It seems incredible to believe that of all the people on the planet, Stephen Hawking’s communication system has never used the sort of predictive typing found in modern smartphones, or even a backspace key. Now it does, via a partnership between Intel and Swiftkey.
Hawking, who suffers from an advanced stage of amyotrophic lateral sclerosis (also known as ALS or Lou Gehrig’s disease), communicates entirely through a text-based communication system controlled by his facial muscles. Up until now, the means of input has been a continually scrolling cursor that cycles through the letters of the alphabet, which Hawking “selected” by twitching a muscle in his cheek. That equated to about one or two words per minute, according to Intel chief technical officer Justin Rattner, in 2013.
Intel and Hawking have worked together for more than a decade, and Intel has said that it’s tried to improve the communications system that Hawking and other ALS patients used. On Tuesday, Intel released the ACAT (Assistive Context Aware Toolkit) designed to do just that.

Stephen Hawking in his library at home.
In 2013, Hawking’s communication system consisted of a tablet PC with a forward-facing Webcam that he can use to place Skype calls, according to Scientific American. A black box beneath his wheelchair contains an audio amplifier and voltage regulators. It also has a USB hardware key that receives the input from an infrared sensor on Hawking’s eyeglasses, which detects changes in light as he twitches his cheek. A hardware voice synthesizer sits in another black box on the back of the chair and receives commands from the computer via a USB-based serial port.
Software improvements, not hardware
ACAT doesn’t improve the hardware, but rather the software used to interpret Hawking’s facial movements into computer commands. ACAT has doubled Hawking’s typing speed. It’s also achieved a 10-times improvement in common tasks, such as moving a mouse and opening email—true challenges for someone who can’t push a mouse around. Intel prepared a video showing off the system in action.
WiredUK reports that initially, Intel thought about EEG sensors, gestures, or other complex ways of communicating that could actually convey more data in less amounts of time. That didn’t work, however: EEG sensors weren’t able to pick up the signals they needed from Hawking’s brain, and Hawking—a man who has never operated an iPhone—wasn’t quite sure initially how to use predictive text, as he preferred his slow, but precise, typing method. Gaze sensors failed, too, blocked by Hawking’s drooping eyelids.
Intel moved to a combination of predictive text input, as well as algorithms that suggest “hole” after “black,” for example. A backspace key can also delete text and back out of operations.
As ALS is a progressively degenerative disease, Hawking’s ability to communicate is decreasing. Predictive input will become more of a necessity as the disease advances. Before 2008, Hawking could type 15 words a minute, using a thumb clicker. Now, at 78, he is too weak to use it. What Intel and Hawking hope, however, is that the new system will help Hawking communicate for as long as he can.