A pressure sensitive computer keyboard is presented that independently senses the force level on every depressed key. The design leverages existing membrane technologies and is suitable for low-cost, high-volume manufacturing. A number of representative applications are discussed.

In this paper we present novel input devices that combine the standard capabilities of a computer mouse with multi-touch sensing. Our goal is to enrich traditional pointer-based desktop interactions with touch and gestures. To chart the design space, we present five different multi-touch mouse implementations. Each explores a different touch sensing strategy, which leads to differing form-factors and hence interactive possibilities. In addition to the detailed description of hardware and software implementations of our prototypes, we discuss the relative strengths, limitations and affordances of these novel input devices as informed by the results of a preliminary user study.

We introduce a new type of interactive surface technology based on a switchable projection screen which can be made diffuse or clear under electronic control. The screen can be continuously switched between these two states so quickly that the change is imperceptible to the human eye. It is then possible to rear-project what is perceived as a stable image onto the display surface, when the screen is in fact transparent for half the time. The clear periods may be used to project a second, different image through the display onto objects held above the surface. At the same time, a camera mounted behind the screen can see out into the environment. We explore some of the possibilities this type of screen technology affords, allowing surface computing interactions to extend 'beyond the display'. We present a single self-contained system that combines these off-screen interactions with more typical multi-touch and tangible surface interactions. We describe the technical challenges in realizing our system, with the aim of allowing others to experiment with these new forms of interactive surfaces.

In this paper, we present a high speed optical motion capture method that can measure three dimensional motion, orientation, and incident illumination at tagged points in a scene. We use tracking tags that work in natural lighting conditions and can be imperceptibly embedded in attire or other objects. Our system supports an unlimited number of tags in a scene, with each tag uniquely identified to eliminate marker reacquisition issues. Our tags also provide incident illumination data which can be used to match scene lighting when inserting synthetic elements. The technique is therefore ideal for on-set motion capture or real-time broadcasting of virtual sets. Unlike previous methods that employ high speed cameras or scanning lasers, we capture the scene appearance using the simplest possible optical devices - a light-emitting diode (LED) with a passive binary mask used as the transmitter and a photosensor used as the receiver. We strategically place a set of optical transmitters to spatio-temporally encode the volume of interest. Photosensors attached to scene points demultiplex the coded optical signals from multiple transmitters, allowing us to compute not only receiver location and orientation but also their incident illumination and the reflectance of the surfaces to which the photosensors are attached. We use our untethered tag system, called Prakash, to demonstrate methods of adding special effects to captured videos that cannot be accomplished using pure vision techniques that rely on camera images.

The VeriChip is a Radio-Frequency Identification (RFID) tag produced commercially for implantation in human beings. Its proposed uses include identification of medical patients, physical access control, contactless retail payment, and even the tracing of kidnapping victims. As the authors explain, the VeriChip is vulnerable to simple, over-the-air spoofing attacks. In particular, an attacker capable of scanning a VeriChip, eavesdropping on its signal, or simply learning its serial number can create a spoof device whose radio appearance is indistinguishable from the original. We explore the practical implications of this security vulnerability. The authors argue that:1 The VeriChip should serve exclusively for identification, and not authentication or access control. 2 Paradoxically, for bearer safety, a VeriChip should be easy to spoof; an attacker then has less incentive to coerce victims or extract VeriChips from victims' bodies.