Usability Research Of Finger Moving Direction In Human Computer Interface

Touch technique is a friendly and natural human computer interface, and makes manipulating on the surface of touch sensing devices directly relying merely on bare fingers a reality.However, the occlusion of screen raised by fingers, low resolution of fingers and arm fatigue critically decrease the usability of touch sensing techniques. In order to overcome these drawbacks and improve user experience, researchers are studying the use of finger properties. Finger moving direction would be very useful to avoid the shortcomings of the occlusion raised by fingers and low resolution of fingers.This paper which researches on the usability of finger moving direction, starts with the analysis of detecting finger moving direction. Start to terminal point and track are two ways to record moving direction. Above all, in order to reflect user intent better, we make a comparison of the results obtained by these two methods in different conditions. As a result of all this, we have come to five conclusions. Firstly, the angle between the finger moving path and coordinate axes follow a normal distribution. Secondly, this study demonstrates that there is no significant difference in recording moving direction between two groups under the same conditions. Thirdly, the angles calculated by the two methods are not so different in the four quadrants. Fourthly, Start to terminal point and track can both reflect user intent. Therefore, the paper adopts start to terminal point method to record and calculate finger moving direction. Fifthly, a computer can theoretically identify the thirty two directions in a single plane if the system prompts users with directions. But, if there is no prompt, a computer can theoretically identify the sixteen directions in a single plane. On the base of analyses, we discuss the maximum number of detected finger moving direction in practice. And then we exploit the probable reasons which have influence on detecting the finger moving direction. Finally, finger moving direction is applied in Tetris game on touch sensing device. The game validates some theories of the paper.