancing applications in rehabilitation, assistive technologies, and embodied play, where human-machine collaboration can redefine bodily agency and interaction.
• Motivation and related work: Prior work has explored human-machine intertwinement, bodily experience, and relational dynamics, but lacks focus on how users interpret system-initiated movements reflecting autonomous decision-making. This paper addresses this gap by investigating shared control scenarios.

Solution

• Proposed approach: A set of three playful exoskeleton-based game scenarios—Proxy Pong, DualForce Pong, and SyncedWings—designed to explore relational dynamics of proxy, competition, and collaboration in shared bodily control.
• Novelty:
  1. Introduction of an exoskeleton system that initiates bodily movement based on its own internal logic.
  2. Empirical insights into user experiences of shared bodily control through qualitative analysis.
  3. Conceptual design space and implications for designing bodily-integrated systems.
• Procedure and key techniques:
  • Development of an exoskeleton capable of actuating one arm with autonomous decision-making logic.
  • Implementation of three game scenarios to evoke proxy, competitive, and collaborative dynamics.
  • Conducting a qualitative study (N=16) using semi-structured interviews and thematic analysis to explore user experiences.

Results

• Concrete findings:
  • Participants experienced agency loss as frustrating, playful, and reflective, with collaboration preferred over competition by most.
  • Bodily ownership was fluid and contextual, evolving from heightened awareness to perceiving the system-controlled limb as autonomous.
  • Symmetry in movements fostered coordination and immersion, while asymmetry caused disorientation.
  • Ethical concerns emerged around autonomy, safety, and transparency, with calls for clear accountability and design standards.
• Advantage over baselines: The study uniquely highlights experiential dimensions of shared bodily control, emphasizing relational and interpretive dynamics rather than technical performance.
• Experiments / evaluation:
  • Participants played three games with the exoskeleton under proxy, competition, and collaboration modes.
  • Semi-structured interviews explored agency, ownership, system autonomy, and ethical reflections.
  • Inductive thematic analysis identified four experiential themes.
• Limitations and future work:
  • Homogeneous participant demographics limit generalizability; future studies should include diverse populations.
  • Short-term interactions do not capture long-term adaptation; longitudinal research is needed.
  • Findings are limited to game-based contexts; validation in high-stakes applications like rehabilitation is required.
  • Exploration of other actuation modalities and body areas is necessary.

Summary

This paper investigates how bodily-integrated systems initiating movements with their own logic shape user experiences of shared control. Through three exoskeleton-based game scenarios, it examines relational dynamics of proxy, competition, and collaboration. Findings reveal fluid agency and ownership, ethical concerns, and the experiential significance of symmetry in movements. The study contributes design implications for crafting bodily-integrated systems that balance autonomy, transparency, and user-centered control. These insights are applicable to fields such as rehabilitation, assistive technologies, and embodied play, offering a foundation for future exploration of human-machine co-performance.