Over the past few months, Apple, Huawei, ZTE, and others have made splashes in the smartphone world with tech accurate enough to measure the amount of downward force on a screen, or “force touch,” as the capability’s become known.
Only a select few new phones sport it — short of a significant amount of soldering, older handsets can’t be retrofitted with the combo of sensors and motors required. But researchers at the University of Michigan may have discovered a low-cost, easy solution: a 3D Touch-like system of feedback that’s adaptable to practically any smartphone, recognizes when weight’s being applied to the touchscreen, and that can even tell when the phone’s being squeezed.
It sounds miraculous at first, but the engineers’ software prototype, ForcePhone, is grounded in clever audiology. Once booted, the app generates a constant, 18 kHz tone inaudible to human ears that the phone emits through its speakers. When force is applied to the phone’s touchscreen with a finger or object, the resulting acoustic shift — a nearly microscopic expansion and contraction of the tiny, cavernous spaces within the handset’s housing — alter the tonal frequency. The phone’s microphone picks up those changes, and ForcePhone translates them into commands that apps and games can interpret. It’s essentially sonar.
The squeeze of a hand could flip an eBook’s pages, for example, or pop open a previously hidden menu of options. And sequential squeezes could trigger preprogrammed applications, alarms, and other routines.
“You don’t need a special screen or built-in sensors to do this. Now, this functionality can be realized on any phone” said Kang Shin, a professor at the University of Michigan’s Department of Electrical Engineering and Computer Science and project lead on ForcePhone. “We’ve augmented the user interface without requiring any special built-in sensors.”
Shin, much like Apple, Huawei, and others, see force touch as a paradigm shift in interactivity.
“I think we’re offering a natural interface, like how you turn a knob,” said Yu Chih Tung, a doctoral student in the University of Michigan’s computer science program who partnered with Shin to create ForcePhone. “It’s the next step forward from a basic touch interface, and it can complement other gestured communication channels and voice.”
ForcePhone’s still in the experimental stages, but Shin and Tung plan to present an update at a conference in Singapore in late June. Here’s hoping that phone manufacturers take notice.
