VTK4AR: An Object Oriented Framework for Scientific Visualization of CAE Data in Augmented Reality

In the last ten years many Augmented Reality (AR) applications for Scientific Visualization have been developed, attesting the effectiveness of this technique for data visualization and interaction. In all these applications, a software framework for scientific visualization was used to process data to be visualized, while an AR system was employed to display these data within an AR context. Hence, everyone who intended to approach the development of such applications should become necessarily familiar with the scientific visualization framework and the augmented reality one. This is of course an hurdle for the applications development, and the idea behind this work is exactly to provide a software framework that simplifies the development of such applications. With this in mind, we extended an existing and powerful open source library for scientific visualization (VTK) with few but useful classes for the interfacing with an existing AR library (ARToolKit) to easily handle the video see-through and the video-tracking functionalities. The resulting software tool, called VTK4AR, can be considered as an all in one software framework specific for scientific visualization in AR. Moreover, since it is built on top of VTK, it will be possible to employ a wide range of visualization techniques in many application fields. In particular, it has been tested in two AR applications: one for displaying data relative to a CFD simulation of a flow past a helmet, and another for displaying the forming error obtained prototyping an ankle support with the incremental forming technique.