Natural exploration of 3D models

Abstract: We report on two interactive systems for natural exploration of 3D models. Manipulation and navigation of 3D virtual objects can be a difficult task for a novel user, specially with a common 2D display. With traditional input devices such as 3D mice, trackballs, etc. the interaction doesn’t insist directly on the models, but is mediated and not intuitive. Our user interface allows casual users to inspect 3D objects at various scales, panning, rotating, and zooming, all through hand manipulations analogous to the way people interact with the real world. We show the design and compare the tests on two alternative natural interfaces: multitouch and free-hand gestures. Both provide a natural dual-handed interaction and at the same time free the user from the need of adopting a separate device.

Authors: S. A. Iacolina, A. Soro, R. Scateni.
Natural exploration of 3D models.
ACM SIGCHI Italian Chapter (CHItaly 2011), 118-121.
Alghero, Italia, Settembre 2011.

Improving FTIR Based Multi-touch Sensors with IR Shadow Tracking.

Abstract: Frustrated Total Internal Reflection (FTIR) is a key technology for the design of multi-touch systems. With respect to other solutions, such as Diffused Illumination (DI) and Diffused Surface Illumination (DSI), FTIR based sensors suffer less from ambient IR noise, and is, thus, more robust to variable lighting conditions. However, FTIR does not provide (or is weak on) some desirable features, such as finger proximity and tracking quick gestures. This paper presents an improvement for FTIR based multi-touch sensing that partly addresses the above issues exploiting the shadows projected on the surface by the hands to improve the quality of the tracking system. The proposed solution exploits natural uncontrolled light to improve the tracking algorithm: it takes advantage of the natural IR noise to aid tracking, thus turning one of the main issues of MT sensors into a useful quality, making it possible to implement pre-contact feedback and enhance tracking precision.

Abstract: S. A. Iacolina, A. Soro, R. Scateni.
Improving FTIR Based Multi-touch Sensors with IR Shadow Tracking.
ACM SIGCHI EICS 2011, 241-245.
Pisa, Italia, Giugno 2011.

Natural Interaction and Computer Graphics Applications

Abstract: Natural Interaction with computers has been a challenging topic of research since the very beginning of the digital era and refers to the possibility, on the user’s part, of exploiting natural abilities to control the machine and interpret its outputs. If in the infancy of computer graphics this meant using visual representation and pen pointing, nowadays more refined techniques are needed to fit the wide range of applications, from home entertainment to virtual and augmented reality. This paper describes some advances in gesture, tangible and surface computing, showing how such interaction models, if treated as a continuum, improve the usability, accessibility and overall experience of computer graphics applications.

Authors: S. A. Iacolina, A. Lai, A. Soro, R. Scateni.
Natural Interaction and Computer Graphics Applications.
EuroGraphics Italian Chapter 2010, 141-146.
Genova, Italia, Novembre 2010.

Interactive Calibration of a Multi-Projector System in a Video-Wall Multi-Touch Environment.

Abstract: Wall-sized interactive displays gain more and more attention as a valuable tool for multiuser applications, but typically require the adoption of projectors tiles. Projectors tend to display deformed images, due to lens distortion and/or imperfection, and because they are almost never perfectly aligned to the projection surface. Multi-projector videowalls are typically bounded to the video architecture and to the specific application to be displayed. This makes it harder to develop interactive applications, in which a fine grained control of the coordinate transformations (to and from user space and model space) is required. This paper presents a solution to such issues: implementing the blending functionalities at an application level allows seamless development of multi-display interactive applications with multi-touch capabilities. The description of the multi-touch interaction, guaranteed by an array of cameras on the baseline of the wall, is beyond the scope of this work which focuses on calibration.

Authors: A. Lai, A. Soro, R. Scateni.
Interactive Calibration of a Multi-Projector System in a Video-Wall Multi-Touch Environment.
UIST 2010 Adjunct Proceedings, 437-438.
New York, NY, USA, Ottobre 2010.