A Projector-based Movable Hand-held Display System for Interactive 3D Model Exhibition

Traditional display systems usually display objects on static screens (monitors, walls etc) and the interaction between the displaying object and the viewer can only be via keyboard and mouse. It will be attractive if we display the object to a hand-held screen and interact with it using our hands as we do in our daily lives. In this paper, we propose a prototype system by projecting the object to a hand-held foam sphere. The target is to develop an interactive 3D model exhibition tool without the viewer having to wear spectacles. In our system, the viewer holds the sphere with his hands and moves it freely. Meanwhile we project well-tailored images onto the sphere coincident with the movement of it, giving the viewer a virtual perception as if the object is sitting inside the sphere and being moved by the viewer. The design goals of our system are low-cost, real-time, live, and 3D. An off-the-shelf projector-camera pair is first calibrated via a simple but efficient algorithm. Vision based algorithms are proposed to detect the sphere and track its subsequent motion. To adapt to different application scenarios, we develop two kinds of configurations to track the sphere. The projection image is generated based on the projective geometry among the projector, sphere, camera and the viewer. We discuss how to allocate the view spot and warp the projection image. We also present the result and the performance evaluation of the system.