Will gesture control become the future of
computer interfacing?
For many years, we interfaced with our computers using a keyboard and a mouse. But the arrival of touch screen technology has changed all that. Today, many of us will use touch as the main way to interact with our devices.
But
even touch technology has its limitations; the user has to make physical
contact with the device in question. Looking to address this issue, a number of
companies and researchers are developing new ways to make devices understand
what we want them to do – and gestures are being seen as a natural way of
interaction. And some tvs are already offering just this ability. Samsung's
Smart TVs, for example, support simple gesture control.
Fanie Duvenhage is director of Microchip's human machine
interface division. He said: "We're interested in how people connect with
technology and that interaction between people and machines is getting
interesting."
Gest IC technology, which is integrated
into the host device, uses thin sensing electrodes made from any conductive
material. Amongst the options are pcb traces and indium tin oxide coatings. The
company says this allows for visually appealing industrial designs with very
low additional system costs. The technology is also said to provide 100%
surface coverage, eliminating 'angle of view' blind spots found in other
technologies.Microchip has also supplied capacitive touch technology for some
years. Duvenhage said that, while capacitive touch is still widely used, it has
limitations. "The state of the art for capacitive touch only has a range
of a couple of inches “he pointed out.
GestIC technology
uses frequencies of around 100 kHz, with a wavelength of 3km. Because the
electrodes are much smaller, their magnetic component is practically zero and
no wave propagation takes place. Five electrodes are required by the system:
right, left, up, down and centre. When a hand, for example, enters the
electrical field, its distribution is distorted and the field lines intercepted
by the hand are shunted to ground through the human body. The proximity of the
body shifts the receiver electrode signal levels to a lower potential and this
can be detected. Digital signal processing determines the exact location of the
gesture and its direction. Duvenhage said: "GestIC has a detection range
of 15cm and, because it has low power consumption, can be always on”.
The first chip to enable the technology is the MGC3130.
Consuming as little as 150µW in its active sensing state, the MGC3130 is suited
for use in battery powered products even with it’s always on nature.
Gest IC technology uses the Colibri suite, an on chip library
of intuitive and natural human gestures. The Colibri suite combines a
stochastic Hidden Markov model and x/y/z hand position vectors to provide
designers with a reliable set of recognized 3d hand and finger gestures.
Examples include position tracking, flicks, circles and symbol gestures. These
can be used to perform functions such as on/off, open application, point,
click, and zoom and so on.
The MGC3130
supports a resolution of 150point/in and samples at 200Hz sampling rate to
detect the fastest motions. It
features automated self-calibration for high accuracy and has
integrated flash to support product upgrades. Interference from other RF sources
are avoided by a frequency hopping approach which shifts the detection
frequency within the range from 70 to 130 kHz.
Microchip claims it is working with input device and other
product manufacturers to implement efficient user input controls. Example
applications include taking advantage of the interface capabilities in Windows
8, using hovering motions and free space gesture controls, instead of
touchscreen interaction. Duvenhage believes Gest IC technology will be suited to a range
of markets. "Alongside consumer input devices," he said, "we
also see potential in automotive and medical applications." Microchip is
supporting developers with the Sabrewing single zone evaluation kit. Working
with the MGC3130, the kit provides a choice of 5 or 7in electrode sizes and
comes with the Aurea graphical user interface. This allow designers to match
their system commands to Microchip's ColibriSuite.
Sounds good
Sounds good
According to Microsoft Research, gestures are becoming an
increasingly popular way to interact with computers. However, it says deploying
robust gesture recognition sensors in existing mobile platforms can be
expensive. In a paper which describes its work, the team note that vision
based gesture recognition systems can be affected by variables such as lighting
conditions, while requiring reasonable amounts of processing power. The team
also points to Microsoft's Kinecttechnology, but suggests miniaturising this is
not likely in the near future. Looking to solve this problem, a team of researchers has
developed a system called SoundWave, which takes advantage of the speakers and
microphone found in most commodity devices.
Sidhant Gupta, a ubiquitous computing researcher, is part of the team, whose approach is based on the Doppler effect. "Sound Wave is a real time technique," said Gupta, "which uses speakers and a microphone to detect a range of gestures without the use of any special sensors." Sound Wave generates frequencies in the range between 18 and 22 kHz, which are frequency shifted when they reflect off moving objects, including the hand. "We use a microphone on the same device to pick up the frequency shifted signal and recognize the gesture," he continued. The system is also capable of detecting differences between gestures. For example, when the hand moves faster, the frequency shift is greater. And SoundWave can also understand when the user walks away from their laptop, for example, and can be set up to lock the device. Because Sound Wave uses frequencies above the range of human hearing, it can work alongside audible music. "The user can have music playing on their laptop while using Sound Wave,"Gupta Noted.
Sidhant Gupta, a ubiquitous computing researcher, is part of the team, whose approach is based on the Doppler effect. "Sound Wave is a real time technique," said Gupta, "which uses speakers and a microphone to detect a range of gestures without the use of any special sensors." Sound Wave generates frequencies in the range between 18 and 22 kHz, which are frequency shifted when they reflect off moving objects, including the hand. "We use a microphone on the same device to pick up the frequency shifted signal and recognize the gesture," he continued. The system is also capable of detecting differences between gestures. For example, when the hand moves faster, the frequency shift is greater. And SoundWave can also understand when the user walks away from their laptop, for example, and can be set up to lock the device. Because Sound Wave uses frequencies above the range of human hearing, it can work alongside audible music. "The user can have music playing on their laptop while using Sound Wave,"Gupta Noted.
In flight application
Researchers
from Thales are working on a gesture control system for in-flight entertainment
systems. According to the company, passengers will be able to interact
with a large screen, with the camera recognizing their motions and the system
responding much as if they were using a touch screen. The idea is based on
technology used in the Xbox games console, but Thales says the design goes
beyond games and to address many aspects of in flight entertainment content: movies,
music, gesture games and e-readers. But don't expect to
find gesture control towards the rear of the plane. This system is intended for
use by those who 'turn left' when they board..
