Immersive virtual reality simulations for investigating physical activity and human interactions with technology in younger, older, and patient populations

This thesis investigates how immersive virtual reality (VR) simulations can utilize exertions, movements, and physical activities for human performance evaluation or physical training.;Two initial studies were conducted in this thesis with the purpose to understand human performance in VR. Generally speaking, there were human performance differences and similarities in VR and the physical environment. Human inaccuracy (i.e. error) when locating virtual targets was 1.64 times greater (p<.001) than locating physical targets, and participants spent 1.49 times more time (p=.01) to locate virtual targets than physical targets. When participants were asked to exert forces against virtual objects using virtual exertions (i.e. mapping of human-generated forceful actions, postures, and movements that are generally used to manipulate physical objects, against projections of objects in the hands as an interface into the virtual environment), muscle activity was generally greater than when exerting forces against physical objects of the same weight. Some similarities between VR and physical environment were also observed. Biceps muscle activity was positively related to the weight of both virtual and physical objects (p<.001), which suggested that human muscle activities may respond to the weight of virtual objects similar to how they would with the weight of physical objects.;Two additional studies demonstrated the use of VR for practical applications. One study examined driver functional range of motion during a blind spot checking task. Using virtual targets in VR as visual stimuli, drivers indicated when they were detected in the driver blind spot. The results indicated that functional range of motion was 15.6 degrees greater (p<.001) than conventional neck range of motion. The other study investigated how patients perform neck exercises directed by visual stimuli in VR. It was observed that patients performed neck rotation exercises approximately 2 degrees greater than what they initially indicated their neck rotation capacity to be (p=.005).;In conclusion, virtual reality was demonstrated as a flexible environment where visual stimuli can be programmed for various evoking physical actions and sensations. Research including, but not limited to human-VR interactions, human performance and behavior, and physical training and exercise can be conducted in VR.