Bi-level and anti-aliased rendering methods for a low-resolution 2D vibrotactile array

We investigate rendering methods for 2D tactile arrays. We present four rendering methods, two of which are anti-aliased methods to improve display quality and smoothness. We describe three experiments to evaluate the methods. The first experiment compares them based on subjective ratings and finds that anti-aliased methods improve perceived quality and smoothness. The second experiment investigates the potential for one approach to communicate information at a sub-tactor resolution, based on the shortest line segment allowing identification of its direction. The third experiment is a shape discrimination experiment and finds that only one of the approaches allows reasonable discrimination for the selected shapes.