CoplayingVR: Understanding User Experience in Shared Control in Virtual Reality

Overview

CoplayingVR is a networked VR system that lets two players share control of a single virtual avatar by each controlling one of its hands. Built on Unity with Photon networking and deployed on Meta Quest headsets, CoplayingVR investigates how shared hand control — an unconstrained, realistic form of shared embodiment — affects user experience, task performance, and the sense of agency and body ownership in typical VR gaming scenarios.

Vision

Shared control in VR is an emerging interaction paradigm where multiple users inhabit a common virtual avatar or form. While previous research explored shared control in highly constrained settings, real gaming and collaboration demand unrestricted hand movements and natural interaction. CoplayingVR brings insights from a scenario closer to real-world application: two players freely controlling the virtual character's left and right hands in actual VR games, revealing how physical embodiment and psychological factors intertwine to shape collaborative experiences.

How It Works

Input Control

Each player wears a VR headset and selects one of the avatar's hands (left or right) to control. Hand movements map directly from the player's controller to the corresponding virtual hand without blending or averaging — each player has full authority over their chosen hand.

Rendering & Synchronisation

Both players share a first-person perspective tethered to the avatar's head and body position. Players control their own head rotation independently to mitigate motion sickness. All gameplay actions are distributed to both headsets in real-time through a locally hosted Photon Server, achieving latency below 5ms.

Game Tasks

Three VR games were designed spanning different genres:

• Control Task (Peg-in-Hole): A precision manipulation task requiring both players to coordinate hand position and rotation.
• Balancing Task (Maze Board): A cooperative puzzle where two hands tilt a maze board to guide a ball, demanding synchronised movements.
• Shooting Task (Archery): A fast-paced action game where one hand aims the bow and the other draws and releases arrows.

Key Findings

A user study with 48 participants (paired into 24 dyads) comparing shared control and single-player modes revealed:

• Enhanced Game Experience: Shared control significantly improved Challenge, Competence, Flow, Positive Affect, Sensory and Imaginative Immersion, and reduced Negative Affect and Tension.
• Novice Performance Boost: Shared control significantly enhanced task efficiency for novice VR users without degrading experienced players' performance.
• Increased Agency & Ownership: A comparatively significant increase in sense of agency and body ownership emerged as the study progressed under shared control, suggesting adaptation and growing embodiment.
• Social Dynamics: Players reported the experience as novel, challenging, and socially engaging — describing it as requiring trust, communication, and mutual adaptation.

Applications

• Collaborative Gaming: Designing new game mechanics where players share a single character for unique cooperative challenges.
• Motor Skill Training: Leveraging shared control for skill transfer, where an expert guides a novice through shared hand movements.
• Rehabilitation: Using shared body experiences to motivate patients through engaging, collaborative VR exercises.
• Social VR: Creating intimate shared-body experiences that foster empathy, communication, and mutual understanding.