Abstract
Changes of the human interface is discussed according to the changes of means for work; from tools to machines, from machines to electrical machines (computers). When we use a tool, the operation is mainly hand/arm movements with high degree of freedom. The feedback of the operation from the tool is mainly somatosensory. The operation of a machine is done by simple operation, and feedback from the machine is obtained through visual channel. The operational movement to a computer which has a keyboard and a visual display terminal has less degree of freedom than that to a machine, and the feedback strongly depends upon the visual channel. However, graphic user interfaces (GUIs) let the operator to use two dimensional movements of the operation because the operator moves his hand to use a mouse type interface device. Recently, technologies for the virtual reality and those for the multi-modal interface allow to introduce the three dimensional hand movement to the computer operation and tactile/force display to obtain feedback from the computer. When the means of work changed from tool to machine, the operation became simple and visual feedback became important. However, the new technologies can make the human-interface of the computer to be closer to that of the tool. There are also technology trends to introduce verbal communication to the human-interface.
