The Library of Utopia People Power 2.0
Hand waving: A software plug-in called DepthJS makes it possible to control a Web browser using the Kinect.
MIT Media Lab
But the Holy Grail—controlling a computer without touching it—proves hard to achieve.
Soon after Microsoft released the Kinect gaming device, hackers found a way to pull raw data out of the system, radically expanding its potential uses. Enthusiasts have used the hardware to draw 3-D doodles in the air with hand movements, to play with virtual onscreen characters, and allow a robot to recognize gestures and map its surroundings.
But one of the biggest goals of Kinect hackers—controlling a computer with gestures—is proving difficult to achieve.
Researchers at MIT's Media Lab have created a new Chrome Web browser extension that lets users interact with any Web page via the Kinect if the device is plugged into a computer. Their project is one test case for the promise and limitations of hacking Microsoft's gaming peripheral for nongaming uses.
The extension, called DepthJS, uses JavaScript to translate a small number of hand gestures into commands that can be executed by the browser. For example, a rapid arm movement to the left switches between open browser windows. Opening and closing a hand quickly acts as a mouse click.
The goal isn't really to use the Kinect as a practical means of browsing the Web. Instead, DepthJS is meant to act as the interface between a variety of Web applications and the gestures captured by Kinect.
"Getting Kinect's events into the Web browser is all about lowering the cost of entry to exploring and creating applications using depth information," says Doug Fritz of the Fluid Interfaces group at MIT, who worked on the project. Computer users spend most of their time in the Web browser, Fritz notes. And most computer programmers (especially Web developers) know how to use JavaScript. This makes it an easy point of entry for Kinect programming.
One trouble is that unlike using a mouse, keyboard, or touch screen, there is no widely recognized (or naturally intuitive) vocabulary for gestural computing. Microsoft has developed a small number of gestures to let Kinect users navigate menus and browse media on the Xbox.
"Most of us hadn't even used a Kinect with the Xbox before we started working, so we weren't really burdened by the gesture language Microsoft has developed," says Fritz. The team was inspired by the iPhone's multitouch gestures and work by 3-D computing pioneer John Underkoffler. Surprisingly, some of the gestures created for DepthJS are similar to those Microsoft came up with. "Right now we are in that state of rapid change where people are remixing familiar interaction techniques with what feels natural," Fritz said.
Limor Fried and Phillip Torrone from Adafruit Industries, a company that supplies equipment to hardware hackers, helped kick off the race to hack the Kinect by putting out a bounty of $3,000 for software that could connect the device to a regular computer.
Both are excited about the future of the Kinect as an off-the-shelf sensor for everything from high-end robotics to art projects. Developers have created a steady stream of videos of different applications using the Kinect. "These videos are really just proof-of-concepts that show some of the possibilities for further development," says Fried.
Voltage is the difference of electrical potential between two points of an electrical or electronic circuit, expressed in volts. It measures the potential energy of an electric field to cause an electric current in an electrical conductor.
Most measurement devices can measure voltage. Two common voltage measurements are direct current (DC) and alternating current (AC).
Learn the fundamentals of creating an AC or DC voltage measurement system. See how to properly connect the signals to your data acquisition system for accurate acquisition.
This document is part of the How-To Guide for Most Common Measurements centralized resource portal.
View full PDF >