Relationships bewteen usability and number of buttons of a Universal Remote Console -Preliminary experimental result-

Usability, or easiness of operation of a console such as URC, has been investigated in terms of the optimum number of buttons of the console. The action of console operation is consisted of two major processes, that is, cognition of the button and motion of hand to press it. Ease of cognition will be decreased in accordance with increase in the number of buttons. Conversely, increased number of buttons will be useful for quick switch operation. Therefore, it is expected that the optimum number of buttons which minimizes the total operation time of a console exists. To verify this hypothesis, several virtual consoles equipped with different number of buttons were developed on a PC. Subjects were asked to input designated family name as input data by using those consoles and ease of operation was evaluated by the operation time among several subjects. As easily imagined, ease of operation, or usability in terms of the operation time showed the maximum value when the number of buttons was approximately 18 in this study.