Madgets are actuated controls that can be moved by both the user and the software.
Madgets is the successor of the SLAP Widgets project. SLAP Widgets are flexible, general-purpose for interactive tabletops. However, since they are passive, the communication between user and table is unidirectional. If a control is placed on the surface, the software cannot change its physical state. This can easily lead to inconsistency, e.g., if two remote user share physical widgets. Madgets, magnetic widgets, solves this issue.
The project is based on an interactive tabletop with an embedded array of electromagnets. Our software can control the strength and polarization of every individual electromagnet. Madgets are designed like SLAP Widgets but contain additional permanent magnets. The array of electromagnets beneath the touch-sensitive surface employs the electromagnetic fields to attract or repel these permanent magnets. Thereby, these physical controls can be arbitrarily moved and configured via software. The position of objects on the surface is sensed via fiber-optical tracking. Fiber optical cables are placed next and inside electromagnets and allow a camera inside the table see past the opaque electromagnets.
Madgets increases the design space of physical tabletop objects:
- Applications can freely move, rotate, and configure physical objects on the surface
- GUI concepts such as load/save and undo/redo can be transferred to tangible objects
- Electrical and mechanical power can be transferred from the surface into physical objects, either via induction or via electromagnetic fields that actuate mechanical wheels.
- The software can actuate into the third dimension and move parts of tangibles vertically, e.g., the plate of a button
- Quickly switching the polarization of electromagnets lets Madgets vibrate which is a useful feedback channel
- Electromagnetism can be used to change physical effects, such as friction, spring resistance, perceived weight, or dynamic notches, in tangible objects on the fly (see video).
||This project is part of my PhD.
- Hardware infrastructure: Interactive tabletop with embedded array of electromagnets and fiber optical tracking mechanism. Custom-made circuit boards and mbed controller trigger actuation process. UI rendering via LCD panel with backlighting via electroluminescence foil.
- Tangibles: Custom-made by laser-cutting acrylic, attached paper-based markers for tracking, permanent magnets enable electromagnetic actuation
- Programming languages: Objective-C, C++ (Mac OS X), C++ (mbed microcontroller)
- Used frameworks: OpenGL, MultiTouchFramework, SLAP Framework, Coin-or linear programming library
- Malte Weiss
- Florian Schwarz
- Simon Jakubowski
- Jan Borchers
- Short paper
Malte Weiss, Christian Remy, Jan Borchers. Rendering Physical Effects in Tabletop Controls. In Proceedings of the 2011 annual conference on Human factors in computing systems. ACM, 2011. (27% acceptance rate)
- Full paper
Malte Weiss, Florian Schwarz, Simon Jakubowski, Jan Borchers. Madgets: Actuating Widgets on Interactive Tabletops. In Proceedings of the 23nd annual ACM symposium on User interface software and technology. ACM, 2010. (18% acceptance rate)
- Poster paper
Malte Weiss, Florian Schwarz, Jan Borchers. Actuated Translucent Controls for Dynamic Tangible Applications on Interactive Tabletops. In ITS '09: Extended Abstracts of ACM International Conference on Interactive Tabletops and Surfaces. ACM, November 2009.