Paper Reading #15: Madgets: Actuating Widgets on Interactive Tabletops

Reference Information
Madgets: Actuating Widgets on Interactive Tabletops
Malte Weiss, Florian Schwarz, Simon Jakubowski, Jan Borchers
Presented at UIST'10, October 3-6, 2010, New York, New York, USA

Author Bios

• Malte Weiss is a PhD student in the Media Computing Group at RWTH Aachen University. His work focuses on interactive surfaces and tangible user interfaces.

• Florian Schwarz is a Diploma Thesis student in the Media Computing Group at RWTH Aachen University. His work is in interactive tabletop computing.

• Simon Jakubowski is a student assistant in the Media Computing Group at RWTH Aachen University. He is working on two other projects besides this one.

• Jan Borchers is the head of the Media Computing Group at RWTH Aachen University. He holds a PhD from Darmstadt University of Technology in Computer Science and now explores HCI.

Summary
Hypothesis
The interactive tabletop that uses "Madgets" is an improvement over currently existing similar technologies because it can enable interaction with and actuation of complex physical controls and is easy to control, low-cost, and does not require any built-in electronics or power sources for actuation or tracking.

Methods
The authors created a prototype of the Madgets system and various sample controls for it, including radio buttons and slider knobs. They considered general purpose widgets, height, force feedback, water wheel Madgets (which transfer energy), and mechanical audio feedback as possibilities.

Results
Based on the usage of their prototype platform producing a new widget took less than an hour to produce. The tracking was done by using gluing the corresponding markers to the its control and this process took about two hours to do. Its performance shows the great possibility for allow cheaper and easier implementation as well as design.

Contents
The researchers first had to build the devices to be used seeing as most of what is needed is not currently available on the market. The IR projector was built by upgrading a DLP projector and the table had to be made with the diffuser layer above the touch-glass because the touch-glass would reflect on observers and degrade the light. Detecting multi-touch was implemented using a combination of touch recognition and the Diffused-Illumination(DI) method in a clever way by simulating backgrounds, inspecting suspected objects in a region of interest (ROI) by projecting white regions onto it, and smoothing out feedback with a Kalman filter. Due to the camera and projectors being independent systems, it was necessary to use software synchronization to keep the cameras from feeding old data to the projectors.

Discussion
I believe that the researchers put together an effective system, but it seems like they fell short of making it truly rapid prototyping kit. It takes several hours to get widgets fully integrated into the system which is way too long and the user study also had much lacking.