MetamorHockey: A Projection-based Virtual Air Hockey Platform Featuring Transformable Mallet Shapes

ABSTRACT We propose a novel projection-based virtual air hockey system in which not only the puck but also the mallet is displayed as an image. Being a projected image, the mallet can freely “metamorphose” into different shapes, which expands the game design beyond the original air hockey. We discuss possible scenarios with a resizable mallet, with mallet shapes defined by drawing, and with a mallet whose collision conditions can be modified. A key challenge in implementation is to minimize the latency because the direct manipulation nature of the mallet positioning imposes a higher demand on latency than the puck positioning. By using a high-speed camera and a high-speed projector running at 420 fps, a satisfactorily quick tracking became possible such that we feel a projected mallet head to be an integral part of a mallet held by hand.