Embodying the Phantom

Abstract

This paper presents a two-point torso prediction system designed for use in virtual reality (VR) mirror therapy apps for individuals living with phantom limb pain (PLP) following an upper-limb amputation. PLP affects up to 80% of individuals with limb loss, significantly impacting their quality of life and contributing to depression and anxiety. While traditional mirror therapy can be effective in treating pain, modern VR apps offer greater flexibility and customization. However, many existing VR interventions rely on expensive external sensors and complex hardware setups, creating societal and economic barriers that limit widespread and at-home accessibility. To address this, we developed a system that estimates torso orientation using a two-point tracking system (the head and one hand), utilizing only consumer VR devices. Operating at the engine level without relying on external sensors or custom simultaneous localization and mapping (SLAM) datasets, this hardware-agnostic, six degrees of freedom solution facilitates accessible room-scale VR development. This paper outlines the technical design of the system and introduces the upcoming usability trial designed to test its viability as an accessible, inclusive, and low-cost intervention.