Students Develop New 3D Computer Mouse

Five students at the Worcester Polytechnic Institute have cooked up a new way to interact with computers, which they’ve dubbed the MagicMouse. The mouse brings new meaning to “point and click” by allowing users to actually point at objects on a screen using their index finger and manipulate them, even in 3D, using only the motion of the finger.

It works using a tiny ultrasonic transmitter that a user wears around his or her finger like a ring. The transmitter sends a signal every 16 milliseconds to an array of five receivers. Software then calculates the ring’s position in 3D space using time difference of arrival – the same way GPS systems work. The receivers are sensitive enough to detect even tiny delays in the signal from the ring, which the software can use to determine how far away the ring is. Using this data from all five receivers, the computer can accurately determine the ring’s movements. This all occurs in what appears to be real time to us.

The WPI students built the MagicMouse as part of a major qualifying project for their computer and electrical engineering degrees, and worked on it over the course of 21 weeks. Although they were required to build only a single prototype, they wanted the ring to be practical, so they kept the materials cheap. The whole system used only $155 worth of parts.

Applications for the ring right now might include navigating through CAD programs or 3D maps, but the students envision more creative uses for it if it ever becomes popular. For instance, they suggested the MagicMouse as a way for students to learn to conduct an orchestra, using different motions to control pitch, tempo and volume. “With a new interface like this, third party developers could design new applications that would take advantage of the intuitive connection between user input and motion on the screen,” their report suggested. “This device could pave the way for a new revolution in computerinput technology.”

The ring isn’t commercially available yet, but it will be featured in the June issue of Popular Science and the students plan to continue work on it.