Extended Fitts' Law for Three-Dimensional Environment

Abstract

This study explored an extended three-dimensional Fitts' law that is more suited for the pointing task than the conventional Fitts' law. The experiments were conducted under the manipulation of the distance to the target, size of the target, and direction of the target's location that can be described by two angles, θ1 and θ2. Considering the starting point as the center of coordinates, θ1 is the angle between the positive z-axis and the target location and θ2 is the angle between the positive y-axis and the projected target location on the x-y plane. From the experimental results, we confirmed that all four variables significantly affect the movement time. As we extended the index of difficulty of the conventional Fitts' model by incorporating θ1 and θ2, we established an extended Fitts' model that showed better accordance with the empirical data than the conventional Fitts' model and 3D Fitts' law of Murata and Iwase, in terms of the r 2 and the standard error of the residual between the measured movement time and the predicted value.

Extended Fitts' Law for Dual Task : Pointing on IVIS during Simulated Driving

“…터치스크린을 포함한 포인팅 작업에서 타겟 크기와 포인팅 시간 사이의 관계에 대한 대표적인 모델로는 Fitts' law (Fitts, 1954)가 있다. Fitts' law는 인간의 지각, 인지, 운동 과정을 기반 으로 하는 인간 정신과 운동 행동에 대한 모델로 정보처리이 론에 바탕을 두고 있는 법칙이다 (Mackenzie, 1989;Park and Myung, 2012 (Card et al, 1978;Hong and Kim, 2005;Johnsgard, 1994), 글러브 (Johnsgard, 1994), 조이스틱 (Card et al, 1978;Jagacinski and Monk, 1985), 터치스크린 (Epps, 1986, Parhi et al, 2006, 휴대전화 키패드 (Hong, 2004) 등의 다양한 기기 환경에서의 포 인팅 작업에서도 Fitts' law가 성립함을 보였으며, 2D 환경 뿐 아니라 3D 환경에서도 성립함을 보였다 (Cha and Myung, 2010;Grossman and Balakrishnan, 2004;Murata and Iwase, 2001). 뿐만 아니라 발 (Park and Myung, 2012), 혀 (Yousefi et al, 2010 (Chaparro et al, 2005;Horrey and Wickens, 2002;Levy et al, 2006;Wester et al, 2008).…”