CapStones and ZebraWidgets

Abstract

Recent research proposes augmenting capacitive touch pads with tangible objects, enabling a new generation of mobile applications enhanced with tangible objects, such as game pieces and tangible controllers. In this paper, we extend the concept to capacitive tangibles consisting of multiple parts, such as stackable gaming pieces and tangible widgets with moving parts. We achieve this using a system of wires and connectors inside each block that causes the capacitance of the bottom-most block to reflect the entire assembly. We demonstrate three types of tangibles, called CapStones, Zebra Dials and Zebra Sliders that work with current consumer hardware and investigate what designs may become possible as touchscreen hardware evolves.Receiving raw capacitance values allows us to distinguish multiple levels of capacitance, which allows us to extract more than a single bit of information per contact. The simple design shown in Figure 11b exploits this. These analog CapStones use only two types of elements: (1) contacts that go straight through and (2) no contact, i.e., simply a blank space. The contacts form a marker that identifies the block.

Custom-made tangible interfaces with touchtokens

“…Multi-touch capacitive screens can also be used to transform tokens into interactive elements. The approach consists of building tokens that create a conductive circuit between users' fingers and the capacitive surface through the tokens' feet, that are in contact with the surface (e.g., [7,16,28]). As soon as the user touches the token, the feet become grounded and generate a drop in capacitance similar to a multi-touch pattern.…”

Passive yet Expressive TouchTokens

“…There are, however, a few exceptions that go beyond these limitations. Cap-Stones and ZebraWidgets [3] are capacitive units that can be assembled to configure different conductive circuits, enabling more manipulations with the tangibles that can, for example, be stacked or feature moving parts. PUCs [13] widgets rely on the principle of mutual capacitance so as to be detected even when users do not touch them.…”

Exploring Tangible Interactions with Radar Sensing

“…In a TUI, people interact with physical objects which are coupled to the control of computational artifacts and digital information. Such tangible interactions have been explored in education [6], musical expressiveness [24,43], input [12,14] and data manipulation [47,55]. This paper proposes the use of miniature radar sensing [69] to enhance such interactions.…”

“…Research on sensing and tracking objects to facilitate tangible interactions, is a well established field with techniques relying on the use of cameras [6,9,15], capacitive sensing [14,50], fiducial markers [24], sound [38], magnets [11,12,30] and tags (e.g., RFID) [28,29,31,53]. However, these techniques can often involve complex tracking technologies, bespoke infrastructures or object modification.…”