The E ects of Low Frame Rate on a Measure for User Performance in Virtual Environments

This report investigates the e ect of low frame rate on human performance in a desktop virtual environment. This is done using an objective measure of users' ability to perform a simple heading task at various frame rates (2.3{14.2 Hz). Two principal experiments are presented. The rst experiment shows that for a drop in frame rate from 11.5 Hz to 2.3 Hz, users' accuracy and time to complete the task degraded signi cantly. The second experiment reveals a continuous, asymptotic relationship between frame rate and performance for the chosen task. At low frame rates (up to 10-15 Hz) there is a sharp improvement in performance as frame rate increases. After around 15 Hz this increase is substantially less rapid. The results provide evidence for reinforcing that a minimum frame rate of around 15 Hz is necessary for virtual environments, but also that further increases in frame rate will continue to yield greater performance levels, albeit at a much reduced rate.