Force-sensing touchpad to reach ultrabooks next year

Researchers at the User Interface Software Technology conference this week demonstrated unique projects that took advantage of a new, pressure-sensitive 'forcepad' that could debut in ultrabooks as soon as next year.

Synaptics gave the forcepad to more than two dozen academic research groups, which were challenged to come up with novel uses for the device. It's like a touchpad, but in addition to the usual swiping gestures it can sense how much pressure is being applied, adding another dimension for control.

One team, from RWTH Aachen University, created Forceposé, an application that lets Mac users "push" through a stack of overlapping windows, revealing the ones underneath. How far into the stack users go depends on how much pressure they apply to the forcepad.

"We added another dimension into browsing overlapping windows," said Christian Corsten, a researcher at RWTH Aachen University. "Normally when you have a stack of windows you need to move them away to grab a specific window, but [with what we did] you just push through the stack of windows with your finger."

To see the project in action, watch a video on YouTube.

Corsten said the project is different from the Exposé tool in Mac OS X (now called Mission Control) because in that mode, "everything gets smaller and moves to a different position and you notice that you're entering the Exposé mode."

Corsten said the team used the accessibility framework and Apple script to hack into the OS to get access to the different windows.

Another project took a novel approach to puppetry, with a marionette controlled not by a puppeteer but by a forcepad. The marionette hung on strings attached to a set of wheels and "servos," or little motors.

To see the puppet project, watch a video on YouTube.

As a researcher pressed his fingers on the forcepad, the puppet lifted its leg and waved its arms. Sliding his fingers across the pad made the puppet move left and right. One researcher said the project wouldn't have been possible with a traditional trackpad or with a touchscreen device like an iPad or iPhone.

"They don't give pressure information, so when you touch the screen it only knows where you're touching, but not how hard," said Paymahn Moghadasian, a student who worked on the project from the University of Manitoba.

The Synaptics forcepad can track five fingers at a 15-gram resolution, up to a kilogram, according to Anthony Searle, a systems design engineer. He said the forcepad will ship in ultrabooks next year, though Synaptics won't say yet which hardware partners it is working with.

The company showed the touchpad integrated into a prototype Lenovo ultrabook, but for most of the demonstrations at UIST, the touchpad connected to the laptops via USB.

The demonstration projects themselves, such as the puppet, are at the research stage and there are no immediate plans to commercialize them.