Closed-Loop System with Biofeedback for Engagement Control in Virtual Rehabilitation

Abstract

This paper proposes the methodology to design a closed-loop system to control presence in a virtual rehabilitation setup, as a believed equivalence to therapeutic engagement and an improvement strategy of motor function recovery. This proposal starts with an analogy of adherence, defined by acceptance, participation and fulfillment (these last two indicators of engagement) with presence, measurable by means of subjective questionnaires and real-time biometrics (psychophysiology, biomechanics and task-performance). These objective measurements shape the feedback of a control system composed by a subject-state classifier and a controller based in soft computing to assure higher levels of presence via control rules that modify a virtual reality (VR) structure and code. This also describes the design of a previous open-loop setup that defines the signals that had better reflected emotions and presence states on task performance, after adjust VR variables that are classified by layers in a games design approach.