I  communicate with a computer system. I have always used IBM compatible computers,  on my wheel chair. They run from batteries under the wheel chair,
although an  internal battery will keep the computer running for an hour if necessary. The  screen is mounted on the arm of the wheel chair where I can see
it, more recent  systems have the whole computer in a box on this arm. The original systems were  put together for me by David Mason, of Cambridge
Adaptive  Communications. This company manufacture and supply a variety of products to  help people with communication problems express themselves. Recently, Intel engineers designed a new computer for me powered by a  Pentium II processor, which I now use.

On the computer, I run a program  called Equalizer™, written by a company called Words  Plus inc. A cursor  moves across the upper part of the screen. I can
stop it by pressing a switch in  my hand. This switch is my only interface with the computer. In this way I can  select words, which are printed on the lower part of the screen. When I have  built up a sentence, I can send it to a speech synthesizer. I use a separate  synthesizer, made by Speech+. It is the best I have heard, though it gives me an  accent that has been described variously as Scandinavian, American or Scottish.  I also can use Windows 98 through an interface called EZ Keys, again made by Words Plus. I  am able to control the mouse with the switch through cleverly selected process  from a small box shown on the desktop. I can also write text using similar  menu's to those in Equalizer.

I can save what I write to disk. I write  papers using a formatting program called TEX. I can write equations in words,  and the program translates them into symbols, and prints them out on paper in  the appropriate type. I can also give lectures. I write the lecture beforehand,  and save it on disk. I can then send it to the speech synthesiser, a sentence at  a time. It works quite well, and I can try out the lecture, and polish it,  before I give it. 

Stephen Hawking


Recent Improvements

Professor Hawking is determined that he is able to keep up with the  recent improvements in computer and communication technology. Below are some of  the recent improvements, which  have been carried out on the system within the  last 12 months.


In non-wireless  areas, Intel manage a 3G account for us so that Professor Hawking is  able to use the internet from anywhere in the world, via a PCMCIA 3G
card.  The computer has been replaced about once per year; it is currently (Jan  2009) running on a Lenovo Thinkpad T60 and the next model will have an X61 at its heart.

Upgrade to Windows XP (in around 2001)
The computer is running on Windows XP. For many years it has been  impossible to upgrade beyond Windows'98, because Professor Hawking's favourite  speech software, Equalizer by Words-Plus, was made in 1986, and was  designed to run only on DOS based operating systems. However, Intel has kindly  funded the conversion of the software to XP. This involved Words-Plus re-writing  the whole program for today’s operating system. 

Power
Due to  Professor Hawking's active lifestyle, it is impossible to power his chair  computer via the mains as he is never in one place long enough to make this  practical. Thus the laptop needs to be powered by the wheelchair batteries, which are similar to car batteries, in the back of  the chair.

Keep talking
It is essential  that Stephen is able to make use of a telephone. He is able to use Voice over IP, or connect his chair computer directly to a telephone  socket. The process works by sending digital commands from his computer  instructing the phone system to dial a number, answer the phone or hang up at  the end of a call.

Who's got  the remote?
Stephen has a  universally programmable infra-red remote control attached directly to his  computer system. This enables him to operate  many of the electronic items in his  home, such as televisions, video recorders and music centres. He also has a  radio control device which enables him to open doors and operate lights  throughout his home. He is now also able to operate doors within his workplace.  With the opening of the newly built Centre  for Mathematical  Sciences, he will be able to get about the building virtually unassisted.