USI research at the forefront of next generation 3D printing and digital drawing

The relentless digitalisation of advanced economies makes the future look very bright for R&D in modern digital technologies, especially in the fascinating and vast world of computer graphics and interactive techniques – where USI academics consistently exhibits cutting-edge research. This year’s two world-class conferences – ACM SIGGRAPH and ACM SIGGRAPH Asia – showcased the latest findings in, respectively, digital drawing technology and 3D printing published by Michal Piovarči, a PhD graduate from the USI Faculty of Informatics.

Since 1974, the Association for Computing Machinery (ACM) Special Interest Group on Computer Graphics and Interactive Techniques (SIGGRAPH) holds its annual conferences in the U.S. and, since 2008, in Asia. These are the most important conferences worldwide, inviting academics and industry representatives to discover and discuss the latest findings in the field.

Moving towards realistic 3D printing

At the Asian conference, in December, Dr. Michal Piovarči presented his work authored together with researchers and engineers from MIT, Princeton, Max Planck Institute, and USI – a new system that enables realistic variations in glossiness across 3D-printed surfaces. The advance is set to find applications such as fine art reproduction with near-flawless replicas that could be thus distributed to museums without access to originals, as well as the design and creation of more realistic-looking prosthetics. “The system is based on a novel printing hardware capable of processing highly viscous varnishes like those used in oil paintings”, explains Prof. Piotr Didyk, the PhD supervisor of Dr. Piovarči at the USI Faculty of Informatics, and co-authored the paper. “To reproduce desired reflectance these varnishes are deposited on the surface as tiny droplets. In our work we propose a numerical model that predicts the appearance of various varnish mixtures and estimates the perceived quality of the surface finish. We show that the hardware controlled by novel algorithms can reproduce the appearance of various materials ranging from wood to metal”. Read more about this work in the MIT News article here >> https://news.mit.edu/2020/3d-printer-gloss-1202

Digital drawing and haptic responsiveness

Digital drawing tools are now standard in art and design workflows, offering comfort, portability, and precision. At the same time, artists continue to work with long-standing, traditional drawing tools – paper, pencil, etc. One feature of traditional tools is the specific and diverse range of haptic (or tactile) responses provided by them, which in the digital domain is still a challenge to meet. At the SIGGRAPH conference, which took place in August, Dr. Piovarči presented his work in which he addresses the problem of fabricating digital drawing tools that closely match the haptic response of their traditional counterparts. This requires the formulation and solution of a complex, co-optimization of both digital styli and the drawing surfaces they move upon. As Dr. Piovarči explains, “the key observation in our work, which was performed in collaboration with Adobe Systems and the University of Toronto, is that in the presence of fabrication limitations attempting to directly reproduce the geometry and materials of traditional tools leads to suboptimal haptic response. Instead, much better results can be achieved when optimizing perceptually relevant properties of the object. They demonstrate that by combining human perception with computation, it is possible to manufacture digital styli that feel like pens, pencils, or charcoal”.

For further information on the activities of the Perception, Display, and Fabrication Group, headed by Prof. Piotr Didyk at the USI Faculty of Informatics: 
www.pdf.inf.usi.ch/