Hasso-Plattner-Institut für Softwaresystemtechnik

Human-Computer Interaction group

Hasso Plattner Institute

Prof.-Dr.-Helmert-Str. 2-3
D-14482 Potsdam, Germany

Prof. Patrick Baudisch





Tabletop computers cannot become larger than arm’s length without giving up direct touch. This prevents tabletop applications from dealing with more than a few dozen on-screen objects. We propose direct touch surfaces that are orders of magnitude larger by integrating high-resolution multi-touch into back-projected floors, while maintaining the purpose and interaction concepts of tabletop, i.e., direct manipulation.

We based our design on frustrated total internal reflection because its ability to sense pressure allows the device to see users’ soles when applied to a floor. We demonstrate how this allows us to recognize foot postures and to identify users. These two functions form the basis of our system. They allow the floor to ignore inactive users, identify and track users based on their shoes, enable high-precision interaction, invoke menus, as well as track heads and allow users to control several multiple degrees of freedom by balancing their feet.

Mutitoe is a research project by Caroline Fetzer, Thomas Augsten, Konstantin Kaefer, Dorian Kanitz, Rene Meusel, Thomas Stoff, Christian Holz, Torsten Becker, and Patrick Baudisch at the Human Computer Interaction Lab at Hasso Plattner Institute.

Youtube video (2min)




Fetzer, C., Kaefer, K., Augsten, T., Meusel, R., Kanitz, D., Stoff, T, Becker, T, Holz, C. and Baudisch, P. Multitoe: High-Precision Interaction with Back-Projected Floors Based on High-Resolution Multi-Touch Input. In Proceedings of UIST 2010, pp. 209-218.

PDF (3.2M) | PPT+Video (186.3M) | Video

Watch how the 1.2 ton multitoe glass floor was installed in our lab

Watch the Multitoe paper presentation at UIST on youtube (15min):


Computer Vision based on FTIR Sensing



Supported by

Related Projects

GravitySpace (fullpaper at CHI 2013) tracks users and their poses in smart rooms based on the latest 8m2 version of our pressure-sensing multitoe floor.


Multitoe project on German TV , January, 5, 2011

Multitoe at TEDx Youth Berlin (Video, 3:38++) November 14, 2010

Touch floors could be next step in computer interfaces. In New Scientist, April 13, 2010 (Video)

Multitoe floor shows us the logical next step. Engadget, April 13, 2010

Multitoe: Get ready to tap, zoom, three-toe swipe. In c'net. April 13, 2010.

Multitoe Project Offers New Touch Interface. In PC World, April 13, 2010. (interview video)

Multitoe Turns Floors Into Massive Multitouch Screens You Control With Your Feet. In Popular Science, April 13, 2010.


German Television about Multitoe



[Photo credit Kay Herschelmann]