This project, acquiring a high-fidelity instrument designed to facilitate and assess perception, interaction, and learning in immersive environments, pursues an ambitious research agenda dealing with people, their interactions with virtual environments, and the design factors underlying successful environments. The work aims to build a program to develop a better understanding of the cognitive capabilities of humans in immersive virtual environments, to inform the design process of such environments and to understand how humans reason about space. The instrument will be shared among diverse and interdisciplinary groups collaborating in the area of virtual environments, including Computer Science and Engineering (graphics, animation, artificial intelligence, human factors, robotic, etc.) and the Psychological Science (cognitive psychology, child development, rehabilitation engineering, brain sciences, etc.). The component parts of the instrument (comprising optical motion capture equipment, a head-mounted display with binocular eye-tracking, and high-performance wireless data gloves) allow the measurement, tracking, rendering, and animation of subjects in virtual environments (from their overall position, to their posture, to the actions of their hands and fingers) coupled with the measurement of their gaze. The project ranges from low-level research in how people experience virtual environments to user evaluations involving high-level interface and simulation design. Children with autism will also be studied. Broader Impacts: This project improves the quality of learning in virtual environments, reducing the time and cost of authoring and overcoming likely impediments to their widespread use. The instrument enables courses in robotics currently infeasible with real robots and provides experience for students. The work builds a scientific program to develop a better understanding of the cognitive capabilities of humans in immersive virtual environments and may be applied to understanding the development of children?s abilities to reason about space and to coordinate perceptual-motor skills as they develop. Moreover, it may help to treat autism spectrum disorder.