re are several technical problems that must be solved before everyday haptic applications can become available. The key problem is the long time delay, due to Internet traffic, between when one user "touches" the on-screen box and when the second user feels the resulting force. "Each user must do the task very slowly or the synchronization is lost," Srinivasan says. In that cir- cumstance, the box vibrates both visually and to the touch, making the task much more difficult. Srinivasan is confident, however, that the time delay can be reduced. "Even in our normal touch, there's a time delay between when you touch something and when those signals arrive in your brain," he says. "So in a sense, the brain is teleoperating through the hand." A one-way trip from hand to brain takes about 30 milliseconds; that same trip from MIT to London takes 150-200 milliseconds, depending on network traffic. "If the Internet time delays are reduced to values less than the time delay between the brain and hand, I would PROJECTION KEYBOARDS expect that the Internet task would feel very natural," Srinivasan says. Although improving network speeds is the researchers' main hurdle, they also hope to improve the robotic arm and its capabilities, as well as the algorithms that allow the user to "feel" via computer. 9.5 PROJECTION KEYBOARDS Current-generation mobile phones and PDAs are limited by their data input technologies. Keyboards still take up too much physical space and handwrit- ing recognition is time consuming and clumsy. Canesta, a San Jose, Calif.-based input technology developer, aims to improve mobile device data input with its new "projection keyboard." The product creates a full-sized keyboard and mouse out of thin air via projected beams of light. "Electronic perception technology" is used to track finger movements in three dimensions as the user types on the image of a keyboard that's projected on any flat surface in front of the mobile device. No acces- sories are required. The technology is designed to make mobile device