A simple and inexpensive telephone dialling aid for the disabled

The object of the work presented in the article is to design a simple and i nexpensive telephone dialling aid, which allows disabled people to operate telephones by themselves. The dialling aid consists of four main blocks: a joystick-based interface unit, a microprocessor control unit, a keypad trig gering circuit unit, and an LED output display unit. Ten people were asked to evaluate a prototype of the dialling aid. The evaluation criteria were b ased on the success rates and the time needed to dial a telephone number.